Computerized neuropsychological tests in the early detection of dementia: prospective findings.

This longitudinal study examines the sensitivity of 2 computerized neuropsychological tests, delayed matching to sample and paired associate learning, to early dementia of the Alzheimer type (DAT). Normal controls, patients in the early stages of DAT, and individuals with questionable dementia (QD) were studied. At 6 and 12 months after initial presentation, almost half of the QD group exhibited lower scores on the computerized subtests, maintaining their scores on standard testing. Over the same period NC subjects maintained their performance levels, while DAT patients continued to deteriorate. Linear discriminant function analyses of the computerized subtests at 6 and 12 months correctly classified 100% of the early DAT patients. Eighty-four and 79 percent of normal controls were correctly classified at 6 and 12 months respectively. Further development of these subtests for the detection of early dementia and the documentation of ongoing change in DAT is warranted. The findings are discussed in terms of the special sensitivity of these tests to the neuropathology of Alzheimer's Disease.