Arithmetic skills and their cognitive correlates in children with acquired and congenital brain disorder.

Arithmetic skills and their cognitive correlates were studied in 24 children with myelomeningocele and shunted hydrocephalus (MM), 27 children with severe traumatic brain injuries (TBI), and 26 children with orthopedic injuries (OI). Their average age was 11.56 years (SD = 2.36). They completed the WRAT-3 Arithmetic subtest and a subtraction task consisting of 20 problems of varying difficulty, as well as measures of working memory, declarative memory, processing speed, planning skills, and visuospatial abilities. The MM group performed more poorly on the WRAT-3 Arithmetic subtest and the subtraction task than the other two groups, which did not differ from each other on either measure. The groups did not differ in the number of math fact errors or visual-spatial errors on the subtraction task, but the MM group made more procedural errors than the OI group. The five cognitive abilities explained substantial variance in performance on both arithmetic tests; processing speed, working memory, declarative memory, and planning accounted for unique variance. Exploratory analyses showed that the cognitive correlates of arithmetic skills varied across groups and ages. Congenital and acquired brain disorders are associated with distinct patterns of arithmetic skills, which are related to specific cognitive abilities.