INDIVIDUAL AND AGE-RELATED DIFFERENCES IN CHILDRENS WORKING-MEMORY

The purpose of this study was to investigate the degree to which age-r elated and individual differences in children's working memory (WM) ar e due to a general or task-specific capacity system. Experiment 1 corr elated children's (N = 146; age range 5-19 years) verbal and visual-sp atial working memory performance with various intelligence and achieve ment measures. The results supporting a general system were that (1) v isual-spatial and verbal WM measures were significantly intercorrelate d with and without age partialed out and (2) both verbal and visual-sp atial WM measures were significantly correlated with diverse achieveme nt and intelligence measures. Experiment 2 compared three age groups ( N = 192; 7-, 10-, and 13-year-olds) on working-memory performance task s under initial, enhanced (cued), and maintenance conditions. The resu lts supporting a general capacity system were that (1) age-related per formance differences in WM were found on all conditions and not isolat ed to specific processes, (2) the maintenance measures (high-load cond ition) predicted the variance better in age-related performance than p rocess measures, and (3) although individual differences in WM perform ance reflected two independent operations, these operations produced s imilar correlations to achievement within age groups. Overall, the res ults support a general capacity explanation of age-related and individ ual differences in children's WM performance.