APP and Alzheimer disease: Though many APP transgenic mouse models have been shown to develop relevant AD-related Aβ pathology and exhibit cognitive impairment within 6 to 12 months of age [2-4], the attempts to find specific correlations between molecular markers of Aβ processing and cognitive deficits in these mice, which express high levels of APP, creates challenges in deciphering the basis for cognitive changes that may occur in a model.