In contrast, explicit instruction had a detrimental effect on learning in the subjects with stroke. This can be seen in Figure 5.15B, which shows that the subjects with stroke who received explicit information (solid line) had less improvement in reaction time compared with subjects with stroke who did not receive explicit information (dashed line). The finding that explicit instruction impairs implicit learning was also found for patients with basal ganglia stroke (Pohl & Winstein, 2004). In contrast, in patients with cerebellar stroke, explicit instruction improved implicit learning (Molinari et al., 1997). These results suggest that the impact of explicit instruction on implicit learning depends on a number of factors, including the type, timing, and meaningfulness of instructions, as well as the location of CNS pathology.