Symptoms & Causes of PSPS
What Are the Symptoms?
Symptoms vary from individual to individual and will change as the disease progresses. Typically, PSPS begins with balance problems. Other warning signs include:
- Slow and unstable gait
- Stiff muscles in the neck and back
- A tendency to fall backward
- Difficulty blinking and opening eyes
As the PSPS progresses, individuals often develop changes in speech and swallowing, including by not limited to:
- Speech becomes slurred, soft, and hoarse.
- Difficulty swallowing food and liquid may result in drooling, weight loss, and pneumonia.
- Speech apraxia can occur, meaning the coordination of oral movements that produce syllables, words, and phrases becomes impaired. In speech apraxia, speech sounds become distorted and erroneously generated.
Cognitive (thinking) changes in PSPS include impaired attention, organization, multi-tasking, and planning.
Behaviorally, individuals with PSPS can become impulsive or apathetic. As is commonly seen in behavioral variant frontotemporal (bvFTD) dementia, those with PSPS can variably demonstrate changes in diet, ritualistic behaviors, and loss of empathy.
PSPS is sometimes referred to as a Parkinson’s-plus syndrome, meaning that it is a disease that shares some of the symptoms of Parkinson’s disease.
What Causes PSPS?
PSPS can be caused by a number of neurodegenerative diseases. The absolute diagnosis of these is made on the basis of a brain autopsy performed by a neuropathologist. These diseases include progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). In CBD and PSP, there is an abnormal build-up of a protein called tau in the brain. These protein deposits destroy healthy brain cells and, depending on their location in the brain, give rise to the motor, cognitive, and behavioral symptoms of PSPS.
Most cases of PSP are sporadic, which means there is no one specific genetic mutation causing the disease. In sporadic PSP, genetic and environmental risk factors play a role but do not directly cause disease.
In the exceedingly rare genetic form of PSP, disease is transmitted from one generation to the next by a mutation in the MAPT gene, which provide the brain with the instructions for making the protein called tau. Individuals with this form of PSP come from families in which as many as half of the members are affected.