Figure 2.

Changes in subjective sleepiness and task performances in the visual discrimination task (5 msec task) after the injection of d-chlorpheniramine and placebo. No significant changes were detected in relative changes of SSS scores (B) in all treated groups. Ratios (post-inj. data / pre-inj. data) of RT (B) and accuracy (C) are shown for the treatment with placebo and d-chlorpheniramine (1 and 2 mg). A significant difference in both RT and the accuracy ratio was observed between the 2 mg and placebo groups (P<0.05). But no significant difference was observed between the 1 mg and placebo groups. The statistical significance of differences in each group were determined by ANOVA followed by Dunnett's multiple comparison test. ^*P<0.05 (vs placebo group); NS (not significant compared with placebo group).