Depth Electrode Studies of Thalamus and Basal Ganglia

Abstract

The electrophysiological investigation of patients with dyskinesias undergoing surgical treatment has contributed information in two major areas. Previous reports by this group, and others,^{3,4,9-11,14,19-21} have shown that electrical stimulation of regions in the diencephalon and basal ganglia can be utilized as an additional method for the appropriate selection of a surgical target. The demonstration that a particular site on stimulation influences the patient's abnormal movement pattern has been used in the clinical selection of a lesion where precise anatomical localization may be in doubt or where several possible locations might be considered, i.e., globus pallidus versus the ventral lateral nucleus of the thalamus. Aside from the direct therapeutic considerations, physiological studies utilizing depth electrodes might be expected to contribute information regarding the mechanisms of tremor and other types of abnormal motor movement. An opportunity is also present to permit a study of some diencephalic, basal ganglia, and cortical interrelationships.