Magnetoencephalographic study of the neural responses in body perception

A fundamental trait of human beings is the ability to discern information communicated by others. The human body is one of the important sources of such information. To date, several researchers have reported two body-selective regions in the brain-the extrastriate body area (EBA) and fusiform body area. As compared to the number of studies on spatial distribution, studies on the temporal processing of body perception are few. The electroencephalography (EEG) findings of a recent study indicate that observation of the human body induces a remarkable response leading to the generation of event-related-potentials that peak at 190 ms. However, source localization by using EEG has limitations. The advantage of magnetoencephalography (MEG) is that it enables localization of cortical activities and has excellent temporal resolution. In this study, we used MEG to measure the neural responses underlying the perception of the human body. Our results suggest that cortical activation induced by body images was observed in the bilateral EBA region with a latency of 190 ms and right-hemispheric dominance. Our study revealed the regions involved and the latency differences between these regions in body perception. Further, our results show the usefulness of MEG for body perception studies and suggest that like the face, the body plays a unique role in the human recognition process.