Figure 5. Effects of the ketanserin challenge in the 16-arm radial maze showing effects on error rates for working memory (A) and reference memory (B) at three different ketanserin doses (0.5, 1, and 2 mg/kg). Data represent means and SEs, with values for males and females combined because of the absence of an interaction of treatment × sex. In (A), ANOVA indicated a main effect of CPF treatment (p < 0.0001) and an interaction of CPF × ketanserin dose (p < 0.0001). In (B), both terms were also significant (p < 0.0001 and p < 0.002). Because of the interaction of the two treatments, separate analyses were then conducted for the effects of ketanserin in the control and CPF-treated groups. For both measures, ketanserin had no significant effect in the controls, whereas it elicited significant increases in errors in the CPF group (p < 0.0001 for A; p < 0.002 for B). : *Ketanserin doses that elicited significant increases in errors.