Visual-spatial performance deficits in children with neurofibromatosis type-1

Neurofibromatosis type-1 (NF1) is a common genetic disorder associated with a variety of medical complications, cognitive impairments, and behavioral problems including a high incidence of Attention Deficit Hyperactivity Disorder (ADHD). The current study examined the hypotheses that deficits in visual-spatial/motor abilities enable one to discriminate and classify children with NF1 (n = 101) compared to control children (n = 37), beyond effects secondary to parent reported ADHD symptomology. Discriminant analysis showed a multivariate combination of visual-spatial/motor ability tests (Judgment of Line Orientation, Block Design subtest of the WISC-III, Recognition-Discrimination Test, Beery Visual-Motor Integration Test) to be a significant predictor of NF1 diagnostic status (P = 0.0000004; canonical R(2) = 0.2306). A significantly greater degree of ADHD behavior was found in the NF1 group, and a discriminant analysis using ADHD residualized visual-spatial motor scores indicated that the combination of tests continued to be a significant predictor of group membership after the level of ADHD behavior was controlled (P = 0.00002 and a canonical R(2) = 0.1818). This combination of tests proved to be a strong discriminator of NF1. It correctly identified 90% of individuals with the diagnosis, and may be useful to educators to provide assistance and alternatives to minimize the impact of learning problems in those with either known or suspected NF1.