Clinical assessments can only offer a snapshot of daily life with Parkinson's Disease, while wearable devices can offer immensely more information that can improve the understanding of this disease. With recent advancements in technology, investigators are now able to use watch-like devices to more effectively measure the symptoms of Parkinson's Disease outside of the doctor's office. The present study is designed to evaluate the usability, applicability, and interpretability of an electronic VA Patient Motor Diary (eON-OFF), MC10 BioStampRC actigraphy sensor, APDM actigraphy sensor and the GENEActiv Watch in persons with Parkinson's Disease. There is no placebo/control group.

The proposed study will be comprised of at least four sessions in the Spivack Center (Rm. X-140) on separate days (not counting recruitment, screening, or consent activities), each lasting approximately 1-2 hours. Subjects will commence a 1-week testing period during which they will wear the 3 actigraphy devices in their normal schedule and daily environment. On Days 2, 3, 4, and 5, subjects will use the eON-OFF motor diary application to select their current Parkinson state (e.g. "on", "off"). ON and OFF states are subjective measures identified by subjects, and are commonly used words in Parkinson's Disease treatment and research to describe symptom states. Symptom severity is directly linked to medication effectiveness. "On" is when the medication is working and symptoms are not severe or troublesome. "Off" is when medication has worn off, and symptom severity increases. Subjects will also use the eON-OFF motor diary application to verbally record symptomology every 30 minutes while awake. Subjects will complete paper VA Patient Motor Diaries to record ON and OFF states on Day 2, Day 3, and Day 4. Subjects will then complete the outlined set of activities during Phase I in a second phase to take place approximately one month later. All questionnaires, training and interviews will be administered one-on-one by a trained research assistant. All UPDRS' will be administered by a clinician. Ideally, subjects will be administered the study activities on the days listed above, but they are allowed a flexibility of +/- 4 days for scheduling appointments.

Inclusion Criteria:

• Self-reported clinical diagnosis of Parkinson's disease consistent with the United Kingdom (UK) Parkinson's Disease Society Brain Bank Clinical Diagnostic Criteria.
• Self-reported ability to recognize their "wearing off" symptoms and confirmation that they usually improve after their next dose of Parkinson's disease medication.
• Parkinson's disease Hoehn & Yahr Stage less than or equal to III (assessed while the patient is "ON").
• Currently responding to L-Dopa therapy. On a stable dose of L-Dopa (or L-Dopa equivalent) of at least 300 mg total daily dose for at least 28 days prior to Day 1, in conjunction with a dopa decarboxylase inhibitor (e.g., L-Dopa/carbidopa or L-Dopa/benserazide) divided in at least 3 divided doses per day.
• 45-75 years old
• Able to understand and cooperate with study procedures and give informed consent.
• Evidence of a personally signed and dated informed consent document indicating that the subject has been informed of all pertinent aspects of the study
• Body Mass Index (BMI) of 17.5 to 35 kg/m2; and a total body weight of greater than or equal to 45kg.
• Native English speaker or demonstrated fluency in English.
• Normal or corrected-to-normal vision
• A score of greater than or equal to 26 on the Mini Mental State Examination (MMSE).
• A score of 49 on the Green Form of the WRAT-4 Word Reading Subtest (equivalent to 8th grade reading level)

Exclusion Criteria:

• Treatment with an investigational drug within 30 days of Day 1 of study activities.
• Diagnosis of moderate to severe alcohol use disorder within 6 months of the screening as disclosed by the subject
• Employees, student, or advisee of the Principal Investigator
• History of head injury with clinically significant sequelae (e.g. loss of consciousness for greater than 15 minutes).
• DSM-V diagnosis of current, or history of, neurological disease (except for Parkinson's disease), Schizophrenia Spectrum or Other Psychotic disorders, or Bipolar and Related Disorders as disclosed by the subject.
• Subjects with cardiac pacemakers, electronic pumps, or any other implanted medical devices, including deep brain stimulation devices.
• Women of childbearing age will be required to undergo a pregnancy test to rule out a possible pregnancy.
• Allergy to adhesives or silicone

Individuals diagnosed with Parkinson's disease.