While the media does like to portray various effects of playing games on the brain, the reality is that there are actually were little, if any, effects how playing games could have dramatic long-lasting changes on our brains.
One of the more commonly observed things has been that people who do play a lot of shooting games and strategy games can have improved visual reaction times or are a little better at micromanaging. However, there is no drastic effects. Furthermore, games do not cause aggresive behavior, there is no substantial evidence for that claim :)