Neurochemical studies of Alzheimer''s disease

Age differences in the representation of semantic information may underlie the cognitive decline observed in aging. The objective of the present study was to determine to what extent elderly and young subjects agreed in the representations of semantic categories. Ninety elderly (77 women, 13 men) and 90 young (74 women, 16 men) participants wrote down the first four associations evoked by each of 30 semantic category names. Results showed differences between the two groups in items selected as most common responses (MCRs); frequency of occurrence of the MCRs differed between the two groups in 21 semantic categories. Results suggest that young and elderly subjects hold different representations of semantic categories and also highlight the importance of using age-appropriate norms in the evaluation of cognitive functions in aging.