Associative learning and short-term forgetting as a function of age, perceptual speed, and central executive functioning.

In a study of two components of associative learning, it was found that during acquisition older people were more likely to forget material on which they were previously correct, but only for associations which were not well learned. Older people also formed fewer correct associations in the course of the task. Differences in learners' perceptual speed were found to account for some of the age deficit in the number of learning attempts, but speed was less relevant in accounting for age differences in forgetting and in the ability to generate new responses. Measured central executive functioning was less important in accounting for age differences on all measures. It is argued that forgetting is less important as a source of learning performance than has been suggested elsewhere (e.g., Salthouse, 1994). Rather, it is the inability of older persons to form associations as rapidly as younger ones which accounts for most of the age effect.