Stocksy

It’s because infants understand what other humans are drawn to, and they copy their behavior and learn from it. Even as adults, our actions continue to be driven — often unconsciously — by others.

Shortly before my daughter Livia turned one, a friend came to visit. Enthusiastically, he told me about the doljanchi celebration he had attended. Doljanchi is a Korean tradition that takes place at a child’s first birthday. The best part, he said, was the fortune-telling ritual. The baby is placed in front of an assortment of objects and is encouraged to choose one. The selection is believed to forecast her future; if she picks up a banana, she will never go hungry; a book, she is destined for academia; a silver coin, wealth, and so on.

I was intrigued. That evening, I placed Livia in front of various items: a stethoscope (would she become a doctor?), a stuffed dog (vet?), a plant (Greenpeace activist?), pastry (chef?) and a colorful model of the brain (neuroscientist?). Livia took her time, inspected all the options closely — and then went straight for the iPhone that I had happened to place at the corner of the table.

I shouldn’t have been surprised. She was obsessed with that device. She would skillfully roll herself from one side of the room to the other to grab hold of it. Such a maneuver would make sense if she then checked her email or updated her Facebook status. That was not her intention. Whenever she got hold of it, she would insert it into her mouth and attempt to chew. Although eating the iPhone proved unsuccessful, she was not discouraged. Time and time again, she would reach for it even if edible items were in sight. It was not the noise and lights that intrigued her; she had other bright musical toys that she did not desire as much. The iPhone was the item she wanted because from the day she was born, she’d observed her parents constantly interacting with it with great interest. Livia’s fondness for iPhones tells us something important about how our brain works.

It suggests we’re born with an automatic predisposition to learn from those around us. We learn almost everything — from what item is most valuable to how to peel an orange — from observing other people’s behavior. We imitate, assimilate and adopt; and we do this often without awareness. The advantage of this is that we need not learn only from our own limited experiences but can rely on that of others. This means we can learn quickly, rather than from the slow process of trial and error. The problem, however, is that our needs are not always equivalent to those of others. Take Livia, for example. Livia would have been better off choosing the pastry that she could chew on or the stuffed dog she could play with. But she did not want the things that fit her needs; she wanted the one that fit mine: the phone.

Following someone else’s choices can be harmless, but it can also be life-threatening. For example, 10 percent of kidney donations in the US go unused every year. When a donation is declined by one patient — whether it’s due to their specific medical condition or religious beliefs — the next patient on the list is informed the organ was declined but not told the reason. That patient then frequently assumes the organ is faulty and passes up a potentially lifesaving operation — as does the next patient, and the next.

This concern is magnified today because people frequently use online ratings to make decisions. We choose where to vacation and which physician to use based on ratings. Ratings are the new guide for living, but how good a guide are they? We assume online rankings reflect the opinions of many independent users. But when you rate a restaurant on Yelp or a product on Amazon, you’re not starting with a blank slate; you are presented with existing ratings, which influence your own. In one study, Shawn Taylor and colleagues found if you manipulate the first review to be glowing, the likelihood of other positive reviews increases by 32 percent and the final rating is enhanced by 25 percent. This means the difference between a mediocrely rated physician or hotel and a phenomenally rated one can sometimes be attributed to the first person who logged on and registered their opinion.

Yet almost all of us say we are less likely to be influenced by others than the next person. Take the experiment conducted by Caroline Charpentier and I. We asked 100 volunteers to come into our lab at the center of London after fasting all day to rate 80 food items, from baked beans to apples and wasabi peas. They then made multiple selections from the items, which we’d give them at the end of the study. Just before they made their choices, we presented them with what other students had selected. At the end of the study, we asked if they thought they’d been influenced by the other participants. One student said, “I was interested and occasionally surprised to see what others chose but my preferences stayed the same”; another said, “It was their choice and it did not influence me in making my own choices.”

Like most of our participants, these two were wrong. Looking at the first participant’s behavior, we found 20 percent of the time she picked a food item she initially said she didn’t like at all (such as cherry tomatoes) after learning others had chosen it (the second student did the same 10 percent of the time). When people perceive other people’s choices, their brain automatically encodes added utility to those selected options in regions that are important for signaling value. This is because our brain operates according to the role that what is desired by others is likely valuable. Later, when it’s time to make a choice, we unconsciously retrieve these value signals and use them to make a decision.

Another study that my colleagues and I conducted revealed that other people’s opinions alter not only our preferences but also how memories are registered in the brain. In this experiment, which was led by Micah Edelson, we invited groups of five people to our lab to watch a documentary. We then quizzed them about it (for example, we asked “what color was the policeman’s hat?”). A few days later, we invited them back to record their brain activity in an MRI scanner while they completed the same quiz. This time, before they gave their answers, they were shown the responses of the other people in their group. Unbeknownst to our volunteers, in some instances we presented them with false answers.

Astonishingly, 70 percent of the time our volunteers went along with these incorrect answers. A week later, we invited everyone back to our lab and told them the information we gave them before was randomly generated and asked them to take the quiz one last time. About half the time, our volunteers corrected the false memories we induced in them, but about half the time they held on to these false beliefs.

An almond-shaped structure deep in the brain — the amygdala — predicted whether false beliefs would be resistant to change. The amygdala is involved in producing emotional arousal and processing social information. When the amygdala was activated at the same time with a nearby region that is essential for creating memories — the hippocampus — people’s memories of the film were changed. When participants later discovered we’d provided them with fake recollections, those with highly active frontal lobes were able to recover their original memory of the movie. But this didn’t work if their amygdala reacted very strongly to other people’s opinions.

The first takeaway from this research is we need to be careful when we depend on other’s judgements and actions to guide our own. Many times, influence happens under the radar, but we can try to become more aware that it’s going on and be careful not to trade our own unique tastes for those of another.

The second takeaway is we need to be mindful that when our opinions and decisions are observed by others, they can make a difference. Whether it’s accepting a job offer, rejecting a romantic partner or passing on an organ donation, all of these actions can change others’ perceptions and decisions. In fact, in describing the documentary experiment that my colleagues and I carried out, I failed to mention one detail. Our volunteers would discard their own correct memories and adopt the false ones of others, as long as everyone in the group — unanimously — supported the wrong answer. But if one other person provided the correct judgment, the volunteers stuck to their original beliefs. In other words, even in a swarm, one divergent voice can cause others to act independently. You are influenced by others, but do not be fooled — others are also influenced by you. That’s why your actions and choices matter not only for your own life, but for the behavior of those around you.

Excerpted with permission from the new book The Influential Mind: What the Brain Reveals About Our Power to Change Others by Tali Sharot. Published by Henry Holt and Co. Copyright © 2017 Tali Sharot.