Sex, food and drugs give you a high - and so does aggression, according to a new study.
The study, by researchers at Vanderbilt University, shows for the first time that the brain processes aggression as a reward - much like sex, food and drugs - offering insights into the human propensity to fight.
It also explains the fascination people have with violent sports like boxing and bullfighting, Sciencedaily reported.
Findings of the study have been published in the latest issue of the journal Psychopharmacology.<b1>
"Aggression occurs among virtually all vertebrates and is necessary to get and keep important resources such as mates, territory and food," said Craig Kennedy of Vanderbilt University.
"We have found that the 'reward pathway' in the brain becomes engaged in response to an aggressive event and that dopamine is involved."
Dopamine is produced in response to rewarding stimuli such as food, sex and drugs of abuse. The new study has found that it also serves as positive reinforcement for aggression.
The Vanderbilt experiments - done on mice-are the first to demonstrate a link between behavior and the activity of dopamine receptors in response to an aggressive event.
"We learned from these experiments that an individual will intentionally seek out an aggressive encounter solely because they experience a rewarding sensation from it," Kennedy said.
"This shows for the first time that aggression, on its own, is motivating, and that the well-known positive reinforcer dopamine plays a critical role."