The objective of this research study is to identify brain biomarkers using MRI scans that can predict an individual's response to Deep Brain Stimulation (DBS). A total of 55 participants with Parkinson's Disease planning to undergo DBS will be recruited from MUSC's Clinical DBS Program. Participants will undergo two visits which include a 2.5-hour pre-DBS questionnaire and MRI scanning visit, and a 3.5-hour post-DBS cognitive assessment visit. In addition control participants without Parkinson's Disease will be recruited to undergo MRI scanning and cognitive assessments.