Demyelinating plaque

Many nerves in the brain and spine are coated in myelin. Myelin is an insulating material which allows nerve signals to travel 100 times faster than they would without the myelin. When the myelin around the nerves are damaged, these nerve signals are slowed. This damage is called demyelination. A demyelinating plaque is a localized region of demyelination. New myelin can grow in areas of damage, but the new myelin is thinner and not as effective.