BETHESDA, Md., Oct. 19 (UPI) -- Teens who watch violent films, TV or video games may not only get desensitized, but U.S. researchers say the violence may promote aggressive behavior.
Dr. Jordan Grafman, senior investigator at the National Institute of Neurological Disorders and Stroke, National Institutes of Health, in Bethesda, Md., and colleagues recruited 22 boys ages 14-17, who watched short, 4-second clips of violent scenes from 60 videos, arranged randomly in three lots of 20 clips.
The degree of violence and aggression in each scene was low, mild or moderate, but there were no extreme scenes.
The study subjects were asked to rate the aggression of each scene by pressing one of two response buttons at the end of each clip to indicated they thought the clip was more or less aggressive than the previous video.
As the boys watched the videos, a magnetic resonance imaging scanner collected data on their brain function and electrodes attached to the fingers tested for skin responses.
"The important new finding is that exposure to the most violent videos inhibits emotional reactions to similar aggressive videos over time and implies that normal adolescents will feel fewer emotions over time as they are exposed to similar videos," Grafman says in a statement.
The findings are published online in the Oxford Journal Social Cognitive and Affective Neuroscience.
