It is also not clear that the temporal appearance of plaque pathology and cognitive deficits in the mouse models mirrors that of the human disease. Indeed, many of the mouse models exhibit behavioral deficits before significant plaque pathology.10 By contrast, substantial plaque pathology is probably present for some period of time before cognitive symptoms first appear in human AD.52 Interpretations of behavioral studies in the mouse are also complicated by the fact that it is difficult to know how precisely the behavioral tests used in mice model the cognitive deficits in humans.
