NEW YORK (Reuters Health) - Children who get heavy doses of media violence may be at greater risk of violent behavior as teenagers -- even when a range of other influences is considered, according to a new study.
The findings, the authors say, add to evidence that violence-packed TV shows, movies and video games can affect some children's behavior.
"Even in conjunction with other factors, our research shows that media violence does enhance violent behavior," lead researcher Paul Boxer, of Rutgers University in Newark, New Jersey, said in a written statement.
"On average, adolescents who were not exposed to violent media are not as prone to violent behavior."
The findings, reported in an early online edition of the Journal of Youth and Adolescence, come from interviews with 820 teenagers and surveys of their parents and teachers. Just over half of the teens were recruited from Michigan high schools, while the rest were in juvenile detention centers. The subjects were evenly mixed in the number of males and females, and the number of minorities and non-minorities.
Boxer's team asked the teenagers about their favorite TV shows, movies and video games going back to the age of 7, and then created "scores" for each participant's total violent-media exposure.
The researchers also collected information on a number of other factors that can affect children's risk of violent or aggressive behavior including academic difficulties, a history of psychological and emotional problems and exposure to real-life violence.
The investigators found that even with these other factors considered, heavy doses of media violence were related to a higher risk of violent behavior and general aggression in adolescence. Even teens at low risk of violence overall seemed to be vulnerable to the influence of media violence.
Based on these and past findings, "there currently can be very little doubt that exposure to violence in the media has a consistent and substantial impact on aggressive behavior," Boxer and his colleagues conclude.
The researchers are currently studying ways in which media violence may affect preschoolers' behavior. Young children, Boxer noted, tend to mimic the behavior they see, but are not yet able to tell reality from fantasy, or right from wrong.
By understanding the mechanisms that influence children's development, "researchers can try to learn how to intervene in potentially aggressive or antisocial behaviors, and effect change at a very young age," he adds.
SOURCE: Journal of Youth and Adolescence, February 2009.