Study participants will undergo fourteen weeks of on-label PoNS therapy and, specifically, two weeks in-clinic PoNS therapy directly supervised by a physical therapist who has been trained on PoNS therapy by Helius Medical and certified as a clinic PoNS trainer (Phase 1) followed by 12 weeks of at-home unsupervised PoNS therapy Once weekly in-clinic PoNS therapy session (Phase 2). Subjects will be then asked to return to the clinic six month after the end of the study Phase 2 to assess maintenance of PoNS therapy effects.