Remembering and knowing in adulthood:: Effects of enacted encoding and relations to processing speed

We examined age differences in recollective experience accompanying recognition using Tulving's (1985) remember/know procedure, in a population-based sample of adults ranging in age from 35 to 90 years (N=323). A guided encoding condition (enactment) was compared with a non-guided encoding condition. The relation between age differences in remembering and measures of processing speed was furthermore examined. The results demonstrated higher levels of remembering following enacted encoding, but age-related decrease in remember reports following both non-guided and guided encoding. The frequency of know-reports exhibited an age-related decrease, but this effect was weak. Importantly, a large amount of the explained variance in remembering was shared by age and processing speed. Together, these results are more consistent with a common cause or processing deficiency interpretation, than with a production deficiency interpretation of age differences in recollective experience.