Actually, the study rocklobster mentioned had nothing to do with violent media on children. Rather, it was a study on social learning.
http://en.wikipedia.org/wiki/Bobo_doll_experimentThe results concerning gender differences strongly supported Bandura's prediction that children are more influenced by same-sex models. Boys exhibited more aggression when exposed to aggressive male models than boys exposed to aggressive female models. When exposed to aggressive male models, the number of aggressive instances exhibited by boys averaged 104 compared to 48.4 aggressive instances exhibited by boys exposed to aggressive female models.
While the results for the girls show similar findings, the results were less drastic. When exposed to aggressive female models, the number of aggressive instances exhibited by girls averaged 57.7 compared to 36.3 aggressive instances exhibited by girls exposed to aggressive male models.
Bandura also found that the children exposed to the aggressive model were more likely to act in verbally aggressive ways than those who were not exposed to the aggressive model. The number of imitative verbal aggressions exhibited by the boys was 17 times and 15.7 times by the girls. In addition, the results indicated that the boys and girls who observed the nonaggressive model exhibited far less non-imitative mallet aggression than in the control group, which had no model.
The experimenters came to the conclusion that children observing adult behavior are influenced to think that this type of behavior is acceptable thus weakening the child’s aggressive inhibitions. The result of reduced aggressive inhibitions in children means that they are more likely to respond to future situations in a more aggressive manner.
Lastly, the evidence strongly supports that males have a tendency to be more aggressive than females. When all instances of aggression are tallied, males exhibited 270 aggressive instances compared to 128 aggressive instances exhibited by females.
On top of this study having absolutely
nothing to do with media such as television and video games, there are numerous critiques, such as the selection of subjects not being broad enough or diverse enough, as well as manipulation of the subjects, i.e., the subjects were taunted and told "No you can't play with THESE toys," which of course would make the kids upset, meaning their aggression might have nothing to do with the behavior displayed by adults, but rather that they were annoyed and upset that they couldn't have what they wanted. Which is pretty typical of ALL kids when you tell them they can't have something they want.
It's actually very nuanced and complex, for example, Bandura (the scientist who conducted the study) said that motivation is a key factor in behavior. If someone does not have the desire to emulate an action or behavior in the first place, they won't. Being able to pay attention to the behavior is key too, if someone is distracted or not fully paying attention, they're less likely to emulate the behavior.
So the study is a lot, LOT more complicated than "Kids who saw people beating up a clown doll did it too!" and also is completely unrelated to video games/movies, which there have been studies to show that violent games and movies actually
decrease the urge to be violent...which is what the link in Star's opening post also said as well.