Events which most cause this are visual, highly dramatic, and generally conceptually simple. What is most important is not level of violent content seen, rather whether an aggressive interpretation by the viewer of the scene was made.
Desensitization is a decreased anxiety and aversion to violence.
Violence or aggression is often seen as more acceptable than before. The two can produce violent thoughts when viewers are not repelled by or made anxious of the event. Such is their relationship to priming. Often, frequent viewers of violence report they feel like they could become a victim more often than do infrequent viewers. They influence how we believe situations develop as well as their likely outcomes.