Brain activation during the perception of distorted body images in eating disorders

Abstract 

Eating disorder (ED) patients have severe disturbances in the perception of body shape and weight. The authors investigated brain activation patterns during the perception of distorted body images in various subtypes of ED. Participants comprised 33 patients with EDs (11 with restricting-type anorexia nervosa (AN-R), 11 with binging–purging type anorexia nervosa (AN-BP), 11 with bulimia nervosa (BN)) and 11 healthy women. Functional magnetic resonance imaging was used to examine cerebral response to morphed images of subjects' own bodies, as well as that of another woman. The amygdala was significantly activated in AN-R patients, AN-BP patients, and healthy women in response to their own fat-image, but this did not occur in BN patients. The prefrontal cortex (PFC) was significantly activated in AN-BP patients and healthy women, but not in AN-R and BN patients. Our results showed that the various EDs are different with respect to significant activation of the amygdala and PFC during the processing of participants' own fat-image. Brain activation pattern differences between the various EDs may underlie cognitive differences with respect to distorted body image, and therefore might reflect a general failure to represent and evaluate one's own body in a realistic fashion.

Keywords: Anorexia nervosa, Bulimia nervosa, Body image, Functional MRI, Amygdala, Prefrontal cortex