Fig. 3.

Enhancement of PR performance following systemic amphetamine administration in the absence of generalised locomotor hyperactivity. a Breakpoint values of C57Bl/6 mice (n = 18) administered 0.1 or 1.0 mg/kg d-amphetamine versus vehicle. b Reward collection latency and c post-reinforcement pause are unaffected by amphetamine administration. d–f Amphetamine differentially affects IR beam break rates in the front and rear zones of the behavioural arena and the magazine. g Amphetamine increases the rate of touches at non-target response locations. h Amphetamine has no effect on total response time. i Amphetamine has no effect on inter-response interval (*p < 0.05; ns not significant)