Repetitive Transcranial Magnetic Stimulation Over the Temporoparietal Junction Influences Distinction of Self From Famous but Not Unfamiliar Others

Neuroimaging and studies using repetitive transcranial magnetic stimulation (rTMS) have shown that a hierarchically organized neural network comprising the right temporoparietal junction (TPJ) and the prefrontal cortex is involved when discriminating one's own face from other faces. Less clear, however, is the role of attention in self-other distinction. Accordingly, the present study aimed at investigating the role of the right TPJ in self-other and other-other discrimination by using low-frequency repetitive TMS while controlling for attention. We tested 10 healthy right-handed subjects using a video task, which comprised morphings of famous, unfamiliar, and the subjects' own faces that gradually transformed into each other. Reaction time (RT) was measured by pushing a mouse button once a change of identity was recognized. Subjects received rTMS over the right TPJ, sham stimulation, or no stimulation, separated by 1 week. rTMS over the right TPJ influenced the distinction between one's own and a famous face. Specifically, subjects needed more features to identify the famous face after rTMS to the right TPJ compared with the control conditions. No rTMS effect was observed when subjects had to distinguish between their own and unfamiliar faces, nor did rTMS affect attention. This suggests that the right TPJ is involved in self-other distinction, specifically if the other's face is familiar to the subject.