This review analyzes the literature on studies of states of pathological disorders (suppression) of consciousness based on the use of neuroimaging, electrophysiological, and other noninvasive methods for assessing nervous system activity. Problems of making diagnoses and prognosticating the recovery of patients with chronic disorders of consciousness are assessed. Neuroimaging, electrophysiological, physiological, and other correlates of chronic disorders of consciousness, such as the minimally conscious state and unresponsive wakefulness syndrome, are assessed. Pathways to resolving problems in diagnosis and prognostication of chronic disorders of consciousness are discussed. © 2021, Springer Science+Business Media, LLC, part of Springer Nature.