Self-face hallucination evoked by electrical stimulation of the human brain.

Abstract

Self-face hallucination (autoscopic hallucination or AH) has been reported in patients with widespread brain damage or retrospectively after epileptic seizures. The neural basis and the self-processing operations underlying AH remain unknown. We report the results of intracerebral electrical stimulations of the right medial occipitoparietal cortex (right precuneus and occipitoparietal sulcus) in 2 patients with epilepsy who underwent a stereo-EEG. Immediately after the onset of the stimulation, the 2 patients reported seeing their current own face, facing themselves, in their left visual field. Our study shows that the medial occipitoparietal junction has a key role in generating AH. This region has been shown to have a central role in various self-processing operations and especially in self-face recognition. Our observations further reveal that this region is involved in a visual representation of our own face, which is generated during the pathologic phenomenon of AH. This visual representation of our own face may be useful for self-face recognition and social cognition processes involving judgment of self-facial resemblance to others.