Fig. 1.

Relationship between the development of tau pathology and Aβ deposition. a Tau pathology in the entorhinal cortex and hippocampus (ECH) belongs to the AD continuum. It is complemented over time by Aβ deposition that occurs in an ordered manner (no attempt has been made to represent the duration of each stage or phase; only the sequence is important here). b Panel b illustrates the PART hypothesis and the issues it raises. Tau pathology in the ECH differs from tau pathology in AD, with three major problems indicated by the dotted lines. 1 Can Aβ deposition precede tau pathology? 2 Can tau pathology related to PART occur with Aβ deposition phases 1–2? 3 How and where does PART end? Panel a describes our position