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Anil Seth on The Neuroscience of Consciousness, Sapir Whorf, and Daniel Dennett's ideas
November 23, 2020
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There's a lot of questions. This looks like some sort of super hard interview for some things. I hope you don't expect me to have answers for all of them. I'm here with Professor Anil Seth of neuroscience at the University of Sussex. There aren't many people who are brave enough to tackle consciousness scientifically. Maybe there's 1,000 people and there's
Maybe 5% of that are paragons in the field. So that's like 50 people, I'd say. And I would include Anil Seth in that. I'm super excited to speak with him. If you look up his talk on Ted, I believe it's one of the most viewed, we hallucinate realities. You might want to view that before watching this to get a, an overview of Seth point of views. I'm also here with Faraz who has a background in neuroscience and medical science and masters in it, actually medical science. And I thought it'd be great to have Faraz tag along.
This is going to be somewhat free flowing because me and Faraz aren't communicating with each other off screen in some way. So at points he might interject that it might overlap with mine, but that's fine. We'll just take it as it goes. Welcome. Thank you, Professor. Thank you, Kurt. And Faraz, it's a pleasure to be here. So Professor, what are you currently working on and how did you get interested in the field of consciousness? So, well, two different things. I mean,
Consciousness for me has always been interesting. It's one of those questions I think that pretty much everyone is interested in at some point in their lives, certainly when you're a kid, it's just one of these things, these big mysteries. How does it fit into our picture of the universe? How does it depend on the brain? What does it mean to be me? What happens when I die? And all these sort of big questions are things that most of us wonder about and then usually grow out of and
do something more normal with with life. So I've just been lucky enough to never have been forced to go out of these these questions. But of course that doesn't mean that every day is like 12 hours a day just trying to answer this big spooky mystery about consciousness. In fact day to day working in this area, working in this part of science translates into a whole variety of different things that are
related more or less directly to this big question. So just for example today we've been talking with my people from my research group and colleagues about various things like how do we mathematically get a grip on an emergent property? People often talk about consciousness as being emergent from the brain somehow but what does that mean mathematically? That's one thing. Another thing we were looking at
developing computer simulations of different kinds of hallucinations to get a better grip on how different kinds of visual hallucinations differ and what the underlying mechanisms in the brain might be. And then just before this meeting, I was with a PhD student at the very early stages trying to develop new kinds of experiments to understand the difference between what we might call gist perception, know that if you just
see a scene very quickly you can usually tell that it's a landscape or it's some very very basic features of perception come out very quickly but others require a bit longer to figure out oh am i looking at this person or that person or is it a car or what's what are the details going on so i'm very interested in thinking about how to explain these differences in visual perception so just to say there's just an awful lot of different
different specific questions that we can ask when we're trying to understand more about consciousness. Is it cool if we get some definitions out of the way? Yeah, I think that's always a good place to start. Right. Phenomenology, the way that you use it, I assume it's different than the philosophical doctrine of phenomenology, which is Husserl's, Heidegger's, and then there's particle phenomenology.
and I'm unclear when you say phenomenology. Exactly. What do you mean? Well, I mean, I must admit I play a little fast and loose with with the definitions. And it's but the way I mean it is probably quite close to the philosophical phenomenology of Husserl and Meadow Ponti and people like that. Really, it's just for me a way of drawing attention to the properties of experience. So if we talk about, let's say, visual perception,
So perception here is how my brain interprets visual sensory data to form representations of the world outside. And you can think of that as having like a functional aspect. So what does perceiving things visually allow me to do? How do I behave with respect to visual information? But there's also a phenomenological aspect. There's how visual experience is seen, the experience of redness,
is different from the experience of, let's say, an object in vision. An object seems to have a back, even though I can't see the back. There's a phenomenology of objecthood. There's a phenomenology of spatiality. All my visual experiences have a spatial character, things organized in space in a way that, let's say, smell doesn't have so much. Emotions have a very different kind of phenomenology.
And emotion feels different from any kind of visual experience. So I use phenomenology just as a way of thinking about what a science of consciousness should explain. What I think a science of consciousness should explain are phenomenological properties. Properties of experience. Why redness is the way it is in our experience and is different from an emotion or is different from a smell or a memory. That's what I mean by phenomenology. And when you say explain,
Part of the problem with consciousness are at least people who are less scientifically minded, who are disinclined to believe that consciousness can be studied materialistically. I think part of the issue is what it means to explain consciousness, what it means to explain any phenomena. So when you say we're trying to get an account of consciousness, do you just mean correlates? It's a very good question. I think there's a lot of
Ambiguity and confusion about what explanation means. I mean, whole books have been written about what explanation means in science. There's a beautiful book by Karl Kraver called explanation in neuroscience, which is anything in neuroscience. What does it mean to have an explanation of it? The way I think about it is an explanation in consciousness science
does not have to solve the whole problem that we come up with this intuitive eureka moment about now I understand how the electrochemical pate inside my skull gives rise to the redness of red. That would be nice, but we can have explanations that are relevant without that kind of big ticket prize. So by explanation, I mean more than correlation, and that's key. So
It's already a relatively standard method in neuroscience to look at the brain and see what changes in the brain as different aspects of consciousness change. What happens in the brain when you fall asleep or when you go into general anesthesia or what happens in the brain when you consciously perceive a scene versus you still respond to it but you know you're not conscious of it. So this is a standard method which is looking for the neural correlates of consciousness.
Just finding correlations is not sufficient for explanations. Correlations provide constraints on explanations, but they don't provide explanations themselves. To explain something, what you want to have is in some way the correlation is no longer arbitrary. You want to have a sense that, ah, yeah, I see why that correlation obtains because it explains something about the thing it correlates with.
Which for me means that the right way to think about this in terms of the brain and consciousness is not going to be so much this part of the brain is correlated with consciousness and this part isn't. It's going to be at a sort of intermediate level. Consciousness correlates with this kind of process, these kinds of dynamics in the brain, because they have similar properties that the conscious experience has. So we need a more kind of thinnest
bridge between what's happening in the brain and what's happening in experience. And if I can come up with something in the brain that tells me, oh, that's why consciousness in this case is the way it is and not some other way, then that's an explanation. In science in general, we judge the success of science, the scientific field,
Usually if it can explain something, if it can predict when things are going to happen and if you can control those things. Explanation, prediction and control are good criteria for the success of science. And I think we should apply those same criteria in this case too. This doesn't mean that it has to be intuitive. Quantum physics is extremely counterintuitive, but in terms of explaining phenomena, predicting and controlling, it's extremely good.
So this leaves open that we might come up with a good theory of consciousness. And it might do the job of explanation, prediction and control, but we might never get the feeling that like, oh yeah, that's right. Now it all makes sense. This might not happen. Don't know yet. Let's take quantum mechanics as an example. The way that I
view it as it's more instrumental people who are studying quantum physics they're hesitant to say that it's an explanation they're more apt to say it's a model and it provides some predictions and it's an operationalist approach some people might take a more philosophical bend and say you know this is an explanation but truly truly i don't it's difficult to be a scientist and not be an instrumentalist and if you're an instrumentalist you're not
It depends on what you mean by explain. Is the fact that you can write equations that predict a certain number and then you find it in the data, does that mean that you've explained it? Well, I don't know. I don't know if that matches what people consider to be an explanation. But explanation is a tricky word to define. OK, now how's this related to the real problem? You mentioned that there's a hard problem, there's the easy problem, and then there's the real problem. That's your ante.
So I'm curious, is what you just described the real problem and how does that delineate from the heart problem? Yeah, that's basically it. So again, this is a little bit fast and loose with these terms that are used in philosophy. So the heart problem has been one of the classic go-to's in people thinking about consciousness from a philosophical or neuroscientific perspective. It's due primarily to David Chalmers and the Australian philosopher. And he describes the heart problem of consciousness
It's this metaphysical problem, really. It's the idea that even if we had a complete description of how the brain as a mechanism worked, how it transforms sensory signals into actions, into our behavior, if we understood everything about the brain as a physical, chemical mechanism, there would still be a mystery about why and how any of that activity
should give rise to a conscious experience. Very broadly, why is consciousness part of our universe at all? How does it relate to the operation of physical stuff? That's the hard problem. And it is a very metaphysically loaded problem. It's really a question about the capabilities and limitations of physical explanations, explanations in terms of mechanisms.
And it articulates the intuition that consciousness is somehow beyond the limits of physicalist and mechanistic explanation. Now, there's all this debate in philosophy and neuroscience about whether the hard problem exists, whether it's an illusion or whether it can in fact be solved.
I put my cars on the table, we'll want to remain agnostic about that. I'm not sure whether the hard problem is a real problem that can or cannot be solved. But what I do think is that we can still ask questions about consciousness without sweeping it under the carpet entirely. So the easy problems are again, in Chandler's distinction, these are the problems that
don't really appeal to consciousness at all. They're questions about how the brain works as a mechanism, how it can explain perception, sure, but any kind of perception, action, attention, behavior, language. But we can answer all the easy questions without referring to consciousness. Now, there's, I think, an enormously rich middle ground, which is to appreciate that conscious experiences exist. Let's assume that they do and
We have experiences of color, of shape, of emotion, all sorts of things. And we can start to try to explain the properties of these conscious experiences in terms of mechanisms. This is exactly what we were talking about. Can I explain why a visual experience is the way it is and is different from, let's say, an emotional experience in terms of brain mechanisms?
And if I can do that, I think I'm making progress on the scientific explanations of consciousness, even if I'm not going directly after the heart problem. Now, other people have expressed pretty similar ideas. Chalmers himself called the this approach something like the mapping problem, how to build non-arbitrary correlations between things in the brain and things in the world of our experience. Other people have talked about neurophenomenology. This goes back to Francisco Varela in particular.
Just pretty much the same thing again, how do we link things happening in the brain to things happening in our experience? So there's a tradition of thinking this way. Do you see that the okay for us? Yeah, sorry, I just wanted to talk about the role of perception in all this because
I find the way you have described in the past the perception's relationship with reality quite fascinating. You have previously said before that, famously in a way, you have said that normal perception is controlled hallucinations. Now, this idea of hallucination or illusion, I suppose first of all, do you distinguish between these two words, hallucination and illusion, or can we use them interchangeably?
Maybe you can answer this and then I have a follow-up question to this. Sure. I mean, well, let me first say that I think it's a lovely phrase, perception is controlled hallucination. I certainly didn't come up with it. I heard it from one of my mentors, Chris Frith, who heard it somewhere else. And actually a few of us, we've tried to find out the proper origin of it. And I've never been able to. Sort of there's this legendary seminar, UCSD, sometime in 1990.
which people refer to, but it was never recorded and it's just, so who knows? Anyway, the phrase does the rounds, but I think it's a good phrase and we'll get onto hallucinations in more detail, I'm sure, in a bit. I'm not sure I would use it interchangeably with illusion. Illusion, I think, is a very problematic word too, because illusion sort of implies that there is
In the context perception that there is a non illusory perception that there's such a thing one might call veridical perception, which is the sort of we're seeing the world as it really is. And when we're hallucinating or experiencing an illusion, then we're not seeing the world as it really is. But my view on this is we never see the world as it really is. Everything that we perceive is consciously experienced
in our perceptual work is a construction that's only indirectly related to what's actually there. It's just that the degree to which these perceptions are constrained by what's actually there differs. So I think illusion for me, and I'm thinking about this now really for the first time to how I would distinguish it. Illusion is probably a very systematic
relationship between what's there and what we perceive that is not necessarily maladaptive. It can often be just useful. It's sort of a quirk of the visual system where a normal way of constructing our perceptions is revealed to be quirky in some way. And then hallucination is something a little bit more unusual. Hallucination usually means that I'm having an experience that you're not.
or that other people aren't. And it is no longer adaptive in that same way, no longer necessarily so useful. But I wouldn't say it's a hard and fast distinction. If you look at, for instance, if we look at fluffy clouds and see faces in clouds, then this is probably something many of us do. And you could equally call that an illusion or a hallucination. And strictly the word for that is the Greek term pareidolia, seeing patterns in things.
So I think there's interesting sort of landscape of these terms. Right. And then to follow up to this idea, I mean, the general population might think that, for example, illusions are in a way negative limitations that might prevent us from reaching the supposedly noble goal of, for example, searching for the truth, let's say. Right. But, you know, you and others such as, let's say, Donald Hoffman, you've
brilliantly argued that illusions are actually could be in a way a gift for example in your talk about consciousness you bring up the Adelson's checkerboard illusion phenomenon and in a way my question with this would be that if we have pragmatically evolved in a way not to experience reality in its true form you know it's about fitness in a lot of ways from an evolutionary perspective and are better off if truth is in a way evolutionarily or perceptively
driven toward extinction, then why should we want to get to the root of reality as a whole? Isn't ignorance bliss in this specific case? There's a lot of loaded phrases there about truth. Of course, truth matters. And there are things that we can't perceive, which make a huge difference to us. If we could perceive coronavirus particles, I'm sure people would be much more willing to wear masks.
And if you go and jump in front of a bus, whether or not you're looking at it, it's going to hurt. So I'm certainly not being anti-realist about this. There's a real world out there. We don't know quite what it is. Best ask a physicist for that, what the ultimate nature of reality is.
But it's certainly true that whatever it is, is not, we don't have and can never have direct access to it, to perception. And this is a very old point. Immanuel Kant, I think, says it, Plato said it, but Kant especially talked about the Newman and that the sort of the external objective reality that's forever hidden behind a sensory veil. So in a sense, it's an elusive goal to think that we could ever perceive
the true world in the sense of having direct perceptual access to physical reality. But what we perceive is constrained by that reality. That's what perception is all about. It's a way of constructing a world for us that is usefully constrained by whatever's really out there. And as you said, and Don Hoffman has said, a whole bunch of people have said this really, that as soon as you appreciate that
Our perceptual experience is not a direct reflection of an external objective reality. Then it's quite easy to think that, well, what we perceive is going to be tuned by evolution to what best keeps us alive. And I think there's a really deep truth to that. And you can think about it in one of the very simple examples like color. We experience colors as usually we experience them as really existing properties of objects in the world.
color seems to be a property of an external objective reality, but we know that it isn't. And we don't even need neuroscience for that. Newton has shown that color is not a thing in the physical universe. There's this whole continuous spectrum, any part of it that we were able to, that can shape our experience at all. We create this universe of colors from
The fact that our eyes are responsive to roughly three different wavelengths, but we see way more than three colors, which for me is fascinating because in one sense we are perceiving much less than what's actually out there because we don't experience X-rays or infrared or ultraviolet at all. But in another sense, we're experiencing much more than what's out there because we create a universe of colors just from combinations of three wavelengths and the brain does this.
because colors are very useful to guide our interaction with the world. They're a way for the brain, in this case, to keep track of surfaces when lighting conditions change and to distinguish between different kinds of surfaces. It's a very, very useful thing for the brain to figure out what to do. So I don't think of it as, in this case, it's not like we should
The goal should be to not experience colors anymore and experience just those three wavelengths of light. I mean, no, even though that's closer to objective reality in some way, that seems like an odd goal to have. I think that the interesting thing is just to understand much more about this relation. How do we construct the universe of color from a very limited sampling of physical reality? And why is that a useful thing for the organism to do?
I mean, one example that comes to my mind regarding this was the idea that, for example, you have an organism that might be tuned to fitness in terms of understanding small and large quantities of some resource as, let's say, one color, let's say red, and anything that is in the middle as another color. So for that specific organism, it doesn't really matter whether
that resource is in a large or small quantity. That's why it sees it as the same color. And what matters is whether it's in the exact amount that the organism needs. So in a way, evolutionarily, the organism evolves to not distinguish between small and large amounts of a quantity. And that leads to evolution in a way hiding the truth that is behind it. So that idea just
Yeah, I think there's something right about that. I know various people, Don Hoffman as well, uses this idea of the metaphor of the desktop, right? The desktop on your computer is useful because it hides all the stuff going on in the operating system that is not useful for the user of the computer to see. We just want to drag a file into a folder and be unaware of what's actually happening to make that happen. And so indeed, I think there's every reason to think that perceptual systems
Let's take this Hoffmanian argument a little further. So the argument is that there's no relationship between or there's little relationship between truth and fitness and we're tuned for fitness given that we're not seeing reality or at least we can't claim to. Now, given that, how can we ever make any claim that there is an objective world or what the characteristics of this objective world is like? Now,
You made a claim in one of your talks about misperceiving yourself, that some mental disorders can be seen as you have the wrong idea about yourself. How can you have a wrong idea that to me implies objective, but it's difficult to know the objective without making reference to adaptiveness? Okay, so I think, I don't think anybody's saying there's no relationship between truth and fitness or perception. It's just not, they're not the same thing.
So, but there's going to be some overlap. Like if my, if my perceptual system reliably represents things as far away when they're close and I try and cross the road, I'm going to get run over. And that's, that's, and so that's, that's not a good way for perceptual system to be organized. So that there is a, there is a systematic constraint between what's out there and what I perceive.
Yeah, I'm not sure if that's true. Now, let me just rub my butt, because there are ways that you can form graphs. There's something called quantum graphs. I believe it's used in loop quantum gravity. But regardless, where you can represent what's far as close and what's close as far,
And this actually Hoffman does make this argument that there is virtually no relationship between truth and fitness. One of the ways he does it, I have my objections and anyone who's listening can watch the podcast. One of the ways that he does this is by saying, let's imagine that the universe at the objective world has some property of structure. Let's say it's a group structure. Let's say it's a partially ordered set, whatever it may be. Then let's imagine the totality of the ways that you can perceive.
You find that as the complexity of the system increases, the amount that conforms with reality, now in this example I gave is a group or a partially ordered set, but there are various other structures, that the amount of ways that you conform with reality divided by the total amount of ways you can experience it goes to zero. So he may argue, now he's not here, and I could also be misrepresenting him, but he may argue that there is virtually zero relationship between what's out there and how we perceive it.
And in fact, okay, sorry, please. I mean, again, we probably would need him to see exactly where he's planting his flag. And but but I think I still suspect a slight confusion here because I would I would also I'm also of the view that and we've said this earlier that I can never perceive what is actually that that the nature of
the physical universe, assuming there is one, which is still up for grabs, right? That is something that is not directly accessible, can never be directly. Perceptual mechanisms just don't get there. That's not what they can do. So in that sense, there will always be a gap between our perception and what is there. However,
precisely because our perceptual mechanisms have been shaped by evolution they will have been shaped so as to be adaptively constrained by the regularities in the physical universe that are important for our survival which is precisely why if i'm crossing the road i will see things as far away when they are far away and as close by when they're close by i mean the other the other thing
A useful distinction here I think goes back again philosophy to Locke and the British empiricists who distinguished between primary and secondary qualities. And a primary quality for Locke is something that exists independently of a mind or of an observer. So something like having solidity and moving are properties that exist independently of a mind or an observer, which is why
If I stand in front of an onrushing bus, it's not going to go well. But then there are other properties like color, which are for lock secondary qualities because color requires the interaction between an observer or a mind and the physical universe. Suzanne also talked about this. He said color is the place where the brain and the universe meet. And so there's
at least two ways of thinking about the kinds of things that are, two ways of a way of partitioning our ontology. And they're both, but in neither case is our experience identical to whatever its hidden causes are in the world.
Whether it's a primary quality or a secondary quality, we're always constructing on the basis of those qualities or properties, we're constructing our experience. It's just that for a primary property, for a primary thing like solidity, it's going to exist whether we are conscious of it or not. But our perceptual mechanism will still be constrained by it. We will, a well-designed perceptual system
will be constrained in ways that makes us behave appropriately to these things. Right. I don't want to remain stuck on this, but I guess my objection is the notion of farness and nearness is dependent on space and space time itself. This is something Donald Hoffman likes to reference. There's a physicist named Nima Armani.
Hamed, I believe, but many physicists, almost every single physicist, believes that space-time is not fundamental, which means that location... You may say that, well, we're constrained. Constrained is not the same as... And you're definitely admitting that there's not a one-to-one relationship between reality and then how we perceive it. But then even in these examples of solidity, well,
What's solid in quantum mechanics where the wave function spreads to the universe? Sure. But there's something. OK. But firstly, I think actually you bring up a very interesting point. We're getting very deep into the weeds here. But for me, one of the most interesting things about this way of thinking about perception is how far you can take it.
and so for instance yeah i can i can perceive a color as and i can understand the perception of a colored surface in terms of an invariance in how a surface reflects light and under different lighting conditions and so on but then what about what you might call the deeper structure of perceptual experience we mentioned this right at the beginning as well the fact that visual experience is spatial that we overall tend to
experience the world in this three plus one dimensional way, in three spatial dimensions and one time dimension. Can we understand that as constructed in the same way that we would understand the experience of color as being constructed? Is our brain generating this architecture of experience through the same principles? Because yeah, from a more
physics-based perspective, you might say, well, actually, this three plus one dimensional picture is not the most accurate picture of the physical universe. And we could argue, and I would not have an expert view about what is, but I know there are many options out there. Even relativity tells you that the three plus one distinction is not as solid as our perceptual world would lead us to imagine. And then, of course, you've got string theory and also Bok universes and all sorts of stuff.
But in a sense, you can be agnostic about what that ultimate reality is, if there is such a thing, and still ask the question of, OK, so what's constructing? How do we experience time and space, not just objects within time and space? And I think, for me, that's a really exciting direction to push this kind of research. Speaking of the perception of time, I remember you said, this is obviously known, that the more adrenaline you have in your system
Let's say it peaks, you feel like time has slowed down. Well, I wasn't sure I said that. I mean, certainly there's just this kind of popular assumption about time slowing down under various sorts of high arousal situations. And actually time here is something that I've been working on just for the last four years or so. And it's really due to one of my colleagues, Warwick Roseboom, an Australian
cognitive scientists to join join the group in 2015 and brought a deep interest in a wealth of expertise on time perception. So he's been leading our work there. And one of the so one of the I think, really fascinating lines of argument that he's making, and I agree with him, it seems right is that is to push back against this idea that we
experience time in virtue of having a little clock inside the head. A lot of work in this area boils down to an assumption like that, that there's time unfolds in the world. And certainly, when we're making judgments about time, we often get it wrong. If we measure an objective duration, and then we ask people how long that duration was,
People can be wrong about it. And they're systematically wrong in the same way they're systematically wrong about many other things in perception. And for instance, there's a very general law in perceptual psychophysics where people are biased towards the mean of the things they're judging perceptually. If you see a whole load of circles of different size,
and then you're asked to judge the size of the next circle. You'll be biased towards the mean of the circles that you've already seen. It's called regression to the mean. And in time perception, you do exactly the same. If you experience a load of different durations, let's say just beeps of different lengths, and you're judging the duration of each beep, you'll be biased towards the mean. And this is a very useful signature that
There's something like Bayesian inference going on here, that your perceptual judgment about a situation is based not only on the sensory data, but on your prior expectations.
about what's going on. Bayesian inference is simply this way of combining what you already know with what new information you have to come up with a best guess. When you say that we're biased toward the mean, do you mean that of what we experience first? So it's like we take a sample of our first experience and take the mean of that and then our later experiences are then biased toward that mean? Or do you mean we're biased toward the totality of the experiences means? Well, this is a good empirical question, right? It might depend. So
It probably depends on the details of the experiment over what time scale the brain is taking the mean and it's going to vary by task, by context and so on. In this case, I was really talking about fairly short time scales where you can show that you're just on the last one or two minutes of what's going on, then you'll be biased in your next decision.
towards basically the mean of that. But then you could make the argument, although it's much harder to demonstrate empirically, that for instance maybe my experience of duration in general is biased by the mean of every experience that I've had and my ancestors have had and so on. But of course I can't manipulate that in the lab. So in the lab I can only manipulate context over relatively short time scales and see what the effect is. But this is a very circuitous route to this idea of
of time slowing down and so firstly for me there's a very interesting distinction here between perception of duration and the experience of the flow of time that's interesting so there's a difference between those two yeah i think that is it's
We can perceive something as lasting a certain duration, but the experience of just how fast time is going is different. It's different in this, again, in perception in general, we can separate the change of perception from the perception of change. So, I can experience my perceptions having changed, but then the experience of the change is itself a kind of perception.
There are various phenomena, things like change blindness, which show this very nicely that if something, if I'm watching just like an image, which I'm assuming is not changing, but actually maybe the background color changes very slowly, you'll find that people won't notice that change. And sometimes people say there's a paradox here because
They didn't notice that change, but they're now looking at a different thing. So how does that work? And I think that the resolution is to say, well, no, that perception has changed, but they didn't perceive the change because change of perception is not the same as perception of change. So I think the similar thing plays out in time as well. That perception of duration is not the same thing as the perceiving time flowing. And it's much harder to to get an empirical handle on
The Flow of Time, my favorite experiment here. I don't know if you've come across this by a guy called David Eagleman and Chet Stetson, I think, was his researcher at the time. And so they had this idea that if indeed my perception of time is slowing down at moments of high arousal, so let's go back to that. How can I test that? Well, so they sort of thought, well, if time is
Slowing down then maybe if I do have some sort of internal hear that sound
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The clock that's the ticking of which is underwriting this perception then maybe there are more ticks of the clock going on in a particular objective duration so then I would experience time is dilated and so that was the reasoning and so to test it he had this beautiful experiment where he gave people watches that were specially designed so they would flash numbers
But so quickly that if you just looked at them now, you just see a blur. You wouldn't be able to decipher what the numbers or the letters were. And so he then had people bungee jump while looking at this watch several times, then go to the crane, look at the watch. And the hypothesis was, well, if subjective time is slowing down because an inner clock is increasing its rate,
This frame, right? Let's say, then maybe these people should be able to read what's being passed. What do you think happened? I would imagine they did. Right. No, they didn't. No, so it was a really interesting failed experiment. I mean, it wasn't failed because the evidence was pretty clear, but it ruled out that simple explanation that, yeah, this clock is speeding up. Because people subjectively still had experienced
So that's super interesting to me, because to me it sounds like what you're saying is we can be wrong about our own perceptions. For example, OK, or I'm posing this as a question. Can I say I see this cup as red? I see. Sorry, let's look at this. I see this as blue.
I see this cup is blue. Could I be wrong about my own perceptions? I think I see it as blue, but is it possible? Like in the example of these people who say that time has slowed down, but they're wrong about that. Can I be wrong about seeing this as blue? Now, in fact, you know, with our shared reality, this you can may be able to objectively measure it as blue. Can I be wrong about my perceptions?
I think there's at least two very interesting responses to that. Philosophers often talk about the ineffability of conscious experiences, this idea that we can't be wrong. If I'm in sharp pain now, that's just a fact and I can't be wrong about it. When I think about claims like that, the first thing is
One problem is a sort of epistemological problem, like how would you know? When the claim is about a subjective experience, what's the right way to validate that against? So does it even make sense as a question being wrong about your own experience? But what might it mean? It might mean that you are wrong in your interpretation about it. And I think that's usually what people mean when they say that
They're wrong about their perception. They might say that, for instance, I experienced time is slowing down. But then if you actually look at how they estimated the duration of something, it may be basically the same as in another case. So they are
you write in the sense that they're giving a sort of face validity you know what they're experiencing but all the ways one might interpret that might might be wrong take another another very i think illustrative example um people for thousands of years have reported out of body experiences they'll have experiences where they're
floating above their physical body or floating around a roof or going out the window, whatever. Are they wrong about their experiences? Well, in one sense, no. If that's the experience they're having, and they're not just sort of confabulating it later on, then that's the experience they're having. But
If they interpret that experience as evidence that their self has in fact left their skull and gone flying around, then they're wrong. That's not the right way to interpret those kinds of experiences. Or rather, there are plenty of other options by which you might interpret those kinds of experiences. And you can also be wrong
just in the small space that opens up between the moment of your experience and the moment of your report. And if I tell you what I'm experiencing, I have to remember it, even if it's only for a very short time. And you could be misremembering. You can systematically misremember stuff. There are many ways where we can introduce
introduce indirectness between your experience and your report of that experience. So you can be wrong in that sense too, I think. But there is something for me that it almost doesn't make sense to ask the question, can I be wrong about my experience in the here and now, bracketing all these things about interpretation and report, because there's no criteria to judge it against apart from the experience itself. Yeah, for us,
If I may, because this is one of the questions I had in mind, which ties really nicely into this. You most likely know about Jill Bolte-Taylor's famous TED Talk, the stroke of insight, the one where she goes into detail about her experience of having a hemorrhagic stroke on the left side of her brain. And then she experiences these feelings of euphoria. She goes into the state of nirvana because the way she's describing it, she thinks her
the right side of her brain is sort of taking over. And then once her left brain comes back again, then suddenly she comes back to her version of the version of reality that we experience and she realizes, okay, something's wrong. I have to go get some help. And that talk generally was really fascinating to me, but I just wanted to know your thoughts on that kind of experience. And maybe we can follow up with the idea of, from a neuroscientific perspective, the left and right brain
I suppose my question is twofold. One is what are your thoughts on the way she was describing that out-of-body experience, in a way you could call it an out-of-body experience, and secondly, the distinction between left and right brain.
Yeah, I don't have too much to say about the first one, about the sort of experience of bliss or nirvana. Again, people do report these kinds of experiences in various conditions. There are examples, what comes to my mind are these examples of so-called ecstatic seizures. So some people with epilepsy
experience reliably these moments of bliss and awe and presence of the numinous and all sorts of wonderful experiences, either in the penumbra or the periphery of their seizures or maybe even during the seizures, I'm not entirely sure, to the extent that sometimes they don't want to be medicated or they don't want to be relieved from their seizures because they get
this from them. Quite what's going on for these sorts of experiences is extremely hard to say, I think. And the part of the problem is, it's been extremely difficult to investigate them in controlled conditions in the lab where you can actually see, okay, this is what's going on. Is it a wash of a particular kind of neurochemical activity in this or that part of the brain? It's unclear. So some of the stuff from epilepsy shows that these
Some brain regions seem to be more implicated than others, but I wouldn't want to put too much stock in those. But it's a fascinating class of experience. Sure. And I think, again, there's a lot of, certainly a lot of interest and there has been a lot of activity for ages about the neuroscience of meditative experiences. It doesn't have quite the same end point, but certainly there are examples of people in
meditative states who will experience the dissolution of the self and the ego and so it's kind of fascinating to see back to where we started. So what in the brain can explain that kind of phenomenology, that kind of dissolution? An open question. The second thing about laterality in the brain left versus right hemisphere and this is
It's a huge, it's a, as other than most people will know, we hear these tropes and these cultural tropes about the left brain being analytical and the right brain being holistic and artistic and left brain. And as with all these things, there's a grain of truth underlying this, but it's only a grain. And pretty much for everything you do, the both hemispheres of the brain are working together. Some things are more lateralized than others.
And so this is a few of these things, a couple of these things. When you get more towards output and input, things tend to get more lateralized. So if you have a stroke in one half of your visual cortex, that will affect one half of your visual field. If you have a stroke in your right hemisphere, your motor cortex will be paralysed on your left hand side. So these things are very lateralized. And that's not particularly mysterious.
So most of the time, it's working together. I think the super interesting studies here, I don't really like very much this habit of
describing people as left-brained or right-brained. I think that's some kind of neophrenology stuff. But what's still really interesting are these old case series, these neurosurgical case series of people with what we call calisotomies. These are people who've had split brain operations. This used to be done
It's pretty rare now because other medications become more effective. But for people with really, really severe and intractable epilepsy, one of the options was to cut all the majority of the fibers connecting the two hemispheres, hence the term split brain. And there's some absolutely fascinating observations. This goes back to people like Mike Gesaniga and Joe Bogan, someone who would
This would give the two hemispheres different input to try and ask the question, are there two separate conscious subjects now, now that you've split the brain like this? And there are very suggestive hints that there's something weird going on. You can show, I always get my left right mixed up because so many things cross over here. It's very hard to keep straight about it. But if I show my, hold on, this has to be my,
Right visual. Right. Forget about the location. Anyway, if information gets into my right visual cortex that doesn't get into my left, then typically the person is not able to verbally say what that is because the left language side doesn't have access, but will maybe try to confabulate what's going on.
So the right hand side might still be able to draw what they see. And then the left hand side will make up some story to justify why the right hand has drawn it. And so these are, these are really, really super suggestive, but it's still never been entirely clear. This basic question of are there two, have you, have you divided one person into two or not? Because a lot of the early studies,
turned out to have been methodologically limited in various ways. And so now with sort of more modern methods in the few patients that are still around, perception does seem to be more integrated across the visual field than we would have thought. But to me, it's still a fascinating case about could we divide a single conscious person into two conscious people? And what would it be like to be one or other half?
Yeah, so just to clarify one point then about it, the idea that, for example, the right brain, as she was describing in this way, where she sort of, when the right brain was coming into
into effect, she felt like she was connected to everything around her. She no longer felt like an individual. She felt like she was everything. And she describes it as the we sort of experience. And then when the left side comes back in, that's where the individual self comes back on. Now, this definitely sounds like a really interesting analogy, dichotomy, that sort of thing. But I just was wondering from a neuroscientific perspective how much truth
exists here and whether we have any evidence of this I versus we sort of distinction. Well, I think there's certainly there is a distinction between or rather the experience of being as an individual separate from others and from the world is something that varies and it varies for each of us at times. If you're fully immersed in something, you tend to experience yourself as
less separate from them. And people call this sometimes by the term flow experience. If you're in a crowd dancing or a football game, you feel part of the crowd. And that's not just a metaphor. It picks out, I think, a valid aspect of your experience of reduced individuality at that time. People on LSD, that's also one of the classic
reports from psychedelic experiences is a dissolution of the ego and a feeling of connectedness not now not just with other people but with the with nature with the world and So that you know all these things together suggest that well, there's a brain basis for the strength of our experience of individuality and
But I don't think it comes down to simply right brain versus left brain at all. I see. And just so that I can go back to one of your other statements that I found really interesting, you mentioned, please correct me if I'm wrong, you mentioned that an object would exist regardless of whether we perceive it or not. I believe that's what you said. I'm wondering how this ties to John Wheeler's ideas
regarding, for example, he makes an assertion in the sense that a conscious observer is a necessity in order for us to declare that something exists. Without the conscious observer, it's like part of a formula that without it, if we remove it, we cannot make any claims whatsoever about whether something exists or not.
So how does the idea that you brought up tie into that? Do you agree or disagree with that? Well, you said two separate things, though, which were different. So one is what are the conditions for something to exist? And the other was what are the conditions for us making claims that something exists? And I think if it's the second, then observer is probably needed. You can't make an inference about an existence without an inferrer. But whether there are objects,
whether objecthood or intrinsically requires observer that that's again that's it I think that's a it's a deeply physical metaphysical question so John Wheeler who you mentioned is I mean I always associate him with this idea of of giving information some real status and ontological status and he's famous for the slogan it from bit that everything that we
measure, whether it's using the tools of science and physics or experience, fundamentally, our universe is written in the language of information. And then, you know, from that, then there's all sorts of ways of understanding that that kind of claim, because some sorts of informational relationships are fundamentally relative. Shannon information, we can think of that way. It's a sort of
depends on a sender and a receiver. Other ways of thinking don't, but to me that's now, that's a sort of, I'm not trying to dismiss the interest of these things. I think that they're fascinating and actually they do play into how we might read certain contemporary theories and consciousness science in particular, things like integrated information theory from Giulio Tononi. Then it makes a big difference what you think information is.
What do you think it's, if you're with Wheeler or not? But for the most part, I don't think what I was saying about objects, you know, I want to bracket those discussions away from that. And it may be true that in some physics-based way that we can't say anything exists unless there's an observer, but
For the story I'm trying to tell, which is just this idea that what we perceive is always a construction, but underlying that construction, there are hidden causes that we can never directly have access to. I think that stands whatever you think about the ontological status of information. You're just looking at it at a different level in a way. These are distinct levels that
might make sense on one aspect, but not on the other. That makes sense. What are your views on the Sapier-Whorf hypothesis? Now it really does feel like an interview, like bang, bang, one hard question, another. Oh, and just, okay, you can gather your thoughts on that, just as an aside, because this bothers me. I'm not a theoretical physicist, but my background is in theoretical physics.
When people make claims of consciousness being associated with the observer and quantum mechanics, much of that is over exaggerated and taken up by the new age community because they tend to like to use the word consciousness and tend to want it to have some ontological foundational status. And it might be, that might actually be the case, but it's over exaggerated and it's extremely contentious. And I believe something like 90% of physicists don't believe that to be the case. The way function can collapse when there's another electron or another set of electrons,
Objective quality like atoms observing another photon then you can collapse the photon and but even that's a bit That's a bit that has to be stated more technically because there's something called coherence and decoherence Either way take those claims that the conscious observer is necessary for the collapse of a wave function with a grain of salt Absolutely, I mean and you guys gonna know much more about physics I mean I started off in physics, but I
I switched to psychology when physics became too hard. I'm super interested in your background, man, because you also went back to do a computer science master's and an artificial intelligence PhD, if I'm correct. Yeah, that's right. Yeah. Okay. That's super cool. Well, we'll talk about that after. So let's talk about Sapir-Whorf. Okay, so Sapir-Whorf hypothesis is really is this idea that language either determines or shapes perception that
that the linguistic environment we live in influences the perceptual environment that we live in, I think is probably one way to say it. Technically, people will talk about cognitive penetrability here, that is the way we see the world or hear it or smell it. Is that invaded by higher level beliefs?
cognitive processes of which language is exemplary. So the Sapir-Wolf hypothesis is that, yes, that the language that we use shapes the way we perceive it. And this can be, you know, this can be in kind of sort of subtle ways, like, how do I perceive time? Is that dependent on the way I use
language. There are all sorts of lots of interesting anthropological experiments looking for languages where, for instance, in Western languages, we tend to think of the future as ahead of us and the past as behind us. But I think it's the Aymara. This is something I was very secondhand on. But there's reports of some indigenous South American cultures
For which it's the other way around. Language is for which the other way around. That the past is ahead of you and the future is behind you. The reason being kind of makes sense to me is that, well, you know, you can see the past. You know, I know what happened in the past. It's happened. So therefore it's within my line of sight. But the future is unknown. I don't know what's going to happen. So I can't see it. So it's behind me. So these... But would that linguistic difference
that sort of metaphorically shapes how we talk about time, but might it actually influence the way we perceive time? So there are all sorts of interesting questions about how deep these influences might go. To me, it's sort of a priority that I'd be surprised if the Sapir-Whorf hypothesis is not true. Right. That's my instinct. People seem to find it appealing, I think, is because of this
this idea that there's this modularity in the brain, that we have perception, which is some sort of encapsulated at some lower level, we form this perceptual representation of the world, and then we think about it, and we talk about it, and we make decisions about it, and then we go and we do stuff, we make a plan for what I'm going to do next, we do stuff, and then we perceive the world again. But the brain doesn't work like that, I don't think. And what you were describing was a bottom up approach?
Well, it's sort of more just an approach of extreme modularity. So people like Jerry Fodor is known for this view that one of the longest running arguments in neuroscience has always been about functional localization. To what extent of different things the brain does localize different brain regions. And the pendulum has swung back and forth on this. Obviously, both extremes of
can be ruled out to start with you can't have a brain where bits different bits do different things and don't talk to any other bits. And you can there would be no point to that because you'd have no cross communication anyway. Right, exactly. And you can almost equally rule out the other extreme, although you can't quite rule that conceptually, but certainly, empirically, it's ruled out very quickly, you have damaged different bits of the brain, different things go wrong. And
But you can still, but there's still a more subtle level, there's still this argument about the degree to which functions, let's say a function like language, is just served by a particular network or brain region. And so those bits of the brain do language. Yes, they talk to other bits of the brain, but they don't sort of bleed over into those other bits.
Computers like this laptop computer is kind of modular in this way that you know, there's a chip that does memory a chip. That's the CPU Chip that's the IO ports and so on you can replace these somewhat interchangeably So it's pretty modular that so this kind of design is a reasonable way to design systems Many of our technology design this way that typically biological systems don't end up being designed this way and if we look at
Now that we know a bit more about how things like visual perception unfold in the brain, they're not limited to just the visual cortex. So the way I and many others think about perception is that it's this hierarchical set of predictions about the causes of sensory inputs. Many of these happen in visual cortex, but some of them happen outside of visual cortex. So
things like language will interact with visual cortex in interpreting, coming to the best guess of the causes of sensory inputs. And there's a lot of experiments now. There's a great paper by Gary Lupien. I think he's at University of Madison, Wisconsin. He sort of took this debate more into the realm of experiment and just
summarise a load of evidence showing that words influence perception in pretty clear ways. So this to me is not surprising, but it's also there's just there's lots of interesting questions about how far this goes. Again, this is always a question. How deep do these influences go? What kinds of things are are amenable or influenceable by things like language?
It seems like there's a controversy around it when you even just look at the Wikipedia article about the Sapir-Whorf hypothesis. Pinker and Chomsky are both against it being true, and I haven't had a chance to look up their arguments. I'm curious if you could explain to me, as well as the audience, what are Chomsky's, and to a lesser extent Pinker's, but I'm more interested in Chomsky's, arguments against it. Yeah, to be honest, it's not something I've studied much either. My feeling is that
I mean, Chomsky is known for his ideas about universal grammar. I mean, he's such an interesting character because he in many ways put the nail in the coffin of behaviorism. So saying that, okay, we need to take mental internal mental processes seriously. And we can't just infer them always just on the basis of behaviors. We need to we need to assume some complex internal mechanism. Of course, he was doing this in the in the domain of language. And
saying you can't explain linguistic behavior purely from a behaviorist perspective on what people say, just how quickly human beings learn language, there's just, he would say that there's not enough information in the stimuli that babies are exposed to for them to infer grammar. And people still will argue about that, you know, they'll say, well, actually, there is, and it just depends on because they're interacting with it. And so I'm not a linguist, I don't want to come down on
one side or other there. But Chomsky's view became this idea of this sort of language acquisition device, this very, very circumscribed system in the brain that was for language. And so I think if you take that perspective, you are, you're going to be disinclined to the Sapir-Wolf hypothesis, which is really motivated by an idea that there isn't this kind of modularity in the brain, that
There is to some extent, there's specialisation, but there's not a complete kind of encapsulation.
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When you brought up the idea of the visual cortex being related to other areas of the brain, what that reminded me of was the... I believe there was a study that they conducted with regards to color detection being tied to
If in the language that that individual spoke, there were actual words that would define a certain color, then that individual was capable of identifying that specific color. But if a language did not have that specific color, it hadn't been developed in that language and that person would not be able to detect it.
I'm just wondering what... This is sort of a piece of evidence, right? That sort of connects. Yeah, that's a good... another piece of evidence sort of in favor of Sapir Orf, right? Exactly. And I think that the example that comes to mind when you talk about that, I think it's Russian, right? And I don't speak Russian, but I believe Russian has more words for blue than English. Maybe, maybe. And colors, you can test this really nicely with color because
Colors is a beautiful example of categorical perception. You have a continuous wavelength that we typically experience as a number of discrete colors with bits of blurry boundary. What happens when you look at a rainbow? I mean, that's what you see, even though the color is, the spectrum is continuously changing. So to assess categorical perception, you sort of ask, you present people with differences on this continuous scale and ask them to judge how far apart they are.
Their judgment changes quite a lot at some times, but not other times, then you then you infer, oh, there's a category boundary there. And so, yeah, I think this is again, for me, it's a bit secondhand, but I'm prepared to accept that people who who learn Russian from birth, I don't know about if you learn it as a second language, may divide their experiences of blue into more categories than
People who have a different linguistic environment. Against me, it's like, okay, this is kind of fine. I don't... Well, for me, it shouldn't be a controversial perspective to adopt because I think this is how perception works in general. We also notice for things like, let's say, wine tasting. You... Initially, all wines, all red wines basically taste the same.
And then as you learn, you sort of learn to distinguish them, but then you learn to apply different labels to different kinds of wines, and then those help scaffold your ability to distinguish them still further. The problem is you've got a sort of chicken and egg thing here. What comes first? Is it that you experience things differently and then label them? Or can it be the other way around? And with many of these things, I think it's probably not a good idea to seek an answer to that. It's a circular kind of causality that bootstraps these differences into existence.
Do you mind repeating that last part? Why is it that you can't start with the concept and then be able to perceive that concept afterward? So for example, I don't know the difference between cyan and turquoise and magenta and purple and their cognates. Do you know? It just looks like blue and some blue and I know green and red and so on and I could take 10 seconds to look it up and then probably solve it for the rest of my life. But either way, I see that as bluish green. I see that as purple.
Am I seeing the same as someone else, but just not noticing? And is that seeing and noticing? Yeah. Yeah. Okay. That's good. I mean, in that particular case, I don't know, we'd have to do experiments to know that, right? We'd have to, we, what we'd have to do is give these, these different colors to you and present them in sort of pairs. So you make judgments about how similar they are to each other. And then we'd have to see, are you making reliable distinctions?
between these colors that you linguistically describe as the same compared to somebody who has different words for these different colors. So I think these things all boil down to empirical questions. Now, here's one test. This might not be doable, but imagine you look at a scene and let's say it has some discriminable phenomenon that are indistinct at first because you don't have the language label for it.
cyan and turquoise for me for example and you show that to me and I just oh that's bluish or this bluish green then a day later you teach me the phenomenon of cyan and turquoise and I'm able to to discern then you put me under hypnosis to remember to remember yesterday and you say was cyan on the left or the right in other words I'm wondering
because i don't notice it initially do i also not see it does it not get recorded or does it get recorded so that i can go back later now with my proper disambiguations and disambiguate okay that's interesting i mean i like the experiment design apart from hypnosis but i think there's whichever method choose whichever method allows you to get an accurate memory it's hypnosis is real but it's not what most people think it is it's not sort of um
It's not this kind of stage. I wave a watch in front of you and you can remember your child. Anyway, but I think there's so I can indeed imagine this experiment where you make a perceptual judgment. I then give you some prior some additional knowledge. You make a judgment again and then you try and you just try and remember what what you did the first time and can you be more accurate when you're retrospectively making a judgment
given now some additional knowledge than you were at the time. There's almost certainly stuff like that has been done. I don't have it to the tip of my tongue. But yeah, that's an interesting design that could certainly address the question of... Well, I don't know quite what question it would be addressing because the problem is there's many things being conflated here. There's sort of memory
along with perception at the time. There's all these things, it really depends on what the specific question is you're trying to ask. But I think it's pretty clear, there's lots of, you know, there are lots of experiments that show indeed that expectations, what you expect to happen, can directly influence perception. These expectations can be set up by linguistic phrases, so I think there's lots of good evidence that what we think, what we
What we say that the structure of our thoughts in our language can indeed influence how we see the world. Is there a limitation to the Bayesian model of the brain? I know that it can't explain everything because there's no model that explains everything. You'd have the Holy Grail right there. And I know that you are a large proponent of
the Bayesian model of how the brain works. I'm curious, where are its limitations? I'll give you one example from my life. I was playing a video game and someone in the, I was expecting the person, I was expecting the person in the video game to say the word extinction. And I was listening, I was watching and she said something and I thought it was, she said entity instead, but I was expecting extinction. So then I rewound it and she in fact did say extinction. So I thought that was strange because I expected extinction.
She said extinction, but I heard entity. Now these are rare. But when they come up, I do write them down. Another one was I was looking for some object on my desk. Let's say it was a pen. I don't remember what it was. Let's say it was a pen. It was right here. And I didn't do a cursory glance. I looked for a second, not half a second, but a glance. And I didn't see it. And I was expecting to see it because I'm looking for it. And I looked back, and it was right where I initially looked. So there's some. OK, you understand.
Let's just take a step back and say very briefly what the Bayesian model is. Bayes' theory is just this way of reasoning with probabilities. It's this idea of inference to the best explanation. In terms of neuroscience, the idea is that that's what the brain is basically doing all the time.
perception is a best guess about the causes of sensory data. It's not a direct readout. There is sensory data. It's trying to combine prior expectations about the causes of sensory data with the sensory data to come up with the best guess. And all of these things are sort of probabilities. It provides a standard of
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The theorem in mathematics and probability theory is really telling you what the optimal way is to combine information under conditions of uncertainty. And so in one sense, it's not really
something that can be right or wrong. It's a standard of optimality. How use it to think, well, okay, that's what the brain, that's the problem the brain should be solving if we've got the cost function right. If we're assuming the brain is solving the problem we think it is, it tells you the optimal way to do it. That's one way to interpret it. Another way is more literal to say, no, this is actually what the brain is doing than the
That's a much stronger claim.
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Yeah, across people. Oh, across, well, both. I mean, I think in any given brain, it's probably not sensible to describe all the things going on in the brain as involved in implementing Bayesian inference. For the simple reason that some things can be pretty hardwired. I mean, that's one reason. There'll be other reasons too.
and one cannot but you still can probably interpret it as doing as if it were doing Bayesian inference because you can always tell a story you can always say oh yeah you know I can describe these dynamics as they're compatible with the brain doing Bayesian inference but it's a different question from whether it's actually doing it okay and again this this is actually a pretty controversial thing too that that
You can find, I think there are lots of cases where things will look like exceptions to this rule. And they may well be accepted. A very kind of basic example of this is the phenomenon of adaptation and perception. That for instance, if I show you a load of
a load of lines of that orientation, let's say 45 degrees sloping up left, let's say. And then I show you a line of a different orientation. You will perceive it as further away from what I was showing you before. This is the opposite of the regression to the mean effect that I was describing earlier. So that so I wasn't being entirely comprehensive when we were talking about that adaptation.
goes away from the mean. If you go towards the mean, that's like an example of what you would expect under Bayesian inference, because you're expecting that. So examples of perceptual adaptations seem to be anti-Bayesian, if you like. And so there's then been a lot of discussion about what that means. I mean, it's just a fact that
That's true. I mean, that's what adaptation does. And you can sort of understand it in terms of different neural populations getting fatigued or worn out. And so across the population, that's what you see. You can still tell a Bayesian story about it. I forget what it is now. But there are certainly things that it's not, I don't think the Bayesian brain hypothesis is this sort of magic solution to everything we see. But I think it's a very useful perspective
at that first level about it's a standard of optimality and I also think that a lot of perception in the brain and action can is I think probably is the brain implementing and approximating Bayesian inference. The other just last thing I want to say about that was when you were giving your counter examples of where you expected to see the pen and then it was where you were looking all along or
You expected to hear a word. There's a confusion is often made here because when people use Bayes' theory to talk about things, they will use words like expectation and belief and prediction and so on. These are not necessarily personal level things. It's not something you as a person need to believe or expect or predict. So if I talk about a Bayesian belief,
It makes as much sense to say that I as a person believe that Neil Armstrong landed on the moon, as it would make sense to say my visual cortex believes that light always comes from above. A Bayesian belief is a probability distribution, which means that it could very well be that your brain is doing Bayesian inference even though you as a person had a
expectation that turned out to be incompatible with what you see. Your visual cortex might be believing something different. I see. Can I just interject here a little bit? Is the Bayesian brain model in any way, can it be tied to mental disorders, like mood disorders, let's say severe depression? Because when we discuss ideas such as optimal,
optimal conditions well someone who is who's severely depressed clearly they're not in an optimal condition can can the Bayesian model sort of identify what what is going wrong here and perhaps alter even alter that suboptimal conscious experience any studies on that well let's first be careful because I don't want to to imply that
I mean, clearly being depressed, for instance, is not a great state to be in. So it's suboptimal for the person in terms of their lived experience. But I would worry a little bit about saying that there is a standard of optimal performance of the brain and then deviations from that are wrong and to be avoided. Optimality here simply means a sort of mathematical optimality about
the most rational way of combining sources of information that are uncertain. It can very well be that being perfectly optimal in that way is psychologically suboptimal. In fact, many people would argue that.
that we have better psychological lives and perform better if we are slightly irrationally optimistic about things. So these two things can come apart and I think there is this general worry, I have this worry about this sort of reification of things like optimality from one language to another and we suddenly start making claims about people's psychological lives and
ethics and morals and things like that. There's a big gap. Having said that, you're absolutely right that this is a good framework for thinking about phenomena in psychiatric conditions, mental illness, other things too. Perhaps the best example, one of the oldest is in schizophrenia and psychosis. And we go back to hallucinations. What is a hallucination?
In the language we've been talking about now, hallucination can be usefully thought of as a Bayesian inference where your prior belief or your visual cortex's prior belief is unusually strong. So it's overwhelming the sensory data. So the conclusion the brain comes to is guided more by what the brain expects is there than what the physical signals from the world are saying.
If you think that every perception is this balance between what we expect and what we get. Again, we had this example earlier of looking at faces in clouds. Everybody sort of has a minor hallucination going on there, partly because our brain comes preloaded with expectations to see faces everywhere. Face is a very important stimuli for us as human beings. So we see faces in clouds quite easily.
When people are having hallucinations in, well, perhaps in in psychedelia, but also in psychosis, you can think of that then as again, that perceptual predictions are overwhelming the sensory data. And I think this is this is a really powerful approach. It's Paul Fletcher in Cambridge and Chris Frith in London pioneered this this way of thinking many years ago, and
And now people like Phil Corlett at Yale are taking it further because it makes very specific predictions. If somebody with psychosis is, if their symptoms are explained by this imbalance, then you could presumably put them into a very limited psychophysical situation where we can test in a very, if you like, boring way what the balance is between their
their expectations and their perception. We can basically just, and this experiment that Phil Corlett did, was to just associate a dim flash of light with a noise, but then very occasionally leave the flash of light out and then ask people what they perceived. And people with psychosis would perceive the flash of light, report the flash of light,
more often when it wasn't there than people without psychosis because you know the interpretation being they're expecting the flash of light and that expectation stronger in these people so it actually generates the experience more often and I really like this because it if you think about how medicine works you want to get away from
defining conditions purely based on the symptoms that people report and you want to get towards understanding what the underlying mechanisms are. It used to be people would have fever and that would be their disease. You know, they have fever and maybe a yellow fever or another fever, but that was it. And you treat it by, I don't know, blood letting or something. But once you understood that,
Fever is a symptom, but there's a mechanism that's giving rise to that fever, and that's an infection. You treat the infection, fever goes away. Medicine has always progressed like that, from getting underneath the surface level symptom description to what the underlying pathology is. And in psychiatry, this is still early days. If you look at the Diagnostic Statistical Manual in psychiatry, it's basically a big list of symptoms.
And depending on what cluster of symptoms you have, that's what you got. But we're beginning to move beyond that now. And this is one example. Okay. Something like psychosis, one of the underlying abnormalities or aberrant processes is Bayesian belief updating in the brain. And that explains the symptoms, but it also means, well, maybe there are more targeted ways to develop
prognosis or therapy even. And so I think this is this is the whole area which we which is now called by computational psychiatry coming up with computational models of the symptoms in psychiatric conditions. So psychosis, schizophrenia is one. But then people also thinking about this in terms of things like depression as well, and also things which which I would rather label as
neurodiversity rather than psychiatric disorders, but things like autism, so conditions that are not psychiatric problems, but certainly involve people having different kinds of experiences. And again, what's actually underlying the surface level phenomena here, I can see how depression and psychosis might be related to a miscalibration of the Bayesian priors. How
What about other psychiatric conditions, like you mentioned autism? That one, I don't see how it's a mistake in how they're viewing the world. It seems to me to be more hardwired. Well, this is going to be clear that I don't think it should be described as a psychiatric condition autism. I think it's an example of neurodiversity. And so it's again, I think it is a very interesting example, because
typically when people are given the diagnosis or label of autism or being autism spectrum, it's often when some social difficulties become apparent. And so people typically have thought of it in terms of an issue with theory of mind that there's a difference in autistic people about the way in which they perceive the states of other people's minds.
And that's been for a long time, sort of the general understanding of what autism is. But then if you look more carefully, closely, and people have always done this, because about what people with autism report about their lived experience, it's not just about theory of mind or anything like that.
There are some very basic perceptual phenomena happening too. There's often this sensation of being overwhelmed by sensory data. Everything seems overwhelming in the sensory world. Loud noises are very disturbing. There's a sort of need to control, to make inputs more predictable. Things seem more unpredictable. And to me this, and to others, this begins to speak to
something going on that can be more usefully articulated in a sort of Bayesian language here. The brains of autistic people, they're dealing with uncertainty in a different way. They're not adapting to changing probabilities quite so well. There's a lot of hypotheses out there. The basic point is that we can again go much deeper than
how these conditions superficially present themselves to understand, well, there's something more basic going on about how these brains are processing sensory information that then these high level phenomena are built upon. Back to schizophrenia, actually, a lot of the symptoms of schizophrenia become clinically relevant when they become delusions, when people start having false beliefs about paranoia and
being controlled by the CIA or something like that. But these false beliefs can be understood as higher order inferences to explain away unusual perceptions. And so it's the perception that comes first, not the belief. And so you begin to understand that the primary pathology in something like schizophrenia is an alteration in perceptual ability. And that only then, later on as the condition progresses, does that
Does that become manifested in beliefs, in different kinds of beliefs? Speaking of, well, not speaking of, let's take attention. Gödel's incompleteness theorem. I'm curious to know what you see as the applicability or non-applicability of it with regard to how the brain operates. So someone like Penrose or Lucas would say that it implies that the brain is not purely computational in the way that we imagine computation, let's say in a Turing sense.
because of so-and-so. I'm sure you know the argument. What do you see? What does Gödel's Incompleteness Theorem has? I don't think it has that much relevance, to be honest. I remember reading Penrose's book, The Empress in the Mind, about 30 years ago now, I think shortly after it came out, just at the beginning, when I was just about to go to college, waiting for this enlightenment about why it was
going to be relevant. And it's clearly a very important piece of mathematical philosophy, right? It's telling us that there are axioms with any given formal system that cannot be proven to be true within that formal system. And as I understand it was a sort of big blow against the Hilbert program of trying to bring closure to the mathematical explanations. And
But quite what that has to say about the brain, I've never been convinced that it has that much to say. And this is partly because, you know, I don't think the brain is a computer. And so the fact that
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Sorry.
I guess for me, Gödel's theorem, if you apply it to the brain, it may tell you that the brain is not a computer. On the reasoning that there are things that we can understand to be true.
within a formal system where a proof of that doesn't necessarily exist. This is going way back because it's been a long time since I've thought about this, but firstly that doesn't seem that surprising because even if the brain were
a computer of this sort. We don't know quite exactly what kind of computer it is, so we don't quite know what sorts of true statements should be not establishable by the kind of computer that the brain might happen to be. But basically, I'm kind of happy with the idea that the brain is not a
does not operate according to these principles of logic, and that it doesn't reach true conclusions about truths by combining these logical operations in a particular way that Gödel's theorem rests on. Gödel's theorem is a sort of deduction, I think, isn't it? It's a real strong form of logic.
That's fine. Does that put you at odds with some of your colleagues? Because as far as I understand, most of them believe that the brain is some computational device that could be wrong, could just have it by a set. No, I think you're right. I think that I don't know if it sets at odds, but but I, but well, I mean, firstly, I don't think it particularly the whole point about Goodell's theorem for Penrose is then made a claim about consciousness. Yeah. And that was a connection that was, to be honest, never very clear to me.
It's sort of the idea that we consciously experience things that as being true or false, that we know cannot be proven that way by a system of logic through Gödel's theorem. So therefore consciousness is not a property of these kinds of formal systems. Again, fine, right?
It still might be the case that the brain does do some information processing. It still might be the case that it is just of a constrained or restricted kind. So I think you can have that. You can accept that the brain is an information processing device, but maybe it doesn't have the kind of class of universality for which Gödel's theorem becomes relevant. Not all computers have to be universal.
But I do also worry that people use that language too loosely when they talk about the brain. It's a very easy thing to say that the brain processes information and that consciousness is a form of information processing of some sort that we just don't quite understand yet. Maybe, but... It speaks to mind uploading.
Well, yeah, I mean, it's, to be honest, I think there's this, it's quite a big assumption that consciousness is to do with information processing and the brain is actually an organ of information processing. Yes, there is an indirectness between what sensory inputs do when they impact our retinas and our things and what the organism as a whole does.
You can always apply information processing metaphorically. You can describe a system from a third person perspective as processing information. It's transforming inputs into outputs. We can describe inputs, we can describe outputs. And there's an indirect relate. But is that what the brain is actually doing? Is it exchanging symbols in some way? How is its mechanism actually working? Or is it just a very complicated bunch of levers and pulleys?
that look as if it's processing information. Does that difference make a difference? I think it does when you draw these kinds of implications from it. So as you just mentioned, if you believe that consciousness is a property of a particular form of information processing, then you might believe
that it doesn't matter what the substrate of that is, what is the physical mechanism that's underpinning this information processing. And you're not convinced that it's substrate independent? No, I'm not convinced. But I'm again, I'm disappointingly agnostic about it, right? I actually, I think that the only conscious, the only systems we know of confident in that are conscious are biological systems.
It's difficult to come up with a good reason why that should be so. Why should it be that consciousness is restricted to things made out of neurons? But there's also many other levels of substrate independence. There are things like, well, maybe it doesn't matter quite what the
molecules are, whether they're carbon or silicon, but maybe the structure of the mechanism still matters. So theories like integrated information theory pick out this middle ground. For integrated information theory, the substrate doesn't matter in the sense that silicon is just as good as carbon, but the mechanism does matter. You can't have a feed-forward neural network without any recurrency. Be conscious. It doesn't. On that theory, that's ruled out.
because it's a property of the mechanism. So there are many different ways in which things other than input-output mappings might turn out to be relevant. And the assumption that none of these things matter, I think, is a dangerous and weak assumption. And of course, that's the assumption on which these things like mind-uploading are based, that the idea that
It really doesn't matter that if I get the input output relations right, if the system is functionally identical, then I'm going to be conscious in my iPhone. I just don't think that's a safe way to think. Speaking of Tononi
I understand how psi can be measured in, let's say, toy examples in trivial, somewhat trivial, idealized states. I think you mean phi, by the way. Psi is very... Psi is his measure. Psi is like some sort of, you know, hokey stuff. OK, that's great. Although there may be a relationship, who knows, right? OK, so let's talk about phi. Is there a measure of phi that you have found in living humans? So phi in... Do you have to be living?
Yeah, they have to have dynamics. Is there a way of using neuroimaging to determine the phi of someone, let's say? The straight answer is yes, but it's not the same phi that Giulio would want to measure in his theory. There are approximations which I think he can measure. So phi mathematically is this measure of
How much information the whole of a system has about its evolution over time than the parts do considered independently. It's sort of a measure of emergence in this sense. You can also think of it a bit more loosely as a measure of combination of integration and information. The system is going to have high FI if it can enter more different states that make a difference for itself.
So, the information has to be for the system itself and not for an external observer. So, it has to be integrated in that way. Now, for duotenoni, to really measure phi, there's a problem in that to quantify the amount of information a system is generating by being in a particular state,
Technically, you need to know all the possible states the system could have been in, even if it's never been in any of those states. In practice, this is nearly always impossible to know. And it's impossible because we don't have a high enough resolution or for some other reason? Well, for some other reason. I mean, even if you could measure everything in precise detail, there are only certain systems, I think there are gothic systems where I forget my physics terminology now, but most systems will not
Unless you push them in some way, they may not explore all the possible states they could be in. They only explore a subset of their state space. And so you've got to push a system in all possible ways to figure out what all possible states it could be in are. And you can't do that just by having high resolution brain imaging. What you can do, let's assume you've got this fancy new technology you can
measure with arbitrarily high spatial and temporal resolution, you can measure now an approximation to find. There's still massive difficulties, computational difficulties in considering how you cut all these, what the right granularity of time and spaces that gives a maximum value of it and how you cut the system up to find what partition makes the biggest difference between the whole and the parts. There are massive problems.
But you can do it. And with my colleagues here, with Adam Barrett in particular, and Pedro Mediano in London, we've been developing for nearly 10 years now, some approximations to find that capture some of the spirit of it, that it's a measure of combined integration information, but which you can practically apply to brain imaging data. So that's certainly possible, but it has to be recognized that they are
approximations. As of now, they don't work very well when we apply them to actual data in the sense that they're pretty insensitive to, or rather they're very noisy. You can change subtle things in a system and then the measure changes quite a lot.
So I wouldn't have very much confidence applying these measures to empirical data, although it's certainly something we're still working on. I was reading a paper by Peter Lush a few months ago before I had researched you at all. Turns out you're a co-author on it, so that's pretty cool. It was about the rubber hand illusion.
and imaginative suggestion, demand characteristics, and phenomenological control. I don't recall it precisely and I wasn't sure about the relationship between the three. As far as I understand demand characteristics serve as an implicit imaginative suggestion and
As far as I understand, phenomenological control is the degree to which you can act on that suggestion, or the degree to which you can act on your expectation. Is this something like that? Do you mind just, if you know what you're talking about, outline it for the audience because I found it extremely interesting.
Yeah, this is a switching of gears again, but I'm glad you brought it up. There's a lot of terminology there. In one sense, they're all vaguely unsuccessful attempts to avoid saying hypnosis, because hypnosis has all this unfortunate historical baggage. I think there was the word hypnotizability in the paper. It'll be in there. But you have these, so let's take them one by one. So demand characteristics is a phenomenon that psychologists have known about forever, since the 60s, at least. It was formalized then, but I'm sure people knew about it before.
This is the idea that if you're doing a psychological experiment, oftentimes your subjects might implicitly or even explicitly know what you're trying to, what the right answer is, so to speak, and either just deliberately tell you what you were expecting to hear because they don't want to disappoint the experimenter or unconsciously actually have that sort of experience. If you, if you expect,
If the context of an experiment is strongly leading you to have a particular kind of experience in one condition rather than another, then you may well have that experience. And so in psychology, it's always been important to rule out demand characteristics if you want to say that something else is responsible, which basically means trying to say that people don't have different expectations for different experimental conditions.
And then if you still see a difference, then you can say, well, it's not because of their implicit expectations about what should happen. And then we get to suggestibility, imaginative suggestibility, hypnotic suggestibility. These are this speaks to there's a there's quite reliable individual differences.
in how hypnotically suggestible people are. And by suggestible here, I mean something like you can be asked to experience something like a fly crawling up your arm or something like that. And you might have, you might actually start to experience that. Um, you know, your hands are being drawn together. There are ways in which people vary in the extent to which a suggestion from a, from a third person can induce an experience.
That's what we mean by hypnotizability here. So it's not the kind of Darren Brown big magic stage magic thing. Well, that's fascinating too. It's more like just how much can your experience be influenced by what I say? And people vary a lot in this. You're in the YouTube, so Darren Brown is a huge celebrity, right? He's brilliant. Actually, he's a
So now you can start to see that if you've got an experiment where there might be demand characteristics going on such that the setup of the experiment leads you to expect some sort of experience in one condition but not another,
If you're highly hypnotizable, highly suggestible, the demand characteristics might have a stronger effect. I see. Because they basically act as a suggestion. And if you're more susceptible to suggestions, they're going to have a stronger effect. Now, the third piece is this term phenomenological control, which Peter Lush and Zoltan Dienas, my other colleague at Sussex, they sort of introduced this term basically to try and
Emphasize firstly that these suggestions can affect your experience hence phenomenological phenomenology and The idea of control is that it's the subjects you yourself. I you know, I give you the suggestion but then you're Controlling you're generating your experience conscious even though you're not aware of doing it. Yeah, that that's the point so I Can induce you to experience something if you're highly suggestible or
You're generating yourself, but you're not aware that you're doing it. It sounds like the placebo is related to the placebo effect. It's very related, right? Again, people who respond to the placebo effect, arguably, and there's some evidence that they're more highly hypnotizable. They're more suggestible. They're changing their experience in response to a suggestion. So there's this very big, typically uncontrolled variable in a lot of experiments of hypnotizability.
traits, phenomenological control, suggestibility, take your pick. And this matters if your experiment involves demand characteristics, because now the results you're going to get will depend on who you test. And so we've thought this is work led by Peter and Zoltan and Warwick, who I mentioned earlier, Warwick Roseboom, who's worked on the time perception stuff too.
So this is what's going on in the rubber hand illusion. Rubber hand illusion is a very famous thing. I mentioned it. I demonstrate it in my TED talk. And I tell the old story. So this is something where I've had to change my mind about it a little bit. You tell the old story.
Yeah, the pre phenomenological control. This is why I wrote down, because I remember you referencing the rubber hand illusion plenty. And I thought, okay, are you using this as a basis for your model? And I know that there's some holes that are poked in the rubber hand theory, at least by Peter lush. So I was like, oh, hey, that sounds interesting. But then I found out, wait, you co author that paper. So you should know about this. Am I correct in my interpretation of it? No, I mean, we're in fact, we're
We should change our minds, right? I mean, if I didn't change my mind about something, I wouldn't be a good scientist, right? So, so yeah, this is work. So that talk was from 2017. And this work in rubber hand illusion started maybe in 2018 or 2019. So but actually, they both fit with this general story. So this rubber hand illusion is this idea that my experience of I can I can change my experience of body ownership of what is my body in some fairly simple lab based way. If
If I put a rubber hand in front of you and your real hand is hidden from view and I stroke the rubber hand simultaneously with the real hand. So you're seeing stroking on the hand. You're looking at her hands. It's a rubber hand, but you're seeing stroke and you're feeling it too. Cause I'm stroking a real hand. Then for some people you start to have this weird experience that this hand is somehow part of your body, even though you know it's not. Um, and so simple story explanation for that.
is that it's just multi-basian multi-sensory integration that the brain sees touch and it feels touch and it's putting these things together and decides that's my hand. But there's this other factor which is that's a situation which is going to very strongly induce
demand characteristics. You're seeing something looks like a hand and you're being stroked and then the experimenter asks you, does that feel like your hand? You can see it's going to set up that expectation. And so what Peter's work beautifully did was to show that in fact, individual differences in imaginative suggestion and suggestibility correlate with how strong the rubber hand illusion is. I see.
And he also showed that typically people use as a control, they stroke the rubber hand out of time with a real hand. Yeah. So now this is going to break this multi-sensory integration because now you feel touch, but it's no longer aligned with the touch that you're seeing. And what happens? Well, people experience it much less. Yeah. But the point is people also expect to experience it much less. If you ask just people, what would they expect to experience when it's out of time?
They say, well, I wouldn't expect to experience it then. So it's not a good control for demand characteristics because what you expect to experience differs in both cases. I thought that what you did was great with the pulsing of the heart because I don't imagine that someone would think or would even be conscious of how their heart is pulsing to be able to associate the one that is in line with. Okay.
Does that not show that it's not purely the demand characteristics or the imaginative suggestion because you don't know you don't have access to how your heart is here that sound.
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Go to Shopify.com slash theories now to grow your business no matter what stage you're in Shopify.com slash theories. You do right away, but you're not paying. So I think I think unfortunately not in two different ways. One way is that in fact, uh, suggestion effects can influence basic physiology as well. It's not just limited to what you might subjectively report about your experience. You can induce physiological response
And the other thing is, you know, get that experiment again. So I was really and still am. I think it's a great experiment that we did at the time. But we did not look for individual differences in people suggestibility. This was like before we did this new work. So we did it a small family. The problem is this makes experiments in this area really hard because to
Peter's experiment where we measured hypnotizability and then looked at the rubber hand illusion. We did the experiment, or he did the experiment, well, a bunch of people did on, I forget, was it 430 or 340? Hundreds of people. Normally these experiments are done on groups of like 20 or something like that. And so
I don't know. In this experiment that you're referring to, where what we did was instead of stroking the hand, we gave people a virtual hand and it flashed either in time or out of time with their heartbeat. And again, we found that people experienced it more as their own hand when the flashing was in time with their heartbeat. So sort of what we called a cardiovascular, cardiovascular something, version of the rubber hand illusion, intraceptive version.
I don't know to what extent that's driven by suggestibility. I just don't know because we didn't measure it. And so we need to do it again. And we haven't yet. I'm also wondering, and I'm just thinking out loud here, if there is any utility to test this experiment when the participants are on psychedelics,
Yeah, so we've done some work in collaboration now with the group at Imperial College London led by Robin Cart Harris on what happens in the brain during psychedelics.
And there are lots of interesting differences. One of the challenges is that when someone's on a large dose of psychedelics, they can't really do anything. They can lie in a brain scanner, but you can't get them to do an experiment and press buttons and report what's going on.
One of the things I'm excited about is the potential for actually research in using microdosing here. So if you give people very small doses, sure, they don't have the big vivid hallucinations. Any differences in the brain are going to be correspondingly more subtle. But you have the big advantage that people can still do experiments. So I'd certainly like to
I think that's a very rich vein of work to follow. By the way, just to connect those two points, there was a lovely paper, I think, by Olson and colleagues from last year, where they claimed to have induced a psychedelic experience through hypnotic suggestion. It's called tripping on nothing. And they sort of set up the whole context, have a very nice relaxing lobby area and
People come in fully believing they're going to be taking part in some experiment with psilocybin and then they don't get any, but they're still led to believe that they have got it and then they often report all these hallucinations and things going on. So potentially you can even induce psychedelic effects given strong enough expectations about what's going on. Now, of course, I would say there's probably still going to be a difference between
What insights have you found from any of your psychedelic experiences, if you can talk about it, that you feel like were, let's say, worldview shattering or worldview forming? If anything, it was more reassuring because the thing is,
A lot of my work over the years has been about trying to understand perception as this kind of construction, this perceptual best guess. We've been talking about examples of seeing faces in clouds and all these effects that fit very comfortably with this view of how the brain works and how it does perception. So you think when you're on psychedelics, you're temporarily shifting with the Bayesian priors? Yeah, I think so. I think it sort of makes sense that way. Firstly, it gives you very, very
media insight that your perceptual world is a construction of some sort, you know, it starts departing from what it used to be quite, quite quickly. And it's interesting, people can have very different, I think, take different lessons from experiences like this, depending on their prior beliefs about them again. So if people believe that there's some sort of, some people might believe that psychedelics are evidence for a more immaterial
Because you suddenly depart from yourself, you don't experience yourself so much and so you might think, well, this is good evidence that consciousness is not this thing created by my brain somewhere behind my eyes. But for me, you also might reinforce beliefs and things like panpsychism, that consciousness is everywhere because the whole world seems to be alive and
vivid with meaning. But the other way to think of it is that if you come, say, somebody like me with a prior belief that the brain is the organ of experience, it's just more evidence for that because you mess with the brain in a very straightforward way. You just activate these serotonin receptors and bang, your experience of the world and the self massively changes. So I sort of interpret it as very strong evidence for the material basis of our conscious lives.
What do you make of Daniel Dennett's claims of, well, let's say Daniel Dennett's view of consciousness. Have you read his Explaining Consciousness book? I always find it insightful to know how, let's say, luminaries like yourself and others disagree. Well, Dennett is the luminary in this group. I started reading his stuff again at a reasonably early stage. So in the early 90s, I was lucky to read it, Consciousness Explained. And it's a remarkable book.
And, you know, I have been a lot inspired by Danit over the years. And I agree, I think, to a large extent, but maybe not the whole way. But that might partly be because I found it quite difficult to know what the whole way actually means for Danit.
Meaning you're unsure of what his viewpoints are? Well, I mean, I've had many conversations with him and I know there's a lot of... So one thing that I very much like about his ideas is this sort of idea about multiple drafts and center of narrative gravity and this sort of idea that
the self, the narrative self, this identity that we have, the thoughts that we think that it's not some sort of internal essence of self. There's just many things going on and we kind of construct our experience of being a continuous self. He's also, for me anyway, bang on about some of the mistakes that people make when they think about perceptual experience. So for instance,
He's, he's, he's very much. Actually, I will tell you, I'll tell you one story because he was at the, when I gave my TED talk in 2017, he was in the audience. And I was massively terrified giving this talk. It's a terrifying experience. Oh, you looked calm on stage. Yeah, it's a totally terrifying experience. But I was most terrified of the fact that then it was in the audience and wonder what he was going to think of it.
And he was very kind and he said it was almost perfect. And okay, what's the, what's the problem? He said, well, you said, like a father figure. He said, it's not good enough. No, he was, it was, it was, well, he picked out precisely the mistake. He wasn't to know about the rubber hand illusion stuff, right? That wasn't mistaken. Nobody knew about that. We hadn't done the work.
I'd said as part of the talk this idea of conscious perception as like an inner movie. And I can't remember the precise words I use now. I used to know them totally by heart. But this idea that I describe this multimodal, fully immersive inner movie as a description of what perceptual experience is like. And that's what he said.
he doesn't like that because it implies there's a little person in your head viewing it exactly exactly it implies even though i didn't mean it and i don't believe it just that linguistic slip it sort of it gives that impression it's easy to interpret that way and it might speak that i still fully hadn't grasped that point if you speak of an inner movie you imply
somebody watching the movie. No, there is no in the movie. Right, and that just begs the question. But I do recall, I do recall Dennis saying that it's okay to have a little person inside your brain watching the movie as long as that little person is another one. And it doesn't regress infinitely, because each little person can be different than the last. Do you remember this? Do you know this argument? Not, not really. I just think it's easier to do away with that argument at all. Yeah, there's no need for it. It's a it's a solution for that there's no problem that that
It's a solution to a problem that doesn't exist. Why would you need an inner homunculus anyway? Yes, we do have what we can call metacognitive processes. So I can make judgments about my conscious experiences. I can tell you whether I'm confident or not, or I can tell you whether I can reflect on and evaluate things that happen. But that doesn't mean there's a sort of inner observer. It just means there are hierarchical
organize that there's a hierarchical organization of my cognitive architecture um so yeah so he's certainly he's always i've always found him very on point about picking up on errors like that where i've never been entirely clear is these claims about
the extent to which we're mistaken about what it is we're trying to explain when we try to explain consciousness. He's often criticized or understood as saying that qualia don't exist. I'm not sure that that's what he means. I think it's entirely right to say that qualia, the redness of red, the painfulness of pain, are not what we think they are.
But that doesn't necessarily mean they don't exist. But yeah, I mean, for me, he's definitely one of the people I still always learn from every time I speak to. And it's been an interesting talking to him and seeing how he's talking more also in terms of the brain these days and trying to put his ideas
within that framework, which I think is a really interesting project. And do you agree with his conception of free will, the compatibilist approach? I'm a compatibilist. Yeah. I mean, I think free will is another kind of perceptual experience. And I think this whole debate about determinism is totally irrelevant to the understanding of free will. I'm trying to get it.
Dennis on the podcast, he said that he's busy writing a book, so he can't come on. I'm also trying to get Douglas Hofstadter. What are your views on Douglas Hofstadter's model of consciousness? I don't know him personally, and I've read only really the amazing Gertrude Bloch. It's one of the best books. Everybody should read that. It's phenomenal. It's just playful. What I take from that is just this credible
Playfulness, creativity. I have it right here. I keep only three books beside me or four books. It's one of them. Yeah, that's one of them. I don't know if you know this show, the Desert Island Discs. We have it on the radio here in the UK. And the idea has been going on for like decades. And the idea is you... What are the eight songs that you would take with you if you were getting banished to a desert island never to return? You can only take eight tracks.
And then you're also allowed, so most people in England spend half their lives figuring out what these eight tracks are going to be just in case they get invited onto the show at some point and you want to be ready. But you're also allowed to take a book. Cool. And so for you, that would be definitely, well, I wouldn't say it would be the one, but it would certainly be up there. I haven't made a decision about the book yet. But it's, so I love the way it just create, it playfully explores our intuitions about what cognition is, what mind is, what
Explanations in biology physics consistent. I think it's I think it's synopsis. He's a genius sort of insights. Yeah, have you read his analogy book? I Haven't I haven't it's a great one. It's a but it's a far too long. Sometimes it goes through lists and lists What I find it to be somewhat tedious. Okay. So what are your views on his views of consciousness? Where do you agree disagree? I
Well, it's a tricky question, because to be honest, I would be hard pressed to articulate what they are. I mean, to me, he talks about strange loops and things like that.
This is a real good story about Bronx and his dad Ryan, real United Airlines customers. We were returning home and one of the flight attendants asked Bronx if he wanted to see the flight deck and meet Kath and Andrew. I got to sit in the driver's seat. I grew up in an aviation family and seeing Bronx kind of reminded me of myself when I was that age. That's Andrew, a real United pilot. These small interactions can shape a kid's future. It felt like I was the captain. Allowing my son to see the flight deck will stick with us forever. That's how good leads the way.
Yeah, I don't have a particular strong view because to me I've always just associated him with these things about language, recursion, all these playful insights. So I don't think he's, as far as I know, has not come into my radar specifically about consciousness, more about what's self-consistent and what we think of as the self. When you were saying that the homunculus, it's a foolish model in some ways,
What about global workspace theory? As far as I understand, I don't know much about it. I just had a cursory glance at it. It sounds like there's a homunculus because there's something that's viewing or there's a... Well, you can explain it much better than I, but what are your views on the global workspace theory? So the global workspace theory is one of the sort of most popular theories in consciousness science, neuroscientific theories these days. It's first developed by Bernie Baas and
taken on mainly by Stander Haim in Paris, a neuroscientist. And it makes a very simple sort of proposal that what we are conscious of, the contents of our consciousness, they become conscious in virtue of being broadcast in this workspace in the brain that gives them access to many different cognitive processes, which is why I'm conscious of this glass of water means
I can do many things now in virtue of being conscious of it. I can drink it. I can tip it over the computer. I can take it to the kitchen. I can put it down again, drink from it. I can talk about it. And so that whatever in my brain is representing the perception of that glass has access to all these different flexible cognitive processes. And the global workspace theory, it's that process of
being available, broadcasted around this workspace that endows that perception with the property of being conscious. The analogy, I think it's done it again, uses the analogy fame in the brain for that.
Fame in the brain? Fame in the brain. So something becomes famous within the brain. All other parts of the brain know about it. Suddenly, my auditory cortex knows about it. My language centers know about it. My motor cortex knows about it. It's famous. There's a cup. There's a glass of water. Hooray! Everybody can see it. It's famous. And that fame in the brain underwrites conscious perception. So that's the claim.
The nice thing about it is it explains a lot of functional properties we associate with consciousness because indeed there are things I can do when I'm conscious of something that I can't when I'm not. And this flexible action is central to that. It's also testable because you can put people in brain scanners and change, present them with stimuli and vary whether they're consciously perceived or not. And you can look for
Is there this ignition of this global workspace in the brain when they're conscious? And many experiments would say there is. The issue with it is that it's not for me explaining a great deal about, and as we sort of begin to wrap up, we're back where we started, which is with phenomenology. So the fact that something is famous in the global workspace explains a lot about what we can do behaviorally and functionally
But it doesn't really explain to me, at least, well, why is this visual experience the way it is? The phenomenology of this visual experience has a character. Just being famous in the global workspace doesn't really explain that. It also is not going to address the hard problem of consciousness. Yeah, that's what I'm thinking. No one would claim that it is. But there's this often inverse relationship. It has a benefit of being eminently testable.
And although, you know, you can finess and say, well, the global workspace is wherever you find it in the brain. And there are problems because how do I separate the signature of a workspace being active from simply my consciously reporting something has happened? Maybe the difference I'm seeing in the brain is just the difference in my verbal report rather than in the mechanisms that give rise to the experience. So there are some tough questions there too, but it's
It's an appealing theory. I don't focus on it because for me I want to focus on what kinds of mechanisms explain phenomenology and for me the Bayesian perspective is much more interesting. Faraz, why don't you ask a question to wrap up and then I'll ask my last question as well. First of all, it has been a fascinating talk. Thank you so much for this conversation. Thank you, it's been great.
Yes. I thought it was going to be half an hour. It's certainly not half an hour. I'm sure our audience... Our perception of time has changed. Yes, it has. Just to wrap things up, maybe very briefly, if you could just let us know, maybe... Do you consider yourself as someone who looks at the world through a pragmatic lens as opposed to, let's say, maybe an objectivist lens? Because, you know, I always look at the world
I think there are different frameworks from which we can choose to look at the world. And to me, the pragmatic approach seems to be the one that matches really nicely with the evolutionary perspective. So I'm just wondering what your thoughts are on this. Very briefly, I know it's been a long time. Do you mean as a scientist or as a sort of person going about my daily life here? Do you think there's a
I suppose both would be interesting. As a scientist, it makes sense that you might want to take a more objectivist approach, but maybe as a person could be uninteresting. Well, I think there's always a blend, right? I mean, even as a scientist, there's a sort of objectivity is an ideal, right? You don't get there and much philosophy of science emphasizes how in practice pragmatic it is. You've got to do experiments. You come up with testable hypotheses and you don't have a kind of complete
It's not a hypothesis test ruled out either. It's sort of what ideas are more... Lakatos talks about experimental fecundity, what frameworks give rise to experimental predictions. And so, yeah, I think scientifically I'm quite pragmatic as well. I want to focus on areas of the problem where progress is conceivable.
Which is why I don't focus on coming up with a trying to think up some Eureka solution to the heart problem consciousness. I don't see if I can get there by doing stuff that can be done. And yeah, I guess that's the answer to say the other question part of your is that part of the reason why you dislike the heart problem just because of ostensible intractability? I don't dislike it at all. And you know, I think I think it just it crystallizes in a very, very
important way, an intuition about consciousness and a metaphysical challenge for explanations. It's just that I don't think addressing it head on is the most pragmatic, productive path for consciousness science to follow. Okay, so I have quite a few questions. I'm going to list them and then you could just choose one. Whichever one feels like it would give you the most bang for the buck.
I was curious you mentioned Grainger causality and I and you said that it wasn't used often in neuroscience And I want to know why is that the case then okay another question was the relationship between consciousness and intelligence not the way that Intelligence is used when people say artificial intelligence, but more like IQ the neuroscientific IQ And I was curious if there's been any tests where you give someone anesthesia How much anesthesia is required is proportional to the IQ of the person so that is one way of testing?
Is someone who has a higher intelligence more conscious in some sense? Okay, so I was going to ask you, okay, the one I wanted to know about your opinion on Bach's theories, Yoshabach. There's a slide in your presentation, I believe it was about the free energy principle and how it relates to... Hold on, you just picked the one you want me to answer. Okay, let's get back to artificial intelligence because you have a PhD in it. There's different architectures, some of the famous ones like GAN, convolutional,
Now, Yoshibok said that one of the ways that the GAN, that the Generative Adversarial Network, relates to the brain is in dreams. He thinks that dreams are like your brain testing you at your weakest point, almost like the adversary tests. Okay, so you get the idea. Now I'm curious. There's GANs, there's Convolutional Recurrent LSTMs, there's Transformer, and Boltzmann, let's say. That's right.
Are these different architectures, do you see them as related to different modules in the brain? Much like Yocha said, hey, well, the GaN might be somewhat related to dreams. Is it like the convolutionals is how we, it's a visual perception and it's pretty much that. Transformer is your ability to generate dialogue. Okay, can we pick a different question? Okay. I'm kidding. I'm kidding. Let's go with that. We'll have that one. We'll take it a little wider. Why is that a difficult question to answer?
It's kind of difficult. I mean, so yeah, my PhD in AI was quite some time ago, but we're actually still working on it. In fact, working on it more and more these days, again, with some super smart colleagues and grad students. And I think for the reason you just mentioned, because we have this, I think, so it's easy to say,
that the brain is making predictions about the causes of sensory data and that's what we perceive and it's doing some sort of Bayesian inference. So, but exactly how it's doing it and exactly how you can collect evidence to test these ideas of exactly what's going on depends on having much more sophisticated computational model of this process. So,
Which is why I'm very interested in these different classes of network. What can they explain about perception and behavior? How well do they map on to what we know, what we can measure in the brain? And actually the other way around, can we actually develop better machine learning architectures through understanding more about how the brain does these sorts of things? And there's good example. One of the things we're working on there is, for instance,
Most convolutional neural networks which are extremely good at classification require bucket loads of data. One of the reasons they started to work is that they can be trained on the internet. There's huge amounts of data and compute computation power and lots of interesting little tweaks but the principles of deep networks were there long before their renaissance. But we learn things
quite quickly. We don't need exposure to everything in order to learn new concepts and things like that. So we're doing it slightly differently. One of the things that humans and animals do when they learn is they select what data to learn from. You pay attention to different things. You forage for data. And so this opens a possibility. Can we define, can we design more efficient machine learning algorithms that gain efficiency
through selecting the data that they learn from. And then how do they know what data to look for? Well, that's a problem we can investigate in terms of what humans do. Is that related to the frame problem? No, not particularly. It's more, I mean, that's really a problem about how things come to have meaning or a simple grounding frame. Well, yeah, I guess that's sort of related. In the sense that this is really a much more much more kind of
Yeah, they're related in the sense that basically how much do you need to know about context and things to learn stuff. But just very pragmatically, what's the size of data set that you need in order to achieve certain performance and generalization capacity in a network? So that's one way. But the other way I think is more interesting from a perspective of what we've been talking about, which is do any of these classes of architecture in AI
Do they serve as useful ways to understand what the brain is actually doing, how it might be actually implementing or approximating something like Bayesian inference? And we'll finish just with a sort of simple line of thinking here, which is the still currently off the shelf networks that people are still excited about are basically feed forward networks.
These deep convolutional neural networks like AlexNet, CatNet, they're feedforward. There are many layers and they're trained on a lot of data, but they process it in this kind of feedforward direction. Seems the brain doesn't work like that at all. In fact, the whole frameworks that we've been discussing are more about top-down predictions being reined in by sensory data. They put a lot of emphasis on the recurrent top-down, inside-out connectivity.
And so to model that kind of activity, a feed-forward deep convolutional neural net is not sufficient. So we need to look at architectures that have top-down connectivity, that have generative models. And there are architectures like this? There are architectures. There are. And there are generative networks now. I mean, there's a long history of generative networks. They go back to the variational autoencoders and things like that. Helmholtz machines. Helmholtz being the same guy that is historically associated with
predictive perception and the Bayesian brain. But they became a little bit less less worked on because deep networks became so powerful so quickly. But now there's a lot of movement back towards the power of of unsupervised learning of generative models in networks, generative adversarial networks of one example of that, where one network will try and produce examples to fool another network's classification
You said that Yoshua talks about that as a good model for dreams. Indeed, it might be. There are many other ways to think about what dreams might be doing is just sort of pruning the complexity of a generative model. You let it free run and then you kind of prune its parameter space down a bit. And so there are lots of, I think, lots of interesting things to be explained about perception, cognition and consciousness through coming up with the right kind of
of machine learning architecture, computational model, and things that involve explicitly generative components that for me that's where the action is at the moment. Professor, thank you so much. I'm definitely going to be following your work and many of the people who are listening are going to follow your work from now. Where can people find out more about you? What are you working on next? Well, thank you. Firstly, thank you, Kurt. That was a very stimulating conversation. We could
Go on for longer, but I'm about to die, so I don't think we can. But thank you for a wonderful conversation. Thank you. If people are not already completely sick of stuff that I have to say, then you can find out more. Easiest thing is on my web page, which is www.annilseth.com. I'll leave a link in the description. And I think, as you mentioned at the top, there's, you know, there's a 17 minute version of all this is the TED talk, which is out there.
and I am putting the finishing touches to a book aimed at the informed general audience, so hopefully the kind of people that would be watching this, listening to this. The book is called Being You, a New Science of Consciousness and it's all being well will be out sometime between May and September next year. We haven't got a precise publication date but it's
The plan is to publish it in the middle of 2021, so in less than a year. And you can sign up on my website for updates about that book, if that's something you're interested in. Okay, everyone, go to his website, sign up, get notified when he comes out with this book. Follow him on, do you have Twitter? I do. Oh, yeah. Yeah, that's so you can follow me on Twitter. You will put the link in, but it's just at annual case. But yeah, you can follow me on Twitter too.
Thank you again. By the way, how is it that you stay so fit? Do you have a regimen? Do you meditate? Do you fast? Um, I didn't know why, why you think I'm, I'm that well, no, I mean, actually this, you look healthy. One of the, for me, one of the weird things about the pandemic this year, um, is I've not been, well, none of us have been traveling, but actually,
I've been lucky enough not to not to come down with it so far. And slightly paradoxically, I feel fitter than I have normally done because I've been able to keep a better routine. Just don't have jet lag all the time. And I can build going for a run two or three times a week properly into the routine. So actually doing looking after myself has become a little bit easier in some ways.
I find that academics and people who are more interested in intellectual domains tend to do well during this lockdown because they like to sit and write and not be disturbed. Well, if only it was like that. I mean, the flip side of that is, I mean, this has been a lovely conversation on Zoom, but the number of hours I spent on Zoom, time zones also seem to mean less because I can now just get wrapped into a meeting in California and the
Right. Night in Australia the next morning. It's like 7 p.m. there right now, or 8 p.m.? It's just coming up. And lastly, you went like this when you said that you don't have COVID. Do you feel strange as someone who, at least I would imagine, you think of yourself as a rational person? And this obviously doesn't do anything. But it feels right and it feels like if you don't do this, something bad may happen. So how does that comport with how you see yourself?
That's a really interesting question to finish. Yeah, I mean, it's still true. We still have these... I mean, partly it's a social signal, right? I just wanted to do that to... To indicate to the audience. ...to avoid having to say that, fortunately, so far, I have been able to avoid. It's kind of just a gestural shortcut. But still, academic understanding does not trump our lived experience all the time.
I still see colors as really existing in the world, even though I know they are constructions of the brain. So the way we, the way the study of consciousness changes me as a person is that everything changes, but everything stays the same too. It's great. It's a great talk. Thank you so much. Thank you. I look forward to reading your book, professor. Yes, I'm going to do it hopefully on vacation.
Get some rest, man. Thank you.
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"text": " This is Martian Beast Mode Lynch. Prize pick is making sports season even more fun. On prize picks, whether you're a football fan, a basketball fan, you'll always feel good to be ranked. Right now, new users get $50 instantly in lineups when you play your first $5. The app is simple to use. Pick two or more players. Pick more or less on their stat projections. Anything from touchdown to threes. And if you're right, you can win big. Mix and match players from"
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"text": " Now that's success. As sweet as a solved equation. Join me in trading that silence for success with Shopify. It's like some unify field theory of business. Whether you're a bedroom inventor or a global game changer, Shopify smooths your path. From a garage-based hobby to a bustling e-store, Shopify navigates all sales channels for you. With Shopify powering 10% of all US e-commerce and fueling your ventures in over"
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"text": " There's a lot of questions. This looks like some sort of super hard interview for some things. I hope you don't expect me to have answers for all of them. I'm here with Professor Anil Seth of neuroscience at the University of Sussex. There aren't many people who are brave enough to tackle consciousness scientifically. Maybe there's 1,000 people and there's"
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"text": " Maybe 5% of that are paragons in the field. So that's like 50 people, I'd say. And I would include Anil Seth in that. I'm super excited to speak with him. If you look up his talk on Ted, I believe it's one of the most viewed, we hallucinate realities. You might want to view that before watching this to get a, an overview of Seth point of views. I'm also here with Faraz who has a background in neuroscience and medical science and masters in it, actually medical science. And I thought it'd be great to have Faraz tag along."
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"text": " This is going to be somewhat free flowing because me and Faraz aren't communicating with each other off screen in some way. So at points he might interject that it might overlap with mine, but that's fine. We'll just take it as it goes. Welcome. Thank you, Professor. Thank you, Kurt. And Faraz, it's a pleasure to be here. So Professor, what are you currently working on and how did you get interested in the field of consciousness? So, well, two different things. I mean,"
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"text": " do something more normal with with life. So I've just been lucky enough to never have been forced to go out of these these questions. But of course that doesn't mean that every day is like 12 hours a day just trying to answer this big spooky mystery about consciousness. In fact day to day working in this area, working in this part of science translates into a whole variety of different things that are"
},
{
"end_time": 352.619,
"index": 14,
"start_time": 329.053,
"text": " related more or less directly to this big question. So just for example today we've been talking with my people from my research group and colleagues about various things like how do we mathematically get a grip on an emergent property? People often talk about consciousness as being emergent from the brain somehow but what does that mean mathematically? That's one thing. Another thing we were looking at"
},
{
"end_time": 382.551,
"index": 15,
"start_time": 353.097,
"text": " developing computer simulations of different kinds of hallucinations to get a better grip on how different kinds of visual hallucinations differ and what the underlying mechanisms in the brain might be. And then just before this meeting, I was with a PhD student at the very early stages trying to develop new kinds of experiments to understand the difference between what we might call gist perception, know that if you just"
},
{
"end_time": 411.732,
"index": 16,
"start_time": 383.234,
"text": " see a scene very quickly you can usually tell that it's a landscape or it's some very very basic features of perception come out very quickly but others require a bit longer to figure out oh am i looking at this person or that person or is it a car or what's what are the details going on so i'm very interested in thinking about how to explain these differences in visual perception so just to say there's just an awful lot of different"
},
{
"end_time": 435.794,
"index": 17,
"start_time": 412.415,
"text": " different specific questions that we can ask when we're trying to understand more about consciousness. Is it cool if we get some definitions out of the way? Yeah, I think that's always a good place to start. Right. Phenomenology, the way that you use it, I assume it's different than the philosophical doctrine of phenomenology, which is Husserl's, Heidegger's, and then there's particle phenomenology."
},
{
"end_time": 465.282,
"index": 18,
"start_time": 436.715,
"text": " and I'm unclear when you say phenomenology. Exactly. What do you mean? Well, I mean, I must admit I play a little fast and loose with with the definitions. And it's but the way I mean it is probably quite close to the philosophical phenomenology of Husserl and Meadow Ponti and people like that. Really, it's just for me a way of drawing attention to the properties of experience. So if we talk about, let's say, visual perception,"
},
{
"end_time": 494.565,
"index": 19,
"start_time": 466.049,
"text": " So perception here is how my brain interprets visual sensory data to form representations of the world outside. And you can think of that as having like a functional aspect. So what does perceiving things visually allow me to do? How do I behave with respect to visual information? But there's also a phenomenological aspect. There's how visual experience is seen, the experience of redness,"
},
{
"end_time": 522.244,
"index": 20,
"start_time": 495.35,
"text": " is different from the experience of, let's say, an object in vision. An object seems to have a back, even though I can't see the back. There's a phenomenology of objecthood. There's a phenomenology of spatiality. All my visual experiences have a spatial character, things organized in space in a way that, let's say, smell doesn't have so much. Emotions have a very different kind of phenomenology."
},
{
"end_time": 552.5,
"index": 21,
"start_time": 522.858,
"text": " And emotion feels different from any kind of visual experience. So I use phenomenology just as a way of thinking about what a science of consciousness should explain. What I think a science of consciousness should explain are phenomenological properties. Properties of experience. Why redness is the way it is in our experience and is different from an emotion or is different from a smell or a memory. That's what I mean by phenomenology. And when you say explain,"
},
{
"end_time": 576.51,
"index": 22,
"start_time": 553.2,
"text": " Part of the problem with consciousness are at least people who are less scientifically minded, who are disinclined to believe that consciousness can be studied materialistically. I think part of the issue is what it means to explain consciousness, what it means to explain any phenomena. So when you say we're trying to get an account of consciousness, do you just mean correlates? It's a very good question. I think there's a lot of"
},
{
"end_time": 599.138,
"index": 23,
"start_time": 577.295,
"text": " Ambiguity and confusion about what explanation means. I mean, whole books have been written about what explanation means in science. There's a beautiful book by Karl Kraver called explanation in neuroscience, which is anything in neuroscience. What does it mean to have an explanation of it? The way I think about it is an explanation in consciousness science"
},
{
"end_time": 628.063,
"index": 24,
"start_time": 600.452,
"text": " does not have to solve the whole problem that we come up with this intuitive eureka moment about now I understand how the electrochemical pate inside my skull gives rise to the redness of red. That would be nice, but we can have explanations that are relevant without that kind of big ticket prize. So by explanation, I mean more than correlation, and that's key. So"
},
{
"end_time": 658.507,
"index": 25,
"start_time": 628.643,
"text": " It's already a relatively standard method in neuroscience to look at the brain and see what changes in the brain as different aspects of consciousness change. What happens in the brain when you fall asleep or when you go into general anesthesia or what happens in the brain when you consciously perceive a scene versus you still respond to it but you know you're not conscious of it. So this is a standard method which is looking for the neural correlates of consciousness."
},
{
"end_time": 688.302,
"index": 26,
"start_time": 659.48,
"text": " Just finding correlations is not sufficient for explanations. Correlations provide constraints on explanations, but they don't provide explanations themselves. To explain something, what you want to have is in some way the correlation is no longer arbitrary. You want to have a sense that, ah, yeah, I see why that correlation obtains because it explains something about the thing it correlates with."
},
{
"end_time": 717.039,
"index": 27,
"start_time": 688.882,
"text": " Which for me means that the right way to think about this in terms of the brain and consciousness is not going to be so much this part of the brain is correlated with consciousness and this part isn't. It's going to be at a sort of intermediate level. Consciousness correlates with this kind of process, these kinds of dynamics in the brain, because they have similar properties that the conscious experience has. So we need a more kind of thinnest"
},
{
"end_time": 742.108,
"index": 28,
"start_time": 717.449,
"text": " bridge between what's happening in the brain and what's happening in experience. And if I can come up with something in the brain that tells me, oh, that's why consciousness in this case is the way it is and not some other way, then that's an explanation. In science in general, we judge the success of science, the scientific field,"
},
{
"end_time": 771.391,
"index": 29,
"start_time": 742.568,
"text": " Usually if it can explain something, if it can predict when things are going to happen and if you can control those things. Explanation, prediction and control are good criteria for the success of science. And I think we should apply those same criteria in this case too. This doesn't mean that it has to be intuitive. Quantum physics is extremely counterintuitive, but in terms of explaining phenomena, predicting and controlling, it's extremely good."
},
{
"end_time": 792.381,
"index": 30,
"start_time": 772.005,
"text": " So this leaves open that we might come up with a good theory of consciousness. And it might do the job of explanation, prediction and control, but we might never get the feeling that like, oh yeah, that's right. Now it all makes sense. This might not happen. Don't know yet. Let's take quantum mechanics as an example. The way that I"
},
{
"end_time": 818.422,
"index": 31,
"start_time": 792.944,
"text": " view it as it's more instrumental people who are studying quantum physics they're hesitant to say that it's an explanation they're more apt to say it's a model and it provides some predictions and it's an operationalist approach some people might take a more philosophical bend and say you know this is an explanation but truly truly i don't it's difficult to be a scientist and not be an instrumentalist and if you're an instrumentalist you're not"
},
{
"end_time": 844.36,
"index": 32,
"start_time": 819.582,
"text": " It depends on what you mean by explain. Is the fact that you can write equations that predict a certain number and then you find it in the data, does that mean that you've explained it? Well, I don't know. I don't know if that matches what people consider to be an explanation. But explanation is a tricky word to define. OK, now how's this related to the real problem? You mentioned that there's a hard problem, there's the easy problem, and then there's the real problem. That's your ante."
},
{
"end_time": 873.951,
"index": 33,
"start_time": 844.77,
"text": " So I'm curious, is what you just described the real problem and how does that delineate from the heart problem? Yeah, that's basically it. So again, this is a little bit fast and loose with these terms that are used in philosophy. So the heart problem has been one of the classic go-to's in people thinking about consciousness from a philosophical or neuroscientific perspective. It's due primarily to David Chalmers and the Australian philosopher. And he describes the heart problem of consciousness"
},
{
"end_time": 902.227,
"index": 34,
"start_time": 875.162,
"text": " It's this metaphysical problem, really. It's the idea that even if we had a complete description of how the brain as a mechanism worked, how it transforms sensory signals into actions, into our behavior, if we understood everything about the brain as a physical, chemical mechanism, there would still be a mystery about why and how any of that activity"
},
{
"end_time": 932.312,
"index": 35,
"start_time": 902.568,
"text": " should give rise to a conscious experience. Very broadly, why is consciousness part of our universe at all? How does it relate to the operation of physical stuff? That's the hard problem. And it is a very metaphysically loaded problem. It's really a question about the capabilities and limitations of physical explanations, explanations in terms of mechanisms."
},
{
"end_time": 953.968,
"index": 36,
"start_time": 933.217,
"text": " And it articulates the intuition that consciousness is somehow beyond the limits of physicalist and mechanistic explanation. Now, there's all this debate in philosophy and neuroscience about whether the hard problem exists, whether it's an illusion or whether it can in fact be solved."
},
{
"end_time": 983.234,
"index": 37,
"start_time": 955.452,
"text": " I put my cars on the table, we'll want to remain agnostic about that. I'm not sure whether the hard problem is a real problem that can or cannot be solved. But what I do think is that we can still ask questions about consciousness without sweeping it under the carpet entirely. So the easy problems are again, in Chandler's distinction, these are the problems that"
},
{
"end_time": 1012.363,
"index": 38,
"start_time": 983.677,
"text": " don't really appeal to consciousness at all. They're questions about how the brain works as a mechanism, how it can explain perception, sure, but any kind of perception, action, attention, behavior, language. But we can answer all the easy questions without referring to consciousness. Now, there's, I think, an enormously rich middle ground, which is to appreciate that conscious experiences exist. Let's assume that they do and"
},
{
"end_time": 1040.316,
"index": 39,
"start_time": 1013.012,
"text": " We have experiences of color, of shape, of emotion, all sorts of things. And we can start to try to explain the properties of these conscious experiences in terms of mechanisms. This is exactly what we were talking about. Can I explain why a visual experience is the way it is and is different from, let's say, an emotional experience in terms of brain mechanisms?"
},
{
"end_time": 1070.845,
"index": 40,
"start_time": 1040.998,
"text": " And if I can do that, I think I'm making progress on the scientific explanations of consciousness, even if I'm not going directly after the heart problem. Now, other people have expressed pretty similar ideas. Chalmers himself called the this approach something like the mapping problem, how to build non-arbitrary correlations between things in the brain and things in the world of our experience. Other people have talked about neurophenomenology. This goes back to Francisco Varela in particular."
},
{
"end_time": 1091.476,
"index": 41,
"start_time": 1071.578,
"text": " Just pretty much the same thing again, how do we link things happening in the brain to things happening in our experience? So there's a tradition of thinking this way. Do you see that the okay for us? Yeah, sorry, I just wanted to talk about the role of perception in all this because"
},
{
"end_time": 1115.026,
"index": 42,
"start_time": 1091.92,
"text": " I find the way you have described in the past the perception's relationship with reality quite fascinating. You have previously said before that, famously in a way, you have said that normal perception is controlled hallucinations. Now, this idea of hallucination or illusion, I suppose first of all, do you distinguish between these two words, hallucination and illusion, or can we use them interchangeably?"
},
{
"end_time": 1142.807,
"index": 43,
"start_time": 1115.725,
"text": " Maybe you can answer this and then I have a follow-up question to this. Sure. I mean, well, let me first say that I think it's a lovely phrase, perception is controlled hallucination. I certainly didn't come up with it. I heard it from one of my mentors, Chris Frith, who heard it somewhere else. And actually a few of us, we've tried to find out the proper origin of it. And I've never been able to. Sort of there's this legendary seminar, UCSD, sometime in 1990."
},
{
"end_time": 1170.896,
"index": 44,
"start_time": 1143.217,
"text": " which people refer to, but it was never recorded and it's just, so who knows? Anyway, the phrase does the rounds, but I think it's a good phrase and we'll get onto hallucinations in more detail, I'm sure, in a bit. I'm not sure I would use it interchangeably with illusion. Illusion, I think, is a very problematic word too, because illusion sort of implies that there is"
},
{
"end_time": 1201.698,
"index": 45,
"start_time": 1172.09,
"text": " In the context perception that there is a non illusory perception that there's such a thing one might call veridical perception, which is the sort of we're seeing the world as it really is. And when we're hallucinating or experiencing an illusion, then we're not seeing the world as it really is. But my view on this is we never see the world as it really is. Everything that we perceive is consciously experienced"
},
{
"end_time": 1228.729,
"index": 46,
"start_time": 1202.056,
"text": " in our perceptual work is a construction that's only indirectly related to what's actually there. It's just that the degree to which these perceptions are constrained by what's actually there differs. So I think illusion for me, and I'm thinking about this now really for the first time to how I would distinguish it. Illusion is probably a very systematic"
},
{
"end_time": 1255.674,
"index": 47,
"start_time": 1229.514,
"text": " relationship between what's there and what we perceive that is not necessarily maladaptive. It can often be just useful. It's sort of a quirk of the visual system where a normal way of constructing our perceptions is revealed to be quirky in some way. And then hallucination is something a little bit more unusual. Hallucination usually means that I'm having an experience that you're not."
},
{
"end_time": 1286.067,
"index": 48,
"start_time": 1257.039,
"text": " or that other people aren't. And it is no longer adaptive in that same way, no longer necessarily so useful. But I wouldn't say it's a hard and fast distinction. If you look at, for instance, if we look at fluffy clouds and see faces in clouds, then this is probably something many of us do. And you could equally call that an illusion or a hallucination. And strictly the word for that is the Greek term pareidolia, seeing patterns in things."
},
{
"end_time": 1311.305,
"index": 49,
"start_time": 1287.159,
"text": " So I think there's interesting sort of landscape of these terms. Right. And then to follow up to this idea, I mean, the general population might think that, for example, illusions are in a way negative limitations that might prevent us from reaching the supposedly noble goal of, for example, searching for the truth, let's say. Right. But, you know, you and others such as, let's say, Donald Hoffman, you've"
},
{
"end_time": 1340.964,
"index": 50,
"start_time": 1311.783,
"text": " brilliantly argued that illusions are actually could be in a way a gift for example in your talk about consciousness you bring up the Adelson's checkerboard illusion phenomenon and in a way my question with this would be that if we have pragmatically evolved in a way not to experience reality in its true form you know it's about fitness in a lot of ways from an evolutionary perspective and are better off if truth is in a way evolutionarily or perceptively"
},
{
"end_time": 1369.872,
"index": 51,
"start_time": 1341.442,
"text": " driven toward extinction, then why should we want to get to the root of reality as a whole? Isn't ignorance bliss in this specific case? There's a lot of loaded phrases there about truth. Of course, truth matters. And there are things that we can't perceive, which make a huge difference to us. If we could perceive coronavirus particles, I'm sure people would be much more willing to wear masks."
},
{
"end_time": 1390.179,
"index": 52,
"start_time": 1370.299,
"text": " And if you go and jump in front of a bus, whether or not you're looking at it, it's going to hurt. So I'm certainly not being anti-realist about this. There's a real world out there. We don't know quite what it is. Best ask a physicist for that, what the ultimate nature of reality is."
},
{
"end_time": 1417.654,
"index": 53,
"start_time": 1391.681,
"text": " But it's certainly true that whatever it is, is not, we don't have and can never have direct access to it, to perception. And this is a very old point. Immanuel Kant, I think, says it, Plato said it, but Kant especially talked about the Newman and that the sort of the external objective reality that's forever hidden behind a sensory veil. So in a sense, it's an elusive goal to think that we could ever perceive"
},
{
"end_time": 1446.613,
"index": 54,
"start_time": 1418.302,
"text": " the true world in the sense of having direct perceptual access to physical reality. But what we perceive is constrained by that reality. That's what perception is all about. It's a way of constructing a world for us that is usefully constrained by whatever's really out there. And as you said, and Don Hoffman has said, a whole bunch of people have said this really, that as soon as you appreciate that"
},
{
"end_time": 1477.159,
"index": 55,
"start_time": 1447.159,
"text": " Our perceptual experience is not a direct reflection of an external objective reality. Then it's quite easy to think that, well, what we perceive is going to be tuned by evolution to what best keeps us alive. And I think there's a really deep truth to that. And you can think about it in one of the very simple examples like color. We experience colors as usually we experience them as really existing properties of objects in the world."
},
{
"end_time": 1503.814,
"index": 56,
"start_time": 1477.773,
"text": " color seems to be a property of an external objective reality, but we know that it isn't. And we don't even need neuroscience for that. Newton has shown that color is not a thing in the physical universe. There's this whole continuous spectrum, any part of it that we were able to, that can shape our experience at all. We create this universe of colors from"
},
{
"end_time": 1534.394,
"index": 57,
"start_time": 1505.077,
"text": " The fact that our eyes are responsive to roughly three different wavelengths, but we see way more than three colors, which for me is fascinating because in one sense we are perceiving much less than what's actually out there because we don't experience X-rays or infrared or ultraviolet at all. But in another sense, we're experiencing much more than what's out there because we create a universe of colors just from combinations of three wavelengths and the brain does this."
},
{
"end_time": 1560.316,
"index": 58,
"start_time": 1534.735,
"text": " because colors are very useful to guide our interaction with the world. They're a way for the brain, in this case, to keep track of surfaces when lighting conditions change and to distinguish between different kinds of surfaces. It's a very, very useful thing for the brain to figure out what to do. So I don't think of it as, in this case, it's not like we should"
},
{
"end_time": 1589.684,
"index": 59,
"start_time": 1560.759,
"text": " The goal should be to not experience colors anymore and experience just those three wavelengths of light. I mean, no, even though that's closer to objective reality in some way, that seems like an odd goal to have. I think that the interesting thing is just to understand much more about this relation. How do we construct the universe of color from a very limited sampling of physical reality? And why is that a useful thing for the organism to do?"
},
{
"end_time": 1615.503,
"index": 60,
"start_time": 1591.015,
"text": " I mean, one example that comes to my mind regarding this was the idea that, for example, you have an organism that might be tuned to fitness in terms of understanding small and large quantities of some resource as, let's say, one color, let's say red, and anything that is in the middle as another color. So for that specific organism, it doesn't really matter whether"
},
{
"end_time": 1645.725,
"index": 61,
"start_time": 1615.964,
"text": " that resource is in a large or small quantity. That's why it sees it as the same color. And what matters is whether it's in the exact amount that the organism needs. So in a way, evolutionarily, the organism evolves to not distinguish between small and large amounts of a quantity. And that leads to evolution in a way hiding the truth that is behind it. So that idea just"
},
{
"end_time": 1676.203,
"index": 62,
"start_time": 1646.323,
"text": " Yeah, I think there's something right about that. I know various people, Don Hoffman as well, uses this idea of the metaphor of the desktop, right? The desktop on your computer is useful because it hides all the stuff going on in the operating system that is not useful for the user of the computer to see. We just want to drag a file into a folder and be unaware of what's actually happening to make that happen. And so indeed, I think there's every reason to think that perceptual systems"
},
{
"end_time": 1703.302,
"index": 63,
"start_time": 1676.971,
"text": " Let's take this Hoffmanian argument a little further. So the argument is that there's no relationship between or there's little relationship between truth and fitness and we're tuned for fitness given that we're not seeing reality or at least we can't claim to. Now, given that, how can we ever make any claim that there is an objective world or what the characteristics of this objective world is like? Now,"
},
{
"end_time": 1730.23,
"index": 64,
"start_time": 1703.951,
"text": " You made a claim in one of your talks about misperceiving yourself, that some mental disorders can be seen as you have the wrong idea about yourself. How can you have a wrong idea that to me implies objective, but it's difficult to know the objective without making reference to adaptiveness? Okay, so I think, I don't think anybody's saying there's no relationship between truth and fitness or perception. It's just not, they're not the same thing."
},
{
"end_time": 1759.855,
"index": 65,
"start_time": 1730.981,
"text": " So, but there's going to be some overlap. Like if my, if my perceptual system reliably represents things as far away when they're close and I try and cross the road, I'm going to get run over. And that's, that's, and so that's, that's not a good way for perceptual system to be organized. So that there is a, there is a systematic constraint between what's out there and what I perceive."
},
{
"end_time": 1777.432,
"index": 66,
"start_time": 1761.271,
"text": " Yeah, I'm not sure if that's true. Now, let me just rub my butt, because there are ways that you can form graphs. There's something called quantum graphs. I believe it's used in loop quantum gravity. But regardless, where you can represent what's far as close and what's close as far,"
},
{
"end_time": 1802.722,
"index": 67,
"start_time": 1777.875,
"text": " And this actually Hoffman does make this argument that there is virtually no relationship between truth and fitness. One of the ways he does it, I have my objections and anyone who's listening can watch the podcast. One of the ways that he does this is by saying, let's imagine that the universe at the objective world has some property of structure. Let's say it's a group structure. Let's say it's a partially ordered set, whatever it may be. Then let's imagine the totality of the ways that you can perceive."
},
{
"end_time": 1832.5,
"index": 68,
"start_time": 1803.353,
"text": " You find that as the complexity of the system increases, the amount that conforms with reality, now in this example I gave is a group or a partially ordered set, but there are various other structures, that the amount of ways that you conform with reality divided by the total amount of ways you can experience it goes to zero. So he may argue, now he's not here, and I could also be misrepresenting him, but he may argue that there is virtually zero relationship between what's out there and how we perceive it."
},
{
"end_time": 1861.834,
"index": 69,
"start_time": 1832.995,
"text": " And in fact, okay, sorry, please. I mean, again, we probably would need him to see exactly where he's planting his flag. And but but I think I still suspect a slight confusion here because I would I would also I'm also of the view that and we've said this earlier that I can never perceive what is actually that that the nature of"
},
{
"end_time": 1890.316,
"index": 70,
"start_time": 1862.278,
"text": " the physical universe, assuming there is one, which is still up for grabs, right? That is something that is not directly accessible, can never be directly. Perceptual mechanisms just don't get there. That's not what they can do. So in that sense, there will always be a gap between our perception and what is there. However,"
},
{
"end_time": 1920.179,
"index": 71,
"start_time": 1892.244,
"text": " precisely because our perceptual mechanisms have been shaped by evolution they will have been shaped so as to be adaptively constrained by the regularities in the physical universe that are important for our survival which is precisely why if i'm crossing the road i will see things as far away when they are far away and as close by when they're close by i mean the other the other thing"
},
{
"end_time": 1949.855,
"index": 72,
"start_time": 1920.418,
"text": " A useful distinction here I think goes back again philosophy to Locke and the British empiricists who distinguished between primary and secondary qualities. And a primary quality for Locke is something that exists independently of a mind or of an observer. So something like having solidity and moving are properties that exist independently of a mind or an observer, which is why"
},
{
"end_time": 1978.012,
"index": 73,
"start_time": 1950.35,
"text": " If I stand in front of an onrushing bus, it's not going to go well. But then there are other properties like color, which are for lock secondary qualities because color requires the interaction between an observer or a mind and the physical universe. Suzanne also talked about this. He said color is the place where the brain and the universe meet. And so there's"
},
{
"end_time": 2002.739,
"index": 74,
"start_time": 1979.343,
"text": " at least two ways of thinking about the kinds of things that are, two ways of a way of partitioning our ontology. And they're both, but in neither case is our experience identical to whatever its hidden causes are in the world."
},
{
"end_time": 2032.312,
"index": 75,
"start_time": 2004.241,
"text": " Whether it's a primary quality or a secondary quality, we're always constructing on the basis of those qualities or properties, we're constructing our experience. It's just that for a primary property, for a primary thing like solidity, it's going to exist whether we are conscious of it or not. But our perceptual mechanism will still be constrained by it. We will, a well-designed perceptual system"
},
{
"end_time": 2059.172,
"index": 76,
"start_time": 2033.285,
"text": " will be constrained in ways that makes us behave appropriately to these things. Right. I don't want to remain stuck on this, but I guess my objection is the notion of farness and nearness is dependent on space and space time itself. This is something Donald Hoffman likes to reference. There's a physicist named Nima Armani."
},
{
"end_time": 2084.65,
"index": 77,
"start_time": 2059.633,
"text": " Hamed, I believe, but many physicists, almost every single physicist, believes that space-time is not fundamental, which means that location... You may say that, well, we're constrained. Constrained is not the same as... And you're definitely admitting that there's not a one-to-one relationship between reality and then how we perceive it. But then even in these examples of solidity, well,"
},
{
"end_time": 2105.606,
"index": 78,
"start_time": 2085.299,
"text": " What's solid in quantum mechanics where the wave function spreads to the universe? Sure. But there's something. OK. But firstly, I think actually you bring up a very interesting point. We're getting very deep into the weeds here. But for me, one of the most interesting things about this way of thinking about perception is how far you can take it."
},
{
"end_time": 2134.957,
"index": 79,
"start_time": 2105.896,
"text": " and so for instance yeah i can i can perceive a color as and i can understand the perception of a colored surface in terms of an invariance in how a surface reflects light and under different lighting conditions and so on but then what about what you might call the deeper structure of perceptual experience we mentioned this right at the beginning as well the fact that visual experience is spatial that we overall tend to"
},
{
"end_time": 2163.302,
"index": 80,
"start_time": 2135.247,
"text": " experience the world in this three plus one dimensional way, in three spatial dimensions and one time dimension. Can we understand that as constructed in the same way that we would understand the experience of color as being constructed? Is our brain generating this architecture of experience through the same principles? Because yeah, from a more"
},
{
"end_time": 2193.456,
"index": 81,
"start_time": 2163.78,
"text": " physics-based perspective, you might say, well, actually, this three plus one dimensional picture is not the most accurate picture of the physical universe. And we could argue, and I would not have an expert view about what is, but I know there are many options out there. Even relativity tells you that the three plus one distinction is not as solid as our perceptual world would lead us to imagine. And then, of course, you've got string theory and also Bok universes and all sorts of stuff."
},
{
"end_time": 2221.63,
"index": 82,
"start_time": 2194.292,
"text": " But in a sense, you can be agnostic about what that ultimate reality is, if there is such a thing, and still ask the question of, OK, so what's constructing? How do we experience time and space, not just objects within time and space? And I think, for me, that's a really exciting direction to push this kind of research. Speaking of the perception of time, I remember you said, this is obviously known, that the more adrenaline you have in your system"
},
{
"end_time": 2248.302,
"index": 83,
"start_time": 2221.834,
"text": " Let's say it peaks, you feel like time has slowed down. Well, I wasn't sure I said that. I mean, certainly there's just this kind of popular assumption about time slowing down under various sorts of high arousal situations. And actually time here is something that I've been working on just for the last four years or so. And it's really due to one of my colleagues, Warwick Roseboom, an Australian"
},
{
"end_time": 2275.469,
"index": 84,
"start_time": 2248.422,
"text": " cognitive scientists to join join the group in 2015 and brought a deep interest in a wealth of expertise on time perception. So he's been leading our work there. And one of the so one of the I think, really fascinating lines of argument that he's making, and I agree with him, it seems right is that is to push back against this idea that we"
},
{
"end_time": 2305.725,
"index": 85,
"start_time": 2276.015,
"text": " experience time in virtue of having a little clock inside the head. A lot of work in this area boils down to an assumption like that, that there's time unfolds in the world. And certainly, when we're making judgments about time, we often get it wrong. If we measure an objective duration, and then we ask people how long that duration was,"
},
{
"end_time": 2335.879,
"index": 86,
"start_time": 2306.152,
"text": " People can be wrong about it. And they're systematically wrong in the same way they're systematically wrong about many other things in perception. And for instance, there's a very general law in perceptual psychophysics where people are biased towards the mean of the things they're judging perceptually. If you see a whole load of circles of different size,"
},
{
"end_time": 2364.138,
"index": 87,
"start_time": 2336.425,
"text": " and then you're asked to judge the size of the next circle. You'll be biased towards the mean of the circles that you've already seen. It's called regression to the mean. And in time perception, you do exactly the same. If you experience a load of different durations, let's say just beeps of different lengths, and you're judging the duration of each beep, you'll be biased towards the mean. And this is a very useful signature that"
},
{
"end_time": 2377.227,
"index": 88,
"start_time": 2365.657,
"text": " There's something like Bayesian inference going on here, that your perceptual judgment about a situation is based not only on the sensory data, but on your prior expectations."
},
{
"end_time": 2406.305,
"index": 89,
"start_time": 2377.824,
"text": " about what's going on. Bayesian inference is simply this way of combining what you already know with what new information you have to come up with a best guess. When you say that we're biased toward the mean, do you mean that of what we experience first? So it's like we take a sample of our first experience and take the mean of that and then our later experiences are then biased toward that mean? Or do you mean we're biased toward the totality of the experiences means? Well, this is a good empirical question, right? It might depend. So"
},
{
"end_time": 2436.937,
"index": 90,
"start_time": 2407.5,
"text": " It probably depends on the details of the experiment over what time scale the brain is taking the mean and it's going to vary by task, by context and so on. In this case, I was really talking about fairly short time scales where you can show that you're just on the last one or two minutes of what's going on, then you'll be biased in your next decision."
},
{
"end_time": 2467.073,
"index": 91,
"start_time": 2437.142,
"text": " towards basically the mean of that. But then you could make the argument, although it's much harder to demonstrate empirically, that for instance maybe my experience of duration in general is biased by the mean of every experience that I've had and my ancestors have had and so on. But of course I can't manipulate that in the lab. So in the lab I can only manipulate context over relatively short time scales and see what the effect is. But this is a very circuitous route to this idea of"
},
{
"end_time": 2493.763,
"index": 92,
"start_time": 2467.875,
"text": " of time slowing down and so firstly for me there's a very interesting distinction here between perception of duration and the experience of the flow of time that's interesting so there's a difference between those two yeah i think that is it's"
},
{
"end_time": 2523.473,
"index": 93,
"start_time": 2494.036,
"text": " We can perceive something as lasting a certain duration, but the experience of just how fast time is going is different. It's different in this, again, in perception in general, we can separate the change of perception from the perception of change. So, I can experience my perceptions having changed, but then the experience of the change is itself a kind of perception."
},
{
"end_time": 2547.483,
"index": 94,
"start_time": 2524.616,
"text": " There are various phenomena, things like change blindness, which show this very nicely that if something, if I'm watching just like an image, which I'm assuming is not changing, but actually maybe the background color changes very slowly, you'll find that people won't notice that change. And sometimes people say there's a paradox here because"
},
{
"end_time": 2574.804,
"index": 95,
"start_time": 2548.507,
"text": " They didn't notice that change, but they're now looking at a different thing. So how does that work? And I think that the resolution is to say, well, no, that perception has changed, but they didn't perceive the change because change of perception is not the same as perception of change. So I think the similar thing plays out in time as well. That perception of duration is not the same thing as the perceiving time flowing. And it's much harder to to get an empirical handle on"
},
{
"end_time": 2604.804,
"index": 96,
"start_time": 2575.691,
"text": " The Flow of Time, my favorite experiment here. I don't know if you've come across this by a guy called David Eagleman and Chet Stetson, I think, was his researcher at the time. And so they had this idea that if indeed my perception of time is slowing down at moments of high arousal, so let's go back to that. How can I test that? Well, so they sort of thought, well, if time is"
},
{
"end_time": 2611.903,
"index": 97,
"start_time": 2605.213,
"text": " Slowing down then maybe if I do have some sort of internal hear that sound"
},
{
"end_time": 2639.019,
"index": 98,
"start_time": 2612.875,
"text": " That's the sweet sound of success with Shopify. Shopify is the all-encompassing commerce platform that's with you from the first flicker of an idea to the moment you realize you're running a global enterprise. Whether it's handcrafted jewelry or high-tech gadgets, Shopify supports you at every point of sale, both online and in person. They streamline the process with the internet's best converting checkout, making it 36% more effective than other leading platforms."
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"text": " There's also something called Shopify Magic, your AI powered assistant that's like an all-star team member working tirelessly behind the scenes. What I find fascinating about Shopify is how it scales with your ambition. No matter how big you want to grow, Shopify gives you everything you need to take control and take your business to the next level. Join the ranks of businesses in 175 countries that have made Shopify the backbone of their commerce. Shopify, by the way,"
},
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"text": " powers 10% of all e-commerce in the United States, including huge names like Allbirds, Rothies, and Brooklynin. If you ever need help, their award-winning support is like having a mentor that's just a click away. Now, are you ready to start your own success story? Sign up for a $1 per month trial period at shopify.com slash theories, all lowercase. Go to shopify.com slash theories now to grow your business no matter what stage you're in."
},
{
"end_time": 2725.64,
"index": 101,
"start_time": 2696.596,
"text": " The clock that's the ticking of which is underwriting this perception then maybe there are more ticks of the clock going on in a particular objective duration so then I would experience time is dilated and so that was the reasoning and so to test it he had this beautiful experiment where he gave people watches that were specially designed so they would flash numbers"
},
{
"end_time": 2755.452,
"index": 102,
"start_time": 2726.305,
"text": " But so quickly that if you just looked at them now, you just see a blur. You wouldn't be able to decipher what the numbers or the letters were. And so he then had people bungee jump while looking at this watch several times, then go to the crane, look at the watch. And the hypothesis was, well, if subjective time is slowing down because an inner clock is increasing its rate,"
},
{
"end_time": 2785.469,
"index": 103,
"start_time": 2756.34,
"text": " This frame, right? Let's say, then maybe these people should be able to read what's being passed. What do you think happened? I would imagine they did. Right. No, they didn't. No, so it was a really interesting failed experiment. I mean, it wasn't failed because the evidence was pretty clear, but it ruled out that simple explanation that, yeah, this clock is speeding up. Because people subjectively still had experienced"
},
{
"end_time": 2815.589,
"index": 104,
"start_time": 2785.879,
"text": " So that's super interesting to me, because to me it sounds like what you're saying is we can be wrong about our own perceptions. For example, OK, or I'm posing this as a question. Can I say I see this cup as red? I see. Sorry, let's look at this. I see this as blue."
},
{
"end_time": 2845.674,
"index": 105,
"start_time": 2816.63,
"text": " I see this cup is blue. Could I be wrong about my own perceptions? I think I see it as blue, but is it possible? Like in the example of these people who say that time has slowed down, but they're wrong about that. Can I be wrong about seeing this as blue? Now, in fact, you know, with our shared reality, this you can may be able to objectively measure it as blue. Can I be wrong about my perceptions?"
},
{
"end_time": 2873.37,
"index": 106,
"start_time": 2847.637,
"text": " I think there's at least two very interesting responses to that. Philosophers often talk about the ineffability of conscious experiences, this idea that we can't be wrong. If I'm in sharp pain now, that's just a fact and I can't be wrong about it. When I think about claims like that, the first thing is"
},
{
"end_time": 2903.916,
"index": 107,
"start_time": 2874.275,
"text": " One problem is a sort of epistemological problem, like how would you know? When the claim is about a subjective experience, what's the right way to validate that against? So does it even make sense as a question being wrong about your own experience? But what might it mean? It might mean that you are wrong in your interpretation about it. And I think that's usually what people mean when they say that"
},
{
"end_time": 2932.824,
"index": 108,
"start_time": 2904.497,
"text": " They're wrong about their perception. They might say that, for instance, I experienced time is slowing down. But then if you actually look at how they estimated the duration of something, it may be basically the same as in another case. So they are"
},
{
"end_time": 2961.63,
"index": 109,
"start_time": 2934.411,
"text": " you write in the sense that they're giving a sort of face validity you know what they're experiencing but all the ways one might interpret that might might be wrong take another another very i think illustrative example um people for thousands of years have reported out of body experiences they'll have experiences where they're"
},
{
"end_time": 2990.657,
"index": 110,
"start_time": 2962.039,
"text": " floating above their physical body or floating around a roof or going out the window, whatever. Are they wrong about their experiences? Well, in one sense, no. If that's the experience they're having, and they're not just sort of confabulating it later on, then that's the experience they're having. But"
},
{
"end_time": 3014.309,
"index": 111,
"start_time": 2991.084,
"text": " If they interpret that experience as evidence that their self has in fact left their skull and gone flying around, then they're wrong. That's not the right way to interpret those kinds of experiences. Or rather, there are plenty of other options by which you might interpret those kinds of experiences. And you can also be wrong"
},
{
"end_time": 3042.739,
"index": 112,
"start_time": 3015.009,
"text": " just in the small space that opens up between the moment of your experience and the moment of your report. And if I tell you what I'm experiencing, I have to remember it, even if it's only for a very short time. And you could be misremembering. You can systematically misremember stuff. There are many ways where we can introduce"
},
{
"end_time": 3073.166,
"index": 113,
"start_time": 3043.677,
"text": " introduce indirectness between your experience and your report of that experience. So you can be wrong in that sense too, I think. But there is something for me that it almost doesn't make sense to ask the question, can I be wrong about my experience in the here and now, bracketing all these things about interpretation and report, because there's no criteria to judge it against apart from the experience itself. Yeah, for us,"
},
{
"end_time": 3101.971,
"index": 114,
"start_time": 3073.456,
"text": " If I may, because this is one of the questions I had in mind, which ties really nicely into this. You most likely know about Jill Bolte-Taylor's famous TED Talk, the stroke of insight, the one where she goes into detail about her experience of having a hemorrhagic stroke on the left side of her brain. And then she experiences these feelings of euphoria. She goes into the state of nirvana because the way she's describing it, she thinks her"
},
{
"end_time": 3131.049,
"index": 115,
"start_time": 3102.244,
"text": " the right side of her brain is sort of taking over. And then once her left brain comes back again, then suddenly she comes back to her version of the version of reality that we experience and she realizes, okay, something's wrong. I have to go get some help. And that talk generally was really fascinating to me, but I just wanted to know your thoughts on that kind of experience. And maybe we can follow up with the idea of, from a neuroscientific perspective, the left and right brain"
},
{
"end_time": 3160.316,
"index": 116,
"start_time": 3131.664,
"text": " I suppose my question is twofold. One is what are your thoughts on the way she was describing that out-of-body experience, in a way you could call it an out-of-body experience, and secondly, the distinction between left and right brain."
},
{
"end_time": 3188.831,
"index": 117,
"start_time": 3161.732,
"text": " Yeah, I don't have too much to say about the first one, about the sort of experience of bliss or nirvana. Again, people do report these kinds of experiences in various conditions. There are examples, what comes to my mind are these examples of so-called ecstatic seizures. So some people with epilepsy"
},
{
"end_time": 3219.326,
"index": 118,
"start_time": 3189.377,
"text": " experience reliably these moments of bliss and awe and presence of the numinous and all sorts of wonderful experiences, either in the penumbra or the periphery of their seizures or maybe even during the seizures, I'm not entirely sure, to the extent that sometimes they don't want to be medicated or they don't want to be relieved from their seizures because they get"
},
{
"end_time": 3247.807,
"index": 119,
"start_time": 3219.633,
"text": " this from them. Quite what's going on for these sorts of experiences is extremely hard to say, I think. And the part of the problem is, it's been extremely difficult to investigate them in controlled conditions in the lab where you can actually see, okay, this is what's going on. Is it a wash of a particular kind of neurochemical activity in this or that part of the brain? It's unclear. So some of the stuff from epilepsy shows that these"
},
{
"end_time": 3277.278,
"index": 120,
"start_time": 3248.37,
"text": " Some brain regions seem to be more implicated than others, but I wouldn't want to put too much stock in those. But it's a fascinating class of experience. Sure. And I think, again, there's a lot of, certainly a lot of interest and there has been a lot of activity for ages about the neuroscience of meditative experiences. It doesn't have quite the same end point, but certainly there are examples of people in"
},
{
"end_time": 3305.998,
"index": 121,
"start_time": 3277.619,
"text": " meditative states who will experience the dissolution of the self and the ego and so it's kind of fascinating to see back to where we started. So what in the brain can explain that kind of phenomenology, that kind of dissolution? An open question. The second thing about laterality in the brain left versus right hemisphere and this is"
},
{
"end_time": 3336.357,
"index": 122,
"start_time": 3306.732,
"text": " It's a huge, it's a, as other than most people will know, we hear these tropes and these cultural tropes about the left brain being analytical and the right brain being holistic and artistic and left brain. And as with all these things, there's a grain of truth underlying this, but it's only a grain. And pretty much for everything you do, the both hemispheres of the brain are working together. Some things are more lateralized than others."
},
{
"end_time": 3364.684,
"index": 123,
"start_time": 3336.783,
"text": " And so this is a few of these things, a couple of these things. When you get more towards output and input, things tend to get more lateralized. So if you have a stroke in one half of your visual cortex, that will affect one half of your visual field. If you have a stroke in your right hemisphere, your motor cortex will be paralysed on your left hand side. So these things are very lateralized. And that's not particularly mysterious."
},
{
"end_time": 3394.991,
"index": 124,
"start_time": 3364.991,
"text": " So most of the time, it's working together. I think the super interesting studies here, I don't really like very much this habit of"
},
{
"end_time": 3419.36,
"index": 125,
"start_time": 3395.469,
"text": " describing people as left-brained or right-brained. I think that's some kind of neophrenology stuff. But what's still really interesting are these old case series, these neurosurgical case series of people with what we call calisotomies. These are people who've had split brain operations. This used to be done"
},
{
"end_time": 3446.681,
"index": 126,
"start_time": 3419.855,
"text": " It's pretty rare now because other medications become more effective. But for people with really, really severe and intractable epilepsy, one of the options was to cut all the majority of the fibers connecting the two hemispheres, hence the term split brain. And there's some absolutely fascinating observations. This goes back to people like Mike Gesaniga and Joe Bogan, someone who would"
},
{
"end_time": 3477.398,
"index": 127,
"start_time": 3447.449,
"text": " This would give the two hemispheres different input to try and ask the question, are there two separate conscious subjects now, now that you've split the brain like this? And there are very suggestive hints that there's something weird going on. You can show, I always get my left right mixed up because so many things cross over here. It's very hard to keep straight about it. But if I show my, hold on, this has to be my,"
},
{
"end_time": 3502.637,
"index": 128,
"start_time": 3477.671,
"text": " Right visual. Right. Forget about the location. Anyway, if information gets into my right visual cortex that doesn't get into my left, then typically the person is not able to verbally say what that is because the left language side doesn't have access, but will maybe try to confabulate what's going on."
},
{
"end_time": 3529.275,
"index": 129,
"start_time": 3503.012,
"text": " So the right hand side might still be able to draw what they see. And then the left hand side will make up some story to justify why the right hand has drawn it. And so these are, these are really, really super suggestive, but it's still never been entirely clear. This basic question of are there two, have you, have you divided one person into two or not? Because a lot of the early studies,"
},
{
"end_time": 3557.363,
"index": 130,
"start_time": 3530.145,
"text": " turned out to have been methodologically limited in various ways. And so now with sort of more modern methods in the few patients that are still around, perception does seem to be more integrated across the visual field than we would have thought. But to me, it's still a fascinating case about could we divide a single conscious person into two conscious people? And what would it be like to be one or other half?"
},
{
"end_time": 3570.452,
"index": 131,
"start_time": 3558.848,
"text": " Yeah, so just to clarify one point then about it, the idea that, for example, the right brain, as she was describing in this way, where she sort of, when the right brain was coming into"
},
{
"end_time": 3599.224,
"index": 132,
"start_time": 3570.845,
"text": " into effect, she felt like she was connected to everything around her. She no longer felt like an individual. She felt like she was everything. And she describes it as the we sort of experience. And then when the left side comes back in, that's where the individual self comes back on. Now, this definitely sounds like a really interesting analogy, dichotomy, that sort of thing. But I just was wondering from a neuroscientific perspective how much truth"
},
{
"end_time": 3628.66,
"index": 133,
"start_time": 3599.787,
"text": " exists here and whether we have any evidence of this I versus we sort of distinction. Well, I think there's certainly there is a distinction between or rather the experience of being as an individual separate from others and from the world is something that varies and it varies for each of us at times. If you're fully immersed in something, you tend to experience yourself as"
},
{
"end_time": 3656.596,
"index": 134,
"start_time": 3629.394,
"text": " less separate from them. And people call this sometimes by the term flow experience. If you're in a crowd dancing or a football game, you feel part of the crowd. And that's not just a metaphor. It picks out, I think, a valid aspect of your experience of reduced individuality at that time. People on LSD, that's also one of the classic"
},
{
"end_time": 3684.718,
"index": 135,
"start_time": 3657.688,
"text": " reports from psychedelic experiences is a dissolution of the ego and a feeling of connectedness not now not just with other people but with the with nature with the world and So that you know all these things together suggest that well, there's a brain basis for the strength of our experience of individuality and"
},
{
"end_time": 3711.561,
"index": 136,
"start_time": 3684.957,
"text": " But I don't think it comes down to simply right brain versus left brain at all. I see. And just so that I can go back to one of your other statements that I found really interesting, you mentioned, please correct me if I'm wrong, you mentioned that an object would exist regardless of whether we perceive it or not. I believe that's what you said. I'm wondering how this ties to John Wheeler's ideas"
},
{
"end_time": 3733.882,
"index": 137,
"start_time": 3711.886,
"text": " regarding, for example, he makes an assertion in the sense that a conscious observer is a necessity in order for us to declare that something exists. Without the conscious observer, it's like part of a formula that without it, if we remove it, we cannot make any claims whatsoever about whether something exists or not."
},
{
"end_time": 3762.244,
"index": 138,
"start_time": 3734.36,
"text": " So how does the idea that you brought up tie into that? Do you agree or disagree with that? Well, you said two separate things, though, which were different. So one is what are the conditions for something to exist? And the other was what are the conditions for us making claims that something exists? And I think if it's the second, then observer is probably needed. You can't make an inference about an existence without an inferrer. But whether there are objects,"
},
{
"end_time": 3789.036,
"index": 139,
"start_time": 3762.637,
"text": " whether objecthood or intrinsically requires observer that that's again that's it I think that's a it's a deeply physical metaphysical question so John Wheeler who you mentioned is I mean I always associate him with this idea of of giving information some real status and ontological status and he's famous for the slogan it from bit that everything that we"
},
{
"end_time": 3820.111,
"index": 140,
"start_time": 3790.23,
"text": " measure, whether it's using the tools of science and physics or experience, fundamentally, our universe is written in the language of information. And then, you know, from that, then there's all sorts of ways of understanding that that kind of claim, because some sorts of informational relationships are fundamentally relative. Shannon information, we can think of that way. It's a sort of"
},
{
"end_time": 3851.903,
"index": 141,
"start_time": 3821.954,
"text": " depends on a sender and a receiver. Other ways of thinking don't, but to me that's now, that's a sort of, I'm not trying to dismiss the interest of these things. I think that they're fascinating and actually they do play into how we might read certain contemporary theories and consciousness science in particular, things like integrated information theory from Giulio Tononi. Then it makes a big difference what you think information is."
},
{
"end_time": 3878.558,
"index": 142,
"start_time": 3852.193,
"text": " What do you think it's, if you're with Wheeler or not? But for the most part, I don't think what I was saying about objects, you know, I want to bracket those discussions away from that. And it may be true that in some physics-based way that we can't say anything exists unless there's an observer, but"
},
{
"end_time": 3908.729,
"index": 143,
"start_time": 3881.681,
"text": " For the story I'm trying to tell, which is just this idea that what we perceive is always a construction, but underlying that construction, there are hidden causes that we can never directly have access to. I think that stands whatever you think about the ontological status of information. You're just looking at it at a different level in a way. These are distinct levels that"
},
{
"end_time": 3933.558,
"index": 144,
"start_time": 3909.445,
"text": " might make sense on one aspect, but not on the other. That makes sense. What are your views on the Sapier-Whorf hypothesis? Now it really does feel like an interview, like bang, bang, one hard question, another. Oh, and just, okay, you can gather your thoughts on that, just as an aside, because this bothers me. I'm not a theoretical physicist, but my background is in theoretical physics."
},
{
"end_time": 3963.746,
"index": 145,
"start_time": 3934.206,
"text": " When people make claims of consciousness being associated with the observer and quantum mechanics, much of that is over exaggerated and taken up by the new age community because they tend to like to use the word consciousness and tend to want it to have some ontological foundational status. And it might be, that might actually be the case, but it's over exaggerated and it's extremely contentious. And I believe something like 90% of physicists don't believe that to be the case. The way function can collapse when there's another electron or another set of electrons,"
},
{
"end_time": 3991.442,
"index": 146,
"start_time": 3964.94,
"text": " Objective quality like atoms observing another photon then you can collapse the photon and but even that's a bit That's a bit that has to be stated more technically because there's something called coherence and decoherence Either way take those claims that the conscious observer is necessary for the collapse of a wave function with a grain of salt Absolutely, I mean and you guys gonna know much more about physics I mean I started off in physics, but I"
},
{
"end_time": 4020.828,
"index": 147,
"start_time": 3991.749,
"text": " I switched to psychology when physics became too hard. I'm super interested in your background, man, because you also went back to do a computer science master's and an artificial intelligence PhD, if I'm correct. Yeah, that's right. Yeah. Okay. That's super cool. Well, we'll talk about that after. So let's talk about Sapir-Whorf. Okay, so Sapir-Whorf hypothesis is really is this idea that language either determines or shapes perception that"
},
{
"end_time": 4051.92,
"index": 148,
"start_time": 4023.012,
"text": " that the linguistic environment we live in influences the perceptual environment that we live in, I think is probably one way to say it. Technically, people will talk about cognitive penetrability here, that is the way we see the world or hear it or smell it. Is that invaded by higher level beliefs?"
},
{
"end_time": 4079.087,
"index": 149,
"start_time": 4052.637,
"text": " cognitive processes of which language is exemplary. So the Sapir-Wolf hypothesis is that, yes, that the language that we use shapes the way we perceive it. And this can be, you know, this can be in kind of sort of subtle ways, like, how do I perceive time? Is that dependent on the way I use"
},
{
"end_time": 4106.8,
"index": 150,
"start_time": 4079.514,
"text": " language. There are all sorts of lots of interesting anthropological experiments looking for languages where, for instance, in Western languages, we tend to think of the future as ahead of us and the past as behind us. But I think it's the Aymara. This is something I was very secondhand on. But there's reports of some indigenous South American cultures"
},
{
"end_time": 4132.295,
"index": 151,
"start_time": 4107.227,
"text": " For which it's the other way around. Language is for which the other way around. That the past is ahead of you and the future is behind you. The reason being kind of makes sense to me is that, well, you know, you can see the past. You know, I know what happened in the past. It's happened. So therefore it's within my line of sight. But the future is unknown. I don't know what's going to happen. So I can't see it. So it's behind me. So these... But would that linguistic difference"
},
{
"end_time": 4161.527,
"index": 152,
"start_time": 4132.534,
"text": " that sort of metaphorically shapes how we talk about time, but might it actually influence the way we perceive time? So there are all sorts of interesting questions about how deep these influences might go. To me, it's sort of a priority that I'd be surprised if the Sapir-Whorf hypothesis is not true. Right. That's my instinct. People seem to find it appealing, I think, is because of this"
},
{
"end_time": 4189.326,
"index": 153,
"start_time": 4161.886,
"text": " this idea that there's this modularity in the brain, that we have perception, which is some sort of encapsulated at some lower level, we form this perceptual representation of the world, and then we think about it, and we talk about it, and we make decisions about it, and then we go and we do stuff, we make a plan for what I'm going to do next, we do stuff, and then we perceive the world again. But the brain doesn't work like that, I don't think. And what you were describing was a bottom up approach?"
},
{
"end_time": 4216.493,
"index": 154,
"start_time": 4190.316,
"text": " Well, it's sort of more just an approach of extreme modularity. So people like Jerry Fodor is known for this view that one of the longest running arguments in neuroscience has always been about functional localization. To what extent of different things the brain does localize different brain regions. And the pendulum has swung back and forth on this. Obviously, both extremes of"
},
{
"end_time": 4245.606,
"index": 155,
"start_time": 4217.142,
"text": " can be ruled out to start with you can't have a brain where bits different bits do different things and don't talk to any other bits. And you can there would be no point to that because you'd have no cross communication anyway. Right, exactly. And you can almost equally rule out the other extreme, although you can't quite rule that conceptually, but certainly, empirically, it's ruled out very quickly, you have damaged different bits of the brain, different things go wrong. And"
},
{
"end_time": 4273.985,
"index": 156,
"start_time": 4246.834,
"text": " But you can still, but there's still a more subtle level, there's still this argument about the degree to which functions, let's say a function like language, is just served by a particular network or brain region. And so those bits of the brain do language. Yes, they talk to other bits of the brain, but they don't sort of bleed over into those other bits."
},
{
"end_time": 4302.619,
"index": 157,
"start_time": 4274.872,
"text": " Computers like this laptop computer is kind of modular in this way that you know, there's a chip that does memory a chip. That's the CPU Chip that's the IO ports and so on you can replace these somewhat interchangeably So it's pretty modular that so this kind of design is a reasonable way to design systems Many of our technology design this way that typically biological systems don't end up being designed this way and if we look at"
},
{
"end_time": 4331.015,
"index": 158,
"start_time": 4303.166,
"text": " Now that we know a bit more about how things like visual perception unfold in the brain, they're not limited to just the visual cortex. So the way I and many others think about perception is that it's this hierarchical set of predictions about the causes of sensory inputs. Many of these happen in visual cortex, but some of them happen outside of visual cortex. So"
},
{
"end_time": 4356.886,
"index": 159,
"start_time": 4331.527,
"text": " things like language will interact with visual cortex in interpreting, coming to the best guess of the causes of sensory inputs. And there's a lot of experiments now. There's a great paper by Gary Lupien. I think he's at University of Madison, Wisconsin. He sort of took this debate more into the realm of experiment and just"
},
{
"end_time": 4383.234,
"index": 160,
"start_time": 4357.79,
"text": " summarise a load of evidence showing that words influence perception in pretty clear ways. So this to me is not surprising, but it's also there's just there's lots of interesting questions about how far this goes. Again, this is always a question. How deep do these influences go? What kinds of things are are amenable or influenceable by things like language?"
},
{
"end_time": 4409.923,
"index": 161,
"start_time": 4383.848,
"text": " It seems like there's a controversy around it when you even just look at the Wikipedia article about the Sapir-Whorf hypothesis. Pinker and Chomsky are both against it being true, and I haven't had a chance to look up their arguments. I'm curious if you could explain to me, as well as the audience, what are Chomsky's, and to a lesser extent Pinker's, but I'm more interested in Chomsky's, arguments against it. Yeah, to be honest, it's not something I've studied much either. My feeling is that"
},
{
"end_time": 4440.06,
"index": 162,
"start_time": 4410.828,
"text": " I mean, Chomsky is known for his ideas about universal grammar. I mean, he's such an interesting character because he in many ways put the nail in the coffin of behaviorism. So saying that, okay, we need to take mental internal mental processes seriously. And we can't just infer them always just on the basis of behaviors. We need to we need to assume some complex internal mechanism. Of course, he was doing this in the in the domain of language. And"
},
{
"end_time": 4467.312,
"index": 163,
"start_time": 4440.333,
"text": " saying you can't explain linguistic behavior purely from a behaviorist perspective on what people say, just how quickly human beings learn language, there's just, he would say that there's not enough information in the stimuli that babies are exposed to for them to infer grammar. And people still will argue about that, you know, they'll say, well, actually, there is, and it just depends on because they're interacting with it. And so I'm not a linguist, I don't want to come down on"
},
{
"end_time": 4495.469,
"index": 164,
"start_time": 4467.654,
"text": " one side or other there. But Chomsky's view became this idea of this sort of language acquisition device, this very, very circumscribed system in the brain that was for language. And so I think if you take that perspective, you are, you're going to be disinclined to the Sapir-Wolf hypothesis, which is really motivated by an idea that there isn't this kind of modularity in the brain, that"
},
{
"end_time": 4503.08,
"index": 165,
"start_time": 4495.811,
"text": " There is to some extent, there's specialisation, but there's not a complete kind of encapsulation."
},
{
"end_time": 4530.776,
"index": 166,
"start_time": 4504.309,
"text": " A KFC tale in the pursuit of flavor. The holidays were tricky for the Colonel. He loved people, but he also loved peace and quiet. So he cooked up KFC's 499 chicken pot pie, warm, flaky with savory sauce and vegetables. It's a tender chicken filled excuse to get some time to yourself and step away from decking the halls. Whatever that means. The Colonel lived so we could chicken."
},
{
"end_time": 4555.879,
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"start_time": 4530.776,
"text": " When you brought up the idea of the visual cortex being related to other areas of the brain, what that reminded me of was the... I believe there was a study that they conducted with regards to color detection being tied to"
},
{
"end_time": 4584.411,
"index": 168,
"start_time": 4556.425,
"text": " If in the language that that individual spoke, there were actual words that would define a certain color, then that individual was capable of identifying that specific color. But if a language did not have that specific color, it hadn't been developed in that language and that person would not be able to detect it."
},
{
"end_time": 4613.814,
"index": 169,
"start_time": 4585.674,
"text": " I'm just wondering what... This is sort of a piece of evidence, right? That sort of connects. Yeah, that's a good... another piece of evidence sort of in favor of Sapir Orf, right? Exactly. And I think that the example that comes to mind when you talk about that, I think it's Russian, right? And I don't speak Russian, but I believe Russian has more words for blue than English. Maybe, maybe. And colors, you can test this really nicely with color because"
},
{
"end_time": 4643.268,
"index": 170,
"start_time": 4614.616,
"text": " Colors is a beautiful example of categorical perception. You have a continuous wavelength that we typically experience as a number of discrete colors with bits of blurry boundary. What happens when you look at a rainbow? I mean, that's what you see, even though the color is, the spectrum is continuously changing. So to assess categorical perception, you sort of ask, you present people with differences on this continuous scale and ask them to judge how far apart they are."
},
{
"end_time": 4672.432,
"index": 171,
"start_time": 4643.746,
"text": " Their judgment changes quite a lot at some times, but not other times, then you then you infer, oh, there's a category boundary there. And so, yeah, I think this is again, for me, it's a bit secondhand, but I'm prepared to accept that people who who learn Russian from birth, I don't know about if you learn it as a second language, may divide their experiences of blue into more categories than"
},
{
"end_time": 4698.456,
"index": 172,
"start_time": 4673.08,
"text": " People who have a different linguistic environment. Against me, it's like, okay, this is kind of fine. I don't... Well, for me, it shouldn't be a controversial perspective to adopt because I think this is how perception works in general. We also notice for things like, let's say, wine tasting. You... Initially, all wines, all red wines basically taste the same."
},
{
"end_time": 4728.78,
"index": 173,
"start_time": 4699.002,
"text": " And then as you learn, you sort of learn to distinguish them, but then you learn to apply different labels to different kinds of wines, and then those help scaffold your ability to distinguish them still further. The problem is you've got a sort of chicken and egg thing here. What comes first? Is it that you experience things differently and then label them? Or can it be the other way around? And with many of these things, I think it's probably not a good idea to seek an answer to that. It's a circular kind of causality that bootstraps these differences into existence."
},
{
"end_time": 4756.51,
"index": 174,
"start_time": 4730.026,
"text": " Do you mind repeating that last part? Why is it that you can't start with the concept and then be able to perceive that concept afterward? So for example, I don't know the difference between cyan and turquoise and magenta and purple and their cognates. Do you know? It just looks like blue and some blue and I know green and red and so on and I could take 10 seconds to look it up and then probably solve it for the rest of my life. But either way, I see that as bluish green. I see that as purple."
},
{
"end_time": 4785.469,
"index": 175,
"start_time": 4757.892,
"text": " Am I seeing the same as someone else, but just not noticing? And is that seeing and noticing? Yeah. Yeah. Okay. That's good. I mean, in that particular case, I don't know, we'd have to do experiments to know that, right? We'd have to, we, what we'd have to do is give these, these different colors to you and present them in sort of pairs. So you make judgments about how similar they are to each other. And then we'd have to see, are you making reliable distinctions?"
},
{
"end_time": 4814.787,
"index": 176,
"start_time": 4786.323,
"text": " between these colors that you linguistically describe as the same compared to somebody who has different words for these different colors. So I think these things all boil down to empirical questions. Now, here's one test. This might not be doable, but imagine you look at a scene and let's say it has some discriminable phenomenon that are indistinct at first because you don't have the language label for it."
},
{
"end_time": 4839.326,
"index": 177,
"start_time": 4815.026,
"text": " cyan and turquoise for me for example and you show that to me and I just oh that's bluish or this bluish green then a day later you teach me the phenomenon of cyan and turquoise and I'm able to to discern then you put me under hypnosis to remember to remember yesterday and you say was cyan on the left or the right in other words I'm wondering"
},
{
"end_time": 4868.541,
"index": 178,
"start_time": 4840.384,
"text": " because i don't notice it initially do i also not see it does it not get recorded or does it get recorded so that i can go back later now with my proper disambiguations and disambiguate okay that's interesting i mean i like the experiment design apart from hypnosis but i think there's whichever method choose whichever method allows you to get an accurate memory it's hypnosis is real but it's not what most people think it is it's not sort of um"
},
{
"end_time": 4899.309,
"index": 179,
"start_time": 4869.394,
"text": " It's not this kind of stage. I wave a watch in front of you and you can remember your child. Anyway, but I think there's so I can indeed imagine this experiment where you make a perceptual judgment. I then give you some prior some additional knowledge. You make a judgment again and then you try and you just try and remember what what you did the first time and can you be more accurate when you're retrospectively making a judgment"
},
{
"end_time": 4927.346,
"index": 180,
"start_time": 4900.418,
"text": " given now some additional knowledge than you were at the time. There's almost certainly stuff like that has been done. I don't have it to the tip of my tongue. But yeah, that's an interesting design that could certainly address the question of... Well, I don't know quite what question it would be addressing because the problem is there's many things being conflated here. There's sort of memory"
},
{
"end_time": 4954.104,
"index": 181,
"start_time": 4928.114,
"text": " along with perception at the time. There's all these things, it really depends on what the specific question is you're trying to ask. But I think it's pretty clear, there's lots of, you know, there are lots of experiments that show indeed that expectations, what you expect to happen, can directly influence perception. These expectations can be set up by linguistic phrases, so I think there's lots of good evidence that what we think, what we"
},
{
"end_time": 4978.985,
"index": 182,
"start_time": 4954.633,
"text": " What we say that the structure of our thoughts in our language can indeed influence how we see the world. Is there a limitation to the Bayesian model of the brain? I know that it can't explain everything because there's no model that explains everything. You'd have the Holy Grail right there. And I know that you are a large proponent of"
},
{
"end_time": 5006.817,
"index": 183,
"start_time": 4979.923,
"text": " the Bayesian model of how the brain works. I'm curious, where are its limitations? I'll give you one example from my life. I was playing a video game and someone in the, I was expecting the person, I was expecting the person in the video game to say the word extinction. And I was listening, I was watching and she said something and I thought it was, she said entity instead, but I was expecting extinction. So then I rewound it and she in fact did say extinction. So I thought that was strange because I expected extinction."
},
{
"end_time": 5037.483,
"index": 184,
"start_time": 5007.961,
"text": " She said extinction, but I heard entity. Now these are rare. But when they come up, I do write them down. Another one was I was looking for some object on my desk. Let's say it was a pen. I don't remember what it was. Let's say it was a pen. It was right here. And I didn't do a cursory glance. I looked for a second, not half a second, but a glance. And I didn't see it. And I was expecting to see it because I'm looking for it. And I looked back, and it was right where I initially looked. So there's some. OK, you understand."
},
{
"end_time": 5067.773,
"index": 185,
"start_time": 5037.807,
"text": " Let's just take a step back and say very briefly what the Bayesian model is. Bayes' theory is just this way of reasoning with probabilities. It's this idea of inference to the best explanation. In terms of neuroscience, the idea is that that's what the brain is basically doing all the time."
},
{
"end_time": 5097.534,
"index": 186,
"start_time": 5068.37,
"text": " perception is a best guess about the causes of sensory data. It's not a direct readout. There is sensory data. It's trying to combine prior expectations about the causes of sensory data with the sensory data to come up with the best guess. And all of these things are sort of probabilities. It provides a standard of"
},
{
"end_time": 5101.237,
"index": 187,
"start_time": 5097.739,
"text": " hear that sound?"
},
{
"end_time": 5128.37,
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"start_time": 5102.244,
"text": " That's the sweet sound of success with Shopify. Shopify is the all-encompassing commerce platform that's with you from the first flicker of an idea to the moment you realize you're running a global enterprise. Whether it's handcrafted jewelry or high-tech gadgets, Shopify supports you at every point of sale, both online and in person. They streamline the process with the internet's best converting checkout, making it 36% more effective than other leading platforms."
},
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"end_time": 5154.445,
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"text": " There's also something called Shopify Magic, your AI-powered assistant that's like an all-star team member working tirelessly behind the scenes. What I find fascinating about Shopify is how it scales with your ambition. No matter how big you want to grow, Shopify gives you everything you need to take control and take your business to the next level. Join the ranks of businesses in 175 countries that have made Shopify the backbone."
},
{
"end_time": 5177.79,
"index": 190,
"start_time": 5154.445,
"text": " of their commerce. Shopify, by the way, powers 10% of all e-commerce in the United States, including huge names like Allbirds, Rothy's, and Brooklynin. If you ever need help, their award-winning support is like having a mentor that's just a click away. Now, are you ready to start your own success story? Sign up for a $1 per month trial period at Shopify.com"
},
{
"end_time": 5207.585,
"index": 191,
"start_time": 5177.79,
"text": " The theorem in mathematics and probability theory is really telling you what the optimal way is to combine information under conditions of uncertainty. And so in one sense, it's not really"
},
{
"end_time": 5238.302,
"index": 192,
"start_time": 5209.07,
"text": " something that can be right or wrong. It's a standard of optimality. How use it to think, well, okay, that's what the brain, that's the problem the brain should be solving if we've got the cost function right. If we're assuming the brain is solving the problem we think it is, it tells you the optimal way to do it. That's one way to interpret it. Another way is more literal to say, no, this is actually what the brain is doing than the"
},
{
"end_time": 5252.312,
"index": 193,
"start_time": 5238.797,
"text": " That's a much stronger claim."
},
{
"end_time": 5272.466,
"index": 194,
"start_time": 5254.684,
"text": " Razor blades are like diving boards. The longer the board, the more the wobble, the more the wobble, the more nicks, cuts, scrapes. A bad shave isn't a blade problem, it's an extension problem. Henson is a family-owned aerospace parts manufacturer that's made parts for the International Space Station and the Mars Rover."
},
{
"end_time": 5300.947,
"index": 195,
"start_time": 5272.466,
"text": " Now they're bringing that precision engineering to your shaving experience. By using aerospace-grade CNC machines, Henson makes razors that extend less than the thickness of a human hair. The razor also has built-in channels that evacuates hair and cream, which make clogging virtually impossible. Henson Shaving wants to produce the best razors, not the best razor business, so that means no plastics, no subscriptions, no proprietary blades, and no planned obsolescence."
},
{
"end_time": 5317.329,
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"start_time": 5300.947,
"text": " It's also extremely affordable. The Henson razor works with the standard dual edge blades that give you that old school shave with the benefits of this new school tech. It's time to say no to subscriptions and yes to a razor that'll last you a lifetime. Visit hensonshaving.com slash everything."
},
{
"end_time": 5346.34,
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"text": " If you use that code, you'll get two years worth of blades for free. Just make sure to add them to the cart. Plus 100 free blades when you head to H E N S O N S H A V I N G dot com slash everything and use the code everything. I think that second claim is probably right, but probably not universally and universally across the whole brain."
},
{
"end_time": 5370.913,
"index": 198,
"start_time": 5347.551,
"text": " Yeah, across people. Oh, across, well, both. I mean, I think in any given brain, it's probably not sensible to describe all the things going on in the brain as involved in implementing Bayesian inference. For the simple reason that some things can be pretty hardwired. I mean, that's one reason. There'll be other reasons too."
},
{
"end_time": 5396.118,
"index": 199,
"start_time": 5372.022,
"text": " and one cannot but you still can probably interpret it as doing as if it were doing Bayesian inference because you can always tell a story you can always say oh yeah you know I can describe these dynamics as they're compatible with the brain doing Bayesian inference but it's a different question from whether it's actually doing it okay and again this this is actually a pretty controversial thing too that that"
},
{
"end_time": 5425.794,
"index": 200,
"start_time": 5399.087,
"text": " You can find, I think there are lots of cases where things will look like exceptions to this rule. And they may well be accepted. A very kind of basic example of this is the phenomenon of adaptation and perception. That for instance, if I show you a load of"
},
{
"end_time": 5454.292,
"index": 201,
"start_time": 5426.664,
"text": " a load of lines of that orientation, let's say 45 degrees sloping up left, let's say. And then I show you a line of a different orientation. You will perceive it as further away from what I was showing you before. This is the opposite of the regression to the mean effect that I was describing earlier. So that so I wasn't being entirely comprehensive when we were talking about that adaptation."
},
{
"end_time": 5480.401,
"index": 202,
"start_time": 5455.93,
"text": " goes away from the mean. If you go towards the mean, that's like an example of what you would expect under Bayesian inference, because you're expecting that. So examples of perceptual adaptations seem to be anti-Bayesian, if you like. And so there's then been a lot of discussion about what that means. I mean, it's just a fact that"
},
{
"end_time": 5509.753,
"index": 203,
"start_time": 5480.794,
"text": " That's true. I mean, that's what adaptation does. And you can sort of understand it in terms of different neural populations getting fatigued or worn out. And so across the population, that's what you see. You can still tell a Bayesian story about it. I forget what it is now. But there are certainly things that it's not, I don't think the Bayesian brain hypothesis is this sort of magic solution to everything we see. But I think it's a very useful perspective"
},
{
"end_time": 5540.299,
"index": 204,
"start_time": 5510.52,
"text": " at that first level about it's a standard of optimality and I also think that a lot of perception in the brain and action can is I think probably is the brain implementing and approximating Bayesian inference. The other just last thing I want to say about that was when you were giving your counter examples of where you expected to see the pen and then it was where you were looking all along or"
},
{
"end_time": 5569.514,
"index": 205,
"start_time": 5540.469,
"text": " You expected to hear a word. There's a confusion is often made here because when people use Bayes' theory to talk about things, they will use words like expectation and belief and prediction and so on. These are not necessarily personal level things. It's not something you as a person need to believe or expect or predict. So if I talk about a Bayesian belief,"
},
{
"end_time": 5597.363,
"index": 206,
"start_time": 5570.009,
"text": " It makes as much sense to say that I as a person believe that Neil Armstrong landed on the moon, as it would make sense to say my visual cortex believes that light always comes from above. A Bayesian belief is a probability distribution, which means that it could very well be that your brain is doing Bayesian inference even though you as a person had a"
},
{
"end_time": 5620.862,
"index": 207,
"start_time": 5597.705,
"text": " expectation that turned out to be incompatible with what you see. Your visual cortex might be believing something different. I see. Can I just interject here a little bit? Is the Bayesian brain model in any way, can it be tied to mental disorders, like mood disorders, let's say severe depression? Because when we discuss ideas such as optimal,"
},
{
"end_time": 5648.66,
"index": 208,
"start_time": 5621.152,
"text": " optimal conditions well someone who is who's severely depressed clearly they're not in an optimal condition can can the Bayesian model sort of identify what what is going wrong here and perhaps alter even alter that suboptimal conscious experience any studies on that well let's first be careful because I don't want to to imply that"
},
{
"end_time": 5677.91,
"index": 209,
"start_time": 5649.07,
"text": " I mean, clearly being depressed, for instance, is not a great state to be in. So it's suboptimal for the person in terms of their lived experience. But I would worry a little bit about saying that there is a standard of optimal performance of the brain and then deviations from that are wrong and to be avoided. Optimality here simply means a sort of mathematical optimality about"
},
{
"end_time": 5697.056,
"index": 210,
"start_time": 5679.189,
"text": " the most rational way of combining sources of information that are uncertain. It can very well be that being perfectly optimal in that way is psychologically suboptimal. In fact, many people would argue that."
},
{
"end_time": 5724.224,
"index": 211,
"start_time": 5697.568,
"text": " that we have better psychological lives and perform better if we are slightly irrationally optimistic about things. So these two things can come apart and I think there is this general worry, I have this worry about this sort of reification of things like optimality from one language to another and we suddenly start making claims about people's psychological lives and"
},
{
"end_time": 5750.213,
"index": 212,
"start_time": 5725.316,
"text": " ethics and morals and things like that. There's a big gap. Having said that, you're absolutely right that this is a good framework for thinking about phenomena in psychiatric conditions, mental illness, other things too. Perhaps the best example, one of the oldest is in schizophrenia and psychosis. And we go back to hallucinations. What is a hallucination?"
},
{
"end_time": 5780.367,
"index": 213,
"start_time": 5751.169,
"text": " In the language we've been talking about now, hallucination can be usefully thought of as a Bayesian inference where your prior belief or your visual cortex's prior belief is unusually strong. So it's overwhelming the sensory data. So the conclusion the brain comes to is guided more by what the brain expects is there than what the physical signals from the world are saying."
},
{
"end_time": 5807.858,
"index": 214,
"start_time": 5781.34,
"text": " If you think that every perception is this balance between what we expect and what we get. Again, we had this example earlier of looking at faces in clouds. Everybody sort of has a minor hallucination going on there, partly because our brain comes preloaded with expectations to see faces everywhere. Face is a very important stimuli for us as human beings. So we see faces in clouds quite easily."
},
{
"end_time": 5835.913,
"index": 215,
"start_time": 5809.787,
"text": " When people are having hallucinations in, well, perhaps in in psychedelia, but also in psychosis, you can think of that then as again, that perceptual predictions are overwhelming the sensory data. And I think this is this is a really powerful approach. It's Paul Fletcher in Cambridge and Chris Frith in London pioneered this this way of thinking many years ago, and"
},
{
"end_time": 5865.998,
"index": 216,
"start_time": 5836.613,
"text": " And now people like Phil Corlett at Yale are taking it further because it makes very specific predictions. If somebody with psychosis is, if their symptoms are explained by this imbalance, then you could presumably put them into a very limited psychophysical situation where we can test in a very, if you like, boring way what the balance is between their"
},
{
"end_time": 5892.056,
"index": 217,
"start_time": 5867.227,
"text": " their expectations and their perception. We can basically just, and this experiment that Phil Corlett did, was to just associate a dim flash of light with a noise, but then very occasionally leave the flash of light out and then ask people what they perceived. And people with psychosis would perceive the flash of light, report the flash of light,"
},
{
"end_time": 5917.858,
"index": 218,
"start_time": 5892.466,
"text": " more often when it wasn't there than people without psychosis because you know the interpretation being they're expecting the flash of light and that expectation stronger in these people so it actually generates the experience more often and I really like this because it if you think about how medicine works you want to get away from"
},
{
"end_time": 5944.855,
"index": 219,
"start_time": 5919.292,
"text": " defining conditions purely based on the symptoms that people report and you want to get towards understanding what the underlying mechanisms are. It used to be people would have fever and that would be their disease. You know, they have fever and maybe a yellow fever or another fever, but that was it. And you treat it by, I don't know, blood letting or something. But once you understood that,"
},
{
"end_time": 5974.838,
"index": 220,
"start_time": 5945.691,
"text": " Fever is a symptom, but there's a mechanism that's giving rise to that fever, and that's an infection. You treat the infection, fever goes away. Medicine has always progressed like that, from getting underneath the surface level symptom description to what the underlying pathology is. And in psychiatry, this is still early days. If you look at the Diagnostic Statistical Manual in psychiatry, it's basically a big list of symptoms."
},
{
"end_time": 6004.565,
"index": 221,
"start_time": 5975.896,
"text": " And depending on what cluster of symptoms you have, that's what you got. But we're beginning to move beyond that now. And this is one example. Okay. Something like psychosis, one of the underlying abnormalities or aberrant processes is Bayesian belief updating in the brain. And that explains the symptoms, but it also means, well, maybe there are more targeted ways to develop"
},
{
"end_time": 6031.323,
"index": 222,
"start_time": 6004.753,
"text": " prognosis or therapy even. And so I think this is this is the whole area which we which is now called by computational psychiatry coming up with computational models of the symptoms in psychiatric conditions. So psychosis, schizophrenia is one. But then people also thinking about this in terms of things like depression as well, and also things which which I would rather label as"
},
{
"end_time": 6060.043,
"index": 223,
"start_time": 6031.971,
"text": " neurodiversity rather than psychiatric disorders, but things like autism, so conditions that are not psychiatric problems, but certainly involve people having different kinds of experiences. And again, what's actually underlying the surface level phenomena here, I can see how depression and psychosis might be related to a miscalibration of the Bayesian priors. How"
},
{
"end_time": 6086.664,
"index": 224,
"start_time": 6060.486,
"text": " What about other psychiatric conditions, like you mentioned autism? That one, I don't see how it's a mistake in how they're viewing the world. It seems to me to be more hardwired. Well, this is going to be clear that I don't think it should be described as a psychiatric condition autism. I think it's an example of neurodiversity. And so it's again, I think it is a very interesting example, because"
},
{
"end_time": 6118.217,
"index": 225,
"start_time": 6089.138,
"text": " typically when people are given the diagnosis or label of autism or being autism spectrum, it's often when some social difficulties become apparent. And so people typically have thought of it in terms of an issue with theory of mind that there's a difference in autistic people about the way in which they perceive the states of other people's minds."
},
{
"end_time": 6147.961,
"index": 226,
"start_time": 6119.821,
"text": " And that's been for a long time, sort of the general understanding of what autism is. But then if you look more carefully, closely, and people have always done this, because about what people with autism report about their lived experience, it's not just about theory of mind or anything like that."
},
{
"end_time": 6176.783,
"index": 227,
"start_time": 6148.268,
"text": " There are some very basic perceptual phenomena happening too. There's often this sensation of being overwhelmed by sensory data. Everything seems overwhelming in the sensory world. Loud noises are very disturbing. There's a sort of need to control, to make inputs more predictable. Things seem more unpredictable. And to me this, and to others, this begins to speak to"
},
{
"end_time": 6206.698,
"index": 228,
"start_time": 6178.78,
"text": " something going on that can be more usefully articulated in a sort of Bayesian language here. The brains of autistic people, they're dealing with uncertainty in a different way. They're not adapting to changing probabilities quite so well. There's a lot of hypotheses out there. The basic point is that we can again go much deeper than"
},
{
"end_time": 6236.834,
"index": 229,
"start_time": 6208.148,
"text": " how these conditions superficially present themselves to understand, well, there's something more basic going on about how these brains are processing sensory information that then these high level phenomena are built upon. Back to schizophrenia, actually, a lot of the symptoms of schizophrenia become clinically relevant when they become delusions, when people start having false beliefs about paranoia and"
},
{
"end_time": 6267.21,
"index": 230,
"start_time": 6237.602,
"text": " being controlled by the CIA or something like that. But these false beliefs can be understood as higher order inferences to explain away unusual perceptions. And so it's the perception that comes first, not the belief. And so you begin to understand that the primary pathology in something like schizophrenia is an alteration in perceptual ability. And that only then, later on as the condition progresses, does that"
},
{
"end_time": 6295.93,
"index": 231,
"start_time": 6267.637,
"text": " Does that become manifested in beliefs, in different kinds of beliefs? Speaking of, well, not speaking of, let's take attention. Gödel's incompleteness theorem. I'm curious to know what you see as the applicability or non-applicability of it with regard to how the brain operates. So someone like Penrose or Lucas would say that it implies that the brain is not purely computational in the way that we imagine computation, let's say in a Turing sense."
},
{
"end_time": 6325.725,
"index": 232,
"start_time": 6297.022,
"text": " because of so-and-so. I'm sure you know the argument. What do you see? What does Gödel's Incompleteness Theorem has? I don't think it has that much relevance, to be honest. I remember reading Penrose's book, The Empress in the Mind, about 30 years ago now, I think shortly after it came out, just at the beginning, when I was just about to go to college, waiting for this enlightenment about why it was"
},
{
"end_time": 6355.077,
"index": 233,
"start_time": 6325.998,
"text": " going to be relevant. And it's clearly a very important piece of mathematical philosophy, right? It's telling us that there are axioms with any given formal system that cannot be proven to be true within that formal system. And as I understand it was a sort of big blow against the Hilbert program of trying to bring closure to the mathematical explanations. And"
},
{
"end_time": 6377.875,
"index": 234,
"start_time": 6357.21,
"text": " But quite what that has to say about the brain, I've never been convinced that it has that much to say. And this is partly because, you know, I don't think the brain is a computer. And so the fact that"
},
{
"end_time": 6408.148,
"index": 235,
"start_time": 6378.609,
"text": " Think Verizon, the best 5G network is expensive? Think again. Bring in your AT&T or T-Mobile bill to a Verizon store today and"
},
{
"end_time": 6439.411,
"index": 236,
"start_time": 6411.015,
"text": " Sorry."
},
{
"end_time": 6468.933,
"index": 237,
"start_time": 6440.367,
"text": " I guess for me, Gödel's theorem, if you apply it to the brain, it may tell you that the brain is not a computer. On the reasoning that there are things that we can understand to be true."
},
{
"end_time": 6492.756,
"index": 238,
"start_time": 6470.998,
"text": " within a formal system where a proof of that doesn't necessarily exist. This is going way back because it's been a long time since I've thought about this, but firstly that doesn't seem that surprising because even if the brain were"
},
{
"end_time": 6524.292,
"index": 239,
"start_time": 6494.36,
"text": " a computer of this sort. We don't know quite exactly what kind of computer it is, so we don't quite know what sorts of true statements should be not establishable by the kind of computer that the brain might happen to be. But basically, I'm kind of happy with the idea that the brain is not a"
},
{
"end_time": 6550.503,
"index": 240,
"start_time": 6525.043,
"text": " does not operate according to these principles of logic, and that it doesn't reach true conclusions about truths by combining these logical operations in a particular way that Gödel's theorem rests on. Gödel's theorem is a sort of deduction, I think, isn't it? It's a real strong form of logic."
},
{
"end_time": 6579.087,
"index": 241,
"start_time": 6551.408,
"text": " That's fine. Does that put you at odds with some of your colleagues? Because as far as I understand, most of them believe that the brain is some computational device that could be wrong, could just have it by a set. No, I think you're right. I think that I don't know if it sets at odds, but but I, but well, I mean, firstly, I don't think it particularly the whole point about Goodell's theorem for Penrose is then made a claim about consciousness. Yeah. And that was a connection that was, to be honest, never very clear to me."
},
{
"end_time": 6604.377,
"index": 242,
"start_time": 6579.36,
"text": " It's sort of the idea that we consciously experience things that as being true or false, that we know cannot be proven that way by a system of logic through Gödel's theorem. So therefore consciousness is not a property of these kinds of formal systems. Again, fine, right?"
},
{
"end_time": 6634.343,
"index": 243,
"start_time": 6605.196,
"text": " It still might be the case that the brain does do some information processing. It still might be the case that it is just of a constrained or restricted kind. So I think you can have that. You can accept that the brain is an information processing device, but maybe it doesn't have the kind of class of universality for which Gödel's theorem becomes relevant. Not all computers have to be universal."
},
{
"end_time": 6663.66,
"index": 244,
"start_time": 6634.974,
"text": " But I do also worry that people use that language too loosely when they talk about the brain. It's a very easy thing to say that the brain processes information and that consciousness is a form of information processing of some sort that we just don't quite understand yet. Maybe, but... It speaks to mind uploading."
},
{
"end_time": 6690.674,
"index": 245,
"start_time": 6664.821,
"text": " Well, yeah, I mean, it's, to be honest, I think there's this, it's quite a big assumption that consciousness is to do with information processing and the brain is actually an organ of information processing. Yes, there is an indirectness between what sensory inputs do when they impact our retinas and our things and what the organism as a whole does."
},
{
"end_time": 6720.247,
"index": 246,
"start_time": 6692.619,
"text": " You can always apply information processing metaphorically. You can describe a system from a third person perspective as processing information. It's transforming inputs into outputs. We can describe inputs, we can describe outputs. And there's an indirect relate. But is that what the brain is actually doing? Is it exchanging symbols in some way? How is its mechanism actually working? Or is it just a very complicated bunch of levers and pulleys?"
},
{
"end_time": 6747.449,
"index": 247,
"start_time": 6721.288,
"text": " that look as if it's processing information. Does that difference make a difference? I think it does when you draw these kinds of implications from it. So as you just mentioned, if you believe that consciousness is a property of a particular form of information processing, then you might believe"
},
{
"end_time": 6777.142,
"index": 248,
"start_time": 6748.302,
"text": " that it doesn't matter what the substrate of that is, what is the physical mechanism that's underpinning this information processing. And you're not convinced that it's substrate independent? No, I'm not convinced. But I'm again, I'm disappointingly agnostic about it, right? I actually, I think that the only conscious, the only systems we know of confident in that are conscious are biological systems."
},
{
"end_time": 6796.544,
"index": 249,
"start_time": 6778.746,
"text": " It's difficult to come up with a good reason why that should be so. Why should it be that consciousness is restricted to things made out of neurons? But there's also many other levels of substrate independence. There are things like, well, maybe it doesn't matter quite what the"
},
{
"end_time": 6827.142,
"index": 250,
"start_time": 6798.046,
"text": " molecules are, whether they're carbon or silicon, but maybe the structure of the mechanism still matters. So theories like integrated information theory pick out this middle ground. For integrated information theory, the substrate doesn't matter in the sense that silicon is just as good as carbon, but the mechanism does matter. You can't have a feed-forward neural network without any recurrency. Be conscious. It doesn't. On that theory, that's ruled out."
},
{
"end_time": 6852.09,
"index": 251,
"start_time": 6827.722,
"text": " because it's a property of the mechanism. So there are many different ways in which things other than input-output mappings might turn out to be relevant. And the assumption that none of these things matter, I think, is a dangerous and weak assumption. And of course, that's the assumption on which these things like mind-uploading are based, that the idea that"
},
{
"end_time": 6869.394,
"index": 252,
"start_time": 6852.944,
"text": " It really doesn't matter that if I get the input output relations right, if the system is functionally identical, then I'm going to be conscious in my iPhone. I just don't think that's a safe way to think. Speaking of Tononi"
},
{
"end_time": 6897.927,
"index": 253,
"start_time": 6869.718,
"text": " I understand how psi can be measured in, let's say, toy examples in trivial, somewhat trivial, idealized states. I think you mean phi, by the way. Psi is very... Psi is his measure. Psi is like some sort of, you know, hokey stuff. OK, that's great. Although there may be a relationship, who knows, right? OK, so let's talk about phi. Is there a measure of phi that you have found in living humans? So phi in... Do you have to be living?"
},
{
"end_time": 6926.015,
"index": 254,
"start_time": 6899.462,
"text": " Yeah, they have to have dynamics. Is there a way of using neuroimaging to determine the phi of someone, let's say? The straight answer is yes, but it's not the same phi that Giulio would want to measure in his theory. There are approximations which I think he can measure. So phi mathematically is this measure of"
},
{
"end_time": 6957.688,
"index": 255,
"start_time": 6927.705,
"text": " How much information the whole of a system has about its evolution over time than the parts do considered independently. It's sort of a measure of emergence in this sense. You can also think of it a bit more loosely as a measure of combination of integration and information. The system is going to have high FI if it can enter more different states that make a difference for itself."
},
{
"end_time": 6986.664,
"index": 256,
"start_time": 6958.968,
"text": " So, the information has to be for the system itself and not for an external observer. So, it has to be integrated in that way. Now, for duotenoni, to really measure phi, there's a problem in that to quantify the amount of information a system is generating by being in a particular state,"
},
{
"end_time": 7016.22,
"index": 257,
"start_time": 6987.381,
"text": " Technically, you need to know all the possible states the system could have been in, even if it's never been in any of those states. In practice, this is nearly always impossible to know. And it's impossible because we don't have a high enough resolution or for some other reason? Well, for some other reason. I mean, even if you could measure everything in precise detail, there are only certain systems, I think there are gothic systems where I forget my physics terminology now, but most systems will not"
},
{
"end_time": 7046.067,
"index": 258,
"start_time": 7016.357,
"text": " Unless you push them in some way, they may not explore all the possible states they could be in. They only explore a subset of their state space. And so you've got to push a system in all possible ways to figure out what all possible states it could be in are. And you can't do that just by having high resolution brain imaging. What you can do, let's assume you've got this fancy new technology you can"
},
{
"end_time": 7075.776,
"index": 259,
"start_time": 7046.647,
"text": " measure with arbitrarily high spatial and temporal resolution, you can measure now an approximation to find. There's still massive difficulties, computational difficulties in considering how you cut all these, what the right granularity of time and spaces that gives a maximum value of it and how you cut the system up to find what partition makes the biggest difference between the whole and the parts. There are massive problems."
},
{
"end_time": 7105.06,
"index": 260,
"start_time": 7076.357,
"text": " But you can do it. And with my colleagues here, with Adam Barrett in particular, and Pedro Mediano in London, we've been developing for nearly 10 years now, some approximations to find that capture some of the spirit of it, that it's a measure of combined integration information, but which you can practically apply to brain imaging data. So that's certainly possible, but it has to be recognized that they are"
},
{
"end_time": 7131.186,
"index": 261,
"start_time": 7105.589,
"text": " approximations. As of now, they don't work very well when we apply them to actual data in the sense that they're pretty insensitive to, or rather they're very noisy. You can change subtle things in a system and then the measure changes quite a lot."
},
{
"end_time": 7150.452,
"index": 262,
"start_time": 7131.698,
"text": " So I wouldn't have very much confidence applying these measures to empirical data, although it's certainly something we're still working on. I was reading a paper by Peter Lush a few months ago before I had researched you at all. Turns out you're a co-author on it, so that's pretty cool. It was about the rubber hand illusion."
},
{
"end_time": 7165.776,
"index": 263,
"start_time": 7150.776,
"text": " and imaginative suggestion, demand characteristics, and phenomenological control. I don't recall it precisely and I wasn't sure about the relationship between the three. As far as I understand demand characteristics serve as an implicit imaginative suggestion and"
},
{
"end_time": 7180.947,
"index": 264,
"start_time": 7166.049,
"text": " As far as I understand, phenomenological control is the degree to which you can act on that suggestion, or the degree to which you can act on your expectation. Is this something like that? Do you mind just, if you know what you're talking about, outline it for the audience because I found it extremely interesting."
},
{
"end_time": 7209.599,
"index": 265,
"start_time": 7181.715,
"text": " Yeah, this is a switching of gears again, but I'm glad you brought it up. There's a lot of terminology there. In one sense, they're all vaguely unsuccessful attempts to avoid saying hypnosis, because hypnosis has all this unfortunate historical baggage. I think there was the word hypnotizability in the paper. It'll be in there. But you have these, so let's take them one by one. So demand characteristics is a phenomenon that psychologists have known about forever, since the 60s, at least. It was formalized then, but I'm sure people knew about it before."
},
{
"end_time": 7237.193,
"index": 266,
"start_time": 7209.838,
"text": " This is the idea that if you're doing a psychological experiment, oftentimes your subjects might implicitly or even explicitly know what you're trying to, what the right answer is, so to speak, and either just deliberately tell you what you were expecting to hear because they don't want to disappoint the experimenter or unconsciously actually have that sort of experience. If you, if you expect,"
},
{
"end_time": 7265.691,
"index": 267,
"start_time": 7238.251,
"text": " If the context of an experiment is strongly leading you to have a particular kind of experience in one condition rather than another, then you may well have that experience. And so in psychology, it's always been important to rule out demand characteristics if you want to say that something else is responsible, which basically means trying to say that people don't have different expectations for different experimental conditions."
},
{
"end_time": 7292.807,
"index": 268,
"start_time": 7266.817,
"text": " And then if you still see a difference, then you can say, well, it's not because of their implicit expectations about what should happen. And then we get to suggestibility, imaginative suggestibility, hypnotic suggestibility. These are this speaks to there's a there's quite reliable individual differences."
},
{
"end_time": 7322.568,
"index": 269,
"start_time": 7293.353,
"text": " in how hypnotically suggestible people are. And by suggestible here, I mean something like you can be asked to experience something like a fly crawling up your arm or something like that. And you might have, you might actually start to experience that. Um, you know, your hands are being drawn together. There are ways in which people vary in the extent to which a suggestion from a, from a third person can induce an experience."
},
{
"end_time": 7345.708,
"index": 270,
"start_time": 7323.183,
"text": " That's what we mean by hypnotizability here. So it's not the kind of Darren Brown big magic stage magic thing. Well, that's fascinating too. It's more like just how much can your experience be influenced by what I say? And people vary a lot in this. You're in the YouTube, so Darren Brown is a huge celebrity, right? He's brilliant. Actually, he's a"
},
{
"end_time": 7373.729,
"index": 271,
"start_time": 7346.391,
"text": " So now you can start to see that if you've got an experiment where there might be demand characteristics going on such that the setup of the experiment leads you to expect some sort of experience in one condition but not another,"
},
{
"end_time": 7401.459,
"index": 272,
"start_time": 7374.275,
"text": " If you're highly hypnotizable, highly suggestible, the demand characteristics might have a stronger effect. I see. Because they basically act as a suggestion. And if you're more susceptible to suggestions, they're going to have a stronger effect. Now, the third piece is this term phenomenological control, which Peter Lush and Zoltan Dienas, my other colleague at Sussex, they sort of introduced this term basically to try and"
},
{
"end_time": 7426.408,
"index": 273,
"start_time": 7402.415,
"text": " Emphasize firstly that these suggestions can affect your experience hence phenomenological phenomenology and The idea of control is that it's the subjects you yourself. I you know, I give you the suggestion but then you're Controlling you're generating your experience conscious even though you're not aware of doing it. Yeah, that that's the point so I Can induce you to experience something if you're highly suggestible or"
},
{
"end_time": 7456.442,
"index": 274,
"start_time": 7426.937,
"text": " You're generating yourself, but you're not aware that you're doing it. It sounds like the placebo is related to the placebo effect. It's very related, right? Again, people who respond to the placebo effect, arguably, and there's some evidence that they're more highly hypnotizable. They're more suggestible. They're changing their experience in response to a suggestion. So there's this very big, typically uncontrolled variable in a lot of experiments of hypnotizability."
},
{
"end_time": 7479.087,
"index": 275,
"start_time": 7457.295,
"text": " traits, phenomenological control, suggestibility, take your pick. And this matters if your experiment involves demand characteristics, because now the results you're going to get will depend on who you test. And so we've thought this is work led by Peter and Zoltan and Warwick, who I mentioned earlier, Warwick Roseboom, who's worked on the time perception stuff too."
},
{
"end_time": 7494.206,
"index": 276,
"start_time": 7480.657,
"text": " So this is what's going on in the rubber hand illusion. Rubber hand illusion is a very famous thing. I mentioned it. I demonstrate it in my TED talk. And I tell the old story. So this is something where I've had to change my mind about it a little bit. You tell the old story."
},
{
"end_time": 7520.179,
"index": 277,
"start_time": 7494.838,
"text": " Yeah, the pre phenomenological control. This is why I wrote down, because I remember you referencing the rubber hand illusion plenty. And I thought, okay, are you using this as a basis for your model? And I know that there's some holes that are poked in the rubber hand theory, at least by Peter lush. So I was like, oh, hey, that sounds interesting. But then I found out, wait, you co author that paper. So you should know about this. Am I correct in my interpretation of it? No, I mean, we're in fact, we're"
},
{
"end_time": 7550.589,
"index": 278,
"start_time": 7520.623,
"text": " We should change our minds, right? I mean, if I didn't change my mind about something, I wouldn't be a good scientist, right? So, so yeah, this is work. So that talk was from 2017. And this work in rubber hand illusion started maybe in 2018 or 2019. So but actually, they both fit with this general story. So this rubber hand illusion is this idea that my experience of I can I can change my experience of body ownership of what is my body in some fairly simple lab based way. If"
},
{
"end_time": 7578.831,
"index": 279,
"start_time": 7550.981,
"text": " If I put a rubber hand in front of you and your real hand is hidden from view and I stroke the rubber hand simultaneously with the real hand. So you're seeing stroking on the hand. You're looking at her hands. It's a rubber hand, but you're seeing stroke and you're feeling it too. Cause I'm stroking a real hand. Then for some people you start to have this weird experience that this hand is somehow part of your body, even though you know it's not. Um, and so simple story explanation for that."
},
{
"end_time": 7599.411,
"index": 280,
"start_time": 7579.189,
"text": " is that it's just multi-basian multi-sensory integration that the brain sees touch and it feels touch and it's putting these things together and decides that's my hand. But there's this other factor which is that's a situation which is going to very strongly induce"
},
{
"end_time": 7624.906,
"index": 281,
"start_time": 7599.838,
"text": " demand characteristics. You're seeing something looks like a hand and you're being stroked and then the experimenter asks you, does that feel like your hand? You can see it's going to set up that expectation. And so what Peter's work beautifully did was to show that in fact, individual differences in imaginative suggestion and suggestibility correlate with how strong the rubber hand illusion is. I see."
},
{
"end_time": 7653.933,
"index": 282,
"start_time": 7625.299,
"text": " And he also showed that typically people use as a control, they stroke the rubber hand out of time with a real hand. Yeah. So now this is going to break this multi-sensory integration because now you feel touch, but it's no longer aligned with the touch that you're seeing. And what happens? Well, people experience it much less. Yeah. But the point is people also expect to experience it much less. If you ask just people, what would they expect to experience when it's out of time?"
},
{
"end_time": 7681.254,
"index": 283,
"start_time": 7654.718,
"text": " They say, well, I wouldn't expect to experience it then. So it's not a good control for demand characteristics because what you expect to experience differs in both cases. I thought that what you did was great with the pulsing of the heart because I don't imagine that someone would think or would even be conscious of how their heart is pulsing to be able to associate the one that is in line with. Okay."
},
{
"end_time": 7691.34,
"index": 284,
"start_time": 7681.698,
"text": " Does that not show that it's not purely the demand characteristics or the imaginative suggestion because you don't know you don't have access to how your heart is here that sound."
},
{
"end_time": 7718.404,
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"start_time": 7692.261,
"text": " That's the sweet sound of success with Shopify. Shopify is the all-encompassing commerce platform that's with you from the first flicker of an idea to the moment you realize you're running a global enterprise. Whether it's handcrafted jewelry or high-tech gadgets, Shopify supports you at every point of sale, both online and in person. They streamline the process with the internet's best converting checkout, making it 36% more effective than other leading platforms."
},
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"text": " There's also something called Shopify Magic, your AI-powered assistant that's like an all-star team member working tirelessly behind the scenes. What I find fascinating about Shopify is how it scales with your ambition. No matter how big you want to grow, Shopify gives you everything you need to take control and take your business to the next level. Join the ranks of businesses in 175 countries that have made Shopify the backbone"
},
{
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"start_time": 7744.48,
"text": " of their commerce. Shopify, by the way, powers 10% of all e-commerce in the United States, including huge names like Allbirds, Rothy's, and Brooklyn. If you ever need help, their award-winning support is like having a mentor that's just a click away. Now, are you ready to start your own success story? Sign up for a $1 per month trial period at shopify.com slash theories, all lowercase."
},
{
"end_time": 7799.309,
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"text": " Go to Shopify.com slash theories now to grow your business no matter what stage you're in Shopify.com slash theories. You do right away, but you're not paying. So I think I think unfortunately not in two different ways. One way is that in fact, uh, suggestion effects can influence basic physiology as well. It's not just limited to what you might subjectively report about your experience. You can induce physiological response"
},
{
"end_time": 7829.599,
"index": 289,
"start_time": 7803.046,
"text": " And the other thing is, you know, get that experiment again. So I was really and still am. I think it's a great experiment that we did at the time. But we did not look for individual differences in people suggestibility. This was like before we did this new work. So we did it a small family. The problem is this makes experiments in this area really hard because to"
},
{
"end_time": 7853.166,
"index": 290,
"start_time": 7830.265,
"text": " Peter's experiment where we measured hypnotizability and then looked at the rubber hand illusion. We did the experiment, or he did the experiment, well, a bunch of people did on, I forget, was it 430 or 340? Hundreds of people. Normally these experiments are done on groups of like 20 or something like that. And so"
},
{
"end_time": 7882.91,
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"start_time": 7855.094,
"text": " I don't know. In this experiment that you're referring to, where what we did was instead of stroking the hand, we gave people a virtual hand and it flashed either in time or out of time with their heartbeat. And again, we found that people experienced it more as their own hand when the flashing was in time with their heartbeat. So sort of what we called a cardiovascular, cardiovascular something, version of the rubber hand illusion, intraceptive version."
},
{
"end_time": 7908.473,
"index": 292,
"start_time": 7884.053,
"text": " I don't know to what extent that's driven by suggestibility. I just don't know because we didn't measure it. And so we need to do it again. And we haven't yet. I'm also wondering, and I'm just thinking out loud here, if there is any utility to test this experiment when the participants are on psychedelics,"
},
{
"end_time": 7937.329,
"index": 293,
"start_time": 7908.592,
"text": " Yeah, so we've done some work in collaboration now with the group at Imperial College London led by Robin Cart Harris on what happens in the brain during psychedelics."
},
{
"end_time": 7963.592,
"index": 294,
"start_time": 7937.944,
"text": " And there are lots of interesting differences. One of the challenges is that when someone's on a large dose of psychedelics, they can't really do anything. They can lie in a brain scanner, but you can't get them to do an experiment and press buttons and report what's going on."
},
{
"end_time": 7988.012,
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"start_time": 7964.36,
"text": " One of the things I'm excited about is the potential for actually research in using microdosing here. So if you give people very small doses, sure, they don't have the big vivid hallucinations. Any differences in the brain are going to be correspondingly more subtle. But you have the big advantage that people can still do experiments. So I'd certainly like to"
},
{
"end_time": 8015.026,
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"start_time": 7988.319,
"text": " I think that's a very rich vein of work to follow. By the way, just to connect those two points, there was a lovely paper, I think, by Olson and colleagues from last year, where they claimed to have induced a psychedelic experience through hypnotic suggestion. It's called tripping on nothing. And they sort of set up the whole context, have a very nice relaxing lobby area and"
},
{
"end_time": 8042.449,
"index": 297,
"start_time": 8015.299,
"text": " People come in fully believing they're going to be taking part in some experiment with psilocybin and then they don't get any, but they're still led to believe that they have got it and then they often report all these hallucinations and things going on. So potentially you can even induce psychedelic effects given strong enough expectations about what's going on. Now, of course, I would say there's probably still going to be a difference between"
},
{
"end_time": 8069.462,
"index": 298,
"start_time": 8043.609,
"text": " What insights have you found from any of your psychedelic experiences, if you can talk about it, that you feel like were, let's say, worldview shattering or worldview forming? If anything, it was more reassuring because the thing is,"
},
{
"end_time": 8099.002,
"index": 299,
"start_time": 8071.271,
"text": " A lot of my work over the years has been about trying to understand perception as this kind of construction, this perceptual best guess. We've been talking about examples of seeing faces in clouds and all these effects that fit very comfortably with this view of how the brain works and how it does perception. So you think when you're on psychedelics, you're temporarily shifting with the Bayesian priors? Yeah, I think so. I think it sort of makes sense that way. Firstly, it gives you very, very"
},
{
"end_time": 8129.445,
"index": 300,
"start_time": 8099.462,
"text": " media insight that your perceptual world is a construction of some sort, you know, it starts departing from what it used to be quite, quite quickly. And it's interesting, people can have very different, I think, take different lessons from experiences like this, depending on their prior beliefs about them again. So if people believe that there's some sort of, some people might believe that psychedelics are evidence for a more immaterial"
},
{
"end_time": 8159.701,
"index": 301,
"start_time": 8129.77,
"text": " Because you suddenly depart from yourself, you don't experience yourself so much and so you might think, well, this is good evidence that consciousness is not this thing created by my brain somewhere behind my eyes. But for me, you also might reinforce beliefs and things like panpsychism, that consciousness is everywhere because the whole world seems to be alive and"
},
{
"end_time": 8188.114,
"index": 302,
"start_time": 8160.026,
"text": " vivid with meaning. But the other way to think of it is that if you come, say, somebody like me with a prior belief that the brain is the organ of experience, it's just more evidence for that because you mess with the brain in a very straightforward way. You just activate these serotonin receptors and bang, your experience of the world and the self massively changes. So I sort of interpret it as very strong evidence for the material basis of our conscious lives."
},
{
"end_time": 8218.251,
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"start_time": 8188.319,
"text": " What do you make of Daniel Dennett's claims of, well, let's say Daniel Dennett's view of consciousness. Have you read his Explaining Consciousness book? I always find it insightful to know how, let's say, luminaries like yourself and others disagree. Well, Dennett is the luminary in this group. I started reading his stuff again at a reasonably early stage. So in the early 90s, I was lucky to read it, Consciousness Explained. And it's a remarkable book."
},
{
"end_time": 8246.561,
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"start_time": 8218.985,
"text": " And, you know, I have been a lot inspired by Danit over the years. And I agree, I think, to a large extent, but maybe not the whole way. But that might partly be because I found it quite difficult to know what the whole way actually means for Danit."
},
{
"end_time": 8273.831,
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"start_time": 8247.483,
"text": " Meaning you're unsure of what his viewpoints are? Well, I mean, I've had many conversations with him and I know there's a lot of... So one thing that I very much like about his ideas is this sort of idea about multiple drafts and center of narrative gravity and this sort of idea that"
},
{
"end_time": 8303.234,
"index": 306,
"start_time": 8274.411,
"text": " the self, the narrative self, this identity that we have, the thoughts that we think that it's not some sort of internal essence of self. There's just many things going on and we kind of construct our experience of being a continuous self. He's also, for me anyway, bang on about some of the mistakes that people make when they think about perceptual experience. So for instance,"
},
{
"end_time": 8333.985,
"index": 307,
"start_time": 8303.985,
"text": " He's, he's, he's very much. Actually, I will tell you, I'll tell you one story because he was at the, when I gave my TED talk in 2017, he was in the audience. And I was massively terrified giving this talk. It's a terrifying experience. Oh, you looked calm on stage. Yeah, it's a totally terrifying experience. But I was most terrified of the fact that then it was in the audience and wonder what he was going to think of it."
},
{
"end_time": 8362.534,
"index": 308,
"start_time": 8334.787,
"text": " And he was very kind and he said it was almost perfect. And okay, what's the, what's the problem? He said, well, you said, like a father figure. He said, it's not good enough. No, he was, it was, it was, well, he picked out precisely the mistake. He wasn't to know about the rubber hand illusion stuff, right? That wasn't mistaken. Nobody knew about that. We hadn't done the work."
},
{
"end_time": 8389.172,
"index": 309,
"start_time": 8363.831,
"text": " I'd said as part of the talk this idea of conscious perception as like an inner movie. And I can't remember the precise words I use now. I used to know them totally by heart. But this idea that I describe this multimodal, fully immersive inner movie as a description of what perceptual experience is like. And that's what he said."
},
{
"end_time": 8410.845,
"index": 310,
"start_time": 8389.514,
"text": " he doesn't like that because it implies there's a little person in your head viewing it exactly exactly it implies even though i didn't mean it and i don't believe it just that linguistic slip it sort of it gives that impression it's easy to interpret that way and it might speak that i still fully hadn't grasped that point if you speak of an inner movie you imply"
},
{
"end_time": 8439.343,
"index": 311,
"start_time": 8411.203,
"text": " somebody watching the movie. No, there is no in the movie. Right, and that just begs the question. But I do recall, I do recall Dennis saying that it's okay to have a little person inside your brain watching the movie as long as that little person is another one. And it doesn't regress infinitely, because each little person can be different than the last. Do you remember this? Do you know this argument? Not, not really. I just think it's easier to do away with that argument at all. Yeah, there's no need for it. It's a it's a solution for that there's no problem that that"
},
{
"end_time": 8470.179,
"index": 312,
"start_time": 8440.384,
"text": " It's a solution to a problem that doesn't exist. Why would you need an inner homunculus anyway? Yes, we do have what we can call metacognitive processes. So I can make judgments about my conscious experiences. I can tell you whether I'm confident or not, or I can tell you whether I can reflect on and evaluate things that happen. But that doesn't mean there's a sort of inner observer. It just means there are hierarchical"
},
{
"end_time": 8494.394,
"index": 313,
"start_time": 8470.879,
"text": " organize that there's a hierarchical organization of my cognitive architecture um so yeah so he's certainly he's always i've always found him very on point about picking up on errors like that where i've never been entirely clear is these claims about"
},
{
"end_time": 8524.053,
"index": 314,
"start_time": 8496.374,
"text": " the extent to which we're mistaken about what it is we're trying to explain when we try to explain consciousness. He's often criticized or understood as saying that qualia don't exist. I'm not sure that that's what he means. I think it's entirely right to say that qualia, the redness of red, the painfulness of pain, are not what we think they are."
},
{
"end_time": 8552.056,
"index": 315,
"start_time": 8524.531,
"text": " But that doesn't necessarily mean they don't exist. But yeah, I mean, for me, he's definitely one of the people I still always learn from every time I speak to. And it's been an interesting talking to him and seeing how he's talking more also in terms of the brain these days and trying to put his ideas"
},
{
"end_time": 8576.715,
"index": 316,
"start_time": 8552.688,
"text": " within that framework, which I think is a really interesting project. And do you agree with his conception of free will, the compatibilist approach? I'm a compatibilist. Yeah. I mean, I think free will is another kind of perceptual experience. And I think this whole debate about determinism is totally irrelevant to the understanding of free will. I'm trying to get it."
},
{
"end_time": 8603.848,
"index": 317,
"start_time": 8577.09,
"text": " Dennis on the podcast, he said that he's busy writing a book, so he can't come on. I'm also trying to get Douglas Hofstadter. What are your views on Douglas Hofstadter's model of consciousness? I don't know him personally, and I've read only really the amazing Gertrude Bloch. It's one of the best books. Everybody should read that. It's phenomenal. It's just playful. What I take from that is just this credible"
},
{
"end_time": 8633.66,
"index": 318,
"start_time": 8604.36,
"text": " Playfulness, creativity. I have it right here. I keep only three books beside me or four books. It's one of them. Yeah, that's one of them. I don't know if you know this show, the Desert Island Discs. We have it on the radio here in the UK. And the idea has been going on for like decades. And the idea is you... What are the eight songs that you would take with you if you were getting banished to a desert island never to return? You can only take eight tracks."
},
{
"end_time": 8663.899,
"index": 319,
"start_time": 8634.121,
"text": " And then you're also allowed, so most people in England spend half their lives figuring out what these eight tracks are going to be just in case they get invited onto the show at some point and you want to be ready. But you're also allowed to take a book. Cool. And so for you, that would be definitely, well, I wouldn't say it would be the one, but it would certainly be up there. I haven't made a decision about the book yet. But it's, so I love the way it just create, it playfully explores our intuitions about what cognition is, what mind is, what"
},
{
"end_time": 8689.224,
"index": 320,
"start_time": 8664.138,
"text": " Explanations in biology physics consistent. I think it's I think it's synopsis. He's a genius sort of insights. Yeah, have you read his analogy book? I Haven't I haven't it's a great one. It's a but it's a far too long. Sometimes it goes through lists and lists What I find it to be somewhat tedious. Okay. So what are your views on his views of consciousness? Where do you agree disagree? I"
},
{
"end_time": 8703.763,
"index": 321,
"start_time": 8691.254,
"text": " Well, it's a tricky question, because to be honest, I would be hard pressed to articulate what they are. I mean, to me, he talks about strange loops and things like that."
},
{
"end_time": 8733.285,
"index": 322,
"start_time": 8704.002,
"text": " This is a real good story about Bronx and his dad Ryan, real United Airlines customers. We were returning home and one of the flight attendants asked Bronx if he wanted to see the flight deck and meet Kath and Andrew. I got to sit in the driver's seat. I grew up in an aviation family and seeing Bronx kind of reminded me of myself when I was that age. That's Andrew, a real United pilot. These small interactions can shape a kid's future. It felt like I was the captain. Allowing my son to see the flight deck will stick with us forever. That's how good leads the way."
},
{
"end_time": 8765.64,
"index": 323,
"start_time": 8738.268,
"text": " Yeah, I don't have a particular strong view because to me I've always just associated him with these things about language, recursion, all these playful insights. So I don't think he's, as far as I know, has not come into my radar specifically about consciousness, more about what's self-consistent and what we think of as the self. When you were saying that the homunculus, it's a foolish model in some ways,"
},
{
"end_time": 8793.422,
"index": 324,
"start_time": 8766.698,
"text": " What about global workspace theory? As far as I understand, I don't know much about it. I just had a cursory glance at it. It sounds like there's a homunculus because there's something that's viewing or there's a... Well, you can explain it much better than I, but what are your views on the global workspace theory? So the global workspace theory is one of the sort of most popular theories in consciousness science, neuroscientific theories these days. It's first developed by Bernie Baas and"
},
{
"end_time": 8821.749,
"index": 325,
"start_time": 8793.66,
"text": " taken on mainly by Stander Haim in Paris, a neuroscientist. And it makes a very simple sort of proposal that what we are conscious of, the contents of our consciousness, they become conscious in virtue of being broadcast in this workspace in the brain that gives them access to many different cognitive processes, which is why I'm conscious of this glass of water means"
},
{
"end_time": 8851.323,
"index": 326,
"start_time": 8822.551,
"text": " I can do many things now in virtue of being conscious of it. I can drink it. I can tip it over the computer. I can take it to the kitchen. I can put it down again, drink from it. I can talk about it. And so that whatever in my brain is representing the perception of that glass has access to all these different flexible cognitive processes. And the global workspace theory, it's that process of"
},
{
"end_time": 8869.258,
"index": 327,
"start_time": 8851.664,
"text": " being available, broadcasted around this workspace that endows that perception with the property of being conscious. The analogy, I think it's done it again, uses the analogy fame in the brain for that."
},
{
"end_time": 8896.596,
"index": 328,
"start_time": 8869.838,
"text": " Fame in the brain? Fame in the brain. So something becomes famous within the brain. All other parts of the brain know about it. Suddenly, my auditory cortex knows about it. My language centers know about it. My motor cortex knows about it. It's famous. There's a cup. There's a glass of water. Hooray! Everybody can see it. It's famous. And that fame in the brain underwrites conscious perception. So that's the claim."
},
{
"end_time": 8923.49,
"index": 329,
"start_time": 8897.739,
"text": " The nice thing about it is it explains a lot of functional properties we associate with consciousness because indeed there are things I can do when I'm conscious of something that I can't when I'm not. And this flexible action is central to that. It's also testable because you can put people in brain scanners and change, present them with stimuli and vary whether they're consciously perceived or not. And you can look for"
},
{
"end_time": 8953.985,
"index": 330,
"start_time": 8924.206,
"text": " Is there this ignition of this global workspace in the brain when they're conscious? And many experiments would say there is. The issue with it is that it's not for me explaining a great deal about, and as we sort of begin to wrap up, we're back where we started, which is with phenomenology. So the fact that something is famous in the global workspace explains a lot about what we can do behaviorally and functionally"
},
{
"end_time": 8981.22,
"index": 331,
"start_time": 8954.599,
"text": " But it doesn't really explain to me, at least, well, why is this visual experience the way it is? The phenomenology of this visual experience has a character. Just being famous in the global workspace doesn't really explain that. It also is not going to address the hard problem of consciousness. Yeah, that's what I'm thinking. No one would claim that it is. But there's this often inverse relationship. It has a benefit of being eminently testable."
},
{
"end_time": 9010.913,
"index": 332,
"start_time": 8982.005,
"text": " And although, you know, you can finess and say, well, the global workspace is wherever you find it in the brain. And there are problems because how do I separate the signature of a workspace being active from simply my consciously reporting something has happened? Maybe the difference I'm seeing in the brain is just the difference in my verbal report rather than in the mechanisms that give rise to the experience. So there are some tough questions there too, but it's"
},
{
"end_time": 9034.787,
"index": 333,
"start_time": 9011.544,
"text": " It's an appealing theory. I don't focus on it because for me I want to focus on what kinds of mechanisms explain phenomenology and for me the Bayesian perspective is much more interesting. Faraz, why don't you ask a question to wrap up and then I'll ask my last question as well. First of all, it has been a fascinating talk. Thank you so much for this conversation. Thank you, it's been great."
},
{
"end_time": 9063.933,
"index": 334,
"start_time": 9035.145,
"text": " Yes. I thought it was going to be half an hour. It's certainly not half an hour. I'm sure our audience... Our perception of time has changed. Yes, it has. Just to wrap things up, maybe very briefly, if you could just let us know, maybe... Do you consider yourself as someone who looks at the world through a pragmatic lens as opposed to, let's say, maybe an objectivist lens? Because, you know, I always look at the world"
},
{
"end_time": 9090.162,
"index": 335,
"start_time": 9064.155,
"text": " I think there are different frameworks from which we can choose to look at the world. And to me, the pragmatic approach seems to be the one that matches really nicely with the evolutionary perspective. So I'm just wondering what your thoughts are on this. Very briefly, I know it's been a long time. Do you mean as a scientist or as a sort of person going about my daily life here? Do you think there's a"
},
{
"end_time": 9120.384,
"index": 336,
"start_time": 9090.742,
"text": " I suppose both would be interesting. As a scientist, it makes sense that you might want to take a more objectivist approach, but maybe as a person could be uninteresting. Well, I think there's always a blend, right? I mean, even as a scientist, there's a sort of objectivity is an ideal, right? You don't get there and much philosophy of science emphasizes how in practice pragmatic it is. You've got to do experiments. You come up with testable hypotheses and you don't have a kind of complete"
},
{
"end_time": 9147.108,
"index": 337,
"start_time": 9121.715,
"text": " It's not a hypothesis test ruled out either. It's sort of what ideas are more... Lakatos talks about experimental fecundity, what frameworks give rise to experimental predictions. And so, yeah, I think scientifically I'm quite pragmatic as well. I want to focus on areas of the problem where progress is conceivable."
},
{
"end_time": 9177.892,
"index": 338,
"start_time": 9148.78,
"text": " Which is why I don't focus on coming up with a trying to think up some Eureka solution to the heart problem consciousness. I don't see if I can get there by doing stuff that can be done. And yeah, I guess that's the answer to say the other question part of your is that part of the reason why you dislike the heart problem just because of ostensible intractability? I don't dislike it at all. And you know, I think I think it just it crystallizes in a very, very"
},
{
"end_time": 9207.841,
"index": 339,
"start_time": 9178.78,
"text": " important way, an intuition about consciousness and a metaphysical challenge for explanations. It's just that I don't think addressing it head on is the most pragmatic, productive path for consciousness science to follow. Okay, so I have quite a few questions. I'm going to list them and then you could just choose one. Whichever one feels like it would give you the most bang for the buck."
},
{
"end_time": 9235.998,
"index": 340,
"start_time": 9208.78,
"text": " I was curious you mentioned Grainger causality and I and you said that it wasn't used often in neuroscience And I want to know why is that the case then okay another question was the relationship between consciousness and intelligence not the way that Intelligence is used when people say artificial intelligence, but more like IQ the neuroscientific IQ And I was curious if there's been any tests where you give someone anesthesia How much anesthesia is required is proportional to the IQ of the person so that is one way of testing?"
},
{
"end_time": 9265.742,
"index": 341,
"start_time": 9236.869,
"text": " Is someone who has a higher intelligence more conscious in some sense? Okay, so I was going to ask you, okay, the one I wanted to know about your opinion on Bach's theories, Yoshabach. There's a slide in your presentation, I believe it was about the free energy principle and how it relates to... Hold on, you just picked the one you want me to answer. Okay, let's get back to artificial intelligence because you have a PhD in it. There's different architectures, some of the famous ones like GAN, convolutional,"
},
{
"end_time": 9292.637,
"index": 342,
"start_time": 9266.561,
"text": " Now, Yoshibok said that one of the ways that the GAN, that the Generative Adversarial Network, relates to the brain is in dreams. He thinks that dreams are like your brain testing you at your weakest point, almost like the adversary tests. Okay, so you get the idea. Now I'm curious. There's GANs, there's Convolutional Recurrent LSTMs, there's Transformer, and Boltzmann, let's say. That's right."
},
{
"end_time": 9323.046,
"index": 343,
"start_time": 9294.07,
"text": " Are these different architectures, do you see them as related to different modules in the brain? Much like Yocha said, hey, well, the GaN might be somewhat related to dreams. Is it like the convolutionals is how we, it's a visual perception and it's pretty much that. Transformer is your ability to generate dialogue. Okay, can we pick a different question? Okay. I'm kidding. I'm kidding. Let's go with that. We'll have that one. We'll take it a little wider. Why is that a difficult question to answer?"
},
{
"end_time": 9346.101,
"index": 344,
"start_time": 9323.353,
"text": " It's kind of difficult. I mean, so yeah, my PhD in AI was quite some time ago, but we're actually still working on it. In fact, working on it more and more these days, again, with some super smart colleagues and grad students. And I think for the reason you just mentioned, because we have this, I think, so it's easy to say,"
},
{
"end_time": 9375.64,
"index": 345,
"start_time": 9347.671,
"text": " that the brain is making predictions about the causes of sensory data and that's what we perceive and it's doing some sort of Bayesian inference. So, but exactly how it's doing it and exactly how you can collect evidence to test these ideas of exactly what's going on depends on having much more sophisticated computational model of this process. So,"
},
{
"end_time": 9407.193,
"index": 346,
"start_time": 9377.927,
"text": " Which is why I'm very interested in these different classes of network. What can they explain about perception and behavior? How well do they map on to what we know, what we can measure in the brain? And actually the other way around, can we actually develop better machine learning architectures through understanding more about how the brain does these sorts of things? And there's good example. One of the things we're working on there is, for instance,"
},
{
"end_time": 9437.927,
"index": 347,
"start_time": 9408.114,
"text": " Most convolutional neural networks which are extremely good at classification require bucket loads of data. One of the reasons they started to work is that they can be trained on the internet. There's huge amounts of data and compute computation power and lots of interesting little tweaks but the principles of deep networks were there long before their renaissance. But we learn things"
},
{
"end_time": 9466.783,
"index": 348,
"start_time": 9439.258,
"text": " quite quickly. We don't need exposure to everything in order to learn new concepts and things like that. So we're doing it slightly differently. One of the things that humans and animals do when they learn is they select what data to learn from. You pay attention to different things. You forage for data. And so this opens a possibility. Can we define, can we design more efficient machine learning algorithms that gain efficiency"
},
{
"end_time": 9495.145,
"index": 349,
"start_time": 9467.176,
"text": " through selecting the data that they learn from. And then how do they know what data to look for? Well, that's a problem we can investigate in terms of what humans do. Is that related to the frame problem? No, not particularly. It's more, I mean, that's really a problem about how things come to have meaning or a simple grounding frame. Well, yeah, I guess that's sort of related. In the sense that this is really a much more much more kind of"
},
{
"end_time": 9522.432,
"index": 350,
"start_time": 9495.93,
"text": " Yeah, they're related in the sense that basically how much do you need to know about context and things to learn stuff. But just very pragmatically, what's the size of data set that you need in order to achieve certain performance and generalization capacity in a network? So that's one way. But the other way I think is more interesting from a perspective of what we've been talking about, which is do any of these classes of architecture in AI"
},
{
"end_time": 9549.258,
"index": 351,
"start_time": 9523.899,
"text": " Do they serve as useful ways to understand what the brain is actually doing, how it might be actually implementing or approximating something like Bayesian inference? And we'll finish just with a sort of simple line of thinking here, which is the still currently off the shelf networks that people are still excited about are basically feed forward networks."
},
{
"end_time": 9577.671,
"index": 352,
"start_time": 9549.838,
"text": " These deep convolutional neural networks like AlexNet, CatNet, they're feedforward. There are many layers and they're trained on a lot of data, but they process it in this kind of feedforward direction. Seems the brain doesn't work like that at all. In fact, the whole frameworks that we've been discussing are more about top-down predictions being reined in by sensory data. They put a lot of emphasis on the recurrent top-down, inside-out connectivity."
},
{
"end_time": 9607.79,
"index": 353,
"start_time": 9578.234,
"text": " And so to model that kind of activity, a feed-forward deep convolutional neural net is not sufficient. So we need to look at architectures that have top-down connectivity, that have generative models. And there are architectures like this? There are architectures. There are. And there are generative networks now. I mean, there's a long history of generative networks. They go back to the variational autoencoders and things like that. Helmholtz machines. Helmholtz being the same guy that is historically associated with"
},
{
"end_time": 9637.961,
"index": 354,
"start_time": 9608.575,
"text": " predictive perception and the Bayesian brain. But they became a little bit less less worked on because deep networks became so powerful so quickly. But now there's a lot of movement back towards the power of of unsupervised learning of generative models in networks, generative adversarial networks of one example of that, where one network will try and produce examples to fool another network's classification"
},
{
"end_time": 9667.892,
"index": 355,
"start_time": 9638.558,
"text": " You said that Yoshua talks about that as a good model for dreams. Indeed, it might be. There are many other ways to think about what dreams might be doing is just sort of pruning the complexity of a generative model. You let it free run and then you kind of prune its parameter space down a bit. And so there are lots of, I think, lots of interesting things to be explained about perception, cognition and consciousness through coming up with the right kind of"
},
{
"end_time": 9694.019,
"index": 356,
"start_time": 9668.695,
"text": " of machine learning architecture, computational model, and things that involve explicitly generative components that for me that's where the action is at the moment. Professor, thank you so much. I'm definitely going to be following your work and many of the people who are listening are going to follow your work from now. Where can people find out more about you? What are you working on next? Well, thank you. Firstly, thank you, Kurt. That was a very stimulating conversation. We could"
},
{
"end_time": 9723.729,
"index": 357,
"start_time": 9694.275,
"text": " Go on for longer, but I'm about to die, so I don't think we can. But thank you for a wonderful conversation. Thank you. If people are not already completely sick of stuff that I have to say, then you can find out more. Easiest thing is on my web page, which is www.annilseth.com. I'll leave a link in the description. And I think, as you mentioned at the top, there's, you know, there's a 17 minute version of all this is the TED talk, which is out there."
},
{
"end_time": 9750.35,
"index": 358,
"start_time": 9723.951,
"text": " and I am putting the finishing touches to a book aimed at the informed general audience, so hopefully the kind of people that would be watching this, listening to this. The book is called Being You, a New Science of Consciousness and it's all being well will be out sometime between May and September next year. We haven't got a precise publication date but it's"
},
{
"end_time": 9776.852,
"index": 359,
"start_time": 9751.015,
"text": " The plan is to publish it in the middle of 2021, so in less than a year. And you can sign up on my website for updates about that book, if that's something you're interested in. Okay, everyone, go to his website, sign up, get notified when he comes out with this book. Follow him on, do you have Twitter? I do. Oh, yeah. Yeah, that's so you can follow me on Twitter. You will put the link in, but it's just at annual case. But yeah, you can follow me on Twitter too."
},
{
"end_time": 9803.49,
"index": 360,
"start_time": 9777.415,
"text": " Thank you again. By the way, how is it that you stay so fit? Do you have a regimen? Do you meditate? Do you fast? Um, I didn't know why, why you think I'm, I'm that well, no, I mean, actually this, you look healthy. One of the, for me, one of the weird things about the pandemic this year, um, is I've not been, well, none of us have been traveling, but actually,"
},
{
"end_time": 9829.94,
"index": 361,
"start_time": 9804.275,
"text": " I've been lucky enough not to not to come down with it so far. And slightly paradoxically, I feel fitter than I have normally done because I've been able to keep a better routine. Just don't have jet lag all the time. And I can build going for a run two or three times a week properly into the routine. So actually doing looking after myself has become a little bit easier in some ways."
},
{
"end_time": 9857.227,
"index": 362,
"start_time": 9830.333,
"text": " I find that academics and people who are more interested in intellectual domains tend to do well during this lockdown because they like to sit and write and not be disturbed. Well, if only it was like that. I mean, the flip side of that is, I mean, this has been a lovely conversation on Zoom, but the number of hours I spent on Zoom, time zones also seem to mean less because I can now just get wrapped into a meeting in California and the"
},
{
"end_time": 9886.442,
"index": 363,
"start_time": 9857.722,
"text": " Right. Night in Australia the next morning. It's like 7 p.m. there right now, or 8 p.m.? It's just coming up. And lastly, you went like this when you said that you don't have COVID. Do you feel strange as someone who, at least I would imagine, you think of yourself as a rational person? And this obviously doesn't do anything. But it feels right and it feels like if you don't do this, something bad may happen. So how does that comport with how you see yourself?"
},
{
"end_time": 9914.923,
"index": 364,
"start_time": 9888.66,
"text": " That's a really interesting question to finish. Yeah, I mean, it's still true. We still have these... I mean, partly it's a social signal, right? I just wanted to do that to... To indicate to the audience. ...to avoid having to say that, fortunately, so far, I have been able to avoid. It's kind of just a gestural shortcut. But still, academic understanding does not trump our lived experience all the time."
},
{
"end_time": 9945.469,
"index": 365,
"start_time": 9916.408,
"text": " I still see colors as really existing in the world, even though I know they are constructions of the brain. So the way we, the way the study of consciousness changes me as a person is that everything changes, but everything stays the same too. It's great. It's a great talk. Thank you so much. Thank you. I look forward to reading your book, professor. Yes, I'm going to do it hopefully on vacation."
},
{
"end_time": 9950.06,
"index": 366,
"start_time": 9945.964,
"text": " Get some rest, man. Thank you."
}
]
}No transcript available.