Multiple sclerosis (MS) is a chronic demelinating disease of the central
nervous system. Myelin is a fatty material that insulates nerves, acting
much like the covering of an electric wire and allowing the nerve to
transmit its impulses rapidly. It is the speed and efficiency with which
these impulses are conducted that permits smooth, rapid and co-ordinated
movements to be performed with little conscious effort. In MS, the loss
of myelin (demyelination) is accompanied by a disruption in the ability
of the nerves to conduct electrical impulses to and from the brain and
this produces various symptoms. The sites where myelin is lost (plaques
or lesions) appear as hardened (scar) areas: in MS these scars appear
at different times and in different areas of the brain and spinal cord
- the term multiple sclerosis meaning, literally, many scars. In almost
all lesions, a variable but usually substantial axonal loss occurs additionally
to the loss of myelin. Axonal loss is an important factor in MS because,
unlike demyelination, symptoms will not be affected by efforts to improve
conduction (Herndon in Burks & Johnson, 2000).
NOTES
The information contained in this page are taken from the Multiple Sclerosis
International Federation web site: www.msif.org
Sponsored by:
THE EUROPEAN COMMISSION
DG INFORMATION SOCIETY
UNIT B1-APPLICATION RELATING TO HEALTH