Guilderland, New York (PressExposure) November 02, 2009 -- The first study involved 161 nine to 12-year-olds and college students who played a non-violent game, a violent but cartoonish game or, age permitting, a violent teen game. Afterwards they played a video game which allowed them to punish a real-life opponent with blasts of noise. Immediate increases in aggression were witnessed among those who had played a violent game--whether it was a children's game or a bloodier teen game.
In second study researchers surveyed 189 high schoolers on their exposure to violent video games and programming, attitudes toward violence, personality traits and aggressive behaviors. They found that exposure to violent video games was a stronger predictor of violent behavior than the students' beliefs about violence, aggressive attitudes or gender.
The last study assessed 430 third- through fifth-graders over the course of five months. In that short time, researchers found that those children who played violent video games at the beginning of the study developed a more aggressive worldview and exhibited more violent behaviors than their peers. The difference was large enough that both teachers and peers noted the behaviors, in turn leading to social rejection.
Fortunately, the last chapter of Violent Video Game Effects on Children and Adolescents,also offers advice to parents on choosing video games, as does author Dr. Craig A. Anderson's homepage.