Bulimia Linked to Impulsivity, Brain Circuit Abnormalities
Abnormalities may underlie patients' inability to regulate binge-type eating
TUESDAY, Jan. 6 (HealthDay News) -- Compared to women without eating disorders, women with bulimia nervosa respond more impulsively during psychological testing and show brain circuit abnormalities, according to study findings published in the January issue of the Archives of General Psychiatry.
Rachel Marsh, Ph.D., and colleagues at the New York State Psychiatric Institute and the College of Physicians and Surgeons at Columbia University in New York City, used functional MRI to compare 20 patients and 20 healthy controls during the performance of the Simon Spatial Incompatibility task.
Compared to controls, the investigators found that patients responded faster and made more errors on conflict trials that required self-regulatory control. Following incorrect conflict trials, the patients also responded faster on congruent trials. The researchers also found that patients had a lower activation of their frontostriatal circuits even when they did respond correctly to the trials.
"These group differences in performance and patterns of brain activity suggest that individuals with bulimia nervosa do not activate frontostriatal circuits appropriately, perhaps contributing to impulsive responses to conflict stimuli that normally require both frontostriatal activation and the exercise of self-regulatory control to generate a correct response," the authors write. "We speculate that this inability to engage frontostriatal systems also contributes to their inability to regulate binge-type eating and other impulsive behaviors."