Oral language impairments in developmental disorders characterized by language strengths: A comparison of Asperger syndrome and nonverbal learning disabilities

Asperger syndrome (AS) and nonverbal learning disabilities (NLD) are developmental disorders in which linguistic ability is reported to be stronger than in disorders from which they must be distinguished for diagnosis. Children and adults with AS and NLD share pragmatic weaknesses, atypical social behaviours, and some cognitive features. To date, potential similarities between these disorders in oral language have not been directly examined in the literature. A review of the available research suggests that adequate structural language is another area of similarity for AS and NLD. However, systematic investigations of phonology, morphology, or syntax were not found; thus, the evidence for largely intact structural language in these disorders is indirect. The review also pointed to a common semantic profile across both disorders, characterized by strong vocabulary breadth in the face of limited depth and organization. These higher-order problems with semantics are proposed to be consistent with theoretical accounts of poor integrative abilities in AS and NLD, and to contribute to the well-documented pragmatic difficulties in these disorders.

► Critical review of empirical studies of structural language in Asperger syndrome and nonverbal learning disabilities, including gaps in the literature.
► Structural language appears to be as similar in these disorders as is pragmatics.
► Evidence for delays and possible ongoing but mild impairments of articulation in both disorder, but not for deficits in phonological awareness.
► Strengths in breadth and weaknesses in depth of semantic representations were seen, with the latter being suggested to be related to an impairment in semantic integration, implications for clinicians and researchers are discussed.