Demyelination in the nerves that send messages to the muscles causes problems with movement (motor
symptoms), while demyelination along the nerves that carry sensory messages to the brain causes
disturbances in sensation.
Are Symptoms the Same in Every Person?
Multiple sclerosis follows a varied and unpredictable course. In many people, the disease starts with a
single symptom, followed by months or even years without any progression of symptoms. In others, the
symptoms become worse within weeks or months.
It is important to understand that although a wide range of symptoms can occur, a given individual may
experience only some of the symptoms and never have others. Some symptoms may occur once,
resolve, and never return. Because MS is such an individual disease, it is not helpful to compare yourself
with other people who have MS.
What Is Multiple Sclerosis?
Multiple sclerosis or MS is a disease that affects the brain and spinal cord resulting in loss of muscle
control, vision, balance, and sensation (such as numbness). With MS, the nerves of the brain and spinal
cord are damaged by one's own immune system. Thus, the condition is called an autoimmune disease.
Autoimmune diseases are those whereby the body's immune system, which normally targets and
destroys substances foreign to the body such as bacteria, mistakenly attacks normal tissues. In MS, the
immune system attacks the brain and spinal cord, the two components of the central nervous system.
Other autoimmune diseases include lupus and rheumatoid arthritis.
The central nervous system is made up of nerves that act as the body's messenger system. Each nerve
is covered by a fatty substance called myelin, which insulates the nerves and helps in the transmission of
nerve impulses, or messages, between the brain and other parts of the body. These messages control
muscle movements, such as walking and talking.
MS gets its name from the buildup of scar tissue (sclerosis) in the brain and/or spinal cord. The scar
tissue or plaques form when the protective and insulating myelin covering the nerves is destroyed, a
process called demyelination. Without the myelin, electrical signals transmitted throughout the brain and
spinal cord are disrupted or halted. The brain then becomes unable to send and to receive messages. It is
this breakdown of communication that causes the