Mesoscopic physiological interactions in the human brain reveal small-world properties and associations with behavior

Abstract

Cognition depends on rapid and robust communication between neural circuits spanning different brain areas. Here we investigated the mesoscopic network of cortico-cortical interactions in the human brain in an extensive dataset consisting of 6,024 hours of intracranial field potential recordings from 4,142 electrodes in 48 subjects. Communication between brain areas was evaluated in a pairwise fashion and at the network level across different frequency bands. The interaction networks were validated against known anatomical measurements and neurophysiological interactions in humans and monkeys. The resulting human brain interactome is characterized by a broad and spatially specific, dynamic, and extensive. The physiological interactome revealed small-world properties, which we conjecture might facilitate efficient and reliable information transmission. The interaction dynamics correlate with the brain sleep/awake and also with natural behaviors. These results constitute initial steps towards understanding how the interactome orchestrates cortical communication and provide a reference for future efforts to assess how dysfunctional interactions may lead to mental disorders.