In multiple sclerosis, damage to the myelin in the central nervous system and to the nerve fibers themselves interferes with the transmission of nerve signals between the brain and spinal cord and other parts of the body. This disruption of nerve signals produces the primary symptoms of MS, which vary depending on where the damage has occurred.
Over the course of the disease, some symptoms will come and go, while others may be more lasting. The severity of symptoms varies from person to person and may also fluctuate over the course of a day or week for any one individual.