Fig. 2. Population data for all recording sites when cranial isoflurane was 1.1 ± 0.3% and torso isoflurane was 0.3 ± 0.1%. There was a significant decrease in one or more of total, δ, θ, and α power in all sites. #P < 0.01 prestimulus value compared with poststimulus value. *P < 0.05 prestimulus value compared with poststimulus value. Electroencephalographic (EEG) power is expressed as μV2. Note that the Y scales (EEG power) differ among the various graphs. MRF = midbrain reticular formation.