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Cortical Stimulation for Movement Disorders
S. Palfi
in the STN and GPi using unitary neuronal record- ings. All these functional effects were similar to those reported for deep brain stimulation in STN or GPi, using intraparenchymal electrodes. Most importantly, the present series of experiments were conducted as a pre-clinical study assessing the behavioral benefit in a chronic MPTP primate model in which dopamine depletion was progressive and regularly documented using 18-F-dopa Pet-scan. The data also suggest that motor cortex stimulation was more effective in se- verely disabled animals implying therapeutic poten- tial for advanced parkinsonian patients. Moreover, the major advantage of such a surgical approach is the simplicity and safety of the procedure entailing an epidural electrode that can be introduced without a deep brain stereotaxic surgery.
A novel concept in movement disorders has emerged postulating that the cortex may be implicated in the genesis of motor symptoms. Further experimental and clinical studies in Parkinson’s disease showed that motor cortex may also pattern abnormal rhythmic activity in the basal ganglia that underlies the ob- served motor symptoms. Here, we describe the use of electrical interference of motor cortex in a primate model of Parkinson’s disease. Using high-frequency trains of pulses, motor cortex stimulation signifi- cantly reduces akinesia and bradykinesia in MPTP baboons. This behavioral benefit was associated with an increase metabolic activity in the supplementary motor area using 18-F-deoxyglucose Pet-scan, nor- malization of mean firing rate in internal globus pal- lidus (GPi) and subthalamic nucleus (STN) and re- duction of synchronized oscillatory neuronal activities
