Preservation of the attribute knowledge of concepts in normal aging groups

The aim of this study was to detect possible alterations in semantic representation during normal aging. Forty young subjects (aged 20 to 30 years) and 40 elderly ones (divided into two groups of 60 to 70 years and 70 to 80 years), all in good health and with high education, completed a test protocol used for assessing semantic knowledge in the study of Alzheimer's disease. The same list of 42 words belonging to three different semantic categories was presented visually three times to the subjects, each time with different instructions: (a) find the words with one letter N (or more) (training task); (b) find the names of animals (test of categorical knowledge); (c) find the words representing something that prick (test of attribute knowledge of concepts). A two-way analysis of variance showed an effect of task (the times taken were significantly longer for the attribute-knowledge test), a group effect (the elderly subjects were slower) and an absence of interaction (the elderly subjects had the same profile as the young group). The results indicate the preservation of the semantic memory in normally aging groups and the usefulness is emphasized in the context of the data given in the literature on Alzheimer's disease.