Multiple-Sclerosis Fact Sheet
Multiple sclerosis (MS) is an autoimmune disorder that affects the nervous system. When someone has MS, that person’s own immune system attacks its own nervous system, which causes periods of vision loss, numbness, pain and an array of other symptoms. Your nervous system consists of specialized cells called neurons, which transmit signals to and from your brain. You use neurons every time you move, walk, read, think, see, feel objects, etc. If something happens to any one of those groups of neurons, it will prevent you from doing everyday tasks you take for granted.
During an MS flare up, the immune system attacks a component of the nervous system called myelin, which is a special cover on the neurons that help them work properly. It works like insulating material on electric wire; without it, the neurons become unable to function.