0:00

This is Hidden Brain. I'm Shankar

0:02

Vedanta. In March

0:04

2020, a few weeks after COVID-19

0:06

lockdowns began in the US, we

0:09

asked listeners to send us voice memos about

0:12

their experiences of the pandemic. We

0:18

recently went back and listened to those messages, each

0:21

one a tiny time capsule of

0:24

life in a world under lockdown. Listeners

0:26

told us about the stress of trying to

0:29

find toilet paper and masks. They

0:31

talked about the challenge of trying to work over Zoom. And

0:34

more than anything, they grappled with

0:36

the sudden, shocking ways in which

0:38

their lives had become smaller and

0:41

more isolated. I don't

0:43

know if I could live with myself if I was stuck

0:46

here and something were to happen to my

0:49

grandma. And this is especially apparent

0:51

when I found out that I

0:53

could not visit my father in

0:55

his independent living facility. My older

0:57

sister gave birth to her son.

1:00

We weren't able to be with her at

1:03

the hospital, nor have we

1:05

been able to see him. In

1:17

those early days of the pandemic, so many

1:20

of us found ourselves dreaming about what it

1:22

would be like when we could once again

1:24

hug friends and family outside our immediate household.

1:27

We fantasized about the moment when we could enjoy

1:30

going out to a restaurant or a music venue.

1:33

We told ourselves that we would not take

1:35

those moments for granted once we

1:37

had them back. And

1:41

indeed, the first time I got to see

1:43

relatives overseas and enjoy dinner out with friends,

1:46

it was truly amazing. The

1:48

second time was pretty great as well. But

1:51

after a while, that magical

1:53

feeling inevitably started to fade, no

1:56

matter how hard I tried to hold on to it. We

2:00

see this in many dimensions of our lives. So

2:03

many love stories end at the

2:05

point at which great romantic quests

2:07

are consummated. Stories that

2:09

follow lovers past the wedding day into the

2:11

years and decades of their marriages, those

2:14

tend not to be romantic comedies. It's

2:20

easy to be cynical and say that nothing

2:22

lasts, that everything fades away. But

2:24

this belies what actually happens in

2:26

our minds as we experience triumphs

2:29

and setbacks. This

2:32

week on Hidden Brain, the

2:34

psychology of habituation. How

2:37

we get used to both the good and the bad in

2:39

our lives and the surprising

2:41

implications it has for

2:43

happiness. Support

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Lufthansa Allegris, it's your journey. It

3:20

all starts with a yes. Think

3:27

about the last time you saw one

3:29

of your favorite desserts on a menu. Maybe

3:31

it's the restaurant's signature

3:34

chocolate cake. Your mouth waters

3:36

as you read the description and you

3:38

order a slice, gleefully anticipating how good it

3:40

will taste. The

3:43

first bite does not disappoint. It's

3:45

out of this world. As you

3:47

continue to dig in, however, something

3:50

funny happens. The cake no longer blows your

3:52

mind. The cake

3:54

no longer blows your mind. You

3:56

lift your fork to your mouth a few more

3:58

times, trying to recapture the memory. magic of that

4:00

first bite. But it's no

4:02

use. What had

4:04

been unbelievably delicious minutes earlier is now

4:07

merely pleasant. What

4:10

explains this? More importantly, what

4:12

can we do to make the

4:14

second half of that slice of cake taste

4:16

as good as the first? These

4:20

are questions that animate cognitive neuroscientist

4:22

Tali Sharat at University College London.

4:25

Tali Sharat, welcome back to Hidden Brain.

4:28

Thank you. It's a pleasure to be back. Tali,

4:31

you did some research in a resort in

4:33

the Dominican Republic. Can you describe the setting

4:36

for me and what questions you asked the

4:38

people who were vacationing there? Yeah,

4:40

so I was working with a big

4:43

tourism company. And what they wanted

4:45

to know is what makes people

4:47

happy on vacation and when are

4:49

they the happiest on vacation? So

4:51

we did surveys and we actually went out to the resorts

4:54

and we talked to people. And

4:56

when the data came in, we found two

4:58

really interesting things. The first was that the

5:00

holiday makers were the happiest 43 hours in.

5:04

Why is that? Well, 43 hours allowed

5:06

them time to get settled and unpack. So

5:09

they could really concentrate on fun. But

5:12

after that, happiness starts going down, right? Less

5:14

and less joy. Now, to be clear, they

5:16

were always happy. But on day eight, they

5:18

weren't as happy as they were in day

5:20

seven, day seven, not as happy as day

5:22

six, and so on and so forth. And

5:26

the second thing that we found is that

5:28

when we asked them what was the best

5:30

part of the holiday, there was one word

5:32

that they used more than any other

5:35

word. And that word was first. The

5:38

first view of the ocean, the

5:40

first cocktail, the first sandcastle,

5:42

the first dip in the pool. Firsts

5:44

were exciting and new. The

5:46

second dip in the pool was also good, but it

5:48

wasn't as good as the first. And

5:51

this is really, I think, a great

5:53

example of habituation, right? When you see

5:56

the ocean, it's wonderful. And

5:58

the second time you see it, it's still wonderful. but

6:00

it's not quite as wonderful as

6:02

the first time. Things

6:04

that are around us all the time,

6:06

that are constant or that are frequent,

6:08

we just respond less emotionally, and even

6:10

perceptually, we respond to them less. So

6:22

psychologists have found the same phenomenon

6:24

happening not just among people eating

6:26

dessert or going on vacation, but

6:28

in relation to the most significant

6:30

events of life, like getting married.

6:33

What does the research show about happiness levels

6:35

among newlyweds? Happiness

6:37

actually goes up when people get married, on

6:40

average, but then it starts going

6:42

down and down and down and it reaches

6:44

baseline level, that is the level that before

6:46

they got married, in about two years. And

6:50

also attraction to

6:53

their partner goes down over

6:55

the years. I

6:57

mean, this is why so many Hollywood

6:59

movies end with the wedding or even

7:01

the first kiss. Yes, yes,

7:03

absolutely. But

7:06

as we habituate, meaning we

7:08

respond less to things like to the

7:10

view of the ocean, we also respond

7:12

less to our new love,

7:14

right? What is

7:17

around us constantly just doesn't really

7:20

gather our attention as much, right? And we kind of,

7:23

we don't attend to it, and so we

7:25

don't really focus on it

7:27

as much, and it doesn't really spark

7:29

that kind of joy and excitement than

7:31

it did at the beginning. So

7:35

as I was reviewing this work, I could think

7:37

of all kinds of things in my own life

7:39

where I feel I have habituated to things. The

7:41

same must be true for you, Tali. Can you tell

7:43

me about some things that you have habituated to? Yeah,

7:47

absolutely. Probably to almost everything, I would

7:49

say. You know, even

7:51

my work, right? I mean, if

7:53

you think about when you

7:55

first got your first job entry-level

7:58

position, it is really exciting. and

8:00

you, right? But

8:02

after a while, you kind of get used

8:04

to it. And even if the job is

8:07

your dream job, and it's really meaningful work,

8:10

over the years, it doesn't

8:12

seem that interesting.

8:14

It doesn't seem that exciting. Tali

8:23

experienced this acutely after buying the

8:25

house she lives in. We

8:29

moved into this house in the middle of

8:31

the pandemic. So we have two kids, and

8:34

we were living in

8:36

the city, in a place that

8:38

was a little bit too small, I think, for

8:40

a family of four. But it

8:42

was fine before the pandemic because we weren't

8:44

in the home at all times. But of

8:46

course, then the pandemic started, and so all

8:48

of us are at

8:50

home at all times, the kids are studying

8:53

at home. And so we moved to a

8:55

much more spacious place outside of the city.

8:58

And when I

9:00

first moved, it felt

9:02

just the perfect place to

9:05

be. And it really brought me a lot of joy.

9:07

Everyone had a room for themselves

9:10

and also had a garden

9:12

and there was trees and greenery. So you

9:14

look out of the big windows and you

9:16

see all this green, which makes you feel

9:18

happy. And

9:21

it still does. But of

9:23

course, I got used to

9:25

it. And so the reaction

9:28

is less and less and less. So

9:34

we've talked about this phenomenon on hidden

9:36

brain before. Psychologists sometimes call this the

9:38

hedonic treadmill. For listeners who are unfamiliar

9:40

with the term, can you explain what

9:43

that is? And also the links to

9:45

this larger phenomenon you've been talking about

9:47

called habituation. Yeah,

9:49

so the hedonic treadmill is this idea

9:51

that people have a baseline of happiness

9:53

and some people

9:56

could be a little bit happier than others.

9:58

We can go, you know. do

10:00

something that makes us happy, get married, get a

10:02

nice job. But eventually, we

10:04

will kind of slowly, slowly go back

10:06

to this baseline. Also, bad things happen

10:08

to us. It could be really bad

10:10

things. Lose a loved one, lose your

10:12

job. And we would, of course, feel

10:15

much worse when those things happen.

10:17

But then eventually, slowly, slowly, slowly,

10:19

we go back to our baseline.

10:23

So that's basically the hedonic treadmill.

10:25

But I think the phenomena that

10:27

we're talking about, habituation, is it's

10:33

related. But it's not quite

10:35

the same. It is much, much

10:37

broader. Habituation means

10:39

that we just respond to anything that

10:42

is around us, anything visual or smell.

10:45

So for example, you go into a room, and

10:48

you really smell, let's say, roses. Within

10:51

about 20 minutes, you won't be able

10:53

to perceive the smell of roses because

10:55

your olfactory neurons will just not respond

10:57

anymore. Or

10:59

you hear the noise of the AC in

11:01

the background. And it

11:04

could be quite irritating at first. But very

11:07

quickly, you just don't notice it anymore. So

11:10

these are perceptual examples, but are emotional

11:12

reactions to things. It could be a

11:14

dog barking. It's like the neighbor got

11:16

a new dog, and it's really scary.

11:18

And we have a fear reaction, but

11:20

the second time, less so. And the

11:22

third time, less so. There's perceptual habituation.

11:25

There's emotional habituation. And

11:28

it has a lot of implications beyond

11:30

the hedonic treadmill to our

11:32

personal life, but also to society.

11:36

So why does this happen, Tali? Why is it

11:38

that the brain habituates to things? At a

11:40

fundamental level, it seems like it's a property

11:42

of the brain. Why does this happen? So

11:46

there is an evolutionary advantage. The

11:49

brain has limited resources. And

11:51

so once we've processed

11:53

something, then it's really time for

11:56

the brain to keep

11:58

the resources for the next. thing that is

12:00

coming our way. So

12:02

imagine there is a dog, and the dog

12:05

is in the rose garden, and the smell

12:07

of roses really fills its nostrils. It

12:10

is helpful that after a

12:12

while, the olfactory neurons will just stop

12:14

responding. So now we have all the

12:16

resources needed for the dog to be

12:18

able to smell a coyote that is

12:20

coming its way. So we need

12:22

to be prepared for these frets that are coming

12:24

our way. So we need the resources, but also

12:27

for the good things. There's

12:30

a cookie somewhere

12:32

in the distance that the dog should

12:34

go and get. So that has an

12:36

evolutionary advantage, but it also keeps us

12:38

motivated. So if you think back to

12:40

your entry-level job, and you were

12:42

super happy about it, imagine you stayed super

12:44

happy forever. You will not be

12:46

motivated to get to the next promotion,

12:49

to get to the next job. You'll

12:51

just stay where you are. So we

12:53

need habituation in order to evolve as

12:55

a person, but also as a society.

12:59

And maybe the third important factor

13:01

is well-being

13:03

and mental health. So

13:06

what has been shown is that people with

13:08

mental health problems, for example, depression, tend

13:11

to habituate slower. People

13:13

with depression, when negative things happen,

13:16

they don't bounce back as fast. There's

13:18

a great study that was conducted by

13:21

Professor Aaron Heller from the University of

13:23

Miami, where he asked students who

13:25

just got a score on a really important test how

13:27

they were feeling. And then 45 minutes later, he asked

13:30

them, how were they feeling? And 45 minutes later, how

13:32

they were feeling, and did that for the rest of

13:34

the day and the next day. And

13:37

what he found is that those

13:39

without a history of depression

13:42

and those with a history of depression, they all

13:44

felt really bad at the beginning if

13:47

they got a bad grade. But the

13:49

difference was that those that did not have

13:51

a history of depression, they were back at

13:53

baseline, right? They

13:57

were doing their things, going

13:59

out. But those with a

14:01

history of depression or current depression,

14:03

they tend to ruminate. They

14:06

weren't able to go back

14:08

to just their level

14:10

of well-being that they were before, right?

14:13

They were kind of stuck and habituated much, much slower. You

14:17

say that in order to survive and reproduce,

14:19

we need to prioritize what is new

14:21

and different. So the sudden smell

14:23

of smoke or a rustle in the bushes

14:26

that could signal a lion or a predator,

14:28

you know, an attractive potential mate who

14:30

passes by, you say to make the new

14:32

and the unexpected stand out, your brain filters

14:34

out the old unexpected. So in some

14:36

ways, this is really a fundamental property of

14:39

the brain that's really been designed through millions

14:41

of years of evolution. Yes.

14:45

And habituation is something that we could see

14:47

in all animals,

14:49

whether it is a rodent or a

14:51

dog or a fish. And

14:53

in fact, we can see something very

14:56

similar, what we call neural adaptation in

14:58

even bacteria. So

15:01

this is something that goes way, way, way

15:03

back and is really

15:05

fundamental. I mean, every neuron

15:07

in our brain habituates.

15:17

Our brains painstakingly construct models of what

15:19

the world is like. When

15:21

reality conforms to that model, we don't

15:23

react or even notice it very much. When

15:28

we come back, how to step off the

15:30

hedonic treadmill and feel the goodness of good

15:32

things again. Also, we'll

15:34

explore the flip side of the hedonic treadmill,

15:37

the way we habituate to things

15:39

that are scary, shady and

15:42

sad. You're listening to Hidden

15:44

Brain. I'm Shankar Vedanta. Support

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conditions apply. This

17:06

is Hidden Brain. I'm Shankar Vedanta. Tali

17:10

Sharat is a cognitive neuroscientist at

17:12

University College London. With

17:14

Cass Sunstein, she's the author of Look

17:16

Again, the power of noticing

17:18

what was always there. Tali,

17:21

you've told us how the process of

17:24

habituation can diminish the pleasure

17:26

and satisfaction that an

17:28

event or an experience might once have

17:30

given us. You say that there's

17:32

a solution to this that you call dishabituation.

17:35

What do you mean by the term? So

17:38

dishabituation means starting to respond again

17:40

to something that we stopped responding

17:43

because it was around us all the time. So

17:46

we start noticing it, feeling

17:49

it, perceptually

17:52

reacting to it. And

17:54

if it's something good, the joy comes back. If

17:57

it's something bad, we feel the negative

17:59

feelings. again. Hmm.

18:02

So, you once got a clue on

18:04

how this habituation might work from a

18:06

story told by the movie star Julia

18:08

Roberts. Tell me that story. She

18:12

was describing her daily life, how

18:14

she wakes up in the morning

18:16

and she makes breakfast for the

18:18

kids. She drops them

18:20

off at school, she comes back home, she

18:23

maybe has lunch with her husband, she

18:25

does some chores and then she picks them up from

18:28

the school, makes dinner. And

18:30

she says, if I was here for the

18:33

last 18 years doing that all day, every

18:35

day, it probably wouldn't still have pixie dust

18:37

on it, but I go away and I

18:39

miss it so much and I come back

18:41

and it kind of re-sparkles. I

18:44

mean, that quote is great, but the word re-sparkles

18:46

is something that we really liked, right? How

18:48

do you just take the ordinary life and

18:50

make it re-sparkle? And what Julia is

18:52

saying is, well, every time

18:55

she goes away and then she

18:57

comes back, then she dis-habituates,

18:59

right? Because habituation is

19:02

something that happens when things

19:04

are always there, something constant,

19:06

something frequent. But if you

19:08

are not in that situation, if you go

19:10

away, then when you come back, then you

19:12

feel it again. And if it's good, then

19:14

it will re-sparkle. So

19:25

in some ways, the going away is

19:27

an essential component of the coming back

19:30

with joy. Yeah, indeed.

19:32

And in fact, after we

19:34

wrote the book and I

19:37

actually heard this podcast with Jodie

19:39

Foster, and she talks

19:41

about how she was away on set

19:44

filming for six months, and then she

19:46

got back home. And this

19:48

is what she said. She said, I came back from

19:50

somewhere that is amazing and beautiful, but you know you

19:53

long for really dumb things that you're just

19:55

used to. That six months ago, I'm sure

19:57

I was bored by it, but right now, I'm not going to do

20:00

I'm like, my God, avocados are amazing.

20:02

Or I'm so glad I get to

20:04

go to the gym again. Things

20:06

that six months ago were sort of what

20:08

I was trying to escape from. Now everything

20:11

is amazing. I mean, I

20:13

can tell you that when I go away

20:15

for a long time and I come back,

20:17

I just have this joy. You know, my

20:19

bed is like amazing. And then, you know,

20:21

the view from the window is amazing. Now

20:31

you might not be a Hollywood star who

20:33

goes away for months on end to shoot

20:35

movies in glamorous locations. That's

20:37

okay. You can get the ordinary

20:39

things in your life to re-sparkle, just by

20:41

getting up and going for a walk. Or

20:44

even wandering into the next room. So,

20:47

I mean, there's all levels of habituation, right? If I'm

20:50

now sitting in one room, I'm going to move to

20:52

the kitchen, what I see, what I smell is all

20:54

going to be different. It

20:56

means I'm going to have different information coming

20:58

into my brain, but also my brain will

21:00

be all set up for change. So,

21:04

it's been shown that if you

21:06

change your environment, even these small

21:08

changes, you sit in the office

21:10

and then you get up and you

21:12

just go for a walk or you work in a

21:14

coffee shop, any one

21:17

of those changes enhances your

21:19

creativity. Now, granted, the

21:21

studies show that the effects last

21:24

for about six minutes. Every time you change, it

21:26

lasts only for about six minutes on average, which

21:29

is small, but however, many

21:31

times that's all the amount that you need

21:33

to find that solution

21:35

that you are thinking of or that new

21:37

idea that is going to change what you're

21:39

doing. I

21:41

mean, I definitely have examples of that happening.

21:43

If I think I can really remember every

21:46

time that I had an idea that would

21:48

change the course of my research and would

21:50

be very important for what I do for

21:52

many years to come, and in

21:54

every single incident, I was not in

21:56

front of my computer working.

30:00

really puts this

30:02

in a great sentence, which

30:04

he says, pleasure results from

30:06

incomplete and intermittent satisfaction of

30:08

desires. So break

30:10

up the good experiences into bits

30:13

to enjoy it more. In

30:15

other words, when you order the chocolate cake at the

30:18

restaurant, you know, eat half a slice

30:20

because that's the slice that's actually gonna give you a

30:22

lot of pleasure, take the rest home

30:24

and eat it at home an hour later and

30:26

you'll enjoy the second half of the slice as

30:28

much as the first compared to eating it all

30:30

together in one go. Or even

30:32

better, give the second half to your partner. So

30:48

on the flip side, we often do try

30:50

to break up unpleasant experiences, so we don't

30:52

have to deal with all of it at

30:54

once. So, you know, we say, I need

30:57

to clean my bathroom, but maybe I'll do part of

30:59

it on a Saturday and part of it on a

31:01

Sunday. Is that a good idea or a

31:03

terrible idea? For the bad stuff,

31:05

you wanna, we say, swallow the bad whole. So

31:07

for example, if you think about something

31:10

that you don't like to do, maybe for

31:12

me, it's like household chores or grading papers.

31:16

If I do maybe like 15

31:19

minutes in a break, 20 minutes in a break, what

31:21

happens is that I'm breaking my habituation to

31:23

the bad. So if you're doing like cleaning,

31:25

for example, there's maybe like a bad smell

31:28

of the cleaning products, but you habituate to

31:30

it, so you don't smell it anymore. And

31:32

that's good, right? But if I then break it, I

31:34

have a little break and I have

31:36

a cup of coffee and then I go back and

31:39

I start the chore again, well, then I'm gonna feel,

31:41

again, bad, right? I'm gonna like perceive

31:44

the smell and all of that. And

31:47

again, there's empirical data when they actually did the

31:50

test with people listening

31:52

to really annoying sounds and

31:54

they found, yes, if you just get it

31:56

over with, you don't rate

31:58

it as bad. But if you kind of chop

32:01

it into bits, then you rate the experience as

32:03

much worse. It's

32:05

so interesting that our intuitions in both

32:07

cases are exactly the opposite of what

32:09

actually we should be doing. So we

32:11

have a reluctance to break up pleasant

32:14

experiences. We want to take them all in

32:16

at once. And we do want to break

32:18

up unpleasant experiences and not take

32:20

them in at once. And the advice

32:22

actually in both situations is to do

32:24

exactly the opposite. Yeah,

32:26

and you know, there are sayings about

32:28

savoring or about, oh, get it over

32:30

and done with. But then in reality,

32:32

it's really hard. It's hard to savor.

32:36

We, you know, if there's something good, we don't want

32:38

to stop. And it's

32:40

really hard when we're doing something unpleasant not

32:42

to take breaks. So

32:45

I think the wisdom is there in the

32:48

culture, but not necessarily something

32:50

that we do practically. Even

32:59

if the wisdom is difficult to follow, it

33:01

may seem straightforward. Power

33:03

through unpleasant tasks so you don't have

33:05

to experience the unpleasantness anew by coming

33:08

back to them multiple times. With

33:11

your pleasant experiences, do the

33:13

opposite. Break them up so that

33:15

you can maximize the delight they give you. Seems

33:18

simple, right? There's

33:20

a catch, though. Not all

33:23

unpleasant experiences are created

33:25

equal. And in some cases, there's

33:27

a very real cost that comes

33:30

from numbing ourselves to their unpleasantness.

33:35

When we come back, how our minds

33:37

habituate to things like danger, dishonesty

33:41

and discrimination. You're

33:44

listening to Hidden Brain. I'm Shankar

33:47

Vedanta. Support

33:58

for Hidden Brain comes from... foods market. It's

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are so many ways to save at Whole Foods

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Market. Now you know. This

34:33

is Hidden Brain. I'm Shankar Vedantam. Across

34:36

every domain of our lives, our

34:38

minds have a tendency to get accustomed to things.

34:41

In fact, the brain seems evolutionarily

34:44

designed to focus on the new

34:46

and unexpected on novel

34:48

threats and opportunities. In

34:51

our daily lives, this means we take wonderful

34:53

things for granted. We cease

34:55

to appreciate amazing people in our lives

34:57

or the good fortune of being healthy.

35:00

We become habituated to these gifts and

35:02

stop noticing them. With

35:05

Cass Sunstein, Tali Sharat is the co-author of

35:07

the book Look Again, the

35:09

power of noticing what was always there.

35:13

Tali, so far we've talked mostly about the ways

35:15

we habituate to positive things, but

35:17

of course the mind also habituates

35:19

to negative things. In

35:21

1999, a huge public works project in Massachusetts

35:24

was wrapping up. It had taken a decade

35:26

to complete. All that remained

35:28

was to open an underwater tunnel. I

35:31

want to play you a public television news clip about

35:33

what happened that day. The

35:36

tunnel burrowed into the bay's bedrock

35:38

was devoid of light and oxygen,

35:41

requiring the divers to carry a

35:43

specialized breathing system. On

35:46

a July morning, the five divers

35:48

set out. Disaster struck when the

35:50

breathing system malfunctioned. Three

35:52

of the divers made it out alive,

35:55

but two died. 33 year

35:57

old William Juice and 39 year old Tim

36:00

Nordine died of asphyxiation. Tali,

36:04

tell me the story of this project and

36:06

what it tells us about habituation. So

36:09

there was a decade-long Boston

36:11

Harbor cleanup. So if you visit Boston

36:14

today, there's clear blue waters, there's sailing

36:16

boats all around. But back in the

36:18

day, apparently, it was quite dirty. It

36:21

wasn't as nice. And so they had

36:23

hundreds of workers working. It cost $4

36:25

billion to clean up the harbor. And

36:28

it was high risk. At

36:31

the very end, they sent five divers

36:33

into a tube hundreds of feet below

36:35

the ocean floor to remove heavy safety

36:38

plugs. And the

36:40

tunnel had no oxygen or light. And

36:42

the narrowest part of it was only

36:44

five feet in diameter. And

36:46

the divers were to travel all the way

36:48

to the far end of the 10-mile-long tunnel.

36:50

And then inside a series of pipes, there

36:52

were only about 30 inches wide. So they

36:54

became kind of smaller and smaller. And

36:57

despite the project was pretty complex, the

36:59

drivers trained for it for only two

37:02

weeks. And they

37:04

relied on experimental breathing apparatus. So

37:06

it doesn't seem that a lot

37:08

of cautionary measures were taken. And

37:11

unfortunately, the breathing system failed. And only

37:13

three of the five divers got back

37:16

to safety. And even

37:18

those that got back to safety had only

37:20

30 seconds to spare. And

37:23

so it actually is not

37:25

unusual that disasters in,

37:27

for example, these kind of construction projects,

37:29

they tend to happen very

37:31

late in the project, towards the very end. Because

37:34

what seems to happen is that

37:37

early on, people are very cautious,

37:39

they're very risk averse. They take

37:42

all the measures. But then

37:44

after time, they habituate to

37:47

the risk. They don't have

37:49

the emotional reaction, the anxiety and the fear.

37:52

And that's when most of the

37:54

accidents on construction sites tend to

37:57

happen. So,

40:08

we've looked at the role of habituation when

40:10

it comes to risk, but that's not the

40:12

only domain in which we can see habituation

40:14

when it comes to negative things.

40:16

You've also looked at habituation when

40:19

it comes to dishonesty. Can

40:21

you tell me how you've designed those studies? What is the

40:23

setup of those studies? We

40:26

were interested in whether

40:28

people habituate to their own

40:31

lying. Most people think that

40:33

lying is immoral, right? But if

40:36

your emotional response will go

40:38

down over time, the more you lie, then

40:40

you'd probably lie more and more and more.

40:43

And this is exactly what we tested. So

40:46

we had people come into the lab

40:48

and we asked them to play a

40:50

game. And in this game, they realized

40:52

that if they lied to the other

40:54

person, they could gain more money at

40:56

the expense of the other person. And

41:00

we also recorded their brain activity. And

41:02

what we found that at the beginning, they liked but just

41:04

a little bit, maybe a few cents. Next

41:07

time they had an opportunity, maybe a few

41:09

dollars, and the amount by which they lied

41:11

became bigger and bigger, right? It's like the

41:13

slippery slope. And

41:15

at the same time, we looked at activity

41:17

in their amygdala. So the amygdala is a

41:20

small part of the brain and it is

41:22

important for emotional arousal. And

41:24

what we found is at the beginning when

41:26

people lied, there was a strong emotional response,

41:28

right? They felt bad about lying. The

41:31

next time they lied, less of an emotional

41:33

response. The third time they lied, less. And

41:36

as the amygdala activity went down indicating

41:39

less emotional arousal, people lied more and

41:41

more and more.

41:45

That study looks at how we habituate to our

41:47

own lying, but you also habituate to the lies

41:49

of other people. If

41:53

you are in an environment, let's say a

41:55

work environment where people are lying, but they

41:57

start with small lies. Maybe

42:00

they lie a little bit about their expenses, you

42:02

know, maybe they lie a little bit to the

42:04

client about what the product can do. And

42:08

then they lie more and more and more

42:10

that they start really taking in, you know,

42:12

thousands of dollars that they shouldn't. You

42:15

are more likely to just accept and

42:18

maybe not even notice if the lies are

42:20

gradual. And we see

42:22

this in reality when people

42:25

who have been quite

42:27

dishonest, Bernie Madoff, for

42:29

example, they actually tell you about

42:31

how they started out with small lies and became bigger

42:33

and bigger. There's a wonderful quote by

42:36

him. He says, it start out with you

42:38

taking a little bit, maybe a few hundred,

42:40

a few thousand, you get comfortable with that.

42:42

And before you know it, it snowballs into

42:44

something big. And what I

42:46

like about this quote is that he says, you get

42:48

comfortable with that. What this tells

42:50

me is that he probably felt bad about

42:52

it when he began. But

42:55

over time, habituation, he

42:57

became comfortable. Then he can lie

42:59

more and more. So

43:02

along the same lines, Tali, I'm guessing

43:04

we can also habituate to other problematic

43:06

things, things like misinformation

43:08

or pollution or corruption. You

43:10

know, if these are things that are all around

43:12

us all the time, after some time it becomes

43:15

hard to muster a sense of outrage. Yeah,

43:18

absolutely. With misinformation,

43:20

actually, there's surveys showing that

43:24

they ask people, do you think it's

43:27

okay to kind of fudge a story

43:30

in order to get more clicks? And

43:32

the percentage of people who said it was okay was

43:35

much smaller about 15 years ago

43:37

than it is today. So

43:41

I think with all this kind of like

43:43

fake news and misinformation online, social media, we

43:45

started becoming just used to this.

43:48

We're not as outraged when we learn

43:50

that someone is changing the story a

43:52

little bit or maybe just making it

43:54

up completely. It

43:56

seems that we accept it. We don't have much of

43:59

an emotional response. we don't notice it

44:01

as much. So, you

44:04

know, we've looked at sort of many examples

44:06

of habituation here when it comes to risk,

44:08

to, you know, misinformation,

44:10

to dishonesty. But

44:12

at a grand level, I'm also wondering whether

44:14

it works at the level of society. When

44:16

you look at the rise of authoritarian states,

44:19

for example, you know, sometimes they take

44:21

away the rights of minorities, but they don't do everything

44:23

on day one. On day one, it's just a little

44:25

bit. On day 10, it's a little more. And

44:27

then by day 500, you know, they've taken

44:30

away a lot, but by that point, people

44:32

have become desensitized through the same process of

44:34

habituation. Right. And I think

44:36

when we look back at

44:39

the history of humanity, there are all these

44:41

dark stories of oppression and bloody wars and

44:43

genocide. And we often look back and we

44:45

said, how could that be? Right? Why

44:48

wasn't that stopped earlier? And

44:50

I think part of the answer is

44:52

that these extreme political movements and deadly

44:54

conflicts, they start small and then they

44:57

crease gradually. And

44:59

because they increase very gradually, they

45:01

end up eliciting a weaker emotional

45:03

reaction. And because there's

45:05

less emotional reaction, there's less resistance, right?

45:08

And more acceptance than there would otherwise

45:10

be. And we

45:12

talk about this in our

45:14

book and we take Nazi Germany as

45:16

an example. And

45:18

there's a lot of testimonies of,

45:21

for example, German citizens that explain

45:23

what happened. And when you kind

45:25

of read those testimonies, they often

45:27

talk about how things really

45:30

escalated slowly. Right.

45:33

People say that each act and each

45:35

occasion was worse than the last, but only by

45:37

a little bit. Right. So

45:40

we started, started by Jews are not allowed to be

45:42

doctors, not allowed to be journalists, and books are burned.

45:45

And then, you know, there are hundreds

45:47

and hundreds of steps. And the last

45:49

one is mass

45:51

murder is genocide. Right. The

45:54

last act was a first act that

45:56

would, I believe, would have

45:59

resulted in much more of a

46:01

reaction from the people, but

46:04

it's not. And there's this

46:06

quote from a German citizen

46:08

that he says, that people could not see

46:10

it developing from day to

46:12

day like a farmer in the

46:14

field that doesn't see the corn growing. It

46:17

grows slowly, slowly, and then one day it's

46:19

over your bed. There

46:30

are many other scenarios in which our tendency to

46:33

habituate to bad things can

46:35

bring terrible consequences. One

46:37

example, climate change. Many

46:40

of the warning signs of climate change are

46:42

subtle and easy to miss. But

46:45

even when they are stark and

46:47

dramatic, think of melting ice caps

46:49

or raging wildfires or dramatic flooding,

46:52

our minds habituate to these phenomena. They

46:55

become expected, normalized.

47:00

The problem here is that, first of

47:02

all, perceptually we habituate. When

47:05

things, let's say pollution, if there's pollution in

47:07

the air constantly, you kind of get used

47:09

to it and we don't really notice it's

47:12

in the air. There's a really interesting survey

47:14

that shows that in the UK, only 10%

47:17

of people rate their air quality as poor,

47:19

despite the fact that pollution reaches legal limits

47:21

in 88% of UK regions. And

47:26

then there's also just kind of more

47:28

of accepting of this idea. Over

47:31

time, we accept the idea that

47:33

there's climate change and that

47:35

there are going to be hurricanes or things like that, and

47:37

so we have less of a reaction to it. And

47:40

in fact, that's also been shown nicely on

47:42

Twitter. So there's a study where they

47:45

looked at people, what they

47:47

said about extreme climate

47:49

events on Twitter. What

47:51

they found is that extreme climate events,

47:54

like hurricanes, for example,

47:58

as they became more and more frequent, people

48:00

stopped tweeting about it. And

48:02

on average, it took between two to eight

48:04

years for people to stop

48:07

tweeting about climate events, like extreme

48:09

temperature. And if you don't see

48:11

it and you don't talk about it, then you don't act. So

48:15

what is the solution for this, Tali? I

48:18

understand how habituation can work with climate change, but

48:20

is there a way to fight it? Well,

48:23

I think the solution here is

48:25

not to rely on our perception, to

48:29

rely on instruments, right? The

48:31

instruments can tell us quite well what

48:34

is happening with the temperature, with

48:36

climate events, and we

48:38

need to rely on the data, not

48:40

on our feelings or how we perceive

48:42

the world to be. It's just not

48:44

reliable. Because of

48:46

course, I think what you're pointing out is that our

48:49

perceptions might habituate to climate change, but

48:51

our instruments will not, and they will

48:54

continue to tell us the story. And

48:57

if we can't trust our own intuitions, what

48:59

we can trust is the data coming in

49:01

from our instruments. Right,

49:04

but you know, it's really hard for people to

49:06

do that. It's really hard for us to say,

49:08

I'm gonna ignore my perception, I'm gonna rely

49:10

on the instrument. This

49:13

is a well-known problem. Often,

49:16

pilots are flying, and

49:18

they can go into vertigo, and

49:20

they feel like they're flying up towards, up

49:22

in the air, when in fact, they're flying

49:24

down towards the ground. And the instruments show

49:27

them, you're flying down towards the ground, but

49:29

they feel like they're flying up. And it's

49:31

really hard to just

49:33

say, okay, I'm gonna go with the instrument, right? I'm

49:36

gonna fly my plane into what I believe

49:38

is into the ground, because

49:40

the instrument is telling me, no, this is the way you

49:43

should do it. And that can lead to accidents, and it

49:45

has led to accidents. I

49:48

mean, so much of the story is about how our

49:50

brains have this propensity to forget

49:52

and ignore, and eventually not

49:54

notice something, and how in some ways this

49:56

can be functional in some elements of

49:59

our lives. But in other situations, it really

50:01

is helpful to be able to slow down, to be

50:03

able to see again. There's not

50:05

sort of a one-size-fits-all rule when it

50:07

comes to habituation and disabituation, is there?

50:10

Yeah. I mean, on one hand, we all

50:12

want to kind of have that joy

50:15

again of the things that have been around us for

50:17

a long time. And we can remember in the past

50:19

how much joy they had triggered in

50:21

us, but now we have habituated. So,

50:23

you know, we want to do these things that can maybe

50:26

cause us to feel more of the happiness

50:28

and the joy, but also

50:31

to be able to see things

50:33

around us, like cracks in our

50:35

relationships, inefficiencies at work, but also

50:37

the bigger things, racism and sexism,

50:40

so we can act to change

50:42

them. Tali

50:53

Sharat is a cognitive neuroscientist at

50:56

University College London. Along

50:58

with Cass Sunstein, she's the author of Look

51:00

Again, The Power of Noticing What

51:02

Was Always There. Tali, thank

51:04

you for joining me today on Hidden Brain. Thank

51:07

you so much for having me. It was a pleasure. Hidden

51:17

Brain is produced by Hidden Brain Media. Our

51:20

audio production team includes Annie

51:22

Murphy-Paul, Kristen Wong, Laura Quirell,

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Ryan Katz, Autumn Barnes, Andrew

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Chadwick, and Nick Woodbury. Tara

51:29

Boyle is our executive producer. I'm

51:32

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