Brains of Bulimia Patients Wired Differently

ByABC News
January 6, 2009, 11:03 PM

Jan. 7 -- TUESDAY, Jan. 6 (HealthDay News) -- Brain circuitry involved in regulating impulsive behavior seems to be less active in women suffering from the eating disorder known as bulimia nervosa.

The frontostriatal regulatory circuits implicated in this study are mediated by both the neurotransmitter dopamine and the neurotransmitter serotonin.

So far, serotonin has been widely implicated in bulimia, which is often treated with antidepressants known as selective serotonin reuptake inhibitors (SSRIs). However, dopamine has not been studied closely in relation to bulimia nervosa.

"These findings argue for looking more directly into dopamine systems in eating disorders," said study author Rachel Marsh, an assistant professor of clinical psychology in the division of child and adolescent psychiatry at Columbia University in New York City.

"It's definitely preliminary . . . but it's not something to ignore," added Mary Tantillo, director of the Western New York Comprehensive Care Center for Eating Disorders. "We need to study this on adolescents who are closer to the onset of illness [Marsh has already started such a study]."

"This is pretty new stuff... We have a fair degree of understanding of the neurochemistry of eating disorders [but this study looked at] what actually happens in the brain when you engage in certain decision-making tasks or activities," said Daniel le Grange, director of the Eating Disorders Program at The University of Chicago and author of Help Your Teenager Beat an Eating Disorder and Treating Bulimia in Adolescence. "The main interest [of the study] at this time would be to understand how these disorders develop. Does the abnormality occur because someone has bulimia nervosa, or does it contribute to developing it?"

At this point, it's not clear if the brain differences are a cause or an effect of the disorder.

"These were adult women who had had the illness for a median of nine years," Marsh said. "We don't know if [the changes are] the product of having the disorder for nine years, or if something determines development of the disorder."