Fig. 5. Comparison of poststimulus power in frontal cortex at three concentrations of isoflurane. Power is calculated for the 2.5- to 20-Hz frequency band and expressed as the ratio of instantaneous power to power at baseline. Baseline is taken from the first 200 ms before burst onset. Flash is administered at time zero. Heavy line shows average power from 10 animals; lighter lines indicate ±SD.