With the inherent difficulty of detecting significant improvements in cognitive performance in normal healthy subjects, it is presently incredibly hard to predict and select efficacious agents early in the drug development process. As such the potential success of novel therapeutic agents for the symptomatic relief of Alzheimer's disease (AD) is largely unknown until the drugs enter relatively large studies, assessing clinical outcome over at least a six month period. To try to overcome this issue, clinical scientists have focused their attention to the development of cognitive endpoints/biomarkers that can be detected in a number of experimental paradigms where cognitive impairments akin to those observed in AD, have been artificially induced.Based on the scientific literature, the use of total Sleep Deprivation in healthy volunteers seems to be a good paradigm to assess potential anti-AD agents.