Progressive Supranuclear Palsy (PSP) is caused by damage to certain neurons that results in progressive lack of coordination, stiffness in neck and trunk, slow movements, difficulty with eye movement, difficulty walking which may result in falls and cognitive dysfunctions. The disorder is found commonly in people above 60 years of age.
The disorder is also called as Steele- Richardson- Olszewsky syndrome.
The classical symptom of PSP involve a tendency to fall unexpectedly, usually backwards. Other common symptoms include rigidity and backward arching of the neck, and a key diagnostic feature, the Supranuclear Palsy. This is a difficulty in ‘willed’ upgaze and downgaze, ie. the ability of the patient to voluntarily move their eyes up and down while keeping the head still.
Since the symptoms of PSP are similar to Parkinson's disease, the disorder could be misdiagnosed as Parkinson's in its early stages.
Motor symptoms come first and always precede cognitive changes.
The cause of PSP is as yet unknown, though there may be a genetic, as well as an environmental, component. However, as observed in many neurodegenerative disorders, tau proteins or tau gene is likely a significant causal factor. Indeed, there is a genetic risk factor linked to H1H1 haplotype in the tau gene.