The neural dynamics of current and past self-face perception: Challenging the privilege access hypothesis

Setting apart the neural properties of familiarity for both self and others' faces helps deepen our understanding of the cognitive, developmental, and theoretical dimensions of social dynamics and human identity. Motivated by this goal, we conducted a multivariate cross-classification EEG experiment where we tested whether individuals represent their own face as similar to other highly familiar faces or code self-faces through different familiarity processes. We compare the representational dynamics for self and other faces in both their current and past versions. Participants were presented highly variable faces of four familiarity categories (self, parent, close-friend and unknown) in two versions across lifespan: current and past images, which were taken 10 years ago. Linear discriminant classifiers were trained and tested on EEG patterns to discriminate familiar and unfamiliar faces. Time-resolved classification revealed that the neural representations of familiarity emerge before 200 msec post-stimulus onset and remains significant until 600 msec, independently of familiarity level and age. Further, our findings show that the temporal dynamics of familiarity is similar for self-faces and other highly familiar faces. Our study provides new insights into how the brain represents self-identity and suggest that important aspects of self-recognition, such as the familiarity of self-face, is supported by learning processes rather than privilege introspective mechanisms.