Progressive Supranuclear Palsy (PSP) is a neurodegenerative condition that arises in the 6th to 7th decade of life. The major symptoms are motor disturbances, including immobility of the facial musculature, vertical gaze palsy, dysarthria (difficulty speaking), and rigidity of the trunk and neck muscles. The course of the disease is progressive and can lead to mild to moderate frontal dementia. Neurodegenerative changes are widespread, involving various brainstem structures, the basal ganglia, and cerebellum, and finally spread to frontal cortex. The predominant neurodegenerative changes include neuronal loss and the development of globose tangles, although granulovacuolar degeneration has been described as well. Glial involvement in PSP is massive, and is readily demonstrated with tau antibodies. Pathological glial structures include thorny and tufted astrocytes, coiled bodies and glial threads. Tau-66-reactive microglia are also present.

Reference: Steele, et al., 1964