Sleep Profiles in REM Sleep Behavior Disorder

Inclusion Criteria: 1. Diagnosis of RBD as assessed by the International Classification of Sleep Disorders (ICDS) diagnostic criteria within 3 years 2. 40 yrs of age Exclusion Criteria: 1. Other significant neurological disorder 2. Untreated significant sleep apnea and/or current sleep apnea symptoms as assessed by the clinical investigator 3. Co-existent restless legs syndrome (RLS), as assessed by the ICDS diagnostic criteria for RLS 4. Cognitive impairment as determined by the Montreal Cognitive Assessment (MoCA) score of ≤ 23 5. Presence of depression defined as the Beck Depression Inventory (BDI) score \>20 6. Use of tricyclic antidepressants, MAO inhibitors or selective serotonin reuptake inhibitors since they may induce/worsen RBD, unless on a stable dose of medication for at least 8 weeks 7. Use of medications known to affect melatonin secretion, such as lithium, α- and β-adrenergic antagonists 8. Shift work, currently or within the prior 3 months 9. Travel through ≥ 2 time zones within 60 days prior to the screening