Effect of SB-215505 (1.0 mg kg−1 i.p.) on different vigilance states in conscious, freely moving rats. Time of W in each 15 min period within the first 2 h after treatment (a). Time of W (b), SWS-1 (c), SWS-2 (d), IS (e) and PS (f) per hour within the first 5 h after treatment. All columns represent mean values (±s.e.m., n=6). *Significant effect of SB-215505 compared to vehicle, P<0.05.