Practice effects on the less-affected upper extremity after stroke

Objective: To test the hypotheses that (1) adults who have had a stroke, using the less affected upper extremity (UE), improve performance of an aiming task with practice, and (2) compared with control subjects, stroke patients show less improvement in a complex condition. Design: Movement time (MT) and kinematic data were collected over practice. Comparisons were made between the less-affected UE of stroke patients and the same hand of controls. Setting: A human performance laboratory. Participants: A matched sample of right-handed adults, 10 with unilateral stroke and 10 nondisabled controls. Intervention: Practice of an aiming task in an easy and complex condition as defined by target width and distance between two targets. Main Outcome Measures: MT, peak velocity, and temporal phases of the trajectory. Results: Adults who had experienced a stroke had persistently longer MTs than control subjects; however, all participants achieved faster MTs with practice in both conditions. The absolute amount of time in each temporal phase decreased without a change in the relative times. Peak velocity increased only in the easy condition. Conclusions: Adults with stroke damage can improve motor performance of the less-affected UE with practice. Further study is needed to see if practice effects are permanent and generalizable. (C) 1999 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation.