Early changes in visuospatial episodic memory can help distinguish primary age-related tauopathy from Alzheimer's disease.

The observation of neurofibrillary tangles (NFTs) without associated amyloid-beta (Aβ) in the brains of cognitively normal and cognitively impaired elderly individuals has, for many years, been a source of discussion and controversy. The term "primary age-related tauopathy" (PART) was introduced in 2014 and consensus guidelines for the condition were published [1]. The clinical manifestations of PART have been described (see [2] for review). A recent molecular imaging study suggested that mesial temporal tau load is associated with a decline in cognitive performance in those with no Aβ pathology [3].