Violent images in movies, TV or computer games CAN act as triggers for aggression, says new report

Grand Theft Auto IV was a critically-acclaimed 18-rated game, but there were concerns about younger players emulating the violence they saw on-screen

Violent TV, films and video games do increase aggression, an international panel of experts has said, as they warn parents to keep an eye on what their children are watching. 

The report for the The International Society for Research on Aggression (IRSA) concluded that that evidence shows that the consumption of media violence can act as a trigger for aggressive thoughts or feelings already stored. 

They claim exposure to violent images in different media, such as movies and video games, increases the relative risk of aggression - defined as intentional harm to another person verbally or physically. 

The panel also warn parents that a ratings system is no substitute for the watchful eye of a parent.