Common and distinct brain networks of autoscopic phenomena.
NeuroImage. Clinical – January 01, 2021
Source: PubMed
Summary
Autoscopic phenomena (AP), including out-of-body experiences (OBE), affect about 27% of neurological patients. A study involving 26 individuals revealed that all AP forms share a common brain network at the temporo-parietal junction. However, each type activates distinct networks: OBE connects to the angular gyrus and right precuneus, while autoscopic hallucinations engage the inferior temporal gyrus and cerebellum. Heautoscopy involves the left inferior frontal gyrus and insula. This highlights how bodily self-consciousness intertwines with multisensory processing in the brain.
Abstract
Autoscopic phenomena (AP) are illusory own body reduplications characterized by the visual perception of a second own body in extrapersonal space, and include three main forms: autoscopic hallucination (AH), heautoscopy (HAS) and out-of-body-experience (OBE). Past research showed that lesions were heterogeneously distributed and affected many different brain regions within and across patients, while small case series suggested that AP lesions converge in temporo-parietal and parieto-occipital cortex. As only few studies investigated each form of AP separately, it remains unknown whether the three AP are characterized by common and distinct brain mechanisms. Here, we applied lesion network analysis in 26 neurological AP patients and determined their common and distinct functional connectivity patterns. We report that all localize to a single common brain network at the bilateral temporo-parietal junction, further associated with specific patterns of functional connectivity, defining each type of AP. OBE resulted from a brain network connected to bilateral angular gyrus, right precuneus, and right inferior frontal gyrus, differing from AH with a brain network connected to bilateral precuneus, inferior temporal gyrus, and cerebellum. HAS resulted from a brain network connected to left inferior frontal gyrus, left insula and left parahippocampus. The present data identify the temporo-parietal junction as the common core region for AP and show that each form of AP recruits additional specific networks, associated with different sensorimotor and self-related sub-networks.