NPAS4 and memory impairment: Though deletion of Npas4 is not lethal, mice lacking the Npas4 gene display numerous deleterious phenotypes that negatively impact upon the animal’s fitness including a shortened lifespan (Ooe et al., 2009), vulnerability to seizure (Lin et al., 2008), memory impairments (Ramamoorthi et al., 2011; Coutellier et al., 2012) and sensorimotor deficits (Coutellier et al., 2012).