Children who regularly play violent video games could be thinking up though patterns that affect their behavior in real life.

"If you practice over and over, you have that knowledge in your head. The fact that you haven't played the piano in years doesn't mean you can't still sit down and play something. It's the same with violent games - you practice being vigilant for enemies, practice thinking that it's acceptable to respond aggressively to provocation, and practice becoming desensitized to the consequences of violence,"  Douglas Gentile, an associate professor of psychology and lead author of the study said in an Iowa State University news release.

The team found that as the children continued playing video games on a regular basis their thoughts got progressively more aggressive and were more likely to react violently.

"Violent video games model physical aggression," Craig Anderson, Distinguished Professor of psychology and director of the Center for the Study of Violence at Iowa State and co-author of the report, said in the news release. "They also reward players for being alert to hostile intentions and for using aggressive behavior to solve conflicts. Practicing such aggressive thinking in these games improves the ability of the players to think aggressively. In turn, this habitual aggressive thinking increases their aggressiveness in real life."

The researchers followed 3,000 children in third, fourth, seventh, and eighth grades for three years. The team looked at how often the participants playing video games and if their behavior changed. They found that boys tended to display more aggressive behavior and play more video games than girls. When the researchers controlled gender playing video games was correlated with more violent behavior in both girls and boys. The team also controlled for starting aggression levels.

"The results make a pretty strong argument that gender and age really don't affect this relationship between video game play, aggressive thinking and aggressive behavior," Sara Prot, a graduate student in psychology at Iowa State said in the news release. "There are lasting effects on thinking and behavior. You can't say one group, because of their gender, age or culture, is protected from the effects in some special way."