Progressive supranuclear palsy (PSP) is a neurodegenerative disorder characterized by pyramidal, extrapyramidal, and cerebellar symptoms with a characteristic abnormality of eye movements.

In 1961, Dr J. Clifford Richardson, Head of Neurology Division at Toronto General Hospital investigated and described eight middle aged patients presenting with supranuclear ophthalmoplegia (downward gaze), pseudobulbar palsy, dysarthria, dystonic rigidity of neck and upper trunk (nuchal dystonia) and dementia. Later he presented a clinical report of this “Heterogenous system degeneration” at the American Neurological Association (ANA) meeting in June 1963. Despite the presence of eminent neurologist none of them, except Dr. McNaughton of Montreal knew of similar cases. The histo-pathological reports of these cases, earlier described by Dr Olszewski, Dr. Steele and Dr. Richardson at the American Association of Neuropathology meeting, bore a striking resemblance to those seen in postencephalitic parkinsonism and in the parkinsonism–dementia complex of Guam (PDC), but differed in the distribution and intensity of neurofibrillary degeneration.

In 1964, the trio published their report of nine patients, in the Archives of Neurology suggesting a degenerative process or a chronic and late viral infection and referred to the condition as “Heterogeneous system degeneration”. But since Richardson was not certain of the disease etiopathogenesis, he suggested it be called progressive supranuclear palsy (PSP), later also known as “Steele-Richardson-Olszewski Syndrome”.

This syndrome is now considered to be due to taupathy with characteristic ‘hummingbird sign’ abnormality seen in midbrain on MRI. Despite great advancement in the imaging of brain and neuropharmacology of the PSP, the very detailed clinical and histo-pathological observations made by the trio of Dr. Steele, Richardson and Olzsweski deserve an important place in the history of Neurology.