BJKS Podcast

71. Lynn Nadel: Memory, The Hippocampus as a Cognitive Map, and the importance of behaviour

April 23, 2023
BJKS Podcast
71. Lynn Nadel: Memory, The Hippocampus as a Cognitive Map, and the importance of behaviour
Show Notes Transcript Chapter Markers

Lynn Nadel is an emeritus professor at the University of Arizona, where his research focuses on the role of the hippocampus in memory. In this conversation, we talk about the early years of Lynn's career: why he chose to do chemistry, how a course with Donald Hebb made him switch to psychology, how his postdoc was disrupted by the Soviet invasion during the Prague Spring, John O'Keefe's discovery of place cells, how Lynn and O'Keefe wrote The Hippocampus as a Cognitive Map, and much more.

BJKS Podcast is a podcast about neuroscience, psychology, and anything vaguely related, hosted by Benjamin James Kuper-Smith.

Support the show: https://geni.us/bjks-patreon

Timestamps
00:00: How Lynn went from studying chemistry to doing a PhD on memory
08:35: What was it like working Donald Hebb?
15:16: The golden era of cognitive neuroscience at McGill in the 50s and 60s
23:14: Lynn's postdoc in Prague was interrupted by the Soviet invasion during Prague Spring
36:29: The discovery of place cells and the writing of The Hippocampus as a Cognitive Map
50:59: A paper or book Lynn thinks more people should read
54:55: Something Lynn wishes he'd learnt sooner
57:38: Advice for early career scientists

Podcast links

Lynn's links

Ben's links


References and links

Episode w/ Kate Jeffery: https://geni.us/bjks-jeffery
Konorski: https://en.wikipedia.org/wiki/Jerzy_Konorski
JZ Young: https://en.wikipedia.org/wiki/John_Zachary_Young

Goddard (1983). The kindling model of epilepsy. Trends in Neurosciences.
Káli & Dayan (2002). Replay, repair and consolidation. Adv in Neur Info Proc Sys.
Klein, Cosmides, Tooby & Chance (2002). Decisions and the evolution of memory: multiple systems, multiple functions. Psych Rev.
Konorski (1967). Integrative activity of the brain; an interdisciplinary approach.
McClelland, McNaughton & O'Reilly (1995). Why there are complementary learning systems in the hippocampus and neocortex: insights from the successes and failures of connectionist models of learning and memory. Psych Rev.
Melzack & Wall (1965). Pain Mechanisms: A New Theory: A gate control system modulates sensory input from the skin before it evokes pain perception and response. Science.
Nadel & Buresova (1968). Monocular input and interhemispheric transfer in the reversible split-brain. Nature.
Olds & Milner (1954). Positive reinforcement produced by electrical stimulation of septal area and other regions of rat brain. J comp & phys psychol.
O'Keefe & Dostrovsky (1971). The hippocampus as a spatial map: preliminary evidence from unit activity in the freely-moving rat. Brain research.
O'Keefe & Nadel (1978) The Hippocampus as a Cognitive Map. Oxford University Press.
Rao & Ballard (1999). Predictive coding in the visual cortex: a functional interpretation of some extra-classical receptive-field effects. Nat Neuro.
Ravindran (2022). Profile of Lynn Nadel. PNAS.

[This is an automated transcript with many errors]

Benjamin James Kuper-Smith: [00:00:00] Yeah, I mean as I, as I kind of said before we started recording, I'd like to kind of go through, uh, your career and then kind of use that to learn about memory in hippocampus and all these kind of things. And I thought we could maybe start with something I read in a profile on you, I think in PNAS, which was that your father was an industrial chemist, and then you studied chemistry at university and then very quickly, no longer studied chemistry at university. 

I was just curious, what was the, I mean, was it as obvious the motivation for you to start studying chemistry as it sounds that your dad did it and then you thought, okay, I'll do it. Or what was the motivation to study chemistry and then to no longer study chemistry?  

Lynn Nadel: I think it was more that it was what my father had done. 

I didn't really have a particular thing I wanted to do, so the university, I chose to go to McGill in where I went and the places I applied to were all good in chemistry. You know, those were the places I chose to apply to. And so I went to McGill [00:01:00] because it had a good, uh, chemistry department. In fact, it had, Rutherford had a Nobel Prize winner, had been at McGill's, so it was a, in chemistry. 

So it was a, you know, a good choice for somebody interested in chemistry. But I wasn't like devoted to chemistry. I wasn't a kid playing the chemistry sets or anything like that. I, you know, I, I didn't have a big, a big focus on it. And it became, once I got to McGill and I enrolled in my first chemistry class, and I took my first chemistry lab, serious chemistry lab, I had done some chemistry lab work at, at high school. 

I'd gone to Stuyvesant high school, which is a sort of a special high school, a test-in high school in New York City where a lot of the more academically oriented kids in the city go to either Stuyvesant or Bronx High School of Science. I went to Stuyvesant, did some chemistry, got to McGill, went into the chemistry lab, and within two or three, Sessions in the lab, it was pretty clear that I was not cut out to be a [00:02:00] chemist. 

At least not if I had to lab work, I was probably going to be dangerous to others and myself if I persisted in that. So I, so that was, it was really within the first semester, it was clear that chemistry was probably not my future. So I started looking around for something else that might be interesting and I enrolled in, uh, I enrolled in an introductory to psychology class because why not? 

And um, just so happened that that class was taught, taught by, by D.O. Hebb, who was at McGill and was very famous. I didn't know that right When I enrolled in the class and I took this class with him, and, uh, that was it basically. Now in retrospect, I remembered back when I spoke to my, my mother about it many years later. 

She said, well, you know, when you were young, you, you were, you had expressed an interest in why it, you know, what is, what goes wrong with people when they're, [00:03:00] when they have mental disorders and things like that. You had expressed an interest in figuring out, you know, what goes on, you know, in people's brains when things go wrong. 

It was something you talked about when you were younger, but you know, not something you obsessed about, but you mentioned it. So apparently I had some interest in these things and I, and it got completely kindled by taking the course with Hebb, and that was it. I mean, once I took that course, it was clear this is what I wanted to do, this is what I was really interested in doing, but I wasn't sure whether I should be, you know, approaching it as a doctor or as a researcher. 

Mm-hmm. I wasn't aware. Of course, you could be both at that point in time, you know, you could I be you. So I was really shifted into a pre-med track. Although I was majoring in psychology, I was taking a lot of psychology classes, but I was pre-med more or less. And then I, uh, didn't get into medical school because I was, uh, shall we say, uh, not a perfect student. 

For the first few [00:04:00] years I was at university. Uh, so my grades weren't good enough. I, I was quite good in my third and fourth years, but my grades weren't good enough. I didn't get into medical school, but I was in Montreal and I, by that point, I was married and I may have even had a kid or had a kid on the way. 

And you're not sure. Well, I'm trying to place the years that my first kid was born in 64 and I was not. Yeah, that was the year I was in between. So having not gotten into medical school and, and being quite connected to folks in psychology, because I had taken a lot of classes, I, I got a job in a lab working for one of the professors. 

I got a job as a tech, as an RA in Dalbir Bindra’s. Lab. Bindra was a full professor, interested in motivation. Most of his work had been on humans, but he got interested in animals and he was doing some work with animals  looking at the effects of various drugs on spontaneous behavior [00:05:00] in animals. 

So I spent a year, my year off, so to speak, my gap year, my involuntary gap year, working in the lab, basically injecting rats with various drugs, including LSD which was freely available.  This was before it became popular and it was at that time just beginning to, to sort of be usable as a psychedelic, but researchers could still have access to it. 

So Bindra had bunches of LSD sitting around in drawers, pure Sandoz LSD. Little did I know, probably worth millions of dollars. But anyway,  I was injecting rats and looking at their behavior. And then I applied to get into graduate school, uh, at McGill.  McGill had a policy of never letting its own students, students who did a degree undergrad to do grad work. 

It was like, there had been one exception in 50 years or something like that. But I, [00:06:00] I guess I got on well with Bindra. So he, he, he kind of convinced folks there to let me get into the graduate program because I hadn't really been, you know, a psychologist as an underrad anyway, well, for whatever reason they took me into graduate school. 

And that's how I got started. And I started out as a teaching assistant in Hebb’s introductory class, the one that I had taken, you know, as an undergrad myself. So then I got to interact with Hebb and, and so on. Now at McGill as a graduate student, my interest immediately zeroed in on memory because, you know, Hebb and cell assemblies, and of course the patient HM had been, you know, studied in Montreal a lot. 

I mean, the Montreal Neurological Institute, where was, was where the work on the patient HM was done. Even though the surgery was done in Hartford, Connecticut, they didn't have the neuropsychologist to do the, to look into HM.  So Scoville the, um, everyone knows this, [00:07:00] by the way. I'm, I'd be talking to people who know this. 

Scoville contacted Penfield at the Montreal Neurological Institute, and Penfield contacted Hebb and said, You know, I've got this interesting patient. Somebody said they wanna look at, you know, you got somebody who wants to look at it. And Brenda Milner was Hebb’s student, graduate student at that point. 

Yeah. And that's how Brenda Milner got onto HM. Now here's a crazy coincidence. Brenda Milner, very quickly was working with HM from the fifties, late fifties on into the sixties. I was a graduate student and I was at McGill in the early sixties. And as a second year undergraduate, this would've been 1960, 1961, I roomed with two people, one of whom was named Bud Corkin, who married Suzanne Corkin, who was working with HM. 

So I found out about HM or, or heard about HM, indirectly as an undergraduate without ever thinking it would mean anything to me basically. [00:08:00] I become a graduate student. I'm interested in memory, and that's how I got going on the projects I got going on one looking at, at memory in cortex using, uh, cortical spreading depression, a technique which had been, um, brought into the field, so to speak, by Jan Buses, who worked in Prague at the Czech Academy of Sciences. 

I used that technique in my master's thesis to study the role of cortex in a kind of learning. And then I shifted to hippocampus after that for my PhD.   

Benjamin James Kuper-Smith: Yeah, I, can I ask briefly about Hebb, kind of what it was like? I mean, you, you really mentioned that his, uh, introductory course seemed to have had quite the effect on you and then, but he was, was he head of department? 

Lynn Nadel: At the time? 

He was the head of department, sorry. Yes. He was the head of department by that. You know, I, at that time, I, I didn't understand how crazy it was to try to be the head of a department and also, you know, [00:09:00] run a, you know, run a research lab. I found out about that later. Uh, yeah, he was head of the department. 

All the people that worked with animals were in one building, you know, closer to the medical school complex. The people who were in psychology worked with humans, were in another building. We weren't together at that point. That happened a few years later. They built a new building. We all came together. 

So at that point, Hebb was over here and the animal researchers were over here, basically like 15 minutes away, walking or something. So we didn't see a lot of each other during the years. When I was a, when I was a graduate student, I saw him enough because I was teaching, I was a TA in his class, and because I took some seminars with him, but, you know, one didn't see him a lot because we were in a different building. 

The animal folks were, and, and who did we hang out with there? It was more Peter Milner, who was of course quite famous for his co-discovery with, with Olds, uh, brain self stimulation, that's Olds and Milner. In 1954, the first kind of paper [00:10:00] showing brain self-stimulation reward, that was Peter Milner, who of course at that point was married to Brenda Milner. 

Small world. Right? And so, and also in that group was, uh, was Ron Melzack. Ron Melzack was the Melzack of Melzack and Wall, of the gate control theory of pain. And Melzack had recently come to the department and one of his first graduate students was John O'Keefe. Okay. So all of these pieces came together. 

Now we were all kind of in different places. I interacted with Hebb maybe more than some of the other students because I kind of took him on as a, or he took me on one way or the other as a mentor, my actual advisor.  Bindra, who was a fabulous person, really a wonderful person, died way too young, by the way. 

He didn't know much about animal research because he was a human researcher. So I actually got most of my feedback, mentoring about animal [00:11:00] research, either from my fellow students or from Milner or Melzack who knew a lot more about animal stuff than Bindra did. So it was a funny, you know, a funny time. 

But so, but I did have a fair amount to do with Hebb, given those constraints. He was a fascinating man. He was a kind of a, in many ways, a dour Scot kind of person, you know, that's his background. He, he was born in Nova Scotia and he went back to Nova Scotia when he retired. He was a kind of a feet planted firmly on the ground, no nonsense kind of person, no pretension, uh, gruff, hard on his students. 

Uh, you know, he was a tough task master, but he was a, um, As they say, he was a teddy bear inside. I mean, he, he, uh, when his students got into trouble, he was the first one to help them. And of course this was the sixties. So many of my fellow graduate students, shall we say, got into trouble. It was, uh, you know, it was a [00:12:00] period of much experimentation, shall we say. 

And, uh, but, and he was, was quite helpful when, you know, for, for, but his attitude was basically if, if you, he threw, he threw his students into the water and if they figured out how to swim, so to speak, then they could survive. If they couldn't figure out how to swim, that is how to do research that mattered. 

How to be a good graduate student, blah, blah. If they couldn't figure it out without too much input from him, by the way, then he would throw them a life raft and tell 'em they should probably think about a different career. So, you know, he was firm, but also at, at critical moments, quite supportive. Uh, I liked him a lot. 

I had a lot to do with him. He later on, you know, perhaps we get to, when I was in London, he did a sabbatical, uh, at University College, London, in the psychology department when I was in anatomy. So we interacted at that point in time in 1974, it was 74, 75. And then when he [00:13:00] retired back to Halifax, he would come into the psychology department at Dalhousie University, which is the university in Halifax. 

Quite a good university, by the way, with a very strong psychology department. He would come in once a week to that department. As it just so happens, I spent two years in that department from 77 to 79. We can get to that later if it's worth talking about. So I had another two years of interaction with him at that point. 

And I also sort of tentatively got caught up in. Perhaps joining him in co-editing the, the last edition of his introductory textbook, the one that I had taken as a first year, second year, first or second year undergraduate. But that didn't pan out. I, I didn't, that was, that was my bad. I did not handle that properly. 

I was not prepared to do that. I, I semi committed to it and then really didn't do it. So I was a bit of a disappointment to have in the end, I think. Uh, but we had a, but we had a good relationship and he was a fascinating and incredibly smart guy. I mean, [00:14:00] uh, you know, just his first year graduate seminar was kind of famous. 

Hebb’s seminar was the famous seminar that all the first year graduate students had to take. And he would be sitting at one end of a long oak table in, in the medical school library, blowing smoke rings from the pipe that he was always smoking and asking very tough questions of all the graduate students, a lot of them about philosophy, by the way, come back to the philosophy point later. 

And if you didn't get it right, he was pretty harsh. But if you engaged him and actually got into a debate with him and you were winning the debate, he'd switch the subject and he, and he ran the whole, so he, he was, he was a really, a good object lesson in, in, uh, many ways. And then when I, you know, got into the position where I, you know, was teaching graduate students, I created a Hebb seminar just like his, I mean, I created a first year seminar for all the first year students to take, just like I took, so to speak. 

And, um, tried to emulate, [00:15:00] you know, what, what he did with the first year graduate students, you know, badly, I suspect. But anyway, I tried. Yeah. So Hebb was a formative person in my experience. Absolutely certain, clearly a, an incredibly important person in the field.  

Benjamin James Kuper-Smith: Yeah. I mean, it, it sounds also like when, when I listen to just some of the people you mentioned from the time at the place, it seems like. 

You, you randomly went to McGill to because of chemistry and then you're like, whoa, that didn't work out. And then you happen to like just fall into like one of the most influential like decades or I know decades necessarily. But like the people you just mentioned, it's, this is crazy. Like, I mean, I guess many of them only became famous and after the time though, I assume John Akee was probably just, I dunno, maybe you can tell me more about that later, but I'm assuming he was just one of the graduate students there. 

Um, I dunno, maybe he was already a standout then, but yeah. I'm just curious, like, were you at all aware of like what was going on at the time than who you were interacting [00:16:00] with and how, I mean, I don't like the word influence necessarily, but you know, just like how cool the things were that people were finding out there at the time, or is that just com that just broke straight over your head? 

Oh no, I,  

Lynn Nadel: I think we understood how cool the things were that people were working on. I don't think, I certainly didn't understand how unique the setting was. And you got it exactly right. I mean, and I have me mentioned this at many points, I've been unbelievably lucky. Basically. I mean, this was, this was pure luck to have been in that place and then find myself in that environment, you know, surrounded by that group of people. 

And as you say, I could, I could have been anywhere. I, I didn't go there for that purpose. I mean, that was incredibly lucky. And the environment was fabulous. I mean, John O’Keefe was one of a handful of the graduate students in the cohort. He came, he started a year before me.  I was doing my gap year when I was doing [00:17:00] research in the department. 

So I was already integrated. Everybody assumed I was a graduate student, even though I wasn't even in the program yet. I was being treated as a kind of a graduate student because I knew all of them and we were all interacting together. And so I met John right away when he first showed up, and he was one of a handful of incredibly smart students who were in the department. Um, he certainly is the one who was, you know, who ended up achieving, you know, at obviously a crazy level. Um, but there were others at the time who we thought were better. I mean, if, if, if at that point in time we had said, oh, who are the, who are the few who are gonna make the, the, the biggest mark? 

I mean, John might have been in that category. I might have been in that category, but there were a few others who were, you know, who everybody agreed they were the top right. And some of them did. I mean, neither of the two that we all thought were the best actually had a [00:18:00] significant career in the end for a variety of reasons, uh, which we don't need to go into. 

But, but there were other, Graham Goddard was, was, uh, a, a year or two ahead of us. Now, you may not know that name, Graham Goddard, but he was, he was maybe the most important figure in the study of the amygdala in the 1960s. His dissertation was on the amygdala. He's the one who discovered kindling in the amygdala, kind of the effect of stimulation leading to the emergence of seizures in amygdala called a kindling effect. 

Graham was a, Graham was an incredible, uh, impactful, important person. He went on to create really strong departments at, at, at, um, Waterloo. He first went to Waterloo in Ontario and created a, a strong department. He then went to Dalhousie, which is in Halifax, which is why I ended up there. We, we can get to that later about how that happened. 

And then he went to Dunedin in New Zealand to sort of create the [00:19:00] department in Otago University that then became a very strong department in hippocampal research and, and amygdala research because Graham, so he did, he was a serial creator of strong, uh, brain behavior psychology departments. He got killed in a hiking accident very young in, in New Zealand. 

Benjamin James Kuper-Smith: Sorry, was that who Kate Jeffery talked about? She, exactly,  

Lynn Nadel: exactly right. Okay. Kate Jeffery would've  

Benjamin James Kuper-Smith: referred to. So in, for those Sudan I interviewed Kate Jeffery, uh, one of my first episodes, and she mentioned how her masters and I think potential PhD, I can't remember exactly what the, but her master supervisor died in this hiking accident and she was very close actually also hiking with friends at the time or something like, it's a crazy story that she tells in the beginning. 

Okay. So,  

Lynn Nadel: yeah, that's the person. And Graham was a very close friend, you know, to, you know, for a, for, for many of years to me. He spent some time in London when John and I were writing the book, and in the early seventies, he gave us incredibly good feedback on, on early drafts of the book. 

So Graham was just somebody who played a really, so the, the, the atmosphere in the department at, when I was a graduate student, I didn't understand. How unique it was. To answer your question, I had no idea. Uh, you know, the privilege and you know, that I was being extended by that. Not just the people who were there, but the visitors who came. 

I mean, all the biggest names in the field, of course, wanted to visit with Hebb. So we got to see the, you know, the, the most famous people in the field came through McGill. They gave talks. We met them, we interacted with them. I mean, we as graduate students, we were just living in this rarefied world of the top echelon of what has become cognitive neuroscience. 

We had no idea. No idea. And as somebody who was, who went to undergrad at McGill, I also had no idea that [00:21:00] most people who were being trained in psychology in North America were having their heads full of nonsense about behaviorism and, and, and stuff like that, and how unimportant the brain was to, you know, for psychologists and blah, blah, blah. 

I was in Montreal listening to Hebb say, if you're gonna be a psychologist, you have to study both physiology and psychology. You have to put the brain into behavior. I never imagined that there was a whole field of psych full of psychologists who didn't think it was important to study the brain. So again, the privilege of being, you know, in a place where that was clearly understood right away. 

Right. Whereas most of the people being trained in the sixties, in most places in the US were getting a rather different picture, you know, of, of how to approach, you know, what has become kind of cognitive neuroscience and neuroscience in general, uh, enormously privileged and lucky and had no idea how lucky I was. 

Yeah.  

Benjamin James Kuper-Smith: Yeah. I mean, I, I. [00:22:00] Maybe quite been in such a place, but I did, you know, do one year of my masters at ucl and it was this weird thing where, because I I, I did my undergrad at at Goldsmiths, which is also in London, but it's a much smaller place. And you know, there whenever someone vaguely famous would come along, you'd give, be really excited and watch their talk, whatever, and U at UCL was just, you'd just, you'd just get completely bored by like the biggest names of neuroscience coming and giving a talk because like, oh, well tomorrow there's the same like someone has been doing. 

Yeah, it's, it's, yeah. Well it was funny to me, like how quickly I got used to it. How funny was it? You know, like, oh yeah, now I have a lecture Bob from Shortz and next week is by Peter Diane or whatever. You know, just like, you just kind of get used to this. Yeah. It definitely sounds like that time in what It was a pretty  

Lynn Nadel: special time. 

Um, it was a very special time and sadly the department sort of went into decline after that or apparent decline. I don't want to dis colleagues. Yeah. Yeah. I think they would agree that, you know, the, that era was a golden [00:23:00] era, the fifties and the sixties, that McGill was a golden era and maybe it would be impossible to recreate, you know, what, what was the case during those years. 

I was about  

Benjamin James Kuper-Smith: to say, I think every, you know, everything that's a golden era at some point. No longer be a golden era. Uh, I wanted to ask then, I mean, so you already mentioned your, uh, you then you did a postoc in, in Prague, or you started a Postoc in Prague. I guess we'll get to exactly what happened there then. 

Um, but yeah, so you mentioned that you already used the, the technique of the, the person who was in Prague, which I guess also answered my question, which is why did you go to Prague? Because I guess have to be slightly careful because I have listeners from the Czech Republic, but I, I checked. Um, but you know, it's, it's pretty unusual I guess for people from the us, Canada, Western Europe or something to go to Eastern Europe in general. 

Right. To, to do research. Yeah. Maybe can you, uh, elaborate a bit more on like. Also, I guess like for you, what the decision was or how you made the decision to go there, and then [00:24:00] maybe what then happened when you went prag and why you had to leave?  

Lynn Nadel: Well, one, one of the two people at the graduate program that I said we all thought was gonna be the s the real success who didn't, uh, was a, was a friend called Phillip Liss. 

Not a name you would have heard of. He was brilliant. Uh, he ended up schizophrenic and, you know the ending is sad at this point. He was a graduate student. He was a sort of quirky, brilliant graduate student, and he took advantage of the fact that a very famous Polish scientist, a neuropsychologist named Konorski, you've heard the name Konorski. 

If you haven't, you should go look him up. He came out of the Pavlov tradition. He was a very famous, physiologically oriented psychologist, wrote a very important book that came out in 1967. Anyway, Konorski came through our [00:25:00] lab to visit in 1965. Short guy. I'm short, but he was short guy, dynamo, incredible energy, amazing guy. 

Fascinating. Came and talked with all the students and did like a chalk talk, you know, and we all, we had incredible. Anyway, Philip Phil decided, I want to go work with this guy. So Phil got a, got a postdoc fellowship from N I H to go work in Warsaw at the, at the Nencki Institute for Bio, for Biological, whatever. 

Nencki is still a very famous institute. Konorski was at the Nencki. Phil went there and he wrote me and said, This is fabulous. You know, this is a great thing. It's really interesting, blah, blah blah. So that sort of opened the door to the idea of going to Eastern Europe. At that point in time, N I H was still giving out a very small number, but giving out postdoctoral fellowships to people to go outside the USA. 

There were handful. [00:26:00] So both John and I applied for such fellowships. John applied for one to go to London to work with Pat Wall, the other half of the Melzack wall pain thing, cuz John was interested in dorsal columns at that time and pain stuff. And I applied to go work with Bures and we both got these NIH postdocs and, and so I was open to going to Eastern Europe because of Phil. 

But also at that point in time, this is the 1960s, 66, 67, lot of political stuff going on. Uh, I was also interested in, actually interested in going and living in what was a socialist country. I mean, I was naive enough to think, you know, that there was some reason to be interested in such places, you know, I didn't know enough yet. 

I, I, I soon learned as history taught me something about socialism anyway. That, that was part of it. Part of it was political and personal. Personal. I had a, I had [00:27:00] actually sent letters for possible postdocs to three different labs and one of them in California where I heard back, but I didn't like the response, so I didn't pursue it. 

One of them in, uh, Mexico, somebody called Hernandez-Peon had a lab in Mexico. Uh, he was one of the co-discoverers of reticular activating stuff. He was very, very important in the early work on arousal systems. If you go back to the sixties, you'll find his name. I, so I applied to him as well. Unfortunately, he got killed in a car accident, even, you know, before I even heard back from him. 

So I didn't like the guy in California for reasons I I can go into later, doesn't matter. And his response was weird and I, and Bures said, sure. Get money and come. So that was it. I got money and I went basically just, I had never been west of the Mississippi. I grew up in New York, went to school in Montreal, had never been west of [00:28:00] the Mississippi River, and I got on a plane with my then wife and two little kids and went to Prague. 

My project that got me the money was, I was going to use techniques that Bures had developed for recording from single cells to try to do conditioning in individual neurons. I was gonna stimulate individual neurons in the hippocampus or cortex. I was also gonna stimulate or record in the hippocampus and in the hypothalamus to add reward in. 

I was gonna try to do conditioning at the neuronal single cell level. It was a great idea, but it was crazy. There's no way I was ever gonna be able to do that. By the way. I was way, way beyond my, my skills. In fact, what I found out when I got to the lab in Prague, it was way beyond the capacity of the lab to support technically that actual kind of experiment. 

I mean, they had handmade computers basically and they worked and you could do stuff. But anyway, [00:29:00] we quickly gave that up and I ended up going back to spreading depression and doing a whole bunch of very interesting experiments, mostly with Olga Buresova, who was his. Wife and partner in the lab. 

So, Bures and Buresova were a academic couple. He was the more famous one. She was the one who did a lot of the work in the lab. They both were famous and I worked with her. She was a fabulous person. They were, they're both dead now. They, they were, they became my ideal of what it meant to be an academic couple. How you could both be scientists and make it work personally, professionally, for the lab. 

Turns out not to be, you know, there've been some famous academic couples, even in, especially in the hippocampal world. Yeah. Yeah. I mentioned already Milner and Milner. Alright. And now the, you know, the Mosers, right? Barnes and McNaughton, right. Uhhuh, I mean, these are, Carol Barnes and Bruce McNaughton were a [00:30:00] couple for 30 years. 

So there've been some famous couples in this world. Very few of them made their personal thing work out by the way. But, you know, Bures and Buresova made it work and it was just wonderful to see, and they, they became my personal and professional mentors. Anyway, I did a lot of work with Buresova. She, she gave me a lot of advice about life and everything else. 

And I had a wonderful time doing research there on, on hemispheric transfer of memory, uh, techniques for training, for using, spreading depression to temporarily inactivate one hemisphere, training the animal so that they, whatever they learned would be restricted to the other hemisphere. Then washing away the spreading depression, so to speak. 

You know, clearing the brain, un deactivating, letting the brain go back to normal. And then seeing under what conditions does the information transfer to the other side. So how do you test if it transfers to the other side? You knock out the side you trained, [00:31:00] right? So if you knock out the one side you trained, if you train one side with this side knocked out and you train half of the brain, And you can do that in a rat, right? 

Because you can restrict the input into one eye and in the rat most of the input is contralateral. So you can restrict the input to one side, knock out one side, train the other side, let them recover, knock out the train side and just test the animal. It's as if they don't know anything, alright? However, if when you let the brain recover with half of the brain trained, if you give them a few trials, one or two trials with the brain, both sides intact, you get a transfer of the information to the other side. 

So we did a bunch of experiments looking at the conditions under which you get that kind of transfer. Basically, how many trials do you need? How often do you have. You know, whether the trials have to be correct trials or incorrect trials and so on. We, and we published a bunch of that, uh, one of, one of those [00:32:00] papers ended up in Nature, which was like, my second or third publication was a nature publication, and I've never been published in Nature since, or Science. 

I thought like, this is the way it works, but it wasn't the way it works. Anyway, so, so I did that work, it, you know, really loved it and, and, and had a, was living with my, my then wife and two little kids. The, the institute was, uh, was in a town which was just on the outskirts of, of Prague. It's now inside Prague City limits, but it was just on the outskirts of Prague in the Southwest a little bit. 

So it was a lovely place. Wasn't the city, but you could easily take a tram into the city. We were, you know, we were in town in 15 or 20 minutes, but it was a lovely place to live, and my kids had a great life, and the rural part of, you know, everything was hunky dory until the Russians invaded. Then it, then it got strange, right? 

So I was basically in, as it turns out, because [00:33:00] of where we lived, the Russian tanks that had been flown into Hungary to make it appear as though it was a Warsaw Pact invasion rather than a Russian or German invasion. They had tanks coming up from the south that those tanks came rolling right past my house, because we were on the southern route into the city with this little town. 

So I got, I woke up in the morning of August 20th, or 21st, 1968, and there were tanks coming up the road, you know, Russian tanks basically, and, and nobody thought it was gonna happen, but it happened. So now what do you do? I've got two little kids. They were at that point in time, this was 68. They were three and a half, and four and a half. 

They spoke check fluently better than English. And I, we, we really didn't know what to do basically. And, but Bures and Buresova said, you know, I cannot guarantee the [00:34:00] safety of your children. You should probably leave. So we packed, we had a Volkswagen camper that we had bought in Germany. We loaded up everything we owned and we drove out of what was then Czechoslovakia through tank columns to get outta the country. 

I suppose we should have felt in danger. I don't remember feeling in danger. We probably should have. Anyway, we got out and then we were in Austria, got in touch with my parents who were, we can imagine were, you know, quite concerned. Hadn't heard from us in those days. You know, you, there was no email, right? 

I mean, my parents and their two grandkids, you know, they had no idea whether they were safe or not. Anyway, we, and then what do we do? I said, well, there's only one person we know in Europe. John O'Keefe. So we drove, called up John and I said, John, can we come and stay with you for a while? I may, I may wanna shift my [00:35:00] research to London, if possible for the time being. 

And John says, sure, come on. So drove drove across Europe and decamped on John O'Keefe's doorstep in an apartment, which by the way, he still lives in the same apartment really. Okay. 1968. Right. So we, we showed up there and stayed there for a few weeks and then I got, I arranged to have my postdoc fellowship switched to University College London for one year in this psychology department, not in the anatomy department where John was. 

And I set up shop for some time in London for about eight months. And then I went back to Prague to finish my postdoc. When things settled, things had settled down. I went back cuz I loved it there and so on, but, During those eight months in, in London, John and I decided it would be kind of cool if we were in the same department. 

And, uh, cuz we kind of got on well and we, we kind of respected each [00:36:00] other's work, so to speak. I was not working on hippocampus at this point, nor was he at that point yet. And so we cooked up an arrangement where I would go back to Prague, finish my postdoc, and then I would come to London as a lecturer in the anatomy department. 

I had a job set up for me, so to speak. Then I would have a lab and all of that would be set up. So that's, I went back to Prague, did a bunch more experiments with Olga Buresova and publishing in various places. And then the end of my postdoc, I went to London to, uh, to take up a job at University College London, in the anatomy department in this, on the same floor, two doors down from John. 

And at that point, no place sells nothing yet. None of that had happened yet. 

Benjamin James Kuper-Smith: so that was what, like 1970 or  

Lynn Nadel: This was 1970. This was the summer of 1970. Now John, I think just beginning to work on hippocampus then, but the first place cell paper came out in 71. 

So at that point I had left, I had split up with my wife and uh, but I had my own, I had my kids, they were living with me and I was with another, in another relationship and I was in London at, I was then, my initial thought in going to that lab in London and what I set the lab up to do was to investigate the neurophysiology behind the inter-hemispheric transfer stuff that I had studied in Prague. 

I was gonna study the visual system and, you know, cross-talk between hemispheres under the conditions that I had looked at behaviorally. That was my plan for what I was gonna do in London. I was gonna work on visual system and learning in visual cortex and, and so on. And I got my lab set up and I had, you know, some of the same issues that I had when I tried to be a chemist. 

I wasn't necessarily great at independently setting up a lab, but I'm toodling away doing whatever I was doing. And John comes down the hall and says, yeah, have a look [00:38:00] at some data that I just got. And he showed me the data from the first few place cells, and I had done my PhD on the hippocampus. We skipped over that right in, in an attempt to understand, you know, the, the disjunct between animal and human results. 

In hippocampal research in the 1960s, the, the animal models were failing and people didn't understand why. I had a hypothesis my dissertation had attempted to test that hypothesis. It didn't work, doesn't matter. But I had done work on hippocampus and John knew that. He came down, said, well, you know, you, you've studied, you, you've been a hippocampal guy. 

Uh, what do you make of these cells? He didn't have to show me more than. You know, two minutes of data. I said, wow, that looks like spatial stuff, doesn't it? And he said, absolutely. Yeah, right, of course. Yeah. I mean, he knew it right and it was immediate, right? And I'd say within about 10 nanoseconds, my interest in the visual system evaporated. 

[00:39:00] And I, and John said, well, well we, and we joined forces basically. And he continued the unit work. I did a lot of behavioral work, lesion work, and we started to develop the theory together. You know, the basic idea, the hippocampus has these play cells, it's where Tolman's cognitive map must be, so to speak. 

And then we started to develop a theory, you know, about what would this mean, you know, if the hippocampus was that structure. And obviously it's also a memory structure. So that's interesting. And then can we, how far can we take this idea, you know, of the hippocampus as a cognitive map? I mean, that wasn't even, the book was just, Pipe dreams. 

There was no book idea yet. How can we take this notion that this is Tolman's cognitive map and use it to understand, you know, all the stuff that's out there about the hippocampus and use it to predict new things and to blah, blah, blah. You know, that kind of approach. And that's what led to the book. I mean, that, [00:40:00] that's what led to the, initially to the development of the theory. 

The idea that the hippocampus was the, was the core of a, a system that did cognitive mapping. And we initially, our concept at that point was we were gonna write a kind of a fairly long Psych Review paper, which was the place where you published theoretical papers in the 1960s and 1970s. If you were a psychologist, that was the only show in town. 

There were no Frontiers journals, there was no, you know, current opinion journals. None of that existed. If you had something to say, theoretically you published a paper in psych review. That was where Hull published his work. That was there to all it. That was it. Okay. So that was our plan. We were writing up the, we were writing up a kind of a chapter for, uh, for this, for a psych review paper. 

Now, of course, as you experienced, London is a place where a lot of people, famous people came to give talks. But one of the venues [00:41:00] for these talks was the Neurology, uh, institute. I guess it was then headed by Elizabeth Warrington. Now, cause Elizabeth Warrington was a major figure in memory research in the field. 

Warrington and Weiskrantz, I mean, she was a major kind of opponent of Brenda Milner. So here was me and John kind of brought up in the Milner tradition. Now we were dealing with Elizabeth Warrington, very friendly, a great relationship with Elizabeth, and she had talks all the time in. In the institute in Queens Square. 

You know where, you know where it this now  

Benjamin James Kuper-Smith: where Yeah. That's where it did thesis. Yeah.  

Lynn Nadel: That's where all the uc, that's where all the stuff happened. Where Eleanor and all those, all that, yep. Sort of difficult up there. But at that point, Queens Square was just where Elizabeth Warrington was with her seminars. 

And we would go to the seminar in the building there, and then afterwards we would go to Elizabeth's office in her little, one of those buildings on Queen Square. Same building, I think essentially. And we would have Sherry in her [00:42:00] office with the speaker with a few selected guests. And John and I were amongst the selected guests. 

We were pretty tight with Elizabeth because she was interested in hippocampus. Well, the speaker of this day was somebody, I'll tell you who it was and admitted if you care, but it was somebody whose name I didn't recognize. And he came in and he, and he sat behind Eli. He sat where Elizabeth normally sits, which set me off a little bit right away. 

And then he started to wax eloquent about what a liberated male he was. This was the period of female liberation in the US and he was the, he was going on about, and, and he, his wife was also an academic, but he, and, and I had, I was a fairly, um, intolerant person. I didn't put up with much bullshit in those days. 

Still don't. So I, you know, after listening to this for a while and after having two or three sherrys, I just lost it. And I just went [00:43:00] after this guy and told him, what an A -hole I mean, I just went, went after him big time. Um, and at which, and then, you know, said, that's it. I can't stand being in your presence. 

And me and John and John looking at me horrified. And then the two of us left, and then we were walking down Queens Square, you know, they have all these metal gates along Queens Square in front of the houses, walking down, holding. And John was holding on and John says, said to me, You know who that was, right? 

And I said, yeah, some jerk, you know, some jerk who thinks he's, you know, God's gift to women, something like that. And he said, no, no, no, that's the editor of Psych Review. 

And I said, oh, I see. Well that was the end of the plan to submit a paper to Psych review. So then we stepped back and said, okay, what could we do instead? So, well, why don't we write a monograph? You know, we can write a small monograph and we get all our ideas into a [00:44:00] monograph. And that's how the book got started. 

Basically, we, we said, we then launched into writing a more expanded version of the theory as a monograph. And the monograph just grew and grew and grew, and it went through a variety of versions, some of which we circulated to the broader public to get feedback on. And ultimately, that's what led to the book in 78. 

But six years from when we first started thinking about writing a book to when the book came out.  

Benjamin James Kuper-Smith: Yeah, I mean, I read somewhere, this might have been actually on the, on your master, on account, um, yeah. That, as you just mentioned, that it took like six years, um, of getting the book actually finished and sending it to colleagues for a review and all that kind of stuff. 

I mean, was that planned from the beginning? I mean, I assume not that it took that long, but like was it all, were the comments so critical that it took you lots of time to revise it or, or were you just doing other stuff or?  

Lynn Nadel: It's not so much that they were that critical, but I don't think when we first, I [00:45:00] don't think when we started, we realized how much we were biting off. 

You know? I mean, in the end, I mean, we didn't have to write a book that, you know, basically went into the philosophy, anatomy, physiology, behavior, neurology, neuropsych. We didn't have to do that. Not to mention going into the human case with language and uh, you know, there are substantial sections, but each one of those things, It took a lot of time, you know, to actually write that philosophy. 

We did. But at some point we decided, you know, we want to tell the whole story. You know, we want to, we don't, we don't just want to say why play cells are interesting and how they might make a cognitive map. We want to talk about why animals have cognitive maps in the first place. You know, why, why, why do they exist? 

You know, why do they exist? Why do they necessarily exist? What light do they shed on the way the the bigger brain works, so to speak? We were pretty, somewhere along the way, we thought that, you know, we, we had the potential to develop a theory that was, was sufficiently [00:46:00] multi-level, uh, and multi anchored in, in enough literature separately, each of which constrained, you know, what you can do within a theory that this might, we were thought, we were developing a model for how the cognitive neuroscience of the brain ought to work. 

We, we were quite. I mean, I think it's Ima I think, but we were conscious of the fact that we were, we were developing a kind of a model for how this emerging cognitive neuroscience should go. That, that if you were gonna talk about the function of the hippocampus, you had to talk about its anatomy and its physiology and it's, you had to do all of that if you wanted to have, and that was the way the, the field should develop. 

And we thought if we could crack the hippocampus and its structures that that could be the foundation for developing a kind of a cog neuro approach to the larger parts. You know? And I think by and large that it had its impact in that way. [00:47:00] So we didn't imagine it would take us six years when we got started, but we weren't surprised that it did once we kind of figured out what it is we wanted to do. 

Now in the midst of all of that, I was going through all kinds of personal turmoil in my relationship life. So I probably could have, I probably could have gotten my. Parts done earlier, but John was, you know, working away on the model. He was working away on the physiology. He was working away on the language stuff in humans cuz he had, so, you know, we were all just, we just kept moving the goalposts. 

I mean, it took that long because we kept on adding, you know, well, let's weigh in on this as well and let's add this bit and let's add that bit. I mean, we just, we'd had no idea. But again, in those days, I remember distinctly a discussion with John coming down the, the, uh, the stairwell of the anatomy department. 

If you've ever were in that lab in John's lab up on the fifth floor of the, of the anatomy building, and you walked down [00:48:00] these very old creaky stairs, and I'm walking down the stairs, I can remember it as if it was yesterday. And I'm saying to John, you know, John, it was 19 73, 19 74, something like that. I haven't published anything in three or four years, as in, in anything, after I had published a flurry of papers coming outta my Prague work. 

Nothing. I said, John, should, you know, should we be concerned that we're, that we're like, you know, will this, like, will we still have jobs? And John, you know, at this point, John was the stronger of us and he said, eh, don't worry about it. You know, it'll work out, don't worry. And, and, and the good news is we were in a department and we were at a time in the academic history when we could get, when we were allowed to get away with that, we were not in a publish or perish regime. 

We were protected by Pat Wall, whose unit we were in. He said, you guys are working on something important. Don't worry about it. Don't worry about the fact that you're not publishing. The [00:49:00] head of the department was JZ Young. JZ Young, very, very famous. The guy with the octopus work from the 1930s. 

Very, very famous neuro anatomist neuro. He, you look him up, JZ Young six-seven. Incredibly imposing kind of guy. He protected us. He also, so we were protected, we were allowed to take that time. We were allowed to develop our thinking. This, you know, I say to students now, I don't know if this could happen now. 

I, I don't know, under what conditions people would be allowed to do what we did to develop our ideas, not worry about publishing, not worry so much about getting grants, although we had grants to do some, do research and so on, and just go for it intellectually. I mean, that was a rare and lucky event basically, that we were, where we were. 

I mean, talk about, I go back to the theme of how lucky I was right. To be down the hall when John, you know? Right. Yeah, [00:50:00] yeah. Anyway,  

Benjamin James Kuper-Smith: I mean, w we would an approach today to do something like that be to instead publish, you know, each chapter as a separate paper and that way kind of, is that kind of the only way you can do it or. 

Lynn Nadel: Almost certainly. I mean, on the other hand, you, every so often people are publishing books, you know, some people are still taking that route. Uh, I don't know of another example, quite like the Cognitive Map book, but there are, there are people who are still doing it. Uh, again, I think that was in that era you could do that. 

We got away with it. We were lucky. Uh, it worked out well, but, uh, you know, it, it conditions now would, would make it much harder for us to do what we did then. But, so we took our time in the meet. I, I actually left London in, in 76 to move back to the States again, personal issues. Uh, and I continued working in the states, on the book, on the sections of the book, the human sections of the book that I was working on and all the behavioral stuff, all the chapters on behavior and for, and for, and John was continuing to work on the model and we were in constant contact. 

I started  

Benjamin James Kuper-Smith: this [00:51:00] last episode, um, but I want to have a few recurring questions that I asked, uh, that I ask every guest at the end of the episode. The first one is, what's a kind of paper or book that basically you think more people should read? Maybe it's something that used to be famous people forgot about it. 

Maybe it was never actually read widely, but should be. Um, yeah. Do you have anything there?  

Lynn Nadel: I mean, there's a couple. I, you know, I, I, I thought about that a little there a couple that I keep telling people. Have you read, did you ever read this paper? So I'll tell you the two that come to mind. One of them is by Stan Klein. 

It was about episodic memory and, and sort of, you know, why do we remember the episodic memories? We do Remember, we, you know, episodic memories is special zone. And it's quite clear that we don't remember all of our episodes. We only remember a small number of them. Why do we remember the ones we remember? 

Well, a lot of people think, you know, salience and whatever. There's a lot of answers to that question. Anyway, Klein wrote a paper, I think it was in 2001, may have been 2002, and it was in Psych Review. And the [00:52:00] note and the idea that he put forward in that paper was that we remember the exception cases that. 

For episodes that are kind of like other episodes in our life, we end up with a kind of a schematic, kind of semantic like memory for all of those episodes mushed together because they were all so similar. But if you have an, an episode that starts out like one of those but ends up being rather unique and quite different, that one you remember because that's an exception case and there might be something about that you need to know. 

You don't want that this to be mixed in with the statistics of all the others. So this is the, when you're not doing statistical learning about everything in the world, why do you keep a singular memory of a single thing that you don't subject to the statistics? Stan Klein had a view about that yet, and they wrote a paper on it. 

I think people, I think that was an important paper that people should pay attention to. Mm-hmm. Round and about the same time, Kali and Dayan, I can't remember the, the first name of the, [00:53:00] the Kali person. Uh, were, were working on, um, Sort of this question of if the hippocampus and the cortex are kind of talking to each other all the time, and they, and, you know, as a function of consolidation and if the memories in, and if cortex, according to the, the 1995, uh, complementary learning systems model, you know, McClelland, McNaughton, and O'Reilly model cortex is slowly being changed over time to accommodate new information. 

That means that if the hippocampus is connected to a particular set of nodes in the cortex, and the cortex is slowly evolving, how does the hippocampal index to that cortical stuff stay in, register with the cortical neurons if they are slowly changing, if the cortical engram is slowly changing, how does the hippocampus stay and register with it? 

So they identified that as a problem, a problem for how. Anyway, this, this came out of a paper, I think in [00:54:00] 2002 for Kali and Dayan. That's a paper I recommend to everybody to read. But very few people are aware of it because it really, that is a crucial problem. It's even more important now that we know that there's this representational drift in, in the hippocampus. 

So you got hippocampal representations that are drifting around. You got cortical representations that are drifting around. But everybody's theory requires that the hippocampus and the cortex be able to talk to each other in a meaningful way. How do they do that if they're both drifting? Anyway, that's a computational problem. 

And that paper is the first one that I'm aware of that identified that one more. Rao and Ballard, the, the first paper that really put the predictive, the predictive model, you know, on everybody's radar screen, another paper that people should really pay attention to, you know, and give credit to. So that's, that's a longish answer to,  

Benjamin James Kuper-Smith: um, Something that you wish you'd learned sooner? 

This can be from academia, [00:55:00] from your private life, basically whatever, some sort of error that you've repeated too often, maybe, maybe one or two times too often. Yeah, 

Lynn Nadel: that's a tough one. Uh, for me, it turns out, cuz I've al, I mean, probably should say, you know, I, I learned not to take myself too seriously, but I don't think I've ever taken myself too seriously. But I think I've learned what little seriousness I did invest in myself. I, I've learned with probably not such a good idea. 

So that would be one thing that's a, that's been more of a personal thing, my career thing. I mean, I, I guess I've learned, I, I've had such an unusual career and, and, you know, measured and been so lucky in, in so, in so many ways that I, I, I, I've learned not to, not to use my experience to give advice to others. 

Mm-hmm. Uh, It's not that I, and I don't mean that sort of, you know, in a bragging way that they, they couldn't replicate what I can do. [00:56:00] That's not the point at all. But just that the combination of things that got me to where I am is so unusual and so lucky that you, you can't count on that. I mean, so here's, here's the one. 

I'll give you one example, then move on. Something else. When I became department head, I was having to deal with people who were going up for tenure, you know, and the, and the anxiety and the difficulties and all, you know, I mean, what it's like to be in that situation under that pressure. I never did that. 

I, I was on soft money until I got hired at Arizona, when I was hired as a full professor with tenure. I never went through the tenure angst. I never had that experience. So when I was dealing with my faculty members, young colleagues who were, you know, going on about how hard this was and inside I couldn't, I never, I, I never felt what they felt and I, and so I, I didn't say, oh, don't, yeah, I, I, I learned to stop saying. 

Don't worry about it, not that big a deal, blah, blah, blah. Because it wasn't from me and I learned to not, you know, and that's just [00:57:00] an example for how I learned, you know, my, my experience is I shouldn't, I shouldn't imagine. You know, that I can give good advice to others to do, do it like I did it. Cuz that probably isn't such good advice in the end. 

Benjamin James Kuper-Smith: Yeah, yeah, yeah. Like the step one is miraculously be part of a go generation. Right, exactly. With one of the most influential psychologists. Yeah. Um,  

Lynn Nadel: find, find yourself in, you know, you know, as a graduate student in a place with a future Nobel Prize winner and a bunch of people who are the most famous people on the planet. 

That's step one. Go from there. Exactly. Yeah.  

Benjamin James Kuper-Smith: Okay. So I guess my last question of what you would re what you would recommend to someone maybe like me, a younger researcher in their PhD or early postdoc. Uh, so did you just answer that by saying you're not gonna do that? Uh,  

Lynn Nadel: no. That I could do. Cause I think in terms of the ideas about what would be interesting to work on, that's a. 

It's not like, don't, not like, don't do it my way. And I, I think quite honestly [00:58:00] right now, that I, I think this first of all, this shift to the kind of predictive model of the brain and how that works. I mean, to me that's, you know, where the action is now, the Bayesian approach, all this is about having priors. 

How does, how does the brain do that? And, and I think in particular, memory has gotten quite memory. Research again has gotten quite exciting because, you know, people are really, you know, pushing on dynamical models of memory. So I would say to people who were just getting started, first of all, and I, I asked this question of Brenda Milner and she, her answer to this question was, learn all the new techniques. 

So I think the first thing is you gotta familiarize yourself with new, with the new technologies and what, what can be. You don't have to be an expert at them because nobody can be, but you gotta, you have to be aware of what, what, you know, what are the possibilities, what kinds of questions can actually be approached empirically. 

Now, the kinds of questions that we were talking about with Konorski back in the 1960s about, we wanna know why these neurons, but not that, but, but not those neurons, you know, show learning. [00:59:00] We all said at that point, we can't ask those kind of questions empirically now, now we can. Right. So understand what's possible, technolo, technically, and then what are the big questions in the field. 

Think about big questions. Ev it's great to get caught up in your answering a specific question, but what's the big question you're interested in? Have such a big question in your mind, even if you're working on a small thing. For me, the big question is just how do memories get modified continuously? 

What's the, what's the dynamical way in which prediction error, and all of that interacts in a way to so that our memories are constantly being updated so that they're more adaptive. That's to me exciting and I would recommend that to anyone who was looking for a specific question to be excited about. 

But there's a lot of other ones. I mean, the field is, there's a really a lot of good stuff out there now, and the tech, the techniques that are available make it possible to do some pretty fascinating experiments. But here's the [01:00:00] big but, but you must pay attention to the behavior of the animal you're studying. 

Don't get stuck using super cool technology on stone age, behavioral tech, you know, paradigms because then you'll end up saying this stupid stuff. Your understanding of the behavior and the role of that behavior in the ecological niche of that animal is as important as your understanding of the technology you're, you're using, which looks really fancy. 

And, and I'll close on this is why O'Keefe discovered place. He had trained with a behaviorist. He had trained with an ethologist Danny Lehrman. He had worked in a lab wi with the importance of paying attention to the ecologically important aspects of an animal's behavior was drilled into him even before he became a graduate student. 

As a graduate student. He spent his time trying to develop ways to record from single cells in the amygdala of a freely moving animal. That was what he did in graduate school, he was ready to start working on freely moving rats in hippocampus. And he was aware of the importance of doing it in a way that the animal could move around in the world. 

So he had to solve the problem of, of movement artifact. Once he solved the problem of movement artifact with field effect transmitters on the animal's head, which is what he did in the early work. I mean all of this preceded tetrodess and all that kind of thing. Once he solved that problem and the animals could move around in the world, voila, place, cells were obvious. 

So the lesson here for the students is, Be as sophisticated about your understanding of behavior and about the ecological aspects of that behavior for the animal you're studying as you are about technology. And then bring big questions to that knowledge and guess what you'll do. Well, that would be my advice.

How Lynn went from studying chemistry to doing a PhD on memory
What was it like working Donald Hebb?
The golden era of cognitive neuroscience at McGill in the 50s and 60s
Lynn's postdoc in Czechoslovakia was interrupted by the Soviet invasion during Prague Spring
The discovery of place cells and the writing of The Hippocampus as a Cognitive Map
A paper or book Lynn thinks more people should read
Something Lynn wishes he'd learnt sooner
Advice for early career scientists