Compared to participants with AD, the Aβ[ +] RHI/TBI group had a much lower cortical Aβ burden (mean CLs = 24 vs. 91) and the subset of Aβ[ +] RHI/TBI participants with tau PET also had a lower disease burden than the group with AD (mean metatemporal SUVR = 1.56 vs. 2.01). Here, MAPT is linked to Alzheimer disease.