Change in the sleep/wake pattern as determined by EEG/EMG at 7 days after sciatic nerve ligation. The total mean times (sec/h) in wakefulness (A), NREM sleep (B) and REM sleep (C) were determined by EEG/EMG recording for 24 hrs. Each point represents the mean ± SEM (n = 11). Student’s t-test was performed. *p < 0.05, **p < 0.01 and ***p < 0.001 compared with the sham group.