The optimism bias - Tali Sharot

I'm gonna talk to you about optimism, or more precisely, the optimism bias. It's a cognitive illusion that we've been studying in my lab for the past few years, and 80% of us have it. It's our tendency to overestimate our likelihood of experiencing good events in our lives and underestimate our likelihood of experiencing bad events.

So, we underestimate our likelihood of suffering from cancer or being in a car accident. We overestimate our longevity and our career prospects. In short, we're more optimistic than realistic, but we are oblivious to the fact.

Take marriage, for example. In the Western world, divorce rates are about 40%. That means that out of five married couples, two will end up splitting their assets. But when you ask newlyweds about their own likelihood of divorce, they estimate it at 0%. Even divorce lawyers, who should really know better, hugely underestimate their own likelihood of divorce.

So it turns out that optimists are not less likely to divorce, but they are more likely to remarry. In the words of Samuel Johnson, "remarriage is a tribe of Hope over experience." If we're married, we're more likely to have kids, and we all think our kids will be especially talented. This, by the way, is my two-year-old nephew, Guy. I just want to make it absolutely clear that he's a really bad example of the optimism bias because he is, in fact, uniquely talented.

I'm not alone; out of four British people, three said that they were optimistic about the future of their own families—that's seventy-five percent—but only thirty percent said that they thought families in general are doing better than a few generations ago. This is a really important point because we're optimistic about ourselves, we're optimistic about our kids, we're optimistic about our families, but we're not so optimistic about the guy sitting next to us.

We're somewhat pessimistic about the fate of our fellow citizens and the fate of our country. But private optimism about our own personal future remains persistent. It doesn't mean that we think things will just magically turn out okay, but rather that we have the unique ability to make it so.

Now, I'm a scientist. I do experiments, so to show you what I mean, I'm gonna do an experiment here with you. Okay, so I'm gonna give you a list of abilities and characteristics, and I want you to think for each of these abilities where you stand relative to the rest of the population.

The first one is getting along well with others. Who here believes they're at the bottom 25%? Okay, that's about ten people out of fifteen hundred, I think. Who believes they're at the top 25%? That's most of us here. Okay, now do the same for your driving ability, how interesting are you, how attractive are you, how honest are you, and finally, how modest are you?

So, most of us put ourselves above average on most of these abilities. Now, this is statistically impossible; we can't all be better than everyone else. But if we believe we're better than the other guy, well, that means that we're more likely to get that promotion, to remain married because we're more social, more interesting, and it's a global phenomenon.

The optimism bias has been observed in many different countries, in Western cultures and non-Western cultures, in females and males, and in kids and the elderly. It's quite widespread. But the question is, is it good for us?

Some people say no; some people say the secret to happiness is low expectations. I think the logic is something like this: if we don't expect greatness, if we don't expect to find love and be healthy and successful, then we're not gonna be disappointed when these things don't happen. And if we're not disappointed when good things don't happen, and we're pleasantly surprised when they do, we will be happy.

So it's a very good theory, but it turns out to be wrong for three reasons. Number one: whatever happens, whether you succeed or you fail, people with high expectations always feel better. Because how we feel when we get dumped or when we're employee of the month depends on how we interpret that event.

The psychologists Margaret Marshall and John Brown studied students with high and low expectations and found that people with high expectations attribute their success to their own traits. "I am a genius, therefore I got an A; therefore, I'll get an A again and again in the future."

When they failed, it wasn't because they were dumb, but because the exam just happened to be unfair. Next time, they will do better. People with low expectations did the opposite, so when they failed, it was because they were dumb, and when they succeeded, it was because the exam just happened to be really easy. Next time, reality would catch up with them, so they felt worse.

Number two: regardless of the outcome, the pure act of anticipation makes us happy. The behavioral economist Georg Lowenstein asked students, including university students, to imagine getting a passionate kiss from a celebrity—any celebrity. Then he said, "How much are you willing to pay to get a kiss from a celebrity if the kiss was delivered immediately, in three hours, in 24 hours, in three days, in one year, in ten years?"

He found that the students were willing to pay the most not to get a kiss immediately but to get a kiss in three days. They were willing to pay extra in order to wait. Now, they weren't willing to wait a year or ten years. I mean, no one wants an aging celebrity, but three days seemed to be the optimum amount.

So why is that? Well, if you get the kiss now, it's over and done with. But if you get the kiss in three days, well, that's three days of jittery anticipation, the thrill of the wait. The students wanted that time to imagine: "Where is it gonna happen? How is it going to happen?" Anticipation made them happy.

This, by the way, is why people prefer Friday to Sunday. It's a really curious fact because Friday is a day of work and Sunday is a day of pleasure. So you would assume that people will prefer Sunday, but they don't. It's not because they really, really like being in the office and can't stand strolling in the park or having a lazy brunch.

We know that because when you ask people about their ultimate favorite day of the week—surprise, surprise!—Saturday comes in at first, then Friday, then Sunday. People prefer Friday because Friday brings with it the anticipation of the weekend ahead.

All the plans that you have on Sunday, the only thing you can look forward to is the workweek. So, optimists are people who expect more kisses in their future, more strolls in the park, and that anticipation enhances their well-being. In fact, without the optimism bias, we would all be slightly depressed.

People with mild depression, they don't have a bias. When they look into the future, they're actually more realistic than healthy individuals. But individuals with severe depression, they have a pessimistic bias, so they tend to expect the future to be worse than it ends up being.

So optimism changes subjective reality. The way we expect the world to be changes the way we see it. But it also changes objective reality; it acts as a self-fulfilling prophecy. And that is a third reason why lowering your expectations will not make you happy. Controlled experiments have shown that optimism is not only related to success; it leads to success.

Optimism leads to success in academia, sports, politics, and maybe the most surprising benefit of optimism is health. If we expect the future to be bright, stress and anxiety are reduced. So, oh no! Optimism has lots of benefits.

But the question that was really confusing to me was: how do we maintain optimism in the face of reality? As a neuroscientist, this was especially confusing because, according to all the theories out there, when your expectations are not met, you should alter them. But this is not what we find.

We asked people to come into our lab in order to try and figure out what was going on. We asked them to estimate their likelihood of experiencing different terrible events in their lives. For example, "What is your likelihood of suffering from cancer?" Then we told them the average likelihood of someone like them to suffer these misfortunes.

So cancer, for example, is about 30%, and then we asked them again: "How likely are you to suffer from cancer?" What we wanted to know was whether people would take the information that we gave them to change their beliefs. And indeed they did, but mostly when the information we gave them was better than what they expected.

So, for example, if someone said, "My likelihood of suffering from cancer is about 50%," and we said, "Hey, good news! The average likelihood is only 30%," the next time around they would say, "Well, maybe my likelihood is about 35%."

So they learned quickly and efficiently. But if someone started off saying, "My average likelihood of suffering from cancer is about 10%," and we said, "Hey, bad news! The average likelihood is about 30%," the next time around they would say, "Yep, still think it's about 11%."

So it's not that they didn't learn at all; they did, but much, much less than when we gave them positive information about the future. It's not that they didn't remember the numbers that we gave them. Everyone remembers that the average likelihood of cancer is about 30% and the average likelihood of divorce is about 40%. But they didn't think that those numbers were related to them.

What this means is that warning signs such as these may only have limited impact. Yes, smoking kills, but it mostly kills the other guy. What I wanted to know was, what was going on inside the human brain that prevented us from taking these warning signs personally? But at the same time, when we hear that the housing market is hopeful, we think, "Oh, my house is definitely gonna double in price."

To try and figure that out, I asked the participants in the experiment to lie in a brain imaging scanner. It looks like this. Using a method called functional MRI, we were able to identify regions in the brain that were responding to positive information. One of these regions is called the left inferior frontal gyrus.

So if someone said, "My likelihood of suffering from cancer is 50%," and we said, "Hey, good news! The average likelihood is 30%," the left inferior frontal gyrus would respond fiercely. And it didn't matter if you were an extreme optimist, a mild optimist, or slightly pessimistic; everyone's left inferior frontal gyrus was functioning perfectly well, whether you're Barack Obama or Woody Allen.

On the other side of the brain, the right inferior frontal gyrus was responding to bad news. And here's the thing: it wasn't doing a very good job. The more optimistic you were, the less likely this region was to respond to unexpected negative information. And if your brain is failing at integrating bad news about the future, you will constantly leave your rose-tinted spectacles on.

So we wanted to know: could we change this? Could we alter people's optimism bias by interfering with the brain activity in these regions? And there's a way for us to do that. This is my collaborator, Rio de Cali, and what he's doing is he's passing small magnetic pulses through the skull of the participant in our study into their inferior frontal gyrus.

By doing that, he's interfering with the activity of this brain region for about half an hour; after that, everything goes back to normal, I assure you. So let's see what happens. First of all, I'm gonna show you the average amount of bias that we see.

So if I was to test all of you now, this is the amount that you would learn more from good news relative to bad news. Now we interfere with the region that we found to integrate negative information in this task, and the optimism bias grew even larger. We made people more biased in the way that they process information.

Then we interfered with the brain region that we found to integrate good news in this task, and the optimism bias disappeared. We were quite amazed by these results because we were able to eliminate a deep-rooted bias in humans. At this point, we stopped and asked ourselves: would we want to shatter the optimism illusion into tiny little bits?

If we could do that, would we want to take people's optimism bias away? Well, I've already told you about all of the benefits of the optimism bias, which probably makes you want to hold on to it for dear life. But there are, of course, pitfalls, and it would be really foolish of us to ignore them.

Take, for example, this email I received from a firefighter here in California. He says, "Fatality investigations for firefighters often include: we didn't think the fire was going to do that," even when all the available information was there to make safe decisions. This captain is gonna use our findings on the optimism bias to try to explain to the firefighters why they think the way they do, to make them acutely aware of this very optimistic bias in humans.

So unrealistic optimism can lead to risky behavior, to financial collapse, to faulty planning. The British government, for example, has acknowledged that the optimism bias can make individuals more likely to underestimate the cost and duration of projects, so they have adjusted the 2012 Olympic budget for the optimism bias.

My friend, who's getting married in a few weeks, has done the same for his wedding budget. And by the way, when I asked him about his own likelihood of divorce, he said he was quite sure it was zero percent.

So what we would really like to do is we would like to protect ourselves from the dangers of optimism, but at the same time, remain hopeful, benefiting from the many fruits of optimism. I believe there's a way for us to do that. The key here really is knowledge.

We're not born with an innate understanding of our biases. These have to be identified by scientific investigation. But the good news is that becoming aware of the optimism bias does not shatter the illusion. It's like visual illusions in which understanding them does not make them go away. And this is good because it means we should be able to strike a balance to come up with plans and rules to protect ourselves from unrealistic optimism, but at the same time, remain hopeful.

I think this cartoon portrays it nicely because if you're one of these pessimistic penguins up there who just does not believe they can fly, you will certainly never will. Because to make any kind of progress, we need to be able to imagine a different reality, and then we need to believe that that reality is possible.

But if you are an extreme optimistic penguin who just jumps down blindly, hoping for the best, you might find yourself in a bit of a mess when you hit the ground. But if you're an optimistic penguin who believes it can fly but then adjusts a parachute to your back just in case things didn't work out exactly as you planned, you will soar like an eagle, even if you're just a penguin.

Thank you.