The following is a conversation with Andrew Huberman, a neuroscientist at Stanford,

working to understand how the brain works, how it can change their experience,

and how to repair brain circuits damaged by injury or disease.

He has a great Instagram account at Huberman Lab, where he teaches the world about the brain

and the human mind. Also, he's a friend and an inspiration in that he shows that you can be

humble, giving, and still succeed in the science world. Quick mention of each sponsor,

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was more critical on occasion than I meant to be, didn't push on certain points that I should have,

was undereducated or completely unaware about some major things that happened in the past,

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Friedman. And now, here's my conversation with Andrew Huberman. You've mentioned that in your

lab at Stanford, you do stress by putting people into virtual reality and having them go through

one of a set of experiences. I think you mentioned this on Rogan or with Whitney,

that scare them. So just on a practical, psychological level and maybe on a philosophical

level, what are people afraid of? What are the fears? What are these fear experiences that

you find to be effective? Yeah, so it depends on the person, obviously. And we should probably

define fear, right? Because you can, without going too far down the rabbit hole of defining

these things, you can't really have fear without stress, but you could have stress without fear.

And you can't really have trauma without fear and stress, but you could have fear and stress

without trauma. So we can start playing the word game, and that actually is one of the

motivations for even having a laboratory that studies these things is that we really need better

physiological, neuroscientific, and operational definitions of what these things are. I mean,

the field of understanding emotions and states, which is mainly what I'm interested in,

is very complicated. But we can do away with a lot of complicated debate and say,

in our laboratory, what we're looking for to assign it a value of fear is a big inflection

in autonomic arousal. So increases in heart rate, increases in breathing,

perspiration, pupil dilation, all the hallmark signature features of the stress response.

And in some cases, we have the benefit of getting neurosurgery patients where we've got

electrodes in their amygdala and their insula and the orbital frontal cortex down beneath the skull.

So these are chronically implanted electrodes, we're getting multiunit signals. And we can start

seeing some central features of meaning within the brain. And what's interesting is that

as trivial as it might seem in listening to it, almost everybody responds to heights and falling

from a high virtual place with a very strong stress, if not fear response. And that's because

the visual vestibular apparatus, the optic flow and how it links to the balanced semicircular

canals in the inner ears, all this technical stuff. But really, all of that pulls all your

physiology, the feeling that your stomach is dropping, the feeling that suddenly you're

sweating even though you're not afraid of falling off this virtual platform, but you feel as if

you're falling because of the optic flow, that one is universal. So we've got a dive with Great

White Sharks experience where you actually exit the cage. We went out into this in the real world

and brought back 360 video that's built out pretty. Oh, so this is actually 360 video?

360 video. And this was important to us, right? So when we decided to set up this platform,

a lot of the motivation was that a lot of the studies of these things in laboratories, I don't

want to call them lame because I want to be respectful of the people that did this stuff

before, but they'd study fear by showing subjects a picture of a bloody arm or a snake or something

like that. And it just, unless you have a snake phobia, it just wasn't creating a real enough

experience. So we need to do something where people aren't going to get injured, but where we

can tap into the physiology and that thing of presence of people momentarily, not the whole

time, but momentarily forgetting they're in a laboratory. And so heights will always do it.

And I, if people want to challenge me on this, I like to point to that movie Free Solo,

which was wild because, you know, it's incredible movie, but I think a lot of its popularity can

be explained by a puzzle, which is you knew he was going to live when you walked in the theater

or you watched it at home. You knew before that he survived. And yet it was still scary

that people somehow were able to put themselves into that experience or into Alex's experience

enough that they, they were concerned or worried or afraid at some level. So heights always does it.

If we get people who have generalized anxiety, these are people who

wake up and move through life at a generally higher state of autonomic arousal and anxiety,

then we can tip them a little bit more easily with things that don't necessarily get everyone afraid,

things like claustrophobia, public speaking, that's going to vary from person to person.

And then if you're afraid of sharks, like my sister, for instance, afraid of sharks,

she won't even come to my laboratory because there's, there's a thing about sharks in it.

That's how terrified some people are of these specific stimuli, but heights get some every time.

And I'm terrified of heights. It's, you know, when we have you step off a platform,

virtual platform, and it's a flat floor in my lab, but we, you're up there.

Well, you actually allow them the possibility in the virtual world to actually take the leap

of faith. Yeah, maybe I should describe a little bit of the experiment. So without giving away too

much in case someone wants to be a subject in one of these experiments, we have them playing

a cognitive game. It's a simple lights out kind of game where you're pointing a cursor and turning

out lights on a grid, but it gets increasingly complex and it speeds up on them. And, you know,

there's a failure point for everybody where they just can't make the motor commands fast enough.

And then we surprise people essentially by placing them virtually all of a sudden,

they're just, they're on a narrow platform between two buildings. And then we encourage them or we

cue them with a, with talking to them through a microphone to continue across that platform to

continue the game. And, you know, some people, they just won't, they actually will hold, get down

on the ground and hold on to a virtual beam that doesn't even exist on a flat floor. And so what

this really tells us is the power of the brain to enter these virtual states as if they were real.

And we really think that anchoring the visual and the vestibular, the balance

components of the nervous system are what bring people into that presence so quickly. There's

also the potential and we haven't done this yet to bring in 360 sound. So the reason we did 360

video is that when we started all this back in 2016, a lot of the VR was pretty lame, frankly,

it was CGI. It just wasn't real enough. But with 360 video, we knew that we could get people into

this presence where they think they're in a real experience more quickly. And our friend,

Michael Muller, who I was introduced to because of the project I reached out to some friends,

Michael Muller is a very famous portrait photographer in Hollywood, but he dives with

great white sharks and he leaves the cage. And so we worked with him to build a 360 video apparatus

that we could swim underwater with, went out to Guadalupe Island, Mexico, and actually got the

experience. It was a lot of fun. There were some interesting moments out there of danger,

but it came back with that video and built that for the sharks. And then we realized,

we need to do this for everything. We need to do it for heights. We need to do it for public

speaking, for claustrophobia. And what's missing still is 360 sound, where 360 sound would be,

for instance, if I were to turn around and there was a giant attack dog there,

the moment I would turn around and see it, the dog would growl. But if I turn back toward you,

then it would be silent. And that brings a very real element to one's own behavior,

where you don't know what's going to happen if you turn a corner. Whereas if there's a dog growling

behind me and I turn around and then I turn back to you and it's still growling, that might seem

like more of an impending threat and sustained threat. But actually, it's when you start linking

your own body movements to the experience. So when it's closed loop, where my movements and choices

are starting to influence things and they're getting scarier and scarier, that's when you can

really drive people's nervous system down these paths of high states of stress and fear. Now,

we don't want to traumatize people, obviously, but we also study a number of tools that allow

them to calm themselves in these environments. So the short answer is height.

Height? Yeah. Well, from a psychology and from a neuroscience perspective,

this whole construction that you've developed is fascinating. We did this a little bit with

autonomous vehicles. So to try to understand the decision making process of a pedestrian when they

cross the road and trying to create an experience of a car that can run you over. So there's the

danger there. I was so surprised how real that whole world was. And the graphics that we built

wasn't ultra realistic or anything, but I was still afraid of being hit by a car. Everybody we

tested were really afraid of being hit by that car. Even though it was all a simulation. It was

all a simulation. It was kind of a boxy, actually. I mean, it wasn't like ultra realistic simulation.

It's fascinating. Looms and heights. So any kind of depth, we're just programmed to not necessarily

recoil, but to be cautious about that edge and that depth. And then looms, things coming at us

that are getting larger. There are looming sensing neurons even in the retina at a very,

very early stage of visual processing. And incidentally, the way Mueller and folks learned

how to not get eaten by great white sharks when you're swimming outside the cage is as they start

lumbering in, you swim toward them. And they get very confused when you loom on them because

clearly you're smaller. Clearly they could eat you if they wanted to. But there's something about

forward movement toward any creature that that creature questions whether or not it would be a

good idea to generate forward movement toward you. And so that's actually the survival tool of these

cage exit white shark divers. Are you playing around with like one of the critical things for

the autonomous vehicle research is you couldn't do 360 video because there's a game theoretic.

There's an interactive element that's really necessary. So maybe people realize this. Maybe

they don't. But 360 video, you obviously, well, it's actually not that obvious to people, but you

can't change the reality that you're watching. That's right. But you find that that's like,

is there something fundamental about fear and stress that the interactive element is essential for?

Or do you find you can you can arouse people with just the video? Great question. It works best to

use mixed reality. So we have a snake stimulus. I personally don't like snakes at all. I don't

mind spiders. We also have a spider stimulus. But like snakes, I just don't like them. There's

something about the the slithering and the it just creates a visceral response for me.

Some people not so much. And they have lower levels of stress and fear in there. But one way

that we can get them to feel more of that is to use mixed reality, where we have an actual physical

bat, and they have to stomp out the snake as opposed to just walk to a little safe corner,

which then makes the snake disappear. That tends to be not as stressful as if they have a physical

weapon. And so you've got people in there, you know, banging on the floor against this thing.

And there's something about engaging that makes it more of a more of a threat. Now,

I should also mention we we always get the subjective report from the subject of what

they experienced because I we never want to project our own ideas about what they were feeling.

But that's the beauty of working with humans is you can ask them how they feel.

Exactly. And humans aren't great at explaining how they feel. But it's a lot easier to understand

what they're saying than a mouse or a macaque monkey is saying. So it's the best we can do

is language plus these physiological and neurophysiological signals.

Is there something you've learned about yourself about your deepest fears?

Like you said snakes, is there something that like if I were to torture you,

I'm so I'm Russian. So, you know, I always kind of think, how can I murder this people that this

person entered the room? But also, how can I torture you to get some information out of you?

What would I go with? It's interesting, you should say that I never considered myself claustrophobic.

But because I don't mind small environments provided they're well ventilated. But before

COVID, I started going to this Russian Banya, you know, and then we jumped here. And I had never

been to a Banya. So, you know, the whole experience of really, really hot sauna. And what are they

called the plots? They're hitting you with the leaves. And it gets really hot and humid in there.

And there were a couple of times where I thought, okay, this thing is below ground.

It's in a city where there are a lot of earthquakes. Like if this place crumbled and we were stuck in

here, and I'd start getting a little panicky, and I realized I'm like, I don't like small confined

spaces with poor ventilation. So I realized I think I have some claustrophobia. And I wasn't

aware of that before. So I put myself into our own claustrophobia stimulus, which involves getting

into an elevator. And with a bunch of people, virtual people, and the elevator gets stalled.

And at first, you're fine, you feel fine. But then as we start modulating the environment,

and we actually can control levels of oxygen in the environment if we want to,

it is really uncomfortable for me. And I never would have thought, you know, I fly,

I'm comfortable in planes, but it is really uncomfortable. And so I think I've unhatched

a bit of a claustrophobia. Yeah. Yeah, for me as well, probably. That one, that one's pretty bad.

The heights, I tried to overcome. So I went to skydiving to try to overcome the fear of heights,

but that didn't help. Did you jump out? Yeah, jump out. But it was, it was a,

it was fundamentally different experience. And I guess there could be a lot of different

flavors of fear of heights, maybe. But the one I have didn't seem to be connected to jumping

out of a plane. It's a very different, because like once you accept that you're going to jump,

then it's, it's a different thing. I think what I'm afraid of is the moments before it

is the scariest part. Absolutely. And I don't think that's emphasized in the skydiving experience

as much. And also just the acceptance of the fact that it's going to happen. So once you accept it

is going to happen, it's not as scary. It's the fact that it's not supposed to happen. And it might,

that's the scary part. I guess I'm not being eloquent in this description, but there's something

about skydiving that was actually philosophically liberating. I was, I was like, wow, it, it was

the possibility that you can walk on a surface. And then at a certain point, there's no surface

anymore to walk on. And it's all of a sudden the world becomes three dimensional. And there's this

freedom of floating that the concept of like, of earth disappears for a brief few seconds. I don't

know. That was, that was wild. That was wild, but I'm still terrified of heights. So I mean, one,

one thing I want to ask just on fear, because it's so fascinating is, have you

learned anything about what it takes to overcome fears? Yes. And that comes from two, from a,

you know, research study standpoint, two parallel tracks of research. One was done actually in mice,

because we have a mouse lab also where we can probe around in different brain areas and try

and figure out what interesting brain areas we might want to probe around in humans. And

a graduate student in my lab, she's now at Caltech, Lindsey Salay, published a paper back

in 2018 showing that what at first might seem a little bit obvious, but the mechanisms are not,

which is that there are really three responses to fear. You can pause, you can freeze essentially.

You can retreat, you can back up, or you can go forward. And there's a single hub of neurons

in the midbrain, in the, just actually not the midbrain, but it's in the middle of the thalamus,

which is a forebrain structure. And depending on which neurons are active there, there's a much

higher probability that a mouse or it turns out or a human will advance in the face of fear,

or will pause or will retreat. Now, that just assigns a neural structure to a behavioral phenomenon.

But what's interesting is that it turns out that the lowest level of stress or autonomic arousal

is actually associated with the pausing and freezing response. Then as the threat becomes

more impending, and we used visual looms in this case, the retreat response has a slightly higher

level of autonomic arousal and stress. So think about playing hide and go, seeking or trying to

stay quiet in a closet that you're hiding. If you're very calm, it's easy to stay quiet and

still. As your level of stress goes up, it's harder to maintain that level of quiet and stillness.

You see this also in animals that are stalking, a cat will chatter its teeth. That's actually

sort of top down inhibition and trying to restrain behavior. So the freeze response

is actually an active response, but it's fairly low stress. And what was interesting to us is that

the highest level of autonomic arousal was associated with the forward movement toward

the threat. So in your case, jumping out of the plane. However, the forward movement in the face

of threat was linked to the activation of what we call collateral, which means just a side

connection, literally a wire in the brain that connects to the dopamine circuits for reward.

And so when one safely and adaptively, meaning you survive, moves through a threat or toward a

threat, it's rewarded as a positive experience. And so the key, it actually maps very well the

cognitive behavioral therapy and a lot of the existing treatments for trauma is that you have

to confront the thing that makes you afraid. So otherwise, you exist in this very low level of

reverbitory circuit activity where the circuits for autonomic arousal are humming and they're

humming more and more and more. And we have to remember that stress and fear and threat were

designed to agitate us so that we actually move. So the reason I mention this is I think a lot

of times people think that the maximum stress response or fear response is to freeze and to

lock up. But that's actually not the maximum stress response. The maximum stress response is to

advance, but it's associated with reward. It has positive valence. So there's this kind of,

everyone always thinks about the bell shape curve for at low levels of rousal performance is low.

And as the increases performance goes higher, and then it drops off as you get really stressed.

But there's another bump further out that's distribution where you perform very well under

very high levels of stress. And so we've been spending a lot of time in humans and in animals

exploring what it takes to get people comfortable to go to that place. And also to let them experience

how there are heightened states of cognition there. There's changes in time perception that

allow you to evaluate your environment at a faster frame rate, essentially. This is the

matrix as a lot of people think of it. But we tend to think about fear as all the low level

stuff where things aren't worked out. But there are many, there are a lot of different features

to the fear response. And so we think about it quantitatively and we think about it from a circuit

perspective in terms of outcomes. And we try and weigh that against the threat. So we never want

people to put themselves in unnecessary risk. But that's where the VR is fun, because you can push

people hard without risk of physically injuring them. And that's a, like you said, the little

bump that that seems to be a very small fraction of the human experience, right? So it's kind of

fascinating to study it. Because most of us move through life without ever experiencing that kind

of focus. Well, everything's in a peak state there. I really think that's where optimal

performance lies. There's so many interesting words here. But what's performance? And what's

optimal performance? We're talking about mental ability to what, to perceive the environment

quickly, to make actions quickly. What's optimal performance? Yeah, well, it's very subjective

and it varies depending on task and environment. So one way we can make it a little bit more

operational and concrete is to say, there is a sweet spot, if you will, where the level of

internal autonomic arousal, aka stress or alertness, whatever you want to call it, is ideally matched

to the speed of whatever challenge you have to be facing in the outside world. So we all have

perception of the outside world as exteroception and the perception of our internal real estate

interoception. And when those two think when interoception and exteroception are matched

along a couple dimensions, performance tends to increase or tends to be in an optimal range.

So for instance, if you're, I don't play guitar, but I know you play guitar. So let's say you're

trying to learn something new on the guitar. I'm not saying that being in these super high

states of activation are the best place for you to be in order to learn. It may be that your internal

arousal needs to be at a level where your analysis of space and time has to be well matched to the

information coming in and what you're trying to do in terms of performance, in terms of playing

chords and notes and so forth. Now, in these cases of high threat where things are coming in quickly

and animals and humans need to react very quickly, the higher your state of autonomic arousal, the

better because you're slicing time more finely just because of the way the autonomic system works,

the pupil dilation, for instance, and movement of the lens essentially changes your optics.

That's obvious. But with the change in optics is a change in how you bend time and slice time,

which allows you to get more frames per second readout. With the guitar learning, for instance,

it might actually be that you want to be almost sleepy, almost in a kind of drowsy state to be

able to, and I don't play music, so I'm guessing here, but sense some of the nuance in the chords

or the ways that you're to be relaxed enough that your fingers can follow an external cue. So

matching the movement of your fingers to something that's pure extra reception. And so there is no

perfect autonomic state for performance. This is why I don't favor terms like flow because

they're not well operationally defined enough. But I do believe that optimal or peak performance

is going to arise when internal state is ideally matched to the space time features of the external

demands. So there's some slicing of time that happens, and then you're able to adjust a slice

time more finely or more or less finely in order to adjust to the stimulus, the dynamics of the

stimulus. What about the the realm of ideas? So like, you know, I'm a big believer, this guy named

Cal Newport who wrote a book about deep work. Yeah, I love that book. Yeah, he's great. I mean,

one of the nice things, I've always practiced deep work, but it's always nice to have words

put to the concepts that you've practiced. It somehow makes them more concrete and allows

you to get better. It turns it into a skill that you can get better at. But, you know, I also value

deep thinking, where you think it's almost meditative, you think about a particular concept

for long periods of time, the programming you have to do that kind of thing for, you just have to

hold this concept, like, like you hold it, and then you take steps with it, you take further

steps, and you're holding relatively complicated things in your mind as you're thinking about them.

And there's a lot of, I mean, the hardest part is there's a frustrating things like you take a step,

but it turns out to be the wrong direction. So you have to calmly turn around and take a step back,

and then it's you kind of like exploring through the space of ideas. Is there something about

your study of optimal performance that could be applied to the act of thinking,

as opposed to action? Well, we haven't done too much work there, but I think I can comment on it

from a neuroscience perspective, which is really all I do is, well, we do experiments in the lab,

but looking at things through the lens of neuroscience. So what you're describing can be

mapped fairly well to working memory, just keeping things online and updating them as they change

in information that's coming back into your brain. Jack Feldman, who I'm a huge fan of and

fortunate to be friends with, is a professor at UCLA, works on respiration and breathing,

but he has a physics background. And so he thinks about respiration and breathing in terms of

ground states and how they modulate other states, very, very interesting and I think,

important work. Jack has an answer to your question. So I'm not going to get this exactly

right because this is lifted from a coffee conversation that we had about a month ago.

So apologies in advance, but I think I can get it mostly right. So we were talking about this,

about how the brain updates cognitive states depending on demands and thinking in particular.

And he used an interesting example, I'd be curious to know if you agree or disagree.

He said, most great mathematics is done by people in their late teens and 20s, even you

could say early 20s, sometimes into the late 20s, but not much further on. Maybe I just

insulted some mathematicians. No, that's true. And I think that it demands, his argument was

there's a tremendous demand on working memory to work out theorems in math and to keep a number

of plates spinning, so to speak, mentally and run back and forth between them, updating them.

In physics, Jack said, and I think this makes sense to me too, that there's

a reliance on working memory, but an increased reliance on some sort of deep memory and deep

memory stores, probably stuff that's moved out of the hippocampus and forebraining into the cortex

and is more some episodic and declarative stuff. But really, so you're pulling from your library,

basically, it's not all RAM, it's not all working memory. And then in biology,

and physicists tend to have very active careers into their 30s and 40s and 50s and so forth,

sometimes later. And then in biology, you see careers that have a much longer arc,

kind of these protracted careers often, people still in their 60s and 70s doing really terrific work.

Not always doing it with their own hands because people in the labs are doing them, of course,

but and that work does tend to rely on insights gained from having a very deep knowledge base

where you can remember a paper or maybe a figure in a paper, you could go look it up if you wanted

to, but it's very different than the working memory of the mathematician. And so when you're

talking about coding or being in that tunnel of thought and trying to iterate and keeping a lot

of plate spinning, it speaks directly to working memory. My lab hasn't done too much of that.

Working memory. But we are pushing working memory when we have people do things like

these simple lights out tasks while they're under, we can increase the cognitive load

by increasing the level of autonomic arousal to the point where they start doing less well.

And, you know, everyone has a cliff. This is what's kind of fun. We've had, you know,

seal team operators come to the lab, we have people from other units in the military, very,

you know, we've had a range of of intellects and backgrounds and all sorts of things and

everyone has a cliff. And those cliffs sometimes show up as a function of the demands of speed

of processing or how many things you need to keep online. I mean, we're all limited at some

point in the number of things we can keep online. So what you're describing is very interesting

because it I think it has to do with how narrow or broad the information set is because and I don't

program I'm not an active programmer. So this is a regime I don't really fully know. So I don't

want to comment about it in that in any way that, you know, doesn't suggest that. But I think that

what you're talking about is top down control. So this is prefrontal cortex, keeping every bit

of reflexive circuitry at bay, the one that makes you want to get up and use the restroom,

the one that makes you want to check your phone, all of that, but also running these

anterior thalamus to prefrontal cortex loops, which we know are very important for working

memory. Yeah, let me try to think through this a little bit. So reducing the process of thinking

to working memory access is tricky. He's probably ultimately correct. But if I were to say some

of the most challenging things that an engineer has to do, and a scientific thinker, I would say

it's kind of depressing to think that we do that best in our 20s. But is this kind of first

principles thinking step of saying you you're accessing the things that you know, and then

saying, Well, let me how do I do this differently than I've done it before this this weird like

stepping back like, is this right? Let's try it this other way that that's the most

mentally taxing step is like, you've gotten quite good at this particular pattern of how you solve

this particular problem. So there's a there's a pattern recognition first, you're like, Okay,

I know how to build a thing that solves this particular problem in programming, say,

and then the question is, but can I do it much better? And I don't know if that's

I don't know what the hell that is. I don't know if that's accessing working memory.

That's that's almost access. Maybe it is accessing memory in a sense is trying to find

similar patterns in a totally different place that could be projected onto this.

But you're you're it's you're not querying facts, you're querying, like, functional things, like,

yes, patterns, I mean, you're running out, you're testing algorithms. Yeah, right,

you're testing algorithms. So I want to just because I know some of the people listening

to this and you how have basis in, you know, scientific training and have scientific training.

So I want to be clear, I think we can be correct about some things like the role of working memory

in these kinds of processes without being exhaustive. We're not saying they're the only thing

we're not, you know, we can be correct, but not assume that that's the only thing involved.

Right. And I mean, neuroscience, let's face it is still in its infancy. I mean, we probably

know 1% of what there is to know about the brain. You know, we've learned so much. And yet,

there may be global states that underlie this that make prefrontal circuitry work differently

than it would in a in a different regime, or even time of day. I mean, there's a lot of mysteries

about this. But so I just want to make sure that we sort of are we're aiming for precision

inaccuracy, but we're not going to be exhaustive. So there's a difference there. And I think,

you know, sometimes in the vastness of the internet, that gets forgotten.

So the other is that, you know, we think about, you know, we think about these operations at,

you know, really focused keeping a lot of things online. But what you were describing is actually

it, it speaks to the very real possibility probably that with certainty, there's another

element to all this, which is when you're trying out lots of things, in particular,

lots of different algorithms, you don't want to be in a in a state of very high autonomic

arousal. That's not what you want, because the higher level of autonomic arousal and stress in

the system, the more rigidly you're going to analyze space and time. Right. And what you're

talking about is playing with space time dimensionality. And I want to be very clear. I mean,

I'm the son of a physicist. I am not a physicist. When I talk about space and time, I'm literally

talking about visual space and how long it takes for my finger to move from this point to this point.

You are facing a tiger and trying to figure out how to avoid being eaten by the tiger.

And that's primarily going to be determined by the visual system in humans. We don't walk

through space, for instance, like a sent hound would and look at three dimensional sent plumes.

You know, when a sent hound goes out in the environment, they have depth to their odor

trip, the odor trails they're following. And they don't think about them. We don't think about odor

trails. You might say, Oh, well, the smell is getting more intense. Aha. But they actually

have three dimensional odor trails. So they see a cone of odor, see, of course, with their nose,

with their olfactory cortex. We do that with our visual system. And we parse time often

subconsciously, mainly with our visual system, also with our auditory system. And this shows up

for the musicians out there, metronomes are a great way to play with this, you know, base

drumming, when the frequency of base drumming changes, your perception of time changes quite

a lot. So in any event, space and time are linked in that through the sensory apparatus,

through the eyes and ears and nose, and probably through taste to and through touch

for us, but mainly through vision. So when you drop into some coding or iterating through a

creative process or trying to solve something hard, you can't really do that well if you're in a rigid

high level of autonomic arousal, because you're plugging in algorithms that are

in this space regime, this time regime matches at space time matched, whereas creativity,

I always think the lava lamp is actually a pretty good example, even though it has these

counterculture, new agey connotations, because you actually don't know which

direction things are going to change. And so in drowsy states, sleeping and drowsy states,

space and time become dislodged from one another somewhat, and they're very fluid. And I think

that's why a lot of solutions come to people after sleep and naps. And this could even take us into

a discussion, if you like, about psychedelics. And what we now know, for instance, that people

thought that psychedelics work by just creating spontaneous bursting of neurons and hallucinations,

but that the 5H2C and 2A receptors, which are the main sites for things like LSD and

psilocybin and some of the other ones that create hallucinations, the drugs that create hallucinations,

the most of those receptors are actually in the collection of neurons that encase the thalamus,

which is where all the sensory information goes into, a structure called the thalamic

reticular nucleus. And it's an inhibitory structure that makes sure that when we're

sitting here talking, that I'm mainly focused on whatever I'm seeing visually, that I'm

essentially eliminating a lot of sensory information under conditions where people take

psychedelics and these particular serotonin receptors are activated, that inhibitory shell,

it's literally shaped like a shell, starts losing its ability to inhibit the passage of

sensory information. But mostly, the effects of psychedelics are because the lateral connectivity

in layer five of cortex across cortical areas is increased. And what that does is that means

that the spacetime relationship for vision, like moving my finger from here to here, a very rigid

spacetime relationship, if I slow it down, it's slower, obviously, but there's a prediction

that can be made based on the neurons in the retina and the cortex. On psychedelics, this

could be very strange experience. But the auditory system has one that's slightly different

spacetime and they're matched to one another in deeper circuits in the brain. The olfactory

system has a different spacetime relationship to it. So under conditions of these

increased activation of these serotonin receptors, spacetime across sensory area starts

being fluid. So I'm no longer running the algorithm from moving my finger from here to here and

making a prediction based on vision alone. I'm now, this is where people talk about hearing

sites, right? You start linking, this might actually make a sound in a psychedelic state.

Now, I'm not suggesting people run out and do psychedelics because it's very disorganized.

But essentially what you're doing is you're mixing the algorithms. And so when you talk about being

able to access new solutions, you don't need to rely on psychedelics. If people choose to do that,

that's their business. But in drowsy states, this lateral connectivity is increased as well.

The shell of the thalamus shuts down. And what's happening is you're getting whole

brain activation at a level that you start mixing algorithms. And so sometimes I think

solutions come not from being in that narrow tunnel of spacetime and strong activation of

working memory and trying to iterate if this, then that's very strong, deductive and inductive

thinking and working from first principles, but also from states where something that was

an algorithm that you never had in existence before suddenly gets lumped with another algorithm.

And all of a sudden, a new possibility comes to mind. And so space and time need to be fluid and

space and time need to be rigid in order to come up with something meaningful. And I realize I'm

riffing long on this. But this is why I think there was so much interest a few years ago with

Michael Pollan's book and other things happening about psychedelics as a pathway to exploration

and all this kind of thing. But the real question is what you export back from those experiences.

Because dreams are amazing. But if you can't bring anything back from them, they're just amazing.

I wonder how to experiment with a mind without any medical assistance first.

I pushed my mind in all kinds of directions. I definitely want to, I did shrooms a couple of

times. I definitely want to figure out how I can experiment with psychedelics. I'm talking to Rick

Dobin, I think. Doblin. Doblin. Soon. I went back and forth. So he does all these studies on

psychedelics. And he keeps ignoring the parts of my email that asks, like, how do I participate in

these studies? There are some legality issues. I mean, conversation, I want to be very clear.

I'm not saying that anyone should run out and do psychedelics. I think that drowsy states and

sleep states are super interesting for accessing some of these more creative states of mind.

Hypnosis is something that my colleague David Spiegel, Associate Chair of Psychiatry at Stanford,

works on. Where also, again, it's a unique state because you have narrow context. So this is very

kind of tunnel vision and yet deeply relaxed where new algorithms, if you will, can start to surface.

Strong state for inducing neuroplasticity. And I think, so if I had a, I'm part of a group

that it's called the liminal collective as a group of people that get together and talk about

just wild ideas, but they try and implement. And it's a really interesting group, some people from

military, from Logitech and some other backgrounds, academic backgrounds. And I was asked, what would

be if you could create a tool, if you just had a tool like your magic wand wish for the day,

what would it be? I thought it'd be really interesting if someone could develop psychedelics

that have on off switches. So you could go into a psychedelic state very deeply for 10 minutes,

but you could launch yourself out of that state and place yourself into a linear real world state

very quickly so that you could extract whatever it was that happened in that experience and then go

back in if you wanted. Because the problem with psychedelic states and dream states is that,

first of all, a lot of the reason people do them is they're lying. They say they want plasticity

and they want all this stuff. They want a peak experience inside of an amplified experience.

So they're kind of seeking something unusual. I think we should just be honest about that

because a lot of times they're not trying to make their brain better. They're just trying to

experience something really amazing. But the problem is space and time are so unlocked

in these states, just like they are in dreams, that you can really end up with a whole lot of

nothing. You can have an amazing amplified experience housed in an amplified experience

and come out of that thinking you had a meaningful experience when you didn't bring anything back.

You didn't bring anything back. All you have is a fuzzy memory of having a transformational

experience. But you don't actually have tools to bring back or actually concrete ideas to bring

back. Yeah, it's interesting. I wonder if it's possible to do that with the mind to be able to

hop back and forth. I think that's where the real power of adjusting states is going to be.

It probably will be with devices. I mean, maybe it'll be done through pharmacology. It's just that

it's hard to do on off switches in human pharmacology, that we have them for animals.

I mean, we have Cree flip recombinases and we have channelopsins and haloridopsins and

all these kinds of things. But to do that work in humans is tricky. But I think you could do it

with virtual reality, augmented reality, and other devices that bring more of the somatic

experience into it. You're, of course, a scientist who's studying humans as a collective. I tend to

be just a one person scientist of just looking at myself. When these deep thinking, deep work

sessions, I'm very cognizant in the morning that there's times when my mind is so

eloquent at being able to jump around for ideas and hold them all together. I'm almost like,

I step back from a third person perspective and enjoy that whatever that mind is doing. I do not

waste those moments. I'm very conscious of this little creature that woke up that's only awake

for, if we're being honest, maybe a couple hours a day. Early part of the day for you. Early part

of the day. Not always. Early part of the day for me is a very fluid concept. You're one of those.

Yeah, you're one of those. Being single, one of the problems. Single and no meetings. I don't

schedule any meetings. I've been living on like a 28 hour day. So I like, it drifts. So it's all

over the place. But after a traditionally defined full night's sleep, whatever the heck that means,

I find that like in those moments, there's a clarity of mind that's just,

everything is effortless. And it's the deepest dives intellectually that I make. And I'm cognizant

of it. And I try to bring that to the other parts of the day that don't have it and treasure them

even more in those moments, because they only last like five or 10 minutes. Because of course,

in those moments, you want to do all kinds of stupid stuff that are completely is worthless,

like Czech social media or something like that. But those are the most precious things in intellectual

life is those mental moments of clarity. And I wonder, I'm learning how to control them.

I think caffeine is somehow involved. I'm not sure exactly.

Sure. Well, because if you learn how to titrate caffeine,

everyone's slightly different with this, what they need. But if you learn to titrate caffeine with

time of day and the kind of work that you're trying to do, you can bring that autonomic

arousal state into the close to perfect place. And then you can tune it in with,

you know, sometimes people want a little bit of background music, sometimes they want less,

these kinds of things. The early part of the day is interesting because the one thing that's not

often discussed is this transition out of sleep. So there's a book, I think it's called Winston

Churchill's nap. And it's about naps and the transition between wake and sleep as a valuable

period. I've a long time ago, someone who I respect a lot was mentoring me said,

be very careful about bringing in someone else's sensory experience early in the day.

So when I wake up, I'm very drowsy. I sleep well, but I don't emerge from that very quickly. I need

a lot of caffeine to wake up and whatnot. But there's this concept of getting the download from

sleep, which is, you know, in sleep, you were essentially expunging the things that you don't

need, the stuff that was meaningless from the previous day. But you were also running variations

on these algorithms of whatever it is you're trying to work out in life on short timescales,

like the previous day and long timescales, like your whole life. And those lateral connections

in layer five of the neocortex are very robustly active and cross sensory areas. And you're running

an algorithm or a brain, it's a brain state that will be useless in waking. You wouldn't get anything

done. You'd be the person talking to yourself in the hallway or something about something that

no one else can see. But in those states, you do that the theory is that you arrive at certain

solutions. And those solutions will reveal themselves in the early part of the day, unless

you interfere with them by bringing in social media is a good example of you immediately enter

somebody else's space time sensory relationship, someone is the conductor of your thoughts in

that case. And so many people have written about this, what I'm saying isn't entirely new, but

allowing the download to occur in the early part of the day. And asking the question,

am I more in my head or am I in more of an interoceptive or exteroceptive mode? And

depending on the kind of work you need to do, if it sounds like for you, it's very interoceptive

and very got a lot of thinking going on and a lot of computing going on, allowing yourself to

transition out of that sleep state and arrive with those solutions from sleep and plug into the work

really deeply. And then and only then allowing things like music, news, social media doesn't

mean you shouldn't talk to loved ones and see faces and things like that. But some people have

taken this to the extreme. When I was a graduate student at Berkeley, there was a guy there

was a professor is brilliant, odd, but brilliant, who was so fixated on this concept that he wouldn't

look at faces in the early part of the day, because he just didn't want to anything else to

impact him. Now he would didn't have the most rounded life, I suppose. But if you're talking

about cognitive performance, this could actually be very beneficial. You said so many brilliant

things. So one, if you read books that describe the habits of brilliant people like writers,

they do control that sensory experience in the in the hours after wake, like many writers,

you know, they have a particular habit of several hours early in the morning of actual

writing, they do don't do anything else for the rest of the day. But they control, they're very

sensitive to noises and so on. I think they make it very difficult to live with them. I try to,

I'm definitely like that, like I could, I, I love to control the sensory, how much information

is coming in. There's something about the peaceful, just everything being peaceful.

At the same time, and we were talking to a mutual friend of Whitney Cummings, who

has has a has a mansion, a castle on top of a cliff in the middle of nowhere, she actually

purchased her own island. She wants silence. She wants to control how much sound is coming in.

She's very sensitive to sound and environment. Yeah. Beautiful home and environment, but like

clearly puts a lot of attention into, into details. Yeah. And very creative. Yeah. And that's,

yeah, that allows for creativity to flourish. I'm also, I don't like, that feels like a slippery

slope. So I enjoy introducing noises and signals and training my mind to be able to tune them out.

Because I feel like you can't always control the environment so perfectly because,

because your mind gets comfortable with that. I think it's a skill that you want to learn to be

able to shut it off. Like I often go to like back before COVID to a coffee shop. It really

annoys me when there's sounds and voices and so on. But I feel like I can train my mind to block

them out. So it's a balance, I think. Yeah. And I think, you know, two things come to mind as

you're saying this. First of all, yeah, I mean, we're talking about what's best for work is not

always what's best for, you know, completeness of life. I mean, you know, autism is probably many

things. Like when you hit autism, just like feet, they're probably 50 ways to get a fever,

they're probably 50 ways to that the brain can create what looks like autism or what people

call autism. There's an interesting set of studies that have come out of David Ginty's lab at Harvard

Med looking at these are mouse mutants where these are models for autism where nothing is

disrupted in the brain proper and in the central nervous system. But the sensory app, the sensory

neurons, the ones that innervate the skin and the ears and everything are are hypersensitive.

And this maps to a mutation in certain forms of human autism. So this means that the overload of

sensory information and sensory experience that a lot of autistics feel, they're like that they

can't tolerate things. And then they get the stereotype behaviors, the rocking and the kind

of the shouting, it, you know, we always thought of that as a brain problem. In some cases, it might

be. But in many cases, it's because they just can't, they seem to have a, it's like turning the

volume up on every sense. And so they're overwhelmed. And none of us want to become like that. I think

it's very hard for them and it's hard for their parents and so forth. So I like the coffee shop

example because the way I think about trying to build up resilience, you know, physically or

mentally or otherwise is one of, I guess we could call it limb, I like to call it limbic friction,

that's not a real scientific term. And I acknowledge that I'm making it up now, because I think it

captures the concept, which is that, you know, we always hear about resilience, it makes it sound

like, oh, you know, under stress, where everything's coming at you, you're gonna stay calm. But there's

another, you know, so limbic, the limbic system wants to pull you in some direction, typically

in the direction of reflexive behavior. And the prefrontal cortex through top down mechanisms

has to suppress that and say, no, we're not going to respond to the banging of the coffee cups behind

me or I'm going to keep focusing. That's pure top down control. So limbic friction is high

in that environment, you've put yourself into a high limbic friction environment mean that the

prefrontal cortex has to work really hard. But there's another side to limbic friction too,

which is when you're very sleepy, there's nothing incoming, it can be completely silent.

And it's hard to engage and focus because you're drifting off and you're getting sleepy. So their

limbic friction is high, but for the opposite reason autonomic arousal is too low. So they're

turning on Netflix in the background or looping a song might boost your level of alertness that

will allow top down control to be in the play exactly the sweet spot you want it. So this is

why earlier I was saying it's all about how we feel inside relative to what's going on on the

outside. We're constantly in this, I guess one way you could envision it spatially, especially if

people are listening to this just an audio is I like to think about it kind of like a glass barbell

where one sphere of perception and attention can be on what's going on with me and one sphere of

attention can be on what's going on with you or something else in the room or in my environment.

But this barbell isn't rigid, it's not really glass. Would plasma work here? I don't know

anything about plasma. Sorry, I don't know. Okay. So imagine that this thing can contort the size

of the globes at the end of this barbell can get bigger or smaller. So let's say I close my eyes

and I bring all my experience into what's going on through interoception internally.

Now it's as if I've got two orbs of perception just on my internal state, but I can also do the

opposite and bring to both orbs of perception outside me. I'm not thinking about my heart rate

or my breathing, I'm just thinking about something I see. And what you'll start to realize as you

kind of use this spatial model is that two things, one is that it's very dynamic and that the more

relaxed we are, the more these two orbs of attention, the two ends of the barbell can move

around freely. The more alert we are, the more rigid they're going to be tethered in place.

And that was designed so that if I have a threat in my environment, it's tethered to that threat.

I'm not going to be, if something's coming to attack me, I'm not going to be like, oh,

my breathing cadence is a little bit quick. That's not how it works. Why? Because both orbs

are linked to that threat. And so my behavior is now actually being driven by something external,

even though I think it's internal. And so I don't want to get too abstract here because I'm a

neuroscientist, I'm not a theorist. But when you start thinking about models of how the brain

work, I mean, brain works, excuse me, they're only really three things that neurons do. They're

either sensory neurons, they're motor neurons, or they're modulating things. And the models of

attention and perception that we have now, 2020, tell us that we've got interoception and extra

reception. They're strongly modulated by levels of autonomic arousal. And that if we want to form

the optimal relationship to some task or some pressure or something, whether or not it's sleep

and impending threat or coding, we need to adjust our internal space time relationship with the

external space time relationship. And I realize I'm repeating what I said earlier. But we can

actually assign circuitry to this stuff. It mostly has to do with how much limbic friction there is,

how much you're being pulled to some source. That source could be internal. If I have pain,

physical pain in my body, I'm going to be much more interoceptive than I am exteroceptive.

You could be talking to me and I'm just going to be thinking about that pain. It's very hard.

And the other thing that we can link it to is top down control, meaning anything in our environment

that has a lot of salience will tend to bring us into more extra reception than interoception.

And again, I don't want to litter the conversation with just a bunch of terms. But

what I think it can be useful for people is to do what essentially you've done, Lex, is to start

developing an awareness. When I wake up, am I mostly in a mode of interoception or extra

reception? When I work well, what does working well look like from the perspective of autonomic

arousal? How alert or calm am I? What kind of balance between internal focus and external

focus is there? And to sort of watch this process throughout the day.

Can you just briefly use this term a lot and be nice to try to get a little more color to it,

which is interoception and extra reception? What are we exactly talking about? What's included

in each category and how much overlap is there? Interoception would be an awareness of anything

that's within the confines or on the surface of my skin that I'm sensing.

So literally physiological. Physiologically, like within the boundaries of my skin

and probably touch to the skin as well. Extra reception would be perception of anything that's

beyond the reach of my skin. So that bottle of water, a scent, a sound, although, and this

can change dramatically, actually, if you have headphones in, you tend to hear things in your

head as opposed to a speaker in the room. That's interesting, yeah.

This is actually the basis of ventriloquism. So there are beautiful experiments done by Greg

Reckon's own up at UC Davis looking at how auditory and visual cues are matched in an array

of speakers. And this will become obvious as I say it, but obviously the ventriloquist doesn't

throw their voice. What they do is they direct your vision to a particular location and you

think the sound is coming from that location. And there are beautiful experiments that Greg

and his colleagues have done where they suddenly introduce an auditory visual mismatch,

and it freaks people out because you can actually make it seem from a perception standpoint as if

the sound arrived from the corner of the room and hit you physically and people will recoil.

And so sounds aren't getting thrown across the room. They're still coming from this

defined location and array of speakers. But this is the way the brain creates these internal

representations. And again, not to, I don't want to go down a rabbit hole, but I think

as much as, I'm sure the listeners appreciate this, but everything in the brain is an abstraction.

I mean, the sensory apparatus that are the eyes and ears and nose and skin and taste and all that

are taking information and with interoception, taking information from sensors inside the body,

the enteric nervous system for the gut. I've got sensory neurons that innervate my liver,

etc., taking all that. And the brain is abstracting that in the same way that if I took a picture

of your face and I handed it to you and I'd say, that's you, you'd say, yeah, that's me.

But if I were an abstract artist, I'd be doing a little bit more of what the brain does,

where if I took a pen and pad and paper, maybe I could do this because I'm a terrible artist,

and I could just mix it up. And let's say I would make your eyes like water bottles,

but I'd flip them upside down and I'd start assigning fruits and objects to the different

features of your face. And I show it to you, I say, Lex, that's you. Say, well, that's not me.

And I'd say, no, but that's my abstraction of you. But that's what the brain does.

The space time relationship of the neurons that fire that encode your face has have no resemblance

to your face. Right. And I think people don't really, I don't know if people have fully internalized

that. But the day that I, and I'm not sure I fully internalized that, because it's weird to think

about, but all neurons can do is fire in space and in time, different neurons in different

sequences, perhaps with different intensities. It's not clear the action potential is all or none,

although neuroscientists don't like to talk about that, even though it's been published in nature

a couple of times. The action potential for a given neuron doesn't always have the exact same

waveform. People, it's in all the textbooks, but you can modify that waveform.

I mean, there's a lot of fascinating stuff with neuroscience about the fuzziness of all the,

of the transfer of information from neuron to neuron. I mean, we certainly touch upon it

every time we at all try to think about the difference between artificial neural networks and

biological neural networks. But can we maybe linger a little bit on this, on the circuitry

that you're getting at. So the brain is just a bunch of stuff firing and it forms abstractions

that are fascinating and beautiful, like layers upon layers upon layers of abstraction.

And I think it just like when you're programming, you know, on programming in Python,

it's awe inspiring to think that underneath it all, it ends up being zeros and ones.

And the computer doesn't know about no stupid Python or Windows or Linux. It only knows about

the zeros and ones in the same way with the brain. Is there something interesting to you

or fundamental to you about the circuitry of the brain that allows for the magic

that's in our mind to emerge? How much do we understand? I mean, maybe even focusing on the

vision system. Is there something specific about the structure of the vision system,

the circuitry of it that allows for the complexity of the vision system to emerge?

Or is it all just a complete chaotic mess that we don't understand?

It's definitely not all a chaotic mess that we don't understand if we're talking about vision.

And that's not just because I'm a vision scientist.

Let's stick to vision.

Let's stick to vision. Well, because in the beauty of the visual system,

the reason David Hubel and Tornton Weasel on the Nobel Prize was because they were

brilliant and forward thinking and adventurous and all that good stuff.

But the reason that the visual system is such a great model for addressing these kinds of

questions and other systems are hard is we can control the stimuli. We can adjust spatial frequency,

how finer the gratings are, thick gratings, thin gratings, we can adjust temporal frequency,

how fast things are moving. We can use coenisolating stimuli.

We can use it. There's so many things that you can do in a controlled way,

whereas if we're talking about cognitive encoding, encoding the space of concepts or

something, I like you, if I may, am drawn to the big questions in neuroscience.

But I confess, in part because of some good advice I got early in my career,

and in part because I'm not perhaps smart enough to go after the really high level stuff,

I also like to address things that are tractable. And we need to address what we can stand to make

some ground on at a given time. You can construct brilliant controlled experiments

to study, to really literally answer questions about it, yeah.

Yeah, I mean, I'm happy to have a talk about consciousness, but it's a scary talk, and I

think most people don't want to hear what I have to say, which is we can save that for later,

perhaps, or another day. I mean, it's an interesting question of

we talk about psychedelics, we can talk about consciousness, we can talk about cognition.

Can experiments in neuroscience be constructed to shed any kind of light on these questions?

So I mean, it's cool that vision, I mean, to me, vision is probably one of the most beautiful

things about human beings. Also, from the AI side, computer vision has some of the most

exciting applications of neural networks is in computer vision. But it feels like that's a

neighbor of cognition and consciousness. It's just that we maybe haven't come up with experiments

to study those yet. Yeah, the visual system is amazing. We're mostly visual animals to navigate

it, survive humans mainly rely on vision, not smell or something else. But it's a filter for

cognition, and it's a strong driver of cognition, maybe just because it came up and then we're

moving to higher level concepts. The way the visual system works can be summarized in a few

relatively succinct statements, unlike most of what I've said, which has not been succinct at all.

Let's go there. The retina. Yeah, so the retina is this three layers of neuron structure at the

back of your eyes, but I think it's a credit card. It is a piece of your brain. And sometimes people

think I'm kind of wriggling out of reality by saying that it's absolutely a piece of the brain.

It's a four brain structure that in the first trimester, there's a genetic program

that made sure that that neural retina, which is part of your central nervous system,

was squeezed out into what's called the embryonic eye cups, and that the bone formed with a little

hole where the optic nerve is going to connect it to the rest of the brain. And that window

into the world is the only window into the world for a mammal, which has a thick skull.

Birds have a thin skull, so their pineal gland sits and lizards too, and snakes actually have

a hole so that light can make it down into the pineal directly and in trained melatonin rhythms

for time of day and time of year. Humans have to do all that through the eyes.

So, three layers of neurons that are a piece of your brain, their central nervous system,

and the optic nerve connects to the rest of the brain. The neurons in the eye,

some just care about luminance, just how bright or dim it is, and they inform the brain about

time of day, and then the central circadian clock informs every cell in your body about time of

day and make sure that all sorts of good stuff happens if you're getting light in your eyes

at the right times, and all sorts of bad things happen if you are getting light randomly throughout

the 24 hour cycle. We could talk about all that, but this is a good incentive for keeping

a relatively normal schedule, consistent schedule of light exposure. Consistent schedule,

try and keep a consistent schedule. When you're young, it's easy to go off schedule and recover.

As you get older, it gets harder, but you see everything from outcomes in cancer patients to

diabetes improves when people are getting light at a particular time of day and getting darkness

at a particular phase of the 24 hour cycle. We were designed to get light and dark at different

times of the circadian cycle. All that information is coming in through specialized type of neuron

in the retina called the melanopsin intrinsically photosensitive ganglion cell discovered by

David Berson at Brown University. That's not spatial information. It's subconscious. You

don't think, oh, it's daytime. Even if you're looking at the sun, it doesn't matter. It's a

photon counter. It's literally counting photons. It's saying, oh, even though it's a cloudy day,

lots of photons coming in at winter in Boston, it must be winter, and your system is a little

depressed. It's spring, you feel alert. That's not a coincidence. That's these melanopsin cells

signaling the circadian clock. There are a bunch of other neurons in the eye that signal to the

brain, and they mainly signal the presence of things that are lighter than background or darker

than background. A black object would be darker than background, a light object lighter than

background. It's looking at pixels. Mainly, they look at circles, and those neurons have

receptive fields, which not everyone will understand, but those neurons respond best to

little circles of dark light or little circles of bright light. Little circles of red light versus

little circles of green light or blue light. It sounds very basic. It's like red, green, blue,

and circles brighter or dimmer than what's next to it. That's basically the only information that

sent down the optic nerve. When we say information, we can be very precise. I don't mean little bits

of red traveling down the optic nerve. I mean spikes, neural action potentials in space and time,

which for you makes total sense, but I think for a lot of people, it's actually beautiful to think

about all that information in the outside world is converted into a language that's very simple.

It's just a few syllables, if you will. Those syllables are being shouted down the optic

nerve converted into a totally different language like Morse code. Beep, beep, beep, beep, beep.

Goes into the brain, and then the thalamus essentially responds in the same way that the

retina does, except the thalamus is also weighting things. It's saying, you know what,

that thing was moving faster than everything else, or it's brighter than everything else,

so that signal I'm going to allow up to cortex. Or that signal is much redder than it is green,

so I'm going to let that signal go through that signal as much. It's kind of more like the red

next to it. Throw that out. The information just doesn't get up into your cortex. And then in cortex,

of course, is where perceptions happen. And in V1, if you will, visual area one,

but also some neighboring areas, you start getting representations of things like oriented lines. So

there's a neuron that responds to this angle of my hand versus vertical. This is the defining work

of Hubel and Wiesel's Nobel. And it's a very systematic map of orientation, line orientation,

direction of movement, and so forth. And that's pretty much end color. And that's how the visual

system is organized all the way up to the cortex. So it's hierarchical. You don't build, I want to

be clear, it's hierarchical because you don't build up that line by suddenly having a neuron that

responds to lines in some random way. It responds to lines by taking all the dots that are aligned

in a vertical stack, and they all converge on one neuron. And then that neuron responds to vertical

lines. So it's not random. There's no abstraction at that point, in fact. In fact, if I showed you

a black line, I could be sure that if I were imaging V1, that I would see a representation

of that black line as a vertical line somewhere in your cortex. So at that point, it's absolutely

concrete. It's not abstract. But then things get really mysterious. Some of that information travels

further up into the cortex and goes from one visual area to the next, to the next, to the next,

so that by time you get into an area that Nancy Kenwisher at MIT has studied much of her career,

the fusiform face area, you start finding single neurons that respond only to your father's face

or to Joe Rogan's face, regardless of the orientation of his face. I'm sure if you saw Joe,

because you know him well, from across the room and you just saw his profile, you'd be like,

oh, that's Joe. Walk over and say hello. The orientation of his face isn't there. You wouldn't

even see his eyes necessarily. But he's represented in some abstract way by a neuron that actually

would be called the Joe Rogan neuron or collection neurons. You might have limits. I might not

recognize him if he was upside down or something like that. It'd be fascinating to see what the

limits of that Joe Rogan concept is. So Nancy's lab has done that because early on,

she was challenged by people that said there aren't face neurons. There are neurons that

they only respond to space and time, shapes and things like that, moving in particular

directions and orientations. And it turns out Nancy was right. They used these stimuli

called greeble stimuli, which any computer programmer would appreciate, which kind of morphs

a face into something gradually that eventually just looks like this alien thing they call the

greeble. And the neurons don't respond to greebles. In most cases, they only respond to faces and

familiar faces. Anyway, I'm summarizing a lot of literature and forgive me, Nancy, and for those

of the greeble people, if there are anything like, don't come after me with pitchforks. Actually,

you know what? Come after me with pitchforks. I think you know what I'm trying to do here.

So the point is that in the visual system, it's very concrete up until about visual area four,

which has color pinwheels and seems to respond to pinwheels of colors. And so the stimuli become

more and more elaborate. But at some point, you depart that concrete representation and you start

getting abstract representations that can't be explained by simple point to point wiring.

And to take a leap out of the visual system to the higher level concepts,

what we talked about in the visual system, maps to the auditory system where you're encoding what

that frequency of tone sweeps. So this is going to sound weird to do, but like a Doppler,

like hearing something, car passing by, for instance. But at some point, you get into motifs

of music that can't be mapped to just what they call a tonotopic map of frequency. You start

abstracting. And if you start thinking about concepts of creativity and love and memory,

like what is the map of memory space? Well, your memories are very different than mine,

but presumably there's enough structure at the early stages of memory processing,

or at the early stages of emotional processing, or at the earlier stages of creative processing

that you have the building blocks, your zeros and ones, if you will,

but you depart from that eventually. Now, the exception to this, and I want to be really clear

because I was just mainly talking about neocortex, the six layered structure on the outside of the

brain that explains a lot of human abilities, other animals have them too, is that subcortical

structures are a lot more like machines. It's more plung and chug. And what I'm talking about

is the machinery that controls heart rate and breathing and receptive fields, neurons that

respond to things like temperature on the top of my left hand. And I came into neuroscience from

the more of a perspective initially of psychology, but one of the reasons I forced upon myself to

learn some electrophysiology, not a ton, but enough. And some molecular biology and about

circuitry is that one of the most beautiful experiences you can have in life, I'm convinced,

is to lower an electrode into the cortex and to show a person or an animal,

you do this ethically, of course, stimulus, like an oriented line or a face. And you can

convert the recordings coming off of that electrode into an audio signal, an audio monitor,

and you can hear what they call hash. It's not the hash you smoke, it's the hash you hear,

and it sounds like noise. And in the cortex, eventually you find a stimulus that gets the

neuron to spike in fire action potentials that convert it into an auditory stimulus

that are very concrete. Crack, crack, crack sounds like a bat cracking, like home runs

or outfield balls. When you drop electrodes deeper into the thalamus or into the hypothalamus

or into the brainstem areas that control breathing, it's like a machine. You never hear

hash. You drop the electrode down. This could be like a grungy old Tuggestin electrode,

not high fidelity electrode, as long as it's got a little bit of insulation on it. You plug

it into an audio monitor, it's picking up electricity. And if it's a visual neuron and

it's in the thalamus or the retina and you walk in front of that animal or person, that neuron goes

crack, and then you walk away and it stops. And you put your hand in front of the eye again and

it goes crack, and you could do that for two days. And that neuron will just, every time

there's a stimulus, it fires. So whereas before, it's a question of how much information is getting

up to cortex. And then these abstractions happening where you're creating these ideas,

when you go subcortical, everything is... There's no abstractions. It's two plus two equals four.

There's no abstractions. And this is why I know we have some common friends at Neural Link.

And I love the demonstration they did recently. I'm a huge fan of what they're doing and where

they're headed. And no, I don't get paid to say that. And I have no business relationship to them.

I'm just a huge fan of the people in the mission. But my question was to some of them,

when are you going to go subcortical? Because if you want to control an animal,

you don't do it in the cortex. The cortex is like the abstract painting I made of your face.

Removing one piece or changing something may or may not matter for the abstraction. But when

you are in the subcortical areas of the brain, a stimulating electro can evoke an entire behavior

or an entire state. And so the brain, if we're going to have a discussion about the brain and how

the brain works, we need to really be clear which brain. Because everyone loves neocortex.

It's like, oh, canonical circuits in cortex, we can get the cortical connectome. And sure,

necessary, but not sufficient. Not to be able to plug in patterns of electrical stimulation

and get behavior. Eventually we'll get there. But if you're talking subcortical circuits,

that's where the action is. That's where you could potentially cure Parkinson's by stimulating

the subthalamic nucleus. Because we know that it gates motor activation patterns in very predictable

ways. So I think for those that are interested in neuroscience, it pays to pay attention to,

like, is this a circuit that abstracts the sensory information? Or is it just one that builds up

hierarchical models in a very predictable way? And there's a huge chasm in neuroscience right

now because there's no conceptual leadership. No one knows which way to go. And this is why I think

Neuralink has captured an amazing opportunity, which was, okay, well, while all you academic

research labs are figuring all this stuff out, we're going to pick a very specific goal and make

the goal the endpoint. And some academic laboratories do that. But I think that's a beautiful way to

attack this whole thing about the brain because it's very concrete. Let's restore motion to the

Parkinsonian patient. Academic labs want to do that too, of course. Let's restore

speech to the stroke patient. But there's nothing abstract about that. That's about

figuring out the solution to a particular problem. So anyway, those are my, and I admit I've mixed

in a lot of opinion there. But having spent some time, like 25 years digging around in the brain

and listening to neurons firing and looking at them anatomically, I think, given it's 2020,

we need to ask the right, you know, the way to get better answers, ask better questions. And

the really high level stuff is fun. It makes for good conversation. And it has brought enormous

interest. But I think the questions about consciousness and dreaming and stuff, they're

fascinating. But I don't know that we're there yet.

So you're saying there might be a chasm in the two views

of the power of the brain arising from the circuitry that forms abstractions or the power of

the brain arising from the majority of the circuitry that's just doing very brute force

dumb things that don't have any fancy kind of stuff going on. That's really interesting to think

about. And which one to go after first? And here I'm poaching badly from someone I've never met,

but whose work I follow, which is, and it was actually on your podcast, I think Elon Musk

said, you know, basically the brain is a monkey brain with a supercomputer on top.

And I thought that's actually probably the best description of the brain I've ever heard,

because it captures a lot of important features like limbic friction, right? But we think of like,

oh, you know, when we're making plans, we're using the prefrontal cortex and we're

executive function and all this kind of stuff. But think about the drug addict,

who's driven to go pursue heroin or cocaine, they make plans. So clearly they use their

frontal cortex, it's just that it's been hijacked by the limbic system and all the monkey brain

as you refer to. It's really not fair to monkeys though, Elon, because actually monkeys can make

plans. They just don't make plans as sophisticated as us. I've spent a lot of time with monkeys,

but I've also spent a lot of time with humans. Anyway, I'm you're putting you're saying like,

which there's a lot of value to focusing on the monkey brain or whatever the heck you call it.

I do because let's say I had an ability to place a chip anywhere I wanted in the brain today,

and activate it or inhibit that area. I'm not sure I would put that chip in neocortex,

except maybe to just kind of have some fun and see what happens. The reason is it's an

abstraction machine. And especially if I wanted to make a mass production tool, a tool in mass

production that I could give to a lot of people, because it's quite possible that your abstractions

are different enough than mine, that I wouldn't know what patterns of firing to induce. But if I

want, let's say I want to increase my level of focus and creativity, well, then I would love to

be able to, for instance, control my level of limbic friction. I would love to be able to wake up

and go, oh, you know, I have an eight o clock appointment, I wake up slowly. So between seven,

eight, but I want to do a lot of linear thinking. So you know what, I'm going to just, I'm going to

turn down the limbic friction and or ramp up prefrontal cortex is activation. So there's a

lot of stuff that can happen in the thalamus with sensory gating. For instance, you could shut down

that shell around the thalamus and allow more creative thinking by allowing more lateral

connections. These would be some of the those would be the experiments I'd want to do. So

they're in the subcortical, quote unquote, monkey brain. But you could then look at what

sorts of abstract thoughts and behaviors would arise from that, rather than and here I'm not

pointing my finger at neural link at all. But there's this obsession with neocortex. But I'm

going to, well, I might lose a few friends, but I'll hopefully gain a few. And also,

one of the reasons people spend so much time in neocortex is I have a fact and an opinion. One

fact is that you can image there and you can record there. Right now, the two photon and one

photon microscopy methods that allow you to image deep into the brain still don't allow you to image

down really deep unless you're jamming prisms in there and endoscopes. And then the endoscopes

are very narrow. So you're getting very, you know, it's like looking at the bottom of the ocean

through a through a spotlight. And so you much easier look at the waves up on top, right? So

let's face it, folks, a lot of the reasons why there's so many recordings in layer two, three of

cortex with all this advanced microscopy is because it's very hard to image deeper. Now,

the microscopes are getting better. And thanks to the amazing work mainly of engineers and

chemists and physicists, let's face it, they're the ones who brought this revolution to neuroscience

in the last 10 years or so, you can image deeper. But we don't really, that's why you see so many

reports on layer two, three. The other thing, which is purely opinion, and I'm not going after

anybody here, but is that as long as there's no clear right answer, it becomes a little easier

to do creative work in a structure where no one really knows how it works. So it's fun to probe

around because anything you see is novel. If you're going to work in the thalamus or the pulvinar or

the hypothalamus or these structures they've been known about since the 60s and 70s and really

since the centuries ago, you are dealing with exist, you have to combat existing models.

Yeah. And we're as in cortex, no one knows how the thing works. Neocortex, six layer cortex.

And so there's a lot more room for discovery. There's a lot more room for discovery. And I'm

not calling anyone out. I love cortex. We've published some papers on cortex. It's super

interesting. But I think with the tools that are available nowadays, and where people are trying

to head of not just reading from the brain, monitoring activity, but writing to the brain,

I think we really have to be careful and we need to be thoughtful about what are we trying to write?

What script are we trying to write? Because there are many brain structures for which we

already know what scripts they write. And I think there's tremendous value there. I don't think it's

boring. The fact that they act like machines makes them predictable. Those are your zeros and ones.

Let's start there. But what's sort of happening in this field of writing to the brain is there's

this idea. And again, I want to be clear, I'm not pointing at neural link. I'm mainly pointing at

the neocortical jockeys out there that you go in, you observe patterns, and then you think replaying

those patterns is going to give rise to something interesting. I should call out one experiment

or two experiments which were done by Sasumoto Nagawa, Nobel Prize winner from MIT, done important

work in memory and immunology, of course, as well as Mark Mayford's lab at UC San Diego.

They did an experiment where they monitored a bunch of neurons while an animal learned something.

Then they captured those neurons through some molecular tricks so they could replay the neurons.

So now there's like perfect case scenario. It's like, okay, you monitor the neurons in your brain,

then I say, okay, neurons one through 100 were played in the particular sequence. So you know

the space time, you know the keys on the piano that were played that gave rise to the song,

which was the behavior. And then you go back and you reactivate those neurons, except you

reactivate them all at once, like slamming on all the keys once on the piano. And you get the exact

same behavior. So the space time code may be meaningless for some structures. Now that's

freaky. That's a scary thing because what that means is that all the space time firing in cortex,

the space part may matter more than the time part. So you know, rate codes and space time codes,

we don't know. And you know, I'd rather have more, I'd rather deliver more answers in this

discussion questions. But I think it's an important consideration. You're saying some of the magic

is in the early stages of what the closer to the raw information. I believe so. I believe so. You

know the stimulus, you know, the neuron then codes that stimulus, so you know the transformation.

When I say this for those that will think about sensory transformations, it's like,

I can show you a red circle. And then I look at how many times the neuron fires in response to

that red circle. And then I could show the red circle a bunch of times, green circle,

see if it changes. And then essentially the number of times that is the transformation,

you've converted red circle into like three action potentials, you know,

or whatever you want to call it, you know, for those that think in sound space. So

that's what you've created, you know, the transformation and you march up the, it's

called the nerve axis as you go from the periphery up into the cortex. And we know that,

and I know Lisa Feldman Barrett, or is it Barrett Feldman? Barrett Feldman, excuse me,

Lisa, that talked a lot about this, that, you know, birds can do sophisticated things and

whatnot as well. But humans, there's a strong what we call sephalization. A lot of the processing

is moved up into the cortex and out of these subcortical areas. But it happens nonetheless.

And so as long as you know the transformations, you are in a perfect place to build machines

or add machines to the brain that exactly mimic what the brain wants to do, which is take events

in the environment and turn them into internal firing of neurons. So the mastery of the brain

can happen at their early load. You know, another perspective of it is you saying this means that

humans aren't that special. If we look at the evolutionary time scale, the leap to intelligence

is not that special. So like the extra layers of abstraction isn't where most of the magic

happens of intelligence, which gives me hope that maybe if that's true, that means the evolution

of intelligence is not that rare of an event. I certainly hope not. I hope there are other

forms of intelligence. I mean, I think what humans are really good at, and here I want to

be clear that this is not a formal model, but what humans are really good at is taking that

plasma barbell that we were talking about earlier and not just using it for analysis of space,

like the your media environment, but also using historical information. Like I can read a book

today about the history of medicine. I happen to be doing that lately for some stuff I'm researching.

And I can take that information. And if I want, I can inject it into my plans for the future.

Other animals don't seem to do that over the same time scales that we do. Now, it may be that the

chipmunks are all hiding little notebooks everywhere in the form of little dirt castles or

something that we don't understand. I mean, the waggle dance of the bee is in the most famous

example. Bees come back to the hive, they orient relative to the honeycomb, and they waggle.

There's a guy down in Australia named Serena Vissan who studied this in it. It's really

interesting. No one really understands it except he understands it best. The bee waggles in a couple

ways relative to the orientation of the honeycomb. And then all the other bees see that it's visual

and they go out and they know the exact coordinate system to get to the source of whatever was the

food and bring it back. And he's done it where they isolate the bees, he's changed the visual

flight environment, all this stuff. They are communicating. And they're communicating something

about something they saw recently, but it doesn't extend over very long periods of time.

The same way that you and I can both read a book or you can recommend something to me and then we

could converge on a set of ideas later. And in fairness, because she was the one that said it

and I didn't and I hadn't even thought of it, when you talked to Lisa on your podcast, she

brought up something beautiful, which is that I never really occurred to me and I was sort of

embarrassed that it hadn't. But it's really beautiful and brilliant, which is that we don't

just encode senses in the form of color and light and sound waves and taste, but ideas become a form

of sensory mapping. And that's where the really, really cool and exciting stuff is, but we just

don't understand what the receptive fields are for ideas. What's an idea of receptive field?

And how they're communicated between humans because we seem to be able to encode those ideas

in some kind of way. Yes, it's taking all the raw information and the internal physical states,

the that sensory information put into this concept blob that we store and then we're

able to communicate that. Your abstractions are different than mine. I actually think the

comment section on social media is a beautiful example of where the abstractions

are different for different people. So much of the misunderstanding of the world

is because of these idea receptive fields. They're not the same. Whereas I can look at

a photoreceptor neuron or olfactory neuron or a V1 neuron. And I am certain I would bet my life

that yours look and respond exactly the same way that Lisa's do and mine do. But once you get

beyond there, it gets tricky. And so when you say something or I say something and somebody gets upset

about it or even happy about it, their concept of that might be quite a bit different. They don't

really know what you mean. They only know what it means to them. Yeah, so from a neural link

perspective, it makes sense to optimize the control and the augmentation of the of the more

primitive circuitry. So like the stuff that is closer to the raw sensory information.

Go deeper if they I think by the way deeper into the brain. And to be fair, so Matt McDougall,

who's the neurosurgeon neural link and clinical nurse, a great guy, brilliant. They have amazing

people. I have to give it to them. They have been very cryptic in recent years. Their website was

just like a neural like nothing there. They really know how to do things with style and

they've upset a lot of people, but that's good too. But Matt is there. I know Matt,

he actually came out through my lab at Stanford, although he was a neurosurgery resident. We

spent time in our lab. He actually came out on the shark dive and did great white shark diving

with my lab to collect the VR that we use in our fear stuff. I've talked to Matt and I think he

and other folks that are hungry for the deeper brain structures. The problem is that damn vasculature,

all that blood supply. It's not trivial to get through and down into the brain without damaging

the vasculature in the neocortex, which is on the outer crust. But once you start getting into

the thalamus and closer to some of the main arterial sources, you really risk getting

massive bleeds. It's an issue that can be worked out. It just is hard.

Maybe it'd be nice to educate. I'm sure of my ignorance. The smart stuff is on the surface.

I didn't quite realize because you keep saying deep. The early stages are deep

in actual physically in the brain. Of course, you've got your deep brain structures that

are involved in breathing and heart rate and kind of lizard brain stuff. And then on top of that,

this is the model of the brain that no one really subscribes to anymore. But anatomically,

it works. And then on top in mammals. And then on top of that, you have the limbic structures,

which gate sensory information and decide whether or not you're going to listen to

something more that you're going to look at it or you're going to split your attention to both.

Kind of sensory allocation stuff. And then the neocortex is on the outside. And that is where

you get a lot of this abstraction stuff. And now not all cortical areas are doing abstraction,

some are like visual area one, auditory area one, they're just doing concrete representations.

But as you get into the higher order stuff, that when you start hearing names like

infro, parietal cortex, and when you start hearing multiple names in the same,

then you're talking about higher order areas. But actually, there's an important experiment

that drives a lot of what people want to do with brain machine interface. And that's the work of

Bill Newsom, who is at Stanford and Tony Moveshin, who runs the Center for Neural Science at NYU.

This is a wild experiment. And I think it might freak a few people out if they really think about

it too deeply. But anyway, here he goes. There's an area called MT in the cortex. And if I showed

you a bunch of dots all moving up, and this is what Tony and Bill and some of the other people

in that lab did way back when, is they show a bunch of dots moving up. Somewhere in MT,

there are some neurons that respond, they fire when the neurons move up. And then what they did

is they started varying the coherence of that motion. So they made it so only 50% of the dots

moved up and the rest move randomly. And that neuron fires a little less. And eventually,

it's random and that neuron stops firing because it's just kind of dots moving everywhere.

It's awesome. And there's a systematic map so that other neurons are responding and

things moving down and other things are responding left and other things are moving right. Okay.

So there's a map of direction space. Okay, well, that's great. You could lesion MT,

animals lose the ability to do these kind of coherence discrimination or direction

discrimination. But the amazing experiment, the one that just is kind of eerie, is that

they lowered a stimulating electrode into MT, found a neuron that responds to when dots go up. But

then they silenced that neuron. And sure enough, the animal doesn't recognize the neurons are going

up. And then they move the dots down. They stimulate the neuron that responds to things

moving up. And the animal responds, because it can't speak, it responds by doing a lever

press, which says the dots are moving up. So in other words, the sensory, the dots are moving

down in reality on the computer screen. They're stimulating the neuron that responds to dots

moving up. And the perception of the animal is that dots are moving up, which tells you that

your perception of external reality absolutely has to be a neuronal abstraction. It is not

tacked to the movement of the dots in any absolute way. Your perception of the outside world depends

entirely on the activation patterns of neurons in the brain. And you can hear that and say, well,

duh, because if I stimulate the stretch reflex and you kick or something or whatever,

the knee reflex, and you kick, of course, there's a neuron that triggers that,

but it didn't have to be that way. Because A, the animal had prior experience. B,

you're way up in this higher order cortical areas. What this means is that, and I generally try to

avoid conversations about this kind of thing, but what this means is that we are constructing our

reality with this space time firing the zeros and ones. And it doesn't have to have anything to do

with the actual reality. And the animal or person can be absolutely convinced that that's what's

happening. Are you familiar with the work of Donald Hoffman? So he's, so he makes an evolution

argument. That's not important. That we, our brains are completely detached from reality,

in the sense that he makes a radical case that we have no idea what physical reality is. And in fact,

is drastically different than what we think it is. Oh my. So he goes, that's scary. So he doesn't

say like there's just, because you're kind of implying there's a, there's a gap. There might,

there might be a gap. We're constructing an illusion. And then maybe using communication to

maybe create a consistency that's sufficient for human collaboration, whatever, or mammal could,

you know, just maybe even just life forms are constructing a consistent reality that's maybe

detached. I mean, that's really cool that neurons are constructing that, like that you can prove

this is when you were science at his best vision science. But he says that like, our brain is actually

just lost its shit on the path of evolution to where we're normal. We're just playing games

with each other in constructing realities that allow our survival. But it's completely detached

from physical reality. We're missing a lot. We're missing like most of it, if not all of it.

Well, this was, it's fascinating because I just saw the Oliver Sacks documentary,

there's a new documentary out about his life. And there's this one part where he's like,

I've spent part of my life trying to imagine what it would like to be to be a bat or something to

see the world through the life, the sensory apparatus of a bat. And he did this with these

patients that were locked into these horrible syndromes that to pull out some of the beauty of

their experience as well, not just communicate the suffering, although the suffering too.

And as I was listening to him talk about this, I started to realize, it's like,

well, what, you know, like they're these mantis shrimps that can see 60 shades of

pink or something. And they see this stuff all the time and animals, they can see UV light.

Every time I learn about an animal that can sense other things in the environment that I

can't like heat sensing, why not? I don't crave that experience the same way Sacks talked about

craving that experience. But it does throw another penny in the jar for what you're saying, which is

that it could be that most, if not all of what I perceive and believe is just a neural fabrication.

And that for better or for worse, we all agree on enough of the same neural

fabrications in the same time and place that we're able to function.

Not only that, but we agree with the things that are trying to eat us

enough to where we don't, they don't eat us, meaning like that it's not just us humans,

you know, I see, because it's interactive, it's interactive. So like, so like, now,

I think it's a really nice thought experiment. I think because Donald really frames it in a

scientific, like he makes a hard, like as hard as our discussion has been now, he makes a hard

scientific case that we don't know shit about reality. I think that's a little bit hard core,

but I think it's, I think it's our core. But I think it's a good thought experiment

that kind of cleanses the palate of the confidence we might have about about because we are operating

in the subtraction space. And, you know, and, you know, the sensory spaces might be something very

different. And it's kind of interesting to think about if you start to go into a realm of neural

link or start to talk about just everything that you've been talking about with dream states and

psychedelics and stuff like that, which part of the which layer can we control and play around with

to maybe look into a different slice of reality? You just got to do the experiment. The key is to

just do the experiment in the most ethical way possible. You just, I mean, that's the beauty

of experiments. This is why, you know, there's, there's wonderful theoretical neuroscience happening

now to make predictions. But that's why experimental science is so wonderful. You can go into the

laboratory and poke around in there and be a brain explorer and listen to and write to neurons.

And when you do that, you get answers. You don't always get the answers you want, but that's,

you know, that's the beauty of it. I think when you were saying this thing about reality and the

Donald Hoffman model, I was thinking about children, you know, like when I have an older

sister, she's very sane. But when she was a kid, she had an imaginary friend. And she played with

this imaginary friend. And it had, there was this whole, there was a consistency. This friend was

like, it was Larry lived in a purple house. Larry was a girl. It was like all this stuff that a

child, a young child wouldn't have any issue with. And then one day she announced that Larry had

died, right? And it wasn't traumatic or traumatic. And that was it. And she just stopped. And I

always wonder what that neurodevelopmental event was that a kept her out of a psychiatric ward

had she got, you know, kept that imaginary friend. But it's also there was something kind of sad to

it. I think the way it was told to me because I'm the younger brother, I didn't, I wasn't around

for that. But my dad told me that, you know, there was a kind of a sadness because it was this

beautiful reality that had been constructed. And so we kind of wonder, I wonder as you're

telling me this, whether or not, you know, as adults, we try and create as much reality for

children as we can so that they can make predictions and feel safe because the ability to make

predictions is a lot of what keeps our autonomic arousal in check. I mean, we go to sleep every

night and we give up total control. And that should frighten us deeply. But, you know,

unfortunately, autonomic arousal be yanks us down under and we don't negotiate too much.

So you sleep sooner or later. I don't know. I was a little worried we get into discussions

about the nature of reality because it's interesting. In the laboratory, I'm very much

like, what's the experiment? What's the analysis going to look like? What mutant mouse are we going

to use? What experience are we going to put someone through? But I think it's wonderful

that in 2020, we can finally have discussions about this stuff and look kind of peek around

the corner and say, well, no link. And people, others who are doing similar things,

are going to figure it out. The answers will show up and we just have to be open to interpretation.

Do you think there could be an experiment centered around consciousness? I mean, you're

plugged into the neuroscience community. I think for the longest time, the quote unquote,

C word was totally not, was almost anti scientific. But now more and more people are talking about

consciousness. Elon is talking about consciousness. AI folks are talking about consciousness.

It's still nobody knows anything, but it feels like a legitimate domain of inquiry that's hungry

for a real experiment. So I have, fortunately, three short answers to this.

The first one is a, I'm not, I'm not particularly succinct. I agree. The joke I always tell is

there are two things you never want to say to a scientist. One is what do you do? And the second

one is take as much time as you need. And you definitely don't want to say them in the same

sentence. I have three short answers to it. So there's a, there's a cynical answer kind of,

and it's not one I enjoy giving, which is that if you look into the 70s and a back at the 1970s

and 1980s, and even into the early 2000s, there were some very dynamic, very impressive speakers

who are very smart in the field of neuroscience and related fields who thought hard about the

consciousness problem and fell in love with the problem, but overlooked the fact that the

technology wasn't there. So I admire them for falling in love with the problem, but they gleaned

tremendous taxpayer resources, essentially for nothing. And these people know who they are,

some of them are alive, some of them aren't. I'm not referring to Francis Crick, who was brilliant,

by the way, and thought the classroom was involved in consciousness, which I think is a

great idea. It's this obscure structure that no one's really studied. People are now starting

to study it. So I think Francis was brilliant and wonderful. But there it, you know, there were

books written about it. It makes for great television stuff and thought around the table

or after a couple glasses of wine or whatever. It's an important problem nonetheless. And so I

think I do think the consciousness, the issue is it's not operationally defined, right? That

psychologists are much smarter than a lot of hard scientists in that for the following reason,

and they put operational definitions. They know that psychology, if we're talking about motivation,

for instance, they know they need to put operational definitions on that so that

two laboratories can know they're studying the same thing. The problem with consciousness is

no one can agree on what that is. And this was a problem for attention when I was coming up. So

in the early 2000s, people would argue, what is attention? Is it spatial attention, auditory

attention? And finally, people are like, you know what, we agree. Have they agreed on that one?

I remember hearing people scream a lot of attention. Right. They couldn't even agree on

attention. So I was coming up as a young graduate student, I'm thinking like,

I'm definitely not going to work on attention. And I'm definitely not going to work on consciousness.

And I wanted something that I could solve or figure out. I want to be able to see the circuit

or the neurons. I want to be able to hear it on the audio. I want to record from it. And then I

want to do gain a function and loss a function, take it away, see something change, put it back,

see something change a systematic way. And that takes you down into the depths of some stuff

that's pretty plug and chug. But I'll borrow from something in the military because I'm

fortunate to do some work with units from special operations and they have beautiful language

around things because their world is not abstract. And they talk about three meter targets,

10 meter targets and 100 meter targets. And it's not an issue of picking the 100 meter target

because it's more beautiful or because it's more interesting. If you don't take down the

three meter targets and the 10 meter targets first, you're dead. So I think scientists could pay to

adopt a more kind of military thinking in that sense. The other thing that is really

important is that just because somebody conceived of something and can talk about it beautifully

and can glean a lot of resources for it, doesn't mean that it's led anywhere. So this isn't just

true of the consciousness issue. And I don't want to sound cynical, but I could pull up some names

of molecules that occupied hundreds of articles in the very premier journals that then were later

discovered to be totally moot for that process. And biotech companies folded everyone and the

lab pivots and starts doing something different with that molecule. And nobody talks about it

because as long as you're in the game, we have this thing called anonymous peer review. You

can't afford to piss off anybody too much unless you have some other funding stream. And I have

avoided battles most of my career, but I pay attention to all of it. And I've watched this

and I don't think it's ego driven. I think it's that people fall in love with an idea. I don't

think there's any, there's not enough money in science for people to sit back there rubbing

their hands together. The beauty of what Neuralink and Elon and team, because obviously he's

very impressive, but the team as a whole is really what gives me great confidence in their mission,

is that he's already got enough money, so it can't be about that. He doesn't seem to need it at a

level of, I don't know him, but he doesn't seem to need it at a kind of an ego level or something.

I think it's driven by genuine curiosity. And the team that he's assembled include people that

are very kind of abstract neuro neocortex, space time coding people. They're people like Matt,

who is a neurosurgeon. You can't BS neurosurgery. Failures in neurosurgery are not tolerated,

so you have to be very good to exceptional to even get through the gate. And he's exceptional.

And then they've got people like Dan Adams, who was at UCSF for a long time, is a good

friend and a known name for years, who is very concrete, studied the vasculature in the eye

and how it maps to the vasculature in cortex. When you get a team like that together,

you're going to have dissenters. You're going to have people that are high level thinkers,

people that are coders. When you get a team like that, it no longer looks like an academic

laboratory or even a field in science. And so I think they're going to solve some really hard

problems. And again, I'm not here, I have nothing at stake with them. But I think that's the solution.

You need a bunch of people who don't need first author papers, who don't need to complete their

PhD, who aren't relying on outside funding, who have a clear mission, and you have a bunch of

people who are basically will adapt to solve the problem. I like the analogy of the three

meter target and the hundred meter target. So the folks at Neuralink are basically many of them

are some of the best people in the world at the three meter target. Like you mentioned Matt,

Neurosurgery, like they're solving real problems. There's no BS, philosophical

smoke. So we need to look back and look at the stars. But

so both on Elon and because I think like this, I think it's really important to think about

the hundred meter and the hundred meter is not even not even a hundred meter, but like

like the stuff behind the hill that's that's that's too far too far away, which is which is

where I put consciousness. I'm maybe I tend to believe that consciousness can be engineered.

I mean, part of the reason part of the the the business I want to build leverages that idea

that consciousness is a lot simpler that we've then we've been talking about.

Well, if someone can simplify the problem, right, that will be wonderful. I mean, the reason we can

talk about something as abstract as face representations and fusiform face area is

because Nancy Kenwisher had the brilliance to tie it to the kind of lower level statistics

of visual scenes. It wasn't because she was like, oh, I bet it's there. That wouldn't have been

interesting. So people like her understand how to bridge that gap. And they put a tractable definition.

So I just that's what I'm begging for in science is a tractable definition.

This is what but I want people to sit in it. I want people who are really uncomfortable with

woo woo, like consciousness, like high level stuff to sit in that topic and sit uncomfortably,

because it forces them to then try to ground and simplify it into something that's concrete.

Because too many people are just uncomfortable to sit in the consciousness room,

because there's no definitions. It's like attention or intelligence in the artificial

intelligence community. But the reality is, it's easy to avoid that room all together,

which is what I mean, there's analogies to everything you've said with the artificial

intelligence community with Minsky and even Alan Turing that talked about intelligence a lot.

And then they drew a lot of funding and then it crashed because they really didn't do anything

with it. And it was a lot of force of personality and so on. But that doesn't mean the topic of

the Turing test and intelligence isn't something we should sit on and think. Turing actually

attempted this with the Turing test. He tried to make concrete this very question of intelligence.

It doesn't mean that we shouldn't linger on it. And we shouldn't forget that ultimately that is

what our efforts are all about in the artificial intelligence community. And in the people,

whether it's neuroscience or whatever bigger umbrella you want to use for understanding the

mind, the goal is not just about understanding layer two or three of the vision. It's to understand

consciousness and intelligence and maybe create it or just all the possible biggest questions

of our universe. That's ultimately the dream. Absolutely. And I think what I really appreciate

about what you're saying is that everybody, whether or not they're working on a kind of

low level synapse that's like a reflex in the musculature or something very high level abstract

can benefit from looking at those who prefer three, everyone's going after three meter,

10 meter and 100 meter targets in some sense. But to be able to tolerate the discomfort of

being in a conversation where there are real answers where the zeros and ones are known zeros

and ones are those the equivalent of them in the nervous system. And also, as you said,

for the people that are very much like, oh, I can only trust what I can see and touch,

those people need to put themselves into the discomfort of the high level conversation because

what's missing is conversation and conceptualization of things at multiple levels. I think one of the

this is I don't gripe about my life's been fortunate, we've been funded from the start and

we've been happy in that regard and lucky and we're grateful for that. But I think one of the

challenges of research being so expensive is that there isn't a lot of time, especially nowadays,

for people to just convene around a topic because there's so much emphasis on productivity. And

so there are actually, believe it or not, there aren't that many concepts, formal concepts in

neuroscience right now. The last 10 years has been this huge influx of tools. And so people

in neural circuits and probing around and connectomes, it's been wonderful. But 10,

20 years ago, when the consciousness stuff was more prominent, the C word, as you said,

what was good about that time is that people would go to meetings and actually discuss ideas and

models. Now, it's sort of like demonstration day at the School of Science Fair where everyone's

got their thing and some stuff is cooler than others. But I think we're going to see a shift.

I'm grateful that we have so many computer scientists and theoreticians and or theorists,

I think they call themselves. Somebody tell me what the difference is someday. And psychology and

even dare I say philosophy, these things are starting to converge. Neuroscience,

the name neuroscience, there wasn't even such a thing. When I started graduate school or as a

postdoc, it was neurophysiology or you're a neuroanatomist or what now, it's sort of everybody's

invited. And that's beautiful. That means that something useful is going to come up all this.

And there's also tremendous work, of course, happening for the treatment of disease. And

we shouldn't overlook that. That's where eliminating, reducing suffering is also a huge

initiative of neuroscience. So there's a lot of beauty in the field. But the consciousness thing

continues to be a, it's like an exotic bird. It's like, no one really quite knows how to handle it

and it dies very easily. Well, yeah, I think also from the AI perspective, I so I view the brain

as less sacred. I think from a neuroscience perspective, you're a little bit more sensitive

to BS, like BS narratives about the brain or whatever. I'm a little bit more comfortable

with just poetic BS about the brain as long as it helps engineer intelligence systems.

Well, I mean,

and I have to, you know, I confess ignorance when it comes to, you know, most things about coding

and I have some quantitative ability, but I don't have strong quantitative leanings. And so

I know my limitations too. And so I think the next generation coming up, you know, a lot of the

students at Stanford are really interested in quantitative models and theory and AI. And

I remember when I was coming up, a lot of the people who were doing work ahead of me, I kind of

rolled my eyes at some of the stuff they were doing, including some of their personalities,

although I have many great senior colleagues everywhere, the world. So it's the way of the

world. So nobody knows what it's like to be, you know, a young graduate student in 2020 except

the young graduate students. So I know what I do. I know there are a lot of things I don't know.

And in addition to why I do a lot of public education, increased scientific literacy and

neuroscientific thinking, etc. A big goal of mine is to try and at least pave the way so that

these really brilliant and forward thinking younger scientists can make the biggest possible

dent and make what will eventually be all us old guys and gals look stupid. I mean, that's

what we were all trying to do. That's what we were trying to do. So yeah. So from the highest

possible topic of consciousness to the, to the lowest level topic of David Goggins, let's go.

I don't know if it's low level. He's high performance. High performance. But like low,

like there's no, I don't think David has, has, has any time for philosophy. Let's just put it

this way. Well, it's, I mean, I think we can tack it to what we were just saying in a, in a

meaningful way, which is whatever goes on in that abstraction part of the brain, he's figured,

you know, he's figured out how to dig down in whatever the limbic friction. He's figured out

how to grab ahold of that, scruff it and send it in the direction that he's decided it needs to go.

And what's wild is that he's what we're talking about is him doing that to himself. Right? He's,

it's like he's scruffing himself and directing himself in a particular direction

and sending himself down that trajectory. And he, what's beautiful is that he acknowledges

that that process is not pretty. It doesn't feel good. It's kind of horrible at every level.

But he's created this rewarding element to it. And I think that's what's so, it's so admirable.

And it's what so many people crave, which is regulation of the self at that level.

And he practices, I mean, there's a ritual to it. There's every single day, like no exceptions.

There's a practice aspect to the suffering that he goes through.

It's principle suffering. Principle suffering. I mean, I just, I mean,

I admire all aspects of it, including him and his girlfriend slash wife. I'm not sure.

Should probably know this. I don't know. I'm not asking him.

No, no, we've only communicated, I've only communicated with her by text about some stuff

I was asking David. But yeah, they clearly have formed a powerful team.

Yeah. And it's a beautiful thing to see people working in that kind of synergy.

It's inspiring to me, same as with Elon, that a guy like David Goggins can find love.

That you find a thing that works, which gives me hope that like whatever,

whatever flavor of crazy I am, you can always find another thing that works with that.

But I've had the, so maybe let's trade Goggins stories, you're from a neuroscience

perspective, me from a self inflicted pain perspective. I somehow found myself

in communication with David about some challenges that I was undergoing.

One of which is we were communicating every single day, email phone about the particular

30 day challenge that I did and that stretched for longer of pushups and pullups.

You made a call out on social media. Yeah, social media.

Actually, I think that was the point. I knew of you before, but that's where I started tracking

some of what you were doing with these physical challenges. And I,

the hell is wrong with that guy? Well, no, I think I actually, I don't often comment on people's

stuff, but I think I commented something like neuroplasticity loves a non negotiable rule.

But no, I said a non negotiable contract because at the point where yeah, neuroplasticity really

loves a non negotiable contract because, you know, and I've said this before, so forgive me,

but you know, the brain is doing analysis of duration path and outcome. And that's a lot

of work for the brain. And the more that it can pass off duration path and outcome to just

reflex, the more energy and it can allocate to other things. So if you decide there's no

negotiation about how many pushups, how far I'm going to run, how many days, how many pullups,

et cetera, you actually have more energy for pushups running in pullups.

And when you say neuroplasticity, you mean like the brain wants the decision is made,

it'll start rewiring stuff to, to make sure that this we can actually make this happen.

That's right. I mean, so much of what we do is reflexive at the level of just core circuitry,

breathing, heart rate, all that boring stuff, digestion. But then there's a lot of reflexive

stuff like how you drink out of a mug of coffee, that's reflexive too, but that you had to learn

at some point in your life earlier when you were very little, analyzing duration path and outcome.

And that involves a lot of top down processing with the prefrontal cortex. But through plasticity

mechanisms, you now do it. So when you take on a challenge, provided that you understand the core

mechanics of how to, you know, run pushups and pullups and whatever else you decided to do.

Once you set the number and the duration and all that, then you all you have to do is just go.

But people get caught in that tide pool of just, well, do I really have to do it? How do I not do

that? What if I get injured? What if I, you know, can I sneak at this? So that, you know, and that's

work. And to some extent, I look, I not David Goggins, obviously, nor nor do I claim to understand

his process. Partially, you know, but maybe a little bit, which is that it's clear that by

making the decision, there's more resources to devote to the effort of the actual execution.

Well, that's a really, like what you're saying was not a lesson that was obvious to me. And it's

still not obvious. It's something I really work at, which is there is always an option to quit.

And I mean, that's something I really struggle with. I mean, I've quit some things in my life.

It's like stupid stuff. And one lesson I've learned is if you quit once, it opens the door

that like, it's really valuable to trick your brain into thinking

that you're going to have to die before you quit. Like, it's actually really convenient. So actually,

what you're saying is very profound, but you shouldn't intellectualize it. Like,

it took me time to develop, like out psychologically in ways that I think it would be

another conversation, because I'm not sure how to put it into words, but it's really tough

on me to do certain parts of that challenge.

Well, it's a huge output.

I thought it would be the number would be hard, but it's not. It's the entirety of it,

especially in the early days, was just spending, I'm kind of embarrassed to say how many hours

this took. So I didn't say publicly how many hours because people I knew people would be like,

don't you aren't you supposed to do other stuff? Well, it's how are you doing?

Again, I don't want to speculate too much about but occasionally, David has said this publicly

where people will be like, don't you sleep or something? And his process used to just be that

he would just block, delete, you know, like gone. But it's actually, it's a super interesting

topic. And because self control and directing our actions and the role of emotion and quitting,

these are vital to the human experience. And they're vital to performing well at anything.

And obviously at a super high level, being able to understand this about the self is crucial.

So I have a friend who was also in the teams. His name is Pat Dossett. He did nine years in the

SEAL teams. And in a similar way, there's a lore about him among team guys, because of a kind of

funny challenge he gave himself, which was so he and I swim together, although he swims further

up front than I do. And he's very patient. But, you know, he was on a he was assigned when he

was in the teams to a position that gave him a little more time behind a desk than he wanted.

And there's not as much time out in deployments, although he did deployments. So he didn't know

what to do at that time. But he thought about it and he asked himself, what does he hate the most?

And it turns out the thing that he hated doing the most was bear crawls, you know,

walking in your hands and knees. So he decided to bear crawl for a mile for time. So he was

bear crawling a mile a day, right? And I thought that was an interesting example that he gave,

because, you know, like, why pick the thing you hate the most? And I think it maps right back

to limbic friction. It's the thing that creates the most limbic friction. And so if you can overcome

that, then there's carryover. And I think the notion of carryover has been talked about psychologically

and kind of in the self help space, like, oh, if you run a marathon, it's going to help you in

other areas of life. But will it really? Will it? Well, I think it depends on whether or not

there's a lot of limbic friction. Because if there is, what you're exercising is not a circuit

for bear crawls, or a circuit for pull ups, what you're doing is you're exercising a circuit for

top down control. And that circuit was not designed to be for bear crawls, or pull ups, or coding,

or waking up in the middle of the night to do something hard. That circuit was designed to

override limbic friction. And so neural circuits were designed to generalize, right? The stress

response to an incoming threat that's a physical threat was designed to feel the same way and be

the same response internally as the threat to an impending exam, or divorce, or marriage, or whatever

it is that's stressing somebody out. And so neural circuits are not designed to be for one particular

action or purpose. So if you can, as you did, if you can train up top down control under conditions

of the highest limbic friction, that when the desired acquit is at its utmost, either because

of fatigue or hyperarousal, being too stressed or too tired, you're learning how to engage a

circuit. And that circuit is forever with you. And if you don't engage it, it sits there, but

it's atrophied. It's like a plant that doesn't get any water. And a lot of this has been discussed

in self help and growth mindset and all these kinds of ideas that circle the internet and social

media. But when you start to think about how they map to neural circuits, I think there's some

utility because what it means is that the limbic friction that you'll experience in, I don't know,

maybe some future relationship to something or someone, it's a category of neural processing

that should immediately click into place. It's just like the limbic friction you experienced

trying to engage in the God knows how many push ups, pull ups, and running runs you were doing.

25,000, 20,000. So folks, if Lex does this again, more comments, more likes.

This is the problem with you getting more followers as you're going to get more.

Actually, I should say that's the benefit. I don't know. Maybe it's not politically

correct for me to ask, but there is this stereotype about Russians being like being really

durable. And I started going to that Russian Banya way back before COVID and they could tolerate a

lot of heat and they would sit very stoic and no one was going, oh, it's hot in here. They were

just kind of like ease into it. So maybe there's something there who knows.

There might be something there, but it could be also just personal. I just have some,

I found myself, everyone's different, but I've found myself to be able to do

something unpleasant for very long periods of time. Like, I'm able to shut off the mind.

And I don't think that's been fully tested.

Monkey mind or the supercomputer?

Well, it's interesting. I mean, which mind tells you to quit exactly?

Limbic friction tells you.

Limbic friction is the source of that, but who are you talking with exactly?

So there's a, we can put something very concrete to that. So there's a paper published in Cell,

super top tier journal, two years ago, looking at effort. And this was in a visual environment

of trying to swim forward toward a target and a reward. And it was a really cool experiment

because they manipulated virtually the visual environment. So the same amount of effort was

being expended every time, but sometimes the perception was you're making forward progress

and sometimes the perception was you're making no progress because stuff wasn't drifting by,

meant no progress. So you can be swimming and swimming and not making progress.

And it turns out that with each bout of effort, there's a epinephrine and norepinephrine is being

released in the brainstem. And glia, what traditionally were thought of as support cells

for the neurons, but they do a lot of things actively too, are measuring the amount of

epinephrine and norepinephrine in that circuit. And when it exceeds a certain threshold,

the glia send inhibitory signals that shut down, top down control, they literally,

it's the quit, you stop, there's no more, it's you quit enduring. It can be rescued,

endurance can be rescued with dopamine. So that's where the subjective part really comes into play.

So you quit because you've learned how to turn that off or you've learned how to,

some people will reward the pain process so much that friction becomes the reward.

And when you talk about people like Goggins and other people I know from special operations and

people have gone through cancer treatments three times, you hear about, just when you hear about

people, the Victor Frankel stories, I mean, you hear about Nelson Mandela, you hear about these

stories, I'm sure the same process is involved. Again, this speaks to the generalizability of

these processes as opposed to a neural circuit for a particular action or cognitive function.

So I think you have to learn to subjectively self reward in a way that replenishes you.

Goggins talks about eating souls. It's a very dramatic example. In his mind, apparently,

that's a form of reward, but it's not just a form of reward where it's like you're picking up a

trophy or something. It's actually it gives the energy. It's a reward that gives more neural energy

and I'm defining that as more dopamine to suppress the noradrenaline and adrenaline circuits in the

brainstem. So ultimately maps of that. Yeah, he creates enemies. He's always fighting enemies.

I never, I think I have enemies, but they're usually just versions of me inside my head.

So I thought about through that 30 day challenge, I tried to come up with like

fake enemies. It wasn't working. The only enemy I came up with is David.

Well, now you certainly have a formidable adversary in this one. I don't care. David,

I'm willing to die on this one. So let's go there. Well, let's hope you both survive this.

Well, my problem is the physical. So everything we've been talking about has been in the mind.

There's a physical aspect that's just practically difficult, which is when you injure yourself

at a certain point, you just can't function. Or you're doing more damage talking about it,

taking yourself out of running for the rest of your life potentially or for years. So

you know, I'd love to avoid that, right? There's just like stupid physical stuff that you just

want to avoid. You want to keep it purely in the mental. And if it's purely in the mental,

that's when the race is interesting. But yeah, the problem with these physical challenges,

as David has experienced, I mean, it has a toll on your body. I tend to think of the mind as

limitless and the body is kind of unfortunately quite limited. Well, I think the key is to

dynamically control your output. And that can be done by reducing effort, which doesn't work throughout,

but also by restoring through these subjective reward processes. And we don't want to go down

the rabbit hole of why this all works. But these are ancient pathways that were designed to

bring resources to an animal or to a person through foraging for hunting or mates or water or

all these things. And they work so well because they're down in those circuits where we know

the zeros and ones. And that's great because it can be subjective at the level of, oh, I reached

this one milestone, this one horizon, this one three meter target. But if you don't reward it,

it's just effort. If you do self reward it, it's effort minus one in terms of the adrenaline output.

But I have to ask you about this. You're one of the great communicators in science. I'm

really a big fan of yours enjoying in terms of like the educational stuff you're putting

on neuroscience. Thank you. What's the, do you have a philosophy behind it or is it just an

instinct? Oh my unstoppable force. Do you have like, what's your thinking? Because it's rare

and it's exciting. I'm excited that somebody from Stanford, so I, okay, I'm in multiple places in

the sense of like where my interests lie. And politically speaking, academic institutions

are under fire for many reasons we don't need to get into. I get into it in a lot of other places.

But I believe in places like Stanford and places like MIT as one of the most magical

institutions for inspiring people to dream, people to build the future. I mean, I believe

that it is a really special, these universities are really special places. And so it's always

exciting to me when somebody as inspiring as you represents those places. So it makes me

proud that somebody from Stanford is like something like you is representing Stanford.

So maybe you could speak to what's, how did you come to be who you are in being a communicator?

Well, first of all, thanks for the kind words, especially coming from you. I think

Stanford is an amazing place as is MIT. And it's such a... MIT is better by the way.

I'll let it out anything you say at this point. I've got many friends at MIT.

Smarter friends, yeah. Ed Boyden is among the best in class. There's some people,

not me, that can hold a candle to him, but not many, maybe one or two. I think the

great benefit of being in a place like MIT or Stanford is that when you look around,

the average is very high. You have many best in class among the one or two or three best in

the world at what they do. And it's a wonderful privilege to be there. And one thing that I

think also makes them and other universities like them very special is that there's an emphasis on

what gets exported out of the university, not keeping it ivory tower and really trying to keep

an eye on what's needed in the world and trying to do something useful. And I think the proximity

to industry and Silicon Valley and in the Boston area in Cambridge also lends itself well to that.

And there are other institutions too, of course. So the reason I got involved in educating on

social media was actually because of Pat Dossett, the mile bear call guy. I was at the turn of

2018 to 2019. We had formed a good friendship and he talked to me into doing these early morning

cold water swims. I was learning a lot about pain and suffering, but also the beauty of cold water

swims. And we were talking one morning, he said, so what are you going to do to serve the world

in 2019? That's the way that a Texan former seal talks. We're just literally like, what are you

going to do to serve the world in 2019? Well, I run my lab, it's like, no, no, no, what are you

going to do that's new? And he wasn't forceful in it, but I was like, that's interesting question.

I said, well, if I had my way, I would just teach people, everyone about the brain because I think

it's amazing. He goes, we'll do it. All right. He goes, shake on it. So we did it. And so I

started putting out these posts and it's grown into to include a variety of things. But you asked

about a governing philosophy. So I want to increase interest in the brain and in the nervous system

and in biology generally. That's one major goal. I'd like to increase scientific literacy, which

can't be rammed down people's throats of talking about how to look at a graph and statistics and

z scores and p values and genetics. It has to be done gradually in my opinion. I want to put

valuable tools into the world, mainly tools that map to things that we're doing in our lab.

So these will be tools centered around how to understand and direct one's states of mind and

body. So reduce stress, raise one's stress threshold. So it's not always just about being

calm. Sometimes it's about learning how to tolerate not being not calm,

raise awareness for mental health. There's a ton of micro missions in this. But it all really maps

back to the eight and 10 year old version of me, which is I used to spend my weekends when I was

a kid reading about weird animals. And I had this obsession with medieval weapons and stuff like

catapults. And then I used to come into school on Monday and I would ask if I could talk about it

to the class and teach. And I promise and some people might not believe me, but I don't really

like being the point of focus. I just get so excited about these gems that I find in the

world in books and in experiments and in discussions with colleagues and discussions with people like

you and around the universe. And just compulsively, I got to tell people about it. So I try and package

it into a form that people can access. I think the reception has been really wonderful. Stanford

has been very supportive, thankfully. I've done some podcasts even with them and they've reposted

some stuff on social media. It's a precarious place to put yourself out there as a research

academic. I think some of my colleagues, both locally and elsewhere, probably wonder if I'm

still serious about research, which I absolutely am. And I also acknowledge that their research and

the research coming out of the field needs to be talked about. And not all scientists are good at

translating that into a language that people can access. And I don't like the phrase dumb it down.

What I like to do is take a concept that I think people will find interesting and useful

and offer it sort of like you would offer food to somebody visiting your home. You're not going

to cram Fragras in their face. You're going to say, do you want a cracker? And they say, yeah,

do you want something on that cracker? Do you like cheese? Yeah, do you want Swiss cheese or

you want that really stinky French cheese? I don't like cheese much. But do you want

Fragras? What's that? So the best information prompts more questions of interest, not questions

of confusion, but questions of interest. And so I feel like one door opens, then another door opens,

then another door opens. And pretty soon, the image in my mind is you create a bunch of neuroscientists

who are thinking about themselves neuroscientifically. And I don't begin to think that I have all the

answers at all. I cast a neuroscience, sometimes a little bit of a psychology lens onto what I

think are interesting topics. And someday I'm going to go into the ground or the ocean or

wherever it is I end up. And I'm very comfortable with the fact that not everyone's going to be

happy with how I deliver the information. But I would hope that people would feel like some of

it was useful and meaningful and got them to think a little bit harder. Since you mentioned going

into the ground and Victor Franco man search for meaning, I reread that book quite often. Let me

ask the the big ridiculous question about life. What do you think is the the meaning of it all?

Like maybe why do you do you mention that book from a psychologist's perspective,

which Victor Franco was? Do you ever think about the the bigger philosophical questions

that raises about meaning? What's and the meaning of it all?

One of the great challenges in assigning a good, you know, giving a good answer to the question

of like, what's the meaning of life is, I think illustrated best by the Victor Franco example,

although there are other examples too, which is that our sense of meaning is very elastic

in time and space. And we talked a little bit about this earlier, but it's amazing to me that

somebody locked in a cell or a concentration camp can bring the horizon in close enough

that they can then micro slice their environment so that they can find rewards and meaning and power

and beauty even in a little square box or or a horrible situation. And I think this is really

speaks to one of the most important features of the human mind, which is we could do let's take two

opposite extremes. One would be, let's say the alarm went off right now in this building and the

building started shaking. Our vision, our hearing, everything would be tuned to this space time bubble

for those moments. And everything that we would process, all that would matter, the only meaning

would be get out of here safe, figure out what's going on, contact loved ones, etc. If we were

to sit back totally relaxed, we could do the, you know, as I think it's called pale blue dot thing

or whatever, where we could imagine ourselves in this room, and then they were in the United

States and this continent and the earth and then it's peering down us. And all of a sudden you

get back, it can seem so big that all of a sudden it's meaningless, right? If you see yourself as

just one brief glimmer in all of time and all of space, you go to, I don't matter. And if you go to,

oh, every little thing that happens in this text thread or this, you know, comment section on

YouTube or Instagram, your space time bubble is tiny, then everything seems inflated and the brain

will contract and dilate its space time, vision and time, but also sense of meaning. And that's

beautiful. And it's what allows us to be so dynamic in different environments and we can pull from

the past and the present and future. It's why examples like Nelson Mandela and Victor Frankel

had to include. It makes sense that it wasn't just about grinding it out, they had to find

those dopamine rewards even in those little boxes they were forced into. So I'm not trying to dodge

an answer, but for me personally, and I think about this a lot, because I have this complicated

history in science where my undergraduate graduate advisor and postdoctoral advisor all died young.

So, you know, and they were wonderful people and had immense importance in my life. But what I

realized is that we can get so fixated on the thing that we're experiencing holding tremendous

meaning, but it only holds that meaning for as long as we're in that space time regime. And this

is important because what really gives meaning is the understanding that you can move between

these different space time dimensionalities. And I'm not trying to sound like a theoretical

physicist or anyone that thinks about the cosmos and saying that. It's really the fact that sometimes

we say and do and think things and it feels so important. And then two days later, we're like,

what happened? Well, you had a different brain processing algorithm entirely, you were in a

completely different state. And so what I want to do in this lifetime is I want to engage in as

many different levels of contraction and dilation of meaning as possible. I want to go to the micro.

I sometimes think about this. I'm like, if I just pulled over the side of the road, I bet you

there's an ant hill there and their whole world is fascinating. You can't stay there. And you also

can't stay staring up at the clouds and just think about how we're just these little beings and it

doesn't matter. The key is the journey back and forth up and down that staircase back and forth

and back and forth. And my goal is to get as many trips up and down that staircase as I can before

the Reaper comes for me. Oh, beautiful. So the dance of dilation and contraction between the

difference, zoom in, zoom out, and get as many steps in on that staircase. That's my goal anyway.

And I've watched people die. I watched my postdoc advisor die with or away. It was tragic, but

they found beauty in these closing moments because their bubble was their kids in one case or

like one of them was a Giants fan and got to see a Giants game in her last moments.

And you just realize it's a Giants game, but not in that moment because time is closing and so

those time bins feel huge because she's slicing things so differently. So I think learning how

to do that better and more fluidly, recognizing where one is and not getting too tacked to the

idea that there's one correct answer, like that's what brings meaning. That's my goal anyway.

I don't think there's a better way to end it. Andrew, I really appreciate that you would come

down and contract your space time and focus on this conversation for a few hours. It is

a huge honor. I'm a huge fan of yours as I told you. I hope you keep growing and educating the world

about the human mind. Thanks for talking today. Thank you. I really appreciate the invitation

to be here. And people might think that I'm saying it just because I'm here, but I'm a huge fan of

yours. I send your podcasts to my colleagues and other people. And I think what you're doing isn't

just amazing. It's important. And so thank you. Thanks for listening to this conversation with

Andrew Huberman. And thank you to our sponsors. ASleep, a mattress that cools itself and gives

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from Carl Jung. I am not what happened to me. I am what I choose to become. Thank you for listening

and hope to see you next time.