The Sensitzation Theory

The sensitization theory is sort of a reverse modeling effect, whereby viewers react so strongly to seeing some violence and have such a traumatized perceived reality that they are actually less likely to imitate it as a result.  This is most likely to occur with very extreme violence and might be the reaction of someone who has never seen anything other than a G-rated movie to seeing a graphically violent R-rate film.

The behavioral tendency away from violence might arise from either the arousal of anxiety about the violence and/or the arousal of empathy for the victim of the violence.