Bodily self-relatedness in vicarious touch is reflected at early cortical processing stages.

Abstract

Studies have suggested that there is a strong link between the bodily self and the mechanisms underlying vicarious representations. Here, we used somatosensory ERPs to investigate the temporal dynamics of vicarious touch for stimuli that are more or less related to one's own body (human hands vs. rubber gloves). We found that vicarious touch effects were restricted to self-relatable events (human hands) at early implicit stages of somatosensory processing (P45). At later more cognitive stages of processing (late positive complex, LPC), the vicarious touch effect was stronger for self-relatable events (touch on human hands) than nonself-relatable events (touch on rubber gloves) but present for both. Both effects, but especially the vicarious touch effect for human hands at P45, were stronger in individuals with higher levels of interoceptive awareness. Our results confirm that there is a tight link between vicarious touch and the bodily self and characterize P45 effects of vicarious touch as its likely neural basis. We propose that vicarious processes and the embodied self may be representationally indistinct (linked in a common neural representation) at early implicit somatosensory processing stages.