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

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.

Distorted images of one's own body activates the prefrontal cortex and limbic/paralimbic system in young women: a functional magnetic resonance imaging study.

BACKGROUND: Our aim was to study the gender differences in brain activation upon viewing visual stimuli of distorted images of one's own body. METHODS: We performed functional magnetic resonance imaging on 11 healthy young men and 11 healthy young women using the "body image tasks" which consisted of fat, real, and thin shapes of the subject's own body. RESULTS: Comparison of the brain activation upon performing the fat-image task versus real-image task showed significant activation of the bilateral prefrontal cortex and left parahippocampal area including the amygdala in the women, and significant activation of the right occipital lobe including the primary and secondary visual cortices in the men. Comparison of brain activation upon performing the thin-image task versus real-image task showed significant activation of the left prefrontal cortex, left limbic area including the cingulate gyrus and paralimbic area including the insula in women, and significant activation of the occipital lobe including the left primary and secondary visual cortices in men. CONCLUSIONS: These results suggest that women tend to perceive distorted images of their own bodies by complex cognitive processing of emotion, whereas men tend to perceive distorted images of their own bodies by object visual processing and spatial visual processing.