APA links violent games to aggression, asks devs to improve parental controls
The American Psychological Association's Task Force on Violent Media has publicly affirmed that playing violent video games is a consistent "risk factor" for both increased aggressive thoughts and behaviors (though not necessarily violence) and decreased empathy, based on its review of research on the topic published between 2005 and 2013.
More importantly for game makers, the APA's public statement includes a call for the game industry to "design video games that include increased parental control over the amount of violence the games contain" and encouragement for "developers to design games that are appropriate to users’ age and psychological development."
The APA's statement also comes with significant caveats: the organization is upfront about the fact that the task force didn't examine much research about how violent video game play influences subjects over long periods of time, nor did it feel confident about its data on how violent video games affect children under 10.
“While there is some variation among the individual studies, a strong and consistent general pattern has emerged from many years of research that provides confidence in our general conclusions,” task force leader Mark Appelbaum said in the aforementioned statement. “As with most areas of science, the picture presented by this research is more complex than is usually included in news coverage and other information prepared for the general public.”
Appelbaum is referring, in part, to the task force's conclusion that playing violent video games is just one of many "risk factors" for aggression leading to violent or destructive behavior. He goes on to recommend that further research be conducted into the effects violent video games can have on people already "at risk" of committing violence due to other risk factors (substance abuse, a history of trauma, and the like.)
For more information about how the task force conducted its research, you should read the report [PDF] in full. Kotaku has also published a good counterpoint to the report highlighting some potential flaws in its methodology.
Based on this research, the APA has issued a new "Resolution on Violent Video Games" to replace the one it issued in 2005. It doesn't include any explicit messages for game makers, but does call for improved education of parents and other authority figures about violence in games and encourages the ESRB to refine its content ratings system.