These data, obtained from Tau KO mice (Fig. 3, Fig. 4), IL-6 KO (Fig. 5, Fig. 6) and CypD KO (Fig. 7, Fig. 8) mice, indicated the mitochondrial dysfunction in young mice was dependent on Tau and IL-6, but independent of synaptic loss and cognitive impairment, in young mice. This evidence concerns the gene IL6 and Cognitive impairment.