Multiple sclerosis (MS) is a condition that affects the brain and spinal cord
resulting in loss of muscle control, vision, balance, sensation (such as
numbness) or thinking ability.
According to the National Multiple Sclerosis Society, the condition affects
approximately 400,000 Americans and is, with the exception of trauma, the most
frequent cause of neurological disability beginning in early to middle
adulthood. MS is two to three times as common in females as in males and its
occurrence is unusual before adolescence.
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. In MS, the
immune system attacks the brain and spinal cord, the two components of the
central nervous system.
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 plaque forms 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 receive messages. It is this breakdown of communication that causes the
symptoms of MS.