An investigation of the possible causes of arithmetic difficulties in children with dyscalculia

It is often reported in the literature that one of the main difficulties of children with dyscalculia is retrieval of arithmetic facts. The goal of this paper is to examine two different explanations that are put forward in order to account for these difficulties, namely a hypersensitivity to interference and a working memory deficit. Five children aged between 10 and 12 years presenting dyscalculia and fifty-one control children of the same age were compared on their performance in addition and multiplication. Our results show that differences in performance between the two groups of children were significant for addition but not for multiplication. Moreover, concerning additions, children with dyscalculia presented more difficulties for non-tie (e.g., 3 + 4) than tie problems (e.g., 3 + 3). Altogether, our results support the fact that, in our sample, the difficulties encountered by children with dyscalculia in arithmetic were due to working memory limitations or, alternatively, to a deficit in the automatization of counting procedures.