In the first of the current studies, researchers had 320 college students play either violent or nonviolent video games. After about 20 minutes of playing, a fight was staged outside the lab in which one of the actors appeared to be left moaning from the pain of a sprained ankle. The participants who played violent video games took 73 seconds compared to respond to the "victim," compared to the 16 seconds that the non-violent players took. Not only this, but the violent gamers also took notice the commotion less often than did the non-violent players; when they did, they were less likely than the non-violent gamers to rate it as serious.'[T]hese studies clearly show that violent media exposure can reduce helping behavior.'
In the second study, the researchers timed how long it took movie-goers — after watching either a violent or non-violent movie — to respond to an actress who dropped her crutches and had a hard time recovering them. The violent movie watchers took about 26% longer than the non-violent watchers.
Head researcher Brad Bushman says that "[p]eople exposed to media violence are less helpful to others in need because they are 'comfortably numb' to the pain and suffering of others, to borrow the title of a Pink Floyd song." He continues on to say that "[t]hese studies clearly show that violent media exposure can reduce helping behavior."
The researchers point out that the results of the two studies were very much the same, despite being executed in two different social settings — the lab vs. the real world. This, they say, underlines the fact that desensitization due to violent media is generalizable; in other words, one would expect to see the same results across a large variety of settings and circumstances.
The studies were conducted by researchers at the University of Michigan and Iowa State University.