Implicit Motor Learning after Unilateral Stroke Using Serial Reaction Time Task

Abstract

Introduction: Motor skills and learning after stroke are of a great importance. This study aimed at studying implicit learning in unilateral stroke patients using affected hand and comparison with normal subjects. Methods: A serial reaction time task by using a software was applied for studying implicit motor learning in 15 stroke patients and 15 matched normal subjects. In this task 4 squares with different colors appeared on the monitor and subjects were asked to press its defined key immediately after observing it. In the first day subjects practiced 8 motor blocks (4 patterned blocks, then 2 random blocks and finally 2 patterned blocks). The next day subjects practiced a retention test consisted of 2 patterned blocks. Subjects were not provided with any explanation about the sequence of squares. All subjects were right handed and impaired hand in patients was right side and they practiced with their impaired hand. Results: Task performance of patients was slower than normal subjects. Age, sex and educational level had no significant effects on task performance. Block time differences of second block with fourth, eight and tenth blocks (next day) were significant in both groups. Conclusion: Similar motor learning (defined as stable decrease of block times) in stroke patients and normal subjects shows the capability of stroke patients in implicit motor learning during using the affected hand and this is not affected by age, sex and educational level.