This is the 2007 version. Click here for the 2017 chapter 15 table of contents.

Summary: Hostile and Helping Behavior

The topic of bystander apathy came to public attention after the horrible murder of Catherine Genovese. Thirty-eight people witnessed portions of the attack, yet it was half an hour before anybody called the police. Darley and Latané did a series of studies on the bystander apathy phenomenon. They found a diffusion of responsibility effect. When larger numbers of people witnessed a crisis, individuals were less likely to volunteer to help. Personal contact greatly increased the likelihood that people would help a person in distress.

Aggression has been studied for many decades. Contrary to old theories, frustration does not seem to be the main cause of aggression. Instead, people are aggressive when they see aggressive behavior modeled or think it is expected of them. People who witness violence in their home while growing up are far more likely to commit acts of violence later in their own relationships. Males are more prone to violent aggression than females, and testosterone (the male hormone) increases aggression. Zimbardo showed, in his famous prison study, that role-playing could elicit aggressive behavior in ordinary male volunteers.

Violence on TV has been shown to increase aggression in many laboratory studies, although the connection is harder to establish in naturalistic (real world) experiments. Violence in movies and videogames became a national concern in the United States after a spate of school shootings in the late 1990s, but other countries where such forms of entertainment are equally popular do not suffer from school shootings.

Cooperative behavior is generally more effective than competitive behavior, both in terms of performance and in terms of emotional responses to a task. Several experiments by Bryan and Test show that witnessing another person performing an act of kindness or generosity leads to an increased likelihood of similar behavior in the observer.

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