Individual Differences in Verb Bias Sensitivity in Children and Adults With Developmental Language Disorder

The association between statistical learning and language development during childhood: A scoping review

The statistical account of language acquisition asserts that language is learned through computations on the statistical regularities present in natural languages. This type of account can predict variability in language development measures as arising from individual differences in extracting this statistical information. Given that statistical learning has been attested across different domains and modalities, a central question is which modality is more tightly yoked with language skills. The results of a scoping review, which aimed for the first time at identifying the evidence of the association between statistical learning skills and language outcomes in typically developing infants and children, provide preliminary support for the statistical learning account of language acquisition, mostly in the domain of lexical outcomes, indicating that typically developing infants and children with stronger auditory and audio-visual statistical learning skills perform better on lexical competence tasks. The results also suggest that the relevance of statistical learning skills for language development is dependent on sensory modality.

Moment-to-Moment Processing of Complex Sentences by Adults with and without Developmental Language Disorder

INTRODUCTION

. Limited evidence suggests that adults with developmental language disorder (DLD) take different information into account as they process sentences as compared to peers with typical language. The purpose of this study was to evaluate how two factors affect sentence processing in adults with DLD: online storage costs and lexical expectations created by nouns.

METHODS

. Forty-three adults, 21 with DLD, listened to complex sentences presented word-by-word, and their listening times were recorded. The sentences included either object relative clauses or sentential complements which differed in online storage demands. The main clause subject nouns differed in co-occurrence frequency with "that" in sentences produced by typical adults. Participants completed a running span task to assess verbal working memory capacity.

RESULTS

. Mixed effects models found differences by sentence region. Participants with DLD processed embedded clause verbs faster than participants with typical language, and poorer language ability was associated with faster processing of conjunctions "that" and "which." Participants with greater verbal working memory capacity or typical language were affected by noun co-occurrence frequencies but those with lower working memory or DLD were not.

CONCLUSIONS

. The results align with prior findings that verbal working memory capacity influences what information affects moment-to-moment sentence processing. Those with greater capacity appeared to be more affected by temporary ambiguity. As compared to adults with typical language, processing times of adults with DLD were less sensitive to information on words that frequently co-occur with nouns. This aligns with prior findings suggesting that adults with DLD are less sensitive to the frequency of the structures and arguments that co-occur with verbs.

Statistical Learning and Language Impairments: Toward More Precise Theoretical Accounts

Statistical-learning (SL) theory offers an experience-based account of typical and atypical spoken and written language acquisition. Recent work has provided initial support for this view, tying individual differences in SL abilities to linguistic skills, including language impairments. In the current article, we provide a critical review of studies testing SL abilities in participants with and without developmental dyslexia and specific language impairment and discuss the directions that this field of research has taken so far. We identify substantial vagueness in the demarcation lines between different theoretical constructs (e.g., “statistical learning,” “implicit learning,” and “procedural learning”) as well as in the mappings between experimental tasks and these theoretical constructs. Moreover, we argue that current studies are not designed to contrast different theoretical approaches but rather test singular confirmatory predictions without including control tasks showing normal performance. We end by providing concrete suggestions for how to advance research on SL deficits in language impairments.