Wisconsin card sorting test variables in relation to motor symptoms in Parkinson's disease

The Wisconsin Card Sorting Test, a standard test for the assessment of exec utive function and free of a motor component, was employed for the assessme nt of 37 nondemented patients with idiopathic Parkinson's Disease and 37 ma tched normal controls. The symptoms of the patients were clinically assesse d by means of the Unified Parkinson's Disease Rating Scale, which yielded s cores for the cardinal symptoms of the disease as well as a total motor sco re. The Wisconsin Card Sorting Test was administered in all subjects in its original form (128 cards), and it was scored to yield 16 measures accordin g to the instruction of the Wisconsin Card Sorting Test revised manual. Pat ients with Parkinson's Disease had significantly lower scores an the follow ing test variables: number of trials administered, perseverative responses, percent perseverative responses, and failure to maintain set. The correlat ions between the last three variables and total motor score were statistica lly significant. Of the four cardinal symptoms of the disease, only rigidit y correlated significantly with the number of perseverative responses and p ercent perseverative responses. These findings provide a clue that the lowe r performance of these patients on certain variables of the Wisconsin Card Sorting Test may be related to the process of the disease.