- Sclerosis, multiple (MS)
- The National Multiple Sclerosis Society says of MS that it is "a disease that randomly attacks your central nervous system, wearing away the control you have over your body. Symptoms may range from numbness to paralysis and blindness. The progress, severity and specific symptoms cannot be foreseen. You never know when attacks will occur, how long they will last, or how severe they will be. Most people are diagnosed with MS between the ages of 20 and 40...." In medical terms, MS involves demyelinization of the white matter sometimes extending into the gray matter. Demyelinization is loss of myelin, the coating of nerve fibers composed of lipids (fats) and protein that serves as insulation and permits efficient nerve fiber conduction. The "white matter" is the part of the brain which contains myelinated nerve fibers and appears white, whereas the gray matter is the cortex of the brain which contains nerve cell bodies and appears gray. When myelin is damaged in MS, nerve fiber conduction is faulty or absent. Impaired bodily functions or altered sensations associated with those demyelinated nerve fibers give rise to the symptoms of MS. Recent research (1998) has also identified nerve cell death as part of the nervous system injury in MS.