Making the World Sparkle Again

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, you know, 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. Support for Hidden Brain comes from Planet Visionaries. Professional climber and environmental advocate Alex Honnold hosts Planet Visionaries, a podcast spotlighting the people tackling climate challenges with real, hopeful solutions. Throughout season 6, Alex brings together extraordinary changemakers for powerful conversations about grit, determination, and the power of hope to fuel our fight for a better future. In partnership with the Rolex Perpetual Planet Initiative, this is Planet Visionaries. Listen or watch wherever you get your podcasts.

Quick question. Do people come to you for answers at work? Maybe you're managing projects, training new hires, or just the one everyone relies on. That's leadership. Through UVA Darden's Part-Time MBA in Rosslyn, we help professionals like you turn real-world experience into recognized leadership credentials. without stepping away from your career. Whether you work in healthcare, education, government, or business, this is how you take the next step. Learn more at darden.virginia.edu/ptmba.

Support for Hidden Brain comes from Progressive. Whoever says saving money is hard doesn't know that new customers who bundle and save with Progressive save hundreds. Because switching your home and auto insurance is better than cutting down on those iced lattes you love. Switch to Progressive and see if you could save. Get your quote today at progressive.com. Progressive Casualty Insurance Company affiliates and other insurers. Not available in all states. 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 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 Sharot at University College London. Tali Sharot, 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 2 really interesting things. The first was that the holidaymakers were the happiest 43 hours in. Why is that? Well, 43 hours allowed them time to get settled and unpack, 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, but on day 8, they weren't as happy as they were on day 7. Day 7, not as happy as day 6, 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, like a great example of habituation, right? When you see, 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 2 years. And also, attraction 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, you know, 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 in 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? 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 2 kids and we were living in the city in a place that was a little bit too small, I think, for a family of 4. But it was fine. before the pandemic because we, 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. 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 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, 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 a 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, and, you know, 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, 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, right? 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, as a society. And maybe the third important factor is wellbeing 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 a 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 wellbeing 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 that are scary, shady, and sad. You're listening to Hidden Brain. I'm Shankar Vedantam.

Quick question. Do people come to you for answers at work? Maybe you're managing projects, training new hires, or just the one everyone relies on. That's leadership. Through UVA Darden's Part-Time MBA in Rosslyn, we help professionals like you turn real-world experience into recognized leadership credentials. without stepping away from your career. Whether you work in healthcare, education, government, or business, this is how you take the next step. Learn more at darden.virginia.edu/ptmba.

Support for Hidden Brain comes from Progressive. Whoever says saving money is hard doesn't know that new customers who bundle and save with Progressive save hundreds. Because switching your home and auto insurance is better than cutting down on those iced lattes you love. Switch to Progressive and see if you could save. Get your quote today at progressive.com. Progressive Casualty Insurance Company, affiliates, and other insurers. Not available in all states. This is Hidden Brain. I'm Shankar Vedantam. Tali Sharot 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, right? 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 dishabituation 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. 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 resparkles. I mean, that quote is great, but the word resparkles is something that we really liked, right? How do you just take the ordinary life and make it resparkle? And what Julia is, 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 re-sparkle.

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, we— I actually heard this podcast with Jodie Foster, and she talks about how she was away on set filming for 6 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 6 months ago, I'm sure I was bored by, 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 6 months ago were sort of what I was trying to escape from, now everything is amazing. I mean, I can tell you that when, when I go away for a long time and I come back, I just have this joy. You know, my bed is like amazing, and then, you know, the view from, from the window is amazing.

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 gonna 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 6 minutes. Every time you change, it lasts only for about 6 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 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 gonna 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. Another example is, 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.

Hmm.

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, 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 $5, and they said, take the $5 and buy whatever you want for yourself. You know, you could buy a coffee, you could buy a pen. Day number 2, $5, buy whatever you like. Day number 3, $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 some— 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, you know, drinking the coffee or using your sparkly pen.

You say 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, well, 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 'cause 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, Tali?

Yeah, no, it's not. Because let's, let's go back to the vacation example. The most like happiest time was 43 hours in. And the word that they used most to describe the best parts of the vacation was first, first, first, first. So then really what that means is that you wanna create more firsts. You wanna create more 43 hours in, right? So instead of going for a long 2-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—

Firsts.

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 listened 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 enjoyed 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, they, they did the same study with massages. Do you wanna have the massage from beginning to end, no interruptions, or do you wanna have it with breaks? People wanted beginning to end, no interruptions, but in fact enjoy it more if there are breaks. And there is an economist named, uh, Typer Skitovsky, um, who has a quote which really puts this in, 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, you know, 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 half to your partner.

So on the flip 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 whole. 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 and a break, 20 minutes and a break, what happens is that I'm breaking my habituation to the bad. So if you're doing like cleaning, for example, there's maybe like a bad smell of, of the cleaning products, but you habituate to it so you don't smell it anymore, right? And that's good, right? 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 going to feel again bad, right? I'm going to, 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. And the advice, actually, in both situations is to do exactly the opposite.

Yeah, and there are sayings about savoring or about, oh, get it over and done with. But then in reality, it's really hard, right? It's hard to savor. We, you know, if there's something good, we don't want to stop. And 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. Support for Hidden Brain comes from Instagram. Instagram Teen Accounts' automatic protections limit who can contact teens, the content they can see, and the time they spend on the app. Teens are automatically placed into Teen Accounts. Teens under 16 will need a parent's permission to change any of those settings to be less strict. Learn more about Teen Accounts and Instagram's ongoing work to protect teens online Quick question.

Do people come to you for answers at work? Maybe you're managing projects, training new hires, or just the one everyone relies on. That's leadership. Through UVA Darden's Part-Time MBA in Rosslyn, we help professionals like you turn real-world experience into recognized leadership credentials without stepping away from your career. Whether you work in healthcare, education, government, or business, this is how you take the next step. Learn more at darden.virginia.edu/ptmba.

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So there was a decade-long Boston Harbor cleanup. So if you visit Boston today, there's clear blue waters, you know, there's sailing boats all 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 cost $4 billion to clean up the harbor. And it was high risk the whole time. But at the very end, they sent 5 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 it's— the narrowest part of it was only 5 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 that were only about 30 inches wide, so they became kind of smaller and smaller. And despite that the project was pretty complex, the divers trained for it for only 2 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 3 of the 5 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, you know, all the measures. But then after, 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 is 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 to— 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 that's 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 lied, 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 starts 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. 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 OK to kind of fudge a story in order to get 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.

So 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 1. On day 1, 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. Now, 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, right? 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, 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 the 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 your head.

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. So, and then there's also just kind of more of accepting of this idea, right? 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 2 to 8 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, right? The instruments can tell us quite well what is happening with the temperature, with climate events, and 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 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 it's really hard for people to do that. It's really hard for us to say, I'm going to ignore my perception. I'm going to 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 the 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, I mean, on one hand, we all want to kind of 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 habituated. So, you know, 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 Sharot 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.

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