Effects of Exenatide on Motor Function and the Brain

Inclusion Criteria: * patients clinically diagnosed with Parkinson's disease (PD) through use of the UK PD brain bank diagnostic criteria * early stage PD patients within 5 years of diagnosis who have never taken Exenatide for any reason * PD patients with a Hoehn and Yahr stage less than or equal to 2 when on medication * patients able and willing to sign informed consent. Exclusion Criteria: * individuals who have any type of implanted electrical device (such as a cardiac pacemaker or a neurostimulator) * individuals with a certain type of metallic clip in the body (i.e., an aneurysm clip in the brain) * claustrophobia * women who are or might be pregnant and nursing mothers. Pregnancy tests will be carried out for each female subject prior to the MRI scan. * psychiatric disorders or dementia * other neurologic and orthopedic problems that impair hand movements and walking * individuals actively participating in another trial of a device, drug or surgical treatment for Parkinson's disease * individuals who have a history metalworking involving cutting processes such as grinding, filing, shaving, and threading, will need radiological clearance to participate in this study. Specifically, individuals who report a history of metalworking will be referred to Radiology at Shands University of Florida(UF) for an orbitofrontal x-ray. * individuals who have sustained an eye injury involving metal will also be referred to Radiology at Shands UF for an orbitofrontal x-ray. * prior stroke or brain tumor * cognitive impairment as assessed by a Montreal Cognitive Assessment score \< 23 * individuals unwilling to comply with the study procedures * history of gallstones, digestion problems (such as gastroparesis), severe gastrointestinal disease, history of pancreatitis, a thyroid tumor or cancer, pancreas tumor, or kidney problems * severely impaired renal function with creatinine clearance less than 30 ml/min * hyperlipidemia defined as more than two times the upper limit of normal * body mass index less than 18.5 * previous exposure to Exenatide * diabetes