ASSESSING COGNITION IN ALZHEIMER-DISEASE RESEARCH

Because cognitive impairment is the central, defining symptom of Alzhe imer disease, cognitive assessments commonly are used as primary or se condary measures of outcome in Alzheimer disease research. The authors review the cognitive functions that decline in this neurodegenerative disease and summarize the necessary features of appropriate cognitive performance tests. The characteristics, strengths, and weaknesses of the major cognitive batteries employed as outcome measures in Alzheime r disease research are reviewed. Finally, the recent contributions to the development of cognitive measures by the Alzheimer's Disease Coope rative Study are presented briefly, followed by discussion of some cri tical issues for future test development.