March 27, 2002. Copyright 2002. Graphic News. All rights reserved.

Embargoed for release: March 28, 2002 14:00 Eastern U.S. time. 19:00GMT

TV-watching teens may become more violent adults 

LONDON, March 27, Graphic News: One-hourÕs viewing may be the right cut-off point for adolescents watching television: more than one hour can lead to violent behaviour years later, according to new research published in the journal Science. The 18-year-long study of 707 individuals from adolescence to adulthood is believed to be the first to investigate the long-term effects of television viewing on aggressive behavior.

Jeffrey Johnson of Columbia University and the New York State Psychiatric Institute and his co-researchers found that adolescents who watched between one and three hours of television per day were more likely in their late teens and early twenties to engage in aggressive acts against other people. This was especially true for boys.

ÒOur findings suggest that, at least during early adolescence, responsible parents should avoid permitting their children watch more than one hour of television a day,Ó Johnson said. ÒThatÕs where the vast majority of the increase in risk occurs.Ó

Three to five violent acts occur in an average hour of prime-time television, and 20 to 25 violent acts occur in an average hour of childrenÕs television, according to Johnson. Thus, the amount of television the study subjects watched per day should generally reflect the amount of violence they saw, he reasoned.

The youths in the study and their mothers were interviewed four times over the course of 18 years and assigned to three categories: those who watched less than one hour of television per day, those who watched between one and three hours per day, and those who watched more than three hours per day. Families in the study were randomly sampled from two counties in northern New York State, with half being Catholic (51%) and most (91%) being white. 

Information on aggressive acts committed by the study subjects came from interviews, as well as state and federal records of arrests and charges for adult criminal behavior. The researchers grouped the violent acts according to whether they occurred around age 16, age 22, or age 30. 

An unexpected gender difference emerged as the study progressed, with the link between aggression and television watching being strongest for males during adolescence, and for females -- who watched two or more hours of television per day -- during early adulthood. While the most common types of violent behaviour for boys were assault and fighting that led to injuries, violent behaviour by young women also included robbery and threats to injure someone. 

ÒItÕs quite surprising. We certainly wouldnÕt have predicted what we found,Ó Johnson said, pointing out that the age difference might reflect the fact that adolescent girls watch less-violent television programs.

The link between watching television and behaving violently remained intact after the researchers had accounted for other factors that might be responsible for television viewing and violent behaviour -- childhood neglect, low family income, or a psychiatric disorder during adolescence. They found that 5.7 percent of the adolescents who watched less than one hour then committed aggressive acts against other people in later years. In contrast, 22.5 percent of the adolescents who watched between one and three hours a day committed aggressive acts later, as did 28.8 percent of the adolescents who watched more than three hours a day. 

Johnson and his colleagues also addressed the Òchicken and eggÓ question: does television watching cause aggression? Or, do people prone to aggression watch more television? The researchers investigated whether individuals with a history of aggressive behaviour were more likely to watch large amounts of television when they were a few years older. In fact, the authors found that was not generally the case, suggesting that heavy television watching leads to aggression, not the other way round.

Johnson emphasized that violent behaviour was just one of several unwanted effects of watching large amounts of television. ÒThe increased rate of television viewing appears to be related to an increased prevalence of obesity in the general population,Ó he said. ÒResearchers have found a wide variety of negative outcomes that are associated with extensive television viewing.Ó
/ENDS

Source: Science, the journal of the American Association for the Advancement of Science