Previous research has failed to show a relation between children's working memory and performance on the phonological sound categorization task (M. J. Snowling, C. Hulme, A. Smith, & J. Thomas, 1994). However, the test used to assess working memory in that experiment was more comparable to a short-term memory task, which assesses storage capacity, than to a working memory task, which has both storage and processing components. In the present study, we compared the predictive power of both types of memory tasks on 2 measures of phonological awareness, the sound categorization task and a phoneme deletion task, in 7- and 8-year-olds (mean age = 8 years 1 month). The children's reading ability was also assessed. Fixed-order multiple-regression analyses showed that the sound categorization task has a higher working memory demand than the phoneme deletion task: Working memory predicted independent variance in performance only on the sound categorization task. The short-term memory task did not account for significant independent variance in performance on either of the measures of phonological awareness.
Copyright 2000 Academic Press.