Separation of tau-positive lesions into progressive supranuclear palsy (PSP) and Alzheimer disease (AD) based on their distribution and cytopathology. Tau-positive lesions of PSP shown in green (left column, a-e), typically include primary motor cortex (PC), putamen (PU), globus pallidus (GP), subthalamic nucleus (STN), central grey matter (CGM), substantia nigra (SN), red nucleus (RN), tegmentum (M-TEG), locus coeruleus (LC), pontine nucleus (PN) and tegmentum (P-TEG), inferior olivary nucleus (ION) and dentate nucleus (DN) in the cerebellum. Tau-positive lesions of Alzheimer disease (AD), shown in grey (right column A-C), are more restricted to CGM, SN and LC in the brainstem while more extended in the hippocampal formation (HF) and cerebral cortex (CC). In the five comorbid cases with PSP and AD (PSP + AD in the mid column), these tau-positive lesions are partly overlapping. Regions with neurofibrillary tangles (NFTs) with tuft-shaped astrocytes (TAs) are labeled in italics, which replicate of PSP-type distribution (left column). Those with NFTs without TAs are labeled in Bold face (HF, LC and PN), which replicate AD-type distribution. Cerebral left hemisphere (coronal), b: Midbrain (axial), c: Pons (axial), d: Medulla oblongata (axial), e: Cerebellum.