Mass Hysteria Is a Dangerous Form of Groupthink

Women in a group therapy session.
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Groupthink is a psychological phenomenon that occurs when a group forms a quick opinion that matches the group consensus, rather than critically evaluating the information. Mass hysteria can be seen as an extreme example of groupthink.

Groupthink seems to occur most often when a respected or persuasive leader is present, inspiring members to agree with his or her opinion. Groupthink is sometimes positive but is more often seen in a negative light, particularly in the U.S. and other countries that value individual opinion.

The History of Groupthink

Groupthink is most often associated with business, politics, and policymaking, but it also relates to the psychology of collective phobias and mass hysteria.

The term "groupthink" was coined in the early 1970s by psychologist Irving L. Janis. In 1972, Janis published his book Victims of Groupthink: A Psychological Study of Foreign-Policy Decisions and Fiascoes.

Janis defines "groupthink" as "a psychological drive for consensus at any cost that suppresses dissent and appraisal of alternatives in cohesive decision-making groups."

Janis identified eight symptoms of groupthink, which included illusions of invulnerability, self-censorship, and direct pressure.

Janis blamed groupthink for such political "fiascos" as the Bay of Pigs invasion, the failure to prepare for the attack on Pearl Harbor, the escalation of the Vietnam War, and the Watergate coverup.

Scholars have gone on to blame such later events as the decision to launch the doomed space shuttle Challenger, the Iran-Contra affair, and the Enron scandal on groupthink.

Groupthink and Mass Hysteria

It's believed that groupthink increases as group cohesiveness increases. This may help to explain the psychological phenomenon of mass hysteria.

Mass hysteria is also known as epidemic hysteria, mass psychogenic illness, and mass sociogenic illness. According to a 1997 review of research by The Johns Hopkins University School of Hygiene and Public Health, mass hysteria is "a constellation of symptoms suggestive of organic illness, but without an identifiable cause, that occurs between two or more people who share beliefs related to those symptoms." It's "seen as a social phenomenon involving otherwise healthy people."

Some psychologists believe mass hysteria is a form of groupthink. In cases of mass hysteria, the group members all develop a common fear that often spirals into a panic.

The group members feed off each other's emotional reactions, causing the panic to escalate.

The Salem witch trials and the panic over the War of the Worlds radio broadcast can be viewed as examples of mass hysteria related to groupthink.

A widely publicized case of possible mass hysteria occurred in 2011 in upstate New York when teenage girls from the same high school began exhibiting an unexplained twitching disorder.

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Article Sources

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  • Classics of Organization Theory. Chapter 15, "Groupthink: The Desperate Drive for Consensus at Any Cost," Irving L. Janis. 
  • Victims of groupthink: A psychological study of foreign-policy decisions and fiascoes. Irving L. Janis.