An imaging study using fMRI has shown distinct differences in responses in the region of the brain known as the insula in women with anorexia nervosa and may shed light on the cause of the disorder. The insula is important for recognizing taste and the researchers think that women with anorexia may have difficulty recognizing taste and responding to the pleasure of food.
The study the study led by Angela Wagner, M.D., University of Pittsburgh School of Medicine, and Walter H. Kaye, M.D., of the University of Pittsburgh and the University of California, San Diego (UCSD) Schools of Medicine involved 16 women who had recovered from anorexia nervosa and a control group of 16 women who did not suffer from the disorder. They measured their brains’ reactions to pleasant taste (sucrose) and neutral taste (distilled water.) The findings suggest that women who have recovered from anorexia had significantly reduced response in the insula and related brain regions when compared to the control group. These areas of the brain recognize taste and judge how rewarding that taste is to the person.
“We know that the insula and the connected regions are thought to play an important role in interoceptive information, which determines how the individual senses the physiological condition of the entire body,” said Kaye.
“Interoception has long been thought to be critical for self-awareness because it provides the link between thinking and mood, and the current body state.”
Anorexia nervosa is a disorder characterized by the pursuit of thinness, leading to emaciation and may be lethal in ten percent of cases. Women are nine times more likely to suffer from anorexia than men.