BI 204 David Robbe: Your Brain Doesn't Measure Time

[00:00:04] Speaker A: How do we measure time? Well, we measure time because while we have those things changing in us, there is also regular things outside. And those regular things, they leave traces that we can use to measure time. And so that's where it's a little bit funny to think that there could be internal representation of time or internal measurement of time. What would that mean? We don't know what it means, an internal measurement of time, because measurement by definition has to be somehow related to an external or observable standard. That's why I think people are interested in version now is because this Duray is really something that is not in our computer or that is not in AI. [00:01:01] Speaker B: This is brain inspired, powered by the transmitter. When you play hide and seek, as you do on a regular basis, I'm sure, and you count to 10 before shouting, ready or not, here I come. How do you keep track of time while you're counting? Is it a clock in your brain, as many neuroscientists assume and therefore search for in their research? Or is it something else? Maybe the rhythm of your vocalization as you say, 1, 1000 to 1000. Even if you're silently counting, could it be that you're imagining the movements of speaking aloud and tracking those virtual actions? My guest today, neuroscientist David Rob. Sorry about my French, David Rob or Robbie. David believes that we don't rely on clocks in our brains or measure time internally or really that we measure time at all. Rather, our estimation of time emerges through our interactions with the world around us and or the world within us as we behave. David is group leader of the Cortical Basal Ganglia Circuits and Behavior Lab at the Institute of Mediterranean Neurobiology. His perspective on how organisms measure time will duration is the result of his own behavioral experiments with rodents. And by revisiting one of his favorite philosophers, Henri Bergson, Henry Bergson. The Americanized version. In this episode, we discuss how all of this came about. How neuroscientists have long searched for brain activity that measures or keeps track of time in brain regions like the basal ganglia, which is the brain region that David focuses on in his research. How the rodents that he studies behave in surprising ways when he asks them to estimate time intervals or durations. And how Bergson introduced the world to the notion of dure, our lived experience and feeling of time. So this conversation is particularly fun for me in that I have a philosophical bent. I'm not a philosopher, but as a scientist, I often struggle and and do so aloud on this podcast. I struggle with how Philosophy can influence, in a practical way, my own science and science more broadly. And so David's recent past is a good case study in that very phenomenon. Click below for the show Notes where I link to the paper in which David really fleshes out everything that we discuss. That paper is called Lost in Time Relocating the Perception of Duration Outside the Brain. If you value brain inspired, consider supporting it on Patreon. To get full episodes, access the full archive of episodes, join our Discord community, or just express your appreciation. Thank you to all my patrons and to the Transmitter for their support and their community work in neuroscience. @thetransmitter.org here's David. Announce your name for me so I get it right when I do the intro. [00:04:02] Speaker A: So in French, I would say David, Robin. [00:04:05] Speaker B: Rob. [00:04:05] Speaker A: Okay, that's okay. If you say Robby, it's fine. Many people say Robby and that's fine, too. [00:04:13] Speaker B: Okay. Yeah. And I'm probably going to say Henry Bergson instead of actually. So. All right, so I'm going to start here. We were just talking offline and we'll come back to it about basal ganglia, because that's a lot of what I'm doing these days. And that's what you do in what. In your. Well, historically. And in your day job. In your real job, perhaps. Although what we're going to talk about maybe is coming a little bit more into that, because they're related, essentially. [00:04:43] Speaker A: Oh, yeah, totally. Totally. And this is where it got me started in the time. In the time business was all those kind of stories in the mid-90s saying that there were potentially internal clock in the striatum that were like, yeah, providing internal representation of time. So that's what got me started from the beginning. I had a problem with this idea. That's where. [00:05:09] Speaker B: From the beginning. Okay, all right, well, let's get to that. But first I want to say, because we were talking about what I'm doing and I'm in Eric Itri's lab. I reached out to Eric and I was like, hey, you know what? Anything you want me to ask? And first of all, he said, by the way, so I need to ask you, how's the tennis game? Semi pro. How's your tennis game coming along? [00:05:27] Speaker A: It's going a bit down. I have to admit that those. Those last two years, I've been playing less. So I play less. I still do from time to time. Local competition in Marseille, and I need to go back to that more seriously. But I have to admit that I kind of like, yeah, I went A little bit down in my tennis, but it's still something that I enjoy a lot. [00:05:54] Speaker B: Sorry, this is a total aside already. I'm terrible at doing this. But did your sports, and tennis in particular, perhaps that lead you to interest in behavior and. Or timing? [00:06:07] Speaker A: So I think it's interesting you're asking that. I think at the end. So as a teenager I was a lot into sports. Tennis and football. I mean, soccer and Yeah, I went in neuroscience. And it's interesting how I'm converging more and more back to behavior. And I think he'd asked something related to. To my. Yeah, my passion for sport and movement. So it's interesting that I started by doing, you know, slice electrophysiology. Then I went to the postdoc in Yuri's lab with, you know, in vivo in behavior recording. And now I'm doing less and less physiology and more and more behavior. [00:06:49] Speaker B: So why is that? Is that because we, for me, I've become more. More interested in behavior. And really what I'm interested in is, you know, the connection between neural activity and behavior. But the more I learn, the more I know how. How little we know about even the neural side of it. And then I guess my framework for thinking about these things has changed. And behavior itself is an open question and neural activity is an open question. So you and. And of course, I'm just preaching to the modern neuro behavior choir that you have to study these things. We're embodied and you have to study them in conjunction. [00:07:27] Speaker A: So yeah, yeah, no, I think it's a combination of things. But it's true that my experience has been that it's really important. I mean, like, behavior can explain so many things just by itself in the way when you do electrophysiology in vivo. So if your behavior changes, your neuron activities change. Okay. So that's the first thing I learned with Yuri Bujaki. And that was really great. And so I really enjoyed actually watching rats running in a maze and seeing actually how you could almost anticipate if it was going to do right or wrong just by looking at the way rats were running. So I got really into behavior and then I read and I had the chance to met another one of the regular guests from this podcast, John Krakauer, who really also like pushed me and like kind of like kept like telling me no. But that's actually you have to go. You have to be very careful with behavior. And also some, yes. Some personal experience how it is easy to actually, you know, when you do. If is in. Behaving animal, it's so easy to basically have a sort of bias that is going to make you interpret the data the way you want to interpret them. Because it's. So I realized couple of times in my career that I was very close to make mistakes. And then I thought, yeah, we need to. The key is we need to understand really well what the animal is doing. Otherwise we can tell basically almost whatever we want. Especially when you record in a place like the striatum in which you have a very heterogeneous kind of type of response. So that has been the trajectory on those years, like really trying to understand, well, behavior also practically. I mean, chronic electrophysiology in behaving mice is really, really hard if you want to do it right. And in France it's tricky. We have very short. The funding is Limited, the PhD duration is short. So it's tricky to have a project that really, you know, that you manage to go through a PhD in which you do, you know, good behavior, good electrophies, good data analysis is just impossible. So I ended up. But I hope to do more electrophysiology soon again. But I ended up doing a lot of behavior also because it's already a lot of work. But you can make a story in like three, four years if you do good behavior and a bit of perturbation, I think. [00:10:13] Speaker B: Yeah, I was going to say. I mean, that's why we come in with. We have to be careful because we come in with. I guess the technical term would be bias. But we have a story about what we're looking for and by God, we're going to find it or something related to it. [00:10:25] Speaker A: Exactly. [00:10:27] Speaker B: Who is Henry? Sorry, I'm going to say Henry Bergson. Henri Bergson. You say the name again. [00:10:32] Speaker A: Henri Bergson. [00:10:34] Speaker B: There you go. I'm just going to butcher it the whole time. Who is this historical philosopher, slash scientist, slash mathematician? Sort of. And why are you so obsessed with this person and his ideas? [00:10:48] Speaker A: Yeah, so, so, so he's not a scientist now. He's really a philosopher. Yeah, so he's a philosopher of. I think he's born in 1859 or something like this. And he died in 1941. [00:11:01] Speaker B: 41, I think it's 41, yeah. [00:11:06] Speaker A: So yes, he's a. He's a. He's a French philosopher that was actually extremely famous at some point. He write couple of important books. [00:11:15] Speaker B: He was a celebrity in his day. [00:11:17] Speaker A: He was a celebrity. So right now he's a lot in the light after being in the shadow for a while. He's been more recently a lot in the light. There's a recent biography in English that has been published by Emily Herring. [00:11:30] Speaker B: Oh, okay. But I just want to stop you because I can never tell these days, especially with, you know, the algorithms that feed you what you're sort of have been searching for and just kind of you get in that silo. Is he kind of making a comeback? [00:11:45] Speaker A: I think he is. [00:11:46] Speaker B: Or is it just me that I'm seeing more of it? [00:11:48] Speaker A: No, he's making a comeback, but it's not just like since last year or two years ago. I think it's more like something. Let's say that I started growing maybe 10, 15 years ago and now it's starting to really. So first it was like more something local also evidently a lot in France. But now I think it's becoming bigger. And my idea is, because he's a. I think you could define him as really a philosopher of the living. All right. It was really about understanding the difference between, yeah, what's so special about living organism versus, you know, other non living things or other. The movement of non living things. So that was his biggest. His big things. And he tackled this question at different level. You know, the level of the perception of time, then of memory, and then evolution. His big famous book is Creative Evolution 1907, for which he got the Nobel Prize of Literature, which is a paper that has a book that has been. So he's been very misunderstood. Bergson, because he's. He's kind of is a philosopher that tends to say, well, there is some limits to science. And so scientists didn't like so much this idea. So he went, you know, he's famous also for a famous debate with Einstein, but so he challenged some of the ideas of Darwin in terms of the mechanism behind evolution. He was a true believer in evolution, but he was not sure about the mechanism that allows animal to species to evolve. And because he had this kind of view that was not mechanistic, he got kind of like, you know, he got some like pushed strong pushback when all the genetics movement came strong in the middle of the century. And so it got a little bit, yeah, kind of like push aside also. He had a very special way of doing philosophy. He didn't really build the school, so he got quickly forgotten. But the truth is that if you read his book, it's really deep. So I think what is nice is to see how somebody at some moment can be kind of like forgotten and then come back and sound so modern. When you read Bercen, that's really what strikes me is how in so many instances it's like he's just talking about the stuff we're dealing now. So that's really cool. [00:14:28] Speaker B: Why is that? That is always the case. Like sometimes I think that an academic's job, it seems, whatever history, philosophy, science is just to point out who had that idea beforehand, you know, because it's all, well, like Bijaki says, there's nothing new under the sun. It's all of these ideas, right. Have been well traversed by sometimes forgotten people. [00:14:53] Speaker A: Yeah, it's true, it's true. But yeah, but I'm sometimes. So I have debates with some friends. I feel like Berkson did something very new, but it's difficult because, yeah, he was building. Now that I'm starting digging a little bit more and I get some help from some philosopher friends, I realized that he himself also was influenced by even lesser known people. So it's very interesting to see this dynamic. [00:15:21] Speaker B: The other comment I was going to make is I was recently at a kind of at a gathering at Carnegie Mellon University in Pitt for someone who was a mentor of mine and many of us who just recently passed. And I asked the question at our little gathering, like, so the thing is he did very careful, super sharp guy, very careful. Science wasn't concerned with glossy journals, just concerned mostly like with just doing, asking the right questions, pursuing it the right way. And you know, he's got a great publication record. And I asked like, you know, what do you think his legacy is going to be? And it's an interesting thing. What I kind of imagine is 40 years from now, people are going to look back on some of these papers, right. And dig them up again. And in the meantime, he might be kind of forgotten. I don't. It's hard to tell. [00:16:14] Speaker A: But yeah, but yeah, yeah, maybe also the people that he talked to will actually, you know, he will probably have affected the life of a significant amount of people that are going to do science in a different way because of working with him. So I think even like Berkson, even when he was kind of like forgotten, he was still very influential. But just people didn't want to mention his name because he was Persona non grata. But he was still very influencing people. So that's why I think, yeah, well. [00:16:44] Speaker B: From what I understand too, that he is maybe at least popularly most well known for losing that famous debate with Einstein. But then a lot of careful historians have looked back and it's a lot more nuanced. He didn't just lose a Debate. They misunderstood each other. They called each other out in their misunderstandings. And so it's not clear who, quote, unquote, won or lost. [00:17:07] Speaker A: Yeah, no, yeah, clearly he was perceived as the loser. I mean, he was tough not to lose again. Einstein. No, I mean, I remember myself now. I remember when I was a student, I had a poster of Einstein in my room in the university. I had no clue. I had no understanding about the theory of relativity. [00:17:31] Speaker B: Of course not. He was just a figure, an idol. [00:17:33] Speaker A: So, yeah, there was something so big about him, nobody could really win against this guy. But it's true. You're right. Like, what people. So a couple of people have done some work. Ximena Canales, I think, is the one that wrote this book. This. The philosopher and the scientist. [00:17:49] Speaker B: And the philosopher and scientist. [00:17:50] Speaker A: Yeah, exactly. [00:17:51] Speaker B: I think that's right. [00:17:52] Speaker A: So in which she. She shows that, yeah, there was actually no. No real debate. They misunderstood you. You quote. You said it right. Another French philosopher is doing. I think there's a book that is going to come out soon. About. About. About. About it. Yeah, I think actually. So I would side with Berkson in the sense that. So you have to read. So he wrote a book. [00:18:17] Speaker B: Wait, but you should say what the debate was about. What you're going to side. What? [00:18:21] Speaker A: Yeah, yeah, no, the debate was that. So a sort of like implication of the theory of relativity was that maybe there would be some kind of like multiple temporality. There was no more. This unitary Newtonian time was basically gone. And Bergson said, well, your finding is basically about things that move extremely fast, very close to the speed of light. But we can still wonder if, in terms of our experience of time, if we should completely challenge this idea that we more or less all of us, you and me right now, are living on the same temple. Okay. So that was the debate. And what's kind of impressive is like, so he wrote a book about it which goes. Called Dure and simultaneity. So duration and simultaneity. And if you open the book, the first. So the beginning of the book is him actually rewriting the equation of the theory of relativity and saying that he entirely agree with the theory. So he was a guy that was able to actually redo the math, which me, I'm not able. People say it's not that complicated. But he did this effort. So he did a huge effort. And actually he called himself really, that is more Einsteinian than Einstein. But his question was, can we make conclusion about our experience of time based on a theory that is Applied to things that move at the speed of light or very near the speed of light. And that was his question. And to the discredit of Einstein. Einstein did not make a lot of effort, if you would kind of balance the two. If one guy had made a lot of effort to understand the theory was more. But the problem is that Bergson is a bit. Is not always easy to understand. So his weakness is that he didn't manage to make himself understood from Einstein. And Einstein was not very patient. [00:20:39] Speaker B: So he also Bergson people back in the day, and this is the story that is kind of now becoming overturned, is that, well, he wasn't good at understanding the science, but he actually was good at understanding the science. Everything that you saw. [00:20:52] Speaker A: Oh, yeah, he was good. He was very good. He was an extremely bright guy. He had, like. Yeah, he had, like, one lots of prices in mathematics when he was 18, 19, 20. And his teacher were extremely disappointed that he decided to do philosophy. They were like, come on, you should be a bright mathematician and you're going to end up just like a philosopher. There's like a say like this that goes in the legend of Henri Berson. [00:21:17] Speaker B: Oh, poor philosophy. Why does it have such a bad rap? Because I was gonna. I was gonna ask how you got wrapped up in all this. Because I have a philosophical bent. And then there's some, you know, something behind me always saying, like, oh, you should stick to the science people. People are gonna make fun of you. But, you know, don't waste your breath on philosophy. [00:21:35] Speaker A: Yeah, well, so me, I. I think I always liked philosophy. So I. Even if I. I'm not sure, I was really good at it. And I was. I was very interested. Like, almost everyone that does neuroscience is interested in, you know, the relationship between mind and body, which was philosophy for. [00:21:54] Speaker B: A long, long time and still is. [00:21:55] Speaker A: Yeah, yeah. But I was studying biology and I was starting to study neuroscience, and I felt like neuroscience was really the key to, you know, as a student, I was like, okay, neuroscience is explaining all this. Great. And one day I was in a library, and I saw. Really by chance, I saw a book of Berkson, which is called Matter and Memory. And the subtitle of the book is an essay about the relationship between L'esprit et la matiere. So the spirit and the mind and the matter and the body, something like this. And I was like, oh, wow. This is exactly what I'm trying to understand with this neuroscience stuff. So I took the boot and I started reading. And it was kind of a shock, like, I didn't understand anything that guy was saying. He was basically saying on every topic the opposite that what I was thinking. But you could see that the guy had thought a lot about it and he was very confident and he was like, it's impossible that the brain is an organ that generates representation. And I was like, what? What are you talking about? Or it doesn't make any sense to think that the brain stores memory. I was like, what? The guy is totally nuts. But so I didn't go through the entire book, but I got one thing at that time, which is in the first chapter of this book, is that perception is a beginning of action. So that's the first part of that book. And I found that even if it took me a long time to understand this idea, at the end I was like, yes, it's true. We only perceive things we're going to be able to act on. That's not a bad point. So he had this really this loop. The fact that we're not information processing machine, but we are constantly. What we see around us is basically already kind of like adapted to our motor system. So a perception is basically a question asked to my motor system. And I found this idea very nice. The rest of the book I couldn't deal with it. It was too hard. [00:23:58] Speaker B: Pretty. This is pre ecological psychology, right? Gibsonian? [00:24:01] Speaker A: Yes, this is pre ecological psychology, which is something that then got me into ecological psychology later on. And I was like, but how come they never cite Berkshire? I was very surprised. [00:24:11] Speaker B: I was about to ask you why. [00:24:13] Speaker A: Why is that? It's very surprising. [00:24:15] Speaker B: You can. Yeah, yeah. I mean there are trails because. [00:24:18] Speaker A: Because Berkson was, I think, Labelle with this idea of Helen Vital which came later. Yes, he was labella some kind of like esoteric, kind of like romantic guy. [00:24:29] Speaker B: What is for the listeners. [00:24:31] Speaker A: So the Helaan Vital is a sort of metaphor that Bergson brings in his third book, which is Creative Evolution. And it's not. You really have to understand it as a metaphor. It's the idea that he's trying to think. So he's basically persuaded that that living. There's something different between living and non living matter and that that should be some kind of original impulse is not believing in some kind of like fluid, you know, like. So he's not a Vitalist. Right. [00:25:07] Speaker B: Which is that. That's what it got labeled as, is there's some sort of magic. But he's not dust. [00:25:10] Speaker A: Yeah, he's not. He's a scientist. He believes that the body is driven by, you know, electricity, chemistry, etc. But that at the beginning of life, there is some kind of like impulse impetus that is like sort of force that is pushing living to thrive and survive and also transform itself, etc. [00:25:35] Speaker B: And create. Yeah, transform itself and create. [00:25:38] Speaker A: And create. And create against matter. Okay. That's the big thing is create. It's a form of creation. While matter is kind of like, you know, it's kind of like trying to kind of like kill you or oppress you. [00:25:55] Speaker B: Yeah. Going against entropy despite matter. [00:25:58] Speaker A: Exactly. [00:25:58] Speaker B: Able to create. [00:25:59] Speaker A: Exactly, exactly. So he had this metaphor of Elaine Vital, and that got him kind of like smashed by scientists. Also, other philosopher Bertrand Russell was really against him. So. Yeah, so that's a bit the story. So. But yeah, so that got me into Berkson, and then I kind of like, you know, I was reading from time to time article of him, but I never actually, at that moment, I never understood the concept of duret. [00:26:26] Speaker B: So that's what we're. That's what you're onto with this paper that we're going to frame our discussion around. And so when did you pick up the concept of dure? Was it after your neuroscience beginnings? And. [00:26:40] Speaker A: Yeah, yeah, so that was way after. So actually what happened is that. So. So we were interested in the lab. So there was a lot of those hypotheses saying that they were like kind of like really time representation in the striatum. But everybody knows also that the striatum is really important in motor control. So I had this idea, and others too, that probably if the striatum had a role in like, time estimation, it was because it had a role in motor control. [00:27:11] Speaker B: Well, and we should say, like, that this idea of there being time represented internally, it's been applied to many parts of the brain. It can be decoded from many parts of the brain. And so it's been ascribed to. So the assumption is we must have this because we're good at timing things. We must have these internal clocks that our brain produces that we can then read out as organisms to do things. [00:27:36] Speaker A: Right, exactly. But at the time where I started working on this, the striatum was one of like the big kind of like, okay, there were striatum and prefrontal cortex and cerebellum were kind of like the three things, the three kind of like hotspots for time at different timescale. So we wanted to. So my idea was that actually the role of the striatum in timing was related to movement and that it's because it changed animal move that that animal changed their performance in time estimation tasks. So with actually, my first postdoc, we designed this crazy experiment. Pavel of Hueda Roscoe, who's now in Mexico, we designed a task on a treadmill. So we knew. Another thing that everybody knows, but nobody speaks too much, is that if you do a time estimation task in which you request the animal to really respect a time interval, otherwise he will get like a, you know, no reward or a punishment, then animals develop those kind of, like, weird superstitious behavior. So this was something that was known. Okay. And this was the problem that we had also, is that we know that the striatum responds to movement, to sensory stimuli. So the trick is that how do you make an experiment in which you can dissociate time and movement and sensory response, knowing that on top of that, the animals are going to tend to develop some kind of motor, routine, superstitious behavior? So we decided to do a time estimation while rats would be running on a treadmill. Okay. The idea would be to kind of clamp the animal into a state in which it cannot really escape. And what we wanted to do is that we wanted to change the speed of the treadmill. And our expectation would be that if the treadmill goes faster, maybe the animal maybe counts with his paw. And so then he would have the impression that time is passing faster. Something like this. This was kind of our intuition. Okay. And then we got this very weird behavior. So the task was, you know, we had a treadmill, and the animal had to go at the front of the treadmill. There was, like, a reward area that was clearly salient. And the task was the animal has to go there seven seconds after the trial started and the treadmill start pushing the animal away from this reward area. [00:30:02] Speaker B: So. So if the animal is still, it starts moving back on the treadmill. And the. But what you guys thought was that it would just kind of keep running right next to the reward port and just time it for seven seconds. [00:30:12] Speaker A: Yeah, exactly. And they didn't do that. They all. All the rats starting doing this strategy in which they. They so through first they struggled. Okay. Because they would go too early. Okay. They would go too early. So they would go early, get like, you know, beep, a sound. Then we had like a sort of a. We had the rat run for an extra time. So. Yeah, so. So they did a lot of error trials. Because the impulse of a rat like us is if he's thirsty and there's a reward in front of him, he goes there straight. Okay. [00:30:44] Speaker B: Yeah. [00:30:45] Speaker A: So he does that over and over until he gets bored. And then a new trial starts. The treadmill pushes the animal away and then at the end, the animal bump into the rear wall and then run. And then he gets the reward because now seven seconds. So we had a time of seven seconds. Seven seconds has elapsed and he gets the reward so that the animal understand that to get the reward they have to go to the back and then. [00:31:15] Speaker B: That'S what their superstition understands. [00:31:17] Speaker A: Yeah, exactly. So we were really disappointed because this is not what we wanted. And we tried a bunch of stuff and it never worked. But we said, okay, this is great. We have a nice stereotype behavior. We can do recording in the striatum, which is supposed to be important in stereotype behavior. And we did still a very nice paper on this with Pavel. But then we had the visit of John in the lab and John told us, you guys need to understand better this task, what the animal is doing, et cetera. So we did a lot of experiments and we realized that really the animals were unable to do this task if they were not allowed to use what we call a motor routine. [00:31:58] Speaker B: Yeah, but did they all develop slightly different routines or was it. [00:32:02] Speaker A: So in our case like 80% of the rats developed this routine. But I think it's because of the setup. We had some rats that were doing other stuff, but they were still doing some stereotype stuff. [00:32:14] Speaker B: Yeah, still stereotyped, but it wasn't always just hit the back wall and then go and run. [00:32:19] Speaker A: But this is the easiest one, basically. So I think this is why many rats stumble onto this one. [00:32:27] Speaker B: Wait, let me just pause here and just say because this experimental setup is sort of in between, the hyper reduced experimental setup that had become dominant in neuroscience and was still, you know, that's my PhD work was fix everything as still as possible. The organism needs to move only its eyes right. To perform this task. And of course the animal wasn't completely still. Of course they had their, they were moving their arm, you know, even if their head was fixed or whatever. And so they still. Your point in the paper also is that all of these hyper reduced experiments, the animal people don't control for these little movement routines that the animal could be undergoing to help time behaviors in these timing tasks, for example. But, but so yours is in between. So that's the hyper reduced. And now we have like these super freely behaving and I guess yours. Those rats were freely behaving on the treadmill. [00:33:23] Speaker A: Yeah, it was freely moving. [00:33:24] Speaker B: Yeah, yeah, but they're still in the Behavioral like they're in an apparatus, right, that they're behaving within that context. [00:33:31] Speaker A: And our idea was to somehow try to clamp this motor activity, and we failed because. [00:33:39] Speaker B: Clamp it while they're behaving freely. [00:33:41] Speaker A: Exactly. And so, yeah, so we did a kind of a nice purely behavioral study in which we did a bunch of manipulation to see that, yeah, like, it was really the routine that the animal had no clue, really, about time. They really managed to do this task by developing a motor sequence. And if you perturb this motor sequence, then the accuracy goes down. And we were wondering, and some people told, you know, we had the debate, why is this this way? Or is there other condition in which the animal could do a time estimation task? Is this just like a failure to basically be understood by the animal, etc. And this is where I stumble again, by chance, on Berson. Actually, it was just at the beginning of the COVID. [00:34:33] Speaker B: When you're going through your old books and saying, what shall I do now? [00:34:38] Speaker A: Actually, more luckily, there was a podcast in France about matter and memory. And so there is this really cool philosophy podcast that does not exist anymore called the Chemin de la Philosophy, the Road of the Philosophy. And they had a podcast in four episodes, the four chapter of Matter and Memory. And so I'm like, okay, you know, I have time now. I'm going to listen to that. And the first podcast, the speaker is like one of the most famous scholars of Berson in France. Frederic Worms is his name. And he says, well, we have to understand that the matter and memory the book is the problem comes from actually the first book of Bergson we see, which is Time and Free Will in English. And in that book, Bergson says that we misunderstand time because instead of leaving it, we specialize it. And then what was very interesting for me is that the conclusion of our papers, so a paper that we published in PNice in 2020 was that rats were developing. Were developing a special routine to be proficient into a time estimation task. So that was like the conclusion that they were specializing time. And I was like, what? Like, it's exactly what our rats are doing. [00:35:57] Speaker B: Wait, you wrote this before you came across the. [00:36:00] Speaker A: Yeah, yeah. The 2020 paper was written. I hadn't been back to Berson. And then. So then I was like, oh, I need to read this first book. And then it was really kind of a sort of like, you know, like a sort of deep eureka kind of moment. [00:36:15] Speaker B: That is the best when you revisit, although you weren't Revisiting in this case. But you were revisiting Bergson. But you weren't revisiting. But when you. What my point is when you read something even that you've read before, but you're coming at it from a different framework, you get. All of a sudden, it expands and you have this eureka moment. It's so beautiful. [00:36:30] Speaker A: Yeah, it was like wabe. Yeah, he's explaining us exactly why animals do that and why they actually can't do a time estimation. And so that was like, you know, I felt very like. [00:36:43] Speaker B: Right, right. They can. [00:36:45] Speaker A: They can't do it internally. And actually what they're doing is just. They're getting rewards. They're not really measuring time. They're just, you know, they're just doing what we want us to do, which is getting. [00:36:57] Speaker B: This is where your utility comes in, that they're actually basing their. [00:37:01] Speaker A: Yeah, that's. That. That came. That came a little bit later, but also with a bit thanks to Bergson, because he has some idea about time being like a sort of cost, you know, and actually there is a huge field in neuroscience about this idea about time being seen as a cost. So, yes, this was my moment in which, like, so. And it was great because this was the COVID lockdown. So I, you know, I read. I read this book. Then I understood better Matter and Memory, so I read Matter and Memory. Then I read. So I basically read, like in circle, his three main books. And then I decided to write this kind of like, long piece. And it was great. It was fun. [00:37:43] Speaker B: So with his concepts, then you were able to sort of reinterpret your own data, your own studies. I don't want to lose the listener. So you should talk about what Durer is, and in Berksonian terms. Right, yeah. [00:38:01] Speaker A: So the idea of Durer is simply that when we experience time, when we live because we have memory, our memory constantly prolong the past into the present. That's the way that we manage to have a conversation together, is that we constantly remembering a little bit of the past into the present. Okay. [00:38:26] Speaker B: So every present moment is inundated with at least some of our past memories, the entirety of our past, but maybe substantially some of our memories. Yeah. So every given moment is created anew and is unique in that sense. [00:38:41] Speaker A: Exactly. So his point is that this thing is really. It's a sort of continuous, heterogeneous new thing that is created at every moment. So it's indivisible. You cannot divide it. You can divide it artificially, but the. [00:38:59] Speaker B: Duration of time itself, that experience, it. [00:39:04] Speaker A: Doesn'T make any sense to divide or the way. The example I like to use is when you grow impatient. Think about whatever occasion in which you grow impatient. It's something that accumulates, but you cannot really tell at which moment you know, you are impatient. It's just. It's a process, you know, it grows. And you cannot switch. You know, you cannot switch time to be very impatient and mad and ready to yell at somebody. You needed to go through the process of waiting. But you cannot go from mad to super. [00:39:44] Speaker B: Some people can. Some people, some very special people seem to be able to. But I take your point. But how is that related then to. How is that concept then related to externalizing time? And how do you. Yeah, so. [00:39:57] Speaker A: So his point is that. So this experience. So basically experiencing time being in time. Because you cannot divide it. You cannot measure it directly. So then how do we measure time? Well, we measure time because while we have those things changing in us. There is also regular things outside. And those regular things, they leave traces that we can use to measure time. So, for instance, the movement of a clock while I'm talking, it's moving. Then it arrives there. And then the distance traveled from the moment I started talking or moving to the end. That gives me a proxy from time. So actually, measured time is not about time. It's about space. So that's his big, kind of like discovery is to say, hey, there is two aspects of time. One that is lived in which, because of memory, it's a sort of continuous melting pot of the past, of the present. And you cannot be divided. You cannot measure it. Because one moment it's here and then after that it's gone. So there's no possibility of measurement. Because measurement is about superposition. [00:41:08] Speaker B: But in that case, isn't there no time? Because it's always just present. [00:41:13] Speaker A: So it's not exactly just present because you remember. [00:41:17] Speaker B: Yeah, but that's part of the present, right? So it's kind of growing. [00:41:20] Speaker A: But it's growing in you, you know, Otherwise you wouldn't be. You wouldn't become impatient. Something has to stay and accumulate for you to become impatient. [00:41:29] Speaker B: So it's ever changing that. That's how you. That's how you measure it is because it's ever changing in the principle you can. [00:41:35] Speaker A: That it's ever changing with this communication of the past into the present. I think that's really the key. Something. Some people mistake the philosophy, the Durer of Berson with the, say, of Heraclitus that says, you know, Everything is changing. You know, you never step twice. That's not the same idea. [00:41:56] Speaker B: I'll say Heraclitus for our American artist. [00:41:59] Speaker A: Yeah, sorry. [00:42:00] Speaker B: That's okay. Just want to make sure. [00:42:02] Speaker A: Yeah, exactly. So that's not the same idea because for him, for Heraclitus, it's continuous change all the time, but there is no memory. Kind of like effect, you see? And that's the key thing of Bergson. He's saying that each new moment, each new moment is totally new. It's not just different, it cannot repeat in the sense of, like, Heraclitus is more like a sort of eternalist kind of philosophy is changing all the time, but it's kind of the same interchange. While for Berkson is it's actually new. It's really new something. Right now, we're different. You can't measure it. It's not something like. So this. This. You cannot measure it directly. [00:42:45] Speaker B: I love this idea because, you know, as a scientist and you become a reductionist, and then you view everything in those terms, and then you think, wow, how. How does anything move? How is anything new? And I love this account of everything is always new and it is an act of creation. [00:43:02] Speaker A: Exactly. [00:43:03] Speaker B: Wonderful thing. [00:43:04] Speaker A: Yeah. So the point is that you need to be able to measure. You need to relate to something external, that you can leave fixed traces. So that's why movement is a very change. The. The change of light is a good cue for knowing how much time is passing, etc. And this is why we keep saying all the time, oh, this movie was too long or the time passed too quickly. It's all spatialized time. So we have no way to actually not measure time in reference to space and movement. And so that's where it's a little bit funny to think that there could be internal representation of time or internal measurement of time. What would that mean? We don't know what it means, an internal measurement of time, because measurement, by definition, has to be somehow related to an external or observable standard. [00:44:11] Speaker B: It's a relational relation. You have to measure it. Yeah. So in other words. Well, you have to read it out. But people like Dean Buonamano, who was on my podcast a long time ago, and lots of other people, you know, are just continue to try to find this internal representation of time, be it in the recurrent dynamics of recurrent neural networks, be it in the timing of nested oscillations in the brain that. Where you could read these things out, accumulation models, all sorts of ways that you could represent Time internally. [00:44:45] Speaker A: So you can use them to represent time for you. So you know, you plot your firing rate changes and then gives you to you a representation of time, because it's a change, but it doesn't mean that the animal use it as a representation of time. Like this was the point in which I agree with, actually Yuri Boujacki had like a very similar idea that it's not because you have like a change in your brain and then you relate it to something that it means that this is a correlate of this thing. So it doesn't have to be that way. [00:45:21] Speaker B: Since you mentioned Yuris and you did a postdoc with him in your paper, I'll just go ahead and ask this now, even though it's a bit of an aside, there's like just one or two lines and they almost seem like extra thrown in where you say, well this is where Bujaki got it wrong in his inside out view. And this comes at the end of the paper. Right. So you've built up all these ideas and then it's like you're reflecting a little bit. And at the time I didn't know that you had been a postdoc in his lab. When I read the paper. [00:45:49] Speaker A: Yeah, yeah. So I. Well, first I want to say that I'm a big, I'm a huge fan of Yuri. It was the best time of my life in his lab, really. He's fantastic. What fantastic person, human person, and a fantastic scientist. Well, Yuri has his view, you know, very like, you know, internal model. [00:46:07] Speaker B: And so, yeah, I'll summarize Yuri's view real quick. The inside out approach, right. Is the very, very shortened version, is that he thinks that we've gotten it wrong using we have these like really old psychological terms that were invented by psychologists to describe what we were doing. And then we've been looking for neural activity and processes to map onto those terms and concepts. And what he proposes is instead let's look at the way the brain is actually processing signals, information, the past, the capacities, the structures, et cetera, what the brain is doing, and then use those to build up our psychological constructs, throw away the old psychological terms, maybe come up with new ones, or understand them in a different way. And so that's his quote unquote, inside out approach, saying that we haven't gotten very far with this outside in approach. So I just wanted to make sure we explained what his view was. [00:47:03] Speaker A: Yeah, you explained that. That's exactly right. And that's exactly the point. So the point in Which I kind of like disagree with him. I think it's a false problem to say that the psychological terms are kind of like old fashioned and they don't reflect anything. Right. I think so. I think the. Again, so if you think about an experience of time. So I'll take an analogy to try to convey what I want to say. You went to a movie, you know, you had a great time, you were very entertained, and then, you know, the movie finishes, you realize it lasted two hours and a half and you say you didn't. Say you didn't see the time passing. Okay, so this is when you say you didn't see time passing. It's a very approximate description of what you experience during the movie. But it's good for communication purpose. Okay. That allows to convey to your friend, wife, partner that you enjoy the movie and that you didn't see time passing. And so that's it. It's like, it's a short, you know, it's an approximate label for the entire experience. [00:48:11] Speaker B: Yeah, it's a, it's a condensed abstract version of what you went through. [00:48:14] Speaker A: Exactly. But it's. You already, you already lost a lot of information there. But there's no way you're gonna be able to recreate all this information. Even with like, if you had like recordings, all your brain activity during the entire movie. [00:48:26] Speaker B: Right. You wouldn't, you wouldn't say at this, at this point, it was fanning in and fanning out from my retina to the, through the thalamus. And then it really fanned in and then it really. There's a lot of gain from the basal ganglion. So. Yeah, you wouldn't go through all the brain activity. [00:48:40] Speaker A: Yeah. So the point I'm just making is that, yeah, we're never going to be able to explain some aspect of our psychology because we always limited by, let's say, language. And that's fine, that language is inaccurate. Because that's not the purpose. The purpose is not to be perfectly accurate. It's just, it allows just to communicate enough. And so I don't think. Yeah, I think it's kind of a lost cause to try to find like the perfect description of like whatever brain, cognitive stuff is going on in your brain with neuronal activity. Because anyway, and I think at the end this was the point because you invited John to ask questions. [00:49:26] Speaker B: No, I think John asked the question. It was Yuri and David Poppel on the. [00:49:30] Speaker A: Yeah, but I think. Or maybe David asked that question or John or whatever one of them asked Yuri. But. Okay, now you're gonna have like, you're still gonna need at some point a word to describe the thing that relates to your, to this neuronal activity that you found was important. And so, so then you're basically, you know, and it's still going to be, there's still going to be a gap. So, so you can't really. Yeah, you can't just bank everything on the inside. There's always going to be an inside and an outside. I think. Yes, that's the way I understood. [00:50:12] Speaker B: Yeah. [00:50:13] Speaker A: Yeah. [00:50:13] Speaker B: I mean, I get behind that, but I, I've become a radical, plural, pluralist man like that. So, you know, it's not about the word itself. It's about refining the concepts that the word is attached to and stands in for. Right. And so Yuri's point, I don't want to speak for him, is that the, the folk psychological terms that we use are attached. The way we understand them might be highly inaccurate relative to the actual processes going on. So it's not about whether you have a word or don't, it's just about refining the concepts. But I don't know if he would say that at all. [00:50:47] Speaker A: Yeah, so my, my point would be that whatever concept will come out will always be somehow insufficient for two reasons. Because this is just something that is fixed. It's going to be a fixed label and our brain state is constantly changing all the time. So there will always be a kind of like a distance between the two. And that's fine. It doesn't mean that they're not related. It doesn't mean that science doesn't do a good job approximating, you know, attention, depression, feeling warm, cold or impatient, etc. So it doesn't mean that science cannot do stuff on that. But it's, there's always going to be a sort of like a little gap. And I think that's, I think it's a good news, but it's weird. [00:51:39] Speaker B: Like when. So neuroscientists do this all the time. We'll take a. And I'm sorry, I want to come back to, to the main topic here, but so using a term like in decision making sciences, Right. And in neuroeconomics, which you are right about and study, there's a term, let's say you're making a decision and then you use the term urgency. Right. But then you define it sort of neuronally, you have an operational definition. Well, actually sometimes you don't. So for urgency, then you ask, well, what would urgency look like in neuronal signals? So the other way to do it is to say, here's a neuronal signal. What concept could we ascribe to that neuronal signal? And then it's something like, kind of like what we think of as urgency. So it's coming from the bottom up. I don't want to anyway. [00:52:25] Speaker A: Yeah, but you could also try to define it behaviorally. [00:52:31] Speaker B: Sure. [00:52:32] Speaker A: And then manipulate that. Manipulate urgency, even if it's not a perfect term. But you could, once you decide what is urgency, which I think you know, it's. You can, you know, operationalize the definition, manipulate the parameters and see if it correlates with something more or less in the brain. [00:52:50] Speaker B: And then that's as long as you attach it with that operational definition. Because what happens is that then just the term urgency starts getting used to not, not be attached to the operational definition, but with our common conception of urgency. Right. And all the subjective baggage that comes with it. [00:53:07] Speaker A: Yeah. And the issue would, would also be that you would reduce urgency to the neuronal activity, which. There is no reason to do that. Because if you, you have definite. If your definition of urgency is about a certain type of behavioral attitude in certain circumstances, then it's really urgency. Is this all complex things? It doesn't have to be. [00:53:30] Speaker B: It's not that the neurons aren't urgent, aren't feeling urgency. [00:53:33] Speaker A: Exactly, exactly. I think the big issue comes with when you want to really localize things in the brain. Like, you know, if you want to say memory, procedural memories in the striatum, you know, whatever other form of memory, emotional memory is in the amygdala, then you get in all kind of trouble. And I think it's also a bit in reaction to this kind of like reductionism that Yuri also writes. I'm not sure is it right to start from the brain? I think there is no reason to do that. I think we can do both. [00:54:06] Speaker B: That's. I think that. I think you hit the hammer, the nail on. The hammer on the nail with, with the. Both. And I just, I think it's so healthy to have someone like Yuri and have people like David Popol and John Krakauer, everyone saying they've got it wrong when everyone's right in. It's both and it's all right in some sense. But bring us back to the reason that you felt. Not the reason you felt obliged to, but what you were keying in on when you mentioned Yuri's inside out view with respect to the conception of Duray and the way that you think of time related to brains and bodies and movements. [00:54:45] Speaker A: So why did I bring him in the. In the. [00:54:48] Speaker B: Yeah. What was it? What is it specifically about that approach? I think you mentioned it earlier, but maybe just restated. [00:54:57] Speaker A: It's just that basically the point of Berkson is that is to really realize that our mental state, our life, is constantly. We beings becoming. We're constantly transforming ourselves. So having some kind of fixed label is great. I'm called David, you're called Paul, and that's very convenient. It's fixed label also. We are constantly changing, and I think there is nothing wrong on that. And so what I was kind of like calling into question is that it's not a big deal that we use fixed labels as long as we are aware that they are just labels. The problem is that if we think that those labels become like, like real things that we can find, like traces in the brain, then that doesn't make any sense. I don't know if I'm clear, but it's like, okay, now if you think attention is one thing, you're going to want to find attention in the brain. And that's ridiculous because attention is a dynamical process. So it's not going to be a thing that you're going to find in the brain. But it's good to name something attention for communication purpose, such as we know what we're talking about. But of course there's. It's a label. So there's always a gap, especially in psychology, there's always going to be a gap between the labels that we use to speak to communicate about science and actually the real stuff going on, which is constantly changing. Attention is like a dynamical thing. [00:56:48] Speaker B: Why are humans, myself, very much included, so prone to make that leap and say, oh, attention, it's a thing and it's. Therefore it's in the brain and I'm going to find attention in the brain. Why does that feel like such a natural way to think? And it's embarrassing how easy it is to do that. [00:57:10] Speaker A: Yeah, but I think the case of time is really a nice. It's a very. It's very easy to. To speak about this kind of, like, tendency we have because. So we have this feeling of change of, you know, this experience of time. And we speak a lot about it all the time and we say, you know, time went by quickly, slowly, a movie is too long, a trip is too short, whatever. So we constantly, we constantly have those fixed label that we need to use on top of our experience that is constantly changing. And so at the end we end up Confusing the two. We end up basically having the feeling that we can slice divide what's going on in our brain. Because if we take a clutch, we see the clock moving and we have the feeling that it divides our life. And so we, so we tend to, yeah, we get confused, I think at the end, because of language, we get confused, but then we feel things from the inside. And so we said, okay, there is something going on inside. And so why am I sometimes feeling timing passing fast and sometimes passing slow? So then it's obvious that we want to attribute that to our brain. So we basically we localize something that is dynamic first through the language. And then because we feel something inside of us is changing, then we think, okay, well we need to explain it with like neuron. I think that it's pretty, it's quite straightforward. And that's actually, it's typically what you see in people about time. A paper about time perception in neuroscience starts by a sentence saying, time passes fast when we are fun and slowly when we're bored. [00:59:12] Speaker B: But then it says the neural mechanisms underlying this sensation are poorly understood. [00:59:17] Speaker A: Exactly. Because the only explanation, because it is this kind of like subjective things you feel like, then it has to become from your brain. But the problem is that you attributed fast and slow, which are something that are about actually movement, to something that was very actually not movement. It was a temporal thing. It was like your experience, your memory, etc. So you see, I think it makes sense that you think that it becomes its something that is related to your brain activity. And in a sense it is. [00:59:57] Speaker B: It is. It has to be. [00:59:59] Speaker A: Yeah, it has to be. [01:00:01] Speaker B: So make that connection for us then. So you have, you have rats, you have this task where they're on a treadmill and they have to do these timing experiments and they develop these stereotyped motor sequences to basically to help them keep track of when to go back to the port when seven seconds in one case has elapsed. So they can get back to the port right. Just after seven seconds to maximize their reward. So they go through these stereotyped behaviors between trials to do that. And areas like the basal ganglia are doing things that are coordinating there. And maybe, maybe this is where of course it's also in the brain because you're actuating these movements through this continuous perception action cycle. But it's the movements themselves that get honed over time and that you use to, to as your clock. You're kind of using your own movements as a clock. [01:00:55] Speaker A: Exactly. So, but the, the kind of like tricky Stuff here that is very difficult, kind of like subtle, is that we're always tempted that to say animal use their, their, their body and their movement to measure time, but they're not really aware that they have to measure time. [01:01:13] Speaker B: And yeah, so they're just. [01:01:15] Speaker A: So, I think. So I think the key here is to think that we human have this ability to feel time. Okay. The fact that if I stop talking now, something uncomfortable is going to grow and we're going to say, okay, what's going on? Okay, so we're able to do that and at the same time we're able to watch a clock move and kind of like relate our experience of change or internal experience of change with this regular movement. Okay. And that's allow us to kind of like measure. And I like, you know, but the question is that do the animals are able to do that? Are they able to do this comparison? No, I don't think so. I think rats, they are really just in time. They're not comparing. They're in time. They're not comparing with like something and saying, no, no, they're just in time and so they cannot measure. They're just like, look, you know, they're just like, okay, I gotta get my reward. And so they're just, they cannot like step back from time and compare what they've done with something regular. So they're just leaving time. That's why they can do those tasks and that's why you can do whatever you want. So that's my bet. [01:02:34] Speaker B: So humans, again are special in this particular way that they can reflect on their experienced living time with some machines ticking. [01:02:45] Speaker A: Exactly. Well, first was the sun, you know, the rotation of the earth. That's how it started. And then they developed tools to do that very accurately. But yeah, it's exactly that. I think there is something special in the ability of human cognition to be able to, to co register their own internal change with external change. And I don't think maybe. So the key. So I don't think rats are able to do it. Who knows, maybe there could be some condition in which they could do it. Primates might be able to do it in certain conditions, but I don't think they can do. And the key thing is that we do that because we kind of relax. So I don't know. But imagine a rat actually thirsty and wanting to get reward is going to be in time a lot, you know, to your point. [01:03:39] Speaker B: I mean, we are embodied. And you know, reading your paper, I sat quietly, tried to sit very still and just, you know, Time something in my head just match the seconds, right? But of course, I found myself barely nodding my head or like internally vocalizing the seconds, you know, and so there. It's always related to some sort of movement. Even if that movement. Here's what I want to ask you. Even if that movement is just on internal models or representations. Like, even if it's. Do you think of cognition as internalized movement? This is terrible because we're using language and we were just talking about. [01:04:18] Speaker A: Yeah, it's great that you're saying that because I'm trying to write a kind of, like, new shorter paper on that subject. And it's really about exactly that. It's like that. That cognition is a form of, like. I mean, it's really close to, you know, movement and a form of internalized movement. But can it be entirely internalized? That's the big. That's the tricky question. As you've said, as you've said, when you try, when you have to. Time in your head, it's very, you know, you like making those small moves, you know, Recently I took. I participated to online experiments on time perception. And the instruction were, so you're going to see a square, and you have to say, how long did the square appear? But you should not count. You should not nod. What was it? You shouldn't use round numbers. There's all kind of like weird instructions. And I was like, you know, I was thinking about now, but what they should say that you should stop breathing, you should stop blinking. You should. So it's an impossible experiment. And when you have an impossible experiment, maybe this should give you a hint that something is wrong. And I think that's the same with the rats. If you see that you have to, you know, like, struggle so much. To have a rat learn something is maybe the question is not. Is not the right question. And I'm saying that being a guy that has actually, you know, train and design experiments to do that. And now I'm not doing this anymore, and I'm quite happy I'm doing other. And I feel. And time is still a very important thing, but you don't need to put it into this setup of measurement. I think that's not a good. And actually, John was one. Even I think he disagree with many things I say. No, he said one is yes. Because he doesn't like when you go too much into cognition and movement. You know, he has this. [01:06:18] Speaker B: Oh, I know. Yeah. [01:06:20] Speaker A: But he said to me, david, find me an example of an animal in nature that would do a time Estimation kind of task. And it was true that I realized that when we wrote the paper, the 2020 paper, and I wanted to find an example for the introduction, for the first line of introduction. I was really struggling to find the right. What is the right example? It's actually extremely rare, even for human. Extremely rare to have like a pure time estimation experiment. [01:06:59] Speaker B: But that fits exactly with your modern conception. [01:07:03] Speaker A: Exactly. And that fits a lot with what Berson was saying. So that was kind of like the, you know, I needed this kind of like, kind of guy, actually assuming, you know, all the way in that the experience of time is not something different than measuring time. And that what we're doing in neuroscience is that we take the experience of time of an animal and we would like him to measure and say long, short. And that's. [01:07:32] Speaker B: We're like, I'm measuring it. You measure it too. [01:07:35] Speaker A: Exactly. [01:07:36] Speaker B: Yeah, exactly. [01:07:37] Speaker A: So that's great. I think it's great also if you have actually if there's ideas that you push. And what I found really nice is that. Yeah. Is how the animals were telling us, you guys, this is wrong. And actually, when I talk to people, I go visit labs, you know, a lot of people that are doing this kind of experiment, they tell me, oh, we've seen it too. And so what's very interesting is why nobody speak about it, you know, and then also that you have to do an experiment in which, okay, now that we see that the animals are moving during time experiment, you have to think about a way in which the animal is not moving, because otherwise you won't be able to do nature Neuroscience paper that would be purely about cognitive things. Because movement is not the right stuff. Is it kind of nuts? [01:08:28] Speaker B: It is. It's. Yeah. I appreciate that more and more. How arbitrary it is to try to untether our behavior from our minds, because they are. It's just a continuous cycle, analog, continuous. And it's never divorced. Although, you know, even like Jon Krakar would argue, like. Well, actually we do have these internal representations that are divorced. And that's, you know, pretty special. But even it's. It's maybe I don't know where the line is. He doesn't either. No one does. Right. Or whether. Because even if you have this internal representation, it is still continuously connected with another layer, with another layer, with another layer. And there's out into the environment, embodied and in the environment. So I know I'm preaching to the choir here. We're not going to get into a free will debate. But as you were Talking about looking at a clock and measuring it reminded me of the Libet experiments, right? Where you. You're looking at a clock and then you note where the clock is when you volitionally. Whenever you want to like, tap your finger and then you note it. And the famous experiment, and there's been a lot to debunk these things, is that your brain reads out your. What you're going to do before you know you're going to do it, before you report that you have subjective awareness that you're going to do it. Therefore, we have no free will. But. And so there's been a lot of reasons why that, that experimental setup is perhaps not the best, has holes in it, but has. Is there a road into free will with this. With your conception now of. [01:10:01] Speaker A: Oh yeah, no, but well, remember, Remember the translation. The title of the first book of Berkson in French is called Essay Donnet immediate de la conscience, an essay about the immediate data on consciousness. But it was translated in English as Time and free will. That's the title of the book. And actually if you read the book, I really. So the translation is not great, but it's okay. [01:10:27] Speaker B: So you should learn French and read it in French. [01:10:30] Speaker A: You know, what's crazy is that now that I'm talking to philosophers and I'm talking. I've been talking recently to Japanese philosopher people that study Bergson, they speak French and that's, that's. I found that so amazing that, you know, like, like philosopher that studies German philosopher, they actually learn German and we. That's a very different world than our world. But so. [01:10:55] Speaker B: Yeah. [01:10:56] Speaker A: So the book is actually, if you look at the book, the book, the. [01:10:59] Speaker B: The. [01:11:00] Speaker A: The foreword of Berson is that actually the problem is. Want to attack with this question of time. Is the problem of free will of you would call freedom. The point. His point is that, is that the problem of the free will is just like a very badly framed problem due to a sort of mechanistic kind of like approach. He basically says, and that's. Once you've understood dure the problem, the problem of free will totally vanishes. [01:11:29] Speaker B: Oh, how's that? [01:11:30] Speaker A: If every moment is new, okay, so at every moment of our life is a new moment. [01:11:38] Speaker B: So then we're not bound. [01:11:41] Speaker A: We're not bound to anything. It's like we actually creating ourselves. How could you know at each moment. So that's it. There is no. [01:11:54] Speaker B: This could really make us go another few hours. [01:11:57] Speaker A: Yeah, no, so it's very interesting on how he says. Yeah, no, the problem of the way we think about free will is because we think retrospectively, okay. We see something that happened, and then after it's been done, we think, oh, yeah, I can understand why David decided to jump out of the rock at 10 meters high, you know, but actually, when I went, you know, to do that jump 10 meters high in the sea, I'm, like, hesitating. But nobody knows what I'm going to do because I'm done. This is a new moment for my life. Even me. I have no mental kind of, like, internal model of this because I'm a new person doing something new. So actually, this new thing, it's going to define me. If I jump it, I'll be like, oh, yeah, I did it. And I'll be a new person. If I don't do it, I'll go down the road, my son will be looking at me and say, hey, dad, you didn't jump. And so. You see what I mean? But so retrospectively, of course, we can justify. We can explain things, but the question is that when you do something entirely new, how can you explain something that never happened? [01:13:14] Speaker B: But then. Okay, so it's a liberating idea then, that we're constantly. Everything is new in every moment, every passing moment. [01:13:22] Speaker A: Exactly. It's very liberated. [01:13:24] Speaker B: Then why do I have the same stupid habits that I've had for a long time? Why is it so hard to change things? Why am I so predictable in so many respects if I'm creating myself anew in every instance? [01:13:36] Speaker A: Yeah. Because we have this fight between. It's a set of balance between surviving in which we need to somehow take advantage of regularities that are beneficial to us. [01:13:51] Speaker B: Not jump on the back. [01:13:53] Speaker A: Yeah. For instance, if this is to. You know, it can be advantageous in some cases. [01:13:57] Speaker B: Right, right. [01:13:58] Speaker A: This is to impress somebody, like, you want to impress your son. So. So, yeah, so we're gonna get, you know, we'll be able to. Yeah. Take advantage of some kind of, like, regularities to be able to. To live, find food, striving in the world. So. So there is this kind of like. Yeah. Kind of, like competition between some kind of, like, habit in which we. Yeah. We take advantage of the world for things, but also we change. At some point, the bad habit will break or not, but it will change anyway, or you'll get more and more frustrated with your bad habit. I'm also. I think I. Like. There's a word that Berksen uses that if I have free will, okay. I can understand why I need some kind of, like, determinism. To take advantage of the regularities of the things that happens all the time that I can use, okay, that cause and effect. If I have this free will, it's really important that I'm also able to take it. But if I was entirely determinist, why do I have this feeling of free will? I like this one. It's kind of very, kind of a. [01:15:14] Speaker B: It's counterintuitive and it actually, it uses the argument against free will for an argument for free will. If things are deterministic enough, I can actually make use of that. Yeah, I have to make us switch gears here because this podcast, although less and less so, is ostensibly about the natural and artificial intelligence and sciences. What does this mean for artificial intelligence? So, you know, a robot could just actually keep an internal Casio watch clock, right? Why would it, why would this conception or implementation or way to approach time make any difference for an artificial intelligence? [01:15:58] Speaker A: Well, I think it, it makes. So, you know, I'm not an expert in the intelligent artificial, but like, I. [01:16:07] Speaker B: Wouldn'T want my computer to subjectively become bored or to go faster sometimes and slower sometimes. [01:16:15] Speaker A: I want it to be constant. But that's the big difference, I think, and that's why I think people are interested in version now is because this Duray is really something that is not in our computer or that is not in AI. Is that like, you know, I don't know exactly how it works, the AI algorithm, but I. We can imagine that it's, you know, in, in the computer there's clocks that kind of like, you know, that it. [01:16:43] Speaker B: Has to be precise. [01:16:45] Speaker A: It has to be precise and it parses time regularly and, and one beam, you know, is separated from the other one. And that's, you know, then you basically, you stop the computer, you turn it on again an hour later and you know, you can go back to where you were before. But that's exactly not how we. Dure is actually the opposite of that. Dure is the fact that you cannot beam is this kind of like continuous merging that makes that if you stop doing something, you become impatient or uneasy, etc. But I don't think AI yet if you're interacting with ChatGPT and asking him question about French philosopher and all of a sudden you stop asking, he's not going to tell you, hey, what's going on? I'm like. Or even like shut down or, you know, so it's not, it's not built, it's not built like that for the. Somehow from this kind of like accumulation and merging from the past to the present, things are very discretized, I think, in this kind of like. So I think this is what is kind of interesting is that it's very. Yeah, it's a very different. Yeah, there's no time. Basically. Time doesn't matter anymore in AI. No, there's no time. It's just sequence of things. [01:18:07] Speaker B: Dynamics, matter, but time. So would you want an AI to have this same sort of Berksonian dure. Like, would there be an advantage? I mean, there's obviously an advantage. No, no, there's not obviously an advantage for us. Actually, I was about to say I. [01:18:24] Speaker A: Don'T think if it's. Is it possible? Can we. I don't think we. We can do that. I think that's really. [01:18:31] Speaker B: It's dependent on being a living system. You think? [01:18:34] Speaker A: I would kind of like think so, but I'm not. I haven't really thought how you could somehow. Because the idea is that you. We're constantly kind of like transforming ourselves. You would say, okay, an AI system is also constantly growing, updating its weights. Updating. But yeah, I don't feel like that would give. You wouldn't say that it's getting old. No. Or like, you know, like my computer's. [01:19:05] Speaker B: Getting old right now? In a different way. [01:19:08] Speaker A: Yes. But you see what I mean for an AI that is like, okay, now it's. Or you wouldn't. Yeah, you. How would you. So how could you include impatience, like a true impatience? Because the true impatience doesn't have to be played repetitively, you know, because I'm a patient, you know, now I go out, I take my car, the red light is too long. I mean, you know, but it's gonna be different if I do it tomorrow. So it doesn't have to be an impatient. That is replayed all the time. It's got to be new every time. And that's not possible. We want the AI system. It's got to be very regular. When I ask him, what's the birth date of birth? He's going to give me the birth date each time. But if you keep asking me, maybe I'll do you. Maybe I'll be bothered by your question. And I'll tell you something stupid. I don't know if this can come into an AI. I don't think they're designed for that. [01:19:59] Speaker B: So one of the advantages for us having this sense is, let's say the. The hawk is coming down on the mouse and the mouse needs to hurry the hell up and get in the hole. And so Time is going to go very slowly because it needs to move very fast. Right. And that it's, it's Duray in that moment is changed for it subjectively. So. So our timing, our sense of timing is dependent on that, on motions and the needs of our demands from the environment and to survive, etc. But maybe take the example of self driving car. Right. You would want it to. I don't know if the boulder is. Well, let's say David has jumped off a rock 10 meters high thinking that the highway was actually the sea. And you detect David falling through the air and you don't want to contribute to his demise by hitting him with the car also. Right. You'd want your car to be able to slow down and. But I don't think you would actually need Duray to do that. You could still just use clock time if you're the. [01:21:04] Speaker A: Yeah, yeah, yeah. [01:21:05] Speaker B: Are we just constrained because we are not. Because we don't have an internal clock, we can't use clock time. We have to use this. Duray. Is that one way to phrase it? [01:21:15] Speaker A: Yeah. Duray is making itself in us. Whatever we do, it's imposed to us. We're changing right now. Like, you know, like, you know, there's like, you know, we're growing some reflection about our discussion and then so it's like we cannot escape it. It's kind of a force of change in a sense. We're not going to stay immobile or, you know, something is going to happen with time for sure for us, which I don't think is the case for an AI. Like if we stop it now, it's not going to say, hey guys, take care of me or whatever. No, because I mean, we're like, you know, we have those metabolic needs that we need to, you know, so we are in perpetual kind of like disequilibrium. And so time is actually is important for us. [01:22:08] Speaker B: And is it in that sense that Bergson also conceives of time essentially as a force upon us? [01:22:15] Speaker A: Exactly. It's like it's going to do something on you. It's an active. It's an active thing. And that's actually why, actually. And that's what you see a lot. And that's what's great is actually when you do those time experiments where you ask animal estimates, you're constantly surprised at. Why do the animals always go too early? Because time is acting on us. And so actually for the small, the small kind of like story. With this time experiment we designed with Pavel at the beginning, we Wanted the rats to wait 10 seconds. [01:22:49] Speaker B: Okay. [01:22:50] Speaker A: Because we thought like this, we would get, like, a lot of good units, you know, like a good stable chunk of units for 10, 10 seconds. And then we were really pissed because the rats, they were. When they started doing this task, they were like, 9.5. [01:23:03] Speaker B: You're too. [01:23:04] Speaker A: Yeah. So we said. We said, okay, let's move down to 9. And then they moved on immediately, 8.5. And so we kept moving down, and then at some point we realized that they were like, you know, they would just want. So I think, and this is true in, like, if you look at a lot of different papers, like the work of Ben Serlevsky, if you look at the data, the animals, they really struggle to wait. And in that sense, that's where you can see that they acted by time. They want their reward as soon as possible. Time is important for us, for them and for us, too. [01:23:39] Speaker B: So then just to wrap up our little AI segment here. So not only can you not imagine why anyone, why AI engineers would want to figure out how to implement or program in this sense, but you can't imagine that it's possible in a machine. It has to be a living being. [01:24:02] Speaker A: It has to be a living being for which time matters. [01:24:06] Speaker B: For which time matters. Are there living beings for which time doesn't matter? [01:24:09] Speaker A: No, all living beings. Well, I guess maybe for plants, it's a little bit different. [01:24:15] Speaker B: No, you could think time, because they're constant, they're having to create themselves. [01:24:19] Speaker A: Well, but, you know, they're just like in the place in which actually, you know, they get their food for free. They don't, you know, so they have. [01:24:27] Speaker B: To, like, their roots have to go down. They have to bend toward the sun. They have to do. They still have to, like, configure. But that's a plant cognition conversation. [01:24:35] Speaker A: Yeah, but you see. You see what I mean? I think, I guess what you would have to design is something like, if you were putting an AI under pressure, then maybe. Maybe I shouldn't say that. We don't want to go there. [01:24:46] Speaker B: Please. And also, I don't want an AI to be impatient with me. Come on, hurry up. Ask a better question. Come on. [01:24:55] Speaker A: Yeah, exactly. So that would be the only. The reason why it's like, is time matters for AI. No, it doesn't. No. But for us, time matters. [01:25:07] Speaker B: You know, another thing you mentioned in your paper is a. Again, I see it as a sort of recent trend among people like you and more increasingly me, of saying, oh, doing this. Okay, from my perspective, there's this kind of recent rah rah, science needs humanities sort of movement. And I always kind of question that, thinking, well, does it really? Or does a certain segment of scientists need humanities? And those can be the people who can, who connect it. But so that was kind of thrown in there also. And I'm curious what your take is. Like, why are we hearing this more and more that the science need humanities? And how you got from this idea that time is not in the brain to science needs humanity is important. [01:26:03] Speaker A: So the idea if we stay on the time topics is that impatience. So this way we are changing in time all the time. Because it's changing all the time. It's basically unreachable by science. We're always going to be a little bit behind, you know, we're going to lag behind all the time in this description. So we'll do a description of the living that is actually a mechanical description. [01:26:34] Speaker B: Because it's the best approximation we can do in the given moment. [01:26:38] Speaker A: Exactly. Yeah, exactly. So there will always be a sort of like gap between the mechanical kind of like stuff and the real changing creative process that is life. And so, and so then if there is a gap, then there might be other way, you know, to address it. So for instance, you can learn a lot about perception with visual artists, okay. Because they're gonna, you know, do you some, some experiments and you won't be able to actually. They won't, you know, it's, there's no point of putting electrodes while you're watching stuff or etc. No, it's just gonna be, you're gonna, you know, it's a different kind of experience because it's just focusing on the experience itself. Okay. And because it's a new experience, to do science, you need to repeat an experience. Let's say like this. Very simple. If you want to do a science, something you need to repeat. How would you repeat somebody watching a piece of art? It won't be the same once you've seen it, the second time will be by definition different. It will not be the same. So you won't be able to do science. Actually, it's a, actually I think it's an under, kind of like appreciated phenomenon in neuroscience. We want to, we try to have the animal doing the same trial over and over and over. And they don't actually, it's not true. It's not, you know, we would like them to behave like robots, but they don't. So my point with the art stuff is that there will be a limit in which, you know, because of this novelty stuff. And so then we can just talk about it in literature. Literature will give you a sense of what's happening in the mind of an artist creating or a character watching a piece of art. That will be much more as valuable in form of knowledge of humanity than knowing what's going on in his brain. [01:28:35] Speaker B: But that's okay. So then that's separate from what I think of as science, which is where you want to be able to reliably reap, produce results. So that's its own thing. That's not science using humanities, it's like a different. It's almost not science. Right. It's just a different description, a different story of experience. [01:28:57] Speaker A: Exactly. And it's a valuable one. [01:28:59] Speaker B: Okay. [01:29:00] Speaker A: It's not sure that it's failing more than science in the sense that, I mean, science is great and it's doing, approximating a lot of things. There's no question about the benefit of scientists. But it's because it's like kind of always lagging behind. Then let's not discard other form of approach to reality. Arts is one of them, literature is one of them. [01:29:29] Speaker B: But this is different than bringing, I'll just say humanities to encompass all of them. Bringing humanities into the science, it sounds more like appreciating the humanities as a different perspective. [01:29:41] Speaker A: You're right. Okay, so that was kind of my original point. Now the only maybe little twitch that I could say is that, well, for instance, so we often. There is often like the tendency to think that neuroscience is going to help philosophy. I feel like my re. Encounter with Berkson was the opposite. It's like basically Berkson for me, but it's not, it's still a debate, but for me, he's kind of like solving a problem in science. [01:30:08] Speaker B: Well, it changed your perspective. It changed the way that you approach the problem. Right? [01:30:12] Speaker A: Yeah. Well, you can see, you know, there's an entire committee that is struggling with trying to have rats doing time estimation experiment. And there's a guy that say, hey, maybe it's because you're confusing time and space. That's cool. You know, and I think that's great. I think, you know, it's, it's, it's interesting. It's not to think that every experiment is a good one. Maybe there's experiments that are just, I mean, another. I think your guest Paul Cisek was there. [01:30:42] Speaker B: Paul Cisek? Yeah. [01:30:43] Speaker A: Yeah. He has a very nice paper. I think at some point it's the introduction of one of his papers saying that, you know, the toughest part in science is actually to find the right question. And I think it's really true. And it's. Sometimes we ask questions that are like some kind of like, you know, very quick, superficial psychology, and then we apply it to animals and then it fails. I think that's the case. So in my. In my case with Berson, I felt like, yeah, I think, well, I think people should take, you know. Yeah. Should read him and actually take in account is. And maybe it's redirect science. So this was something else with. What I liked a lot with Berkson is that is actually all his philosophical work is very tight to science. [01:31:35] Speaker B: See, that's what. Yeah, I was about to say is I have my own internal dialogue sometimes, like, oh, is what I'm interested really philosophy or am I interested in science? And really what I'm interested in is just knowing stuff and I'm curious about stuff. But I think it's easy to. Once you start sort of opening that door to philosophy, then it's easy to kind of get hung up because you get immediately into the debates and the semantics around the concepts. And then what? And then you can just get lost there. So having it always having like your perspective where you had already this sort of scientific data set and viewpoint and questions, and then you visited revisited, in your case, Bertrand, who you revisited in light of your specific set of questions and problems. And that was effective. And that's where philosophy can be effective, I think, because, you know, says, oh, philosophy needs to be like the humanities. Philosophy needs. People need to read philosophy. But you can't just go read philosophy. You have to go with your set of problems. [01:32:37] Speaker A: I think you have to interact. I think the key here is to interact with people. When you do, the risk is sometimes I feel like, yeah, it's a little bit too much closed society, you know, philosophy. Well, maybe both philosophy and neuroscience, they tend maybe to be a little bit too, you know, in their thing. And I think the mix is great. And what is very interesting is that Bergson was actually saying philosophy should be much more like science. And despite the fact that a lot of scientists were really pissed at him and like, were like calling him like really, like kind of like a rubbish. But he really. He had this idea that. That what was lacking philosophy was the precision of science, of science. [01:33:22] Speaker B: And I think it's funny because he got flack for. Because he's very fond of using metaphors. Right. [01:33:28] Speaker A: And that's exactly because he's not a scientist. [01:33:31] Speaker B: Right. [01:33:31] Speaker A: But he was Trying to find actually good metaphor. And I think his metaphors are really. Sometimes it's really not. I mean, he's. I love reading. He's really very. It's very precise, very sharp. [01:33:41] Speaker B: Well, that's how we think is metaphors. Right. George Lacrosse. Yeah. [01:33:45] Speaker A: Yes. [01:33:46] Speaker B: Yeah. Oh, yeah. I had this thought before we spoke. I was walking my dog and I was thinking about philosophy and science. And I remembered a recent conversation we were having in my lab, actually, and the topic of whether pineapple is good on pizza came up. And of course, we all had our opinions on this, you know, and we were sort of debating it. And then one of my colleagues, Mark, said, I don't understand why people are so adamant about their opinions about this stuff. And I thought that's kind of like the way I feel about scientists and their opinions of philosophy. Like, why do you have to have an opinion on whether someone is interested in and uses philosophical inquiry to aid their own science? Right. Like you think it's useless. Other people find it useful. Who cares if there's pineapple on the pizza? The person eating the pizza likes the pineapple. There you go. There's a metaphor. There's an analogy. [01:34:46] Speaker A: That's a nice. That's a nice one. But you think. Do you really think that people think that philosophy is useless in neuro sense? [01:34:56] Speaker B: Of course. Like there's tons of historical examples of scientists talking about how useless philosophy is. Yeah. [01:35:02] Speaker A: But that big names, you know. But I feel my impression. I was extremely surprised by. By each time I gave a talk about this stuff. Like how people were really engaging. I feel like people are actually hungry for doing meaningful stuff. And if you do an experiment and you wonder, why does it take you so long to train your rats? Well, it's kind of cool also to have this perspective of philosophy of people also that think about science. I think it's. Yeah. And I feel people are hungry about that and students a lot. And I think that's really great. That's positive. [01:35:49] Speaker B: David, hopefully I have not taken you over your personal durer, but I've taken you over clock time. So I've a little bit. [01:35:57] Speaker A: But it's okay. [01:35:58] Speaker B: Yeah. Okay. My final question is pineapple on pizza, yay or nay? [01:36:04] Speaker A: No. [01:36:05] Speaker B: Okay. Spoken like a proof. Sorry French person. But you're okay with other people having pineapple on pizza? [01:36:11] Speaker A: Yeah, totally. Totally, totally. [01:36:13] Speaker B: Okay. All right. Thank you for your Duray. [01:36:16] Speaker A: Well, thanks, Paul. It was really fun. [01:36:24] Speaker B: Brain Inspired is powered by the Transmitter, an online publication that aims to deliver useful information, insights and tools to build bridges across neuroscience and advance research. Visit thetransmitter.org to explore the latest neuroscience news and perspectives written by journalists and scientists. If you value Brain Inspired, support it through Patreon to access full length episodes, join our Discord community and even influence who I invite to the podcast. Go to BrainInspired Co to learn more. The music you're hearing is Little Wing performed by Kyle Donovan. Thank you for your support. See you next time. [01:36:56] Speaker A: It.