The recognition of the limits between normal and pathological ageing is essential for the adoption of evidence based health policies for people with 65 or more years old. This study is part of a systematic effort that the research group of the Laboratory of Investigations in Chronic Neurodegeneration and Infection at the Federal University of Pará has been doing to provide translational information on the normal and altered neurobiology of aging. The long term main goal is to enable evidence based public policies for health ageing in the Amazon Region. This report aims to investigate the effects of aging on the performances in selected neuropsychological tests to assess learning, memory and language impairments. 29 young adult (29.9 ± 1.06 years) and 31 older adults (74.1 ± 1.15 years) were selected and the results of their performances were compared using both parametric tests and multivariate statistical analysis. A general assessment and a variety of cognitive tests including Mini Mental State Examination (MMSE), selected visuo-spatial learning and memory tasks from the Cambridge Neuropsychological Test Automated Battery (CANTAB) and language tests (Phonological and Semantic Verbal Fluencies, Reduced Boston Naming, Narrative Performance on the Boston “cookies theft picture” description and in some of the Battery Montreal Evaluation of Communication - MAC tests. BioEstat version 5.0 and SPSS packages of ware were used for statistical analysis. Parametric Student's t test or nonparametric Mann-Whitney test were applied to detect significant differences (set at p values <0.05). Groups were matched for education and included both males and females. The analysis of subcategories that comprise the MMSE showed significant difference only in the word list memory recall, in which the elderly group showed worse performance compared to the young group. There were statistically significant differences between aged and young adults performances in the following language tests: 1) Reduced Boston Naming, 2) Narrative Performance on the Boston “cookies theft picture” description, 3) Metaphors; 4) Emotional and Linguistic Prosody. As compared to the young adults, aged subjects showed worse performances on ten different measurements of visuo-spatial CANTAB memory and learning tests. Euclidean distances and discriminant analysis from cluster analysis applied to CANTAB and language results demonstrated that CANTAB tests distinguished the groups with higher resolution. The effects of aging o neuropsychological tests results revealed that the visual memory selected tests from CANTAB battery, are more sensitive and better discriminates subgroups in both young adults and aged voluntaries. We concluded that the large-scale application of CANTAB selected tests, both in longitudinal and in cross-sectional studies, will increase our ability to distinguish the limits between normal and pathological aging.
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