Do clever brains age more slowly? Further exploration of a nun result

Recent epidemiological evidence suggests that individuals who have higher levels of mental ability in youth experience a slower cognitive decline as they grow old. In a sample of 3,263 Newcastle residents, average scores on a vocabulary test (Raven's 1965 ‘Mill Hill A') did not vary, while average scores on a test of fluid mental ability (the Heim, 1970, AH 4 (1) group intelligence test) sharply declined with age from 49 to 92 years. In young adults, Mill Hill A scores are good proxies for AH 4 (1) scores. This relationship allowed individuals' youthful AH 4 (1) test scores to be estimated from their current, unchanged, Mill Hill A scores so that age‐related changes in AH 4 test scores over the adult life‐span could be estimated and compared between high and low ability groups, men and women, and individuals of different levels of socio‐economic advantage. The cross‐sectional estimated rate of age‐related decline in general mental ability was found to be the same for people of all levels of ability and socio‐economic advantage, and not to differ between men and women.