Average trial time data are shown for the two participants who were unable to complete all 10 blocks of training on each day of acquisition (one from the “off” levodopa group, shown on top, and one from the “on” levodopa group, shown on the bottom). Similar to Figure 3, average trial time for each block of the acquisition period (Days 1–3) and the two retention sessions (Day 5 and Day 12) are shown. Note that most acquisition days have less than 10 blocks, indicating incomplete acquisition.