RESUMO
Several copy number variants have been associated with neuropsychiatric disorders and these variants have been shown to also influence cognitive abilities in carriers unaffected by psychiatric disorders. Previously, we associated the 15q11.2(BP1-BP2) deletion with specific learning disabilities and a larger corpus callosum. Here we investigate, in a much larger sample, the effect of the 15q11.2(BP1-BP2) deletion on cognitive, structural and functional correlates of dyslexia and dyscalculia. We report that the deletion confers greatest risk of the combined phenotype of dyslexia and dyscalculia. We also show that the deletion associates with a smaller left fusiform gyrus. Moreover, tailored functional magnetic resonance imaging experiments using phonological lexical decision and multiplication verification tasks demonstrate altered activation in the left fusiform and the left angular gyri in carriers. Thus, by using convergent evidence from neuropsychological testing, and structural and functional neuroimaging, we show that the 15q11.2(BP1-BP2) deletion affects cognitive, structural and functional correlates of both dyslexia and dyscalculia.
Assuntos
Cognição/fisiologia , Variações do Número de Cópias de DNA/genética , Discalculia/genética , Dislexia/genética , Deficiência Intelectual/genética , Adolescente , Adulto , Idoso , Aberrações Cromossômicas , Deleção Cromossômica , Cromossomos Humanos Par 15/genética , Deficiências do Desenvolvimento/genética , Feminino , Neuroimagem Funcional/métodos , Neuroimagem Funcional/normas , Heterozigoto , Humanos , Islândia/epidemiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos/normas , Fenótipo , Lobo Temporal/anatomia & histologia , Lobo Temporal/diagnóstico por imagem , Adulto JovemRESUMO
The incidence of head trauma (ICD9 850-854) among children in the Reykjavík area, aged 0-14 years, was studied over a 5-year period, 1987-1991, using hospital records. On average, 72 children with head trauma were admitted to hospital each year, indicating an annual incidence of 1.70 per 1000 population. Fourteen percent of children admitted to hospital with head trauma suffered the more severe forms of brain injury (ICD9 851-854) (annual incidence of 0.28 per 1000). Seven children died from brain injury, indicating an annual death rate of 0.03 per 1000. Falls were the most common cause of head trauma (62%), followed by traffic accidents (19%). On average, one to two severely brain-injured children received rehabilitation each year.