#146 The Most Complicated Thing in the Universe: What is the Brain?

28:40Matthew Cobb:it was it actually meant that now i had a framing not only for what i'd i now had to go back and rewrite but also for where i was going to go in the future and i thought okay that that's interesting that makes sense and it also makes it really exciting because then you think and scientists do this because they don't think about what they you know they use these words code and information they don't worry about where it comes from it all seems natural to them and if you say look this is bound to the technology of the time you know different from descartes thinking about hydraulics they go so you mean this might change in the future with new technology and you go yes of course.

29:17Matthew Cobb:And they go, that's amazing. So what is it? My answer has always been, well, if I knew what the future technology is, I'd be very rich. I have no idea. But we can just see that thinking is linked to the conceptions of machines in particular and power and forces. And that will change in the future. Okay, family. Thanks for dinner. I should get going now. Not without Dessert. Done. Just ordered on DoorDash. I keep eating cake, but tomorrow's Juan's graduation. Well, that deserves a toast. Let me get some drinks.

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30:38Yeah, I think this is extremely interesting. Like I've heard that some people had compared, you know, the brain to like an intricate kind of harp or something, whatever sort of complex, whatever the most complex thing they could think of, the brain must be a little bit like that. And that should give us perhaps some pause in thinking like, okay, maybe saying the brain is like a computer or an AI system is kind of accurate in some ways, but we should remember that this is a metaphor. and we'll get on to this but like i mean it's worth remembering that metaphors are not saying it's the same thing as you know and and that's the mistake that has so often been repeated and the only mistake that's repeated more than that is thinking that we are now somehow not making a mistake um but okay so i because i i want to talk about sort of once we've established that the the brain is is the key sort of part of thought i want to talk about some of these more recent developments but i kind of just want to ask like just to fill in this picture of exactly how we got there like it can't have just been galen doesn't experiment in the ancient world and then it takes 2000 like years for people to finally accept it must have been other stuff going on or was it really just a case of like i guess it was like the discovery you said like anatomy but like the discovery of nerves people noticed that they were up to the brain and i suppose the also the discovery that the heart is just kind of a pump this kind of stuff just just slowly grew a consensus that the brain is what matters here yeah and you said it was around about when that people finally were sort of on board um in the middle of the 18th century right and that coincides with the next big

32:17Matthew Cobb:breakthrough in thinking about how how the universe works but also how movement occurs and that's the discovery of the electricity yes and very soon people were able to uh produce show that electric shocks initially was the initial way they do it would produce movement yeah and you could do this uh for example with a frog's muscle uh and they generate electricity by um this initially would be static electricity so you you get some a bit like you you know when you're a kid and you're your dad or now if you're dad you get a balloon and you rub it on your jumper and it sticks on the wall yeah static electricity so you can produce a charge uh by rubbing wool against amber for example and there were people who were called electricians who would have this as a party piece and they go around uh and you go in and you'd get a for example there was a there was a show called the electrified boy where you get a hapless child and you'd winch them up to the ceiling uh and then And you'd electrify them with the static electricity.

33:24And then you'd throw a load of feathers in the air. And of course, all the feathers would stick on the poor child. So you could do things like this. Which, again, would have been extraordinary to see. Yeah, absolutely. But when this is new, when this is hot off the press. Incredible, incredible thing.

33:38Matthew Cobb:It was very eerie. Interestingly, people also started to use it as an early form of therapy. So there were itinerant electricians who go around the country and give you an electric shock. So they charge this thing up and then you really high charge and then you touch it and you get an electric shock and it might or might not help cure your mental health problems. So, for example, Marat, the French revolutionary, before he went on to lead the French Revolution in 1789, he was touring the United Kingdom, giving people electric shocks because he was a great believer in the power of this. So there was a link between movement, perhaps something to do with mental health that was kind of unclear, but the whole series of reports of how this might work that led people to think it wasn't just nonsense.

34:31And we're still not clear about the power of this kind of therapy, which was developed substantially in the 20th century and is making a bit of a comeback today. the key development however came with the development of uh what we call in english batteries and this was uh to try and resolve an argument that was taking place as to whether there was electricity in an animal uh or whether it was simply responding to it because even if you're getting this response you know you you put a uh you generate an electric current and you touch a muscle with it if it contracts well okay but it'll do the same if you put a drop of acid on it so it might be an irritant so people were thinking very hard and you know if they weren't happy with

35:15Matthew Cobb:the idea they try and find other explanations uh and with the development of the batteries which were developed as a bit of biomimicry so uh volta who's where we get the word vault from he was trying to uh develop something they studied electric electric fish so fish that will give you a shock if you touch them and he know they knew the organ that produced the electric shock and it had these kind of layers in it. And he decided to try and imitate this. And so he makes layers of using cardboard and metal and acid, and he produces a pile of these things. And this, in the end, would produce an electric current.

35:53Now, we in English call this a battery, but in every other language, it's called, for example, in French, it's called impile. It's still called a pile. The only time we still talk about piles in this sense is talking about atomic power,

36:07Matthew Cobb:where we call it an atomic pile but that's because the guy who first developed it was italian so he was basically we should we call it an atomic battery but it goes back to this side it's a piece of biomimicry as i say interesting okay and in the beginning of the 19th century you can now store electricity and you could do dramatic things like one uh one philosopher got uh uh he got about 300 monks and got them all to hold hands so you got about 600 meters worth of monk and he goes to one end and he connects them to this battery which just releases uh the power and they the electricity the current goes down and they all jump up one after another another um and then you could do things for example uh i mean in people would do you could go to the london stage yeah and see shows in which people would bring on a cow's head poor cow had just been slaughtered backstage they'd bring on the cow's head and then put its electrodes on either side of its ears or whatever and its eyes would open its tongue would roll yeah i mean that's terrifying right and that would have like the royal institution is that what they used to do well they this was this would be done as just for fun at a as theater so you could go to the Drury Lane and watch it.

37:27Matthew Cobb:And there was a notorious private demonstration of this in London where 12 members of the Royal Society went in. A man who'd killed his wife and child was hanged. And then they immediately took his body down and put it in a room with these members of the Royal Society and they did the same thing. And of course, you know, you put electrodes on a body and its eyes are going to open and so there's a famous engraving of all these scientists fleeing because this the scenes like the eyes would open yeah absolutely and arms would move really you know so what we know so some listeners may be thinking hang on a minute this sounds very familiar uh in in about 1815 so all this was done at the beginning of the uh the 19th century in 1815 a young woman called she was a teenager called mary godwin she went to the royal institution you just mentioned, which is this newly created center for scientific communication, which still exists, a marvelous institution.

38:30And she saw some, or we think she saw, some similar demonstrations to the ones I described with the sheep's heads and all the rest of it. No humans were involved. And there were only a couple of experiments like that because it was quite rightly seen as pretty foul. And so she saw this idea that you could actually resurrect, apparently resurrect life using electricity. And then two or three years later, she'd run off with a notorious poet and revolutionary Shelley. She had become Mary Shelley.

39:00Matthew Cobb:And on their honeymoon, because there was a volcano in Indonesia, the weather was awful. So the world's weather patterns changed. They were on holiday in Switzerland. It's raining all the time. So they sit around and they say, let's write ghost stories. And Mary Shelley writes Frankenstein on the basis of this idea of you can actually reanimate life by sticking bits together. Incredible. It's incredible. I love those little historical footnotes more than like anything. It's that and etymology that come out on this podcast that are my favorite things in the world. But when you talk about electricity, people might be thinking, I mean, I find it very difficult to remember that when we're talking about electricity as it was discovered, we're not talking about exactly like the kind of stuff that you find in like an iphone or an ipad or something it's it's it's hard to sort of explain exactly what's going on there but what what what do we mean by electricity when we're talking about like the brain or organisms and how it's affecting like what is this thing called electricity well i mean electricity in a in a wire you've got a solid wire and the current is the movement of electrons down that path, down from one end to another, because there's a difference in potential, so it's going to go from one end to the other.

40:19In neurons, and this took an awful long time to find out, and it was only really resolved after the Second World War in the 1950s, you've got, it's electrochemicals. We've got chemicals in our neurons, in all our cells, and you get a difference in the same principle, You get a difference in the potential on either side of the membrane, either the surface of the cell.

40:42Matthew Cobb:And our cells have got little, little pores in them. And when a neuron is activated, then there's this wave of changes, this movement of ions of different chemicals in and out of the neuron. And that passes down in the same kind of way. So it's an electrochemical. But I mean, you know, you can, if you, as I've just described, if you use an electric electrode, it makes that happen. So effectively, it's the same thing. It's just that it's fluid and moving rather than, it's an atomic level, of course, rather than like a tap. It's not like that. But this movement of ions, different charge forms of atoms in and out of our cells, every second, every millisecond, or what I'm doing now, that involves really, really complicated activities of all those neurons.

41:35Yeah, so a similar kind of process because electricity just being like loose electrons, electron, electricity, and then those electrons just sort of move down a wire and that's the thing that's moving down. It's something kind of similar going on in the brain. Okay, so there's the discovery of electricity, of its existence, then there's the discovery that it seems to affect organisms. And then you said, well, some people thought maybe this was just a reaction. then presumably at some point we managed to establish that no no like that's what's actually happening in the brain when does that happen how does that happen and like why is that important

42:14Matthew Cobb:well it's it it happens partly by again by metaphor right in that uh people drew maps of the nervous system and by this stage by about 1838 the telegraph had been invented so you can send messages. And you have a map of the telegraph system of England, for example, and you've got the centre, sadly, is London. And then emanating from it or going to it are all these literal wires that messages are being sent down. And two things are happening. One, the centre is telling the provinces what to do, but it's also receiving information. This word started to be used. receiving signals from the provinces saying what is going on.

43:01So people actually literally drew a parallel and said, this is actually what is happening in the brain. Our brain is some complicated kind of telegraph system. So it made a big leap, just as technology had, the transformation of the United Kingdom, of the whole of Europe, and then the United States, with the development of the railways, which literally paralleled the telegraph system. and they went down the side. That technological development was then used to try and understand what was going on in the brain. The brain must be doing something similar. So people start to think about telegraphing and so on.

43:38And one particular chap who I discovered in writing the book, who I hadn't heard of and very few people apart from a handful of historians of 19th century you'd know about, a chap called Arthur Smee, he came up with the idea that this was literally what was happening in the brain. The brain worked like a telegraph system, and therefore I can make a version of that. I can actually construct it. I can actually construct

44:05Matthew Cobb:something out of metal that will represent a concept. And he came up with an idea for the way that information or the way that signals from very simple inputs from sensory perception could then be combined. And this is all very vague. But when I show those, if you show those diagrams to somebody who works on large language models, they get really excited because they say, look, that's just the kind of thing we draw to try and show how ChatGPT can actually, you know, respond to us in the way it does. It's all these complicated cross-cutting combinations. um now smee smee's device is very hard to make sense of and he never built anything he wasn't trying to build a computer right he's building a brain out of brass and screws uh and he hasn't although he is thinking about electricity and he even thinks he vents the fax machine actually because he says look if what's going on in the brain is we got an eye and there are photoelectric cells there are cells that are turning light into electricity and that's going down the wire into the brain we could do that technologically we could get some kind of device that would turn light into electricity we could point it at you know a picture of the towers tower of london and then send it down the wire to edinburgh whatever yeah now he never built it but i mean he was he was very he was a he was he was a completely cranky inventor he also ended up working on inks and electrodes, which were later used in experiments to understand the brain.

45:43But the key point is that this metaphor of the telegraph system is really taken to heart by thinkers because they can now find a very powerful metaphor, not just for the organization of the nervous system, but for what is going up and down them, its messages, its information.

46:02Matthew Cobb:And that immediately makes an intuitive sense. LinkedIn is pretty great at a lot of things Like helping you tap into the latest trends and insights in your field We cannot stop your co-worker from tapping her pencil LinkedIn can help you find new jobs that align with your career goals We cannot help you find the source of that weird smell in the office fridge And while we can't stop your co-workers from bringing their hobbies into the office LinkedIn can help you bring your career to the next level LinkedIn is the network that works for you I'm R.J. Decker, a private investigator uncovering the sunshine state's darkest secrets.

46:43Tuesdays, it's the premiere of ABC's hottest new crime show. R.J. freaking Decker as I live and breathe. He's a private eye. It's not a standard murder. It's someone bigger. And a public mess. Trying to get sent back to prison today? You go to prison one time and suddenly it's all the jokes. R.J. Decker, series premiere, Tuesdays on ABC and stream on Hulu. yeah okay so we've sort of arrived at this this realization that the brain is kind of working electrically sending a kind of signal or information and that it's definitely the brain that's that's doing it so then the next question that someone might have in trying to uncover the mystery of of how we think is like well okay we've got all kinds of thoughts all kinds of all kinds of different stuff going on we've got got memories we've got emotions we've got like behaviors that we do we've got this one big brain that sort of does it all but there's also this growing understanding that the brain is quite a complicated organ and of course the debate becomes well is there just this one great big brain doing everything or is the brain like a sort of divvied up you know civil service of of people with their own little telegrams to send out to different parts of the body.

48:04Matthew Cobb:Well, if you really took it to its end point, that's what the kind of informational 19th century Dickensian bureau system of thinking about thinking and the brain would lead you to. And that is kind of where people ended up, but it depended what nationality you were. So one thing that was very, very popular throughout the 19th century, even to the 20th century was what's called phrenology. That is that you can, the idea that you can feel the shape of your skull, that will tell you something about your personality. Because the theory went, the shape of the skull revealed the shape of these structures in the brain.

48:48And those structures in the brain were kind of the localization of different functions. This is the term that scientists and historians have used to kind of describe this debate, the localization of function. is this bit of the brain doing a particular thing and this was incredibly popular uh i mean you can think of a bit a bit like horoscopes today i mean people might still say well i'm aquarist rising whatever okay what are you and you know uh without taking it too seriously um but queen victoria took it very seriously yes she had her children phrenologized karl marx the german revolutionary he took it very seriously uh he would feel somebody's head a new comrade to see are they trustworthy?

49:28Are they on the right line? And I recently discovered, I've just finished a biography, a variety of biography of Francis Crick. When he was a child, Francis Crick was phrenologized by a traveling phrenologer who amazingly said, yes, your son's, said to his mother, your son's head is really interesting. You know, maybe I should come back again and do it again. So this is clearly nonsense, right? Because, you know, your skull's really thick and all the blumps on it do not correspond to organs in the brain. But it was very, very popular. And what it led to was kind of a pushback from, in particular, the scientists.

50:05They said, well, this is garbage. And the French scientists in particular, for two reasons.

50:09Matthew Cobb:Firstly, they said, well, if we look at the brain, it's divided in two, and those two halves are mirrored. So it's kind of perfect in that sense, because you've got two identical halves. Secondly, Descartes said that thought is unitary. Thought is one thing. Therefore, the brain cannot be composed of lots of different bits. And this is nonsense, but this is the kind of argument. And a poor chap called Broca, who was very Cartesian, that is a follower of Descartes, good Frenchman, he ended up against his will. Actually, what he went through is, many scientists have found this, You got a view, and then the data push you somewhere you don't want to be.

50:55Matthew Cobb:And the experiments you do and everything you do to try and prove these findings wrong, it go in the other way, and you end up trapped. It's a horrible feeling, but it's also quite exciting. So Descartes, Broca was convinced that there was no localization of function. But he was working in a Parisian hospital, and he noticed that there were, he had patients who had strokes and who therefore lost the power of speech, or their speech was severely reduced. And he then started dissecting their brains. And he found that whenever one of his patients had lost the ability to speak, then there would be damaged lesions in the front left part of the brain.

51:35And his eventual conclusion was there is localization of function, that speech is controlled by the front left part parts of the brain, which we now call Brocker's area. This is the production of speech. So back to Gayle, it's quite interesting. It's the same thing. And poor old Brocker is in a double bind, firstly, because he's just shown that Descartes was wrong. He can't have that. Secondly, Descartes's doubly wrong, because now the brain is not symmetrical. You can't tell by looking at it with the techniques they had at the time. But this part of the brain is doing something different from this part.

52:12This part does not control, your front right part of your brain does not control speech. It's this part here. So now it's getting very exciting. It seems that there is localization of function. Some functions are very specifically in particular places. Yes, which would have in some way supported the phrenologist's idea, right? Absolutely.

52:31Matthew Cobb:Except they never had speech here. It would always be things like love or, you know, it's all about emotions or intelligence. All good things were distributed in your brain yeah yeah yeah yeah i mean you're right that i mean it's amazing how popular the viewers but you say that um charles dickens is one person who may not have been impressed impressed with this because in great expectations uh the criminal mag which explains that he was subject to a frenology how would you say that frenological examination before providing a simpler explanation of his behavior he says they measured my head they had better measured my stomach yeah which is you know probably true i mean we do now know that like you know judges are more likely to send someone to jail if they if they're hungry for example which is quite an investing phenomenon but but but okay so we now it's a weird hodgepodge isn't it because it's like okay so people some people thought that the brain was responsible for like different parts of the brain were responsible for different stuff and they therefore maybe reasonably thought they could probably feel it through the skull and it's like well they were more right than they could have known about the the sort of the different brain regions being responsible for different things but that other part about the skull anatomy is like is like total nonsense and it's amazing how sort of sometimes on the nose and sometimes not although the extent to which the brain is a unified entity versus a sort of specialized system of individual part is still quite like hotly contested oh yeah very much so i mean i don't part of the problem is scientists in particular those who study in particular area will tend to uh kind of have a very condensed short version you know kind of elevator pitch to explain things to public so this part of the brain controls this or this and the answer i mean so that's localization of function and really you're back with this series of organs just like in phrenology nobody really thinks that or very few people think that.

54:25I mean, scientists, neuroscientists do, but it's the kind of shorthand they would use. But I think the public does end up with this idea that we've got, you know, these bits of my brain and, oh, we've got a left brain and right brain. We can talk about that later on. And, you know, I'm a left brain person. I'm a right brain person. And whilst

54:40Matthew Cobb:there are asymmetries, like in speech, I mean, the brain is both unified and distributed and consciousness and all the various other perceptual things that we know about are both localized and distributed. And the localization, certainly animal studies, show us that the localization of memories or whatever, or perceptions, and this is where it gets really weird, you can identify a set of, for example, if you teach an animal that a particular part of the cage with a particular shape on it is somewhere they're going to get food, then they learn, you've got a representation of, say, the set of stripes that are on the wall.

55:26And you can record from cells that show that they fire every time it sees these stripes. If you carry on recording from those cells over the next month, then some of them, a large proportion, will stop firing. Because, in fact the scientists call this representational drift so you've got a representation but it's

55:47Matthew Cobb:moving inside in time so a different set of neurons are now doing the same thing so the same task is sort of just like moved in the brain that there'll be some that are still involved but my guess is that if you left it long enough then a whole different i mean you know this is we're in a very small scale it's probably still the same region yeah doing it um it's just but I can imagine like the scientists who first discovers this finally thinking they're beginning to nail down localization and then they're watching it move and they're like, hmm, yeah, not so sure about that. Yeah. So this representational drift is a very neat kind of phrase, but in fact, it's just kind of these, oh my God.

56:25Matthew Cobb:But I mean, maybe back in the, let's move back to the 19th century because this is when they start to record. They do two things. They record from electrodes invented by Arthur Smee, very fine electrodes using batteries that he's developed as well. that mean that you can record from different regions, say of a monkey's brain. And you talk about animal experimentation. Interestingly enough, it was a public outcry against some of these claimed activity of some of these experimenters that led to the UK's introduction of very stringent restrictions on what you can do with animals and experiments. So yeah, absolutely.

57:07So there's always, this has been a long, long argument. Many countries don't care so much, but you've got to remember in the UK, we have a Royal Society for the Prevention of Cruelty to Animals. Quite right. But we do not have a Royal Society. We have a National Society for the Prevention of Cruelty to Children. The RSPCA was founded in the 1830s.

57:30Matthew Cobb:The NSPCC was founded in the 1870s. So you're happy to shove children up chimneys, but not to do bad things to animals. Yeah. So, I mean, that just shows you the British attitudes. But, I mean, I think most scientists work in the UK are very happy with our very strict controls there on animal experimentation. Anyway, the key point is that you could record from or stimulate different parts of the brain, put electrodes in, and you would stimulate the monkey's brain, and you would be able to show that different parts of the brain were involved, say, in producing movement, or in apparently producing the perception of sound so the monkey's ear if you put areas in one particular electrodes in one particular area then the monkey's ear would twitch and there's also a very famous accident that happened uh where a i've completely forgotten his name that's okay we'll take a minute it doesn't matter we can leave it in well what's his name um everybody knows his name who are you talking about the guy who gets the uh the b oh um um i didn't write this down you see uh no i've got this i've got this uh and if i don't say i mean it's it's in the book i've got this it's it's there's a p in there is there a p in there see this is interesting about when you're trying to remember things it shows you how things are encoded right do you know what it's so you know you can see the shape of the word or you know it's got a p in it and that shows you that the thing or the name that you're trying to remember is tagged with all sorts of different bits to it which you use for retrieving it it's there and there's somewhere i think about this all the time i'm like um one of my favorite things to do when i'm like reflect it's it's it's less about brain science and more about um it's almost like meditation where i say to people like you know the tv show friends like you could name all of the five characters from friends right and i'm like don't don't actually focus on don't do it right now you know that you could and yet those names are not actually like present in your head so that they're like there but they're not there until you like focus your attention over there you shine the spotlight on that part of the brain it's also interesting how like um And it's that classic thing where if I asked you to name every book you'd ever read, you'd probably get to about 10 and then start forgetting, right?

59:52But if I went the other way, if I listed off every single book that you've read, you could tell me instantly whether you'd read it or not. It's like memory kind of works in one way, but not the other. But yeah, there's a guy who got a pole through his head.

1:00:09Matthew Cobb:It was a big tamping rod. So he's working on a railway cutting and you drill a hole and you put the charge in and you put the tamp it in and then you fire in the hole and you run like hell. But anyway, it went off and this tamping rod goes right through his... Don't tell me. Don't tell me. Don't tell me. I'm going to remember. I'm going to remember. I think this is great. It's got an experiment in real life. It's perfect. um well of course of course you know fans of the show will know that i talked about this with robert sapolsky so if you don't know either at home then you obviously haven't been paying close attention either um but yeah so he's working on the railway and this pole sort of gets like ejected and just like goes straight through his head in a way that if you looked at it you'd probably think it killed him his skull his skeleton is still on display in american medical school and it does look like you could never recover from that and he did recover and this is where it gets murky so if you read neuroscience books classic book they say uh you know he he was he was no longer a gauge phineas gauge phineas gauge we got there how about that thank god yeah that's incredible yeah it's like something lit up it's like it's so hard to explain but yeah i i got there by thinking because the phrase was gage was not gage that's what was written down and so i knew then i was thinking about that and i got to gage and you got the phineas and the rest which has got a p but it doesn't sound like it yeah exactly when alex popped his head over and he went to start telling me and he went and i went don't tell me and i'm thinking fred phineas phineas gage yeah so uh the classic story will tell you that phineas gage gage was not gage his personality was changed.

1:01:52Matthew Cobb:He became from being affable and pleasant. He became surly. He became changes in his personality. In fact, all this is very difficult to prove. And there's no evidence of this at the time. It's all kind of retrospective. What is clear is that he did go on to, he ended up, he made a fairly complete recovery. He became a stagecoach driver in Chile. I can't remember all the details. But the idea was, and this corresponded with some of the animal experimentation, that there's, in terms of your will and your confidence and your control over your emotions, that the front part of the brain is extremely important.

1:02:30Matthew Cobb:So we're back to the localization idea. I mean, in terms of getting over the idea of localization, then I think the speech is the best one because this is uh historically it's the first it is very clear you can do it you can see i wouldn't do this but you can see experiments on youtube where people get big electromagnets and they're in in a scientific situation and they're speaking away and they put this electromagnet and that magnet here and they can't speak anyway take it away and they're fine they sort of send i don't know what it is they're actually sending it's just electromagnetic it's just very strong magnetic field and you're talking about literally like as you're speaking now yeah absolutely place this device yeah and they would start just being unable to speak it's just slurs and you can't just basically you're this strong uh electromagnetic field is just screwing up all your neurons i mean it's temporary i still wouldn't do it yeah yeah i'd love to try that because presumably the person who's speaking is still cognizant of like what they're trying to say yeah but it just doesn't come it just like doesn't work i suppose it'd probably be comparable to like being paralyzed or something where like yeah absolutely trying to move your arm and it just it just sort of doesn't doesn't go yeah or maybe it's what people feel when they have a stroke you know yeah so yeah viewers if you know you feel your face somebody's face slips and they start slurring their speech then that two are very important signs of one particular kind of stroke make sure you get to a physician unless they have a scientist putting a big sort of electric then i think we can exclude that then you might be okay So the interesting thing is that is really solid information, localization of speech.

1:04:09Yep.

1:04:10Matthew Cobb:And then after I wrote the book, about two, three years ago, paper appeared, which was co-produced, as they put it, between some scientists who were doing MRI scans and a woman who was in her 30s. This was in America. She was a secretary. She'd had a college degree and everything. and she wrote to them and said, they put an advert saying, we want to scan people's brains. And she said, I think you might want to scan my brain because people have told me it's quite interesting. So I said, okay, fine, come in. She sat in the scanner and they look at her brain and the whole left-hand side of her brain is just black, it's just empty.

1:04:48Matthew Cobb:There is nothing there at all. She only has the right-hand side of her brain. As in like physically it's not there. Physically it is absent. There's a big hole. I mean, it's a big hole. You know, it's a big fluid-filled hole in her brain. Right. But as in, so sorry, but like as in there was like a brain there and it was just, it had like a chasm in it? Yeah, well, her skull's still there, but it's just if you were to... But the brain matter itself. The actual matter was just completely absent. Wow. So, I mean, she knew this because, I mean, when she was a child, what they think happened was that before she was born, she had a stroke.

1:05:24Matthew Cobb:So already when she was in the uterus, she had a stroke and the whole side of that left-hand side of the brain did not develop. Now, what's interesting is that she's perfectly normal. You would not know if she hadn't at one point in her life had a scan. She would not know there was anything the matter with her. There isn't anything the matter functionally. So what's happened is the right side of the brain, what scientists call plasticity. That is the same, you know, different brain functions can emerge in different areas. So what that tells us is although the ability to speak is clearly determined by this structure in normally developed adults, in children and in if you've been damaged at that stage, then you can actually overcome that.

1:06:13There are some cases of adults as well who've had very severe strokes, nevertheless recovering virtually complete function. We don't quite understand how that happens beyond saying, well, it's plasticity.

1:06:23Matthew Cobb:That's pretty rare, unfortunately. But this woman, and it shows you, so there's nothing that, or rather there's something about being in a spoken environment, having words and language, can be written language, can be sign language, doesn't have to be heard, leads to the development of language processing in the brain. We know this from terrible things that happened in the kind of 18th century. It's a film about Caspar Hauser. So he's one of these wild children who's been discovered, who's never spoke, never heard humans speak, or children who have been locked up by foul parents. and if you there's a what's called a critical period if you don't learn language before round about your late just before your teens your grasp of language is never going to be very good your brain can do it but not quite the same way and this relates to why children you know children who've got parents from different nationality to the country they're living in speak two languages or more with absolute ease and you can learn yeah to speak all sorts of languages when you're a child when you're older it's much tougher oh yeah so this plasticity is partly a developmental thing so that's what happened in the case of this woman so the answer is speech localized yes it really is localized to left hand front hand side of the brain except yeah so uh you know it sort of doesn't have to be exactly yeah but it has to be it's only you're only going to get that if you are given that speech uh function you've got to have it around it's something about the environment is making the brain try and make sense of it and then produce a response to it in the same kind so let's say this couldn't be sign language if you're deaf it doesn't have to be spoken language but it confuses me a little bit to think that like okay so if somebody doesn't have a right hemisphere or a left hemisphere rather the right hemisphere can kind of take over that job implying that you know brain function could be localized in different sort of areas of the brain if that's the case then why is it that like with people who have sort of healthy functional brains they all develop you know the front left side of their their brains as the area of speech like why isn't it that you know you know johnny over here has it in the back right and he has it in the front or whatever i have no idea nobody else does i would say because yeah and so because we're still we're still well to put it lightly we're still pretty perplexed by the functioning of the brain yeah i mean this is about language it's about speech production yeah so it's not about language comprehension that is there are other parts of the brain that do that but speech production is very much controlled by this front left part of the brain uh and i mean if we can talk now if you want about the amazing astonishing mind-blowing stuff that was done in the 1960s about speech production uh well and the brain yeah so uh this is these are experiments which were originally done on cats so what you've got to realize is that your um your visual field is you've got your your retinas which is what detecting the light and basically the left hand side of both retinas are go to the right hand side of the brain so basically that means what you see over there is processed here and then the right hand side left hand which detect the left hand part of the visual field go there yeah so the the opposite to what you kind of might expect yeah but They're separated.

1:10:03So if you do a very careful experiment and you only show an image that can be seen by the left-hand side of the brain, then it's only processed over here.

1:10:16Matthew Cobb:Now, they were trying to understand how the brain integrates all this information. And they're working on cats in the 1950s. Because cats are very visual animals, so they've got a nice big visual cortex where all this is processed that you can record from. and they discovered that if they taught the cat say that an image in the left hand right left hand part of the visual system was um so processed over here just seeing it on the right hand side of the brain if you showed that but you cut the brain in two then only the right hand side of the brain was aware of that information the left hand side of the brain if you then tested it by showing the same image in the other visual field, it didn't respond.

1:11:02It's not seen it before. It had no idea what that meant. So the meaning, because you'd given it some food or something, was not being transferred across the two sides of the brain. Okay, that's pretty weird, but things got weirder because they then were working with humans. And these are patients, right? So you've got to remember these are incredibly generous people. These are patients who suffer from appalling epilepsy and have had operation, they're going to have an operation. They're going to separate the two sides of the brain because epilepsy is kind of an electrical storm in the brain. And one of the ways of stopping an incredibly bad epileptic fit, a very crude way, is to stop the message from spreading, stop the storm from spreading.

1:11:50Yeah, sort of slice the brain in two. You cut it in two. And in normal life, these people were absolutely fine. They just got on with their lives and they didn't have as much epilepsy and all the rest of it. So then the experimenters, in particular, a young researcher called Mike Gatzaniger, said, well, what if we did an experiment like we did with the cats? And they discovered exactly the same thing. That is, that if they showed something in this side of the visual field, then it went to the right side of the brain, that side went to that side of the brain. so of course you can ask you can say to the patient you can show them something over there and say what do you see and they'll say oh you showed me a picture of a cow but if you show it over there and you say to the patient what can you see this i can't see anything because it's this side of the brain that's responding yeah and it can't it hasn't had that bit of information it can't see it so that because the side of the brain that's responding is the left brain because that's doing that's control speech but the side of the brain that saw the thing is the right so that's that's pretty weird yeah that's pretty weird but then

1:12:59Matthew Cobb:things got weirder because they then thought well they noticed things would happen so for example um with one patient one woman patient uh they showed her uh left hand side so seen by the right brain a picture of a nude woman and they say to the patient what can you see and he goes you haven't shown me anything but then you'll start his then she was a woman patient she started laughing and they go well why are you laughing and she said well you've got a funny machine so she didn't know that the side of the brain that's talking to you does not know that this side has seen something rude in this case.

1:13:44Matthew Cobb:I mean, she blushed and everything, so she had a full response. It was embarrassing to her. But if you talk to this side of the brain, is there anything you can get a spoken response from, then you're getting... I don't know. I don't know. Some explanation. There's something happening to my body. My body's saying something. Wow. I don't know what it is. So I make stuff up. And they did loads and loads of experiments. Well, it's interesting, isn't it? Because they don't say... you know oh i don't know that they will make up an explanation well you would do i mean if you're you know if you're suddenly doing something you've got to find something to say right yeah i mean why am i laughing i don't know it's funny yeah so they did loads and loads of experiments and they found out that the although so you basically what's happened uh is right we know that the brain somehow produces consciousness yeah what's happened is they cut the brain in two yeah And now they've got two presences, minds, whatever word you want to.

1:14:42Matthew Cobb:And they're different because one can speak because it can control speech. The other can't, but it can say move, understand language. So it can move things around on a board. Draw pictures. Yeah, absolutely. Respond to you in all sorts of ways. And it seemed as well that there were slightly, they've done some really interesting experiments recently. I mean, the great and the sad thing is these experiments are coming to a natural end. Because this all happened, these operations were done in the 1950s, before they were adequate drugs, and these patients are now dying. And of course, there's no way that anybody would do this as an experiment.

1:15:19I mean, this is just too awful. But some of the later experiments they've done more recently suggest that there are actually differences in ethical views. So if they present people with a scenario about somebody tripping up and hitting somebody by accident, the left-hand side of the brain, the one that can speak, is much more likely to say, well, he did that deliberately. And the right-hand side of the brain will express the view that actually I understand what's gone on here.

1:15:49Matthew Cobb:So there may be other much more subtle differences between the two sides of the brain that we don't understand. Or it may be. So here's the problem, right? We know that this is actually controlling language, but we've broken the brain in these poor people. We've separated. It's a whole thing. And in some magical way, it has now produced two slightly different functionalities, two slightly different minds, because that's what's happened. Neither one has any idea that the other one exists. Neither one has any conception that things were different beforehand. They don't know. The left-hand brain can't tell you, oh yeah, I used to be much more sympathetic to people who dropped things on my foot.

1:16:32Matthew Cobb:It's not like that. They don't understand what's happened at all. And in normal everyday life, they just get on with things. Initially, they would have trouble putting on their trousers because their two arms were doing different things as they were trying to deal with everyday tasks. But very soon, they kind of chilled the two sides of the brain. so part of the problem is this looks like okay you've got these two sides of the brain and you know this ethical aspect okay well they clearly are more ethical view is stuck in the right hand side of the brain and a more kind of less less empathetic view of human behavior or interpretations would be in the left hand side of the brain but that's a mistake and it's a logical mistake that has troubled both neuroscience and genetics and it goes it's a method that says okay if we break something and or we change this particular thing in a system and something happens then that element we've altered is controls this yeah whereas if you just think about it well wait a minute so that what i was taught when i was a student this is back in the day uh we did have transistor radios but you know if you've got a radio or a circuit electric circuit and you've got a particular component you could take if what you take one component out and now you get this terrible feedback.

1:17:45And you go, aha, this is the feedback suppressor.

1:17:48Matthew Cobb:Because when I take it out, I get feedback. If I put it in, I don't get feedback. But no, it's actually just part of a system. You've got a whole system, you've broken it, and now it is malfunctioning. Gotcha. So although that malfunction tells you about the function of the system, it doesn't necessarily tell you something about that particular component. And this is something that has bedeviled neuroscience. So people take out bits of animal's brain and it behaves differently, they say aha this is localization of function yeah whereas in fact now it's not working properly um i mean another way of thinking if you think about a bicycle wheel you're a whole set of spokes and it is going to work really really well it's going to carry on you take spoke out it's going to be okay and another spoke and another spoke yeah and you go okay and then there's going to come a point at which the wheel will fall apart or it will break on you and you fall off your bike so there's a change from quantity to quality and it's a mistake to think okay well you know spoke number six that that's that was the one i mean you need to if you take out six spokes then you get a problem doesn't i probably would make a difference is where they were i guess yeah right about it you know um but it's complicated and it's not as simple and so like because in the face of and i've i've spoken about these split brain patients a lot like our listeners yeah most of the people listening to this who've seen this show before will probably have heard of these experiments because i mean they are extraordinary all the time when i first it was it was in the gold chris you know i i read the martians emissary and i since that day i have not stopped talking about it it's like on my bingo card of things that i talk about all the time um but like the natural sort of reaction to this is to think ah well okay we can experimentally test in split brain patients and show that the sort of brains are sort of split in two and that in healthy sort of functioning brains where the corpus callosum is still intact you know like they're communicating with with each other but the same thing's still going on we just can't experimentally test it but we have to be careful to say such that's almost certainly not the case right so the two sides are talking to each other all the time forming a whole yeah whatever consciousness is it's emerging out of the whole brain the fact that it can emerge in a different way in the two halves of the brain is telling us something but um i don't know yeah i mean because i was thinking i was thinking the other day i was going to make a a series of sort of novel arguments against the existence of god just like funny ones a christmas video and one of the ones i thought was like well if your if your brain is split into two hemispheres both of which kind of have their individual their own centers of consciousness and their own awareness of different things and what if you like convinced one of them of islam and one of them of christianity you know would that person get to go to heaven or not and i don't think that religious traditions have sort of adequately uh accounted for that but i suppose in a split brain patient you could kind of do that i i my guess is that religious scholars of all religions if you pose them the problem what's happened to the soul yeah and these individuals they would have an answer i don't know what it would be whether you've got have you got two souls or have you just got one that is slightly different or do we just go with the one that can speak and say the prayers or whatever it could be comparable to someone who's like you know on monday they're feeling pretty religious and then on tuesday they're not you know it's like what happens to that person well they're kind of both of those people at once even though it sort of changes a little bit over over time maybe it changes over space too but it does i mean it massively upsets like a lot of our understanding about like let's say personhood or the unity of self right because we've got at least in these specific circumstances people who for all intents and purposes act like a single person and yet there's sort of a little bit more going on so and yet when you connect them back up again you know the brain starts sort of it's like completing a circuit and the whole thing starts working together again and yeah the brain is in two hemispheres even even without the split split brain hemispheres that the brain is is built in sort of two parts and there seems to be an evolutionary advantage to that because you know it happens across different animals so then what is the relevance of this separation of two hemispheres in a brain that is connected up properly i mean it's one of the i mean it's not just the brain of course we are symmetrical yeah um i mean not entirely so you've got one heart not two unless you're um unless you're from gallifrey um you got one heart uh you got one liver so it's not entirely symmetrical but we are base we are bilaterally symmetrical organisms and one of the mysteries one of the things we don't fully understand is that the evolution of a of bisymmetry uh of symmetry of bilateral symmetry occurs at the same time as what's called cephalization.

1:22:27Because if you think about it, you are most definitely not symmetrical that way.

1:22:31Matthew Cobb:You've got a head and you've got feet and you've got a front and a back. So in two of the key dimensions, you are most definitely not symmetrical. And what happened around about 550 million years ago is that as, I mean, scientists can't define the brain, but let's just say it's a

1:22:56not only this cephalization, so the development of this putting neurons together at the brain, also goes with the development of a mouth and an anus, because that's the other thing you've got.

1:23:05Matthew Cobb:It goes in one end, it comes out the other. And the sense organs are tending to be accumulating at one end, and this enables you to be symmetrical, because it enables you to detect where food is coming from, or where a threat is coming from, because I'm here, and so I can see that, or sense, the stronger sense if the predator's coming from over here, I can feel the vibrations in this neuron, this set of neurons more so than in this set of neurons. So then you tend to, in evolutionary terms, you end up with these neurons all kind of being stuck together. So the symmetry is a deep developmental, an evolutionary developmental thing that is going to be related to our various earlier origins as animals that are becoming bilaterally symmetrical and cephalized.

1:23:51And also with our, I mean, we have a spine, we're dorsal. We have a dorsal nerve cord. Whereas if you are an octopus or a fly, then your nerve cord is ventral. It's down your tummy. So there's a complete separation of the animal kingdom that occurred very early on with these two different ways of organizing yourself, which are, I mean, the big difference

1:24:14Matthew Cobb:is that if you just think about it, I've got my throat here and my brain there, all my neurons are going down past the backside of my throat. Whereas if you're an octopus or a slug, and that's all octopuses are, apologies to Peter Goughby-Smith, they're just smart slugs, or you're a fly or a bee, then you've got your brain here. And because your nerve cord is ventral, it's got to go round your throat. So basically you have a brain that's kind of like a donut shake because it's got to go round your throat basically and then it goes down the front of your body. So the short answer I think that the symmetry is a consequence of those developmental steps that were taken deep deep in animal history and that's why all animals have got symmetrical brain.

1:25:07And so then today, what do these symmetrical brains do for us? It seems like you're sort of saying most of the time in a healthy brain, the whole brain is active, and yet we can kind of localize certain activities, and some of those localized activities will be on one side or the other. We've said a few times that the processing of spoken language, for example, is in the front left of the brain but at the same time you probably want to say but that's that's too simplistic that's like an overview but then what's the what's the actual answer you know where is

1:25:42Matthew Cobb:where is speech stored if not there well i mean speech control of speech is stored is there that's to do with that and that's why if you have a stroke there as brocker discovered you are likely to lose the power of speech you still understand it you could write it but you can't speak so in that in that case at least the the left hemisphere could be said to do speech yeah in the right hemisphere they're not to they're doing something else and that is quite a quite a division even in a healthy functioning brain that's communicating with itself um i know it would be a fallacy perhaps to assume that in a healthy brain like there are sort of two centers of consciousness exactly but do we get do we have sort of good reason to the contrary or should we remain sort of like agnostic like could we look at that there's any evidence for that at all no i mean quite the opposite that whatever consciousness is it's emerging from the brain or parts of the brain as a whole and even when you try and so there's this argument about localization of function is still going on i mean there's a right on the train down i was reading a new big review all about how cognition is both distributed and localized yeah um and it changes over time uh and i mean one of the things that I try to do in the book is partly because, so though I have a degree in psychology, I've spent all my academic career studying insects.

1:27:06So took a kind of reductionist approach. Let's see if we can understand simple systems. So for example, a big study just came out looking at a tiny little worm called C. elegans, which has got about a thousand cells, 300 neurons wow so its brain is about eight cells so we know everything about these animals absolutely everything and they just did a huge study of looking at the recording from all the neurons all 302 neurons whilst the animals were doing various things wriggling about turning finding food very very simple things and you might imagine if you're building a robot you say okay well i can make it you know you could make a robot do that you could get a robot that could detect a particular stimulus and then move to a particular place where they can find that solution.

1:27:57And you would have, your computer would have functions hardwired into the components.

1:28:02Matthew Cobb:But what the animal does is those neurons are doing all sorts of things and those things change, their functions will change over time. Some of them are paying attention to past states, some of them are just interested in what's happening at the minute. If you go back and test the animal again. It's going to be different sets of neurons, even in such a simple thing. So it is really, really hard to understand how this is happening in our brains. Now, there is a counter-argument that is, I think is quite interesting. Somebody put to me the other day that, okay, so what you're saying is that identifying it at kind of the atomic, the atom, the particular level of neurons is going to be really hard.

1:28:48Matthew Cobb:But do we need to do that? So climate change is a reality. We don't understand how every atom of air is moving about in the wind where we deal with much larger scale problems. And I think that's a good argument. And I think that large scale studies of brain function, and in particular in humans, who are very interesting, obviously, to us and present the most complicated case, are absolutely valid. And I don't think that's not something that's worth doing or anything like that. But there is the weird thing about the brain. So consciousness, if it's anywhere, is thought to be in the outer layers of the brain, in the cortex.

1:29:32Matthew Cobb:And in particular, there's bits at the back of the brain called the cerebellum, which as far as we can tell, their control in movement and gait and all the rest of it but they don't seem to be involved in consciousness so we've got some neurons i mean bazillions of them and not just the neurons we always talk about is neurons you've got to remember we've got 80 billion neurons in our brains but they're also things called astrocytes which envelop the neurons there's the chemicals that it's flop they're all flopping around in the hormones and all the rest so it's a really complicated system. But it's just those structures, some structures are producing thought somehow, and others aren't.

1:30:15What's different? I mean, I said I'd just finished writing this biography of Francis Crick, and one of the things that he was interested in was finding what he called the neural correlates of consciousness, which is not the same as this is what consciousness is or where There it is, but we can find a set of neurons that are responding whenever a particular thought or perception is taking place. Yeah, the neural correlates. So like what correlates in the neurons with the conscious experience. Yeah, absolutely. So that doesn't mean, I mean, it may be that, because it's a correlation, that it's something else that they're both involved in, but it's a start.

1:30:50And his questions are very useful. He said, well, where are these neurons? is there anything special about them in terms of their structure or the genes they express or is there anything special about them in terms of how they're firing or how they're connected up

1:31:04Matthew Cobb:those are the questions we need to answer and i think whilst the the climate change argument is good we can't get away from the fact that ultimately whatever consciousness is it is emerging from the properties of these incredibly complicated neural networks that are in our brain and are communicating on the two sides. And you don't place much stock in the idea that, you know how the debate originally would have been about, are there certain parts of the brain that are responsible for certain behaviors, like speech or the left-hand side of my pinky finger or something? Is that different areas in the brain and memory?

1:31:41Do you think there's a similar debate to be had about, are different parts of the brain responsible for different parts of consciousness? Like, you know, there's your emotional self and your rational self and your sleeping self. And maybe there's like different parts of the brain. Or do you take what I suppose would be a more Cartesian view philosophically that it's all like one thing?

1:32:02Matthew Cobb:I think it would be terribly mealy-mouthed. Well, a bit of one and a bit of the other. I mean, in this review I was just talking about, it was characterizing the extreme position is, you know, cognition and ideas and thinking is everywhere. everything everywhere all at once that's the extreme view it's all going on man but i've already indicated it's not everywhere because the cerebellum doesn't seem to be involved but uh it is on the other hand both district i mean all i can say is it's both distributed and localized but the localization as i say it's fuzzy and where we can really identify localization of perception it moves at a cellular level.

1:32:45Matthew Cobb:And this is kind of mind-boggling. So I think what people have to realize is that simple neural networks remain a mystery to us. We might think that it should be relatively straightforward. But it isn't. The example I give is the work of Eve Marder. And she spent the whole of her career, she's still active, studying the lobster's stomach. and the lobster's stomach is a bag that has got lots of muscles in it that grinds its food up and there are around about 30 neurons controlling the activity of these muscles and the muscles do two rhythms and dr marla knows everything about those neurons she uh can dissect them with both the scalpels and chemistry and genetics.

1:33:38Matthew Cobb:She can model their activity, and yet she cannot explain why the 30 neurons produce those two rhythms and not other rhythms when models suggest that they should be able to do something else. She can't predict either what will happen if she takes out one of those ablates in the technical term. You remove the act, stop one of those neurons being active, what happens to the rest? The network starts breaking down. Now, one level, this isn't surprising. Physicists have something called the free body problem, whereby they can predict accurately using Newton's laws, the motion of two objects in space, but then if in randomly moving around each other, but then if you add a third one, it all gets chaotic and they can't predict what's going to happen.

1:34:23So we know that very simple systems can produce very odd kind of behaviors. So if we don't understand the lobster stomach,

1:34:33Matthew Cobb:poor old Dr. Marder can't, you know, figure it out. And that's not because she's far cleverer than I am. And she had loads of researchers working with it. It really is a massive, massive problem. We can see some of this in an object that excited in years after the First World War as ideas about information and code started to emerge long before the development of computers. It all emerges from messages being sent during the First World War, which is also when they started to use radio, of course, and had amplifiers, which could amplify weak signals. People then start to record from neurons and start to say, ah, then it's not just a message, it's a code that's going down the neuron.

1:35:17There's information in there. um that uh somebody's writing a popular book about uh behavior and so on this man called locker is mainly known as an ecologist and he had a a little wind up uh what in the uk we call a ladybird a ladybug in the us and this shows an incredible emergent behavior i can look do you

1:35:40Matthew Cobb:want to do you could maybe record it i've got a uh i've got i've got one with you yeah so we need put it on a leg. Oh, we're so good. And it moves a lot and it is amazing. I mean, I've done it in display. So when's this from? Well, this is a reproduction. So it's a repro, a retro, there you go. Yeah, okay, I see. Because these were popular when? In the 1920s. So it's entirely clockwork, right? You've got to remember, it's entirely clockwork. There's nothing electronic in here. It's got those little wheels. I've just wound it up. Give it another wind. It's got these antennae that move at the front.

1:36:13Matthew Cobb:Sure. Is this big enough? Yeah, yeah, it's fine. Well, we'll see. Okay, I'm going to put it down, and it's going to go straight forward, and then we'll see what happens. Kayak gets my flight, hotel, and rental car right, so I can tune out travel advice that's just plain wrong. Bro, Skycoin, way better than points. Never fly during a Scorpio full moon. Just tell the manager you'll sue. Instant room upgrade. Stop taking bad travel advice. Start comparing hundreds of sites with Kayak, and get your trip right. Bad advice? You talking to me? Kayak. Got that right.

1:37:26EbbGliss.

1:37:45Ask your doctor about EBCLIS and visit ebglis.lily.com or call 1-800-LILY-RX or 1-800-545-5979.

1:37:56Look at that. That is crazy.

1:38:02Matthew Cobb:So it looks purposive. Isn't it cool? And it really is quite an extraordinary kind of thing. Okay, should I show you how it works? Yeah. I'll stop it making a noise now. Hold it. So it's got the friction motor, the wind-up motor. Yeah. And this and this are the key thing, okay? So this little wheel here, if you can see it in profile, that's a free wheel, and it's at an angle. And these little antennae keep the whole thing, I don't know if you can see it in profile, you imagine this is not quite as deep. So normally, when the antennae are both down, it keeps this out of contact, so it just goes straight forward.

1:38:42Matthew Cobb:But when the antennae drop, like that, as it goes off, then this comes into contact. The little free wheel comes into contact, and because it's at an angle, it will now turn the motion from a forward motion into a sideways motion. I see. So having a look at this down here. Alex is trying his best here as well. It's still rolling. So what will happen is that antenna will sort of... As it falls off the edge... We'll call it to fall and it'll hit that wheel. Yeah. And that wheel will essentially steer it around. Yeah. Right. And so it's always going to go the same direction. It will stay on the table.

1:39:20Matthew Cobb:Yeah. So much. It's always going to turn the same direction. If it was angled at the other direction, it would go the other way. Yeah. That's pretty neat. Whoa. Okay. So what did we just, I mean, that's pretty neat. A pretty cool, you know, Christmas or birthday present perhaps. perhaps, but why is that relevant to brain science? Well, what it's showing is, one, you can get what looks like purposive behaviour out of a very simple system. Here we've got, I mean, there's no electrical communication or anything like that. It is simply the way it is organised, it's set up to be able to produce something.

1:39:57Matthew Cobb:So one thing people should take away from that is just because it looks like it's purposive doesn't mean to say it is. and the same is true when you talk to chap gpt right right just because it's giving you some advice that means say it understands anything humans are very um are very bad at being suspicious about things yeah uh we tend to assume and we have to right this is part of what uh is called theory of mind that is we have to assume that other human beings feel the same things and think the same way as we, I mean, they are basically human. I mean, clearly at times, war, conflict, then we pretend they're not and we dehumanize them.

1:40:41And so they are other and they must be killed or whatever. But in general, human society works on the basis that I assume that you're not a robot from Mars. You're not a figment of my imagination. I mean, I can't prove either of those things, of course. That is possible, but very unlikely,

1:40:55Matthew Cobb:not terribly interesting at the end. But so we assume that other humans behave that think that way we also assume our pets do everybody you know yeah go yeah my dog of course it's conscious you know but that's simply because you're projecting i mean maybe but really it's you projecting onto the animal same with the you know when i was at work i used to shout at the at the photocopier yeah you know so there's no point in doing no basil faulty thrashing the car yeah because you treat it as a thinking object so the key the key point is that has shows what appears to be purposive behavior but then you've got to think about well what is happening there okay i understand how it's set up and what locker argued is that the whole device the whole thing that functions it needs to have all all those parts and the device as a whole is somehow construing he put it construing the information from the the little antennae that it's now if you think about it as a functioning system yeah then that is the way it's working but there's no actual transmission of information.

1:41:58Matthew Cobb:It's simply an alteration of the structure. So whilst we can understand how that very simple robot works, understanding a real 30-neuron system in the lobster's stomach or a 302-neuron worm wriggling around for the moment, that remains beyond us. But there's something about the organization of things, their structure, which enables particular functions to emerge. And that is the same in the case of the brain and consciousness, but that is at the moment unknowable. Now, I don't think it is forever unknowable, but I mean, it's partly because I don't work in the area, so I'm not kind of despairing at trying to figure it out.

1:42:48Matthew Cobb:And I mean, opinions differ over this. So, you know, studies of consciousness, When I was an undergraduate in the 1970s, I remember us sitting around, and it's partly because Francis Crick had just stopped working on molecular biology and so on, had gone to America to work on neuroscience and he was going to study consciousness. And we knew this. And we kind of laughed and said, oh, yeah, he's going to crack consciousness. Oh, yeah. And so we then said, well, what do we think consciousness is? And we said, well, it's some kind of emergent property of the brain. And that's it. How could we study it?

1:43:22Matthew Cobb:No idea. uh so i i've never worked in this area crick was much more precise and more thoughtful than i was as a as a young man and came up with this idea of we can try and find the the correlates of of the neural correlates of consciousness but he was very limited in what he was trying to do he wanted to come up with a very precise hypothesis that could then be tested experimentally and my impression of the field of consciousness studies in particular, although he helped make it a thing, he turned it into a popular scientific, an acceptable, let's put it that, a respectable scientific activity, not simply something to be left to philosophers who've been thinking about it for, you know, whatever it is, 3 ,000 years and haven't got anywhere.

1:44:10Right, we can now work it out. Now they haven't and things have got really complicated so the most recent article i think suggested there were over 250 different theories of consciousness yeah which to me says you don't know what you study another guy from from closer to truth i've forgotten his name it's like a tv show that's also on youtube i think he and maybe some other people have just produced this like interactive map and this is i think probably more like philosophical theory of consciousness but you can either see it as like a connective map or like there's a big list and it yes this i don't know if it's the same list that we're talking about i think it is it's like hundreds of them yeah and you can click on them all and there's i'll link in i i think it's it's it's awesome and it'd take forever just to just to get through them but it's it is also in a way a little bit depressing yeah but it shows we don't know what

1:45:01Matthew Cobb:we're talking about right you know because they can't agree what i mean most of those studies don't in the scientific versions don't try and say okay well our version is better because we predict x and your theory doesn't predict that yeah they don't that doesn't happen they they all kind of work in in separation it's the beginning of a change in that respect but above all their theories of everything their theories that try to explain everything all at once and crick and i tend to follow him on this his view was that that was the wrong way to go we needed to do it very piecemeal and just try it getting there now that having been said his and his colleague Christophe Koch, their search for neural correlates of consciousness, in a way we found them.

1:45:43So one of the things that Koch did after Crick's death in conjunction with some neuroscientists and neurosurgeons in Los Angeles, Ishak Freed, main researcher, they were again working on patients who had terrible epilepsies. So they were going to be operated on. They weren't having their brains split or anything. But these incredibly generous people said, yes, of course you can poke around in my brain and record from my cells in my brain whilst I'm getting prepped for the op. So they're amazingly generous. Yeah, that's one. And it always goes, you know, wow. Anyway, so they're going to have an operation that's going to do various things to their brain to reduce their risk of epilepsy, very, very severe epilepsy.

1:46:25And what they did was to record from single cells in the brain and the visual processing areas, and they would show them images. and they would show them a picture of the Sydney Opera House or of a differential equation or of Jennifer Aniston. And they would find cells that only responded to those very specific images. In the case of Jennifer Aniston, notoriously, there was one patient who had a cell that responded to Jennifer Aniston but would not respond if there was Jennifer Aniston and Brad Pitt.

1:47:00Matthew Cobb:so you know these these were neural correlates of consciousness this was their visual they're saying okay it's brad pitt that's a sydney opera house that's a differential equation yeah and this single cell one cell yeah is firing away now this is a bit of a um a cheat or it's not a cheat it's a it's a problem of optics so they've recorded they're recording from single cells wow that's amazing is that the only cell in their brain that represents jennifer aniston almost certainly not. What it will be is you can imagine, I mean, in a way, all it's saying is, well, our perceptions, the activity of neurons, that's all there is, you know, there's nothing else except neurons, you know.

1:47:42But what it goes against, I mean, clearly, we cannot have a single cell for every possible thing we could remark, we could detect. Our brains aren't big enough, you know, because we can see all sorts of things. I can see you, I can see the cameras, the chair. Yeah, you can see like Jennifer Aniston's left ear and you know like you can I mean Jennifer Aniston standing on her head is that

1:48:00Matthew Cobb:the same as Jennifer you know clearly then have we got two cells for that right you heard a left profile left profile it clearly is bonkers um and what there must be is you're going to have a set of neurons that would recognize blonde woman in her 30s uh and then another set which would actually be much more specific of actually Jennifer Aniston. And they were recording, by chance, from one of those cells. I mean, you know, that cell responded to Jennifer Aniston and nothing else, quite possibly it's part of this network. You can't go to the same place in the different patients because our brains are so dense.

1:48:38And what that representational drift business I was talking about much earlier on suggests, if the same is true in humans as it is in mice, which my guess is that it is that if you were to leave that electrode in place and to come back a month later and show the picture of jennifer aniston maybe that cell wouldn't fire not because the patient didn't know who jennifer aniston was but because those thousand say cells had now moved on somewhere else in the brain just they're shifting for reasons we don't understand yeah that's so

1:49:09Matthew Cobb:incredible yeah we've got neural correlates and then what it hasn't actually i mean so crick was and cock this was their big thing i think they were really this is the best approach but we're kind of stuck and that's really the theme of the book um and it struck me when i was you know they were all in the in the in the tens 2010s there are all these think pieces by uh neuroscientists saying we've got all these data from uh what are called connectomes how neuron brains are wired together all this other information we can't make sense of it we we got too much data and not enough theory to try and explain what should be going on right i see and okay i i know it's a it's a it's a big topic and you've got a whole chapter on it but just as an overview we've used the word neuron a few times neuron and um people might sort of roughly know that that's what the brain's made out of but what is a neuron well it's a cell it's a cell it's a responsive cell uh with normally an input at one end and an output at the other end.

1:50:15Matthew Cobb:And there's the dendrites, as they're called, which are loads and loads of the input part. And then there's the cell body, which has got a nucleus, which enables it to function. And then you've got a long thing called an axon, which sends the message on to the next part of the processing network. And these neurons, these specialized cells, they will interact with each other. So, for example, in And again, to show how amazingly complex simple organisms are, people have studied the cell wall of a maggot. So a maggot basically wriggles along. And it's got a repeated nervous system in there, which enables us to do this.

1:50:58And you've got little cells that say, I've stretched. They respond to stretching. So when the maggot pushes forward, these cells stretches. And it's basically telling the system, okay, I've stretched. Don't go any further. We'll burst. We've got to now stop stretching and do the next kind of movement.

1:51:14Matthew Cobb:And those single cells that are simply saying, I've stretched, not even to the maggot's brain, but to a little circuit, movement circuit, they have around about 100, they have about 100 connected to 132 other cells. And those connections are not like in an electric circuit where it's just a plus or minus. They will have many, many neurotransmitters because that's how the chemical electrical signal is transmitted from one cell to the other through these chemical connections. And we have lots of different neurotransmitters in the same system that can do more than one thing. So they can modulate the activity, turn the next neuron off, turn it on, excited or whatever.

1:51:56So it is not a series, it's not like a computer. I mean, it's so unlike a computer. It is not a digitally based system in that if you shine light on a cell that can detect light, it doesn't just go on and then go off. It will fire with greater intensity with more light.

1:52:20Matthew Cobb:And things get even, they're even more complicated. It can show changes in the shape over time as well. So neurons are basically kind of the connecting parts of the nervous system. And when they're in brains, they start, or when they're in connection networks, they start to do very complicated things that we, as I've tried to explain, we've found very hard to understand. And somehow, some of those neurons in your brain right now are producing your perception, your thoughts. Yeah. and that intangible, weird, spooky thingness that's consciousness. And how that happens, I have no idea. And anybody who tells you that they have an idea is talking crap.

1:53:10Matthew Cobb:When I finished the first draft of the book, I sent it to my editor and he goes, he sent back, he said, well, this is all very well, very clever and all that, but how does the brain work? I said, well, we have no idea. And he said, we can't say that. Every book about the brain explains how it works it's quantum this or it's what it's computer whatever yeah and i said yeah but all that's rubbish i mean that's just to sell books yeah maybe i said you know the usp the unique selling point of my book would be i tell the truth that we do not know yeah it's it's the publisher thing isn't it like you know publishers are very keen on like like in the world of philosophy you know publishers will sort of say you know this book it's a cool idea but But I'd really love for you to just do a chapter on how to find meaning in your life and stuff.

1:53:57And you're sort of like, I'm not quite sure you understand the project. But I understand you've got to sell books. And I think people are beginning to get a bit tired of that as well. I think if you walk into Waterstones and you see all of the new books and they're all very certain. They're all very like, here are like 14 principles to follow that will fix all of your problems. or here is the explanation for this or that or whatever, or like a comprehensive history of the world in like, you know, 18 screwdrivers or something. And it's cool. Yeah, I'll buy that. That sounds great. It's interesting, right?

1:54:33But I think it needs to be presented as this is, you know, my theory, my idea. It needs to be tested against the evidence. And as a historian, right, which is the sort of cap that you're putting on when writing a text like this, it's not your job to say...

1:54:45Matthew Cobb:Well, yeah, except I don't have... I mean, I don't have a dog in the fights, the many fights, and I don't work on the brain, right? But I am, or was until I retired, a neuroscientist. So I'm both. So I can see, and what I also wanted to do was not simply to tell the story and say, look, we've no idea, let's go home, but quite the opposite, to actually sketch out, these are the possible futures. So I say sometimes, say facetiously, the books divide into three halves, past, present, and future. And the future bit, again, I didn't want to write that. So there's a future is the final section where I try and predict what's going to happen, which is not something that scientists do for historians, right?

1:55:25It's just, but the publisher said, we really need that.

1:55:28Matthew Cobb:You've got to say, where are we going? So I said, okay, well, you know, predictions are mugs game, especially about the future, but I'll try. And so it was actually, that was really interesting to try and think, well, what are we going, I mean, what are we going to discover? How could it be done? And I there lay out my own kind of prejudices, which I've outlined here, which tend to be more about understanding simple systems in the hope that something of the principle of organization can emerge, that we can then apply to more complicated things. In other words, I would largely, personally, put the problem of consciousness and how it works and how it emerges on the back burner until we've got some better idea.

1:56:10I mean, very famously, Christophe Koch had a bet with David Chalmers, who's the philosopher who came up with the idea of the hard problem i what are called qualia why i feel the what what the feeling of consciousness is and caught very ambitiously in this is in 1998 i think bet him a case of fine wine that within 25 years we'd have solved this problem uh he lost very graciously yeah um but i

1:56:36Matthew Cobb:mean i you know my view where i normally point to stuff i know about so the maggot brain i've I spent most of my career studying, as I say, tiny insects, maggots, very simple systems. We have the connectome of the maggot brain, which is about 5 ,000 neurons, something like that. If in a century we can predict everything that that can do and say, okay, we take out these neurons or alter their activity in this way, this is what the animal will do. And we understand everything about it, I will be amazed. And that is the, and I think these, whilst many people think, well, okay, well, this is an insect, we don't care about that.

1:57:18What about the hard problem or wherever? I mean, the reality is that we aren't going to, I mean, unless we can solve the other problems, I don't think we're going to be able to solve the big problem. And we've seen this. So this has happened repeatedly. Every kind of breakthrough we've made since the 1870s, been a huge breakthrough say in discovery of electrical activity in the brain and some localization of function and then people go oh my god how are we ever going to figure out how consciousness emerges my god if it's not some mystical spirit which is just a get out all right you know if you think it is a material thing that is a consequence of neuronal activity how are we going to explain that same thing happened in the 1950s when they developed the first eeg recordings so you can record from the activity the overall activity of the brain and this looked fantastic great insight you could record from or stimulate bits of the brain and you'd get people remembering things most bizarre things like oh i can see my mother telling me off because i've put my my duffel coat on upside down or whatever and most bizarre things or people could

1:58:26Matthew Cobb:got earworms they started singing along because they could hear a tune being played wilder penfield Yeah, that's right. Wilder Penfield. Sort of discovers this. Yeah. And again, working patients and recording and stimulating their brains and getting most as they were being operated on for other reasons. These weren't experiments in that sense. Instagram teen accounts have automatic protections for what teens see and who can contact them. Plus, time management tools. And Instagram will continue adding built-in safety features to help create age-appropriate experiences. Learn more about teen accounts and Instagram's ongoing work to protect teens online at instagram.com slash teenaccounts.

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2:00:09Matthew Cobb:I could make you do that. I would have to know what the trigger was, as it were. So I could do that with a sense of smell. So if you think of Proust's La Cheche du Temps Perdue, so Remembrance of Things Prast is the most used English translation. It's a huge long book about experience and so on. It begins with him saying, you know, I used to go to bed quite early and my mother would bring me a Madeleine, one of these nice biscuits and she dunk it in the in the in the tizan in the wheat tea that he would eat and he he he can he remembers this because he he's doing this and the smell and the taste of the food takes him back and we've all had that you know you smell i don't know a particular food that your grandmother used to cook and you you remember it like you're back there she's up here you're that high and the you know the counter's at this height you know you're three years old in the kitchen as she's cooking something like that so smell is in fact very able to produce these dreamlike uh very realistic memories that are not the same as us uh struggling for the name of phineas gage yeah it's rather different there's no tip of the tongue phenomenon bang you are there you can remember it do we know why smell is so connected to memory um well as things we're experiencing things, it seems that, I mean, again, this is partly because a lot of what we know comes from animal studies and then from a few patients.

2:01:41Matthew Cobb:But we know that we are tagging events, key events tend to get tagged with smells that are associated in the environment, but also with place. And we can manipulate this in animals. So for example, you can make an animal remember a smell that it's never smelled. So if you know the particular set of neurons in a mouse's brain that are activated by stimulating the smell of aniseed or something, and then you will make it respond to that by stimulating those areas, activating them using optogenetics or whatever. So you can actually reconstruct bits of memory that have never happened. Yeah, that's strange.

2:02:27Matthew Cobb:I mean, it's in an animal. We can't do this in humans, but clearly science fiction. Philip K. Dix talked about this, we can remember it for you wholesale, which has turned into a film and all the rest of it. So memories, I mean, they can't be plugged in. Elon Musk wants to get a language module and you stick it in and all of a sudden you can speak Italian or whatever, or you can remember things about quantum physics that you were never taught. That's not going to happen. You know, brain computer interfaces don't work that way. And I don't think it will, but there is this tagging of events, uh, that are taking place and smell partly because it's one of the oldest is the oldest sense.

2:03:10So it's the one that evolved. It's just detecting chemicals in the environment. Ah, sure.

2:03:15Matthew Cobb:Yeah, of course. So you get, you can smell in water fish smell. So we were smelling long before we had eyes, right? We were detecting chemical gradients in the environment and we were moving what we, you know, our long ago ancestors. You know, little worm-like things. So smell and memory are very closely linked. And in humans, memory is partly one of the gateways to it. The way that memory is then stored is through these structures called the hypothalamuses, which are deep down in our brain. and uh again one of the things the experiments that went wrong uh this was studied by wilder penfield and brenda milner who is astonishingly still alive and i think she published a lot she's about 103 she's canadian psychologist one of these patients called hm yeah uh that was his real name is because he's dead now and so his name's been revealed as uh henry mollison these patients were having an operation because they had terrible seizures and so on.

2:04:21And basically, the surgeon who did it was a hacker. And I mean, as he just had kind of hacked around, and he drilled huge holes through the brain and destroyed, it was supposed to be simply taken out small areas, and basically destroyed HM's memory system in that he could not form any

2:04:41Matthew Cobb:knew permanent memories after that day, pretty much. So what that meant was that he knew everything that happened up until he had the operation, but every day he lived it anew. He couldn't remember anything. So Brenda Milner worked with him for decades, did experiments on him, trying to work out. His olfactory system was also damaged. He couldn't identify smells anymore. He found it very difficult to navigate, to read maps and so on. But she did all these tests on him, and every time she had to introduce herself yeah hello henry i'm i'm here to do some experiments oh that'd be great love to help you yeah and of course she she knew that she knew him yeah and he had no idea now it's interesting that it doesn't seem to have been completely uh you know his his um isolation a terrible terrible isolation can you just imagine you don't know anything from this event in 1952 or 1951 when the operation happened but he did he could later on so for example he knew about the beetles he mentioned them he knew about landing on the moon so this awful awful operation botched operation yeah didn't completely destroy his memory but you had to you know there are only very very few things that escaped the yeah the destruction of these two structures in his brain and we're back to the the problem of in what does this mean does it mean that the the hippocampuses are the site of memory or rather that this more likely it seems this is the place through which memory is then rooted that jumps out at me yeah it seems to be much more likely that's the latter memories are distributed uh so i've said earlier on this perceptual drift is not happening in the hippocampus it's happening elsewhere perception and so yeah it's sort of like and and that original operation that you're talking about wasn't it someone who i mean you're talking about a lobotomy and this was at a time when it was a self-admittedly experimental sort of form of medicine and this guy had been sort of trying to treat people with schizophrenia and then this like henry was having like epileptic seizures and he kind of just tried the same technique even though it was dubious in the schizophrenia case too and he just sort of destroys part of this this this guy's this guy's brain um and the idea that yeah the hippocampus is clearly key to memory here but to think that that must mean that that's where memory is done or where it's stored it's like maybe a bit like sort of if i like plastered over the front door of a house and there's no way to get into the house anymore i went like oh look i can't get into the into the living room anymore you know that the living room must be sort of stored in the in the front door it's it's like a sort of yeah a sort of the wrong way of thinking about it but we know that the hippocampus is incredibly important and there's again dubious i wanted to ask you about this because i think it's dubious but i'm not sure how dubious it is the london cabbies thing like black cab drivers in london have have bigger hippocampuses but they've not been able to to replicate that that test right yeah well it yeah Well, it hasn't been replicated.

2:07:51Matthew Cobb:I don't know if anybody's tried. I mean, but so this is the issue. So in animals, the hippocampus is associated with place, identifying place. And there are these things called place cells, which very carefully, very deliberately exactly tell a rat or a mouse where it is in the environment. And events are tagged with that. So if you find a bit of food in that corner, then, you know, those cells are really, really activated because that was great. Now, those cells have not been shown to exist in humans. Really? Now, we're not rodents. So, you know, part of the problem is you've got a model, an animal model, you know so much about, and you then extrapolate because they're both mammals.

2:08:28Matthew Cobb:But we don't know that they're in the hippocampus. Yeah, they're in the hippocampus, absolutely. They were discovered by accident. They got a Nobel Prize for it, but they did discover it, but they were looking for something else. As so often happens. I can't remember who it was or anything, but this experiment was trying to sort of measure a part of the of this like mouse or rat's brain and then as the rats moving around it's lighting up like crazy and they're like gosh something crazy must be happening and it turns out they just accidentally stuck it in the hippocampus yeah well they only knew that after they chopped the rat up yeah yeah right oh where were we oh we weren't there okay that's interesting so maybe it's the hippocampus yeah but i mean clearly something similar is happening we've got some way of encoding space i mean yeah i i have a very good sense of direction uh and in general when i I know where I am.

2:09:12And if I don't know where I am, I find it very disorienting. I know in London, I know I go down Charing Cross Road and I'm going to end up at Trafalgar Square. My wife, she comes out of the tube. She doesn't know. She has a very different sense of direction to me.

2:09:27Matthew Cobb:So we know that the hippocampus is involved in this kind of activity. And there is this claim from this study in London that taxi drivers who have to do what's called the knowledge. So if you get in a London cab, they're not going to use sat-nav. You're going to say, I want to go to Golders Green or whatever, and they will take you there. And they'll take you by the quickest route and all the rest of it because they have to learn it. You've got to learn the name of every street in central London. You can watch them doing it on YouTube where they're doing the test and someone will sit there and go, OK, give me King's Cross Station to somewhere in Shoreditch.

2:10:03and they sit there and they go right you take a take a left down this street a right down that street you know follow it around to the it's incredible and and you still today if i'm in a rush it's a it's a black black cab in london every single time because they know yeah they know what's

2:10:18Matthew Cobb:going on so london's quite unique most cities like manchester we have you know the taxi driver but you either tell him where to go or he puts a postcode into his uh into his saturn yeah but taxi drivers in london have to do the knowledge and so the claim was that by scanning their brains they found that taxi drivers had larger hippocampi than you or I. Now, there are a number of problems. Firstly, with the arrow of causality. So maybe you can only pass the knowledge if you got a big hippocampus. They didn't do a developmental, didn't do before and after. Here's you, you don't know any street in London, now you know them all, have your hippocampuses got bigger.

2:10:57Matthew Cobb:So that's one problem second problem is you know the hippocampus isn't very big i mean our brains aren't really very big you know they're kind of this yeah this part and the hippocampus is i don't know about that big so is that size of what like a walnut yeah a bit smaller and the kind of elongated shape supposedly looks like a like a um like a seahorse which is a bit strange but anyway yeah they thought it looked like a seahorse hence its name um but the the scanning methods that even now the scanning methods very very noisy yeah so it's very difficult to be able to say okay you've actually increased you know they may well have increased significantly in volume in the test but whether that is a real you know you're relying on this very fuzzy measure so i think most people are the dubious about this but we know that in in rodents at least there's this kind of almost like literal mapping of an environment absolutely in the hippocampus it's not just like you know you're walking around the environment and then you sort of write it down in a bit of code that's in the hippocampus it's like i was trying to understand how this worked because it took me a minute to figure out what was really going on here but as far as i understand if you sort of you know you measure like a particular neuron right in the hippocampus and you just sort of stay locked on that neuron and then you watch this rat run around then if it passes by a particular area the neuron will fire and then it'll keep running around and if it goes back to that area it'll fire again back to that area fire again and it won't be the exact same position but a sort of rough area as if to suggest that what's happening is literally just when you're in a particular area a particular neuron just fires yeah and if you stay there it's firing yeah and if you go somewhere else that stops firing and another one stops firing as you've got a map you've got a map inside of your brain you can sort of if you look if you imagine all of these neurons laid out inside of the hippocampus like they're like literally laid out physically in a way that corresponds with the physical environment which i find quite incredible yeah absolutely and you can then also fool these rats because they can associate you know the left hand side of a room with this neuron firing and if you just artificially simulate that neuron they think they're on the left hand of the room yeah which is kind of cruel um and again it's it's so unfortunate that so much of this involves you know questionable treatment of animals to say the least but it does tell us something really interesting but i didn't know that we didn't have evidence of place well they haven't found them i mean yeah i guess the problem is how are you going to find them yeah so you're not i'm not letting anybody go poking around in my hippocampus and they're moving me around the room thank you very much yeah you know um so they're ethical that my guess is that we will have something similar, but that it's going to be much less developed because our ecology is very different.

2:13:42Okay. So if you're a mouse, you want to go around the edge of a room. You don't want to go around the middle, right? Humans are going to be much more, you know, you might, you're going to wander all over, even a big space, right? I mean, if you knew there were big predators around, I don't know, you'd be changing your behavior a bit, but you don't have that instinctive response of, you know, keeping to corners or whatever.

2:14:04Matthew Cobb:So the ecology is going to be what is driving brain structure because and this was darwin uh one of the you know saying the problem about function and and structure and how does it all work darwin worried about this and then he said you know i don't care i don't know how care how behavior and consciousness and all that stuff emerges from brains all i need to know is that there's a link because natural selection can affect structures it can make giraffes necks grow longer or whatever and it can affect brains because brains are just structures and if you affect a brain it's structure you change behavior and in fact the other way you can produce a particular behavior so you know okay you will be selected for if it's successful and that part of the brain may grow bigger in the next generation because you know overall the population has got more and more people with that particular size of the brain you know kind of selected for so the my suspicion would be that humans, for our particular ecology, we may not have as easily detectable a system of play cells as is the case in rodents.

2:15:14But it'd be very odd, I think, if we had no way of identifying. When you want your spring break to feel like... And your kid's pool day to feel like... And your hotel bed to feel like... Ooh, and room service to feel like. Because at Hilton, hospitality feels like. Your cabana's ready. Would you like fresh towels? It matters where you stay. Book now at Hilton.com. Hilton, for this day. This episode is brought to you by Athletic Brewing Company. No matter how you do game day, on the couch, in the crowd, or manning the snack table, Athletic Brewing fits right in. With a full lineup of non-alcoholic beer styles, you can enjoy bold flavors all game long.

2:16:05No hangovers, no buzz, no subbing out for water in the second half. Stock the fridge for tip-off with a variety of non-alcoholic craft styles available at your local grocery store or online at athleticbrewing.com. Your beer, fit for all times. Defying it. That's cool. It works in 3D space as well, like if you measure a bat. Bats do this, absolutely. Yeah, you map it onto the world, it creates sort of a sphere in the air of where those neurons would fire, which is incredible. Some people listening, I suppose, in closing here, it's very clear that we know very little still, and there's still so many questions to be answered.

2:16:42but some people might be thinking you know we've got technologies like you said i'm not going to allow someone to go poking around in my brain well why would you have to we've got these things like mri scanners i've heard of those you sort of put a big sort of magnet around your head and can't you just sort of like measure the brain activity and then you know go in an mri and then maybe like simulate the experience of moving around and just look for place cells right like it is true that these technologies have been quite revolutionary and changed a lot for us but perhaps they don't do as much as people think that they can um i think that's the case uh and

2:17:14Matthew Cobb:i'll give you two two reasons firstly there's the so there's a very big division between particular fmri between researchers who use fmri who love it and those who don't are extremely suspicious of it and the people who use it are you know all good people so i'm not you know i'm not dissing anybody here. But the system is very coarse. In particular, if you're taking the kind of approach that I'm interested in and have been arguing for a much more cellular approach, then the tiniest voxel, a three-dimensional pixel, in one of these scans contains millions and millions of neurons and even more synapses.

2:17:54Matthew Cobb:I mean, so you can't... All that these scans do is say something is happening here because they measure oxygen levels. So if the cell is active or there's millions of cells in that vox cell are active, it lights up. It doesn't actually light up, but that's what the scanner is bright because there's more oxygen in there because there's more blood flowing. That's all it is. It's metabolically active. So an fMRI scanner just measures blood flow in certain regions of the brain essentially. Yeah, the metabolic activity. And so if it's active. It didn't tell you whether those cells are on or off. And cells can be activated.

2:18:29They can be inhibited. So most sensory cells have what's called spontaneous activity. So they just kind of fire at random. If you activate them, they will often start firing very rapidly because they're excited. Some cells, if you activate them, will then turn off completely.

2:18:47Matthew Cobb:So it's not binary, right? You've got negative response. You've got zero. If you want to put it this way, you've got firing randomly, and then minus one, which is nothing there. The smell cells that I've studied in the maggot's nose, not in the human nose, they do exactly that. They will go on in all sorts of interesting ways. They will not change, or they will go off for varying durations. And all those are significant in terms of how the brain's responding. So an fMRI scan, I guess we're back to the climate change thing. That's great for telling us the big weather. Okay, there's a storm oncoming and that's pretty accurate right so we know when the hurricane is going to hit on the other hand uh it told me that it wasn't going to rain in london so i didn't bring a coat today i walked out of the station and there was water it had been raining now so the weather the localized weather forecast was hopeless but the big picture is okay yeah so it's telling you different things yeah it's like you know it's like sort of if you're staring at the empire estate building and you're sort of seeing which lights are turned on you can do that and that might be useful to some degree but it's not going to help you work out like the chemical composition of the perfume sat on a shelf in one of the rooms you know that requires a little bit more precision well you need to go in and have a look yeah yeah so this is a problem with the human brain it's very difficult to do so fmri scans uh are problematic in in in that respect and the other way I think is, and this is the most mind-bogglingly thing.

2:20:14So we talked a bit, not that much about consciousness. So defining it is hellishly difficult. There is no measure of it. So you cannot put somebody in a scanner. Let's say they're not responsive, you know, one of these locked-in syndromes where you don't know what's happening. You can't put them in a scanner and say, okay, they're conscious. We should look after them or they are not conscious. But if they're brain dead than we know but you can't tell consciousness from from all we know about consciousness is it dissolves in halothane which is what you have when you're uh you're doing

2:20:49Matthew Cobb:getting a general anesthetic yeah it knocks it out how that works we don't know so if anybody's going under the knife in the next few days don't worry because they know exactly what to do it's just that we don't understand the neural mechanisms we're getting there to understand neural mechanisms and general anesthetics. It's still a little scary, you know, because... It's not nothing, but, you know, be confident you're an anesthetist. What if it doesn't get rid of consciousness? What if it just switches off memory? Oh, don't, don't. No, this is too horrible. Okay, so this is one of the awful hypotheses, is that, yes, it doesn't work, it just paralyzes you, and that you don't remember anything.

2:21:28Yeah. I'm sure it's not like that. So you've been in agony for all that time and you don't recall it. I find that very unlikely. And also, even if that were the case, there are good philosophical reasons to think that that wouldn't matter when all is said and done. Well, it wouldn't matter to you at the time.

2:21:46Matthew Cobb:But if you didn't remember, I mean, you'd be like H.M., right? You know, you had done the experiment the day before. You had no idea. But, I mean, I don't, I hope that's not true. Quite true. Yeah. I don't think that was a very fair thing. There may be people out there who are going to be afraid to die. No, I know. That is very unfair. All I know is that everyone I've ever known who's undergone such a thing has actually found it kind of enjoyable. It's like a little experiment. Yeah, absolutely. They count and then you're out and then you wake up and you're back. Yeah, but I remember I spoke to someone on this show the other day, Bernardo Kastrup, who said when he was being an estetide, he wanted to kind of do an experiment.

2:22:20He was like, I'm going to try as hard as I can to stay awake. And so he sort of, he starts counting. He's like, you know, one, two, three. He's like, four. He goes, five. And then he says to the doctor, like, you know, is it normal for it to take this long? And they go like, oh, we're nearly done. And he's like, what? You know, it's amazing. I'd love to experience it like that.

2:22:43Matthew Cobb:Well, anesthetists, I think, get used to people thinking I can beat the system. But he didn't even, for him, it was just like a continual sort of line of experience. it was kind of terror and as a philosopher he was like the way that those two that sort of big gap you can take each end and stitch them together into a continual experience well that's i mean that's partly what perception is right so we're not perceiving reality yeah we're not it's not unmediated it feels like we got these holes in our eyes and everything's just coming and all our senses just getting this information we know that's not the case yeah there's a delay yeah There's a delay in perception, which is simply the delay in the activity of the neurons.

2:23:22Matthew Cobb:They take a few hundred milliseconds. So, something happens, you hit your foot and then you will detect it. Those cells are going to take about 150, 200 milliseconds to respond. By the time it gets up here, it's a bit longer. So, something like... I mean, Helmholtz was the first neuropsychologist to work this out in the 19th century. He said, well, wait a minute, What about whales? If I tweak the tail of a whale, when does it finally work out that something's happened? His calculation suggests it was about a second and a half. So we're living in the past. And above all, those pasts aren't going to be identical for different sensory systems, but we're making sense of stuff.

2:24:00Just like in perception, again, Helmholtz showed this, there are these people probably know about the blind spot. If you stare at it, fixate at a particular point,

2:24:08Matthew Cobb:then there's part of your visual field around here and here which there's nothing there and yet you don't feel that there's a big black hole. Your brain is just kind of, it's like Photoshop, just blurring it in. Okay, right, we'll stamp that. Okay, copy that, copy and paste. You can sense something out there. There are experiments you can do like they're famously, you know, big sort of white screen and they put a spot at the right area and if you move it to the right distance, it just disappears. Yeah, you can't see things. But even then, it's not like you suddenly, oh, now I can see the big black hole.

2:24:39It just fills in white. your brain just sort of lies to you yeah absolutely well yeah i mean what helmholtz said

2:24:45Matthew Cobb:which is incredibly smart for a guy in the 19th century is that the brain is making hypotheses about the induction inductive hypotheses it's looking at the world it works out what probably should be there and then it tells you that story most of the time that's fine you know you put yourself in a weird psychology experiment and then you can detect it but because you're moving your eyes around all the time we don't know just the and that's not the kind of thing that you can like tests well like you say you can test for the neuronal activity although i'm still not quite sure how that like an mri scanner it's magnetic right and i don't actually know how it measures the oxygen blood i imagine that's extremely complicated some kind of i don't know i'm not enough of a whatever physicist however they do it um firstly it measures only at a sort of zoomed out resolution secondly it's measuring brain activity and consciousness is correlated with that may be caused by it you know like but there's no guarantee of that and it's like the one thing in science that seems to resist measurement but my my final question for you then is i'm going to do the thing that the publisher asks you to do but hopefully with a little bit more precision and a recognition that this purely speculation do you think it ever will be able to do you think you'll ever be able to look at a brain and see consciousness yes but that i i say yes but i've recognize that is almost an article of faith.

2:26:03Matthew Cobb:It's faith not in an old book or in some old belief, but it's a faith that we got this far already. That is the scientific method and scientific approaches. We'll get there in the end, I'm confident. But just remember, physicists don't know what 90 % of the universe is made of. So we will understand that in the end, I hope. But these are massive problems that have bedeviled us for millennia. And I think all we can do, I mean, I don't think people should despair, right? And despair can take the form of going, hey man, everything's conscious. Panpsychism is one very fashionable thing, especially, you know, if you are interested in psychedelic drugs, which, you know, seem to change your perception, well, they do change your perception and understanding a reality, then you can think okay well maybe everything maybe this chair's conscious yeah but that actually is you're not explaining anything i'm not into that that's the biggest criticism of the panpsychist worldview is that it's a sort of panpsychism of the gaps yeah it's the same thing that people did with god i've had a few panpsychists on this show and i've been talking about that view and idealism a bunch and i i get a lot of flack actually for having i get excited about an idea and then i bring on a few people who talk about it and i get sort of accused of um of sort of going too hard on that worldview so it's nice to have some sort of materialists on the show as well you know i i i've made a made a conscious effort if you will to try to to try to bring a variance of people on but you know i'll i'll i'll leave i'll leave the panzaikists to speak for themselves since oh yeah i mean you know they think they could be right so my view i'm very very confident we will not in my lifetime i'm sure of that right because i mean that'll be whatever 20 30 years that's no way we're going to make a breakthrough in that kind of time scale unless something very very strange happen so it's possible you know maybe large language models can could be able to pull something out of this huge tsunami of data i mentioned maybe we'll all make it all come clear i mean certainly that's the kind of thing people are trying to do to see can these machines see patterns if we can't i still guess that that's it's we haven't got the right kind of data to be able to do that but that may well be an approach that will happen this century i mean listeners and viewers if they're still around uh you know in another 60 odd years may go haha you see we got there yeah things often come faster than you expect but it may be that it takes millennia yeah yeah i you know um i don't know what can we do just i did a panel recently with brian cox oh yeah it's first time i'd met him and uh there were some questions that were going to be on the from the audience and some of them were sort of about panpsychism and that's something he to say the least wasn't really sort of feeling it and i sort of tried to say look you know like maybe it deserves a hearing you know and i just remember saying to him like but you know it is growing in popularity this view and he said uh he said so is nigel farage is what he said in response do you know okay touche fair enough but i i like um i i understand why i think it's it's silly to ask scientists or indeed historians things like what will happen in the future because you know who knows but i love asking just on like a speculative friendly level what do you think and i i like what you said it's sort of it's not it's not faith in the books of the past it's faith in the books of the future yeah i think that's a nice way of putting it they the last paragraph is uh my attempt to sum up what might happen and it basically i mean the nobody no reviewers or nobody i've talked to has ever commented on this perhaps i haven't spoken to the right most learned people but i stole it off nietzsche so i was reading a biography of nietzsche nietzsche in one of his more crazed moments is talking about the future and the psycho the the philosophy of the future and he just because he was going a bit bonkers when he write it he just kind of spews out all these possible alternatives which is kind of what i did and partly to keep everybody on board i listed all the various approaches that are trying to understand how brains work and what consciousness might be and they're all listed and then at the end and this is what i stole from nietzsche you know it's this or this or this or this and then the last word is or dot dot dot so in other words he left it open and i just thought how astonishingly bold to finish on saying there's a you know make it up you work it out yeah you're going to find out what's happening that was partly as i said the book is not just a history it's also trying to point the way forward and part of it is a was a not a challenge but a way of talking to my neuroscience colleagues and saying well okay you know if none of this fits if all of these various options that people have got the moment aren't right then what what can you come up with yeah and we'll see we'll see the book is the idea of the brain it's of course linked in the description matthew cobb excellent thanks for your time thank you thought sweet green was just salads think again there's a new way to do sweet green.

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