APP and early-onset autosomal dominant Alzheimer disease: Increased brain activity is observed very early in Alzheimer’s patients [for an example see (Dickerson et al., 2005)] and increased neuronal excitability is also observed in a rodent model of Alzheimer’s disease (APdE9 mice carrying the APP Swedish mutation and a deletion of exon 9 of PSEN1) compared to wild-type rodents and is linked with the accumulation of amyloid-β and an enhanced susceptibility of seizure and epileptiform activities (Minkeviciene et al., 2009).