CSF levels of TNF-α, produced by brain cells, areincreased in some AD patients (Tarkowski et al.,1999); TNF-α mediates LTP inhibition as well asmemory deficits caused by Aβ (Rowan et al., 2007;Tobinick, 2009; Wang et al., 2005).In aged APP/PS1 mice, a model of AD in which TNF-α levels aretwofold higher than in their WT counterparts, there is a markedTNF-α-dependent inhibition of LTP possibly due to elevated TNF-αproduction by Aβ-dependent glial cell activation (Singh etal., 2019). Here, APP is linked to Alzheimer disease.