A cognitive characterization of dyscalculia in Turner syndrome

• Published in: Neuropsychologia Vol. 42; no. 3; pp. 288 - 298
• Main Authors: Bruandet, Marie, Molko, Nicolas, Cohen, Laurent, Dehaene, Stanislas
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 2004; Elsevier Science
• Subjects: Adolescent; Adult; Adult and adolescent clinical studies; Biological and medical sciences; Cognition - physiology; Developmental dyscalculia; Estrogen; Female; Humans; Learning Disorders - complications; Learning Disorders - genetics; Mathematics; Medical sciences; Organic mental disorders. Neuropsychology; Parietal; Problem Solving - physiology; Psychology. Psychoanalysis. Psychiatry; Psychopathology. Psychiatry; Reaction Time - physiology; Reference Values; Turner Syndrome - complications; Turner Syndrome - genetics; Turner Ulrich syndrome; X chromosome; Parietal; Turner Ulrich syndrome; Developmental dyscalculia; Estrogen; X chromosome; Chromosomal aberration; Human; Dysgenesia; Cognitive disorder; Sexual differentiation disorder; Turner syndrome; Ovarian hormone; Female genital diseases; Malformation; Gonad; Female; Dyscalculia; Sex steroid hormone
• ISSN: 0028-3932; 1873-3514
• DOI: 10.1016/j.neuropsychologia.2003.08.007

Current theories of number processing postulate that the human abilities for arithmetic are based on cerebral circuits that are partially laid down under genetic control and later modified by schooling and education. This view predicts the existence of genetic diseases that interfere specifically with components of the number system. Here, we investigate whether Turner syndrome (TS) corresponds to this definition. TS is a genetic disorder which affects one woman in 2500 and is characterized by partial or complete absence of one X chromosome. In addition to well-characterized physical and hormonal dysfunction, TS patients exhibit cognitive deficits including dyscalculia. We tested 12 women with Turner syndrome and 13 control subjects on a cognitive battery including arithmetical tests (addition, subtraction, multiplication, division) as well as tests of the understanding of numerosity and quantity (cognitive estimation, estimation, comparison, bisection, subitizing/counting). Impairments were observed in cognitive estimation, subitizing, and calculation. We examine whether these deficits can be attributed to a single source, and discuss the possible implications of hormonal and genetic factors in the neuropsychological profile of TS patients.