Children with specific language impairment show rapid, implicit learning of stress assignment rules

What Children with Developmental Language Disorder Teach Us About Cross-Situational Word Learning

Children with developmental language disorder (DLD) served as a test case for determining the role of extant vocabulary knowledge, endogenous attention, and phonological working memory abilities in cross‐situational word learning. First‐graders (M_age = 7 years; 3 months), 44 with typical development (TD) and 28 with DLD, completed a cross‐situational word‐learning task comprised six cycles, followed by retention tests and independent assessments of attention, memory, and vocabulary. Children with DLD scored lower than those with TD on all measures of learning and retention, a performance gap that emerged in the first cycle of the cross‐situational protocol and that we attribute to weaknesses in initial encoding. Over cycles, children with DLD learned words at a similar rate as their TD peers but they were less flexible in their strategy use, demonstrating a propose‐but‐verify approach but never a statistical aggregation approach. Also, they drew upon different mechanisms to support their learning. Attention played a greater role for the children with DLD, whereas extant vocabulary size played a greater role for the children with TD. Children navigate the problem space of cross‐situational learning via varied routes. This conclusion is offered as motivation for theorists to capture all learners, not just the most typical ones.

Language Intervention Isn't Just Spoken: Assessment and Treatment of a Deaf Signing Child With Specific Language Impairment

Purpose This case study describes the language evaluation and treatment of a 5-year-old boy, Lucas, who is Deaf, uses American Sign Language (ASL), and presented with a language disorder despite native access to ASL and no additional diagnosis that would explain the language difficulties. Method Lucas participated in an evaluation where his nonverbal IQ, fine motor, and receptive/expressive language skills were assessed. Language assessment included both formal and informal evaluation procedures. Language intervention was delivered across 7 weeks through focused stimulation. Results Evaluation findings supported diagnosis of a language disorder unexplained by other factors. Visual analysis revealed an improvement in some behaviors targeted during intervention (i.e., number of different verbs and pronouns), but not others. In addition, descriptive analysis indicated qualitative improvement in Lucas' language production. Parent satisfaction survey results showed a high level of satisfaction with therapy progress, in addition to a belief that Lucas improved in language areas targeted. Conclusions This study adds to the growing body of literature that unexplained language disorders in signed languages exist and provides preliminary evidence for positive outcomes from language intervention for a Deaf signing child. The case described can inform professionals who work with Deaf signing children (e.g., speech-language pathologists, teachers of the Deaf, and parents of Deaf children) and serve as a potential starting point in evaluation and treatment of signed language disorders. Supplemental Material https://doi.org/10.23641/asha.16725601.

Not All Procedural Learning Tasks Are Difficult for Adults With Developmental Language Disorder

Purpose The experiment reported here compared two hypotheses for the poor statistical and artificial grammar learning often seen in children and adults with developmental language disorder (DLD; also known as specific language impairment). The procedural learning deficit hypothesis states that implicit learning of rule-based input is impaired, whereas the sequential pattern learning deficit hypothesis states that poor performance is only seen when learners must implicitly compute sequential dependencies. The current experiment tested learning of an artificial grammar that could be learned via feature activation, as observed in an associatively organized lexicon, without computing sequential dependencies and should therefore be learnable on the sequential pattern learning deficit hypothesis, but not on the procedural learning deficit hypothesis. Method Adults with DLD and adults with typical language development (TD) listened to consonant-vowel-consonant-vowel familiarization words from one of two artificial phonological grammars: Family Resemblance (two out of three features) and a control (exclusive OR, in which both consonants are voiced OR both consonants are voiceless) grammar in which no learning was predicted for either group. At test, all participants rated 32 test words as to whether or not they conformed to the pattern in the familiarization words. Results Adults with DLD and adults with TD showed equal and robust learning of the Family Resemblance grammar, accepting significantly more conforming than nonconforming test items. Both groups who were familiarized with the Family Resemblance grammar also outperformed those who were familiarized with the OR grammar, which, as predicted, was learned by neither group. Conclusion Although adults and children with DLD often underperform, compared to their peers with TD, on statistical and artificial grammar learning tasks, poor performance appears to be tied to the implicit computation of sequential dependencies, as predicted by the sequential pattern learning deficit hypothesis.

Towards a theory of individual differences in statistical learning

In recent years, statistical learning (SL) research has seen a growing interest in tracking individual performance in SL tasks, mainly as a predictor of linguistic abilities. We review studies from this line of research and outline three presuppositions underlying the experimental approach they employ: (i) that SL is a unified theoretical construct; (ii) that current SL tasks are interchangeable, and equally valid for assessing SL ability; and (iii) that performance in the standard forced-choice test in the task is a good proxy of SL ability. We argue that these three critical presuppositions are subject to a number of theoretical and empirical issues. First, SL shows patterns of modality- and informational-specificity, suggesting that SL cannot be treated as a unified construct. Second, different SL tasks may tap into separate sub-components of SL that are not necessarily interchangeable. Third, the commonly used forced-choice tests in most SL tasks are subject to inherent limitations and confounds. As a first step, we offer a methodological approach that explicitly spells out a potential set of different SL dimensions, allowing for better transparency in choosing a specific SL task as a predictor of a given linguistic outcome. We then offer possible methodological solutions for better tracking and measuring SL ability. Taken together, these discussions provide a novel theoretical and methodological approach for assessing individual differences in SL, with clear testable predictions.This article is part of the themed issue 'New frontiers for statistical learning in the cognitive sciences'.

Perspectives on the rhythm-grammar link and its implications for typical and atypical language development

This paper reviews the mounting evidence for shared cognitive mechanisms and neural resources for rhythm and grammar. Evidence for a role of rhythm skills in language development and language comprehension is reviewed here in three lines of research: (1) behavioral and brain data from adults and children, showing that prosody and other aspects of timing of sentences influence online morpho-syntactic processing; (2) comorbidity of impaired rhythm with grammatical deficits in children with language impairment; and (3) our recent work showing a strong positive association between rhythm perception skills and expressive grammatical skills in young school-age children with typical development. Our preliminary follow-up study presented here revealed that musical rhythm perception predicted variance in 6-year-old children's production of complex syntax, as well as online reorganization of grammatical information (transformation); these data provide an additional perspective on the hierarchical relations potentially shared by rhythm and grammar. A theoretical framework for shared cognitive resources for the role of rhythm in perceiving and learning grammatical structure is elaborated on in light of potential implications for using rhythm-emphasized musical training to improve language skills in children.

Differences in the performance of children with specific language impairment and their typically developing peers on nonverbal cognitive tests: a meta-analysis

PURPOSE

This study used meta-analysis to investigate the difference in nonverbal cognitive test performance of children with specific language impairment (SLI) and their typically developing (TD) peers.

METHOD

The meta-analysis included studies (a) that were published between 1995 and 2012 of children with SLI who were age matched (and not nonverbal cognitive matched) to TD peers and given a norm-referenced nonverbal cognitive test and (b) that reported sufficient data for an effect size analysis. Multilevel modeling was used to examine the performance of children with SLI relative to their typically developing, age-matched peers on nonverbal IQ tests.

RESULTS

Across 138 samples from 131 studies, on average children with SLI scored 0.69 standard deviations below their TD peers on nonverbal cognitive tests after adjusting for the differences in the tests used, the low-boundary cutoff scores, the age of the participants, and whether studies matched the two groups on socioeconomic status.

DISCUSSION

The lower performance of children with SLI relative to TD children on nonverbal IQ tests has theoretical implications for the characterization of SLI and clinical and political implications regarding how nonverbal cognitive tests are used and interpreted for children with this disorder.

What influences children's conceptualizations of language input?

PURPOSE

Children learning language conceptualize the nature of input they receive in ways that allow them to understand and construct utterances they have never heard before. This study was designed to illuminate the types of information children with and without specific language impairment (SLI) focus on to develop their conceptualizations and whether they can rapidly shift their initial conceptualizations if provided with additional input.

METHOD

In 2 studies, preschool children with and without SLI were exposed to an artificial language, the characteristics of which allowed for various types of conceptualizations about its fundamental properties. After being familiarized with the language, children were asked to judge test strings that conformed to the input in 1 of 4 different ways.

RESULTS

All children preferred test items that reflected a narrow conceptualization of the input (i.e., items most like those heard during familiarization). Children showed a strong preference for phonology as a defining property of the artificial language. Restructuring the input to the child could induce them to track word order information as well.

CONCLUSION

Children tend toward narrow conceptualizations of language input, but the nature of their conceptualizations can be influenced by the nature of the input they receive.

Word stress processing in specific language impairment: auditory or representational deficits?

Word stress processing has repeatedly been reported to be affected in specific language impairment (SLI) with potential consequences for various aspects of language development. However, it still remains unresolved whether word stress impairments in SLI are due to deficits in basic auditory processing or to a degraded phonological representation or both. We addressed this question examining an unselected sample of 10 children with SLI and 11 typically developing (TD) children, aged about 8 years, with respect to their basic auditory processing (duration and skewness discrimination) and phonological representation of prosodic (word stress) and segmental (consonant) contrasts. Our results show lower performance of the SLI group compared to the TD group in all tasks. Crucially, two subgroups of children with SLI emerged from our analyses: While one group was impaired in basic auditory perception, particularly affecting duration discrimination, the other showed no significant auditory processing deficits but a representational impairment.

Talker discrimination in preschool children with and without specific language impairment

Variability inherently present between multiple talkers can prove beneficial in the context of learning. However, the performance during learning paradigms by children with specific language impairment (SLI) remains below typically developing peers, even when multiple talkers are used. Preschool children with typically developing language (n = 17) and SLI (n = 17) participated in a talker discrimination task. Five different pairings of talkers (same male, different males, same female, different females, male + female) were used to present 50 spoken words. Children with SLI were significantly poorer in discriminating same and different male speakers compared to their typical peers. The present findings demonstrate that preschool children with SLI can experience difficulty distinguishing between talkers. Poor sensitivity to variation in talkers may contribute to poor learning in SLI for contexts where multiple talker input should benefit the learner.

LEARNING OUTCOMES

The reader will recognize that the presence of multiple talkers (voices) can assist or detract from performance on cognitive tasks. Children with specific language impairment are less proficient than their peers in distinguishing the same from different talkers.

Exemplar variability facilitates rapid learning of an otherwise unlearnable grammar by individuals with language-based learning disability

PURPOSE

Even without explicit instruction, learners are able to extract information about the form of a language simply by attending to input that reflects the underlying grammar. In this study, the authors explored the role of variability in this learning by asking whether varying the number of unique exemplars heard by the learner affects learning of an artificial syntactic form.

METHOD

Learners with normal language (n = 16) and language-based learning disability (LLD; n = 16) were exposed to strings of nonwords that represented an underlying grammar. Half of the learners heard 3 exemplars 16 times each (low variability group), and the other half of the learners heard 24 exemplars twice each (high variability group). Learners were then tested for recognition of items heard and generalization of the grammar with new nonword strings.

RESULTS

Only those learners with LLD who were in the high variability group were able to demonstrate generalization of the underlying grammar. For learners with normal language, both those in the high and the low variability groups showed generalization of the grammar, but relative effect sizes suggested a larger learning effect in the high variability group.

CONCLUSION

The results demonstrate that the structure of the learning context can determine the ability to generalize from specific training items to novel cases.

Using principles of learning to inform language therapy design for children with specific language impairment

BACKGROUND

Language treatment for children with specific language impairment (SLI) often takes months to achieve moderate results. Interventions often do not incorporate the principles that are known to affect learning in unimpaired learners.

AIMS

To outline some key findings about learning in typical populations and to suggest a model of how they might be applied to language treatment design as a catalyst for further research and discussion.

METHODS & PROCEDURES

Three main principles of implicit learning are reviewed: variability, complexity and sleep-dependent consolidation. After explaining these principles, evidence is provided as to how they influence learning tasks in unimpaired learners. Information is reviewed on principles of learning as they apply to impaired populations, current treatment designs are also reviewed that conform to the principles, and ways in which principles of learning might be incorporated into language treatment design are demonstrated.

MAIN CONTRIBUTION

This paper provides an outline for how theoretical knowledge might be applied to clinical practice in an effort to promote discussion.

CONCLUSIONS & IMPLICATIONS

Although the authors look forward to more specific details on how the principles of learning relate to impaired populations, there is ample evidence to suggest that these principles should be considered during treatment design.