LAUSR

OBJECTIVE To explore motor performance on 2 different cognitive tasks during robotic rehabilitation in which motor performance was longitudinally assessed. DESIGN Prospective study. SETTING Rehabilitation hospital. PARTICIPANTS Patients (N=22) with chronic stroke and upper extremity impairment. INTERVENTION A total of 640 repetitions of robot-assisted planar reaching, 5 times a week for 4 weeks. MAIN OUTCOME MEASURES Longitudinal robotic evaluations regarding motor performance included smoothness, mean velocity, path error, and reach error by the type of cognitive task. Dual-task effects (DTEs) of motor performance were computed to analyze the effect of the cognitive task on dual-task interference. RESULTS Cognitive task type influenced smoothness (P=.006), the DTEs of smoothness (P=.002), and the DTEs of reach error (P=.052). Robotic rehabilitation improved smoothness (P=.007) and reach error (P=.078), while stroke severity affected smoothness (P=.01), reach error (P<.001), and path error (P=.01). Robotic rehabilitation or severity did not affect the DTEs of motor performance. CONCLUSIONS The results provide evidence for the effect of cognitive-motor interference on upper extremity performance among participants with stroke using a robotic-guided rehabilitation system.