MAPT and Mental deterioration: Using transgenic (Tg) mice exhibiting tau-induced cognitive decline, a number of studies have indicated that loss of dendritic spine or depletion of synaptic proteins appear prior to hallmark pathologies (Eckermann et al., 2007; Yoshiyama et al., 2007; Mocanu et al., 2008; Polydoro et al., 2009; Bittner et al., 2010; Hoover et al., 2010; Rocher et al., 2010; Crimins et al., 2011; Sydow et al., 2011a,b; Alldred et al., 2012; Spires-Jones and Knafo, 2012; Kopeikina et al., 2013).