Importance of the early visual cortex and the lateral occipito-temporal cortex for the self-hand specific perspective process.

Visual self-body recognition is one of the fundamental cognitive functions, and a major contributor to social development. Previous studies have shown that body identity judgement becomes difficult when subjects viewed their hand from a third-person perspective, and that this perspective effect was not observed when viewing the hand of another person, indicating that there are brain regions which are more strongly influenced by the perspective of one's own body than the body of another person. In this study, we aimed to depict the brain network contributing to the integration of perspective and identity of human bodies. We conducted a functional magnetic resonance imaging experiment where 29 participants observed their own or someone else's hand from first- and third-person perspectives. In the univariate analysis, none of the brain regions showed an interaction between perspective and body identity. However, in the searchlight and region-of-interest multivoxel pattern analysis (MVPA), decoding accuracies of self-hand from a first-person vs. those from a third-person perspective were higher than the decoding accuracies of other-hand from a first-person perspective vs. those from a third-person perspective in the early visual cortex. In addition, psychophysiological interaction analysis revealed a stronger effect of perspective of the self-hand than the other-hand condition in connectivity between the lateral occipito-temporal cortex and the early visual cortex, overlapped with the region depicted by MVPA. Our results suggest that the specific link between self-hand and first-person perspective is associated with identity-dependent perspective representations of the early visual cortex and functional connectivity between the early visual cortex and lateral occipito-temporal cortex, elucidating the nature of self-body recognition.