A term used to describe a condition that becomes more severe and/or extensive over time.
(Steele–Richardson–Olszewski syndrome) a progressive neurological disorder resulting from degeneration of the motor neurons, basal ganglia, and brainstem. Starting in late middle age, it is characterized by a staring facial expression due to impaired ability to move the eyes up and down, progressing to difficulties in swallowing, speech, balance, and movement and general spasticity. The condition enters the differential diagnosis of *parkinsonism, with which it is often confused in its early stages.... progressive supranuclear palsy
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