Research‎ > ‎

Causes

doi:10.1016/j.jecp.2009.03.006 | How to Cite or Link Using DOI
Copyright © 2009 Elsevier Inc. All rights reserved.
   Cited By in Scopus (7)
  Permissions & Reprints

Dyslexia and dyscalculia: Two learning disorders with different cognitive profiles
Purchase the full-text article

Karin LanderlaCorresponding Author Contact InformationE-mail The Corresponding Author, Barbara Fusseneggerb, Kristina Mollb and Edith Willburgerb

aDepartment of Psychology, University of Tuebingen, 72072 Tuebingen, Germany

bDepartment of Psychology, University of Salzburg, 5020 Salzburg, Austria

Received 13 August 2008;  
revised 9 March 2009.  
Available online 26 April 2009. 

Abstract

This study tests the hypothesis that dyslexia and dyscalculia are associated with two largely independent cognitive deficits, namely a phonological deficit in the case of dyslexia and a deficit in the number module in the case of dyscalculia. In four groups of 8- to 10-year-olds (42 control, 21 dyslexic, 20 dyscalculic, and 26 dyslexic/dyscalculic), phonological awareness, phonological and visual–spatial short-term and working memory, naming speed, and basic number processing skills were assessed. A phonological deficit was found for both dyslexic groups, irrespective of additional arithmetic deficits, but not for the dyscalculia-only group. In contrast, deficits in processing of symbolic and nonsymbolic magnitudes were observed in both groups of dyscalculic children, irrespective of additional reading difficulties, but not in the dyslexia-only group. Cognitive deficits in the comorbid dyslexia/dyscalculia group were additive; that is, they resulted from the combination of two learning disorders. These findings suggest that dyslexia and dyscalculia have separable cognitive profiles, namely a phonological deficit in the case of dyslexia and a deficient number module in the case of dyscalculia.

Keywords: Dyslexia; Dyscalculia; Phonological deficits; Number module; Magnitude comparison; Mental number line

Corresponding Author Contact InformationCorresponding author. Fax: +49 7071 55 24 13.