Two researchers at Iowa State University are part of an international team that’s issued a new report on the effects of exposure to violent images — such as scenes in movies, games or pictures in comic books. I.S.U. psychology professor Craig Anderson is president of the International Society for Research on Aggression (IRSA).

He appointed a commission which released the report that concludes research clearly shows media violence can trigger aggressive thoughts and feelings. “My hope is that (the report) will inspire some parent groups and education groups to redouble their efforts to help educate parents about the importance of looking at the amount of media violence that’s in their children’s diets,” Anderson said.

The Media Violence Commission includes I.S.U. associate professor of psychology Douglas Gentile. The commission’s report is published in the September/October issue of the journal Aggressive Behavior. Anderson said he’s often surprised to find many parents don’t seem to realize exposure to media violence does increase an individual’s relative risk to become aggressive. Other parents recognize the risk, but don’t take steps to limit their kids’ exposure.

“A lot of parents just kind of throw up their hands and sort of say ‘it’s too difficult,’ when in fact it’s not that awfully difficult, although it certainly takes some effort,” Anderson said. For example, Anderson advises parents to set limits on what movies their kids can watch.

“I enjoy the occasional violent movie myself and I’m frequently appalled at parents who bring their children to movies that are clearly not appropriate for them,” Anderson said. In their report, the commission stated violent images can act as “triggers” for activating aggressive thoughts and feelings already stored in memory.

If the aggressive thoughts and feelings are activated over and over again, because of repeated exposure to media violence, they become chronically accessible, and thus more likely to influence behavior.

The commission suggests more effort is needed to improve movie and video game ratings, classifications and public education about the effects of media on children. Anderson said that effort should be led by an independent entity – rather than an industry-influenced group.