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Summary: Social Influences

Many of the early studies in social psychology involve group influences on individuals. Allport (1935) proposed that conformity followed a pattern called a j-curve, with large deviations less common than small deviations.

Sherif (1936) found that people in a group arrived at a group norm for judging the (illusary) movement of a point of light in a darkened room. Asch found that people could be pressured into making an obviously incorrect judgment, if other people did so first.

The Asch experiment inspired Stanley Milgram to study a more important form of conformity. In his famous obedience study, participants were led to administer what they thought were shocks to a helpless victim. To the surprise of psychiatrists, most people obeyed instructions that seemed to be harming another person.

Philip Zimbardo, a high school classmate of Milgram's, did similar research in the Stanford Prison Experiment. Volunteer participants were randomly assigned to the roles of prison guards or inmates. The guards became abusice, and the experiment was aborted because it was causing too much distress.

Twenty-first Century critics see both Milgram and Zimbardo as showing the effects of "involved engagement." When people are recruited into what they regard as a worthy cause, they can be persuaded to do things they would not normally do. Milgram and Zimbardo did the same thing; they justified their own cruelty as part of worthy scientific research.

Persuasion is an attempt at attitude change. After World War II, Hovland outlined three variables likely to affect persuasion: characteristics of the communicator, the communication, and the situation. Source degradation occurs when an act of persuasion is discounted because the source is portrayed as unrealiable.

Hovland also discovered the sleeper effect: a tendency of people to forget the source of information. As a result, information from an untrustworthy source can be influential, after time passes and a person forgets where they encountered the information.

Petty and Cacioppo introduced the Elaboration Likelihood Model (ELM) in 1986. They found that positive emotions associated with ads (because of puppies, good looking people, celebrity endorsers, etc.) could improve ratings of a product as long as people did not think much about the message. If people were led to ponder the logic or arguments of a message consciously, those factors were ineffective.

Media effects, the influence of mass media in changing peoples opinions or attitudes, have interested pundits and cultural onlookers since around 1900 when movies and phonographs became available. Research started in the 1960s as television became pervasive, and people worried about effects of violence on TV.

Research never did establish large effects of TV upon violent behavior, but the 1960 presidential elections in the U.S. showed that TV could influence voters. By 1968, Richard Nixon was willing to appear on the comedy program Laugh-In, and he believed it won him the election.

Videogames inspired worries similar to earlier concerns about TV and violence, when "first person shooters" became popular. School shootings by teenage boys were blamed on videogames by some observers, although such shootings did not occur in Japan where such videogames were also very popular.

Media contagion effects may have been responsible for the high number of school shootings in the 2000s. Numerous studies suggested later school shooters were imitating earlier acts and seeking similar publicity.

In the late 1990s, when social media consisted mostly of chat rooms, several researchers raised the possibility that internet use was leading to loneliness and social isolation. Others said the correlation was due to self-selection, with lonely or bored people seeking out contact on the internet, rather than internet usage causing loneliness.

Social comparison could be a factor, if social media do produce negative moods. Users might feel inferior compared to the "highlight reels" of other people's life events typically displayed on platforms like Facebook.

Helpful behavior can be encouraged by examples, as shown by studies from the 1960s and 1970s. When people observe others undertaking helpful behavior, they are more likely to do so themselves.

Crowdsourcing is a form of pro-social cooperation enabled by the internet. Groups of strangers cooperate to fund causes they regard as worthy, even if they do not know the person receiving support.

Internet-related services in general are becoming pervasive and important. They are now studied by everybody interested in politics, economics, or culture, not just psychologists.

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