MAPT and supranuclear palsy, progressive, 1: PSP is a neurocognitive disorder, pathologically associated with accumulation of hyperphosphorylated 4-repeat tau, initially within the brainstem and basal ganglia before spreading to the cortex67; clinically it typically manifests with a movement disorder including axial rigidity, supranuclear gaze palsy and postural instability, with a dysexecutive, disinhibited and apathetic cognitive profile.115