Complex grammar in Williams syndrome.

Area of Science:

• Linguistics
• Developmental Psychology
• Neuroscience

Background:

• Williams syndrome (WS) is a genetic disorder associated with cognitive and language impairments.
• Typical language development involves mastering grammatical structures like binding and raising by specific ages.
• Previous research suggests grammatical development in WS may be delayed but its completeness is uncertain.

Purpose of the Study:

• To investigate the knowledge of binding and raising in children with Williams syndrome (WS) compared to typically developing (TD) controls.
• To determine if grammatical development in WS follows a similar, albeit delayed, trajectory to that of TD individuals.
• To identify specific grammatical structures that present unique challenges for individuals with WS.

Main Methods:

• The study compared two groups of children with WS (6-12 and 12-16 years old) to age- and ability-matched TD controls.
• Participants were assessed on their understanding of binding principles (reflexives) and raising constructions.
• Cognitive abilities, including non-verbal mental age (MA), verbal MA, and grammar, were used for matching.

Main Results:

• Knowledge of reflexive binding was intact in all participants with WS, consistent with prior findings.
• Children with WS under 12 demonstrated poorer performance on personal pronouns compared to younger TD controls, suggesting a novel delay in coreference constraints.
• Both WS groups exhibited extremely limited comprehension of raised structures, indicating a significant delay in this grammatical aspect.

Conclusions:

• Grammatical development in WS, like in TD populations, shows distinct maturation stages for different structures.
• Reflexive binding appears to be acquired earlier than coreference constraints in WS.
• The development of raising constructions in WS is exceptionally delayed and may not be fully attained, potentially linked to maturational deficits in A-chains or phases.