Processing Speed Measures as Clinical Markers for Children With Language Impairment

Language Skills in Children with Attention Deficit Hyperactivity Disorder and Developmental Language Disorder: A Systematic Review

(1) Background: Attention Deficit Hyperactivity Disorder (ADHD) and Developmental Language Disorder (DLD) are neurodevelopmental disorders that affect various areas of children's development, such as language. It exists an emerging idea that ADHD is characterised by the presence of language difficulties, which can be explained by the high comorbidity between ADHD and DLD. The aim of this review is to analyse the empirical evidence of language competence in children aged 6-17 years old, diagnosed with ADHD and/or DLD. (2) Method: Fifteen studies with experimental designs were identified from Scopus, PsycINFO, and WoS databases, reporting on language skills in children diagnosed with ADHD and/or DLD. Studies relating executive functioning to language skills in this target population were also included. (3) Results: The literature is heterogeneous and different components of language are also examined. Even though the results are contradictory, they convincingly demonstrate there are overlapping symptoms between ADHD and DLD, such as language skills and executive functions. (4) Conclusions: The differences in the samples limit the generalisability of the results. Therefore, this review highlights the importance of considering language skills when designing individualised interventions for the population with ADHD and DLD, both in comorbidity and in isolation.

Cognitive predictors of language abilities in primary school children: A cascaded developmental view

This study investigated the longitudinal relationship between children's domain-general cognitive constraints underlying phonological and sentence processing development in a big sample of typically developing children. 104 children were tested on non-linguistic processing speed, phonological skills (phonological short term memory, phonological knowledge, phonological working memory), and sentence processing abilities (sentence repetition and receptive grammar) in 1^st grade (aged 6 to 6.5) and one year later. A cross-lagged structural equation model showed that non-linguistic processing speed was a concurrent predictor of phonological skills, and that phonology had a powerful effect on the child's sentence processing abilities concurrently and longitudinally, providing clear evidence for the role of domain-general processes in the developmental pathway of language. These findings support a cascaded cognitive view of language development and pose important challenges for evaluation and intervention strategies in childhood.

The significance of nonverbal performance in children with developmental language disorder

Nonverbal deficits are frequently reported in children with developmental language disorder (DLD). In the new diagnostic criteria of DLD, the previous requirement of normal nonverbal performance has been removed and children with below average and even weak nonverbal skills now fit under the DLD definition. However, the significance of the nonverbal cognitive level, and the connection between nonverbal and verbal skills in these children diagnosed according to the new DLD classification is unclear. In the present study, the significance of nonverbal cognitive level on verbal performance was investigated among preschool-aged children with remarkable deficits in language development. Verbal skills were compared between average, below average, and weak nonverbal cognitive level groups. The connection between nonverbal and verbal skills was evaluated with Pearson correlations, and the covariance structure of the subtests used was modeled with Structural Modelling. The connection between nonverbal cognitive level and verbal skills was clear; weaker nonverbal cognitive levels were associated with lower verbal skills. While receptive language skills and verbal short-term-memory (STM) were the most profound weaknesses, relative strengths emerged for each nonverbal cognitive level group in fluid intelligence, especially in nonverbal reasoning tasks without time limits. In addition, fluid intelligence was strongly linked to verbal understanding and reasoning. These results suggest that the relative strength in nonverbal fluid intelligence with specific weaknesses in receptive language, verbal understanding, and verbal STM could be used as basic factors differentiating children with DLD from those with intellectual disability.

Developmental Language Disorder Is Associated With Slower Processing Across Domains: A Meta-Analysis of Time-Based Tasks

PURPOSE

Individuals with developmental language disorder (DLD) often exhibit slower processing on time-based tasks in comparison with age-matched peers. Processing speed has been linked to various linguistic skills and might serve as a global indicator of individual differences in language abilities. Despite an extensive literature on processing speed in DLD, it remains unclear whether slower processing is domain general or restricted to linguistic and/or auditory tasks.

METHOD

This meta-analysis used robust variance estimation to compare response/reaction times (RTs) of DLD and age-matched groups (N = 812 DLD, 870 neurotypical; M _age [DLD] = 8.9 years, range: 4.3-22.7 years). Moderators included task (simple RT, choice RT, naming, congruent/baseline conditions of interference control tasks), stimulus type (linguistic/nonlinguistic), stimulus modality (auditory/nonauditory), and response modality (verbal/nonverbal). Age and publication year were covariates.

RESULTS

The overall effect based on 46 studies and 144 estimates indicated longer mean RTs in DLD groups (g = .47, p < .001, 95% CI [.38, .55]). Moderator analyses indicated larger effects when tasks required verbal as opposed to nonverbal responses. No other moderators approached significance. All subgroup analyses were significant, indicating longer mean RTs in DLD groups across tasks, stimulus types, stimulus modalities, and response modalities.

CONCLUSIONS

Individuals with DLD exhibit longer RTs across verbal and nonverbal tasks, which may contribute to observed difficulties in language, motor skills, and executive functioning. Simple processing speed measures should be included in screening for language delays but may not be suitable for differential diagnosis, given that slower processing may occur across multiple disorders.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.21809355.

A preliminary epidemiologic study of social (pragmatic) communication disorder in the context of developmental language disorder

BACKGROUND

There is extremely limited population-based research on social (pragmatic) communication disorder (SCD). Population-based samples have the potential to better characterize the SCD phenotype by mitigating confounds and biases that are typical of convenience and clinical samples.

AIMS

The aims of this preliminary epidemiologic study were to advance our understanding of the SCD phenotype relative to developmental language disorder (DLD), obtain an estimate of prevalence, identify risk factors and lay the groundwork for future population level research of SCD.

METHODS & PROCEDURES

We analysed existing data from the EpiSLI Database to examine social communication skills in 393 8th grade (13-14 years) children with and without a history of DLD. The primary measure used to evaluate SCD was the Children's Communication Checklist (CCC-2). Two case definitions of SCD reflecting DSM-5 criteria were examined. Both definitions involved significant pragmatic impairment, employing a commonly adopted clinical cut-point of 1.5 SD. In one case, pragmatic deficits could occur along with structural language deficits and, in the other case (established using principal component analysis), pragmatic and social skills were disproportionately lower than structural language abilities.

OUTCOMES & RESULTS

When using the first case definition, SCD was much more common in children with a history of DLD than without DLD and history of language disorder at kindergarten was a significant risk factor for SCD in adolescence. However, it is important to note that SCD could be found in children with no prior deficits in other aspects of language. When the second definition was employed, SCD was equally distributed across children with and without a history of DLD. Male sex was a significant risk factor using this case definition of SCD. The estimated prevalence of SCD ranged from 7% (SE = 1.5%) to 11% (SE = 1.7%), acknowledging that prevalence depends on the cut-point selected to determine communication disorder.

CONCLUSIONS & IMPLICATIONS

These findings contribute to our understanding of the association between SCD and DLD by recognizing varying profiles of pragmatic and social communication difficulties, which in turn may help refine our diagnostic categories. Preliminary prevalence estimates of SCD can serve as an initial guidepost for identification and planning for intervention services for this condition.

WHAT THIS PAPER ADDS

What is already known on this subject There is considerable debate about the diagnostic category of SCD and its relation to other neurodevelopmental disorders. What this study adds to existing knowledge Using data from a US-based epidemiologic sample of DLD, this study offers new information about the association between SCD and DLD, provides preliminary estimates of SCD prevalence, and identifies risk factors for SCD. Clinical implications of this study Improved understanding of possible profiles of pragmatic and social communication deficits will help to clarify diagnostic categories and preliminary prevalence estimates may assist with ensuring availability of adequate intervention services.

Structure of Cognitive Functions in Monolingual Preschool Children With Typical Development and Children With Developmental Language Disorder

Purpose Developmental language disorder (DLD) is defined by persistent difficulties with language, but a growing body of evidence suggests that it is also associated with domain-general and nonverbal information-processing deficits. However, the interconnections between cognitive functions, both nonverbal and language related, are still unclear. With the aim of gaining more comprehensive insight into the cognitive deficits related to DLD, we investigated and compared the cognitive structure of children with DLD and typically developing (TD) children. Method As a part of the Helsinki longitudinal SLI study, monolingual Finnish preschoolers (N = 154; TD group: n = 66, DLD group: n = 88) were assessed with 23 tasks measuring nonverbal and verbal reasoning, language processing, memory, visuomotor functions, attention, and social cognition. Exploratory factor analysis and structural equation modeling were performed to examine latent constructs and to test measurement invariance between the TD and DLD groups. Results Measurement invariance was not found across the TD and DLD groups. Best fitting structure for TD children included factors reflecting verbal abilities, processing speed/short-term memory, visuomotor functions, and visuoconstructive abilities/nonverbal reasoning. The DLD group's structure comprised nonverbal abilities, naming/expressive language, verbal comprehension, and verbal/declarative memory. Conclusions The findings suggest that the structure of cognitive functions differs in TD children and children with DLD already at preschool age. Nonverbal functions seem more unified, whereas verbal functions seem more varying in preschoolers with DLD compared to TD children. The results can be used in future research for prognosis of DLD and planning interventions.

Non-linguistic cognitive measures as predictors of functionally defined developmental language disorder in monolingual and bilingual children

BACKGROUND & AIMS

Given that standardized language measures alone are inadequate for identifying functionally defined developmental language disorder (fDLD), this study investigated whether non-linguistic cognitive abilities (procedural learning, motor functions, executive attention, processing speed) can increase the prediction accuracy of fDLD in children in linguistically diverse settings.

METHODS & PROCEDURES

We examined non-linguistic cognitive abilities in mono- and bilingual school-aged children (ages 8-12) with and without fDLD. Typically developing (TD) children (14 monolinguals, 12 bilinguals) and children with fDLD (28 monolinguals, 12 bilinguals) completed tasks measuring motor functions, procedural learning, executive attention and processing speed. Children were assigned as fDLD based on parental or professional concerns regarding children's daily language functioning. If no concerns were present, children were assigned as TD. Standardized English scores, non-verbal IQ scores and years of maternal education were also obtained. Likelihood ratios were used to examine how well each measure separated the fDLD versus TD groups. A binary logistic regression was used to test whether combined measures enhanced the prediction of identifying fDLD status.

OUTCOMES & RESULTS

A combination of linguistic and non-linguistic measures provided the best distinction between fDLD and TD for both mono- and bilingual groups. For monolingual children, the combined measures include English language scores, functional motor abilities and processing speed, whereas for bilinguals, the combined measures include English language scores and procedural learning.

CONCLUSIONS & IMPLICATIONS

A combination of non-linguistic and linguistic measures significantly improved the distinction between fDLD and TD for both mono- and bilingual groups. This study supports the possibility of using non-linguistic cognitive measures to identify fDLD in linguistically diverse settings.

WHAT THIS PAPER ADDS

What is already known on the subject Given that standardized English language measures may fail to identify functional language disorder, we examined whether supplementing English language measures with non-linguistic cognitive tasks could resolve the problem. Our study is based on the hypothesis that non-linguistic cognitive abilities contribute to language processing and learning. This is further supported by previous findings that children with language disorder exhibit non-linguistic cognitive deficits. What this paper adds to existing knowledge The results indicated that a combination of linguistic and non-linguistic cognitive abilities increased the prediction of functional language disorder in both mono- and bilingual children. What are the potential or actual clinical implications of this work? This study supports the possibility of using non-linguistic cognitive measures to identify the risk of language disorder in linguistically diverse settings.

Contribution of Nonverbal Cognitive Skills on Bilingual Children’s Grammatical Performance: Influence of Exposure, Task Type, and Language of Assessment

This study explores the contribution of nonverbal working memory and processing speed on bilingual children’s morphosyntactic knowledge, after controlling for language exposure. Participants include 307 Spanish–English bilinguals in Kindergarten, second, and fourth grade (mean age = 7;8, SD = 18 months). Morphosyntactic knowledge in English and Spanish was measured using two separate language tasks: a cloze task and a narrative language task. In a series of four hierarchical linear regressions predicting cloze and narrative performance in English and Spanish, we evaluate the proportion of variance explained after adding (a) English exposure, (b) processing speed and working memory, and (c) interaction terms to the model. The results reveal the differential contribution of nonverbal cognitive skills across English and Spanish. Cognition was not significantly related to performance on either grammatical cloze or narrative tasks in Spanish. Narrative tasks in English were significantly predicted by processing speed, after controlling for age and exposure. Grammatical cloze tasks in English posed an additional cognitive demand on working memory. The findings suggest that cognitive demands vary for bilinguals based on the language of assessment and the task.

Identifying Bilingual Children at Risk for Language Impairment: The Implication of Children's Response Speed in Narrative Contexts

The purpose of the study was to examine whether monolingual adults can identify the bilingual children with LI on the basis of children’s response speed to the examiner. Participants were 37 monolingual English-speaking young adults. Stimuli were 48 audio clips from six sequential bilingual children (48 months) who were predominately exposed to Cantonese (L1) at home from birth and started to learn English (L2) in preschool settings. The audio clips for each child were selected from an interactive story-retell task in both Cantonese and English. Three of the children were typically developing, and three were identified as having a language impairment. The monolingual adult participants were asked to judge children’s response times for each clip. Interrater reliability was high (Kalpha = 0.82 for L1; Kalpha = 0.75 for L2). Logistic regression and receiver operating characteristic curves were used to examine the diagnostic accuracy of the task. Results showed that monolingual participants were able to identify bilingual children with LI based on children’s response speed. Sensitivity and specificity were higher in Cantonese conditions compared to English conditions. The results added to the literature that children’s response speed can potentially be used, along with other measures, to identify bilingual children who are at risk for language impairment.

Neural patterns elicited by sentence processing uniquely characterize typical development, SLI recovery, and SLI persistence

Background

A substantial amount of work has examined language abilities in young children with specific language impairment (SLI); however, our understanding of the developmental trajectory of language impairment is limited. Along with studying the behavioral changes that occur across development, it is important to examine the neural indices of language processing for children with different language trajectories. The current study sought to examine behavioral and neural bases of language processing in adolescents showing three different trajectories: those with normal language development (NL), those exhibiting persistent SLI (SLI-Persistent), and those with a history of SLI who appear to have recovered (SLI-Recovered).

Methods

Through a sentence judgment task, we examined semantic and syntactic processing. Adolescents judged whether or not each sentence was semantically and syntactically correct. Stimuli consisted of naturally spoken sentences that were either correct, contained a semantic verb error, or contained a syntactic verb agreement error. Verb agreement errors consisted of omission and commission violations of the third-person singular -s. Behavioral button-press responses and electroencephalographic recordings were collected. Behavioral judgments and mean amplitude of the N400 and P600 components were examined.

Results

Adolescents in the SLI-Persistent group had lower sentence judgment accuracy overall, relative to the NL and SLI-Recovered groups. Accuracy in judging omission and commission syntactic errors were marginally different, with marginally lower accuracy for commission errors. All groups demonstrated an N400 component elicited by semantic violations. However, adolescents in the SLI-Persistent group demonstrated a less robust P600 component for syntactic violations. Furthermore, adolescents in the SLI-Recovered group exhibited a similar neural profile to the NL group for the semantic and syntactic omission violations. However, a unique profile with initial negativity was observed in the SLI-Recovered group in the commission violation condition.

Conclusions

Adolescents with persistent language impairment continue to demonstrate delays in language processing at the behavioral and neural levels. Conversely, the adolescents in the SLI-Recovered group appear to have made gains in language processing skills to overcome their initial impairments. However, our findings suggest that the adolescents in the SLI-Recovered group may have compensatory processing strategies for some aspects of language, as evidenced by a unique event-related potential profile.

From Sensory Perception to Lexical-Semantic Processing: An ERP Study in Non-Verbal Children with Autism

This study examines electrocortical activity associated with visual and auditory sensory perception and lexical-semantic processing in nonverbal (NV) or minimally-verbal (MV) children with Autism Spectrum Disorder (ASD). Currently, there is no agreement on whether these children comprehend incoming linguistic information and whether their perception is comparable to that of typically developing children. Event-related potentials (ERPs) of 10 NV/MV children with ASD and 10 neurotypical children were recorded during a picture-word matching paradigm. Atypical ERP responses were evident at all levels of processing in children with ASD. Basic perceptual processing was delayed in both visual and auditory domains but overall was similar in amplitude to typically-developing children. However, significant differences between groups were found at the lexical-semantic level, suggesting more atypical higher-order processes. The results suggest that although basic perception is relatively preserved in NV/MV children with ASD, higher levels of processing, including lexical- semantic functions, are impaired. The use of passive ERP paradigms that do not require active participant response shows significant potential for assessment of non-compliant populations such as NV/MV children with ASD.