if he hadn ’t watched Taxi Driver. After all, millions of people saw the movie
without reacting aggressively. Although most of us find it difficult not to see
a link between viewing aggression and performing aggression in these exam-
ples, these incidents supply only weak evidence for this connection.
Fortunately, we don ’t have to rely on this circumstantial evidence.
Researchers have provided a wealth of experimental data concerning the impact
of viewing aggression on performing aggression. The vast majority of these stud-
ies find the causal link irrefutable: Viewing aggression increases the likelihood ofacting aggressively, especially over a short time span (Anderson & Bushman,
2002b; Bushman & Huesmann, 2001; Friedrich-Cofer & Huston, 1986;
Geen, 1998; Paik & Comstock, 1994; Smith & Donnerstein, 1998; Wood,Wong, & Chachere, 1991). Most of the data come from controlled laboratory
experiments. Typically, participants watch a segment from either a violent or an
arousing but nonviolent program or movie. Then they are given the opportunityto act aggressively against another person, often by administering electric shocks
or loud noise they believe will hurt the other person. In almost all cases, partici-
pants who watch the violence act more aggressively than those who see thenonviolent clip.
Although impressive, this research also contains some limitations. The
effects typically are short-lived, and the opportunity to hurt another personprovided by the experimenter is unique. Therefore, it is reasonable to wonder
how much these studies tell us about the impact of aggressive movies and
television shows in real-life situations.
In response to this question, several investigators have conducted long-
term field studies to gauge the impact of exposure to violence and aggressivebehavior outside the laboratory (Eron, 1987; McCarthy, Langner, Gersten,
Eisenberg, & Orzeck, 1975; Singer & Singer, 1981). In each case the re-
searchers use the amount and kind of television children watched at one point
in their lives to predict how aggressive the children would be at a later date.Like the laboratory studies, these investigations find significant evidence
indicating that watching a lot of aggressive television leads to more aggres-
sion in children and adults.
One team of researchers began their investigation by determining
how much television a group of 8-year-old children watched (Eron, 1987;Huesmann, Eron, Dubow, & Seebauer, 1987; Lefkowitz, Eron, Walder, &Huesmann, 1977). They then waited 22 years before measuring aggressive
behavior in these same individuals at age 30. The researchers found a signi-
ficant relationship between the am ount of television the participants
watched as children and the likelihood that they would have been convicted
for criminal behavior by age 30. As shown in Figure 14.5, the seriousness
of the criminal act was directly related to the amount of televisionwatched. The more TV the 8-year-old had watched, the more serious the
adult crime.
Another investigation measured the amount of television boys and girls
watched at age 14 and incidences of aggression over the next 8 years(Johnson, Cohen, Smailes, Kasen, & Brook, 2002). As shown in Figure 14.6,
the percentages of men and women who engaged in some act of aggressionObservational Learning of Aggression 391