Scientists have shed light on the brain chemistry behind "gut feelings", it emerged today.
A study has found strong evidence that the brain chemical dopamine plays a key role when making instinctive choices.
People frequently experience a "gut feeling" that helps them make a decision.
The choice they make is dependent on how often it was associated with positive outcomes in the past, say researchers.
But patients with Parkinson's disease, whose brains lack dopamine, have difficulty making these kind of choices.
To understand why, scientists developed a computer model on the effects of Parkinson's disease and the medications used to treat it, which boost dopamine levels.
Dopamine is a neurotransmitter which relays information between nerve cells.
The researchers found that patients taking medication were overly influenced by positive outcomes, while those off their medication were more influenced by negative outcomes.
Psychologist Dr Michael Frank, from the University of Colorado at Boulder, who led the study, said: "Because Parkinson's disease is caused by lower levels of the brain chemical dopamine, and the medications increase concentrations of this chemical, these results provide strong evidence that dopamine levels play a critical role in developing our likes and dislikes."
The finding, reported in the journal Science, could help researchers understand more about the brain and lead to better treatment for disorders such as schizophrenia. - (PA)