Advances in the early detection of Alzheimer's disease.

The combination of an aging population and the promise, possibly in the near future, of disease-modifying therapies have made the characterization of the early stages of Alzheimer's disease (AD) a topic of major research interest. In this article we review recent progress in our understanding of the evolution of early AD with particular reference to the symptomatic pre-dementia stage designated 'mild cognitive impairment', emphasizing work on the early cognitive profile and associated neuroimaging studies.