Abstract
This is a clinical case study of a 4-year-old boy (H.N.) who demonstrates an infrequently studied ‘semantic-pragmatic’ type of specific language impairment (SLI). In contrast to the disturbances of linguistic form that characterize the most frequently reported type of SLI, the semantic-pragmatic syndrome is characterized mostly by ‘inappropriate’ language use. A cognitive explanation has been proposed that accounts for all instances of inappropriate language thus far studied in this population. An expressive linguistic explanation has also been proposed that accounts for some instances of inappropriate language, but not for irrelevant comments or inappropriate responses to questions. I propose that a receptive linguistic explanation can account for inappropriate responses to questions. Thus, a linguistic explanation with receptive and expressive components could account for all but a few semantic-pragmatic behaviours previously accounted for by the cognitive explanation. To test this proposal, H.N.‘s responses to questions were studied in relation to the interrogative forms (Wh-words) used in the questions addressed to him. The results indicate that H.N. failed to comprehend a specific Wh-word that was associated with a set of relational concepts, but he understood other words that expressed an overlapping set of concepts. Thus, instances of inappropriate language use that appear to express disordered concepts may reflect receptive linguistic deficits instead. To the extent that these findings can be extended and replicated, they suggest that the semantic-pragmatic type of SLI is closely related to the type of SLI that affects morphology and syntax. The possible unity underlying the two types of SLI is discussed in relation to a phonological storage/access theory that has recently been proposed to account for morphosyntactic deficits in preschool children with language disorders.