Using a functional MRI (fMRI) to measure underactivation in certain parts of the brain may soon be used over current diagnostic techniques, which usually don't identify obsessive-compulsive disorder (OCD) until it has already developed.

According to an article that recently appeared in the peer-reviewed journal Science, an estimated two to three percent of the population suffers from OCD, characterized by recurrent thoughts and sometimes socially crippling repetitive actions.

Researchers at the Cambridge University in the U.K. measured brain activity in a region of the brain involved in decision-making and behavior using fMRI, finding that participants who had OCD or were relatives of people with OCD showed underactivation in this area of the brain -- further suggesting the belief that OCD may be a genetic disorder.

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