Oftentimes people will ask me like an

older person will say, "Hey, I do cross

word puzzles. Is that good?" Yeah, it's

good until you get good at it and then

stop and do something that you're not

good at and constantly find the next

thing that's a real challenge for you.

That's the key thing about plasticity.

Your brain is locked in silence and

darkness. It's trying to make a model of

the outside world. And if you're

constantly pushing and challenging it

with things it doesn't understand, then

it'll keep changing. Welcome to the

Huberman Lab podcast where we discuss

science and science-based tools [music]

for everyday life.

I'm Andrew Huberman and I'm a professor

of neurobiology and opthalmology at

Stanford School of Medicine. My guest

today is Dr. David Eagleman. Dr. David

Eagleman is a neuroscientist, a

best-selling author, and a longtime

science public educator. Today we

discuss several different features of

brain science that impact your everyday

life. And once you understand the

mechanisms behind these features, it

will position you to make better

decisions and if you choose to rewire

your brain to be a more effective

learner. We start by discussing

neuroplasticity, which is your brain's

ability to change in response to

experience or any form of deliberate

learning that you are trying to impose

on yourself. We talk about the

mechanisms for it and how you can get

better at learning and unlearning in the

context of skills and information. We

also discuss memory formation and the

relationship between stress and time

perception and why it is that people

experience things in slow motion if

those things are very stressful or

traumatic and how that can be useful for

undoing traumatic memories. David also

takes us through the neuroscience of

cultural and political polarization,

something that's very timely right now,

false memories, deja vu, dreams and the

meaning of dreams and a lot more. David

is an absolutely legendary science

communicator. I say this as a fellow

neuroscientist. He is able to embed

factual information about the brain into

real life stories and in doing so he's

able to shed light on how we work as

humans and how we can all improve our

life experience. He's a true virtuoso of

neuroscience and science education more

generally. What David shares with us

today will change the way that you think

about thinking and your own mind and no

doubt will also change the way that you

view the world. Before we begin, I'd

like to emphasize that this podcast is

separate from my teaching and research

roles at Stanford. It is however part of

my desire and effort to bring zero cost

to consumer information about science

and science related tools to the general

public. In keeping with that theme,

today's episode does include sponsors.

And now for my discussion with Dr. David

Eagleman. Dr. David Eagleman, welcome.

>> Thanks. Great to see you, Andrew. Man, I

feel like the kid that was a freshman

when you were a senior because you got

into this public facing science

education long before I did. And you've

had a an amazing career also in your

laboratory work. And today I want to

talk about all of it,

>> right? um by mostly listening and you

doing the talking and there are so many

topics in neuroscience that are

fascinating as you know but I think

perhaps the most fascinating thing about

the human brain is its ability to change

itself.

>> Yeah.

>> Plasticity. So I know how I think about

neuroplasticity. I want to know how you

think about neuroplasticity. What it is

and how we should think about it and

what we could possibly do with that

information.

>> Okay, great. I mean, this was mother

nature's big trick with humans was

figuring out how to drop a creature into

the world with a halfbaked brain and

then let the world wire up the rest of

it. And so, you know, 1953, Crick and

Watton, I worked with Crick at the Salt.

They burst into the Eagle and Child pub

and said, "We've discovered the secret

to life." Because they figure out the

structure of DNA. But that was really

half the secret of life because the

other half is all around us. It's every

bit of experience that you have. It's

your culture. It's your language. It's

your neighborhood. All of that stuff

gets absorbed by the brain and wires us

up. And I often think about this issue

of what if you were born 30,000 years

ago exactly your DNA? You pop out and

you look around and the question is

would you be you? The answer is you

wouldn't be. You'd look maybe similar

because of the same genetic blueprint,

but you would have a different culture

and a different language and different

stories and all that stuff. You'd be a

very different kind of person. So, brain

plasticity, for anyone who doesn't know,

it's it's that the brain is constantly

reconfiguring itself every second of

your life. You got 86 billion neurons.

And really, the way to think about it,

these are like little creatures that are

all crawling around and moving around.

each one is, you know, on average

contacting 10,000 of its neighbors, but

it's not like a fixed thing like you

might see in a textbook. Instead,

they're, you know, plugging and

unplugging and searching around and

finding new places to plug in, of

course, changing the strength of those

connections.

And I actually always find this weird.

It's like having all these little

creatures in your head that are

slithering around, but that's what makes

us absorb every single thing in our

worlds. And this is what uh you know

humans have that other creatures have

less of. And that's why we've taken over

every corner of the earth. That's why we

have succeed. We've gotten off the

planet. We build skyscrapers and compos

symphonies and so on because each

generation we land and we get to spend

our first few years absorbing everything

that's been discovered before us. And

then we springboard off of that and do

something new. Because we are able to

figure out all the discoveries

that have come before us because of this

ability to reconfigure our own

circuitry.

>> And uh you know if you were a an

alligator born 30,000 years ago, you'd

be the same alligator. You know, eat,

mate, swim, whatever, and you you

wouldn't be meaningfully different. But

but humans because of our flexibility,

we are the the dominant species.

>> Such an interesting take on time and

human evolution that uh and I completely

agree with you. I just had never thought

about it this way before that we land uh

when we're born and we're absorbing the

um the outcroppings of all the

neuroplasticity that came before us. We

often hear that, you know, that the

human brain is is kind of like a macac

monkey brain with a supercomputer added

on top of it. Mostly the prefrontal

cortex. A bit more prefrontal cortex.

Prefrontal cortex. Prefrontal cortex. We

actually cortex in general.

>> Yeah. Interesting.

>> We we have four times as much cortex as

our nearest neighbors in the animal

kingdom. And that seems to be the

magical stuff.

>> Not just prefrontal cortex,

>> right? And for I'm sure the listenership

knows this, but you know, uh the cortex

is just the outer 3 millimeters of the

brain. It's that wrinkly bit. And that's

the magic stuff because it turns out

cortex is a one-trick pony. The reason

the cortex looks the same everywhere is

because it is the same. It's got the

same circuitry. It's got six little

layers. It's doing the same algorithms

and it gets defined by what you plug

into it. So if you plug in a cable

that's carrying visual information, then

it becomes visual cortex. And we look at

it and we say, "Oh, look, it detects the

orientation of lines. and a detect

motion, things like that. If you plug

auditory information into it, it becomes

auditory cortex and so on. And it turns

out, you know, the way we do this in

textbooks is we make a picture and we

say, "Look, that's visual cortex, that's

auditory, that's the metaensory." But

all this stuff is really flexible. It's

it's so much more interesting than the

textbook model because you can take the

fibers and plug them in somewhere else.

So you may know this study in 2000 by

Morgankaur at MIT where he in a farret

took uh the visual information visual uh

the optic nerve and he plugged it into

the visual sorry into the auditory

cortex and then the what would have been

the auditory cortex became visually

responsive and it started caring about

vision. So what does that mean? It means

the cortex is a onetrick pony and we got

so much more of it including the

prefrontal cortex. So that has two major

effects. One is that there's a lot more

room with our species in between input

and output. So with a a squirrel or a

cat or even a macac monkey, you know,

you throw some food in front of it, it

that that sensory cortex is right next

to the motor cortex, it's going to eat

the thing, but we've got all this

computational real estate in between in

and out. So we can say, well, I'm on a

diet. I'm trying whatever you I'll eat

it later. We've got all these other

options that we can take. That's one

thing. And then the other thing is

exactly what you pointed to, which is

the prefrontal cortex, which allows us

to simulate whatifs. Allows us to think

about possible futures, simulate things

in a way that we don't have to risk our

lives doing it. We can simulate it and

say, "Oh, that would be a bad idea. Oh,

that'd be a pretty good idea." And then

we can take the action.

>> Couple different questions. Um, I'm a

big fan of McGranka's work, and I'm so

glad you mentioned that work. it it

really points to the fact that while

there are cortical areas that are

genetically devoted by virtue of wiring

when we arrive in the world too auditory

or visual that there's a lot of

crossover especially in the extreme

cases so my understanding correct me if

I'm wrong is that um if somebody is

blind from birth the real estate that

would be allocated to vision becomes

allocated to tactile sensation

especially if they learn how to braille

read um maybe auditory processing and

because they rely on it more so there's

really no blank real estate in the

cortex it's all used.

>> That is exactly right. So it turns out

um you know right people who are born

blind what we call the visual cortex at

the back of the back of the head here

that gets taken over. It's no longer

visual. It becomes devoted to hearing to

touch to memory things like this. And

you can demonstrate that people who are

born blind are better at hearing and and

at touch and so on. They can

discriminate things much more finely. Um

same with people who go deaf that the

auditory cortex all that real estate

nothing lies in the brain all that gets

taken over for different tasks and they

can do things like see your accent you

know just by lip reading they can tell

where in the country you're from and so

on. Um all of this demonstrates that

first of all the more real estate you

have the better. We are in a sense if

you've got all your senses you uh you

have to share everything and so we're

pretty good at vision and hearing and

touch and so on but everything has to

get shared. But there are pretty

extraordinary things that happen when

people devote more real estate towards

one task. And by the way, just as a side

note, this is one hypothesis about what

goes on with savantism in in autism is

that somebody for whatever genetic set

of reasons ends up devoting a ton of

real estate to let's say the Rubik's

cube or the piano or memorizing visual

scenes or something and then they are

absolutely superhuman at it. That comes

at the cost of other things. Let's say

social skills that might be needed. Um,

but the general story is if you devote a

lot of real estate towards something,

you're gonna get really good at it.

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I don't know if you saw this study that

was published in science recently that

explored um early specialization in

sport or creative endeavor versus kids

that played a bunch of different sports

or involved in a bunch of different

creative endeavors. And it turns out

that um specializing too early on

average doesn't play out so well in

terms of um kind of uh peak of success

later. Now there are exceptions, right?

But um turns out that being a bit more

diversified in in your uh physical

activities and cognitive activities as a

as a young person into the early teens

even um and beyond uh is more

beneficial. And this this to me kind of

runs counter to my images of like um

Tiger Woods uh putting uh golf balls

with his uh dad when he was, you know,

kind of still waddling. He was so

little, right? and then he becomes Tiger

Woods or um or the Williams sisters who

were you know early on. I think that

especially in the United States we have

this notion that early specialization is

really what sets you up to be

spectacularly good later. So I'm curious

what your general thoughts are for the

the every person. I mean you have kids

um and some of us still are kids who are

listening and and we all have plasticity

into adulthood. you know, is do you

think that we come into the world with

some genetic leanings toward particular

activities being right for us or more

right for us? And how do you think about

it in terms of how many difficult hard

to access things we do just so that

we're sure that we have a full

experience of life? Because what I hear

you saying and I totally subscribe to is

that our early experience becomes the

funnel through which we have more or

less opportunity later. like the kind of

width of the of the funnel depends on

how many things we did or didn't do

early on.

>> So this is really interesting because um

first of all take somebody like the

Williams sisters they got drilled on

tennis from day one and this stuff can

be taught and this is why they became

champions and this is obvious but this

is the same what you find with chess

champions and golf champions like Woods

and so on. Um you have to really spend

the time doing it. Now I find this

interesting for a few reasons. One is

that

cognitively you can understand how to

you know what a forehand or a backhand

you know is hit in tennis but to

actually get good at it you have to burn

it down into the circuitry. So actually

let me back up for one second which is

the reason that we have brain plasticity

is because this is how a brain makes

things that you do fast and efficient.

So when you're doing a task a lot like

you know serving tennis or something

you're taking that from the software to

the hardware of the brain let's say uh

I'm an amateur tennis player and and

there's Serena Williams I'm playing

against her. Um it turns out

surprisingly when we're playing she's

beaten me like crazy but my brain's the

one using all the activity. I'm the one

burning all the calories with my brain.

Why? Because she has burned tennis into

the hardware of the brain. So it's fast

and efficient. I, on the other hand, am

trying to simulate lots of things and

figure out where I should go and all

that. So the brain does this for reasons

of efficiency. Obviously the brain's

main job is to save energy because we

are mobile creatures who run on

batteries. And so um this is one of the

big things about about plasticity. So

people get extraordinarily good by doing

things over and over. the the these

these three women, the Polar sisters who

are chess champions. They're, you know,

the best to my knowledge are still the

best three female chess players in the

world. Their father from day one started

teaching them how to do chess and so on

and they all became uh world champions

at this. You know, the thing about

whether you need to have

diversification, that's an interesting

question. I can see why it would be

useful because you're learning different

ways, different moves about it in the

same way that if you learn how to

snowboard and ski, um, you know, you

might you might get better at both of

them. But I got to say, uh, when

children grow up, let's say,

triilingually, uh, or even bilingually,

they they end up having a lower

vocabulary in both languages than if

they grow up monolingually.

>> Really?

>> Yeah. It's just because of the amount of

practice you get with a language.

>> Kids, still do your uh second language

homework. [laughter]

>> In California, it's it's, you know,

growing up here, it's very useful to

know English and some Spanish.

>> I mean, very, very useful. In fact, I

wish I'd gotten better at Spanish when I

was a kid.

>> Uh, and my father's born and raised in

Wanosirus, but we didn't speak Spanish

at home, at least not very much. So, you

know, I can tell you learn a musical

instrument and learn a second language.

a musical instrument for your own

enrichment um and those around you. But

the the second language thing I think is

extremely useful at least in California

I find it to be really useful. But

>> kids are resisting this by the way now

because they say look I can do Google

translate or you know my meta sunglasses

and

>> so they're resisting it.

>> Yeah. But Google translate is not Google

relate.

>> I totally agree.

>> You know I I mean it's and I'm not I'm

hardly fluent but I can get by now. I'm

pretty good. But I've been practicing my

Spanish more and more and just by virtue

of living in Southern California, that

just happens. But I I think knowing a

second language um and being a to have

that kind of face tof face conversation

with someone, it's um even the struggle

of it is enriching in a way because

you're forcing your brain to do some

work.

>> My father spoke eight languages fluently

without accent. Uh and that's because he

went to medical school in Europe and did

his clinical rotations in different

countries and you know he was a young

man. So everywhere he went, he got a

girlfriend and then he had the incentive

to learn the language. And by the maybe

we'll come to this, but when it comes to

brain plasticity, the reward systems are

a big part of what makes change happen

in the brain. Actually, let me just

mention, this is tangential, but let me

just mention this while it's on my mind.

Um, you know, a lot of people really for

the last 30 years, ever since the

internet became a big thing, really

worried about what this is going to mean

for kids and education. I think it's

terrific. I am very optimistic about

this because

what what kids started getting a few

decades ago was this opportunity to

learn about something right when they

were curious about it. So they want to

know how to fix the bicycle tire or what

is this space physics thing or whatever

and they ask the question and get the

answer. Why does that matter? It's

because brain plasticity really happens

when you have the right cocktail of

neurotransmitters present and and that

cocktail happens to map on to curiosity

or engagement. when I'm I'm slightly

older than you are, but when we uh you

know, when we were in school, the

teacher teaches you the thing. They just

dump everything like, "Oh, the Battle of

Hastings happened in 1066 and you may or

may not ever need to know that." But

what kids get now is information right

in the context of their curiosity and

that makes a big difference because

stuff really sticks and I have been

extraordinarily impressed with young

people that I meet. I meet all these

young people who say these extraordinary

things. I say, "Wow, how did you know

that?" and they, you know, they've

watched TED talks, they've asked Alexa,

they've talked to ChatGpt and they get

the information and and it sticks. Super

interesting. I hadn't thought about it

that way. I uh I guess I'm reflecting my

age um to everyone when I say that, you

know, I remember being interested in

something and then having to bike or

skateboard down to Tower Books or go to

the library um and look things up. And I

tell myself that the effort involved in

going to get it actually is useful. But

you're right, had I been able to um kind

of look up what I was interested in and

get it right then, I probably would have

spent more time implementing the

information because I was interested in

all sorts of things that usually

involved building something or doing

something that was going to make a big

mess and frustrate my parents, right?

But I spent a lot of time searching for

the information. Yeah. Um, plus you

remember how dinner table conversations

used to go, which is that everyone

argues about something and then they

someone says, "Well, I think it's this."

And the other person says, "No, I think

it's that." And then it just sort of

stops there because no one knows the

right answer. But now everyone whips out

their phone, gets the answer, and then

and then it keeps going, which is really

terrific.

>> Yeah. It's dissolved um some of the

social dominance that comes about when

one person's word is the word that

everyone has to just kind of believe

just because they say it with more

certainty.

>> They're the father or whatever. Exactly.

>> Yeah. Or the grandfather or whoever. Or

the grandmother. in some cases, who

knows? Now, it gets checked against the

internet and uh uh claude for me or chat

GBT for for a lot of other people. I

realize that um the question I'm about

to ask can't be answered uh completely

but given what you know about plasticity

and the fact that yes you know we come

in to the world with some

pre-programming of our of our brain

circuitry but we have some control over

uh what the inputs are some depending on

our circumstances. It depends what you

mean by we. Uh, so as infants, of

course, we have no control over that.

>> As an adolescent, as a teen, as a

20-year-old, assuming plasticity extends

into adulthood, still as adults,

although it's harder, um,

>> some control over what one learns or

does. What do you think are um sort of

the core elements to uh making sure you

build a healthy, well-rounded nervous

system? Nobody's really ever attempted

to answer this question. you know, a

howler monkey learns all the things that

a howler monkey needs to do. Um, humans,

we have, as you said, the benefit of all

the technology that comes from the

plasticity of those that came before us.

And so,

>> you know, maybe kids don't need to learn

a second language, but what do you think

are sort of the the essentials? I mean,

obviously learning to communicate and

understand, learning to move, but do we

have some sense of of how you check off

the like the core 10 boxes of

neuroplasticity to make sure that by

time you land in adulthood or even if

you're still an adult that you're you're

doing the

>> quote unquote best that you can with

your brain? This is a tough question, I

realize.

>> I mean, I would say two things. One is

um you know, try to maximize along every

axis. So try to be an athlete, try to be

a scholar, try to be uh you know,

somebody who's good at social life and

has a lot of friends. All all of these

axes of life, it's worth spending the

time doing that. And if obviously we're

in an era, especially now, where there

are a million ways to waste time. I sit

on airplanes next to people and they're

playing Candy Crush for the whole

flight. And I just feel like what a

shame because there's so much you could

be putting into your brain and making

happen. You could be reading books, you

could be listening to podcasts, anything

like that. Okay. So, there's that. But

the other half that I would say is um a

lot of what we care to be depends a lot

on what's going on in the future. And

I'm fascinated by for children now in

schools,

what choices they should make because

who the heck knows what careers are

going to exist in 20 or 30 years from

now. Therefore, the main things they can

concentrate on, I think, are critical

thinking and creativity. Those are the

main things for them to figure out how

to do. What are some good ways in your

opinion to access critical thinking and

creativity? I I can imagine a number of

them.

>> Yeah. Here's something I find very

optimistic about AI in the realm of

education. Um,

you know, in any classroom, it's going

too fast for half the kids and too slow

for the other half of the kids. What we

now have the opportunity for is really

individualized education. One way this

could be implemented is AI debate. So

you take any hot button issue, abortion,

gun control, whatever you want, and you

debate with the AI and you get graded

based on the quality of your arguments

and then you switch sides and you take

the other side and you argue again. This

is the kind of thing you could never

have enough teachers for. They would

never have enough patience for. AI is

terrific at this. And by the way, it's

really important so that students get a

360 view of issues instead of

ideological capture. So this is a

terrific way to teach critical thinking

to every student, not just the kids on

the speech and debate team. Okay.

Creativity, that's easy. That has to do

with learning the foundational stuff and

then doing remixes, bending, breaking,

blending, doing new versions of it. And

I think schools can implement this

easily and without any extra expense

which is you have to teach the

foundational stuff but you compress that

so you have one extra week at the end of

each semester and then that last week

you say great take everything you've

learned and now make your own thing with

it using all the elements that we've

learned bend it break it blend it make

your own version of this. That kind of

exercise is that is creativity. That's

all creativity is is taking your

storehouse of knowledge and doing

remixes.

>> We should be teaching that.

>> So critical thinking and uh creativity.

Gerta the the German philosopher had

said uh there are two uh bequests that a

that a parent can give a child. One is

roots and one is wings. And my

interpretation of that has always been

critical thinking and creativity. Love

that and thank you for making it

practical. That's something I think any

and all of us could invest some more

time in. I also agree it's very easy to

waste time on on uh on the internet. Uh

I have a separate phone for social

media.

>> Oh, great.

>> That solved a lot of issues. Not that it

was really contaminating my life that

much. I like social media. I like

teaching and learning there and some

entertainment there. But by putting it

on an old phone, so X and Instagram are

just on that phone. It's amaz people

send me things by text and I I have to

transfer them over. Sometimes I see

them, sometimes I don't. My default

setting is no longer to just look at my

phone and look at social media.

>> Yes,

>> it has increased my productivity and

just my happiness and my level of

attention. Also, when I do social media,

that's I'm doing like a like a

purposeful like watching a show or doing

something that I would devote time for

is to not always just scrolling in the

background.

>> Do you find yourself picking up that

phone sometimes? Actually,

>> no. If I do, if I find myself doing that

reflexively, I have a uh what I call a

supermax prison lock box, which you

can't code out of. And the fun for me,

and get this, this is like really weird.

I don't know what this says about my

psychology. I'll put it in there and

I'll dial in, you know, okay, like 4

hours, and then I hit the supermax

button, and then there's this 15-second

countdown, and then I'll go 5, six,

seven, eight, nine hours. And I go,

okay, cool. Like 9 hours. So, there's

this weird thing where you don't want to

let it go, but then you

>> I really enjoy the freedom from it. so

much that the extra hours that I add on

and that last thing it feels like a gift

to myself and then I'm like I'm going to

have a great day and then when I get

back on it certainly there's this

dopamine dynamics thing where you go oh

this is a lot of fun but you have to be

super careful

>> because it'll suck you in. I'm just

amazed at how fast time goes which we're

going to talk about time perception. I

before we do that though, I I have a

question about plasticity that I've been

waiting to ask you and only you because

we have a lot of friends that are

neuroscientists, but I have a feeling

you've thought about this more than

anyone, which is are there any things

that we can do to extend the window of

plasticity? Or are there activities like

learning an instrument or or some sort

of game who knows that gives us our

capacity for plasticity uh more height,

more width um as opposed to just you

know the same principles. You need to

focus on the thing then you need to make

errors then you need to do some error

correction. You get to sleep that night

you rewire you trial and error. I mean,

we know that the basics now. I think

most people have heard them. But what

can we do to broaden our ability or

heighten our ability to get uh

plasticity?

>> Two words, seek novelty. That's the

whole game is you got to continually

challenge the brain. And this is

something that as we get older is more

important than ever. It's finding new

things that we haven't done before. You

always have to keep yourself between the

levels of frustrating but achievable.

And as long as you're trying new things,

so yes, a new instrument is great.

Speaking a new language is great. Um,

you know, obviously we're in a world

that's moving very fast. So just keeping

up with the technology and figuring out,

wow, there's this new opportunity here

with this piece of software, whatever.

All that stuff is great. This is the

critically important part. Um, you may

know these studies. There's been this

this study going on for decades now

called the the what is it? religious

orders study uh up in Chicago area where

there's a whole bunch of nuns and

priests that agreed to donate their

brains when they passed away. And then

when they donate their brains, the

researchers uh you know examine them, do

autopsies on them. What the researchers

found is that some fraction of these

nuns had Alzheimer's disease, but nobody

knew it when they were alive. Nobody saw

any cognitive deficits. Why? It's

because these these women died in their

90s.

And to the day they died, they lived in

these convents. And in the convents,

they had social responsibilities. They

had chores. They were fighting with

their sisters. They were playing games

with their fellow sisters. They were

singing songs. They were doing things

all the time. So they kept their brain

active. So even as their brain was

physically degenerating with Alzheimer's

disease, they were building new

roadways. They were building new bridges

over these areas. This is one of the big

things that tells us that uh you know

contrast this with with people who

retire at 65 and they go home and they

sit on a couch and watch the television.

They don't have as good an outcome

because they're not challenging their

brain anymore. Um so it is so important

to be doing things. You know I once

heard the expression that there's

nothing as hard that the brain does than

other people. And so for these for these

women living in convents, they were

constantly dealing with because you

never know what somebody's going to say

or how they're going to react or what

they're going to do. So this is great

challenge opportunity for the brain.

Anyway, the point is we need to always

find that with ourselves. Often times

people will ask me uh like an older

person will say, "Hey, I do cross word

puzzles. Is that good?" Yeah, it's good

until you get good at it and then stop

and do something that you're not good at

and constantly find the next thing

that's a real challenge for you. That's

the key thing about plasticity.

Essentially, the backstory is this. As

you well know, your brain is locked in

silence and darkness. It's trying to

make a model of the outside world. And

its whole goal is to make a successful

model. And when it succeeds at that and

says, "Oh, okay, wait. I I've got good

predictions about what's going on." Then

it stops changing. I That's its goal is

to stop changing. And if you're

constantly pushing and challenging it

with things it doesn't understand, then

it'll keep changing. Amen to that. I I

been trying to beat the drum that the

agitation that one feels when trying to

learn something new, it's actually a

reflection in in part of the

catakolamines, right? Like adrenaline

and norepinephrine, the frustration and

the agitation that we feel.

>> That's the feedback signal to the brain

that hey, this is different than the

stuff you know how to do. I mean,

because the neurons are not thinking,

they're firing, right? And so and so

that neurochemical millu associated with

frustration is one of the triggers that

uh generates plasticity which actually

you can resolve this question for me.

I'm struck by the fact that there's so

many studies showing that the adult

brain can change.

>> Yes.

>> And some of the more interesting ones um

involve boosting the levels of some

neurom modulator dopamine or

acetylcholine or norepinephrine or

epinephrine serotonin. But what's so

interesting to me is that seems like you

can boost the levels of any of those and

get plasticity. It's not like one neurom

modulator gives you uh the opportunity

for for plasticity. So many of the

interesting studies on psychedelics are

using psychedelics that are

>> kind of like serotonin. I mean they act

on different receptors, but they're very

serotonic. I I remind people of this

because people really like to um beat up

on SSRIs. And I agree they have their

problems and side effects, but they've

also helped a great number of people.

But whether it's SSRIs or psilocybin,

they're both just tools for plasticity

that drive serotonin. But we know you

can amplify acetylcholine, get a window

of plasticity. This is a speculative

question, but why do you think it is

that there's this sort of equip

potential of neuromodulators where

boosting any one of them can open

plasticity or the window or the

opportunity for plasticity?

>> Okay, a few things on this. as as you

well know you know all the neurom

modulators exist in a dance with each

other and and fundamentally I think

we're going to come to understand this

in 50 years as you know sort of

combination locks of things and the way

we keep looking at it in science

currently is ah here's acetylcholine or

here's serotonin or so and it's probably

not the right way to look certainly not

how the neurons are looking at it okay

that said acetylcholine really feels to

me like the main one involved in

plasticity when you are a Maybe you've

got acetylcholine going everywhere

whenever you're trying to figure out the

world. Whenever something's not matching

a prediction and you've got

acetylcholine going everywhere that

says, "Hey, I got to figure out what

just happened and how to link this with

what I did and so on." As you get older,

it's more like, you know, a pointalist

artist who just dabs things here or

there. You get to see the colon release

very locally in very in small places and

that's where you make changes. Why?

That's because as you get to be an

adult, you've got a better and better

model of the world. You don't want to

change everything. You just change like,

"Oh, I didn't realize there was that

button on the coffee machine that did

this new thing or whatever." So, you

just change little bits at a time here.

We're in this really interesting

situation in in the history of our

species where now we can do things like,

"Hey, what if we just crank up

acetylcholine or, you know, obviously

we've done lots of things with with

dopamine." Um, we always find when we

tweak these things that it's

complicated. Just as one example, you

know, with Parkinson's, people get have

less dopamine and so the medications are

to crank up the dopamine. What that led

to, you may know this fascinating story,

this probably 25 years ago now, where

you know, observant clinicians noted

that people on these Parkinson's

medications were becoming

hypercompulsive gamblers. They were

blowing their family's fortune on online

gambling and Las Vegas and so on. And

and what they realized is when you crank

up the dopamine that changes your risk

aversion such that people are taking. So

now it's a it's a contra indication

that's listed on the bottle. You know if

you notice gambling turn down the the

the the amount here. So anyway whenever

we whenever we start dialing these

around we always find things that are a

little bit out of our predictive realm.

Um, but uh the general story is that

your brain's trying to put together this

model of what's going on and as it gets

better and better, it's doing less and

less plasticity. I do want to point out

though that parts of the brain become

less plastic and others stay plastic

your whole life. As an example, your

primary visual cortex at the back of the

head that locks down early. You really

can't do much to change that. And um you

know there were studies by Logitus' lab

years ago where they looked at changes

to let's say the retina in an adult

monkey and they expected to see changes

in the visual cortex of the monkey and

they didn't see any changes at all and

that surprised them given all the

plasticity literature. But it's because

the visual cortex locks down. In

contrast, these downstream areas from

the visual cortex that care about things

like recognizing faces or new brands of

fast food restaurants or whatever it is,

those stay plastic your whole life

because there's constantly new data

coming in on those. So the general story

is the primary areas are like the I

think about it like the the software

kernels where you know if you're at

Microsoft for example there's parts of

the code that no one ever touches

because that's like how to add two

numbers and multiply whatever that's the

kernel of the code you never touch that

but you get these higher and higher

application layers on top of that and

that's essentially how to think about

primary sensory cortices and then all

the stuff downstream from there

>> perfect analogy I um for people to

understand, you know, how how much

challenge to embrace. I mean, you're not

trying to um, you know, defrag the whole

system, you know, and and and I

mentioned psychedelics. I, you know, I

do think they have some interesting

therapeutic potential. I I also worry

about and I can tell you examples of

people that got I guess now they

nowadays they call it one-shotted. They

take Iawaska a couple times and they are

forever different in ways that does not

serve them. those examples don't get

talked about quite as often as the also

many people who you know um seem to

benefit from these things. So um

plasticity it seems is not the goal.

Directed plasticity is the goal. That's

right. And it's very hard to direct. So

I feel like you know let's imagine you

could take some cocktail of

neurotransmitters and get total

plasticity of your brain. I don't think

you'd want that. You wouldn't be you

anymore.

who we are is the sum of our memories

and the sum of our skills that we've

built and you know that keeps changing.

We're always a moving target. Um and who

you will be in five or 10 years will be

different. But I don't think we'd want

the plasticity of an infant even though

when you're doing let's say language

learning you say I wish I could learn

this as well as I did when I was seven.

But uh generally it's not a state that

you would desire. I think

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to get started today. You've mentioned a

few times future self. I think uh all of

us are inherently interested in our

future selves and whether the things of

our past, present, uh and what we have

control over going forward is going to

put us in the best future self possible.

Right? Humans love to optimize or

fantasize about optimal. But how should

we think about thinking about our future

self? Or should we not do that? Right?

Should we should we should we just avoid

that loop-de-loop and um and uh get real

stoic about it and just live in

10-minute time blocks or one minute time

blocks? It raises a really interesting

question, I think, of where should we

set our time horizon

>> to not just feel the best, but to be our

best and to feel our best going forward.

>> Yeah. Our capacity to think about our

future selves is the most special part

of being humans. And you if we didn't do

it, if we said, "I'm gonna be stoked

about it." Yeah. You'd eat the the

cupcake and you do what? Like all the

things that wouldn't serve your future

self.

>> Never eat the cupcake like a real stoic

and then starve to death, right? Even if

the cupcake were the only thing,

[laughter] right? What would the stoic

do?

>> That's right. So, um, yeah, we actually

spend most of our time not in the here

and now. We're reminiscing about the

past and we're simulating possible

futures. Your your mind is a movie

theater. We're constantly thinking about

where things are going. But this is

great. This is what makes us able to do

all the things that that humans do

successfully. And in our own lives, this

matters so much because we're able to

think about who do I want to be? Now, as

you know, we've got this rivalry in the

brain. You've got all these voices going

on at the same time, all these different

networks running. So, for example, if I

put the cupcake down in front of you,

um, you know, part of your brain wants

to eat that. It's delicious. It's a rich

energy source. Part of your brain says,

"Don't eat it. You know, I I want to

stay fit." And so, part of your brain

says, "Okay, maybe I'll eat part of it.

Uh, but I'll go to the gym later." Or,

you know, I promise my girlfriend that

I'll go do this thing. What? Like, we've

got all these voices. You can cuss at

yourself. You can cajol yourself. You

can contract with yourself. And the

question is, who's talking to whom? It's

all you, but it's parts of you that have

these different drives. Now, the part

that's really amazing about us is we got

lots of short-term drives, but we also

have this capacity to look into the

future and think about who we want to

be. And that is essentially subserved by

our prefrontal cortex, which as we

mentioned earlier is something that is

a, you know, the size of it is unique to

humans. All of our closest cousins in

the animal kingdom don't have a

prefrontal cortex that's a fraction of

what we have. That's what allows us to

unhook from the here and now. Okay. Now,

here's the thing. I have been fascinated

by this for a long time about how we

sometimes know, okay, my future self is

going to act badly in this situation.

So, I'm going to do something now so

that my future self can't act badly. So,

this is the topic of my next book. It's

called the Ulisses Contract. And where

this term comes from is in the Odyssey,

Odysius, otherwise known as Ulisses, is

coming home from the Trojan War. And he

realizes that way up ahead, he's going

to pass the island of the sirens where

you've got these beautiful female

creatures who sing these songs that are

so beautiful it beggars the mind of the

sailors and and everyone crashes into

the rocks and dies. Ulisses really wants

to hear the song, but he knows like any

mortal man, he's going to fall for this

and crash the rocks. So what does he do?

He has his men lash him to the mass. So

he can't move. He has them put beeswax

in their ears so they can't do anything.

And and he tells them, "No matter what I

do, no matter how much I'm screaming,

just keep going. Just keep sailing."

>> Smart,

>> right? It's smart because what is

happening is the Ulisses of sound mind

is making a contract for the future

Ulisses who he knows is going to behave

badly. So he's lashing him to the mass.

And what I've been fascinated by is the

ways that we do this in our lives all

the time. So the example you gave a few

minutes ago about locking up your phone

in one of these lock boxes is a perfect

example because what you're making sure

is that the Andrew of two hours from now

can't do the wrong thing because you

know he might you know he's going to be

tempted. So you take away that

temptation. By the way, I recently met

uh an older gentleman who told me about

an older woman that he'd met years ago

who used to take her money, her cash,

and freeze it in a block of ice in the

freezer so that she couldn't spend the

money until she really needed it.

>> Yeah. I don't have a money spending

thing. And I actually have pretty good

control uh with with the phone and with

social media.

>> For me, there's also a I don't want to

call it a sick pleasure. There's a uh a

bit of a pleasure in knowing that it's

completely off limits

>> because it means I can't even look at it

for 10 seconds. I don't know. I think it

involves something over control of of

things that I feel like are trying to

control me.

>> Yeah. Exactly.

>> Which I do not like.

>> Exactly. Because you care about your

future self and you want future Andrew

to do the right thing.

>> So there are a million ways to make

these Ulyses contracts and I've been

studying this for years and I Yeah.

Anyway, so I decided to to write a book

on this because the way that we deal

with our future selves is just this

fascinating thing because your future

self is a little different than who you

are now. But with time, we come to

understand that our future self will

behave badly in different situations.

And so we just try to to cut those off.

I I'll give I'll give a couple examples.

One is it's super useful to get um

social pressure involved. So, for

example, I'm guessing you and I both do

this. You know, going to the gym is

something we enjoy, but it's really

useful to have a buddy where you say,

"Hey, I'll meet you at the gym at 8

tomorrow morning." And then even if you

wake up, you're a little tired, your

shoulder hurts, or whatever, you got to

go because he's going to be there. So,

getting social pressure involves a good

idea. I I I found this thing where it's

a a boot camp where you sign up for it

and every morning, you know, go jogging

together and do push-ups, whatever. But

if you don't show up, the group jogs to

your house and they stand on your front

lawn and they do jumping jack jumping

jacks and they scream your name until

you come out.

>> Amazing.

>> Yeah, it's really good to get that to

commit to that sort of thing so that

you're really going to show up. Um there

are ways to do this where you put money

on the line. So you can say, for

example, there was a woman who was

trying to quit smoking and she tried for

years to quit smoking. So, what she did

is she wrote a $10,000 check and gave it

to her friend and said, "If you catch me

smoking, I want you to donate this check

to the KKK, which to her was the most

aversive thing that could ever happen

with her money." And that's what

prevented her from smoking because the

sting of knowing that she gave her money

to the KKK was the worst thing that she

could imagine. So, there are a million

ways to do these Ulisses contracts, but

what they have in common is how do you

lash yourself to the mass so you'll keep

the good behavior you want?

Yeah, the example of this woman writing

the check is interesting because um

I could ask why couldn't she access her

inner clearly has a lot of inner fight

right like she really stands so strongly

on one camp which um I agree the KKK

horrible organization would never want

to support them in any way uh whatsoever

and um and yet she needed to do that

right she needed a punishment a

potential punishment

And so it speaks to how even if we know

something and feel something so strongly

in the present,

>> yes,

>> it still becomes very hard to um to

access our best choices.

>> Yeah.

>> Um but there's something about the

future self that we're not even in yet

that we fear our future self so much

more than than we uh can't handle the

the discomfort of our present self. It's

almost like and so we tether those in

this Ulyses contract.

>> Yeah. It's a kind of wisdom that we come

to understand how we will behave when

we're not in our present, you know,

sober, rational moment. Um, we come to

understand, for example, people who are

trying who are alcoholics and they're

trying to break that. The first thing

they're told at, um, Alcoholics

Anonymous is clear all the alcohol out

of your house. Because you might think,

okay, I'm done. I'm firmly going to not

drink anymore. So, you put the alcohol

away up in a high shelf. But on a

festive Friday night or a lonely Sunday

night or something, you might go up

there. Your future self might do that.

So what you do is you get rid of the

temptation. Same thing with people who

are trying to battle drug addictions.

They're told, "Never carry more than $20

of cash in your pocket because at some

point you're going to run into some guy

who's trying to sell you drugs and if

you got the money, it's burning a hole

in your pocket. You buy the drugs." I

don't think we can trust our future

selves. When we're in a moment of

reflection and we can think about who we

want to be, it's worth setting into

place some walls.

>> So that's about avoiding uh bad

behaviors. Um what about building toward

future self where we're trying to

envision a better version of ourselves

that involves actively doing things. So

there's always dos and don'ts in order

to become our better self. Um, how does

Ulys's contract play in when it's not

about the sirens? When it's about um

knowing that we want to be

this person or have these attributes or

having done something and trying to tie

our future self to our present behavior,

how good are we at that? Um, in general,

>> yeah,

>> better or worse than avoiding bad

behavior?

>> Oh, we're terrible at all this stuff. I

mean, take New Year's resolutions. I

mean, everybody makes New Year's

resolutions. they rarely last a week or

two before they drop off. People get

busy, people get tired or whatever. Um,

so it's just as important with the

positive things to hook things to that.

Um, for example, this idea of putting

money on the line. There are various

websites where you can do this. You say,

"Okay, look, I'm going to put, you know,

50 bucks on the line that I want to be

able to bench 250 by this date or

something like that." Um, and then

you've given your money to this company

and you have to get to that point. So,

you get your money back. Um, there are

lots of ways to do this. Um, you know,

obviously putting, you know, I think you

had James Clear on a little while ago

and and there there's all kinds of good

uh ideas that he's got about, you know,

put your running shoes near the door or

whatever so that it's easy. You get the

you get rid of the friction to go do

things like that. But all of those moves

are for your future self. When you put

your shoes near the door before you go

to sleep that night, you are doing

something because you know your future

self's going to be a little bit lazy and

tired.

>> I have friends that are uh I'll just

call them what what I would call them to

their face because it's a friendly

exchange. Are are kind of neurotic,

right? They tend to overthink things. If

they're going to go running at 8 a.m.

and it's 8:02, they're like, "I can't go

because it's 8:02, not 8. I'll go at

9:00. Got to do it on the hour." This

kind of thing. And then I know people

who are like you just do things and you

don't think about it as much and they're

good at suppressing that voice. Um I

think we assume that the the chatter the

the neurosis doesn't exist for them but

I think um I think it does. They're just

better at saying like like ignoring that

inner voice. Um

>> we're never trained how to do this.

We're never taught as kids here's when

you need to really think and deliberate

and here's when you just need to just do

it.

>> Yeah. And it's interesting to think

about, okay, different career paths,

different life requirements, and so

forth. But, um, I feel like people fall

into kind of two camps with this. Some

people need to think and analyze less

and do more. And some people actually

need to, you know, probably still do,

but maybe think a little bit more about

their behavior and reflect a bit more.

And they would probably both say, "I'm

crazy about this." Um, I won't tell you

where I land. I think I'm kind of in the

middle. No, I'm just kidding. Um,

[laughter] it depends on on what's at

hand. Yeah.

>> for most people I think. Um

>> what do you think that's about the

ability to suppress the various versions

of oneself or not?

>> The inner voice.

>> Yeah. You know, I would say one of the

most fascinating things we've discovered

in neuroscience to for my money is is

just this issue that along anything we

measure there's a spectrum. So just take

something like the internal voice. Uh

for my wife for example, she describes

it as her inner radio. She's always

hearing her inner voice. I I don't

really have one. I just never hear that.

So, we're on opposite ends of the

spectrum that way. But, you know, one of

the things I've studied is um aphantasia

all the way to hyperfantasia. That means

when you know, if I ask you to visualize

an ant crawling on a tablecloth towards

a jar of purple jelly, some people see

it like a movie in their head. That's

called hyperfantasia. Some people have

no picture at all in their head. That's

called aphantasia. And everywhere is

everyone is somewhere in between on the

spectrum.

>> What does the middle look like? So, if I

do that, if I maybe everyone can do this

right now. It's a a fun experiment. If

you're driving, don't close your eyes.

Um [laughter]

>> uh

>> picture sun coming over the mountain and

the rays of the sun poking through the

clouds

>> and then it starts raining and rains

coming down.

>> Mhm.

>> So, the question is, do you see it as

clearly as a movie or do you have really

no visual anything in your head or are

you somewhere in between? Typically,

this is judged on a scale from one to

five where five is a movie, one is no

visual at all and, you know, three is in

between. Where where do you stand on

that?

>> I feel like I can see it quote unquote

um in my mind's eye, but um it's almost

like I'm looking at a silhouette of it.

So, even though I want to see bright,

you know, rays of sun, sunshine, one of

my favorite things in life. I know

they're there, but they're actually pale

pale yellow, it's almost as if it's more

opaque than it would be in real life.

>> Yeah. You're saying people with it with

hyper hyperfantasia see it as a same way

I would on a on my phone

>> essentially. Yes. They're seeing it like

like vision. Now I happen to be

aphantasia. So it's very hard. You know

I've studied this for years. I've

interviewed hundreds of people on this

and so I get their description but I

can't I can't picture that myself. By

the way it's an interesting quick

tangent. Um for years I've talked with

Ed Catmol about this. Ed Catmull is the

guy who started Pixar. Pixar with all

these terrific animated films and so on.

Um Ed has all these patents on like how

to do ray tracing to get the you know to

get these animated characters looking as

amazing as they do. He was surprised

when he discovered that he was

afantasic. He doesn't picture anything

in his head. So he ended up giving this

questionnaire to everybody at Pixar. And

it turns out most of his best directors

and animators are aphantasic. They don't

see anything in their head. And nobody I

think would have predicted that because

it seems so strange this visual,

you know, magisterium of of Pixar. But I

I have a hypothesis about why this is.

It's because the kid who grows up who's

aphantasic,

when they're asked, "Okay, draw a

horse." You know, the kid sitting next

to them who's hyper fantasic says, "Oh,

I know what a horse looks like." And

just draws it. But the poor aphantasia

kid has to really stare and figure out

like that, okay, how does that work? And

so on and and they get better at drawing

as a result. That's why all his best

animators and drawers are people who

grew up a fantasic.

>> Interesting. I'm just uh thinking about

that movie. Have you seen that movie Bow

Finger?

>> No.

>> With with Steve Martin and uh Eddie

Murphy, which is Bowfinger is the you

know, for those just listening, it's

where you put kind of make two uh you

know L an L and and a sort of reverse L.

And it's like how you know it's about

making a movie in LA and uh it's it's

hilarious. It's it's spectacularly

funny. It's got those two folks I just

mentioned, Heather Graham, a bunch of

other people, but but he's constantly

going around and kind of envisioning,

you know, that this is the movie. This

is the movie. Exactly. And so I always

thought people that make movies are

going through life thinking, okay, like

there's the shot and there's the shot.

But I think what you're saying is that

there's somewhere in between where

people have this kind of fantasy life of

like, okay, here's this um here's the

script and then um they can't really

imagine it and so they have to put more

work into uh materializing it.

>> Yeah.

>> Okay. Well, they have a dialogue with

the page. So, if you're a guy drawing

and you know you're looking at the horse

or you're picturing what you know, Ariel

the mermaid looks like or whatever,

you're you're trying lines and

scratching and doing things, you don't

come to the table always saying, "Oh, I

know what a mermaid looks like." And you

draw it. Um, so they just end up getting

more practice and they get better at it.

>> I love this stuff because what we're

really getting at here is um, you know,

I think as you mentioned, everyone has

kind of individualized hardware and

software, but there are some

commonalities. And you know, wouldn't it

be spectacular if we knew, you know,

which you know, just like we learned,

okay, here are the macronutrients and

you perhaps want them in different

proportions depending on who you are and

what you need and, you know, and uh you

need to, as a kid, you should probably

learn how to like climb and run and, you

know, and assuming you have access to

all of that, you know, and um and jump a

little bit, but you know, maybe you

won't be an athlete, but you need to

like be active at some point and then

you be and we tend to figure out what

we're good at and then really lean into

those trenches and then by then we're

getting evaluated for it and the way

we're evaluated puts us on a career

track and there's very little

opportunity to go back and kind of fill

in blanks. Um, right there's, you know,

I I'm never going to be a musician in

part because I'm just not willing to put

in the work because there are other

things I'd rather do with my plasticity.

Right? So, um, and maybe that's best.

So, big big picture question. Um do you

think that

human evolution and the progress of

building technologies

um reflects the fact that people get

siloed into um different tracks and on

the whole that's advancing our species

right you've got people that are hunter

gatherers still very good at that and

building and other people building

weaponry and other people building AI

technologies and that that it would be

uh detrimental to our species if

everybody got sort of core

neuroplasticity training, learning how

to do a little bit of everything, right?

Um, or is that the the what we see as

chance actually part of the reasons why

humans are the curators of the earth?

Not just the prefrontal cortex, not just

the extended window of plasticity, but

how we are afforded different

opportunities to work with that

plasticity.

>> Yeah, I'd say a couple things. One is

we're clearly predisposed to particular

things. And so, for example, I'd like to

be a swimmer as good as Michael Phelps,

but I just don't have the wingspan that

he does. is he's got like I don't know

seven feet between his fingertips or

something. Gez, there's no way I'm going

to be able to be as good as he is. Um

that's a genetic thing that he drops in

the world with that I don't fine. Um so

given that people are off on different

trajectories anyway, the way I think

about this, I don't know how this will

translate just in terms of audio, but

like a space-time cone in physics is

where you start in one spot and then

there are all these different

trajectories you can take into the

future. Picture this like you're

starting at the bottom of the ice cream

cone and you can you you can take any

different trajectory as long as it still

exists within the ice cream cone. Okay.

So, um you know, we drop into the world

with our genetic skills and

predispositions. We have childhoods that

we don't choose. We're born into a

cultural language and era that we don't

choose. And that defines the limits of

the ice cream cone about where we can go

with that. As far as specialization

goes, you know, economists will argue

this is part of what makes a very

healthy society is that, you know, some

people become the lumberjacks and some

the lawyers and some the accountants and

whatever. Um, you know, I do feel like

we're in a really great era though in

general in humankind where kids do get

very broad educations and they're sort

of encouraged to try everything and

spend a few years in karate and in

soccer and in piano lessons and so on.

That's wonderful. So the my father was a

psychiatrist and he always said really

the whole job of a parent is just to

open doors for the child. That's it. So

you give the child all these lessons,

you open all these doors and then the

kid takes their own path depending on

you know this extraordinarily

complicated formula of things that we'll

never understand but they go through one

door and not the others. Kirkagard said

every man starts as a thousand men and

dies as one. And what he meant, of

course, was that you start with all this

potential. You could do all you could

have been a great saxoponist or

whatever, but you're going to die having

done exactly what you did and and not

the other path. So, what's weird about

life is that yeah, every door that you

choose, some others close as a result.

>> Kirkard uh seemingly understood that the

nervous system starts out hyperwired and

then a lot of learning is the pruning

back of connections and strengthening of

the remaining ones.

>> That's exactly right. Exactly right. You

know, so as you of course know, the the

brain starts out, you got essentially a

fixed number of neurons. There's some

debate about whether there's a few new

neurons born in humans or not. Put that

aside. What happens is over the first

two years, those neurons connect more

and more and more and more. And what you

end up getting is this hyperconnection

by the time you're two years old. And

from there, it's just a matter of

pruning an overgrown garden. And that's

all that's happening. And and the way

the pruning happens is based on what

you're experiencing in the world. the

world is what prunes your garden and and

strengthens particular paths and lets

other paths go

>> as a bridge perhaps between plasticity

and time perception which we've been

sort of doing already. Uh I have this um

practice that I've been doing for a few

years um in hopes that it's beneficial

for something and I I just like your

thoughts on it. Um I'm not looking for

approval here uh truly but here's the

idea. I was struck by the somewhat

obvious thing that, you know, we can

close our eyes, uh, focus on our

interosception, our skin, our breathing.

We can meditate, bring our awareness,

you know, into the quoteunquote present.

The breathing is seems like a good way

to do that. Um, or we can open our eyes

and we can focus on something some

distance away. Or we can imagine the

pale blue dot and we're just this little

thing running around on this pale blue

dot. And you know when we move through

those different uh realms of space, not

just outer space, but from body to out

of outside our body to outer space,

there's a different time association

with each of those. And I' I'd like your

thoughts on that. And I I just started

devoting a little bit of time to

stepping from one of these to another

and just spending some time trying to uh

think and exist in the different time

domains um in my head. And so I'll do

that maybe for 2, three minutes or four

minutes or five minutes. And I told

myself, and I still tell myself, that it

affords me some flexibility when

something's happening in the moment and

you want to get perspective. It's about

getting out of that time domain and

realizing this isn't going to go on

forever even though it feels like it.

So, I developed this as a bit of a

practice for myself.

>> Um,

>> because I I felt like it's just a it's

not a meditation. It's a perceptual

exercise. Um, so what I'm curious about

is the relationship between time

perception and where we place our

attention. That's the first question.

And then you know maybe what we can do

with this or or could we evolve this uh

perceptual exercise so that um I and and

others perhaps if they want to can start

to access different um space-time

representations which sounds so fancy

but it's really just a way of like

getting outside yourself or getting

within yourself. Sorry if I'm being um

choppy here but but this is something

that feels very important.

>> I I love that. I think that's brilliant.

Um, one of the things that is so

striking about time perception is that

you don't have a single part of the

brain that deals with that. You actually

have different mechanisms that deal with

thinking about long eras of time and

seconds and subseconds. Um, totally

different mechanisms going on here. Uh,

and and we can demonstrate this in the

laboratory. So, time perception is

something I've been studying since

graduate school. And um you know I'm

happy to say I've got papers in science

and nature and you know the top journals

on this topic. Why? Because it's such a

weird thing that's so understudied about

how why why we perceive time the way we

do. So um let me say a few things about

it. One is that it is a these longer

time scales what you're referring to

thinking about being uh far away in

space and time. This is a cognitive

development. children can't do this well

and they learn better and better. So,

for example, if you talk to a a seventh

grader and you talk about the Roman

Empire and what was happening 2,200

years ago, it's re it doesn't mean

anything to, you know, it's like, okay,

so that's the past and whatever. But as

you get older, if you become, let's say,

a professional historian, you get better

and better at understanding that. Why?

because you've lived decades and so now

you can sort of think you can sort of

feel what a century might look like and

you can sort of with practice get better

at at these things. But the point is

that is something we learn how to do

both in space and time. Obviously when

you're an infant in the crib, space is

just a really close thing and eventually

>> it's your whole world.

>> It's your whole world and eventually you

get outside and you look down long

highways in Utah and you you you really

start getting a better sense of this.

Um,

I I to my knowledge there's no data on

on what it would be to to sort of throw

yourself back and forth between these

different space-time uh scales. I love

it though. One of the classes I teach at

Stanford is called the brain and

literature. Uh, I've always been a lover

of literature and one of the things that

I love is when authors do exactly this

where they they zoom in on something

really tight and they're really paying

attention and then they zoom way out.

That is the most extraordinary sort of

feeling. Um, so anyway, I commend you on

coming up with that version of

space-time meditation or whatever it is.

That's very smart. Yeah, it was um it

was born out of this thing, you know,

the the Victor Frankle thing like

between stimulus and response, you know,

and but there's something about the

autonomic nervous system like when we're

in a heightened state of stress. Um

we're not good at getting outside of the

moment, you know, people like take 10

breaths or whatever and it wasn't that I

was having struggles with that. I just

thought so interesting like you watch a

movie and it seems to be placed in a

different time domain in each scene or

um and you know then you go for a walk

or a hike and I I have this obsession

with the idea that when we see horizons

we have a different time perception than

when we uh can't see horizons um and

there's too many variables to do this

right you could do it in VR in a VR

experiment but um because when there are

close walls you have claustrophobia but

there there ways to do this correctly

how you change your your your vision or

visualization changes your time

perception. So, I don't know. I just

look at it as a flexibility exercise.

And um and I'm a scientist and a weirdo,

so I I I do these things. Um but uh

you're the expert in time perception.

So, I wanted to ask um and I also want

to ask about time perception. Um how

good are people at perceiving time? And

um why am I always late? [laughter]

>> The why are you always late? That has to

do with Ulys's contract thing, which is

just it it requires a commitment to say,

I'm going to be the kind of guy who's

always on time. And the way to do that

is to say, I'm going to commit to always

being five minutes early. So, you get to

a place early and you just hang out in

your car and you, you know, take care of

some texts or whatever. That's the way

to be always on time. Okay. But are

people good at perceiving time? No.

We're actually quite terrible at it. Um,

and some people are better than others.

But one of the lessons that's emerged

from my research on this stuff is that a

lot of time is is illusory. Um, so you

you may know I did this experiment years

ago. I was very interested in this

question of does time run in slow motion

when you're in fear for your life?

Because when I was a child, I fell off

of a roof of a house. I almost died. I

landed on my I landed in a push-up

position and busted my nose so badly

that they had to remove all the

cartilage and so on. And I've had a

terrible sense of smell ever since

because I busted the cri cribopform

plate and everything. But the part that

interested me even as a child was that

the whole fall seemed to take so long.

It felt like, oh my god, that was this

really long thing. Obviously, I was

totally calm during it. I was thinking

about Alice in Wonderland as I was

falling and how this must have been what

it was like for her to fall down the