Figure 3. Drug effects on learning rates.

(A) Learning rate for experienced-value learning, in stable and volatile periods, under MPH (purple) and PLA (green). (B) Learning rate for inferred-value learning, in stable and volatile periods, under MPH and PLA. (C) There was a significant interaction between drug and volatility for experienced-value learning, but not for inferred-value learning. (D) The interaction between drug and volatility was specific to experienced-value learning even for a sub-sample of participants who were keen inferred-value learners. Boxes = standard error of the mean, shaded region = standard deviation, individual datapoints are displayed, MPH = methylphenidate, PLA = placebo, * indicates statistical significance.