VISUAL MOTOR PERFORMANCE BEFORE AND AFTER CHEMOSURGERY OF THE BASAL GANGLIA IN PARKINSONISM

Abstract

The Bender Visual Motor Gestalt test was administered to 54 Parkinsonians before and after chemosurgery, and in a long range follow-up assessment. The group represents a consecutive sample of patients undergoing chemothalamectomy and chemopallidectomy. The test was evaluated according to methods described by Pascal and Suttel, with certain adaptations to make it more appropriate to the Parkinsonian population. In the pre-operative situation there is a high positive correlation between symptom severity and mental impairment on the one hand and impaired performance on the Bender-Gestalt on the other hand. Immediately post-operatively those undergoing surgery for the right hemisphere worsen in their overall performance, while the left hemisphere group shows no apparent changes. Long range scores reveal a return to preoperative functions for right hemisphere operates and improvement in overall performance for the left hemisphere group. The former group, moreover, demonstrates a mean increase in size of reproduction, although many individuals are found to compress their designs. The preoperative results were interpreted to indicate that in Parkinson''s Disease neurologic, mental and visual motor deficits are closely correlated. It was further suggested that results derived from the immediate and long range postoperative performance indicate differential functions for the hemispheres. An hypothesis was proposed that in visual motor performance, as evaluated by the Bender-Gestalt test, the right hemisphere plays a more significant role, first as concerns the neurophysio-logic bases for this activity, and second because post-surgical changes for this hemisphere group were more variable.