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Inoculation and Forewarning

In some cases, authorities want to prevent persuasion. After the Korean War with its reports of brainwashing, psychologists tried to figure out how to build up resistance to unwanted persuasion. William McGuire and colleagues advocated a technique called inoculation (McGuire and Papageorgis, 1961). To inoculate a person against persuasion, that person is exposed to weak attacks on a favored position. The attacks must be weak so they do not actually change attitudes, but the person is encouraged to fight them off and thereby learn to resist attacks. McGuire and colleagues were able to show that, in experimental situations, inoculation approaches were more powerful than simply telling a person they were right and should ignore attempts at persuasion.

What is "inoculation"?

Similar to inoculation is forewarning: letting a person know ahead of time that a favored attitude will be challenged. This allows a person to rally defenses or prepare to resist the message. If a person is forewarned that a salesperson will call with a misleading offer, the person is unlikely to find the salesperson persuasive.

What is forewarning? How did Freedman and Sears document a forewarning effect with teenagers?

Freedman and Sears (1965) documented a forewarning effect. They measured the persuasiveness of a lecture given to teenagers, arguing that "Teenagers should not be allowed to drive." One group of teenagers was warned about the topic ten minutes ahead of time; the other was simply given the lecture. The group warned ahead of time showed less attitude change. Presumably they disagreed with the message, and when they had more time to prepare for it, they were less convinced by it. Petty and Cacioppo (1977) verified that a delay between a warning and the delivery of a message encouraged people to generate more arguments against the message.

How were the techniques of inoculation and forewarning used in anti-drug programs with children?

These principles were applied in anti-drug programs for children in the United States, such as Project D.A.R.E. (Drug Abuse Resistance Education). The objective was to prevent children from being persuaded to use drugs. To inoculate and forewarn them, children participated in skits where one child (playing the role of a drug pusher) asked another child to take drugs. The second child refused. This little drama was acted out again and again, in many variations. Group pressure was also used. Children were assembled in an auditorium and asked, "What will you do if someone offers you drugs?" and they all yelled back, "Say No!" In such programs, the children were challenged, but only symbolically, and they rehearsed a defense against attack.

In addition to inoculation, anti-drug programs used other persuasion tactics. Authority figures such as police officers delivered the anti-drug message. Students were asked to wear colored ribbons as symbols of their commitment to anti-drug attitudes, and they were rewarded with T-shirts and bumper stickers after the program was over.

What did Petty say about project D.A.R.E.? What was happening a few years later?

Petty (co-author of the Elaboration Likelihood Model and a leading researcher on persuasion and attitude change) told an interviewer in the early 1990s that Project D.A.R.E. proved that social psychology principles from the laboratory could be used successfully in real life settings involving important problems (Krupat, 1994). However, within a few years, the D.A.R.E. program was criticized as ineffective. Teenage drug use, which had fallen since the 1970s, rose dramatically in the early 1990s, during years when children who had received D.A.R.E. programs in grade school became teenagers. D.A.R.E. might end up illustrating the difficulty, rather than the ease, of moving from laboratory studies to the real world. It is even possible that early anti-drug programs aimed at young children inoculate and forewarn students against later anti-drug messages. By high school, when the real threat is more likely to occur, most students have "heard it all before."

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