Speed of processing and reading disability: a cross-linguistic investigation of dyslexia and borderline intellectual functioning.

Journal article

English and Italian children with dyslexia were compared with children with reading difficulties associated with low-IQ on tests of simple and choice RT, and in number and symbol scanning tasks. On all four speed-of-processing tasks, children with low-IQ responded more slowly than children with dyslexia and age-controls. In the choice RT task, the performance of children with low-IQ was also less accurate than that of children of normal IQ, consistent with theories linking processing speed limitations with low-IQ. These findings support the hypothesis that dyslexia is a specific cognitive deficit that can arise in the context of normal IQ and normal speed of processing. The same cognitive phenotype was observed in readers of a deep (English) and a shallow (Italian) orthography.

Authors: Bonifacci, P; Snowling, M

• Publication status: Published
• Journal: Cognition
• Volume: 107
• Issue: 3
• Pages: 999-1017
• Publication date: 2008-06-01
• DOI: 10.1016/j.cognition.2007.12.006
• EISSN: 1873-7838
• ISSN: 0010-0277
• Language: English
• Keywords: Reaction Time; Female; Phenotype; Cross-Cultural Comparison; Child; Recognition (Psychology); Intellectual Disability; Dyslexia; Severity of Illness Index; Adolescent; Humans; Male