Atlas of intracranial electroencephalography complexity across cortical regions and global states of consciousness in the human brain.
PNAS nexus March 1, 2026 Lina Jeantin, Pierre Bourdillon, Marc Guenot et al.
Signal complexity in intracranial electroencephalography (iEEG) recordings from healthy brain tissue decreases with reduced consciousness, being highest during wakefulness and REM sleep and lowest under propofol anesthesia. Complexity is more variable during N2 and N3 sleep stages, and frontoparietal regions show the highest complexity during conscious states. Epileptic cortex exhibits lower complexity than healthy cortex during wake and REM sleep. A random forest classifier reliably classified sleep stages using complexity markers. These normative data support using iEEG signal complexity as a marker of physiological consciousness, cortical integrity, and sleep-stage detection.