High Frequency Light, Sound, and Tactile Stimulation to Improve Motor and Cognitive Deficits in Parkinson's Disease

Parkinson's disease (PD) impacts different types of neural oscillations in the brain, including beta (13-30Hz) and gamma oscillations (30-80Hz), which contributes to PD's cardinal symptoms of resting tremor, rigidity, bradykinesia (slowness of movement), and gait instability. The investigators' lab has developed a non-invasive method of increasing gamma power in the brain using Gamma Entrainment Using Sensory Stimulation (GENUS) through light, sound, and tactile stimulation devices. For this study, 40 participants with mild Parkinson's disease will be recruited, and the investigators will assess their brain waves with electroencephalogram (EEG) before, during, and after light, sound, and tactile stimulation to determine the safety, feasibility, and optimization of GENUS as a potential therapy in the PD population.

It is known that Parkinson's disease (PD) patients have disruptions in brain waves, specifically the beta frequency (13 - 30Hz) and gamma frequency (\~30 - 100 Hz), due to the death of dopaminergic neurons in certain parts of the brain. These disruptions of brain rhythms contribute to the cardinal symptoms of Parkinson's (resting tremor, rigidity, bradykinesia or slowness of movement and gait stability) in different ways. The investigators' lab has developed a non-invasive method of neuromodulation called Gamma Entrainment Using Sensory Stimulation (GENUS), which could be used for patients suffering from motor symptoms due to PD. GENUS is administered via light, sound, and tactile stimulation devices which emit light, audio, and tactile frequencies respectively. GENUS has been tested on cognitively normal individuals and individuals with mild Alzheimer's Disease (AD), and the device was found to be safe for use and effective for entrainment in both populations. Investigators hypothesize that boosting gamma oscillations using 40Hz GENUS will augment movement and improve tremor and bradykinesia in PD patients. Thus, the purpose of this study is to determine whether gamma entrainment through non-invasive 40Hz sensory stimulation can be observed in patients with PD as measured by electroencephalogram (EEG) during an acute stimulation session. Investigators also hope to determine whether the GENUS devices are safe and easy to use in the PD population. The investigators will recruit 40 participants diagnosed with mild PD who will be randomly assigned to two study arms: control stimulation and active 40Hz stimulation. Participants will be asked to do a series of movement exercises while wearing an actigraphy watch that tracks their activity before the stimulation session. Cognitive and mental health evaluations and memory tests will also be performed on all participants before and after exposure to the GENUS devices, which can deliver light, sound, and tactile waves at different frequencies. The first GENUS device is composed of a panel with light-emitting diode (LED) illumination and speakers for auditory stimulation, whilst the second device is composed of a small vibrating speaker for tactile stimulation. Each of the two groups will have different combinations of light, sound, and tactile settings.