MAPT and Alzheimer disease: This group includes primary tauopathies, such as progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), Pick disease, frontotemporal dementia, and PART, as well as secondary tauopathies, including AD and chronic traumatic encephalopathy.[33] Despite their diversity, these diseases are likely interconnected through shared underlying mechanisms that influence their manifestation.[2a] Given tau pathology as a key common mechanism, tau has emerged as an attractive target for therapeutic development.