According to new research out of the University of Missouri, in partnership with Ohio State University and VU University of Amsterdam, violent video games may both increase aggression among players and desensitize them to violent imagery.
During the study 70 participants were randomly assigned to play a "violent" video game, such as Call of Duty, Grand Theft Auto, or Killzone, while others were assigned to play a "non-violent" video game (the names of which are not mentioned in the official press release). Participants who played 25 minutes of a violent video game showed less neural response to violent imagery, such as a man having a gun shoved in his mouth, and were more likely to behave aggressively when told they were in competition with another participant. Players' degree of reaction to violent images also predicted their level of aggression toward other players, with the participants showing the least neural response to violent images displaying more aggressive behaviour. Moreover, participants who played video games habitually before the study showed less response to the violent images than others, regardless of whether they were selected to play a violent or non-violent video game in the present study.
Of course, a degree of skepticism is healthy whenever one is presented with research, and certain questions are left unanswered in the press release.
What are the "non-violent" video games? This is important because:
Is violence really what's causing aggression? Other recent research has demonstrated that sports and racing games may encourage even more aggression than "violent" video games. Is violence causing the effect, or are other elements like competitiveness and reward-seeking the culprits? Knowing what games are included in the control group is important in evaluating this research.
Are all violent video games the same? Multiple games were included in the violent category. Is the result observed attributable to all four of the games, or just one or two? This is unlikely to be answered in the research because if all games were played by equal numbers of participants there would not be enough people playing each game to yield reliable results between groups.
Cause and effect. This research indicates that, as a group, people who habitually play video games showed less response to violent imagery. Is that because of video games, or because certain types of people are drawn to those games, and they are skewing the results for the greater group?
The research is scheduled to be published in the upcoming Journal of Experimental Psychology. As always, if I can get my hands on it I'll be back for a more in-depth analysis.