RecruitingClinical trialCognitive Decline Following Deep Brain Stimulation: A DBS-fMRI StudyThe objective of this research study is to understand how Deep Brain Stimulation (DBS) targeting the subthalamic nucleus (STN) affects cognitive networks in the brain, potentially leading to cognitive decline in patients with Parkinson's Disease (PD). A total of 55 participants with PD who have undergone DBS surgery will be recruited from MUSC's Clinical DBS Program. Participants will attend two post-DBS visits: a 3-hour visit for consent, demographic, and cognitive assessments, and a 3-hour DBS-MRI visit to evaluate brain network connectivity with stimulation ON and OFF. These findings will help improve patient selection for surgery and optimize the selection of stimulation targets that minimize undesirable cognitive side effects.