Strange-face illusions during inter-subjective gazing

► The study extends previous research on mirror-gazing to gazing at another person. ► Inter-subjective gazing increases strange-faces with respect to mirror-gazing. ► Strange-faces are dissociative of the subject's self who loses self-agency. ► Inter-subjective gazing produces synchrony of event-related responses to illusions. ► Synchrony of responses actually reflects synchronicity of illusion contents.