"Demolishing the Competition: The Longitudinal Link Between Competitive Video Games, Competitive Gambling, and Aggression," a new study that will appear in the Journal of Youth and Adolescence, found that aggressive behavior is tied to competition, not violence, in videogames and gambling, according to Forbes.

The study followed self-reports from 1,771 high school students over four years, which put the study in the real world rather than a laboratory setting, a weakness of most studies that attempt to link videogames to aggressive behavior.  It found that there was moderate positive correlation between competitive video game play and aggression, and between competitive gambling and aggression. 

The study also found that there was a "small and mostly negative" correlation between non-competivie video game play and aggression.  Correlations between non-competitive gambling and aggression were small and positive. 

For the purposes of the study, aggression was defined as hostile verbal and physical behavior. 

The attempt to link violent entertainment to aggressive behavior has been going on for decades, at least since Dr. Fredric Wertham’s fraudulent study on comics in the 1950s that nearly destroyed the American comic business.   

More recently, one knee-jerk reaction to the Newtown school shootings was to blame violent videogames, despite the lack of any evidence linking them to the crime (see "Videogame, DVD 'Burning'"). 

Legislation on violent videogames has also been proposed (as an alternative to gun safety legislation) in the reaction to the Newtown shootings. 

But with this study, there is additional evidence that depictions of violence are not a cause of violence.