The cardinal motor features of Parkinson's disease (PD) include bradykinesia, rest tremor, and rigidity. Though non-motor features have been recognized for centuries, only recently has the prevalence and impact of non-motor symptoms become the focus of intense study. Disturbances of sleep are among the most common non-motor manifestations of PD; approximately two-thirds of PD patients experience sleep dysfunction of some kind. Given that sleep contributes to the regulation of many physiological processes, sleep disturbance has a significant impact on quality of life in PD, and places high strain on caregivers. Though numerous symptomatic therapies exist, the treatment of sleep disorders in PD is limited by a lack of adequately powered, randomized studies providing high quality evidence. Although deep brain stimulation (DBS) is primarily used to treat PD motor symptoms and reduce the need for dopaminergic medications, several studies have shown that DBS provides benefit for non-motor symptoms, including sleep disturbance. Few studies have used an objective measure to assess the impact of DBS on sleep in PD, and none have done so by studying sleep in the home environment. Existing studies have largely been limited to a single night of sleep recording in a sleep lab. Furthermore, no studies have assessed sleep both on and off medication, before and after DBS implantation. This study will enroll patients undergoing evaluation for DBS implantation. Sleep will be assessed before DBS implantation, both while patients continue their usual medication regimen and while withholding medications. After DBS implantation and programming, sleep will again be assessed with stimulation on, both while continuing medications and subsequently while withholding medications.

Inclusion Criteria:

Research subjects must be willing and able to do the following:

• Be able to learn to use and maintain a wristband-style sleep monitor
• Wear a wristband-style sleep monitor for two weeks
• Be able to learn to use and maintain a headband sleep monitor
• Wear a headband sleep monitor for two weeks
• Log daily routine events, such sleeping, eating, and medication regimens for the two-week study period
• Withhold dopaminergic medications after 5:00pm for three consecutive nights

Exclusion Criteria:

Subjects will be excluded if they:

• Carry a diagnosis of dementia (e.g., Parkinson's Disease Dementia or Dementia with Lewy Bodies)
• Currently use or recently (within past 30 days) used a sedative-hypnotic agent for sleep (e.g., Zolpidem, Suvorexant, Eszopiclone)
• Fulfill criteria or carry a diagnosis of a circadian sleep-wake rhythm disorder, as defined by the International Classification of Sleep Disorders, Third Edition

Patients undergoing evaluation for DBS candidacy are eligible to participate in this study. Those deemed appropriate for DBS implantation and who undergo bilateral DBS will complete the second (post-operative) phase of the study. Candidacy for DBS implantation will be determined by the treating team, which includes a neurologist, neurosurgeon, neuropsychologist, neuro-radiologist, and palliative care physician. Decision to participate in the study will have no bearing on DBS candidacy. Patients are eligible to participate in this study regardless of device being implanted.