Modeling individual differences in working memory performance: a source activation account

Working memory resources are needed for processing and maintenance of infor mation during cognitive tasks. Many models have been developed to capture t he effects of limited working memory resources on performance. However, mos t of these models do not account for the finding that different individuals show different sensitivities to working memory demands, and none of the mo dels predicts individual subjects' patterns of performance. We propose a co mputational model that accounts for differences in working memory capacity in terms of a quantity called source activation, which is used to maintain goal-relevant information in an available state. We apply this model to cap ture the working memory effects of individual subjects at a fine level of d etail across two experiments. This, we argue, strengthens the interpretatio n of source activation as working memory capacity. (C) 2001 Cognitive Scien ce Society, Inc. All rights reserved.