MAPT and Alzheimer disease: In addition, both amyloid and tau generated animal models of AD exhibit neurodegeneration in olfactory regions and olfactory deficits (Cassano et al., 2011; Wesson et al., 2011; Saiz-Sanchez et al., 2012; Gandy et al., 2013; Kong et al., 2018; Adlimoghaddam et al., 2019; Ghosh et al., 2019).