Figure 3.

Delta, theta, and alpha EEG power changes induced by tramadol (5, 15 and 45 mg/kg i.p.) during (A) wakefulness, and (B) non-rapid eye movement sleep (NREMS) with the calculated SEM for each hour. EEG power data were averaged for each hour after administration of vehicle or tramadol at the beginning of the passive phase. The # and * signs indicate significant post hoc results (p < 0.05) compared to vehicle in case of the 15 and 45 mg/kg tramadol-treated groups, respectively. Data are presented as SEM (n = 8 rats/group).