Figure 3.

Results of the psychophysical experiment. (A) Performance accuracy. Dotted line indicates the level of chance performance (20%). A two-way ANOVA (5 expressions × 2 groups) on the percent correct scores produced a significant main effect of expressions (P < 0.001), but neither a significant main effect of group nor a significant interaction between expression and group (P-values > 0.4). One-sample t-tests on the percent correct scores showed that the accuracy for each facial expression was significantly above chance (P-values < 0.01). (B) Response time. The same two-way ANOVA on the response time produced a significant main effect of expression (P < 0.001), but neither the main effect of group nor the interaction between expression and group were significant (P-values > 0.1). Data are presented as the mean ± SEM of 14 subjects for each group.