A lowering in basal forebrain cholinergic ChAT-IR neurons would therefore contribute to an explanation of the behavioural age-dependent deficits in episodic-like memory previously observed in L1 (Melis et al., 2015) and is at the same time reminiscent of the pathology and cognitive decline typically at play in Alzheimer’s disease (Grothe et al., 2010; Pedroso et al., 2018). This evidence concerns the gene CHAT and Alzheimer disease.