The Hidden Brain: How Our Unconscious Minds Elect Presidents, Control Markets, Wage Wars, and Save Our Lives

by Shankar Vedantam

  Trapped people seek consensus with those around them, even if acquiring such consensus wastes precious seconds. They follow one another, even if they know their comrades are going the wrong way. They help one another, even when such help is counterproductive. Rather than run to the nearest exit, they invariably try to leave a burning building the same way they entered it, which is why some exits during disasters remain unused, while crowds jam the main door.

  We often think trapped people place narrow self-interest above the greater good. This stereotype is again premised on the assumption that we are rational creatures focused on self-preservation. In reality, people can undermine themselves—and reduce the overall survival rate—by trying to help one another. Rather than run, they wait to make sure everyone has decided to run. If some people are injured and cannot move, others feel obliged to stay by their side, even if they can do nothing to help. The strong and able-bodied stand solicitously at exits to help the frail and elderly—and exacerbate crowding. Heroism—driven by unconscious algorithms in the hidden brain that elevate group interests above individual interests in a crisis—often causes unnecessary casualties. Beningo Aguirre told me that when he studied the September 11, 2001, attacks, he found only one person at the World Trade Center who behaved the way disaster models predict everyone should behave: The man heard an explosion, reached under his desk for his tennis shoes, laced up, and ran.

  The same patterns of behavior show up during larger-scale disasters. Reports from many coastal areas reveal that minutes before the 2004 tsunami in South and Southeast Asia struck, the sea began to recede. Fisherfolk in several countries gathered to discuss the phenomenon. They asked one another what was happening, not realizing the ocean was rearing its head like a cobra getting ready to strike. Like the people in the nightclub or the people in the World Trade Center, human beings given ambiguous warnings of disaster invariably turn to their friends and neighbors to seek consensus about what is going on.

  If individuals explicitly ask themselves whether those they are turning to really know much more than they do themselves, it is easy to acknowledge the obvious: The person sitting in the cubicle next to you probably has no better information than you do. But the desire to arrive at a shared understanding of what is happening is an extremely powerful drive of the hidden brain in situations of grave threat. An alarm is distressing; the consensus of the group is comforting. Like many biases of the hidden brain, this one works well much of the time. Sticking with the group in our evolutionary history usually offered safety. Sure, it sometimes backfired, but our brains have evolved to tell us what works in aggregate, and our evolved instincts for survival are consequently blunt. When an alarm goes off, it triggers anxiety, and the hidden brain instructs you to turn to the group because groups provided our ancestors with comfort and safety more often than they exposed them to danger and risk.

  In modern disaster situations, the comfort of the group regularly puts individuals at risk because threats are now so complicated that none of the members in the group knows what is happening. The point is not that groups always do the wrong thing. The point is that groups diminish our autonomy. Our comrades may not know what they are doing, but following them is much easier than going our own way. The group provides comfort, whereas going your own way triggers anxiety. But in disaster situations, anxiety is the right response; it is false comfort that is deadly.

  I juxtaposed the story of what happened on the Belle Isle bridge with what happened to the employees of Keefe, Bruyette & Woods on September 11, 2001, for an important reason. When we think about these cases in hindsight, it is very easy to draw the conclusion that the people in Detroit were callous cowards, and that the people in New York who stayed behind in the office tower were fools. In fact, if you subscribe to the theory that individuals always make autonomous, deliberate, conscious choices, these are conclusions you must reach. Only cowards fail to do what they know is right, and only fools keep sitting at their computers when the 110-story tower next door is burning to the ground—right? If you study these situations in the context of the hidden brain, however, you arrive at a completely different conclusion. For better and worse, people like Brad Fetchet and Tiffany Alexander were decisively influenced by the people around them, who were in turn influenced by the people around them.

  Our society does not believe the hidden brain exists, which is why we take only people’s conscious minds into account when we design emergency evacuation procedures. It is rational to assume that when a fire alarm goes off at a workplace, people will get up and leave. But they don’t. It seems implausible that in response to an alarm people who are working alone will jump up and run out of a building sooner than people working in large groups. But they do. In a rational world, larger groups should allow people to arrive at better conclusions because they collectively have a greater diversity of knowledge and experience. The problem is that in crises, individuals don’t bring their disparate insights and ideas to the group; the group imposes conformity on individuals. When experts create models about how people should evacuate tall buildings in emergencies, they assume people will behave like water molecules and flow out smoothly from all exits, as long as the exits are clear. But the hidden brain’s tendency to want to stick with the group means that humans in tall towers behave much more like molasses.

  How does the new understanding of the hidden brain change how people should be taught to prepare for disasters? First, people need to be warned about their tendency to abdicate decision-making to groups. Offices with a large number of workers need to have more training in disaster preparedness than those that have fewer workers. It is a good idea to have trained members on staff who quickly understand that the reason everyone is sitting quietly at their desks as a fire alarm screams its head off is not that people have secret knowledge that the alarm is a drill, but that they are, in effect, paralyzed by their comrades. On the morning of September 11, 2001, many lives on the eighty-eighth-floor offices of Keefe, Bruyette & Woods were saved because one man—J. J. Aguiar—raced through the floor screaming at everyone to evacuate. Aguiar could not have known that a second plane was coming, so his judgment was really a gamble. But that is often the nature of leadership, and it had the profound impact that leadership exerts—it galvanized people into action. What happened to Aguiar? After literally forcing his comrades to escape, he went up the tower to get people on other floors to evacuate. He never made it out himself.

  If even one person on the Belle Isle bridge had stepped forward to confront Martell Welch, there is no doubt in my mind that he or she would have instantly prompted many others to act, as J. J. Aguiar did on the eighty-eighth floor. Being the second person to step forward is infinitely easier than being the first.

  You may think that the tendency of people to follow the herd occurs only during terrible tragedies, when people are under extreme pressure. It is true that crises strengthen pack mentality, but groups regularly influence us even in ordinary and trivial situations. People are less likely to answer a ringing telephone or answer a knock on a door if others are also in a position to respond to the phone or the door. People in groups leave smaller tips in restaurants than people eating on their own. Individuals are less likely to contact authorities about a problem if many people face the same problem—a burned-out streetlight, for example.

  Some years ago, if you happened to be riding on some elevators in Seattle, Washington; Atlanta, Georgia; or Columbus, Ohio, you might have been an unwitting participant in an interesting experiment that showed how common group influences are in everyday life. Actors in elevators “accidentally” dropped some coins or pencils. If you were there, you might remember stooping to help the person pick up the items. Or, perhaps, you might remember not helping. (Most likely, you wouldn’t remember the incident at all.) When the experiment was over, 145 actors had dropped coins or pencils before audiences that totaled 4,813 people. It was a mammoth undertaking, involving 1,497 separate instances where an actor dropped coins or p
encils. What psychologists James Dabbs, Jr., and Bibb Latané were trying to find out was how often people bent down to help pick up the fallen items. When there was only one other person in the elevator with the actor, the chance that this person would help the clumsy stranger was 40 percent. In two of every five trials, in other words, an unwitting volunteer reached down to help. But as groups got larger, the likelihood that people would help began to shrink. When there were six other people in the elevator, there was still more than enough room to help pick up the items, but the chance that anyone would come to the aid of the stranger was only 15 percent.

  Imagine the scene, if you will, in five out of every six of these trials. There are six people in the elevator with the actor. The butterfingered stranger drops a bunch of coins or pencils. They fall to the floor with a clatter. And then, as the elevator counts off floor after floor after floor, not one person moves a muscle to help. It is not as though people don’t realize that someone needs help. They have to notice the stranger groping on the floor. Some people may feel uncomfortable and might silently wonder whether to get involved. But each person is surrounded by five others who are doing nothing. If the people knew they were being tested, virtually every one would instantly come to the aid of the stranger—what does it take, after all, to pick up some coins? But in the context of everyday life, where people are not thinking deliberately about how others are influencing them, going along with the group just feels like the natural thing to do.

  The result is a paradox. Large groups ought to produce more people who are willing to help. Yet they usually produce fewer Good Samaritans. Our usual approach is to credit and blame individuals.

  We conclude that those who pick up coins are helpful, while those who fail to help are callous. Our assumption is that people’s decisions are always the product of conscious, deliberate choice. The purpose of this chapter is to reinforce the idea that even when it comes to the gravest matters of life and death, there is a layer beneath the level of individual autonomy where many of the really important decisions of life take place. Like so many other situations I describe in this book, the truly devilish thing about this process is that people such as Brad Fetchet and Tiffany Alexander feel autonomous. The machinations of the hidden brain, by definition, always remain hidden.

  There is a way for us to lay bare the workings of the hidden brain in disaster situations, but it requires us to suspend our model of people as autonomous individuals. Let me show you what I mean through the example of a single employee at Keefe, Bruyette & Woods who worked on the ill-fated eighty-ninth floor. Like everyone else I interviewed at the firm, Will DeRiso was clearly above average in intelligence, social skills, and smarts. You don’t get to work at a place like Keefe, Bruyette & Woods unless you are pretty bright. With Will’s permission, however, let us stop thinking about him in the usual way for a few minutes. For the purposes of illustration, in fact, let us exaggerate the role of his hidden brain—let us imagine that he has nothing but a hidden brain. Instead of seeing Will as a smart and handsome young man with a smile that lights up a room, imagine him as a node at the center of a web. Connections radiate from him in every direction. A slender cord runs from his brain to Cold Spring Harbor, New York, where he grew up and his parents live. Another thread goes to South Bend, Indiana, where his brother the Catholic priest lives; another to New Jersey, where his sister lives, and still another to Long Island, to his other brother. If you’d mapped a diagram of Will’s life in this way before the morning of September 11, 2001, you would have seen cables running to his gym, to the golf courses and beaches he liked to frequent, and to his high school friends.

  Wherever Will went, new cables sprang up around him. Some stretched to acquaintances, others to strangers. Some were thick and strong, others slender. Some came into existence and snapped off within moments as Will passed someone he did not know on his way to work; others endured great absences and distances—the bonds of love, loyalty, and longing that make up a life. After graduating from Cold Spring Harbor high school, Will attended Notre Dame. He worked a couple of years for the Bank of America in Chicago before returning to Notre Dame to help coach the men’s lacrosse team for nine months. He joined Keefe, Bruyette & Woods on July 31, 2000, following an introduction from a former Notre Dame lacrosse player. Will got married six weeks before September 11, 2001—he and his bride, Bridget, a schoolteacher, went on a honeymoon to the Caribbean island of Saint Martin. His web of connections—some weak, some strong—continued to multiply.

  Christina Defazio and Jessica Slaven worked in the firm’s back office group on the side of the eighty-ninth floor closest to the North Tower; the cords that connected Will to them were slender because he did not know them well. Cliff Gallant worked in the firm’s insurance research group and had taught Will a lot of things—he was a good office acquaintance. Eric “Rick” Thorpe and Bradley “Brad” Vadas were close friends. They knew about Will’s propensity for anxiety; college friends used to call him “crisis boy” for blowing things out of proportion. Rick and Brad regularly played practical jokes on Will. Sitting across from Will on the eighty-ninth floor was Karol Keasler, an event coordinator and administrative assistant. She had a bubbly personality and changed her hair color regularly from blond to brown and back again. Another nearby employee was Kris Hughes, an arbitrage trader—someone who helped find common ground between stock buyers and stock sellers. Will’s job forced him to speak to countless people each day. He sold the research that people such as Cliff Gallant produced. Will needed to keep on top of what mutual fund administrators wanted to know; it was his job to supply them with a combination of what they wanted to know and what they needed to know. Like a scene from a science fiction movie, the hidden cables writhed and snaked about Will, growing and fading, but always encasing, enmeshing, embracing.

  On Monday, September 10, 2001, Will moved desks. In his new location, he happened to be the member in his group that was closest to a little corridor that led to a solid metal door. The door opened onto a hallway, and then the stairs. Employees needed a pass to unlock that door.

  On Tuesday morning, September 11, Will jumped onto a train from his home in Westchester around six-fifteen A.M., and then caught a subway from midtown Manhattan around seven. He attended the morning meeting at the firm and then drifted back to his desk. Like everyone else, he heard the explosion at eight forty-six A.M. It was more of a rumble than a boom, like an earthquake tremor, or the sound of workmen rolling something very heavy on the floor above.

  As we go through the next moments, remember that we are not thinking of Will as an autonomous human being. We are seeing him instead at the center of a complex web of interconnections, with thousands of cables tugging him in different directions. If you prefer, think of Will as a cork bobbing on an ocean, passive, acted upon by every riptide and wave and drop of foam.

  Karol Keasler yelled, “What was that?”

  Another voice screamed, “Holy shit!”

  After a moment, Kris Hughes, the arbitrage trader, exclaimed, “There was an explosion in the other building!”

  “Oh my God!” Karol Keasler’s voice was panicked. “Oh my God!”

  The explosion itself was just outside Will’s peripheral vision; the North Tower was really northwest of the South Tower. But when Will looked through a window that normally offered him a spectacular view of midtown Manhattan, he felt his stomach churn. The Empire State Building and all of midtown Manhattan had vanished. In its place was black smoke and thousands of sheets of drifting paper. It gave Will a sense of the magnitude of what had happened. The smoke and debris must have traveled fifty or a hundred yards from the other tower to so thoroughly obscure the view.

  That is a hell of an explosion, Will thought. I am glad I am not over there.

  Chaos erupted. People were jumping up. Fear leaped from one face to the next, like a contagion.

  “Calm down! Calm down!!” Kris Hughes shouted. “It is in the other building.”

  Like a v
acuum, the windows drew Will and Brad Vadas and Rick Thorpe. The horrific spectacle of the smoke and debris was irresistible. But as the tide of people drew Will toward the windows, a frantic knocking came from the door through the small hallway. It was a decisive moment.

  I can’t believe someone forgot their passkey, Will thought.

  The desperate banging escalated, a connection that demanded his attention. Will didn’t want to answer the door, but he happened to be the one closest to it. It placed an obligation on him. His connections with his friends pulled him toward the windows, but the plea from the door pulled him in the other direction. It broke him away from the tide. He went to the hallway and opened the door. As he left the main area of the floor, the connections he had to the people he left behind weakened. When he opened the door, new connections sprang out between him and the two ashen-faced women who stood outside in the hallway—Christina Defazio and Jessica Slaven.

  Like a robot, Will repeated what Kris Hughes had just said: “Calm down. Calm down. It is in the other building.”

  Defazio and Slaven were so afraid they could not speak. And then Cliff Gallant came charging up the hallway from his office on another part of the eighty-ninth floor. He had been sitting with his back to the window when his room filled with a terrifying bluish light. It blasted him right out of his chair. He ran out into the research department screaming, “Get out!”

  The bond between Will and Cliff sprang to life. There was a stairway exit right outside the door where Will was standing. Cliff Gallant and the two women made straight for it. Will glanced back once, still drawn by the weakening connections he had left behind. To his great good fortune, the architecture of the hallway that separated the door from the trading floor obscured most of the room he had left behind. He could not see his friends. And then four people from his own office, Bill Henningson, Jeff Hansen, Andrew Cullen, and Amanda McGowan come charging right at him in a pack.