Striatal and Extra-Striatal Cholinergic Terminal Density in LRRK2-PD Mutation

Inclusion Criteria: 1. Male or Female, age 45 years and over. 2. Diagnosis of PD based on the United Kingdom Parkinson's Disease Society Brain Bank Diagnostic Research Criteria (Hughes et al., 1992). 3. Presence of LRRK2 mutation as confirmed by referral from UM Movement Disorders clinic, medical record review, or participation in the PDGENEration study. Exclusion Criteria: 1. Evidence of atypical parkinsonism. 2. Contra-indications to MR imaging including but not limited to pacemakers, aneurysm clips, intraocular metal, cochlear implant, or severe claustrophobia. 3. Evidence of large vessel stroke or mass lesion on MRI. 4. Regular use of typical anti-cholinergic drugs or cholinesterase inhibitors. 5. History of deep brain stimulation surgery. 6. Pregnant or nursing. 7. Suicidal ideation, as indicated by a response of 2 or 3 on question 9 of the Beck Depression Inventory. 8. Cognitive impairment that results in the inability to give consent, as demonstrated by the Decision Making Capacity Tool. 9. Any other condition or criterion that would preclude safe and meaningful participation in the study.