Local field potential dynamics during ketamine anesthesia and recovery. (A) Behavioral response. (B) Average spectrograms across channels in the primary somatosensory cortex (S1) in a single recording session. (C) Average spectrograms in secondary somatosensory cortex (S2) in the same session. (D) Average spectrograms in ventral premotor area (PMv) in the same session. (E) Change of the power in the slow-delta (0.5 to 4 Hz), theta (4 to 7 Hz), alpha (7 to 12 Hz), low beta (12 to 18 Hz), high beta (18 to 30 Hz), and gamma (30 to 65 Hz) for S1 (red) and PMv (blue). Power was normalized to the preanesthetic baseline using Z-scores. Bars on top of each graph indicate statistically significant difference compared to the preanesthetic baseline (P < 0.05, ANOVA and post hoc Bonferroni test). Propofol was infused for 60 min (1,800 to 5,400 s, gray solid lines in A–E). Loss of consciousness (LOC) is shown with a black arrow and dotted lines, return of consciousness (ROC) with a purple arrow and dotted lines, and performance return with an orange arrow and dotted lines in A–E. (F) Average power spectrum across channels in a single recording session in S1. The spectra are shown during wakefulness (black, averaged over 1 min before the start of ketamine infusion), anesthesia (red, averaged over 1 min immediately before the end of ketamine infusion), LOC (blue, averaged over 1 min after LOC), and performance return (cyan, averaged over 1 min after performance return). (G) Average power spectrum in S2. (H) Average power spectrum in PMv.