TY - JOUR T1 - A Transition in Brain State during Propofol-Induced Unconsciousness JF - The Journal of Neuroscience JO - J. Neurosci. SP - 839 LP - 845 DO - 10.1523/JNEUROSCI.5813-12.2014 VL - 34 IS - 3 AU - Eran A. Mukamel AU - Elvira Pirondini AU - Behtash Babadi AU - Kin Foon Kevin Wong AU - Eric T. Pierce AU - P. Grace Harrell AU - John L. Walsh AU - Andres F. Salazar-Gomez AU - Sydney S. Cash AU - Emad N. Eskandar AU - Veronica S. Weiner AU - Emery N. Brown AU - Patrick L. Purdon Y1 - 2014/01/15 UR - http://www.jneurosci.org/content/34/3/839.abstract N2 - Rhythmic oscillations shape cortical dynamics during active behavior, sleep, and general anesthesia. Cross-frequency phase-amplitude coupling is a prominent feature of cortical oscillations, but its role in organizing conscious and unconscious brain states is poorly understood. Using high-density EEG and intracranial electrocorticography during gradual induction of propofol general anesthesia in humans, we discovered a rapid drug-induced transition between distinct states with opposite phase-amplitude coupling and different cortical source distributions. One state occurs during unconsciousness and may be similar to sleep slow oscillations. A second state occurs at the loss or recovery of consciousness and resembles an enhanced slow cortical potential. These results provide objective electrophysiological landmarks of distinct unconscious brain states, and could be used to help improve EEG-based monitoring for general anesthesia. ER -