Too much onscreen violence turning teens aggressive

A new study suggests that heavy exposure to screen violence in adolescence is changing the development of young people's brains, which is leading to increased aggression and reckless behaviour and decreased empathy.

Evidence presented at the Australian Council on Children and the Media conference in Sydney showed brain imaging studies which recorded the way violent material changes brain activation in the short term and brain function in the long term.

According to research presented by Dr Wayne Warburton, deputy director of the Children and Families Research Centre at Macquarie University, experiencing screen violence reduces the development of the frontal lobe, which is responsible for impulse control and inhibits aggression, the Sydney Morning Herald reported.

Exposure to violent material also activates the brain's limbic system, which is responsible for emotional response and memory.

Dr Warburton said that images of violence could be stored in the brain in the same way that post-traumatic stress disorder patients store memories of trauma.

Violent films and games such as Grand Theft Auto and World of Warcraft also activate the brain's right hemisphere, which controls negative feelings such as anger, jealousy and sadness.

The impact on the brain is cumulative, with the heavier the exposure, the more severe the changes.

Dr Michael Nagel, associate professor of education at the University of the Sunshine Coast, said the two most vulnerable periods in brain development were in early childhood and puberty.

The peak age for video game usage is from 11-14 years.