Causal mapping of self-motion networks in the human brain

A comprehensive analysis of electrical brain stimulation during stereoelectroencephalography in 354 patients with drug-resistant epilepsy has shed light on the causal mechanisms behind vestibular self-motion perception. This study, which examined 19,708 stimulations at both high and low frequencies, generated 3,015 clinical responses to vestibular self-motion illusions.

These illusions encompassed a range of sensations from general vertigo and dizziness to more specific rotational and translational self-motion experiences. Notably, the insula, medial temporal regions, cingulate cortex, inferior frontal gyrus, and premotor cortices were identified as key sites for eliciting these perceptions, particularly when stimulation occurred outside epileptogenic and lesioned regions.

Network-level mapping using the Schaefer-Yeo atlas demonstrated that vestibular self-motion perception arises from activity within a distributed cortical network, with the strongest representation found in networks associated with attentional control and multisensory processing. This distributed network includes the salience/ventral attention, visual, and dorsal attention networks.

The findings offer causal evidence that such perception emerges from a complex interplay between these attentional and multisensory regions of the brain.

The results have significant implications for understanding human vestibular processing and could potentially inform clinical interventions for disorders characterized by altered self-motion perception, such as vestibular epilepsy and functional neurological disorders.