More common in women and in cooler climates. One third have mild disorders, one third worsen gradually and one third worsen rapidly. Causes Underlying cause unknown. Patches of white matter in the spinal cord and brain degenerate and break down, and cannot conduct impulses. Genetic and viral causes suspected.
Recent studies suggest an auto-immune cause.
Signs and Symptoms Characterised by remissions and exacerbations. Weakness, difficulty with walking or balance. Vague loss of sensation or numbness and tingling. Apathy, lack of judgement or inattention. Marked sensory loss.