Neural mechanisms of perceptive and affective processing of body stimuli in Anorexia nervosa - are there developmental effects?

Objective Different components of body image processing seem to be reflected by different neural mechanisms. A core symptom of Anorexia nervosa (AN) is a disturbance of body image with correlates found on a neural level. The present study focusses at the neural processing of visual body stimuli of different weight categories in adolescent and adult AN patients. Method 33 adolescents aged 12–18 years (15 AN patients, 18 control participants) and 36 adult women (19 AN patients, 17 control participants) underwent functional magnetic resonance imaging (fMRI) while performing a perceptive and an affective body image task involving photographic stimuli of women belonging to different BMI categories. Results Differential effects on activation depending on the BMI of the women shown in the pictures were found in frontal brain regions, the thalamus, caudate and the fusiform gyrus. Group effects differentiating between AN patients and control participants were seen mainly in the caudate and insula. Discussion During a perceptive task, diminished activation of regions involved in perceptive and evaluative functions as well as emotional reasoning was seen in AN. During evaluation of the neural processing in an affective task there was a tendency towards activation differences reflecting reduced ability of size estimation and impaired integration of visual and body perception with emotions.