The term “mob mentality” is used to refer to unique behavioral characteristics which emerge when people are in large groups. It is sometimes used disparagingly, as the term “mob” typically conjures up an image of a disorganized, aggressive, panicked group of people. Social psychologists who study group behavior tend to prefer terms like “herd behavior” or “crowd hysteria.” The study of mob mentality is quite fascinating, and it is used to analyze situations which range from evacuations gone awry to the moment when demonstrations turn violent.

The larger study of herd behavior considers groups of all animals, not just humans. People have been observing group behavior of flocks, herds, gaggles, pods, kindles, and other assortments of animals for thousands of years, but it was not until the early twentieth century that observers started applying scientific theories about crowd behavior to humans. Several books published in the teens discussed mob mentality, along with various ways to combat it.

When used in a pejorative sense, the term implies a group of people which has gotten out of control. For example, in a news story about a store sale at which people were trampled, the journalist might use “mob mentality” to describe the selfish behavior of the people who attended the sale. Such stories illustrate the desperate actions which people will involve themselves in during a period of resource competition; people may mob trucks with relief supplies, trample each other at big box stores, or riot in the streets in response to resource scarcity or a perceived scarcity.

However, “mob mentality” is about more than just crowds which have gotten out of control. The field of psychology is very interested in the ways in which human behavior change in response to new social situations. People behave very differently in small groups of individuals than they do in big crowds, for example, and their behavior in crowds is affected by a wide variety of factors.

The study of group behavior can analyze situations to see where, when, and why they went wrong. Stock market crashes, for example, can be precipitated by mob mentality, as people start to panic in response to fluctuating markets. The evacuation of the Titanic, in which a small fraction of the available lifeboat space was utilized, is another great example of mob mentality, illustrating the need for organized evacuation plans and drills so that people know what to do in an emergency.

The study of crowds has also been used to study grim topics like the rise of antisemitism in Germany under Hitler, the riots between Muslims and Hindus which broke out when India was partitioned, and the genocide which took place in Rwanda in 1994. Psychologists hope that by studying mob mentality and crowd behavior, they can prevent such events from recurring.