Finite verb morphology and phonological length in the speech of children with specific language impairment

Children with specific language impairment (SLI) usually differ from younger peers in their use of grammatical morphemes pertaining to tense and agreement. The word-final consonant status of many of these morphemes has prompted researchers to verify that the children under study are capable of producing these consonants in monomorphemic words (e.g. hand, box). However, such a measure does not ensure that the children with SLI are capable of producing words of sufficient length to support grammatical morpheme use. To examine the possible influence of this factor, we employed Ingram's phonological mean length of utterance (PMLU) as the basis for matching a group of preschoolers with SLI and younger typically developing peers. The children's use of tense/agreement morphemes was then determined. The findings indicated that despite the comparable PMLUs of the two groups, the children with SLI were more limited in their use of tense/agreement morphology than the younger peers.