Testing the Continuum/Spectrum Model in Russian-Speaking Children With and Without Developmental Language Disorder

Area of Science:

• Linguistics
• Developmental Psychology
• Speech-Language Pathology

Background:

• Developmental Language Disorder (DLD) presents significant heterogeneity in symptom presentation.
• Previous research suggests a continuum/spectrum model best explains DLD symptom variability.
• This model may also encompass typically developing (TD) children with diverse language acquisition patterns.

Purpose of the Study:

• To test the hypothesis that a continuum/spectrum approach can explain language acquisition in both DLD and TD children.
• To investigate individual language profiles and deficits within a spectrum framework.
• To analyze language abilities in Russian-speaking children using a standardized assessment battery.

Main Methods:

• Assessed 53 Russian-speaking children with DLD (ages 4-7) and 53 age/gender-matched TD peers.
• Utilized the Russian Child Language Assessment Battery (RuCLAB) with 11 subtests across four language levels (production/comprehension).
• Employed k-means clustering on RuCLAB scores to identify distinct child groups.

Main Results:

• Two mixed clusters emerged: Group 1 (higher scores: 45 TD, 24 DLD) and Group 2 (lower scores: 8 TD, 29 DLD).
• Group 1 children typically showed deficits at one language level, while Group 2 struggled across multiple levels.
• DLD children in both groups exhibited greater sensitivity to linguistic features like word length and noun case compared to TD children.

Conclusions:

• The study confirms that diagnosed DLD children can perform similarly to TD children, and some TD children may exhibit DLD-like performance.
• Findings strongly support the continuum/spectrum model, indicating language skills vary across a spectrum in preschool children.
• Comprehensive language assessment across all levels is crucial for accurately describing a child's language profile.