The pattern of neuropsychological assets and deficits that characterize a nonverbal learning disability (NLD) is evident in a wide variety of neurological diseases and dysfunctions. Numerous studies that have focused on neuropsychology, development, and cognition have resulted in a hierarchy of disorders and disabilities. Research has found that hydrocephalus related to spina bifida, and other neurological conditions, predispose the individual affected to an NLD. This chapter is organized to reflect the extent to which certain biological conditions give rise to the features characteristic of NLD with a three-level hierarchy wherein 1evel 1 disorders are the closest phenotypically to NLD. Discussion then moves to levels 2 and 3 where presentations of the syndrome are less obvious. Characteristic features of each disorder, relevant research findings, and the involvement of damaged, destroyed, or dysfunctional white matter in manifestation of the NLD syndrome are discussed.
Estimated Prevalence of Nonverbal Learning Disability Among North American Children and Adolescents
