Researchers at Indiana University School of Medicine asked 44 adolescents to play either a violent or a nonviolent video game for 30 minutes. They used functional magnetic resonance imaging (fMRI) to measure brain activity while participants performed a series of tasks measuring inhibition and concentration immediately after playing video games. The researchers announced Tuesday that they had documented differences between the two groups.
The groups didn't differ in accuracy or reaction time, but those who played the violent game showed more activity (brightly colored scans) in the amygdala. That is an area of the brain connected with emotional arousal. They showed less activity in an area associated with executive functions such as planning, shifting, and controlling and directing thoughts and behavior, according to researchers.
Those who played the nonviolent games showed activation in the portions of the brain associated with inhibition, concentration, and self-control and less activity in areas connected with emotional arousal, the study revealed. The study aims to address a long-lasting debate over the influence violence in media can have on youth.
Experts, including American Psychological Association Fellow Craig Anderson, have addressed several of the arguments that criticize studies linking media violence and aggression. Anderson said that the current findings are consistent and correlations between the two groups are significant. He has pointed out in APA publications that entire scientific fields, such as astronomy, are based on correlation.
Earlier studies have indicated a correlation between exposure to media violence and brain functioning, but the researchers didn't actively manipulate participants' exposure to violence, said William Kronenberger, Ph.D., associate professor of psychology in the Department of Psychiatry at IU's medical school. In this study, researchers randomly assigned adolescents to play either a violent or a nonviolent game, he said.
"Therefore, we can attribute the difference between the groups specifically to the type of game played," Kronenberger said.
Dr. Vincent Mathews, an Indiana University radiology professor who led the study, said it reveals effects on short-term brain function.
"During tasks requiring concentration and processing of emotional stimuli, the adolescents who had played the violent video game showed distinct differences in brain activation than the adolescents who played an equally exciting and fun--but nonviolent--game," he said. "Because of random assignment, the most likely factor accounting for those differences would be the group to which the volunteers were assigned."
The researchers plan further study to understand more about the connection between exposure to media violence and brain function.