A profile of expressive inflectional morphology in early school-age children with developmental language disorder

ABSTRACT

Previous research has established that children with developmental language disorder (DLD) have difficulties producing inflectional morphology, in particular, finiteness marking. However, other categories of inflectional morphology, such as possessive ‘s nominal inflection remain relatively unexplored. Analyses of the characteristics for marking inflection, such as allomorphic categories, may increase our understanding of patterns within disordered grammar to inform the design of interventions and target selection. Data from n = 30 early school-aged children (M = 75 months, SD = 3.38, range = 69–81 months) with DLD were analysed to develop a profile of inflectional morphology skills. Morphological categories included expressive regular past tense, third person singular, and possessive ‘s. Skills were profiled using an elicitation task. The relationships between expressive morphosyntax, and phonological short-term memory and working memory were also explored. Children demonstrated low accuracy in performance across all inflectional categories, including possessive ‘s. There were no significant differences between productions of different morphemes, but syllabic allomorphs ([əd]; [əz]) were produced with significantly lower accuracy than segmental allomorphs ([d], [t]; [z], [s]) across all morphological categories. All correlations between expressive morphosyntax and measures of memory were non-significant. Children with DLD show broad deficits in the ability to mark for inflection, including possessive ‘s; this has implications for theories explaining DLD. Findings may contribute to the design of urgently needed interventions for this clinical population.

KEYWORDS:

• Developmental language disorder
• morphosyntax
• verbal inflection
• nominal inflection

Acknowledgments

Thanks to the specialised school, participants, and staff. Thanks to Dr Karen Smith-Lock for supporting the use of the Grammar Elicitation Test for the purpose of this study.

Disclosure of potential conflicts of interest

The authors declare that there are no relevant conflicts of interest.

Correction Statement

This article has been corrected with minor changes. These changes do not impact the academic content of the article.

Notes

¹ It is acknowledged that previous research has used various terms to describe childhood language disorder in the absence of other biomedical conditions, such as specific language impairment. The term developmental language disorder (DLD) is used throughout this paper, in line with recommendations from a recent international consensus study (Bishop et al., 2017).

Additional information

Funding

The authors acknowledge the contribution of an Australian Government Research Training Program Scholarship in supporting this research.