gms | German Medical Science

Background: Anorexia Nervosa (AN) is a common psychiatric disease particularly in adolescent girls. Evidence from electrophysiology and neuroimaging measures in adult AN patients suggests that the processing of disorder relevant stimuli, like food pictures, is affected when compared to healthy control (HC) individuals. Adult AN patients show enhanced early event-related potential (ERP) amplitudes in response to both high- and low-caloric food pictures relative to neutral pictures, whereas healthy participants show enhanced ERPs only for high-caloric food pictures (Blechert et a., 2011). Such enhanced early visual attention to food-cues remains to be shown in adolescent patients.

Methods: The present pilot study uses high-density whole-head magnetoencephalography (MEG) to measure brain responses to a rapid stream of high- and low-caloric food pictures and neutral pictures of non-food items. MEG-based source localization enables the examination of the underlying neural activity generators. It is planned to include 20 female adolescent AN patients and 20 HC subjects. First analyses are presented showing data from AN patients measured thus far and age- and gender-matched HCs.

Results: Most noticeable, AN patients compared to HCs showed reduced neural source activity in general. Moreover, amplitude differences were observed at various intervals in frontal and occipital regions. Early occipital activity was enhanced for food pictures compared to non-food items, being more evident in AN Patients than in HCs. Later occipital activity showed no difference between food and non-food items in AN patients, whereas greater activation towards food pictures compared to non-food items was still present in the HCs.

Conclusions: These data suggest that adolescent AN patients may show enhanced early visual attention to food-cues, while later, more cognitively-governed neural processing is reduced. Further analyses will prove the significance of this initial impression.