This good, short description of PSP is on the Genetic and Environmental Risk Factors in PSP study website. (This is the NIH-funded study being conducted under the leadership of Dr. Irene Litvan at the University of Louisville.) I liked the term “intellectual losses” rather than dementia or cognitive impairments.
http://pspstudy.com/aboutpsp.html
Facts About Progressive Supranuclear Palsy and Related Disorders
* Progressive Supranuclear Palsy (PSP) is the most common atypical parkinsonian disorder.
* Approximately 20,000 Americans – or 5 in every 100,000 people over the age of 60 – have PSP, making it much less common than Parkinson’s disease, which affects more than 1,000,000 Americans, but more common than amyotrophic lateral sclerosis (Lou Gherig’s disease). Patients are usually middle- aged or elderly. Men are affected more often than women.
* Experts suspect that PSP is under-diagnosed, or misdiagnosed as having Parkinson’s disease as affected persons may dismiss symptoms as signs of aging.
* Symptoms of PSP are caused by a gradual deterioration of brain cells in a few, tiny, but important places at the base of the brain called the brainstem. One of these areas, the substantia nigra, is also affected in Parkinson’s disease. Damage to this region of the brain accounts for the motor symptoms that PSP and Parkinson’s have in common. However, involvement of other motor nuclei in PSP explain these patients’ limited or lack of benefit from dopaminergic therapy.
* Abnormal deposits of the protein Tau, which are also found in Alzheimer’s disease, are characteristic of PSP, suggesting a possible link between these two neurodegenerative diseases.
* Symptoms may vary greatly from person to person, but commonly include:
o Loss of balance while walking. At times, the falls are described by the person experiencing them as dizziness attacks, prompting suspicion of an inner ear problem.
o Paralysis (“palsy”) of eye movements, especially in the downward direction.
o Emotional or personality changes such as apathy and irritability.
o Slurred speech and intellectual losses such as difficulty recalling events, mental slowing, and difficulty with abstract reasoning.
* PSP is often misdiagnosed as Parkinson’s disease because of the general slowing of movement. Less often, it is mistaken for Alzheimer’s disease or frontal dementia, because of changes in intellect and personality.
* Scientists do not know what causes PSP. There is no evidence that PSP is contagious. Genetic factors alone have not been implicated in most patients. Current scientific theories suggest a combination of environmental, occupational or other genetic risk factors.