Multiple sclerosis (MS) isn't fully understood, but many believe it's an autoimmune disease that affects the central nervous system, or CNS. The CNS includes the brain, the spinal cord, and the optic nerves, and it's surrounded by a fatty tissue called myelin that protects the nerve fibers and helps them conduct electrical impulses.

What does MS do?

When a person has MS, he or she loses myelin in more than one, or multiple, areas. The resulting scar tissue is called sclerosis. Sometimes the nerve fiber itself is damaged or broken. When myelin is destroyed or damaged, the nerves can't conduct electrical impulses to and from the brain as well. This breakdown is what produces the symptoms of MS.

Symptoms of MS

The symptoms of MS are unpredictable and various. Here are a few of the more common ones.

• Fatigue
• Difficulty in walking
• Vision problems
• Emotional changes
• Problems with memory, attention, and problem-solving
• Bladder/bowel dysfunction
• Dizziness and vertigo
• Numbness/pain
• Sexual dysfunction

Varied Types of MS

Just as symptoms are different among individuals, so are the types of multiple sclerosis. Each of these types can be mild, moderate, or severe.

There are four recognized types of multiple sclerosis, ranging from those that cause periodic relapses or attacks of symptoms that subsequently 'remit' or go away to types that progressively worsen over time. These types further demonstrate why MS is such an unpredictable disease that affects those living with it in very different ways.

Facts About MS

• Every hour, someone is newly diagnosed with MS.
• More than 2.5 million people worldwide live with this unpredictable disease.
• MS is the most common neurological disease leading to disability in young adults.

Find out more about MS.