APP and memory impairment: The Aβ depositions in the OB of APP/PS1 mice at 3–4 months of age precedes previous reports of Aβ in the entorhinal cortex and hippocampus, which are involved in learning and memory (Wu et al., 2013; Vasavada et al., 2015; Misiak et al., 2017), and this finding might explain why the 3–4-mo mice suffered olfactory deficits but did not experience memory impairments.