Physiologic Effects of Deep Brain Stimulation in Patients with Parkinson’s Disease

Robert Chen, MA, MBBChir, MSc, FRCPC
Toronto Hospital, Western Division

Dr. Robert Chen is part of the deep-brain-stimulation (DBS) team at Toronto Western Hospital, one of the early North American centers using this surgical procedure to ameliorate the symptoms of PD. As he presented at the recent Movement Disorders congress, they used transcranial magnetic stimulation (TMS) to measure DBS effects on motor cortex excitability in six of their patients and found significant changes with stimulation using electrodes in the internal globus pallidus. This, they concluded, better explained the antidyskinetic effects of pallidal stimulation. They hope to provide more understanding of the adnormal function of the basal ganglia (in which the pallidum is located) in PD patients.