Generality and specificity in cognitive aging: A volumetric brain analysis

Objective: To investigate whether, in old age, brain volume differences are associated with age-related change in general mental ability and/or specific cognitive abilities. Methods: The authors investigate the association between brain volumes and current cognitive function in a well-characterized sample of healthy old people (aged 79-80) whose intelligence was recorded at age 11. This allowed estimation of intellectual change over the life span. Results: After accounting for childhood intelligence, associations were found between specific cognitive measures and brain volumes. An association was also found between volumes and the general intelligence factor g. After removing the influence of g from each of the specific cognitive measures, no remaining significant associations were found between brain volumes and the specific part of each test. Conclusions: Generalized cognitive aging is associated with brain volume differences, but there is no evidence in this sample that specific components of cognitive aging are associated with differences in brain volume. (c) 2005 Elsevier Inc. All rights reserved.