Vibrotactile Coordinated Reset (vCR) for the Treatment of Advanced Parkinson's Disease Patients Who Have Previously Received vCR Stimulation

This scale measures motor ability within Parkinson's patients. For part 3, the scales minimum values is 0 and max value is 132. Higher scores indicate more impaired motor ability, while lower scores indicate less impaired motor ability. A score of 0 indicates no motor impairment.

LEDD is calculated as a daily sum of levodopa in each Parkinson's medication

The PD Quality of Life Questionnaire-39 (PDQ-39) is a self-report questionnaire that examines health related difficulties specific to PD in eight quality of life categories within the last month. Items are grouped into eight scales that are scored by expressing summed item scores as a percentage score ranging between 0 and 100, with higher % indicating more health problems.

The Freezing of Gait questionnaire (FOG) assesses severity unrelated to falls in patients with Parkinson's Disease (PD), FOG frequency, disturbances in gait, and relationship to clinical features conceptually associated with gait and motor aspects (e.g., turning). The FOG is comprised of 6 questions measured on a 0 to 4 scale (where 0 is normal and 4 represents severe abnormalities). The scores are summed together with 0 representing the best possible score and 24 representing the worst possible score.

The MDS-UPDRS part 1 focuses on non-motor symptoms, such as dementia, depression, and psychosis. The total summed score ranges from 0-52 with higher scores indicating increased non-motor impairment.

The MDS-UPDRS part 2 focuses on the patient's ability to perform daily motor activities including dressing, grooming, and using utensils. The total summed score ranges from 0-52 with higher scores indicating increased daily motor impairment

The MDS-UPDRS 4 focuses on Measures the complications of treatment, e.g. dyskinesias and motor fluctuations. The total summed score ranges from 0-24 with higher scores indicating increased motor complications.

The CPIB is a questionnaire that measures speech complications. The questionnaire is scored from 0 to 30, with a higher score indicating increased speech difficulties.

This questionnaire can be filled out by patients and assesses the impact that voice problems and limitations have on the individual's overall daily function. Questionnaire is scored from 0 to 40, with a higher score indicating increased speech difficulties.

Patients will be recorded while receiving vibrotactile stimulation. The Beta Band (13-30Hz) power spectral density (PSD) will be of interest. The units of the power spectral density are micro-Volts-squared per Hz. Increases in Beta band PSD are associated with motor impairment in Parkinson's disease, while decreases in the beta band are associated with motor improvement.

The PD-CFRS capture subjective daily functional cognitive decline among patients with Parkinson's disease over the past 2 weeks. The scale ranges from 0 to 24, with higher scores indicative of cognitive decline.

Participants will be assessed for their perceptive threshold of vibration, or the lowest vibration amplitude perceived. This is determined by adjusting the amplitude of the experimental device.