The contribution of body perception to self-identity: an event-related potential study.

Abstract

This study used electroencephalography (EEG) and personalized avatars to investigate the neural mechanisms underlying personal identity perception. Compound avatar images combining participants' own faces and bodies, as well as those of others, were generated from photographs. Participants underwent an embodiment training for each avatar type in a virtual reality environment, where they controlled the avatar's actions during physical exercise tasks. Subjective assessments by participants confirmed a stronger identification with avatars representing their own identity compared to those representing others. Analysis of event-related potentials (ERPs) evoked by viewing the avatar revealed that avatars representing the participants' self-identity elicited weaker N2 and P1 responses compared to avatars representing other identities. No significant effects on N170 responses were observed. Control conditions utilizing avatars with modified body characteristics confirmed that the reduction in N2 amplitude was specifically related to identity perception rather than variations in visual body size. These findings suggest that the perception of self-identity occurs rapidly, within ∼200 ms, indicating the integration of visual face and body information into identity representation at an early stage.