Cortical functional connectivity indexes arousal state during sleep and anesthesia.
NeuroImage May 1, 2020 Matthew I Banks, Bryan M Krause, Christopher M Endemann et al. 78 citations
Disruption of cortical connectivity likely contributes to loss of consciousness during sleep and general anesthesia, but the degree of overlap in mechanisms is unclear. Using intracranial recordings from five adult neurosurgical patients, alpha-band connectivity (measured by weighted phase lag index) was compared across natural sleep stages and propofol anesthesia. In wake states, alpha-band connectivity within the temporal lobe was dominant, a pattern largely unchanged in light sleep (N1, REM) and sedated states. Transitions into states of reduced consciousness (deep sleep N2/N3 and anesthesia-induced unresponsiveness) showed dramatic shifts, with dominant connections moving to prefrontal cortex. The findings suggest common mechanisms of loss of consciousness in sleep and anesthesia.