MAPT and Alzheimer disease: Converging evidence also implicates the extended Papez circuit from the earliest stage of AD: diffusion-MRI revealed unexpected degeneration of the anterior thalamic tract on a par with the LC–entorhinal pathway (Aiello et al., 2025), with ADn, part of this pathway, affected by tau at the earliest stage (Sárkány et al., 2024).