title: Patterns of developmental dyscalculia with or without dyslexia.
abstract: This study has been conducted in order to investigate the extent to which some characteristics of dyscalculia may be common to dyslexia. Seven multiple single-cases were studied: two children with dyslexia only, two with dyscalculia only, and three more children with comorbidity of dyslexia and dyscalculia. Each participant was assessed with a standardized comprehensive battery of arithmetical, reading, and cognitive tests. We observed that a clinical impairment in mental and written calculations, arithmetical facts retrieval, number comparison, number alignment, and identification of arithmetical signs may appear with a normal reading capacity and independently of a short-term verbal memory deficit. These findings add convergent support to the evidence mainly obtained from group comparisons that the more distinctive characteristics of dyscalculia are functionally independent of dyslexia.
authors.affiliation: Dipartimento di Psicologia, Generale Università di Padova, Padova, Italy. patrizio.tressoldi@unipd.it
authors.forename: Patrizio E
authors.initials: PE
authors.lastname: Tressoldi
authors.forename: Mario
authors.initials: M
authors.lastname: Rosati
authors.forename: Daniela
authors.initials: D
authors.lastname: Lucangeli
mesh_terms: D002648:Child; D003072:Cognition Disorders / Q000150:complications; D002658:Developmental Disabilities / Q000150:complications*; D004410:Dyslexia / Q000150:complications*; D005260:Female; D006801:Humans; D008297:Male; D008433:Mathematics; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D011340:Problem Solving / Q000502:physiology*; D011596:Psychomotor Disorders / Q000209:etiology