Fig.. 3.

Acquisition of nose-poke responding for 0.03 mg/kg/inj racemic (a, n = 9) and S-α-PVP (b, n = 10) and 0.3 mg/kg/inj R-α-PVP (c, n = 8). Lines with symbols are active responses. Lines without symbols are inactive responses. Solid symbols are for days during which active responses were significantly different (p < 0.05) from inactive responses on that day. For R-α-PVP the main effect of response was significant, but not the response x day interaction. The bottom panels show extinction for those rats who maintained catheters through acquisition and dose-effect (Fig. 4) testing (d racemic n = 7, e S-α-PVP n = 8, f R-α-PVP n = 6). Symbol designations are the same as for acquisition. Each point is the mean ± SEM.