The understanding of complex syntax in children with Down syndrome

Journal article

Background

Down syndrome (DS) is associated with poor language skills that seem disproportionate to general nonverbal ability, but the nature and causes of this deficit are unclear. We assessed how individuals with DS understand complex linguistic constructions, and considered how cognitive ability, memory and hearing level impact the ability of those with DS to process these sentence types.

Methods

There were three groups participating in the study: children with DS (n = 33) and two control groups composed of children with cognitive impairment of unknown aetiology (CI) (n = 32) and children with typical development (n = 33). Both groups were matched to those with DS on cognitive ability. Using a newly devised animation task, we examined how well individuals with DS (n = 33) could understand relative clauses, complement clauses and adverbial clauses compared to children with CI and typically developing controls. Participants also completed the Test for the Reception of Grammar-2, three measures of memory (forward and backward digit recall, visuo-spatial memory) and a hearing screen.

Results

Results indicated that (1) with the exception of intransitive subject relative clauses, children with DS performed at floor on all other complex sentences, (2) they performed at a significantly lower level than both control groups, and (3) DS status accounted for a significant proportion of the variance over and above memory skills.

Conclusions

Our findings suggest that children with DS have a disproportionate difficulty understanding complex sentences compared to two control groups matched on mental age. Furthermore, their understanding of syntax is not completely explained by poor cognitive or memory skills, rather it appears to be a specific deficit that may distinguish children with DS from other neurodevelopmental disorders.

Authors: Frizelle, P; Thompson, P; Duta, M; Bishop, D

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Wellcome Trust
• Journal: Wellcome Open Research
• Volume: 3
• Pages: 140
• Publication date: 2018-11-01
• Acceptance date: 2018-11-01
• DOI: 10.12688/wellcomeopenres.14861.2
• EISSN: 2398-502X
• Keywords: relative clause; children; complement clause; receptive language; Down syndrome; Complex syntax; adverbial clause