Brain networkmotif topographymay predict emergence fromdisorders of consciousness: A case series

Abstract

Neuroimagingmethods have improved the accuracy of diagnosis in patientswith disorders of consciousness (DOC), but novel, clinically translatable methods for prognosticating this population are still needed. In this case series, we explored the association between topographic and global brain network properties and prognosis in patientswith DOC.We recorded high-density electroencephalograms in three patients with acute or chronic DOC, two ofwhomalso underwent an anesthetic protocol. In these two cases, we compared functional networkmotifs, network hubs and power topography (i.e. topographic network properties), aswell as relative power and graph theoretical measures (i.e. global network properties), at baseline, during exposure to anesthesia and after recovery from anesthesia.We also compared these properties to a group of healthy, conscious controls. At baseline, the topographic distribution of nodes participating in alphamotifs resembled conscious controls in patients who later recovered consciousness and high relative power in the delta band was associated with a negative outcome. Strikingly, the reorganization of networkmotifs, network hubs and power topography under anesthesia followed by their return to a baseline patterns upon recovery from anesthesia,was associatedwith recovery of consciousness. Our findings suggest that topographic network propertiesmeasured at the single-electrode levelmight provide more prognostic information than global network properties that are averaged across the brain network. In addition, we propose that the brain network's capacity to reorganize in response to a perturbation is a precursor to the recovery of consciousness in DOC patients.