Uniqueness of the visual processing disabilities in children with nonverbal learning disabilities and their relationship to performance in arithmetic

grantor: University of TorontoVisual processing difficulties have been described as a core problem of children with nonverbal learning disabilities (NLD; Rourke, 1989), but the specific nature of these difficulties has received little systematic investigation. The younger the age at which these kinds of difficulties are identified, the better the opportunity for successful intervention (Rourke, 1989). The present study systematically compared the simple and complex visuoperceptual and visual-spatial abilities of 6-year-old boys with NLD ('n' = 13) to a matched control group of boys with other learning disabilities (CLD) and to normative scores. A profile of strong average abilities on a simple discrimination task but relative visual-spatial weaknesses was unique to the NLD group, as was significantly poorer ('p' <= 5.01) performance on the mom complex mental rotation task. The visual processing abilities of children with NLD were positively associated with their arithmetic scores, but no significant correlations were found for the CLD group.M.A