Feel Better, Live More with Dr Rangan Chatterjee - BITESIZE | How Your Brain Creates Your Conscious Reality | Professor Anil Seth #439

Episode Date: March 29, 2024

Today’s guest asserts that the way we encounter reality is a construction. Our thoughts and perceptions are merely interpretations of external and biological cues. We’re all hallucinating, all the time. It’s just that when we agree on those hallucinations, we call it reality. Feel Better Live More Bitesize is my weekly podcast for your mind, body, and heart. Each week I’ll be featuring inspirational stories and practical tips from some of my former guests. Today’s clip is from episode 366 of the podcast with globally respected neuroscientist Anil Seth - Professor of Cognitive and Computational Science at the University of Sussex. Anil’s theory is that our brains don’t read the world, they write them – all of life is a controlled hallucination. In this clip he explains how our brains create our conscious reality. Thanks to our sponsor https://www.drinkag1.com/livemore Support the podcast and enjoy Ad-Free episodes. Try FREE for 7 days on Apple Podcasts https://apple.co/feelbetterlivemore. For other podcast platforms go to https://fblm.supercast.com. Show notes and the full podcast are available at drchatterjee.com/366 Follow me on instagram.com/drchatterjee Follow me on facebook.com/DrChatterjee Follow me on twitter.com/drchatterjeeuk   DISCLAIMER: The content in the podcast and on this webpage is not intended to constitute or be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your doctor or other qualified health care provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have heard on the podcast or on my website.

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packs to 10. And these packs are perfect for keeping in your backpack, office, or car. If you want to take advantage of this limited time offer, all you have to do is go to drinkag1.com forward slash live more. Welcome to Feel Better Live More Bite Size, your weekly dose of positivity and optimism to get you ready for the weekend. Today's clip is from episode 366 of the podcast with globally respected neuroscientist, Anil Seth. Anil's theory is that our brains don't read the world, they write them. All of life is a controlled hallucination. And in this clip, he explains how our brains create

our conscious reality. This idea that we're living controlled hallucinations, people could hear that, Anil, and go, what are you saying? You're saying that basically life is just a simulation. Is it not real? And I don't think you're quite saying that. I'm not saying that. It's very hard to find the right words to describe these concepts that are coming out of neuroscience and philosophy. No metaphor is perfect. And in this idea of our experience being a controlled hallucination, the control is extremely important. Let's just reflect for a moment on what happens when we open our eyes in the morning. We wake up, we open our eyes, and it seems as though the world

is just out there with all its colors and shapes and smells and so on, and it just pours itself into our minds through the transparent windows of our eyes and our ears and our nose, as if we're just passive recipients of this objective reality. This might be how things seem but it's not how things are the idea and it's not it's not a new idea it goes back in philosophy hundreds of years to emmanuel kant and back to plato in some ways and in psychology and neuroscience at least 100 150 years the idea is the brain doesn't idea is the brain doesn't read out the world. It kind of writes the world. What we experience is the brain's best guess, the brain's prediction of what's out there in the world or in here in the body. There's this essential indirectness between what we experience and what's really there. I think the easiest example for this is color. Color is such an

important part of our daily lives. It imbues our lives with beauty and meaning. But what are colors? We know from physics that there are no colors, so to speak, out there in the world objectively. There's electromagnetic radiation. It goes all the way from radio waves at one end to x-rays and gamma rays at the other. And our eyes, the cells in our eyes only respond to three of these wavelengths, which aren't colored, right? They're just wavelengths of energy. Yet out of those three wavelengths, the brain generates this infinite palette of beautiful color so what we experience when we experience color is simultaneously less than what's really there because it's just sampling this thin slice of reality but it's also more than what's there because out of that thin slice

of reality the brain conjures millions of different colors so So it doesn't make sense to say that, is our perception of color, is it accurate? Well, that's an ill-formed question because color isn't there in the world anyway. Evolution has developed our brains to experience color because it's useful, not because it exists. Yeah. Okay. I love this, right? I absolutely love this. So

a couple of years ago, we were on holiday somewhere, my wife, myself, and my kids. And I remember looking at the sea. And I think one of the key things I want to teach my kids is that everything in life is just perspective, right? And I think this really speaks to your work. It's just perspective, right? And you have a perspective, but other people may have a different perspective. I'm always talking to them about the things they get taught. I say, okay, could there be another explanation for that? What's an alternate viewpoint on that? I think it's a, I'd like to believe it's a really great way to interact with the world, gets us out of our

little tribes where we think that things are only one way. And we looked at the sea and said, what colour is the sea? And because we do this quite a lot, ultimately the conclusion was, well, the conclusion was, well, the sea appears to be blue to us, but we don't know what color a dog sees. Or maybe we do, but to my knowledge, we don't know. What does a dog see when it sees the sea? What does a dolphin see when it sees the sea? Does it see it as pink? Does it see it as green? Does it not even have a color, right? So when you start looking at things like that, is it then accurate to say, not that the sea is blue, I perceive that sea as blue? Yes, I think that's much more correct to say. The artist Cezanne said this years ago too, he said, colour is where the brain and the universe meet. Very nice way to put it.

Beautiful. where the brain and the universe meet. Very nice way to put it. Beautiful. And the color of the sea, the color of anything, is not existing in the thing itself. It's what the philosopher John Locke called,

it's a secondary quality. It requires a mind to exist as well. Not everything is like that, right? Solidity. If you think about a car coming down the road, it's a particular color that color only exists in the interaction of the physical object that's the car and the brain that's looking at it and because we all have different brains you and i might have a slightly different experience we just probably won't realize it but the the car still has solidity

that's not dependent on the brain if you you go and jump in front of it, it's going to do some damage. But the way we experience it, that's always a construction. So I think this is a key part of this idea of controlled hallucination. I'm not saying that nothing exists, the mind just makes up reality. No, reality is there and reality can bite. But the way we encounter reality is always a construction. We never see things as they really are. We see them, I'm drawing another quote here, stealing a quote from the novelist in Aishanin.

We see things not as they are. We see them as we are. But that doesn't mean they're not real. They're perfectly real. And that's why we can get around in the world. We can behave. That's why when people are hallucinating in an uncontrolled way, maybe through psychosis, maybe through chemicals, maybe through other things, they're less able to behave in the world because now their hallucinations lose their grip on reality. Not only do we all see the world differently, we all perceive the

world differently, even within ourself, there's multiple versions of us that can see the same thing in different ways. So an example would be an email, right? I'm not a neuroscientist, so please do give me your perspective on this. But one thing I think a lot about, and I would say for a good two or three years now, is that we all see the world through the state of our nervous system. So you can read an email at 4 p.m. on a Friday if you've had a fraught week and you're tense and your stress is up and you don't feel you've got enough time to finish what you need to before the weekend. So because you're stressed, your whole system has changed. You're no longer having your peripheral

vision. You've now got tunnel focus trying to get things done, right? You can interpret the words in that email as a threat. Whereas, let's say after a relaxing weekend, on a Monday morning, when you're in nice, let's say you're in a calm state, that same email with the same words, you can infer a different meaning. You can perceive it differently. So it's not only we all see the world differently,

there are multiple versions of us within ourselves that can also perceive things differently. That's a really good point. I really like that. And I think it's absolutely true. And I think it speaks to this fundamental subjectivity of how the brain creates experience. So again, we see things as we are and we change.

We change over time. And the example of the email really hits home because I've had exactly that experience. We also have it when we're talking to friends or partners where if we're stressed about something at work, we interpret what somebody says in a very different way than if we're relaxed. Interpret being the key word.

Yeah, the truth is not necessarily in the sounds that we hear. It's in the meaning that we make from them. And what I think is fascinating, it's actually one of the things that I think can help each of us. When we recognize that it's really that way all the way through our experience, even color is an interpretation. It becomes easier to catch yourself in the act of interpreting things. What was the example I think you referred to in your book?

If people were anywhere near the internet in 2015, it would have been very hard to avoid this particular meme. So this was a photo, a badly exposed photo of a dress. And it suddenly tore around social media because there was this violent disagreement. Some people said, well, that dress is clearly white and gold. And then some other people said, what are you talking about? It's clearly a blue and black dress. Absolutely no question. And I looked at it and I thought, well, that's clearly a blue and black dress. And I took it around my lab and the first five people said, it's a blue and black dress the sixth person said it's white and gold and i thought oh hold on it's there is something here and i didn't know what it was at first um but of course i agreed to try and explain it about an hour later and what what's happening

here is that the colors that we perceive depend not only on the light reflected from the thing itself but on the context. So this is another general thing about interpretation. When we interpret something, we interpret in a way that's hugely dependent on the context in which we're in. This could be an emotional context, like you said, the difference between a stressful Friday afternoon and a peaceful Sunday evening. But in the case of the dress, the context was the ambient light, the surrounding light. Our brains do something very clever,

which is basically control for what the ambient light is. This process can vary a little bit between people. And this particular photo of a dress hit a sweet spot where for some people, their brains assumed that the ambient light was relatively yellowish, that it was an indoor scene, in which case their brains inferred that the dress was blue and black.

But for other people, their brains assumed that the ambient light was more bluish, like an outdoor light, and their brains inferred that the dress was white and gold. What was just fascinating about the dress is that it really perplexed people because it challenged this assumption that most of us have most of the time that we see things as they are. And we have this common phrase, like, I'll believe it when I see it.

And by just this one simple example showing that, hold on, it's the same image, yet two people can have a radically different experience of the same thing, usefully undercuts that idea. Well, what you're speaking to here through this example of a dress, it's like, wait a minute, you see the world the way you see it, right? Not everyone sees it the same way. All we're ever seeing is our own perception. Just as we all differ on the outside in terms of skin colour and height and body shape and so on, we all differ on the inside too. And knowing this, I think, is vitally important. It's an important scientific challenge. Let's see what's out there.

this i think is vitally important it's an important scientific challenge let's see what's out there it's a bit of a voyage of discovery but it's also i think socially important for exactly the reason you were hinting at that one of the things that the dress episode suggested to me was the importance in general for people recognizing that they have a point of view. That's what we see when we see the dress light. It's not as it is. I'm seeing it through my point of view. And recognizing that we actually have a point of view is important. One of the examples I have used in the past to try and explain this to people, I have used in the past to try and explain this to people, not from a neuroscientific point of view, but just from the idea of trying to understand, well, what is truth? What actually is going on? And the example I often use is, let's imagine there's a romantic couple, okay? For ease of explaining, let's call it husband and wife, right? Husband and wife are having

a heated disagreement around the kitchen table. What was the truth of what happened? Well, I think the truth of what happened kind of depends on who you ask. Like the husband will have their perspective on what just happened in that five or ten minute heated disagreement. But if you walk around to the other side of the table, the partner, the wife, let's say, may have a completely different perspective on the same situation. So actually, what was the truth? What actually happened? Well, it kind of depends on which side of the table you're sitting on. I think that's quite helpful for people to really understand perspective. Yep. I mean, so what does this speak to?

So I think there's two things. Firstly, it's important to recognize that something did happen. Maybe a glass broke in the kitchen and so something happened. But beyond that ground truth, then things can start to differ in very dramatic ways through the biases that we have and i think the really important thing here is that it's very hard sometimes to know that we have these biases that we have these interpretive processes that are creating the world for us we see them. We don't realize that we have them. So I think it's very helpful to the extent we can recognize that all our perceptions are our creations, our constructions, but not totally arbitrary ones. That helps us put a higher level of context on top of it. We can get a bit of distance. Is this where practices like meditation

and mindfulness can be so helpful? Is this one of the reasons why they can be so helpful? Because it helps us develop that distance, that psychological distance. It helps us realize that we can observe these multiple interpretations. You know, given how long you've spent studying the brain and consciousness, how do you see meditation and mindfulness and their potential benefits? Extremely complimentary. I have been on a couple of retreats and I'm very interested in it. And I've some experience and I've talked to a lot of people who've meditated a lot.

And I think the parallel, the complementarity does lie in opening this little gap, this very useful gap between how things seem and how they are. In meditation, one of the standard ways to engage in meditation is just to let your thoughts, experiences, emotions, moods just pass by like clouds breezing across the sky. To just witness their passing and not buy into them in the way that we often do. We have a thought and it leads to another thought and another thought and we start ruminating. Meditation just makes you realize that thoughts are just thoughts. Thoughts come and they go.

Our perceptual experiences, they come and they go. They pass. And they are, I think, deeper into meditation. You also get some recognition that our thoughts, our emotions, because emotions are just forms of perception too. They're just the way the brain makes sense of what's happening in the body. All of these things are constructions, creative acts. I know a former guest of yours, Ruben talked about this in these kinds of words that everything that makes us human

is a kind of creative act. It's not a passive registration of just something that's there. And meditation can make that pretty clear as well. We train our attention so that we don't get wrapped up in these habits of thinking, habits of perceiving, habits of behaving, but can step outside of these habits just for a little while.

And if you do that enough, then I think you can recognize the grip they have on you in your everyday life too. So studying neuroscience for this long, I don't think it's equivalent to spending 10,000 hours in a Himalayan cave somewhere really meditating. But I think the place you get to is somewhat similar. Another aspect of meditative practice is to realize that the experience of self is also changing the self is not this fixed thing but it's a bundle of different kinds of experiences and perceptions and that's very very complementary to to the to the perspective that i'm trying to talk about here too the beautiful phrase that you use in the TED talk, and I think in the book,

we don't passively perceive the world, we actively generate it. I mean, that is thought-provoking, that we are actively generating our experience of the world. And if we're all creating our own experiences of the world, you could go to a stream and go, we're all just playing our own internal computer game, right? So what does it mean for us? Like, how do we put all of this together, Anil, and try and then interact with the world? I think it's by recognizing that, yes, our perceptual experiences of the world are individual, are distinctive.

What we can take from it then is that indeed, we each create our own experience in an individually distinctive way. We have different brains, we have different bodies. We will inhabit a unique subjective world. But that it isn't arbitrary. There is a real world. Evolution has designed our brains to make pretty damn sure that most of the time we see the world in ways that it's useful

for our survival, for our behavior, for our daily activities. So there's always this balance. What we don't want to do is fall into a kind of solipsism or something and say, like, the way I see things has got nothing to do with the into a kind of solipsism or something and say like the way I see things has got nothing to do with the way anybody else sees things no we there there's a lot of overlap but recognizing that we have a perspective that we have a point of view that there is this indirectness and that this applies not only to the world, but to the self too. I think that's a very useful message to constantly just,

I mean, what I do often, I don't know if this is generally helpful for people, but to try and automate that a bit. So when I just walk around the world, it's a bit like a kind of walking meditation in some ways. I will just occasionally stop and just reflect on this for a bit. Just think about the colors that I'm seeing and just think about where are these colors? Are they out there?

They seem to be out there, but where are they? They're in the interaction between the world and my brain. And recognizing that, I think, really can be very helpful. It really does introduce this space between how things seem and how they are in a way that allows us to to better communicate with others because we can recognize that they have their own kind of creative act of perception too yeah hope you enjoyed that bite-sized clip i hope you have a wonderful weekend and I'll be back next week with my long-form conversational Wednesday and the latest episode of Bite Science next Friday.