To investigate the differential susceptibility of hippocampal subregions to AD tau pathology, we used AT8 antibody to detect phosphorylated paired-helical-filament tau in the postmortem brains of AD patients, focusing on the anterior–posterior axis (which corresponds to the ventral-dorsal axis in rodents) of the hippocampus (Fig. 1a). Here, MAPT is linked to Alzheimer disease.