Exploring working memory in children with low arithmetical achievement.

This research aimed at exploring the working memory functions in children with low arithmetical achievement and normal reading, compared to age matched controls (mean age 9 years). All the children completed a series of working memory tasks, involving the central executive functions (using both linguistic and numerical material), the phonological loop (using words, pseudo-words and digits) and the visual sketchpad (using both static visualspatial patterns and visual-spatial sequences). Results indicated that poor arithmeticians performed worse than agematched controls in all the visual sketchpad tasks and in all the central executive tasks, whether they used linguistic or numerical material. On the contrary, the only phonological loop measure on which poor arithmeticians underachieved was the digit span forward. This selective impairment in the short-term recall of numerical material is explained as a difficulty in the access and retrieval of information from the numerical lexicon.