CHAT and Alzheimer disease: Considering the crucial role of the cholinergic system on learning and memory (Maurer and Williams, 2017; Solari and Hangya, 2018), as well as its role in AD (Beach et al., 2000; Ramos-Rodriguez et al., 2013; Hampel et al., 2018), the number of ChAT+ producing neurons in the MS/DB were analyzed.