NASHVILLE, Jan. 2 (UPI) -- Risk-takers face an uphill battle in keeping their New Year's resolutions due to the way their brains process dopamine, U.S. researchers found.
Lead author David Zald of Vanderbilt University in Nashville said the neurotransmitter dopamine is produced by a select group of cells in the brain. These dopamine-producing cells have receptors called autoreceptors that help limit dopamine release when the cells are stimulated.
"We've found that the density of these dopamine autoreceptors is inversely related to an individual's interest in and desire for novel experiences," Zald said in the statement. "The fewer available dopamine autoreceptors an individual has, the less they are able to regulate how much dopamine is released when these cells are engaged."
The study, published in the Journal of Neuroscience, found the novelty and other potentially rewarding experiences that normally induce dopamine release will produce greater dopamine release in these individuals.
Dopamine has been long known to play an important role in how people experience rewards such as food, sex, cocaine and amphetamine, Zald said.
"Novelty-seeking personality traits are a major risk factor for the development of drug abuse and other unsafe behaviors," Zald said in a statement.