AGE-RELATED COGNITIVE DECLINE AND ELECTROENCEPHALOGRAM SLOWING IN DOWNS-SYNDROME AS A MODEL OF ALZHEIMERS-DISEASE

We studied quantitative electroencephalogram and neuropsychological performance in an aging series of 31 patients with Down's syndrome and compared the findings with those of 36 patients with probable Alzheimer's disease and age-matched controls. We found an age-related decline of cortical functions and slowing of the electroencephalogram in Down's syndrome patients aged from 20 to 60 years. Slowing of the electroencephalogram, i.e. the decrease of the peak frequency, was significantly related to Mini-Mental status scores, and visual, praxic and speech functions, as well as memory in the Down patients, similar to the Alzheimer patients. Similar correlations were not demonstrated for young or elderly controls. This study provides neuropsychological and electrophysiological data to suggest that studying Down's syndrome patients of different ages can serve as a model for progression of Alzheimer's disease.