Dr. Michele York, under the mentorship of Dr. Harvey Levin, Director of Research of Baylor College of Medicine's (BCM) Physical Medicine and Rehabilitation Department and Professor of Psychiatry and Neurosurgery, and Dr. Robert Grossman, the Chairman of BCM's Neurosurgery Department, will more effectively evaluate the long-term cognitive effects of deep brain stimulation (DBS) for the treatment of Parkinson's disease (PD). The scientific objective of the proposed research plan is to more clearly understand the relationship between the frontostriatal neural circuitry affected by DBS and PD and cognitive functioning. The clinical objectives of the proposed research plan include improving upon the evaluation of outcome by improving cognitive diagnostic techniques, clarifying the clinical criteria for surgical selection, and incorporating analysis of post-operative magnetic resonance imaging (MRI) findings. To achieve these aims, Dr. York will compare the executive functioning of patients undergoing staged bilateral subthalamic (STN) and globus pallidus (GPI) DEIS to patients who receive the best medical management for the treatment of PD on verbal fluency measures administered under conditions of set shifting and attentional control and working memory measures, which are cognitive processes dependent on the functional integrity of frontostriatal circuitry. The relationship between DBS electrode placement and performance on these frontostriatal neuropsychological tasks will also be investigated. The objectives of the training program are to acquire practical and technical skills that will aid Dr. York in developing her career, specifically in the areas of neurosurgical interventions and neurological evaluations of PD, structural and functional neuroimaging, and the neuroscience of PD. This training will provide Dr. York with a better understanding of the cognitive deficits in PD and the mechanisms and consequences of emerging interventions for the treatment of this neurological disease. The training activities during the award period will consist of 3 major components: 1) Didactics through coursework, technical training seminars, rounds, and observation, 2) Supervisory Guidance through regularly scheduled meetings with mentors and an Advisory Committee, and 3) Instruction in the Responsible Conduct of Research. Dr. York will gain the necessary knowledge to attain her long-term career goal of working as an independent clinical researcher by acquiring the background and skills in neuroscience, neuroimaging, and grant preparation needed to write a ROI proposal to adapt these cognitive tasks to a functional imaging setting to further elucidate the neural mechanisms of PD and DBS.