How the brain decides what to think

Neuroscientist Tali Sharot has been described as an “expert on human decision-making.” Sharot—a self-proclaimed people nerd who says an interest in people is the drive for her profession—is the founder of the Affective Brain Lab at University College London and a visiting faculty member at MIT. Her work looks at both the internal and external factors that influence how we think about the world around us, and how for most of us, a bias toward optimism shapes our thinking. In her first book, The Optimism Bias, (based on her cover story for TIME magazine), and her 2012 TED talk, Sharot posited that this natural bias toward believing we’re “above average” reveals something critical about how humans are wired. The optimism bias, Sharot says, not only helps us adapt to what’s currently happening around us, but helps us imagine and prepare for what we think will happen. “We have memory,” Sharot says, “not so we can remember the past, but so we can envision and plan for the future.”

Her most recent book, The Influential Mind: What the Brain Reveals About Our Power to Change Others, goes even deeper, looking at how we’ve evolved to be influenced, and what that means in a 21st century world. dscout sat down with Sharot to talk about the implications for researchers when it comes to optimism, influence, and the intricacies of the human brain.

dscout: In your first book, "The Optimism Bias,” you talk about the idea that we're privately optimistic. The idea that people tend to be very optimistic about themselves, and their abilities and futures, but more pessimistic, or realistic, about others.

Tali Sharot: I think when people hear that we have a bias toward optimism they’re kind of surprised, because people tend to complain about a lot of things. But the optimism bias doesn't necessarily mean that we have positive expectations. All it means is our expectations are better on average than what the future holds. And the optimism bias is mostly about ourselves, about our own futures, or the future of our kids. It’s not necessarily about the world at large. Someone with negative expectations can still be optimistically biased, but when it comes to ourselves, our bias is skewed. We underestimate some things, like our likelihood of divorce, the likelihood we’ll get cancer, and overestimate others, like the chances of our professional success. What I’m interested in is why we have this private optimism and public despair.

There are two major reasons. The first is control. One big reason we’re optimistic is that we believe we have control over our own future. We believe we can steer the wheel in the right direction. That we can make a relationship work, or get a promotion by working hard, or that our children will be gifted because of how we educate them. We don't believe, however, that we have control over the world at large. We don't think we have control over where our leaders are taking us or climate change. Those things that we don’t have control over, those are the things we’re less likely to conclude will head in a positive direction. That's the most important reason why there's this distinction.

The second reason has to do with comparison, and believing we’re doing better than others around us. Comparison is extremely important to our evaluation of ourselves and for our happiness. We are much happier when we believe we're doing better than others. For example, let’s say your salary is a hundred thousand dollars a year. If you think everyone else around you is making two-hundred thousand dollars a year, you’ll be unhappy. But if you think everyone around you is making fifty-thousand dollars a year, you’ll be happier.

So regardless of actual circumstance, our overall satisfaction is really about how we perceive that circumstance, in relationship to others. 

Yes exactly. 

That optimism, regardless of circumstance, also seems connected to anticipation, which is something else you’ve looked at. The idea that we prefer Friday to Sunday, because on Friday we can anticipate all of the good things that are going to happen, and on Sunday those things have already happened.  

Yes. We’ve seen research that shows people are happier before they go on vacation, because they’re so excited about how much fun it will be, or how relaxing it will be. And then they go, and it’s great, but maybe not as great as they thought it would be. So they’re happier before they go on the trip than when they’re actually on it. But I also think we tend to believe that events like that will make us happier than they actually will. That’s a bit like the impact bias.

The optimism bias is mostly about probabilities; about thinking negative events are less likely to happen and positive events are more likely to happen. The impact bias is about how things will impact you if they do happen. For instance, we don’t think we’re likely to get divorced, but if it does happen, we think it will be really, really bad. In reality, if it does happen, people find it doesn’t end up feeling as bad as they thought it would feel. But it works both ways. People think, if they win a prize, they’ll be ecstatically happy. But then they get the prize and they’re not as happy as they thought they would be. So generally, we think good  things will make us feel better than they actually do, and we think bad things will make us feel worse than they actually do. In that way, the optimism bias and the impact bias go hand in hand.

That also seems connected to another idea you’ve spoken about, which is “cognitive time travel.” That to form projections about how we think something will make us feel, we have to imagine or to imagine some future event, or time travel in our minds, and that the brain doesn’t do that randomly.

Yes. Mental time traveling is simply the idea that to envision the future we use memories from our past. We use the same system in the brain, the hippocampus and regions next to the hippocampus, to remember the past and to imagine the future. It makes sense, because to imagine the future we need to take bits and pieces of the past and put them together. Reconstruct them to create something new. Say, for instance, I’m imagining my Christmas vacation. In order to do that I'm retrieving memories of my past Christmas vacations or movies that I've watched, and I’m putting those pieces together to create a new image of my Christmas vacation that is about to happen. We have memory not so we can remember the past, but so we can envision and plan for the future.

And our brains encode desirable information more than they encode undesirable information?

Yes. That’s part of what we were confused about in our research with the optimism bias. Every learning theory suggests when something happens and it doesn't meet your expectations, you should revise your expectations, right? But what we found in our research is that when an event goes better than you expected, you learn more than you do when an event goes worse than expected. That's how people maintain the optimism.

Does that affect how people recall or remember their own experiences? Is it something that we should account for when asking people questions about themselves?

Actually, when it comes to memory, what matters is arousal, and not surveillance. We remember arousing events really well, whether they’re positive or negative.People remember any kind of trauma quite well, they remember an accident that they were in. But they also remember really positive events, the birth of a child, meeting a loved one or something like that.

People do tend to cling to the past in a way that's self-serving. So, although we will remember positive and negative events both very well, any memory or event that is self-serving is likely to be remembered better than a memory that isn't self-serving. But the effect is not as strong as when you try to imagine the future. 

Let's say I failed in an exam. Will I remember it? It's an arousing event. I failed, I will remember it. But then, what I might say to myself is something more self-serving, that I failed the exam not because I’m stupid, but because the exam wasn’t fair, or perhaps I just didn't study enough. The conclusion I draw is that next time I should study more, so I’ll succeed. It’s not that we don't remember that we failed. We remember that we failed, in order to enable us to figure out what we need to do in order to succeed the next time around.

As humans, we rationalize things to put ourselves in a good light. Self-illusion is very, very, very strong. Say for example, I ask you to estimate the likelihood that you’ll get cancer in your lifetime. And then after you’ve estimated it, I tell you that for most people your age or in your demographic, that likelihood is about 30%. And then I ask you to re-estimate what your likelihood is. If you thought you were 70% likely to get cancer, then when I tell you that it’s more like 30%, you’ll learn from that quite quickly. But if you thought you were about 10% likely to get cancer, and I tell you the likelihood is closer to 30%, you don’t learn as well.

We go about life getting information from all sorts of places. Some of it comes from things that happen to us, but some of it comes from talking to people, from reading, from observing other people. And most of this information is a little bit ambiguous in what it means for the future. Because you can remember a lot of things, but the question is, do you learn from it?

Your latest book is “The Influential Mind,” which looks closely at how we influence, and how we’re influenced by, those around us. And today, more people wield influence than maybe ever before, in large part thanks to social media, which has opened up a lot of avenues of influence that hadn’t existed previously—which means we’re not always aware of when we’re being influenced. So, how do we know when we’re being influenced? What are the things we should be mindful of?

It's interesting how the word influence has a negative connotation. Being influenced is not a bad thing. We are influenced by everyone, all the time, without knowing it. And it's mostly good that we are, because we can't live based on our experiences only, and our knowledge only, right? Our knowledge comes from other people, other people's research, other people's experience. We learn from other people. Children are influenced by their parents, and that's how they learn everything. We’re supposed to be influenced, that’s how we’ve been built as a species and it’s part of why we’re so successful as one. We shouldn’t look at influence as a bad thing. That's the idea of communication. We want to be influenced emotionally, we want to be influenced intellectually.

Of course, it could be negative, if someone has bad intentions. That’s one obvious problem, if someone is trying to influence you because they have intentions that aren’t compatible with your goals. Another big problem is when you’re trying to make a decision or to form an opinion, but there are too many people or sources of information influencing you. That can lead to confusion, or difficulty discerning what’s best for you. When it comes to choices and preferences, we need to learn from others, but also pay attention to ourselves. Even if something is right for the majority of people, it may not necessarily be right for the individual.

The modern problem now is a huge amount of malintention, where people are giving others misinformation on purpose to try to influence them. That happens a lot on social media and it's hard to know when it’s happening. In life you don't interact with many people that have bad intentions toward you. And in a live situation it’s also easier to detect people’s intent from the way they look, their facial expressions and tone. You pick up cues as to whether someone knows what they’re talking about.

We evolved in small groups, and to learn from other people, which was helpful because the people around us typically had information that was very relevant to us. Now we get information from everywhere, and from all people from all over. That’s good because it’s a diversity of perspectives, but it’s harder to distinguish what’s relevant and what isn't, and who has good intentions vs. who has bad intentions.

It's interesting, because for a long time quite a bit of qualitative research was conducted in group settings. Now, we have the tech to do qual at a larger scale individually. But in terms of influence, if you are in a group of six people, and you're all asked a question, as a researcher you have to think about how what the first five people said influenced the last person. Whereas with something like social media that’s more stealth, you may not know the extent to which someone has been influenced. Is face-to-face influence different than online influence?

The research shows that all of the principles are the same. Usually what we see is that in both cases people are influenced, and there are two main reasons why. One is that other people have information. So if everyone says “chicken is good,” I'm more likely to believe chicken is good, because these other people who are saying that have information that has led them to that conclusion. The second reason is not wanting to be different—if everyone says they like chicken, I'm just going to say I like chicken too, because I want to be a part of the group, I don't want to be different from the norm.

The consequence of that is what we call private conformity and public conformity, a bit like the private and public optimism. Private conformity is actually changing one’s preference, and deciding you do really like chicken. Public conformity is not actually changing a preference, just saying that you’ve changed a preference. All of that happens both online and in groups.