Bushman, B., & Anderson, C. (2009, March). Comfortably numb: Desensitizing effects of violent media on helping others. Psychological Science, 20(3), 273-277. Retrieved June 9, 2009, doi:10.1111/j.1467-9280.2009.02287.x

Two studies tested the hypothesis that exposure to violent media reduces aid offered to people in pain. In Study 1, participants played a violent or nonviolent video game for 20 min. After game play, while completing a lengthy questionnaire, they heard a loud fight, in which one person was injured, outside the lab. Participants who played violent games took longer to help the injured victim, rated the fight as less serious, and were less likely to “hear” the fight in comparison to participants who played nonviolent games. In Study 2, violent– and nonviolent-movie attendees witnessed a young woman with an injured ankle struggle to pick up her crutches outside the theater either before or after the movie. Participants who had just watched a violent movie took longer to help than participants in the other three conditions. The findings from both studies suggest that violent media make people numb to the pain and suffering of others. (PsycINFO Database Record (c) 2009 APA, all rights reserved)(from the journal abstract)