Researchers say games such as Grand Theft Auto can promote anti-social behaviour. (file pic)

Violent video games glorifying antisocial characters could increase teenage gamers’ risk of criminal and other risky behaviour like smoking and alcohol use, a US study has found.

Adult-rated games also affect teenage users’ self-image, according to the study by Dartmouth College researchers published on Monday in the Journal of Personality and Social Psychology.

A previous Dartmouth study published in 2012 had already found such video games could incite teens to drive carelessly.

Other studies have linked violent video games to adolescent aggressiveness and violence.

But this latest study ‘is important because it is the first to suggest that possible effects of violent video games go well beyond violence to apply to substance use, risky driving and risk-taking sexual behaviour,’ Dartmouth professor of pediatrics and co-author James Sargent said in a statement.

In fact, youths who play these types of video games may identify themselves to the antisocial protagonists they feature.

‘With respect to playing deviant video game characters, we feel it best to follow the admonition of Kurt Vonnegut in ‘Mother Night:’ ‘We are what we pretend to be, so we must be careful about what we pretend to be,’ said lead author Jay Hull, who chairs Dartmouth’s Department of Psychological and Brain Sciences.

For the study, researchers questioned 5000 randomly chosen US teenagers over a four-year period by phone.

Among the factors they examined were playing three games glorifying violence – Grand Theft Auto, Manhunt and Spiderman – and other mature-rated games.

The study then found links between games of this nature and changes in a broad range of high-risk behaviours.

‘This is due, in part, to changes in the users’ personality, attitudes and values, specifically making them more rebellious and thrill-seeking,’ the study said.

Researchers found the effects to be similar for both men and women, and strongest among those who played the most or played games with antisocial protagonists.