Shown are pairwise overlays of the statistical parametric maps for the contrasts explore > exploit (‘overall’ in green), directed > exploit (‘directed’ in red), and random > exploit (‘random’ in blue) over all drug conditions. While the first contrast is based on a binary choice classification according to which all choices not following the highest expected value are explorations, the other two contrast are based on a trinary choice classification, which further subdivides explorations into choices following the highest exploration bonus (directed) and choices not following the highest exploration bonus (random). All activation maps thresholded at p<0.05, uncorrected for display purposes. R: right.