What is Atypical Parkinsonism?

Progressive Supranuclear Palsy (PSP)

Progressive Supranuclear Palsy (PSP) affects movement, vision, speech, and cognition, typically emerging in a person’s 60s. Most individuals survive 5-9 years post-diagnosis, though some live longer. Early signs include loss of balance and frequent falls, progressing to slow movements (bradykinesia), clumsiness, and trunk stiffness, often requiring wheelchair use over time.

A hallmark feature is abnormal eye movements, such as restricted vertical gaze, difficulty with eyelids, and a staring gaze, leading to blurred vision and light sensitivity. Speech becomes slow and slurred (dysarthria), swallowing difficult (dysphagia), and personality changes like apathy emerge, alongside cognitive challenges in attention and planning.

PSP affects 3-6 per 100,000 people worldwide (about 20,000 Americans), far rarer than Parkinson’s disease. First identified in 1964 as distinct from Parkinson’s, it’s sometimes called Steele-Richardson-Olszewski syndrome. No cure exists, but some symptoms may be managed with medication or therapy.

Quick Facts:

• No known cause or cure
• Affects balance, coordination, eye movement, speech, swallowing, and thinking
• Prevalence: 5-6 per 100,000
• Onset typically in early 60s, occasionally 40s
• Slightly more common in men, no racial or occupational preference

Symptoms:

• Loss of balance
• Personality changes
• Weak downward eye movements
• Weakened mouth, tongue, and throat movements
• Slurred speech
• Difficulty swallowing

Multiple System Atrophy (MSA)

Multiple System Atrophy (MSA) impacts movement and the autonomic nervous system, controlling blood pressure, digestion, and other involuntary functions. Its cause is unknown, but it involves alpha-synuclein protein clumps in glial cells, a focus of ongoing research to slow or stop the disease.

Symptoms:

• Slowness, stiffness, walking, and balance issues
• Clumsiness and incoordination
• Slurred speech
• Low blood pressure, constipation, bladder problems
• Inappropriate laughing or crying
• Acting out dreams (REM sleep behavior disorder)
• Breathing difficulties, especially at night

Corticobasal Degeneration (CBD)

Corticobasal Degeneration (CBD) affects movement, cognition, and behavior, often starting in one limb before spreading. It’s caused by tau protein buildup in brain cells, though the exact mechanism is unclear and under investigation.

Symptoms:

• Slowness and stiffness
• Dystonia (abnormal postures)
• Myoclonus (rapid jerks)
• Difficulty concentrating or cognitive changes
• Language issues (trouble finding words)
• Behavioral changes (e.g., crude actions)

When affecting an arm, CBD may cause "alien limb syndrome," where the limb moves involuntarily despite retained strength, complicating tasks like combing hair or unlocking doors. Walking and balance issues may develop later.