The impact of phonological complexity on past tense inflection in children with Grammatical-SLI

Abstract

English-speaking children with Specific Language Impairment (SLI) variably produce inflected and bare stem forms in obligatory past tense contexts. Researchers have not reached consensus as to whether the underlying deficit is morphosyntactic or morphophonological in nature. The Computational Grammatical Complexity (CGC) Hypothesis takes a different tack: it hypothesizes that for children with a particular form of SLI, Grammatical-SLI, the deficit is in representing linguistic structural complexity in at least three components of the computational grammatical systemsyntax, morphology and phonology. Deficits in all these components are predicted to impact on regular past tense formation. The impact of syntactic and morphological complexity on G-SLI children's realization of tense has been tested previously. Here we complete the picture by considering phonological effects on their production of regular past tense inflection. Using a past tense elicitation task where we manipulate the phonological complexity of the inflected verb end, we show that, as predicted, verb-end phonological complexity impacts on suffixation: G-SLI children are less likely to suffix stems when the inflected form ends in a consonant cluster. Typically developing controls show no such effect. The results of this study highlight the need to consider the independent contributions of language components to impaired and normal performance.

Phonological Constraints on Children’s Production of English Third Person Singular – s

“…These results indicate that the production of the third person singular morpheme in typically developing children is subject to coda complexity effects similar to those reported for older grammatical-SLI children's production of past tense morphemes (Marshall & van der Lely, 2007).…”

“…Most relevant to the present study is an investigation of 9-to16-year-old grammatical-SLI children, where Marshall and van der Lely (2007) investigated the impact of the number of consonants at the end of the inflected verb on the production of past tense inflections. Using an elicited production task, participants were found to have increasing difficulty producing past tense morphemes as word-final consonant complexity increased from one to three consonants (e.g., sewed /soOd/, yelled / jeld/, danced /daenst/).…”

The prosodic (re)organization of children's early English articles

“…hits) (e.g. Marshall & van der Lely, 2007 ;Song, Sundara & Demuth, in submission). Thus, although these children can produce coda clusters in isolation, these grammatical morphemes are more likely to be produced in phonologically simple, or unmarked contexts (e.g.…”

Heather van der Lely and developmental language disorders: Introduction to the special issue

“…Inflectional morphology in children with SLI has an even more protracted period of development, if it is mastered at all (van der Lely & Ullman, 2001), and the Prosodic Licensing Hypothesis also makes predictions for SLI. In their review, Demuth and Tomas draw on their own work and on previous work by Heather that has investigated the interaction between phonology and morphology (Marshall & van der Lely, 2007b, 2012.…”