Acquiring a mnemonic: Age and category knowledge effects

Abstract

Fourth- and seventh-grade children received four free-recall trials on lists comprising typical and atypical items derived either from their own typicality ratings (self-generated lists) or the ratings of adults (adult generated). Levels of recall and clustering increased with age, were greater for typical than atypical items, with list effects (self- vs adult generated) being limited to atypical items. Subjects were classified as using an organizational strategy, separately for the typical and atypical items, based on the combined criteria of (a) at least one long intracategory cluster, and (b) faster within-category than between-category interitem latencies. The percentage of subjects classified as strategic was greater for the older children and typical items and increased over trials. By Trial 4, all seventh-graders were classified as strategic for either typical or atypical items, with 74% of fourth-graders so classified. Further analyses indicated that strategies were limited to a few categories on the early trials for both age groups, but generalized to most list categories on the later trials for the seventh-graders only. The results were interpreted in terms of the role that knowledge base and age differences in processing efficiency play in the development of memory strategies.