February 20, 2009

Thrill seeking may be based in the brain

The brains of thrill seekers differ from those of who avoid risky behavior, U.S. researchers suggest.

Psychologists Jane E. Joseph, Xun Liu, Yang Jiang and Thomas H. Kelly of the University of Kentucky, along with Donald Lyman of Purdue University, recruited two sets of volunteers -- high sensation seekers or low sensation seekers -- based on their responses to personality surveys and risk-taking questionnaires.

Both groups were shown a variety of photographs -- ranging from mundane scenes of cows and food to very emotional and arousing images such as erotic scenes and violent pictures -- while having their brains scanned with functional magnetic resonance imaging.

The study, published in the journal Psychological Science, found there was increased activity in the brain region known as the insula when high sensation seekers viewed the arousing photographs. Previous research has shown that the insula is active during addictive behaviors, such as craving cigarettes, the researchers say.

However, when low sensation seekers looked at arousing photographs, there was increased activity in the frontal cortex area of the brain -- important for controlling emotions.

The study authors note that their findings may indicate the way by which sensation seeking results in negative behaviors, including substance abuse and anti-social behavior.