What Is the 'Bystander Effect' and How Do People Overcome It?

This story appeared in the June 2020 issue as "Action!" Subscribe to Discover magazine for more stories like this.

On April 9, 2017, three security officers from the Chicago Department of Aviation forcibly removed David Dao from an overbooked United Airlines flight. Dao, a 69-year-old doctor, was dragged down the plane’s aisle after he refused to give up his seat. In the process, his head hit an armrest and he was knocked unconscious.

The passengers clearly recognized what was occurring: Many took out their phones and filmed the scene and later expressed their outrage loudly on social media. Yet at the time, only one woman said anything, yelling out, “What are you doing?” No one confronted the officers or intervened to prevent what was clearly inappropriate behavior.

At some level, this is hardly surprising. Numerous studies have shown that we are less likely to intervene when other people are present. We assume that others will do something, and we don’t have to. Psychologists call this phenomenon the bystander effect.

However, this is not a hard-and-fast rule; sometimes people in groups are able to break out of the bystander role. But who are these people, and what makes them different from the rest of us?

Psychologists call those who display moral courage and choose to do something rather than watch in silence moral rebels. These people stand up against the status quo when they feel inaction will compromise their values, even in the face of potentially negative social consequences. The traits that these people have in common range from their individual skill sets to their personalities — and might even be reflected at a neurological level.

If you act, will it matter? Asking this question might be the difference between standing up or standing by. It also helps explain why people with specialized training are more likely to spring into action in an emergency. Doctors, nurses, soldiers or volunteer firefighters may feel more responsible to act in some scenarios — and research shows they usually do.

In one study, researchers recruited students from both a nursing program and a general education program to take what they were told was a simple questionnaire. Half of the students were placed in a room alone to work on their questionnaire; the others were in a room with another student (who was actually the researchers’ accomplice). As they were working, they heard a man fall from a ladder outside the room and scream out in pain.

Education students who were alone were much more likely to help than those who were with another person. But the percentage of nursing students who helped was the same whether they were alone or not. This doesn’t mean that nursing students are nicer people — it reflects the fact that they knew what to do, and therefore felt a greater responsibility to act.

Research has also shown that people feel more responsibility if they are in a position of authority. In some instances, the person with the specialized knowledge isn’t the person with authority. Even so, they may take charge.

During my senior year of college, I was sitting in a classroom on the fourth floor of a building when the room suddenly started swaying back and forth. The 1989 Loma Prieta earthquake had just struck Northern California. The students all turned to the authority — the professor — to figure out what to do.

Her response was not what we had expected: She grabbed the edge of the table and yelled, “I’m from New York!” Her statement clearly indicated that she had no idea what to do.

Another student then yelled, “I’m from California,” establishing his credibility in this emergency. Then he said, “Get under the table.”

Besides wielding expertise in certain situations, moral rebels tend to have high self-esteem and feel confident about their own judgment, values and ability. But moral rebels don’t just feel confident that they are right — they believe their actions will make a difference.

To better understand the specific personality traits that underpin moral courage, Tammy Sonnentag at Xavier University and Mark Barnett at Kansas State University studied the characteristics of over 200 seventh and eighth graders. They first asked the students to rate their own willingness to stand up to others and say or do the right thing in the face of social pressure to stay silent and go along with the crowd.

Next, they asked all students in each grade, and one teacher, to rate the tendency of each student to adhere to his or her moral beliefs and values in the face of pressures not to do so. That way, researchers could assess whether students who self-identified as moral rebels actually did behave in ways that were visible to others and weren’t just imagining themselves to be courageous.

The researchers found a high level of agreement between was a moral rebel. Those who fit the bill also tended to possess particular personality traits: They generally felt good about themselves, rating themselves highly on statements such as, “I feel I have a number of good qualities” and “I can do things as well as most other people.” They were also confident about their ability to accomplish their goals and to stand up to social pressure, agreeing with statements like, “I will be able to successfully overcome many challenges” and “I follow my own ideas even when pressured by a group to change them.”

But these students didn’t just feel confident and good about themselves. They also believed that their own views were superior to those of others, and thus that they had a social responsibility to share those beliefs. They agreed with statements like, “I feel a social obligation to voice my opinion” and “If everyone saw things the way that I do, the world would be a better place.” This belief in the correctness of their views helped them speak up when other students tended to stay quiet.

And, perhaps most important, these students were reportedly less concerned about fitting in with the crowd. That means when they have to choose between fitting in and doing the right thing, they will probably choose to do what’s right.

One drawback with studies such as this one is that they rely on self-reporting about intentions. What we really want to know is whether certain personality variables actually predict helping behavior in the real world. After all, many of us, maybe even most of us, imagine that we’d step up in an emergency, but we often don’t live up to our good intentions.

To get around this problem, researchers at Columbia University looked at the personality traits of a select group of people who helped others in a real-world emergency: the Holocaust. Although acting in this situation clearly required physical courage, it also required moral courage to take action when most others did nothing.

The researchers compared personality traits among three different groups of adults: those who had rescued at least one Jewish person during the Holocaust, those who had provided no help and those who left Europe before the start of World War II.

People who risked their own lives to help Jews differed in several ways from those who did not. They scored higher on independence and perceived control, indicating that they were willing to stick with their own beliefs even if others disagreed and that they felt their life outcomes were due to their own efforts and choices. They also scored higher on risk-taking and were comfortable with tasks that involved danger. This combination of attributes appears to have given them the confidence to show courage. But they had other important traits that have to do with concern about others: altruism, empathy and social responsibility. These traits would have driven them to feel compassion and a need to act, even at great personal risk.

The Holocaust, of course, was a far cry from the more mundane situations in which most of us find ourselves pondering whether to act. To investigate this kind of everyday situation, researchers at Hannover Medical School in Germany asked a local hospital for the names of people who had administered first aid to car accident victims. They contacted these people and asked them to complete personality questionnaires. Thirty-four people agreed to do so. The researchers also asked people who had seen the accident but had not provided help to complete the same questionnaire.

Those who had provided help scored higher on perceived control, empathy and social responsibility — exactly the same characteristics as those who had rescued Jews in Nazi Germany. All of these studies together paint a picture of a moral rebel: someone who is confident, independent and altruistic, with high self-esteem and a strong sense of social responsibility.

Moral rebels certainly have a tendency toward certain traits, but are their brains anatomically different from the rest of the population?

In 2014, a Georgetown University study examined differences in patterns of brain activity in 19 people who had engaged in a quite extraordinary act of generosity: donating a kidney to a total stranger. The donors’ amygdala — a part of the brain that processes emotions — was found to be 8 percent larger than it is in most people, and it also showed greater activity.

But we need to be cautious about interpreting this finding. It’s possible that these kidney donors were born with larger and more active amygdala, which caused them to care more about other people. It’s also possible, though, that engaging in this type of extreme altruism could actively rewire the brain. Regardless of the causal connection, it does appear that extraordinary altruists show distinct patterns of neural activity that are associated with a greater responsiveness to emotion. People who demonstrate this type of selfless giving may experience the costs of helping differently from the rest of us. Not helping may actually make them feel worse.

There is also evidence that people who engage in extraordinary acts of altruism show distinct patterns of neurological responses to two types of painful experiences: experiencing pain themselves and watching someone else experience pain.

In one study, researchers measured empathy in nearly 60 people, half of whom had donated a kidney to a stranger and half of whom had not. Each participant was then paired with a stranger to complete a series of trials. In one set of trials, participants watched their partner receive painful pressure to the right thumbnail while researchers recorded their brain activity using fMRI imaging. In another set, the participants themselves received the thumbnail pressure, again while their brain activity was assessed. Researchers then compared the two sets of brain activity.

For most of us, experiencing pain ourselves feels far worse than watching a stranger experience pain. But the brains of those who had demonstrated extraordinary altruism responded in almost the same way to their own pain as to that of others, suggesting that they were experiencing someone else’s pain as though it were their own. For people who feel others’ pain so deeply, the choice to donate a kidney to a stranger may therefore make sense: If they feel pain themselves from knowing that someone else is in pain, helping that person would make them feel better.

Donating a kidney to a stranger may be an extreme example. Few people will think less of you for not choosing to do so, and it does have physical risks. But the discoveries of these studies have much broader implications, since the ability to feel empathy is an important characteristic of those who are willing to face social consequences for doing the right thing.

Adapted excerpt from Why We Act: Turning Bystanders Into Moral Rebels by Catherine A. Sanderson, published by Harvard University Press. Copyright © 2020 by Catherine A. Sanderson. Used by permission. All rights reserved.

Catherine A. Sanderson is the Manwell Family Professor in Life Sciences at Amherst College, where she has been researching social norms for the past 20 years. She is also the author of The Positive Shift: Mastering Mindset To Improve Happiness, Health, And Longevity.