ABSTRACT

Objective : Recent several investigations reported that impared motor function were detected on the ipsilateral as well as the contralateral upper extremity of the damaged hemisphere in patients with hemiparetic stroke. We investigated to determined the presence of ipsilateral motor deficits in serial reaction time task, and to infer the possible causes of the deficits.Methods : Eighteen stroke patients(10 right hemiplegia, 8 left hemiplegia) with fist-ever unilateral brain damage and the same number of normal control subjects were recruited, who were matched to sex and age. Subjects were assigned to press the matched button as quickly and accurately as possible, when one of four colored lights was displayed on computer screen(red, yellow, green, blue). We used three randomly order blocks and sequence order blocks respectively as motor paradigm of serial reaction time task. One block consisted of ten units that had ten stimulus. Reaction time was recorded during the tests.Results : A two-way ANOVA showed that there were statistically significant difference in a main effect of group(P<0.001), but not in a main effect of damaged side(P>0.05) and the interaction of group×damaged side(P>0.05) on the tests of random and block task paradigms. And group comparison within each sides of the upper extremities showed significant difference in all of two test(P<0.05)Conclusion : The findings provided by the experimental revealed that patients with unilateral brain damage have subtle deficits of the ipsilateral motor performance in serial reaction time task. We suggest that the ipsilateral upper extremity need to be carefully assessed in hemiparetic stroke patients in clinical neurorehabilitation.