Deindividuation (Social Psychology Definition + Examples))

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Did you know that there has been at least one death caused by “hazing” every year since 1972? For many fraternities and sororities, hazing is a ritual. It often involves copious amounts of drinking, rigorous physical challenges, and simply disgusting activities. 

How does this happen so often? You can’t imagine any of the individuals involved in the hazing to cause someone’s death, or for any of the victims to drink so much alcohol on their own. Individuals don’t haze themselves. 

But being in a group, especially a fraternity or sorority, can seriously change a person’s behavior. In order to allow many hazing activities to happen, there has to be some level of deindividualization.

What Is Deindividualization?

Deindividualization is the process in which an individual loses their “sense of self” when they’re in a group. They identify with the group’s mentality, even if it would normally clash with their own. The group’s actions, feelings, and beliefs become the individual’s, and they begin to act in accordance. 

Deindividualization may lead people to do or say things that they wouldn’t do outside of the group. It can be downright dangerous in fraternities, sororities, religious organizations, or at political protests. But not all deindividualization is unhealthy or violent. 

Staying aware of deindividualization, and how it may affect your thinking, can help you maintain a strong sense of self even within a large crowd. 

Why Does Deindividuation Work?  

There are a few reasons why individuals lose their sense of self when surrounded by a large group. 

Diffusion of responsibility (The Bystander Effect) 

Who is responsible for stopping the violent behavior of a large group? In a large group, who is responsible for stepping in and helping someone who may be in distress? One could argue that everyone has this responsibility. So why should you act? 

The diffusion of responsibility is a form of attribution in which other people assume that someone else should be responsible for taking action. Maybe you think the guy next to you is more responsible for acting because he is bigger and stronger. Or the person closest to two people fighting should be responsible for breaking it up. The more people you see in a crowd, the more people you can give responsibility to. 


When you’re standing alone, people can only identify you as who you are. But when you’re in a crowd, you may feel that you’ve lost that option. You are instead identified as someone in the crowd. With anonymity and without responsibility, you may act in ways that you wouldn’t if you knew you were being held responsible. 


When people don’t know what to say or what to do, they look to others. In or out of a crowd, they allow others to “fill in the blanks.” This suggestibility may lead you to remember things incorrectly, change your opinion of things, or act in a certain way. In crowds, you may witness many people directly or indirectly “suggesting” that you believe something or act in a certain way. It’s hard not to believe that something is right or wrong when people are suggesting it to be so. 

History of Deindividualization 

These ideas are not new to the world of social psychology. In 1895, a French psychologist named Gustave Le Bon published The Crowd. The book suggested that when people form a crowd, the ideas of the crowd take over. Like a contagious virus, everyone gets swept up. He also suggested that crowd mentality is intellectually weak, emotional, and brings people to a more primitive level.

Le Bon’s work inspired many psychologists to build on these ideas, but it wasn’t until 1952 that the term “deindividualization” was used. Psychologists Leon Festinger, Albert Pepitone, and Theodore Newcomb are often credited as the first to coin the term “deindividualization.” They expanded on Le Bon’s ideas, setting the foundation for the idea of deindividualization into the concept as we know it today. 

In 1969, Philip Zimbardo suggested that “normally inhibited behavior” wasn’t just something that resulted in hazing deaths or political violence. He expanded the ideas of deindividualization to include more positive examples, which I’ll get to in a minute. Of course, Zimbardo isn’t exactly tied to positive results himself. You might remember that Zimbardo was behind the entire demonstration. 

As with all ideas in social psychology, researchers have continued to define and develop the idea of deindividualization to fit in with the ever-changing world. 

Examples of Positive Deindividualization 

I started out this video talking about fraternities. Not all examples of deindividualization involve hazing, violence, or Greek letters. You may have experienced some of these examples yourself! 

Marathon Running

Take running a marathon. Not every runner in the race could (or would) run 26.2 miles at one time. But in a big crowd, everyone’s adrenaline is pumping and the runners are motivated to make it to the finish line. It may be “easier” to put your doubts and fears away and just keep running with the pack. 


The same could be said for a long day of volunteering. You might not be inclined to plant a few dozen trees out in the woods or deliver a dozen meals to the homeless if you’re alone. But when you’re in a group, the work doesn’t seem like work. It’s more motivating to go with a group of people who are committed to braving the cold or working all day to help others. 

Religious Organizations

Then, of course, you might see deindividualization happen in religious organizations. You might go feed the hungry with your religious group. Or, in extreme cases, you might go to war on behalf of your religious ideals. It’s easy to get swept up in more extreme beliefs and actions when you have a group of followers justifying what you are doing. 

How Can Deindividuation Be Prevented? 

Deindividualization doesn’t just happen in cults or fraternities. It doesn’t just lead to bad things. But the more you stay aware of this process, the easier it will be to step aside when things go against your individual morals. Stay mindful, stay aware, and stay grounded in what you believe in, even if you’re in a crowd of “deindividualized” people who may be acting in a different way.

Reference this article:

Practical Psychology. (2019, December). Deindividuation (Social Psychology Definition + Examples)). Retrieved from

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