Evoked Alpha Power is Reduced in Disconnected Consciousness During Sleep and Anesthesia
Scientific Reports November 5, 2018 Matthieu Darracq, Chadd M. Funk, Daniel Polyakov et al. 49 citations
Sleep and anesthesia alter conscious experience, which can be absent (unconsciousness) or take the form of dreaming where sensory stimuli are not incorporated (disconnected consciousness). Using transcranial magnetic stimulation-electroencephalography over parietal regions, evoked alpha power (8-12 Hz) decreased during disconnected consciousness in rapid eye movement sleep and ketamine anesthesia compared to wakefulness. In unconscious states of propofol anesthesia and non-rapid eye movement sleep, evoked low-gamma power (30-40 Hz) decreased compared to wakefulness or disconnected consciousness. These findings, confirmed with dream reports from serial awakenings, suggest suppression of evoked alpha activity may mark sensory disconnection.