Levodopa improves procedural motor learning in chronic stroke patients.

Rösser N, Heuschmann P, Wersching H, Breitenstein C, Knecht S, Flöel A

Abstract

OBJECTIVE: To test the hypothesis that administration of dopamine precursor levodopa improves procedural motor learning (defined as the ability to acquire novel movement patterns gradually through practice) in patients with residual motor deficits in the chronic phase after stroke (> or =1 y after stroke). DESIGN: A double-blind, placebo-controlled, randomized crossover design. SETTING: Neurology department in a German university. PARTICIPANTS: Eighteen patients with chronic motor dysfunction because of stroke (13 men, 5 women; age range, 53-78 y; mean time poststroke +/- SD, 3.3+/-2.1 y). INTERVENTION: Patients received 3 doses of levodopa (100mg of levodopa plus 25mg of carbidopa) or placebo before 1 session of procedural motor learning. MAIN OUTCOME MEASURES: Procedural motor learning performed by using the paretic hand assessed by using a modified version of the serial reaction time task with a probabilistic sequence. The primary outcome measure was the difference in reaction times between random and sequential elements. RESULTS: Levodopa significantly improved our primary outcome measure, procedural motor learning, compared with placebo (P