The objective is to design, build, and clinically assess ParkinStim", a home-based, noninvasive brain polarization system used during sleep to treat Parkinson's disease (PD). While current therapeutic standards of drug intervention and deep brain stimulation (DBS) show effective treatment of PD symptoms, transcranial direct current stimulation (tDCS) is a less expensive and less invasive potential alternative/adjunct treatment with few side effects that may help treat PD symptoms, decrease medication usage, and reduce sleep disturbances. Recent studies have demonstrated that noninvasive anodal tDCS applied to the scalp over primary motor cortex (M1) can improve PD symptoms. tDCS provides polarization to the cerebral cortex via painless weak currents transmitted through noninvasive scalp electrodes. Unlike other noninvasive stimulation modalities such as transcranial electrical stimulation (TES) and rapid transcranial magnetic stimulation (rTMS) that can be painful and cause side effects including seizures and psychotic symptoms, tDCS is painless, poses few side effects, and is ideal for home use since it can be provided in an inexpensive and compact package. The primary innovations of ParkinStim include 1) easy-to-don wearable tDCS hardware suitable for home use, 2) a technique for providing tDCS during sleep, and 3) a therapeutic tDCS system to treat PD symptoms and related sleep disturbances. The proposed system will provide a wearable device that patients with PD can easily don before going to sleep and use through the night. Since patients often feel worst in the morning after medication from the previous day has worn off, stimulation during the night may help patients wake up feeling better. Additionally, designing the device for overnight use will make the system convenient and accessible so patients need not worry about using the device in public or during their daily activities. Development will focus on treating the motor symptoms of PD;however, the proposed system may prove beneficial for other PD symptoms or related sleep disturbances. For this Phase I, we aim to demonstrate 1) technical feasibility by safely and effectively using existing stimulation and electrode hardware to provide tDCS to PD patients during sleep and 2) clinical feasibility by demonstrating that tDCS reduces PD symptom severities and decreases symptom fluctuations. Ten PD subjects will participate in a counterbalanced crossover clinical study during which tDCS is applied to M1 while the subject sleeps in a sleep laboratory and standard polysomnography data is collected. Phase I success criteria include safely and effectively administering tDCS to PD patients during sleep without causing waking and demonstrating an acute therapeutic effect of tDCS. While Phase I is designed to evaluate the acute benefits of tDCS, Phase II will investigate the chronic benefits of multiple nights of tDCS used in the home over several weeks. We hypothesize that the final system resulting from Phase I and II development will provide safe and effective tDCS during sleep, decrease PD symptom severities, minimize motor fluctuations, reduce required medication, and improve sleep quality.
Parkinson's disease affects nearly 1.5 million Americans with annual treatment costs approaching $25 billion. While current therapeutic standards of drug intervention and deep brain stimulation (DBS) show effective treatment of PD symptoms, transcranial direct current stimulation (tDCS) during sleep is a less expensive and less invasive potential alternative/adjunct treatment with few side effects that may help treat PD symptoms, decrease medication usage, and reduce sleep disturbances. Successful development will result in a safe, easy-to-use home-based tDCS therapy system PD patients can use during the night to feel better during the day.