Morphosyntactic development in German-speaking individuals with Down syndrome-longitudinal data.

Content Provider	Europe PMC
Author	Witecy, Bernadette Wimmer, Eva Neitzel, Isabel Penke, Martina
Copyright Year	2023
Abstract	IntroductionThe present study provides longitudinal data on the development of receptive and expressive grammar in children and adolescents with Down syndrome and addresses the role of nonverbal cognitive abilities and verbal short-term memory for morphosyntactic development.MethodSeventeen German-speaking individuals with Down syndrome (aged 4;6–17;1 years at first testing (T1)) were assessed twice, 4;4–6;6 years apart. For a subset of five participants, there was also a third assessment 2 years after the second. Receptive grammar, nonverbal cognition, and verbal short-term memory were tested using standardized measures. For expressive grammar, elicitation tasks were used to assess the production of subject-verb agreement and of wh-questions.ResultsAt group level, the participants showed a significant increase in grammar comprehension from T1 to T2. However, progress diminished with increasing chronological age. Notable growth could not be observed beyond the age of 10 years.With respect to expressive grammatical abilities, progress was limited to those participants who had mastered verbal agreement inflection around age 10 years. Individuals who did not master verbal agreement by late childhood achieved no progress in producing wh-questions, either.There was an increase in nonverbal cognitive abilities in the majority of participants. Results for verbal short-term memory followed a similar pattern as those for grammar comprehension. Finally, neither nonverbal cognition nor verbal short-term memory were related to changes in receptive or expressive grammar.DiscussionThe results point to a slowdown in the acquisition of receptive grammar which starts before the teenage years. For expressive grammar, improvement in wh-question production only occurred in individuals with good performance in subject-verb agreement marking, which suggests that the latter might have a trigger function for further grammatical development in German-speaking individuals with Down syndrome. The study provides no indication that nonverbal cognitive abilities or verbal short-term memory performance determined the receptive or expressive development. The results lead to clinical implications for language therapy.
Page Count	16
Journal	Frontiers in Psychology
Volume Number	14
PubMed Central reference number	PMC10321659
PubMed reference number	37416537
e-ISSN	16641078
DOI	10.3389/fpsyg.2023.1118659
Language	English
Publisher	Frontiers Media S.A.
Publisher Date	2023-06-21
Access Restriction	Open
Rights License	This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. Copyright © 2023 Witecy, Wimmer, Neitzel and Penke.
Subject Keyword	Down syndrome language development expressive grammar receptive grammar subject-verb agreement wh-questions verbal short-term memory longitudinal study
Content Type	Text
Resource Type	Article
Subject	Psychology