Multiple sclerosis (MS) is a chronic, inflammatory condition that affects the central nervous system, including the brain, spinal cord, and optic nerve. The National Multiple Sclerosis Society estimates that there are approximately 400,000 people living with MS in the United States. The condition occurs when the covering around the nerve, referred to as the myelin sheath, starts to break down making it difficult for electrical impulses to travel to and from the brain. A simplification of this process is to use the analogy of a hard-wired telephone system. Between the two people speaking to each other on a telephone is a line that transmits electrical impulses in the form of sound (i.e., voice). If the cover around the wiring is frayed or damaged in any way, the electrical impulse is muffled, distorted, or sometimes (when the damage is extensive enough) completely blocked. When the covering around the nerve starts to fray, the ability to transmit messages to and from the brain is either distorted or blocked (referred to as demyelination).

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