“…This is a function which has been termed ‘pattern separation’, and has been established at a single-cell level in the rodent hippocampus (Gilbert et al, 2001; Leutgeb et al, 2007; Leutgeb et al, 2004) and neuroimaging in humans (Baker et al, 2016; Bakker et al, 2008; Berron et al, 2016; McHugh et al, 2007). An emerging view is that pattern separation is a key function altered in Alzheimer’s disease (AD) (Ally et al, 2013; Parizkova et al, 2020; Wesnes et al, 2014), while AD has analogously been linked with social isolation (Marioni et al, 2015; Penninkilampi et al, 2018; Shen et al, 2021; Xiang et al, 2021). For example, in a mouse model of AD, the investigators reported reduced Aβ synaptotoxicity in the hippocampus (Li et al, 2013), and reduced cognitive impairment (Jankowsky et al, 2005) with environmental enrichment ⍰ an important source of which in humans is regular social contact.…”