Disgust May Drive Some Types of OCD
Different Emotions May Play Role in Obsessive-Compulsive Disorder
May 9, 2003 -- Disgust rather than fear may drive some people with obsessive-compulsive disorder (OCD) to wash their hands incessantly or perform other irrational behaviors. A new study shows the brains of people with contamination preoccupation OCD react more strongly to disgusting images like rotting food than other people.
Researchers say the findings could signal a shift in thought about the causes of OCD. Certain groups of people with obsessive-compulsive disorder may have unwanted thoughts about cleanliness or contamination concerns because of an overreaction to disgust, not due to fear or anxiety about a potential disastrous outcome.
"Disgust can be misidentified as fear," says researcher Wayne K. Goodman, MD, chairman of psychiatry at the University of Florida's college of medicine, in a news release.
In the study, researchers compared the reactions of eight people with contamination preoccupation OCD with a group of healthy adults to a set of 30 pictures that had been rated in terms of emotional impact. The participants watched a series of threatening, disgusting, or neutral images, such as snakes bearing their fangs, flies on pumpkin pie, or a sunset, as magnetic resonance imaging (MRI) scans were taken of their brains.
The results appear in the current online edition of Biological Psychiatry.
Researchers found pictures that induced fear or disgust prompted reactions in different parts of the brain in both groups of participants. But the level of stimulation in certain areas of the brain prompted by the disgusting images was greater for people with OCD. The areas of the brain most affected by these images included those that process unpleasant taste and smells.
Although it's still too soon to say whether the findings might lead to new treatments for obsessive-compulsive disorders, researchers say they shed new light on the emotion of disgust.
"The findings get us to think about the role of disgust in our everyday lives," says Goodman. "In fact, people should take note of how many times they say they find something or someone disgusting. It reminds us that disgust is a bona fide emotion. Although it has similarities to fear, it has distinct differences."