Hidden Brain - Making the World Sparkle Again

Episode Date: June 24, 2024

Across every domain of our lives, our minds have a tendency to get accustomed to things. In fact, the brain seems evolutionarily designed to focus on the new and unexpected, on novel threats and opportunities. In our daily lives, this means we take wonderful things for granted. We cease to appreciate amazing people, or the good fortune of being healthy. This week, neuroscientist Tali Sharot explains why we get used to things — and how to see with fresh eyes.Our podcast subscription, Hidden Brain+, is now available across platforms and devices. You can sign up for a free seven-day trial at support.hiddenbrain.org or apple.co/hiddenbrain. Your subscription provides key support to help us build you many more episodes of Hidden Brain. We’re truly grateful. 

This is Hidden Brain. I'm Shankar Vedantam. In March 2020, a few weeks after COVID-19 lockdowns began in the US, we asked listeners to send us voice memos about their experiences of the pandemic. We recently went back and listened to those messages, each one a tiny time capsule of life in a world under lockdown. Listeners told us about the stress of trying to find toilet paper and masks. They talked about the challenge of trying to work over Zoom. And more than anything, they grappled with the sudden, shocking ways in which their lives

had become smaller and more isolated. I don't know if I could live with myself if I was stuck here and something were to happen to my grandma. And this is especially apparent when I found out that I could not visit my father in his independent living facility. My older sister gave birth to her son. We weren't able to be with her at the hospital, nor have we been able to see him. In those early days of the pandemic, so many of us found ourselves dreaming about what it would be like

when we could once again hug friends and family outside our immediate household. We fantasized about the moment when we could enjoy going out to a restaurant or a music venue. We told ourselves that we would not take those moments for granted once we had them back. And indeed, the first time I got to see relatives overseas and enjoy dinner out with friends, it was truly amazing. The second time was pretty great as well. But after a while, that magical feeling inevitably started to fade, no matter how hard I tried

to hold on to it. We see this in many dimensions of our lives. So many love stories end at the point at which great romantic quests are consummated. Stories that follow lovers past the wedding day into the years and decades of their marriages, those tend not to be romantic comedies. It's easy to be cynical and say that nothing lasts,

that everything fades away. But this belies what actually happens in our minds as we experience triumphs and setbacks. This week on Hidden Brain, the psychology of habituation. How we get used to both the good and the bad in our lives, and the surprising implications it has for happiness. Think about the last time you saw one of your favorite desserts on a menu. Maybe it's the restaurant's signature chocolate cake. Your mouth waters as you read the description and you order a menu. Maybe it's the restaurant's signature chocolate cake. Your mouth waters as you read the description and you order a slice,

gleefully anticipating how good it will taste. The first bite does not disappoint. It's out of this world. As you continue to dig in, however, something funny happens. The cake no longer blows your mind. You lift your fork to your mouth a few more times, trying to recapture the magic of that first bite. But it's no use. What had been unbelievably delicious minutes earlier is now merely pleasant.

What explains this? More importantly, what can we do to make the second half of that slice of cake taste as good as the first? These are questions that animate cognitive neuroscientist Tali Sharit at University College, London. Tali Sharit, welcome back to Hidden Brain. Thank you.

It's a pleasure to be back. Tali, you did some research in a resort in the Dominican Republic. Can you describe the setting for me and what questions you asked the people who were vacationing there? Yeah, so I was working with a big tourism company, and what they wanted to know is what makes people happy on vacation and when are they the happiest on vacation. So we did surveys and we actually went out to the resorts

and we talked to people, And when the data came in, we found two really interesting things. The first was that the holiday makers were the happiest 43 hours in. Why is that? Well, 43 hours allowed them time to get settled and unpacked so they could really concentrate on fun. But after that, happiness starts going down, right?

Less and less joy. Now, to be clear, they were always happy, happiness starts going down, right? Less and less joy. Now, to be clear, they were always happy. But on day eight, they weren't as happy as they were on day seven. Day seven, not as happy as day six, and so on and so forth. And the second thing that we found is that when we asked them what was the best part of the holiday, there was one word that they used more than any other word. and that word was first. The first view of the ocean, the first cocktail, the first sandcastle, the first dip in the pool.

Firsts were exciting and new. The second dip in the pool was also good, but it wasn't as good as the first. And this is really, I think, a great example of habituation, right? When you see the ocean, it's wonderful. And the second time you see it, it's still wonderful, but it's not quite as wonderful as the first time. Things that are around us all the time, that are constant or that are frequent,

we just respond less emotionally, and even perceptually, we respond to them less. So psychologists have found the same phenomenon happening not just among people eating dessert or going on vacation, but in relation to the most significant events of life, like getting married. What does the research show about happiness levels among newlyweds? Happiness actually goes up when people get married, on average, but then it starts going down and down and down and it reaches baseline level,

that is the level that before they got married, at about, in about two years. And also attraction to their partner goes down over the years. I mean, this is why so many Hollywood movies to their partner goes down over the years. I mean, this is why so many Hollywood movies end with the wedding or even the first kiss. Yes, yes, absolutely. But as we habituate, meaning we respond less

to things like to the view of the ocean, we also respond less to our new love, right? What is around us constantly just doesn't really gather our attention as much, right? And we kind of, we don't attend to it, and so we don't really focus on it as much, and it doesn't really spark that kind of joy and excitement than it did at the beginning.

So as I was reviewing this work, I could think of all kinds of things in my own life where I feel I have habituated to things. The same must be true for you, Tali. Can you tell me about some things that you have habituated to? Yeah, absolutely. Probably to almost everything, I would say.

You know, even my work, right? I mean, if you think about when you first got your first job entry-level position, it is really exciting and new, right? I mean, if you think about when you first got your first job entry level position, it is really exciting and new, right? But after a while, you kind of get used to it. And even if the job is your dream job, and it's really meaningful work, over the years, it doesn't seem that interesting. it doesn't seem that exciting. Tali experienced this acutely after buying the house she lives in. We moved into this house in the middle of the pandemic.

So we have two kids and we were living in the city, in a place that was a little bit too small, I think for a family of four. But it was fine before the pandemic because we weren't in the home at all times. But of course then the pandemic started and so all of us are at home at all times. The kids are studying at home and so we moved to a much more spacious place outside of the city. And when I first moved, it felt just the perfect place to be. And it really brought me a lot of joy. Everyone had a room for themselves and also had a garden and there was trees and greenery. So

you look out of the big windows and you see all this green which makes you feel happy. And it still does but of course I got used to it and so the reaction is less and less and less. So we've talked about this phenomenon on hidden brain before. Psychologists sometimes call this the hedonic treadmill. For listeners who are unfamiliar with the term, can you explain what that is and also the links to this larger phenomenon you've been talking about called habituation? Yeah, so the hedonic treadmill is this idea that people have a baseline of happiness and you know some people could be a little bit happier than others.

We can go do something that makes us happy, get married, get a nice job, but eventually we will kind of slowly, slowly go back to this baseline. Also, bad things happen to us. It could be really bad things. Lose a loved one, lose your job, and we would, of course course feel much worse when these things happen. But then eventually, slowly, slowly, slowly, we go back to our baseline. So that's basically the hedonic treadmill. But I think the phenomena that we're talking about, habituation, is it's related, right? But it's not quite the same. It is much, much broader.

Habituation means that we just respond to anything that is around us, anything visual or smell. So for example, you go into a room and you really smell, let's say roses, right? Within about 20 minutes, you won't be able to perceive the smell of roses because your olfactory neurons will just not respond anymore. Or you hear the noise of the AC in the background and

it could be quite irritating at first, but very quickly you just don't notice it anymore. Right? So all these are perceptual examples, but our emotional reactions to things. It could be a dog barking. It's like the neighbor got a new dog and it's really scary, and we have a fear reaction, but the second time, less so, and the third time, less so. So there's perceptual habituation,

there's emotional habituation, and it has a lot of implications beyond the hedonic treadmill to our personal life, but also to society. So why does this happen, Tali? Why is it that the brain habituates to things? At a fundamental level, it seems like it's a property of the brain. Why does this happen?

Right. So there is an evolutionary advantage, right? The brain has limited resources, and so once we've processed something, then it's really time for the brain to keep the resources for the next thing that is coming our way. So imagine there's a dog and the dog is in the rose garden and the smell of roses really fills its nostrils. It is helpful that after a while, the olfactory neurons will just stop responding. So now we have all the resources needed for the dog

to be able to smell a coyote that is coming its way. So we need to be prepared for these threats that are coming our way. So we need the resources, but also for the good things. Maybe there's a cookie somewhere in the distance that the dog should go and get. So that has an evolutionary advantage, but it also keeps us motivated.

So if you think back to your entry-level job and you were super happy about it, imagine you stayed super happy forever. You will not be motivated to get to the next promotion, to get to the next job. You'll just stay where you are. So we need habituation in order to evolve as a person, but also as a society. And maybe

the third important factor is well-being and mental health. So what has been shown is that people with mental health problems, for example, depression, tend to habituate slower. People with depression, when negative things happen, they don't bounce back as fast. There's a great study that was conducted by Professor Aaron Heller from the University of Miami where he asked students who just got a score on a really important test how they were feeling, and then 45 minutes later he asked them how they were feeling, and 45 minutes later how they were feeling, and did that for the rest of the day and the next day. And what he found is that those without a history of depression and those with history

of depression, they all felt really bad at the beginning if they got a bad grade. But the difference was that those that did not have a history of depression, they after a few hours, they were back at baseline, right? They were doing their things, going out. But those with a history of depression or current depression, they tend to ruminate. They weren't able to go back to just their level of well-being that they were before, right? They were kind of stuck and habituated much, much slower. You say that in order to survive and reproduce,

we need to prioritize what is new and different. So the sudden smell of smoke or a rustle in the bushes that could signal a lion or a predator, an attractive potential mate who passes by. You say to make the new and the unexpected stand out, your brain filters out the old and expected. So in some ways, this is really a fundamental property of the brain that's really been designed

through millions of years of evolution. Yes, and habituation is something that we could see in all animals, whether it is a rodent or a dog or a fish. And in fact, we can see something very similar, what we call neural adaptation, in even bacteria. So this is something that goes way, way, way back and is really fundamental. I mean every neuron in our brain habituates. Our brains painstakingly construct models of what the world is like. When reality conforms

to that model, we don't react, or even notice it very much. When we come back, how to step off the hedonic treadmill and feel the goodness of good things again. Also, we'll explore the flip side of the hedonic treadmill, the way we habituate to things again. Also, we'll explore the flip side of the hedonic treadmill, the way we habituate to things that are scary, shady, and sad. You're listening to Hidden Brain. I'm Shankar Vedantam. Tali Sharath is a cognitive neuroscientist at University College London. With Cass Sunstein, she's the author of Look Again, the power of noticing what was always there.

Tali, you've told us how the process of habituation can diminish the pleasure and satisfaction that an event or an experience might once have given us. You say that there's a solution to this that you call dishabituation. What do you mean by the term? So dishabituation means starting to respond again to something that we stopped responding because it was around us all the time. So we start noticing it, feeling it, perceptually reacting to it, and if it's something good, the joy comes back.

If it's something bad, we feel the negative feelings again. Hmm. So, you once got a clue on how this habituation might work from a story told by the movie star Julia Roberts. Tell me that story. She was describing her daily life. How she wakes up in the morning and she makes breakfast for the kids. She drops them off at school.

She comes back home. She maybe has lunch with her husband. She does some chores and then she picks them up from the school, makes dinner. And she says, if I was here for the last 18 years doing that all day, every day, it probably wouldn't still have pixie dust on it. But I go away and I miss it so much and I come back and it kind of sparkles. I mean that quote is great but the word sparkles is something that we really liked right? How do you just take the ordinary life and make it a sparkle? And what

Julia is saying is well every time she goes away and then she comes back then she dishabituates right because habituation is something that happens when things are always there something constant something frequent but if you are not in that situation if you go away then when you come back then you feel it again and if it's good then it will respond to. So in some ways, the going away is an essential component of the coming back with joy. Yeah, indeed. And in fact, after we wrote the book, and you know,, I actually heard this podcast with Jodie Foster and she talks about how she was away on set filming for six months and then she got back home. And this is what she said, she said, I came back from somewhere that is amazing and beautiful, but you know, you long

for really dumb things that you're just used to that six months ago, I'm sure I was bored by it, but right now I'm like, my God, avocados are amazing, or I'm so glad I get to go to the gym again. Things that six months ago were sort of what I was trying to escape from. Now everything is amazing. I mean, I can tell you that when I go away for a long time and I come back, I just have this joy.

My bed is like amazing. And then, you know, the view from the window is amazing. ["The Star-Spangled Banner"] Now you might not be a Hollywood star who goes away for months on end to shoot movies in glamorous locations. That's okay. You can get the ordinary things in your life

to re-sparkle just by getting up and going for a walk, or even wandering into the next room. So, I mean, there's all levels of habituation, right? If I'm now sitting in one room, I'm going to move to the kitchen, what I see, what I smell is all going to be different. It means I'm going to have different information coming into my brain, but also my brain will be all set up for change. So it's been shown that if you change your environment, even these small changes, you sit in the office and then you get up and you just go for a walk or you work in a coffee

shop, any one of those changes enhances your creativity. Now granted, the studies show that the effect lasts for about six minutes. Every time you change, it lasts only for about six minutes on average, which is small. But however, many times that's all the amount that you need to find that the solution that you are thinking of or that new idea that is going to change, you know, what you're doing. I mean, I definitely have examples of that happening. If I think I can really remember every time that I had an idea that would change the course of my research and would be very important for what I do for many years to come. And in every single incident, I was not in front of my computer working.

Right. So, one example is I was not in front of my computer working. Right. So one example is, um, I was in my office, I was trying to solve this problem. We had this data and we couldn't make sense of it. Why is it happening? Couldn't solve it. And I said, okay, I'm going to go to the gym, left the office, started walking towards the gym. I didn't even get to the gym. And, and I, the solution just came to me.

Um, another example is, um, I was again in my office working, but then I decided to have a little break. And I opened up the New York Times science section and I read about a study in monkeys, about how monkeys really enjoy getting information. Even if the information they can't use for any reason altogether, they really like it. And the dopamine neurons, dopamine is important for our reward system, they are activated when the monkey gets information. And the monkeys like it so much, they're even willing to give up some of their water in order to get more information. And so I thought that was really interesting. and that will eventually trigger research that I did on humans on the value of information.

We know that some pleasures lose their sparkle very quickly. We've all been excited about some new purchase only to see it gather dust in a corner before too long. But you say there are some experiences that retain the capacity to generate happiness over time. Explain the difference and what do you think is going on? So material goods, you can buy something and you can use it for years, right? Maybe it's a piece of clothing, maybe it's a TV, but probably

the joy that you get will just go down over time. Now here's the interesting thing when it comes to experiences. Maybe you went on vacation to Thailand, maybe you went to a concert, right? You saw Amy Winehouse before she died. And the reason that they tend to habituate slower is because they stay in your mind, right? So they come up in your mind when you recollect them, rather than kind of processing them in front of us. And so this was actually shown in a study that the rate of habituation for material goods is faster than the rate of habituation for experiences. So we're also slower to habituate to the pleasures of giving compared to the pleasures of receiving. Can you talk about this idea, Tali?

Yeah, so there was a study that was conducted where in one condition they gave people five dollars and they said, take the $5 and buy whatever you want for yourself. You could buy a coffee, you could buy a pen. Day number two, $5. Buy whatever you like. Day number three, $5. And they did that for a few days.

And every time they asked the people, well, how much did you enjoy whatever you got with those $5? In another condition, they gave people again $5, but this time they said, buy something for someone else. So this time you're buying coffee for your colleague or you're buying a pen for your child, right? And every day they give them $5 and they would buy something for someone else and they ask them, how much did you enjoy this? How much, you know, how good did it make you feel? Now what's interesting in this study is they looked at the rates of habituation, right? In both cases, the $5 will give you less joy over the days,

but the rate of habituation was much faster when you got things for yourself than when you got it for someone else. And I think perhaps the reason is that the joy that you get from giving is not just pure happiness. it is meaning as well. There's a meaningful act in giving to someone else. And while the feeling of meaning can also habituate, it probably habituates slower

than just pure joy of drinking the coffee or using your sparkly pen. You said that another way we can thwart habituation is by seeking out opportunities to learn. Talk about this idea, how is curiosity and learning, how can they be engines or defenses against habituation? So when you ask people, what is a good life? What do you see as a good life? Usually people will say, I want to feel joy, right?

I don't want to feel sad. And they usually say, what I want meaning in my life. And then there's a third thing that tends to be an element of a good life, which people don't usually think about so much, which is variety. It turns out that variety is something that enhances people's psychological experiences, right? It gives you like a rich psychological experience and why is that helpful? And there's a few answers to this.

One is that variety means that we will habituate less to things because it's changing all the time, right? We're doing one thing, we're doing the other thing, right? So variety actually counters the effects of habituation. But the other reason is if you have variety in your life, you work on different projects, you talk to different types of people, you are in different places. It always involves learning.

And the thing about learning is, learning means that there is a change. You cannot habituate to change, by definition. Gaining knowledge is processed in the brain like food, like water, like sex. There's the response that we have when we are learning something new, which, you know, why do people enjoy podcasts so much, right? Because you're always learning, you're gaining knowledge, and your brain responds to that like it does to chocolate, but you don't get fat.

So let's go back to the example of eating dessert or going on a vacation. Many of us assume that when it comes to pleasant or joyful experiences, it's best to enjoy these experiences without interruption. But from what you're saying in the last few minutes, I'm not sure that's true. Is it, Telly? Yeah, no, it's not. Because let's go back to the vacation example. The most, like happiest time was 43 hours in.

And the word that they use most to describe the best parts of the vacation was first, first, first, first. So then really what that means is that you want to create more firsts. You want to create more 43 hours in, right? So instead of going for a long two-week vacation somewhere, you might choose to go on shorter, maybe like a long weekend or, you know, maybe just a weekend. So take a few short vacations rather than the long one to get more of these exciting novel things. And there's empirical evidence to support this. So there is a great study where people

were asked, think about a song that you really like and What do you think would you enjoy it more if you listen to the song from beginning to end with no interruptions? Or if you had interruptions, so you listen to the song 20 seconds and a little interruption 20 seconds little interruption 99% of people said I want to hear the song from beginning to end. I do not want any interruptions, right? I mean, it seems obvious. But when they then did the test and they tested how much people enjoy the song with or without interruptions,

what they find is that people enjoy the song more if it was interrupted. And they were willing to pay twice as much to hear the song in concert, which is super counterintuitive. And they did the same study with massages. Do you want to have the massage from beginning to end, no interruptions? Or do you want to have it with breaks? People want it beginning to end, no interruptions, but in fact, enjoy it more if there are breaks. And there is an economist

named Tipper Skutovsky who has a quote which really puts this in a great sentence, which he says, pleasure results from incomplete and intermittent satisfaction of desires. So break up the good experiences into bits to enjoy it more. In other words, when you order the chocolate cake at the restaurant, eat half a slice because that's the slice that's actually going to give you a lot of pleasure. Take the rest home and eat it at home an hour later and you'll enjoy the second half of the slice as much as the first compared to eating it all together in one go. Or even better, give the second side, we often do try to break up unpleasant experiences, so we don't have

to deal with all of it at once. So we say, I need to clean my bathroom, but maybe I'll do part of it on a Saturday and part of it on a Sunday. Is that a good idea or a terrible idea? For the bad stuff, you want to, we say, swallow the bad hole. So, for example, if you think about something that you don't like to do, maybe for me, it's like household chores or grading papers.

If I do maybe, like, 15 minutes in a break, 20 minutes in a break, what happens is that I'm breaking my habituation to the bat. So if you're doing like cleaning, for example, there's maybe like a bad smell of the cleaning products, but you habituate to it so you don't smell it anymore. And that's good. But if I then break it, I have a little break and I have a cup of coffee and then I go back and I start the chore again,

well then I'm gonna feel, again, bad, right? I'm gonna like perceive the smell and all of that. And again, there's empirical data when they actually did the test with people listening to really annoying sounds and they found, yes, if you just get it over with, you don't rate it as bad, but if you kind of chop it into bits,

then you rate the experience as much worse. It's so interesting that our intuitions in both cases are exactly the opposite of what actually we should be doing. So we have a reluctance to break up pleasant experiences. We want to take them all in at once, and we do want to break up unpleasant experiences and not take them in at once.

The advice actually in both situations is to do exactly the opposite. Yeah. You know, there are sayings about savoring or about like, oh, get it over and done with. But then in reality, it's really hard. It's hard to savor. If there's something good, we don't want to stop. It's really hard when we're doing something unpleasant not to take breaks. So I think the wisdom is there in the culture, but not necessarily something that we do practically. Even if the wisdom is difficult to follow, it may seem straightforward.

Power through unpleasant tasks so you don't have to experience the unpleasantness anew by coming back to them multiple times. With your pleasant experiences, do the opposite. Break them up so that you can maximize the delight they give you. Seems simple, right? There's a catch, though. Not all unpleasant experiences are created equal. And in some cases, there's a very real cost

that comes from numbing ourselves to their unpleasantness. When we come back, how our minds habituate to things like danger, dishonesty, and discrimination. You're listening to Hidden Brain. I'm Shankar Vedantam. This is Hidden Brain. I'm Shankar Vedantam. Across every domain of our lives, our minds have a tendency to get accustomed to things. In fact, the brain seems evolutionarily designed to focus on the new and unexpected, on novel threats and opportunities. In our daily lives, this means we take wonderful things for granted. We cease to appreciate amazing people in our lives or

the good fortune of being healthy. We become habituated to these gifts and stop noticing them. With Cass Sunstein, Tali Sharit is the co-author of the book, Look Again, The Power of Noticing What Was Always There. Tali, so far we've talked mostly about the ways we habituate to positive things, but of course the mind also habituates to negative things. In 1999, a huge public works project in Massachusetts was wrapping up. It had taken a decade to complete. All that remained was to open an underwater tunnel. I want to play you a public television news clip about what happened that day.

The tunnel burrowed into the bay's bedrock was devoid of light and oxygen, requiring the divers to carry a specialized breathing system. On a July morning, the five divers set out. Disaster struck when the breathing system malfunctioned. Three of the divers made it out alive, but two died. Thirty-three-year-old William Juice and 39-year-old Tim Nordean died of asphyxiation. Tali, tell me the story of this project and what it tells us about habituation. So there was a decade long Boston Harbor cleanup.

So if you visit Boston today, there's clear blue waters, there's sailing boats around. But back in the day, apparently, it was quite dirty. It wasn't as nice. And so they had hundreds of workers working. It costs $4 billion to clean up the harbor. And it was high risk the whole time. But at the very end, they sent five divers into a tube hundreds of feet below the ocean floor to remove heavy safety plugs.

And the tunnel had no oxygen or light. And the narrowest part of it was only five feet in diameter. And the divers were to travel all the way to the far end of the 10-mile long tunnel. And then inside a series of pipes, there were only about 30 inches wide, so they became kind of smaller and smaller. And despite the project was pretty complex, the drivers trained for only two weeks and they relied on experimental breathing apparatus, right? So it doesn't seem that a lot of cautionary measures were taken. And unfortunately, the breathing system failed and only three of the five divers got back

to safety. And even those that got back to safety had only 30 seconds to spare. And so it actually is not unusual that disasters in, for example, these kind of construction projects, they tend to happen very late in the project, towards the very end. Because what seems to happen is that early on, people are very cautious, they're very risk averse, they take all the measures.

But then after time, they habituate to the risk. They don't have the emotional reaction, the anxiety and the fear. And that's when most of the accidents on construction sites tend to happen. So you've conducted research that examines the process of risk habituation using virtual reality. Tell me the setup of these studies, Tali. Right, so we wanted to put people in a really threatening position, something that really will kind of cause them fear. But of course, we can't put our participants in a place where they're really under physical risk. So we use the next best thing, which is virtual

reality. And we use this game in virtual reality where what you see is yourself going up an elevator, up a skyscraper, and then the elevator opens up and then you can walk on a plank that is basically far, far, far up, up, up, up, up, and you're looking down and it's really scary. Now, it absolutely tricks your brain to believe that I'm thousands of feet up walking on a plank and if I just tip, I'm going to fall and I'm going to die. It's amazing how that feels so real. And so what we had is we had our participants go up and they maybe took like one little step. We asked them, how are you feeling?

And we also measured skin conductance response because when you are anxious, you sweat and skin conductance response goes up. And what we found is at the beginning, they were very anxious and they only took a few steps. But over time, people were just jumping off the plank with no anxiety response whatsoever. And what was interesting is that those individuals that habituated faster, so it only took them a few times to like not feel any fear or anxiety at all, we had this questionnaire asking them about risk taking in real life,

whether it's sports or driving or unsafe sex, and those people who we could measure that their emotional habituation was really fast, right? Those are the people who really took risks in life. So we've looked at the role of habituation when it comes to risk, but that's not the only domain in which we can see habituation when it comes to negative things. You've also looked at habituation when it comes to dishonesty.

Can you tell me how you've designed those studies? What is the setup of those studies? We were interested in whether people habituate to their own lying. Most people think that lying is immoral, right? But if your emotional response will go down over time the more you lie, then you'd probably lie more and more and more. And this is exactly what we tested.

So we had people come into the lab and we asked them to play a game. And in this game, they realized that if they lied to the other person they could gain more money at the expense of the other person. And we also recorded their brain activity and what we found that at the beginning they liked but just a little bit maybe a few cents. Next time they had an opportunity maybe a few dollars and the amount by which they lied became bigger and bigger, right? It's like the slippery slope. And at the same time, we looked at activity in their amygdala. So the amygdala is a small part of the brain, and it is important for emotional

arousal. And what we found is at the beginning, when people lied, there was a strong emotional response, right? They felt bad about lying. The next time they lied, less of an emotional response. The third time they lied, less. And as the amygdala activity went down, indicating less emotional arousal, people lied more and more and more. That study looks at how we habituate to our own lying, but you also habituate to the lies of other people. If you are in an environment, let's say a work environment, where people are lying, but they start with small lies. You know, maybe they lie a little bit about their expenses, you know, maybe they lie a little bit to the client about what the product can do, and then they lie more and more and more. They start really taking in, you know, thousands of dollars that they shouldn't

You are more likely to just accept and maybe not even notice if the lies are gradual and We see this in reality when people who have Been quite dishonest Bernie Madoff, for example, they actually tell you about how they started out with small lies and became bigger and bigger. There's a wonderful quote by him. He says, it start out with you taking a little bit, maybe a few hundred, a few thousand, you get comfortable with that and before you know it, it snowballs into something big. And what I like about this

quote is that he says you get comfortable with that. What this tells me is that he probably felt bad about it when he began, but over time, habituation, he became comfortable. Then he can lie more and more. So along the same lines, Tali, I'm guessing we can also habituate to other problematic things, things like misinformation or pollution or corruption. You know, if these are things that are all around us all the time, after some time it becomes hard to muster a sense of outrage.

Yeah, absolutely. With misinformation actually, there's surveys showing that they ask people, do you think it's okay to kind of fudge a story in order to get more clicks? And the percentage of people who said it's okay to kind of fudge a story in order to get more more clicks and the percentage of people who said it was okay was much smaller about 15 years ago than it is today. So I think with all this kind of like fake news and misinformation online, social media, we started becoming just used to this. We're not as outraged when we learn that someone is changing the story a little bit or maybe just making it up completely.

It seems that we accept it and we don't have much of an emotional response and probably we don't notice it as much. So, you know, we've looked at sort of many examples of habituation here when it comes to risk, to misinformation, to dishonesty. But at a grander level, I'm also wondering whether it works at the level of societies. When you look at the rise of authoritarian states, for example, sometimes they take away the rights of minorities, but they don't do everything on day one.

On day one, it's just a little bit. On day 10, it's a little more. And then by day 500, they've taken away a lot, but by that point, people have become desensitized through the same process of habituation. Right. I think when we look back at the history of humanity, there are all these dark stories of oppression and bloody wars and genocide. And we often look back and we said, how could that be? Right? Why wasn't that stopped earlier? And I think part of the answer is that these extreme political movements and deadly conflicts, they start small and then they increase gradually.

And because they increase very gradually, they end up eliciting a weaker emotional reaction. And because there's less emotional reaction, there's less resistance and more acceptance than there would otherwise be. And we talk about this in our book, and we take Nazi Germany as an example. And there's a lot of testimonies of, for example, German citizens that explain what happened. And when you kind of read those testimonies, they often talk about how things really escalated slowly. Right? People say that each act and each occasion was worse than the last, but only by a little bit. Right?

So we started by Jews are not allowed to be doctors, not allowed to be journalists, and books are burned. And then, you know, there are hundreds and hundreds of steps. And the last one is mass murder, is genocide, right? If the last act was a first act, that would, I believe, would have resulted in much more of a reaction from the people. But it's not. And there's this quote from a German citizen that he says that people could not see it developing from day to day like a farmer in the field that doesn't see the corn growing.

Right? It grows slowly slowly and then one day it's over. There are many other scenarios in which our tendency to habituate to bad things can bring terrible consequences. One example, climate change. Many of the warning signs of climate change are subtle and easy to miss. But even when they are stark and dramatic, think of melting ice caps or raging wildfires or dramatic flooding. Our minds habituate to these phenomena. They become expected, normalized.

Yeah, so the problem here is that first of all, perceptually we habituate, right? When things, let's say pollution, if there's pollution in the air constantly, we kind of get used to it and we don't really notice it's in the air. There's a really interesting survey that shows that in the UK, only 10% of people rate their air quality as poor, despite the fact that pollution breaches legal limits in 88% of UK regions. And then there's also just kind of more of accepting of this idea. Over time, we accept the idea that there's climate change and that there are going to be hurricanes or things like that. And so we have less of a reaction to it. And in fact, that's also been shown nicely on

Twitter. So there's a study where they looked at people, what they said about extreme climate events on Twitter. What they found is that extreme climate events, like hurricanes for example, as they became more and more frequent, people stopped tweeting about it. And on average, it took between two to eight years for people to stop tweeting about climate events, like extreme temperature.

And if you don't see it and you don't talk about it, then you don't act. So what is the solution for this, Tali? I understand how habituation can work with climate change, but is there a way to fight it? Well, I think the solution here is not to rely on our perception, to rely on instruments. The instruments can tell us quite

well what is happening with the temperature, with climate events, and we should we need to rely on the data, not on our feelings or how we perceive the world to be. It's just not reliable. Because of course I think what you're pointing out is that, you know, our perceptions might habituate to climate change, but our instruments will not, and they will continue to tell us the story. And if we can't trust our own intuitions, what we can trust is the data coming in

from our instruments. Right, but you know, it's really hard for people to do that. It's really hard for us to say, I'm gonna ignore my perception, I'm gonna rely on the instrument. This is a well-known problem. Often pilots are flying and they can go into vertigo and they feel like they're flying up towards,

you know, up in the air, when in fact they're flying down towards the ground. And the instruments show them, you're flying down towards the ground, but they feel like they're flying up. And it's really hard to just say, okay, I'm going to go with the instrument, right? I'm going to fly my plane into what I believe is into the ground because the instrument is telling me, no, this is a way you should do it. And that can lead to accidents and it has led to accidents.

I mean, so much of the story is about how our brains have this propensity to forget and ignore and eventually not notice something and how in some ways this can be functional in some elements of our lives. But in other situations, it really is helpful to be able to slow down, to be able to see again. There's not sort of a one size fits all rule when it comes to habituation and dishabituation, is there? Yeah. On one hand, we all want to have that joy again of the things that have been around

us for a long time. And we can remember in the past how much joy they had triggered in us, but now we have habituated. So we want to do these things that can maybe cause us to feel more of the happiness and the joy, but also to be able to see things around us, like cracks in our relationships, inefficiencies at work, but also the bigger things, racism and sexism,

so we can act to change them. Tali Sharad is a cognitive neuroscientist at University College London. Along with Cass Sunstein, she's the author of Look Again, The Power of Noticing What Was Always There. Tali, thank you for joining me today on Hidden Brain. Thank you so much for having me. It was a pleasure. Hidden Brain is produced by Hidden Brain Media. Our audio production team includes Annie Murphy-Paul, Kristen Wong, Laura Quirell, Ryan Katz, Autumn Barnes,

Andrew Chadwick, and Nick Woodbury. Tara Boyle is our executive producer. I'm Hiddenbrains executive editor. Over the past year we've heard from many listeners who asked if we had plans to make our podcast subscription, Hiddenbrain Plus, available for users of Android phones. We're so pleased to share that Hiddenbrain Plus is now available across platforms and devices. You can sign up via our Patreon page, just go to support.hiddenbrain.org. That site again is support.hiddenbrain.org. Of course, you can still find us on Apple Podcasts by searching for Hidden Brain and

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