Background:In spite of many similarities in the psychopathology of anorexia nervosa (AN) and bulimia nervosa (BN), the 2 groups seem to differ in terms of body image disturbances. Therefore, the aim of the present study was to compare neuronal correlates of viewing photographs of one's own body and another woman's body in patients with these forms of eating disorders as well as controls. Methods: We performed functional magnetic resonance imaging while women with AN (n = 13), BN (n = 15) and healthy controls (n = 27) viewed 16 standardized pictures of their own body and another woman's body, taken while the participants were wearing a bikini. Results: When viewing their own body, participants with AN and BN showed reduced activity in the inferior parietal lobule compared with healthy women. In response to looking at another woman's body, participants with AN had higher amygdala activity than did those in the BN and control groups. Limitations: The generalizability of the results is limited by the small sample size. Conclusion: Our data suggest decreased attentional processes in AN and BN toward one's own body, possibly reflecting body-related avoidance behaviour. Enhanced limbic activity elicited by looking at another woman's body in participants with AN might be a neural correlate of stronger emotional activation and enhanced vigilance, possibly resulting from social comparison processes. Our study reveals hints about body image-associated alterations in brain activity, which seem to be more pronounced among women with AN than among those with BN.

The present study aimed to further explore the mechanisms underlying the perception of human body shapes. Behavioral and electrophysiological inversion effects were studied for human bodies with and without heads and for animal bodies (cats, dogs, and birds). Recognition of human bodies (with heads) was adversely affected by stimulus inversion, and the N170 had longer latencies and higher amplitudes for inverted compared to upright human bodies. Human body shapes presented without heads yielded the opposite result pattern. The data for animal bodies did not yield consistent effects. Taken together, the present findings suggest that human bodies might be processed by specialized cortical mechanisms which are at least partly dissociable from mechanisms involved in object or face processing.

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The function of the human mediodorsal thalamic nucleus (MD) has so far eluded a clear definition in terms of specific cognitive processes and tasks. Although it was at first proposed to play a role in long-term memory, a set of recent studies in animals and humans has revealed a more complex, and broader, role in several cognitive functions. The MD seems to play a multifaceted role in higher cognitive functions together with the prefrontal cortex and other cortical and subcortical brain areas. Specifically, we propose that the MD is involved in the regulation of cortical networks especially when the maintenance and temporal extension of persistent activity patterns in the frontal lobe areas are required.

In the present study, we investigated how different processing stages involved in the perceptual analysis of biological motion (BM) are reflected by modulations in event-related potentials (ERP) in order to elucidate the time course and location of neural processing of BM. Data analysis was carried out using conventional averaging techniques as well as source localization with low resolution brain electromagnetic tomography (LORETA). ERPs were recorded in response to point-light displays of a walking person, an inverted walking person and displays of scrambled motion. Analysis yielded a pronounced negativity with a peak at 180 ms after stimulus onset which was more pronounced for upright walkers than for inverted walkers and scrambled motion. A later negative component between 230 and 360 ms after stimulus onset had a larger amplitude for upright and inverted walkers as compared to scrambled walkers. In the later component, negativity was more pronounced in the right hemisphere revealing asymmetries in BM perception. LORETA analysis yielded evidence for sources specific to BM within the right fusiform gyrus and the right superior temporal gyrus for the second component, whereas sources for BM in the early component were located in areas associated with attentional aspects of visual processing. The early component might reflect the pop-out effect of a moving dot pattern representing the highly familiar form of a human figure, whereas the later component might be associated with the specific analysis of motion patterns providing biologically relevant information.