The Optimism Bias: A Tour of the Irrationally Positive Brain Read online

  Copyright © 2011 by Tali Sharot

  All rights reserved. Published in the United States by Pantheon Books, a division of Random House, Inc., New York.

  Pantheon Books and colophon are registered trademarks of Random House, Inc.

  Library of Congress Cataloging-in-Publication Data

  Sharot, Tali.

  The optimism bias : a tour of the irrationally positive brain / Tali Sharot.

  p. cm.

  eISBN: 978-0-307-37983-2

  1. Neuropsychology. 2. Optimism—Physiological aspects. I. Title.

  QP360.S466 2011 612.8—dc22 2010039692

  www.pantheonbooks.com

  Jacket design by Peter Mendelsund

  v3.1

  For my parents—

  Tamar and Steve Sharot

  Contents

  Cover

  Title Page

  Copyright

  Dedication

  PROLOGUE: A Glass Forever Half Full?

  1. Which Way Is Up?

  Illusions of the Human Brain

  2. Are Animals Stuck in Time?

  The Evolution of Prospection

  3. Is Optimism a Self-Fulfilling Prophecy?

  How the Mind Transforms Predictions into Reality

  4. What Do Barack Obama and Shirley Temple Have in Common?

  When Private Optimism Meets Public Despair

  5. Can You Predict What Will Make You Happy?

  The Unexpected Ingredient for Well-being

  6. Crocuses Popping Up Through the Snow?

  When Things Go Wrong: Depression, Interpretation, and Genes

  7. Why Is Friday Better Than Sunday?

  The Value of Anticipation and the Cost of Dread

  8. Why Do Things Seem Better After We Choose Them?

  The Mind’s Journey from Expectation to Choice and Back

  9. Are Memories of 9/11 as Accurate as They Seem?

  How Emotion Changes Our Past

  10. Why Is Being a Cancer Survivor Better Than Winning the Tour de France?

  How the Brain Turns Lead into Gold

  11. A Dark Side to Optimism?

  From World War II to the Credit Crunch—Underestimating Risk Is Like Drinking Red Wine

  EPILOGUE: A Beautiful Mademoiselle or a Sad Old Lady?

  From Prediction to Perception to Action

  ACKNOWLEDGMENTS

  NOTES

  About the Author

  Prologue

  A Glass Forever Half Full?

  I would have liked to tell you that my work on optimism grew out of a keen interest in the positive side of human nature. That would be a pleasant story: “A Cognitive Neuroscientist in Search of the Biological Basis of Our Hopeful Souls.” Pleasant but, unfortunately, untrue. I stumbled upon the optimism bias quite by accident while investigating people’s memories of the largest terrorist attack of our time. Back then, my scientific interests inclined more to the dark side: My principal research had been aimed at understanding how traumatic events shape our memories. I was interested in how the brain tricks us into believing that our recollections of exceptionally emotional events, such as the occurrences of September 11, 2001, are as accurate as a videotape, even when we are utterly mistaken.

  I had been conducting research at New York University for over a year when American Airlines Flight 11 and United Flight 175 were flown into the World Trade Center at 430 miles per hour. Shock, confusion, and fear were the common responses on the street. Such forceful emotions are exactly the sort of reactions that will generate unusually vivid memories, ones that are reluctant to fade away. These are commonly referred to as “flashbulb memories” because of their sharp-edged, picturelike qualities. In chapter 9, I tell the story of flashbulb memories—how we remember unexpected arousing events and how the structures deep in our brain “Photoshop” these images, adding contrast, enhancing resolution, inserting and deleting details.

  I was puzzled: Why had our brains developed a mechanism that would create highly vivid memories that were not necessarily accurate? Around the time my colleagues and I published our scientific investigation of memories of 9/11,1 a group of researchers at Harvard University proposed an intriguing answer. The neural system responsible for recollecting episodes from our past might not have been developed for that purpose at all. Rather, the core function of this system, which many had believed evolved for memory, may, in fact, be to imagine the future.2

  Brain-imaging studies show that the same brain structures that are engaged when we recollect our past are called upon when we think of the future.3 These two fundamental human thought activities rely on the same brain mechanisms; they draw on similar information and underlying processes. To imagine your upcoming trip to Barbados, for example, you need a system that can flexibly reconstruct novel scenarios, one that can take bits and pieces of memories from your past (your last vacation to a warm country, images of sandy beaches, your partner in his swimsuit) and bind them together to create something new (you and your loved one wearing straw hats on a beach in Barbados next month)—an event that has yet to happen. Because we use the same neural system to recall the past as we do to imagine the future, recollection also ends up being a reconstructive process rather than a videolike replay of past events, and thus is susceptible to inaccuracies.

  Was this theory correct? To discover the answer, I would record people’s brain activity while they imagined future events, then compare that activity to the pattern I observed when they were recollecting past events.

  The plan was simple. However, when I asked my volunteers to imagine future life events, something unexpected occurred. Even when given specific situations of the most humdrum kind (getting an ID card, playing a board game), people tended to fashion magnificent scenarios around them. They kept painting the most perfectly gray events in shades of pink.

  You would think that imagining a haircut in the future would be somewhat dull. Not at all. Getting a haircut today may be boring, but getting one in the future is a cause for celebration. Here is what one of my participants wrote:

  I projected that I was getting my hair cut to donate to Locks of Love [the nonprofit organization that provides hairpieces to children suffering from hair loss]. It had taken me years to grow it out and my friends were all there to help celebrate. We went to my favorite hair place in Brooklyn and then went to lunch at our favorite restaurant.

  I asked another participant to imagine a ferry ride. She responded:

  One to two years from now I see myself taking the ferry to the Statue of Liberty. The weather would be really nice and windy, so my hair would be blowing everywhere.

  The world, only a year or two into the future, was a wonderful place to live in. I spent hours with a student of mine, Alison Riccardi, trying to come up with exceptionally unexciting events that surely couldn’t provide any cause for celebration. All to no avail. Once people started imagining, the most banal life events seemed to take a dramatic turn for the better, resulting in a life that was just a bit less ordinary.

  These responses switched on a red (or at least pinkish) light in my mind. I was surprised by this tremendously powerful, seemingly automatic inclination to imagine a bright future. If all our participants insisted on thinking positively when it came to what lay in store for them personally, then there had to be a neurobiological basis for this phenomenon. We set aside our original project and went on to try to identify the neural mechanisms that mediate our optimistic tendencies.4

  How does the brain generate hope? How does it trick us into moving forward? What happens when it fails? How do the brains of optimists differ from those of pessimists? Although optimism is vital for our well-being and has an enormous impact on the economy, these questions have been left unanswered for decades. In this book, I argue that humans do not hold a positivity bias on account of having read too many self-help books. Rather, optimism may be so essential to our survival that it is hardwired into our most complex organ, the brain.

  From modern-day financial analysts to world leaders, newlyweds (all described in chapter 11), the Los Angeles Lakers (chapter 3), and even birds (chapter 2), optimism biases human and nonhuman thought. It takes rational reasoning hostage, directing our expectations toward a better outcome without sufficient evidence to support such a conclusion.

  Close your eyes for a moment and imagine your life five years from now. What sorts of scenarios and images pop into your mind? How do you see yourself professionally? What is the quality of your personal life and relationships? Though each of us may define happiness in a different way, it remains the case that we are inclined to see ourselves moving happily toward professional success, fulfilling relationships, financial security, and stable health. Unemployment, divorce, debt, Alzheimer’s, and any number of other regrettably common misfortunes are rarely factored into our projections.

  Are such unrealistic predictions of future bliss limited to thoughts of fundamental, life-altering events such as marriage and promotion? Or do optimistic illusions extend to more mundane, everyday events? Do we expect to get more work done this week than last? Do we expect tomorrow to be better than yesterday? Do we assume that next month will be filled, on the whole, with more enjoyable encounters than irritating ones?

  In the summer of 2006, I set out to research this more prosaic part of the equation. I was spending a few months working at the Weizmann Institute for Science in I
srael before starting a new job at University College London. Whatever the depth of my own optimistic nature, I wasn’t banking on getting too many sunny days once I got to the United Kingdom, so I was fairly determined to get some sun on my face for a few weeks before relocating to the English capital.

  The Weizmann Institute is about a twenty-minute drive from the bustling city of Tel Aviv. It’s a scientific oasis in the middle of the country, its well-tended greens reminiscent of those on a California campus. But if the institute feels peaceful in itself, it is no secret that the volatile politics of Israel are always close at hand. Most Weizmann students enter college after fulfilling their mandatory military service, a life experience that doesn’t necessarily incline one to be optimistic. With this in mind, I wondered about the extent to which they would be prone to the optimism bias. I recruited my sample group, then asked them about their expectations for the month ahead. On the most humdrum level, how likely did they think it was that they would be stuck in traffic sometime, or be more than half an hour late for an appointment? On a slightly more heightened level of anticipation, what did they think were their odds of having a sexual encounter they would regret, or one they would enjoy? Did they see themselves cooking an elaborate meal, receiving a surprise gift? I presented them with one hundred such questions.

  I have to say, the results astonished me, in that an overwhelming majority of the students expected more positive experiences than negative or even neutral ones, at a comparative rate of around 50 percent to 33 percent. That was not all: The positive incidents were also expected to occur sooner than the unpleasant or just plain boring ones. While the students generally expected to enjoy a nice evening out with a partner in the next few days, an argument with a boyfriend or girlfriend was anticipated—if at all—only toward the end of the month.

  On the off chance that my participants were leading charmed lives, I asked them to come back a month later and tell me which of those one hundred notional events they had actually experienced during that time. As it happened, positive, negative, and neutral everyday events had befallen them more or less equally, in roughly even 33 percent shares. The Weizmann students had not hit on the secret of human happiness; they had merely expressed a very ordinary optimism bias.

  In considering this example, you may be wondering whether optimism is truly a dominant trend in the population at large or, more specifically, a special delusion of youth. This is a fair question. You would think that as we grow older, we grow wiser. With more years of life experience behind us, we should be able to perceive the world more accurately—to distinguish delusions of hope from hard-core reality. We should, but we don’t.

  We wear rose-tinted glasses whether we are eight or eighty. Schoolchildren as young as nine have been reported to express optimistic expectations about their adult lives,5 and a survey published in 2005 revealed that older adults (ages sixty to eighty) are just as likely to see the glass half full as middle-aged adults (ages thirty-six to fifty-nine) and young adults (ages eighteen to twenty-five).6 Optimism is prevalent in every age group, race, and socioeconomic status.7

  Many of us are not aware of our optimistic tendencies. In fact, the optimism bias is so powerful precisely because, like many other illusions, it is not fully accessible to conscious deliberation. Yet data clearly shows that most people overestimate their prospects for professional achievement; expect their children to be extraordinarily gifted; miscalculate their likely life span (sometimes by twenty years or more); expect to be healthier than the average person and more successful than their peers; hugely underestimate their likelihood of divorce, cancer, and unemployment; and are confident overall that their future lives will be better than those their parents put up with.8 This is known as the optimism bias—the inclination to overestimate the likelihood of encountering positive events in the future and to underestimate the likelihood of experiencing negative events.9

  Many people are convinced that optimism was invented by Americans—a by-product of Barack Obama’s imagination, some believe. I encounter this notion often, especially when giving lectures in Europe and the Middle East. Yes, they say, celebrating future haircuts, imagining a sun-filled ferry ride, underestimating the likelihood of crippling debt, cancer, and other misfortunes are indicative of an optimism bias—but these are New Yorkers you are describing.

  True, my first investigation of optimism was conducted on residents of Manhattan. (I made a special effort to conduct all future investigations on cynical Brits and Israelis.) You could be forgiven for assuming that the Big Apple is the perfect setting for concerted research into optimism. Though I have no hard statistics at hand to substantiate this, pop culture would certainly have us believe that New York City is a lightning rod for individuals with big dreams and the self-belief to think these can be realized. From newly processed immigrants contemplating the Statue of Liberty to Holly Golightly admiring the window displays at Tiffany’s on Fifth Avenue, NYC is quite the poster child for all things hopeful: a city of teeming streets where people are continually hustling to be the Next Big Thing.

  To the surprise of some, however, the concept of optimism can easily be traced back to seventeenth-century European thought. The formulation of an optimistic philosophy took root not in American culture but in France. Descartes was one of the first philosophers to express optimistic idealization, in his trust that humans could master their own universe and thereby enjoy the fruits of the earth and the maintenance of good health. But the introduction of optimism as a technical term is usually credited to the German philosopher Gottfried Wilhelm Leibniz, who notably held that we live in “the best of all possible worlds.”10

  The results of having a positively biased view of the future can be quite dire—bloody battles, economic meltdowns, divorce, and faulty planning (see chapter 11). Yes, the optimism bias can sometimes be destructive. However, as we will soon discover, optimism is also adaptive. As with all other illusions of the human mind (such as the vertigo illusion and the visual illusions described in chapter 1), the optimism illusion had developed for a reason: It has a function.

  The optimism bias protects us from accurately perceiving the pain and difficulties the future undoubtedly holds, and it may defend us from viewing our options in life as somewhat limited. As a result, stress and anxiety are reduced, physical and mental health are improved, and the motivation to act and be productive is enhanced. In order to progress, we need to be able to imagine alternative realities—not just any old realities, but better ones, and we need to believe them to be possible.

  The mind, I argue, has a tendency to try to transform predictions into reality. The brain is organized in a way that enables optimistic beliefs to change the way we view and interact with the world around us, making optimism a self-fulfilling prophecy. Without optimism, the first space shuttle might never have been launched, peace in the Middle East would never have been attempted, rates of remarriage would likely be nonexistent, and our ancestors might never have ventured far from their tribes and we might all be cave dwellers still, huddled together and dreaming of light and heat.

  Fortunately, we are not. This book explores one of the greatest deceptions of which the human mind is capable: the optimism bias. It investigates when this bias is adaptive and when it is destructive, and it provides evidence that moderately optimistic illusions can promote well-being. It focuses on the specific architecture of the brain, which allows unrealistic optimism to be generated and alter our perceptions and actions. In order to understand the optimism bias, we first need to look at how, and why, the brain creates illusions of reality. We need to burst a giant bubble—the notion that we perceive the world as it really is.

  CHAPTER 1

  Which Way Is Up?