Causes

The cause of progressive supranuclear palsy isn't known. The signs and symptoms of the disorder result from deterioration of cells in areas of your brain, especially those that help you control body movements and thinking.

Researchers have found that the deteriorating brain cells of people with progressive supranuclear palsy have abnormal amounts of a protein called tau. Clumps of tau are also found in other neurodegenerative disorders, such as Alzheimer's disease.

Rarely, progressive supranuclear palsy occurs within a family. But a genetic link isn't clear, and most people with progressive supranuclear palsy haven't inherited the disorder.