The investigators hypothesis is that electrical stimulation to the tongue that directly stimulates two cranial nerve nuclei (Trigeminal and Facial Nerve Nuclei), will excite neural impulses to the brainstem and cerebellum. The investigators call this cranial nerve non-invasive neuromodulation (CN-NINM). The activation of these structures induces neuroplasticity when combined with specific physical exercises, can reduce symptoms of advanced MS, targeting primarily postural stability (sitting and standing), upper extremity movement, and ability to perform self-transfers.