Although memory remains intact, the slowed speech and thought patterns and the rigid facial expression may be mistaken for senile dementia or Alzheimer's disease. Emotional responses may become exaggerated and inappropriate, and the patient may experience anxiety, depression, and agitation. The cause of PSP is not known. Most people who develop PSP come from families with no history of the disease, so it does not seem to be inherited, except in certain rare instances. People who have PSP seem to lack the neurotransmitters dopamine and homovanillic acid in the basal ganglia.
Neurotransmitters are chemicals that help carry electrical impulses along the nervous system.
Neurofibrillary tangles are also found in Alzheimer's disease, but the pattern is somewhat different. Diagnosis PSP is sometimes mistaken for Parkinson's disease, which is also associated with stiffness, frequent falls, slurred speech, difficulty swallowing, and decreased spontaneous movement. Treatment PSP cannot be cured. Drugs are sometimes given to relieve symptoms, but drug treatment is usually disappointing. As the disease progresses, the difficulty in swallowing may cause the patient to choke and get small amounts of food in the lungs.