Watchdog groups have long complained about the effect of violence in the media on kids. But new research shows it's not just gunfights that will fuck people up — mean girl behavior onscreen could be contagious too.

In a study published in the intimidating-sounding journal Aggressive Behavior (via ScienceDaily), researchers had 250 college women watch one of three scenes: a fatal gun- and knife-fight, a scary but nonviolent scene, and a scene that "portrayed relational aggression, where girls steal boyfriends, spread malicious gossip and kick someone out of their social circle." Then they gave the women a Stroop test (standard in many psych experiments), which measured how fast they reacted to either aggressive or neutral words. The women who had watched the fight and the mean-girl scene reacted much more quickly to aggressive words than did the ladies who had watched the clip that was simply scary. According to the study authors, this means the women had internalized the aggression they saw, possibly beginning to see it as normal. Study author Jennifer Ruh Linder says,

Past research has shown that viewing physical violence on TV activates aggressive scripts in the brain, but our findings suggest that watching both onscreen physical or relational aggression activates those cognitive scripts. Viewers don't simply choose to imitate TV characters or make a conscious decision to engage in aggressive behavior. Aggressive reactions are more automatic and less conscious than most people assume.

Adds coauthor Douglas Gentile, "What this study shows is that relational aggression actually can cause a change in the way you think. And that matters because of course, how you think can change your behavior." The study didn't look at the women's actions after they watched the clips, so it's not clear if they actually got meaner. But TV meanness did appear to get under their skin — and it's not such a stretch to assume that watching backstabbing bitches on the small screen might lead you to believe that such bitchery is normal. Further research will have to determine if watching Gossip Girl or Real Housewives will actually make you an asshole, but I wouldn't be surprised.

Nasty People in the Media Prime the Brain for Aggression [ScienceDaily]