Here is the link that announces new perception of aggression with the video games.
What the most recent research found is that the aggression is not born from violent video games but from the frustration that you screamed in rage or thrown down a controller after missing a jump in a video game or getting shot from across the level.
In one case, the subjects first had to hold their hand in ice-cold water for 25 seconds, then after playing a game were asked to determine how long the next person would have to put their hand in. In reality, everyone got 25 seconds, but the researchers found that subjects who had played difficult versions of games assigned the next player 10 seconds more on average than people who had played an easy game. From this experiment what we can find is that level of violence doesn't matter for the aggression which gives proofs that violent game doesn't bring one person to the aggressive mode.