MAPT and Alzheimer disease: The tau‐PET signal does not consistently increase over time in cognitively normal individuals with Aβ‐negative (+), whereas deposition of tau in the cortexes increases by 0.5–3.0% annually in cognitively normal persons who are Aβ (+), and by 3.0–8.0% in Aβ‐positive patients with clinical AD.25, 26