Figure 3. Drug effects on perceptual decision making.
No drug effects were observed on the signal strength (A, stimulus motion orientation) or the response speed (B). In line with no difference in accuracy, perceptual sensitivity d’ did not differ between groups (C). Median confidence ratings (D) showed no difference revealing that there was no bias in the average rating behaviour between groups. These findings suggest that noradrenaline blockade selectively boosts metacognitive sensitivity in the absence of any effect on perceptual decision making. mean ±1 SEM; n.s. p>0.10.