Identifying Linguistic Markers of French-Speaking Teenagers With Developmental Language Disorder: Which Tasks Matter?

Area of Science:

• Linguistics
• Developmental Psychology
• Clinical Linguistics

Background:

• Developmental Language Disorder (DLD) affects language acquisition.
• In French, morphosyntax is not consistently identified as a weakness in preschoolers with DLD, unlike in English.
• Subject-verb agreement is expected to emerge as a challenge in later childhood, potentially marking DLD in adolescents.

Purpose of the Study:

• To identify reliable tasks that differentiate French-speaking adolescents with DLD from those with typical language (TL).
• To determine which linguistic domains represent significant weaknesses for adolescents with DLD.

Main Methods:

• Administered 20 subtasks assessing linguistic and phonological working memory skills to 17 adolescents with DLD and 20 with TL.
• Utilized robust statistics to select discriminating subtasks and assess diagnostic accuracy.
• Employed a multivariable model to identify key contributing subtasks for DLD identification.

Main Results:

• Seven subtasks effectively discriminated between the DLD and TL groups.
• Three subtasks demonstrated outstanding diagnostic accuracy: Sentence Recall, a lexicosemantic task, and a subject-verb agreement production task.
• Subject-verb agreement production was the most significant contributor in the multivariable model.

Conclusions:

• Lexicosemantic and morphosyntactic tasks are vital for identifying DLD in French-speaking teenagers.
• Morphosyntax should be recognized as a significant area of difficulty for French-speaking adolescents with DLD.