Figure 4.

Global 5-HT depletion impaired both visual discrimination and subsequent reversal learning when 5,7-DHT was infused intracerebroventricularly (i.c.v.) prior to the initial acquisition of stimulus–reward contingencies (Expt. 1). (a) Sessions required to reach criterion (85% correct) in each stage for the preacquisition experiment. (b) Total trials completed until reaching training criterion for each phase. (c) Total number of errors committed up to and including the session in which criterion was reached. (d, e) Errors committed on (d) standard trials and (e) correction trials until reaching criterion. Fisher’s LSD analysis after significant main effect of treatment: ^*P < 0.05; ^**P < 0.01.