(a) Mean duration (1SD) of stepping movements during physical execution and mental simulation conditions on affected and unaffected sides in the subgroups of patients with a left hemispheric (LHL) and a right hemispheric (RHL) lesion. Note that the RHL subgroup, in contrast to the LHL subgroup, had longer movement times during the imagination condition. (b) Corresponding imagination/execution time ratios for dominant and nondominant sides in each subgroup of patients with an LHL or an RHL. Dotted line indicates temporal congruence of 1 to 1.