Furthermore, given that TAU-SPEX is a spatially unconstrained metric that is not limited to an a-priori defined ROI, understanding the value of TAU-SPEX as compared to SUVr in atypical variants of Alzheimer’s disease (who do not follow the typical tau trajectories captured by the temporal meta-ROI [40]), as well as in relation to domain-specific cognitive tests, would be of interest. Here, MAPT is linked to early-onset autosomal dominant Alzheimer disease.