CLEVELAND -- Seeing rejection as a common thread in school shootings across the country, CWRU psychologists undertook experiments to see if rejection in the lab produced aggression.
"Rejection does cause aggression," says Jean Twenge. "Being rejected is like getting a blow to the head. It keeps you from thinking clearly and makes you act in ways you usually would not behave. You lose self control and act impulsively," she adds.
The researchers found that college students, primed for rejection, showed a greater range of antisocial behaviors, such as increased aggression against someone who insulted them, less attempts to meet new people, less willingness to cooperate with the group or help others, or against someone they do not know.
Twenge is the lead researcher on the rejection study, "If You Can't Join Them, Beat Them: The Effects of Social Exclusion on Aggressive Behavior." Other researchers are Roy Baumeister and Dianne Tice, CWRU professors of psychology, and Tanja Stucke from the University of Giessen in Germany.
"Very little research is available on what happens to people when they feel rejected. Humans have evolved into creatures motivated to form stable, lasting relationships with others. This is deeply embedded in the culture," notes Twenge, who undertook the research while a National Institute of Health Research Fellow at CWRU during the past two years. She is now on the faculty at San Diego State University.
Pointing to the 1998 Statistical Abstract of the United States, which reports that the number of people living alone increased from 13 percent in 1960 to 25 percent in 1997, Twenge says she sees a correlation between living alone and a rise of antisocial behaviors as people marry later, move away from their nuclear families, or divorce.
Recreating rejection in the psychology lab, Twenge wanted to investigate if rejection and exclusion would lead to aggressive behavior.
Two lab experiments focused on outright rejection. The study's participants met with a group of people and were asked to write with whom they would like to collaborate from the group of people they just met. Some of the participants were told no one wanted to work with them as part of the group.
Then they played a game with a person they had not met before, and the winner was able to blast the loser with an unpleasant noise. The winner could set the noise for its intensity or duration -- similar to someone wielding a weapon, according to Twenge. The rejected group members chose a higher intensity and longer duration of noise to wage against their opponent when they lost.
In other experiments, the psychologists paired or grouped students, then had them take personality tests and write essays on a current political topic. Each participant was randomly assigned to hear one of three future predictions: that they would spend their futures alone (rejected by others), beset with misfortunes (face upsets in life but still connected socially), or belonging (the control group). In two control groups, one was accident-prone with a negative life outcome, and the other group had no feedback about accidents or information about future events.
After being told the other person had evaluated their essays (when in fact they received bogus positive or negative information about the essays), the students were asked to evaluate the other person for a job position. Students who were told they received negative feedback on the essays rated the job seeker negatively.
The researchers also tested whether rejection produced bad moods or aggression in the students. "The effect of rejection and social exclusion appeared to bypass mood and go straight to producing antisocial behavior," says Twenge. Those with predicted future outcomes of being alone gave the most negative job evaluations.
Following all the experiments, the students were debriefed and did not leave the lab until they understood that they were randomly assigned evaluations on acceptance or rejection. Rejection becomes a vicious cycle. "The logical thinking is that if you are rejected, the thing to do is to be nicer, but the subjects aren't," says Twenge.
"While our study did not prove this theory wrong, it did support the opposite conclusion," explains Twenge. "The results suggest that social exclusion led to a marked increase in aggression toward the issuer of an insult."
Twenge adds that people do not like to associate with people who are aggressive and exhibit behavior that is harmful and disruptive. "Exclusion from the group -- or even just hearing a forecast about being left out of relationships in some distant future -- appears to produce antisocial behavior," says Twenge.
"If intelligent and well-adjusted university students can respond in lab experiments with antisocial behaviors," Twenge says, "it is disturbing to imagine what might arise from a series of important rejections in actual social situations."