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Fatal insomnia is a rare human prion disease charac-terised by sleep–wake disturbances, thalamic degenera-tion and deposition of type 2 disease-specific prion protein (PrPSc). This report details a patient with sporadic fatal insomnia who exhibited cerebral deposition of type 1 PrPSc and neuropathological changes largely in the basal ganglia. Previous damage of this brain region by a surgically removed colloid cyst and the insertion of two intracerebral shunts may have influenced the distribution of PrPSc through a chronic inflammatory process. These findings add to our knowledge of the phenotypic variability of human prion diseases with prominent sleep distur-bances. Prion diseases share the same pathogenic mechan