title: Primary aging, secondary aging, and intelligence.
abstract: The distinction between primary aging, representing innate maturational processes, and secondary aging, representing the effects of environment and disease (Busse, 1969), was used to develop a model for the assessment of factors that are associated with age-related individual differences in intelligence. Intelligence was measured by performance on a number of tests that measure cognitive abilities known to decline with age. In a hierarchical multiple regression analysis, primary aging and education but not health explained a significant portion of the variance in fluid intelligence. Chronological age had a residual effect over and above that of primary and secondary aging, indicating that there was remaining age-associated variance unaccounted for in the proposed model. The results suggest that the model of primary and secondary aging is a valid means of operationalizing chronological age.
authors.affiliation: Academic Department of Psychogeriatrics, Prince Henry Hospital, Little Bay, New South Wales, Australia.
authors.forename: K
authors.initials: K
authors.lastname: Anstey
authors.forename: L
authors.initials: L
authors.lastname: Stankov
authors.forename: S
authors.initials: S
authors.lastname: Lord
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000375:Aging; D001307:Auditory Perception; D003071:Cognition; D015350:Contrast Sensitivity; D004777:Environment; D005121:Extremities / Q000293:injuries*; D005260:Female; D006801:Humans; D007360:Intelligence; D008019:Life Style; D011434:Proprioception; D014796:Visual Perception