A new study linking increased aggressive behavior to adolescent television watching is adding weight to recommendations that parents strictly limit how much time young people spend in front of the tube.
“The evidence has gotten to the point where it’s overwhelming” said Jeffrey G. Johnson of Columbia University, lead author of a study that found watching more than one hour of TV daily is followed by increases in the rate of assaults, fights, robberies, and other aggressive acts in later years.
Johnson’s research team studied more than 700 people for 17 years. The increase in aggressive behavior with more TV watched held true both for people who had previous violent incidents and for those who had not had shown earlier aggression, they found. That means the findings are not merely the result of people already prone to violence being more avid viewers.
“Our findings suggest that, at least during early adolescence, responsible parents should avoid permitting their children to watch more than one hour of television a day,” said Johnson, who is also affiliated with the New York State Psychiatric Institute.
While other studies have linked watching violent television to later aggressive behavior, Johnson said this is the first to investigate the total amount of time individuals spent watching and to follow those people over many years.
The study appeared in the March 29 issue of Science Magazine.
Among youths who watched less than an hour of television daily at age 14, just 5.7 percent were involved in aggressive acts by the ages of 16 to 22, the study found.
But for those who watched between one and three hours the aggression rate jumped to 22.5 percent, and the rate was 28.8 percent for those who watched three hours or more, the study found.
The effect was most pronounced for boys, with rates of 8.9 percent committing aggressive acts for those who watched less than an hour of TV at age 14, 32.5 percent for one to three hours, and 45.2 percent for those watching more than three hours of television. For girls, the rates were 2.3 percent, 11.8 percent, and 12.7 percent.
Dennis Wharton, a spokesman for the National Association of Broadcasters, said he has not seen the study but found the results surprising. He cited recent research that suggests violence on TV has fallen over the past two years.