Individuals who have fewer dopamine "auto-receptors" -- which control the release of the brain chemical -- may be more prone to risk-taking, researchers say.

HealthDay News reported Dec. 30 that individuals with a deficiency of dopamine auto-receptors experience higher levels of dopamine release during thrill-seeking activities, which reinforces and rewards risk-taking.

"It starts to suggest that these auto-receptors might be an appropriate target for drug abuse," said lead author David H. Zald of Vanderbilt University. "[I]f you can understand the basic risk factors, you may ultimately be able to both reduce the risk for drug abuse or, more probably, readily treat people during the withdrawal stage of drug abuse."

Zald said the intent would not be to reduce risk-taking, which he said would lead to a "very boring society."

"But it is a [personality] style that does put people at greater risk for developing troubling drug-abuse problems," he said. "And now, we've been able to link this specific personality type with a specific aspect of the dopamine neurotransmitter system."

The study was published in the Dec. 31, 2008 issue of the Journal of Neuroscience.