Adult age differences in source recall: a population-based study.

Age differences in source recall were investigated in a population-based sample of healthy adults aged 35 to 80 years (N = 1000). Participants, who were screened on a variety of demographic, psychological, and biological variables, studied facts about well-known and unknown persons that were presented in four different ways, depicting four different sources of item information. An age-related deterioration of both item and source recall was observed, with source recall being more impaired than item recall. Source error analyses revealed an increase of source amnesia in subjects aged 75-80 years. Individual differences in background variables, age, gender, and word comprehension were related to source recall of well-known items, whereas age and years of formal education were related to source recall of unknown items. Source amnesia was accentuated in the two oldest cohorts and related to word comprehension. The age-related tendency to forget the source even when the fact is retained is suggested to be a specific feature of cognitive aging.