FRIDAY, July 2 (HealthDay News) -- A new study of prisoners and game-playing suggests that there's a link between damage to a specific part of the brain and psychopathic behavior, although it's not clear how they're connected.

In the study, researchers looked for connections between 47 prisoners, some of whom were diagnosed as psychopaths, and patients they had previously studied who had damage to an area of the brain known as the ventromedial prefrontal cortex, a region crucial to emotions such as empathy and guilt.

The researchers found that the psychopaths made similar decisions -- and played in a similar style -- to the brain-damaged patients in a game designed to shed light on how they react to the world.

In the "Ultimatum Game," for example, two players got to divide up and keep a certain amount of money if they could agree on how to split it. But if the "responder" rejected the offer, neither player got any money. Unlike more rational inmates, who would accept any amount of money as an alternative to getting nothing, prisoners diagnosed with primary psychopathy reacted angrily to what they viewed as unfairly low offers. They were much more prone to reject such offers, leading both players to lose everything.

"They're quick to anger, and they don't regret their bad treatment of others," said Michael Koenigs, assistant professor of psychiatry in the University of Wisconsin School of Medicine and Public Health, in a university news release.

"There are interesting parallels between psychopaths and our ventromedial prefrontal cortex patients," he continued. Such research, he said, is "an important hint" that the brain damage may play a role in the development of psychopathic behavior.

The study appears in the June issue of the journal Neuropsychologia.

More information

The U.S. National Library of Medicine has more information on mental health.