Family-Based Whole-Exome Analysis of Specific Language Impairment (SLI) Identifies Rare Variants in BUD13, a Component of the Retention and Splicing (RES) Complex

Specific language impairment (SLI) is a common neurodevelopmental disorder (NDD) that displays high heritability estimates. Genetic studies have identified several loci, but the molecular basis of SLI remains unclear. With the aim to better understand the genetic architecture of SLI, we performed whole-exome sequencing (WES) in a single family (ID: 489; n = 11). We identified co-segregating rare variants in three new genes: BUD13, APLP2, and NDRG2. To determine the significance of these genes in SLI, we Sanger sequenced all coding regions of each gene in unrelated individuals with SLI (n = 175). We observed 13 additional rare variants in 18 unrelated individuals. Variants in BUD13 reached genome-wide significance (p-value < 0.01) upon comparison with similar variants in the 1000 Genomes Project, providing gene level evidence that BUD13 is involved in SLI. Additionally, five BUD13 variants showed cohesive variant level evidence of likely pathogenicity. Bud13 is a component of the retention and splicing (RES) complex. Additional supportive evidence from studies of an animal model (loss-of-function mutations in BUD13 caused a profound neural phenotype) and individuals with an NDD phenotype (carrying a CNV spanning BUD13), indicates BUD13 could be a target for investigation of the neural basis of language.

Developmental Language Disorder and the Assessment of Spoken Language

Developmental language disorder (DLD), previously known as specific language impairment (SLI), is a long-term developmental disorder affecting approximately 7.5% of children. Language abilities in children with DLD are variable and can be challenging to ascertain with confidence. This chapter aims to discuss some of the challenges associated with assessing the language skills of children with DLD through an overview of different forms of language assessment including standardized language testing, language sample analysis, and observations. Uses and limitations of the different forms of assessment are considered, bearing in mind the different functions of assessment and the need to gain a full understanding of children’s profiles of strength and weakness and communicative functioning in context. The authors conclude with requirements for best practice in assessment and promising avenues of development in this area.

Phonological characteristics of novel gesture production in children with developmental language disorder: Longitudinal findings

Children with developmental language disorder (DLD; aka specific language impairment) are characterized based on deficits in language, especially morphosyntax, in the absence of other explanatory conditions. However, deficits in speech production, as well as fine and gross motor skill, have also been observed, implicating both the linguistic and motor systems. Situated at the intersection of these domains, and providing insight into both, is manual gesture. In the current work, we asked whether children with DLD showed phonological deficits in the production of novel gestures and whether gesture production at 4 years of age is related to language and motor outcomes two years later. Twenty-eight children (14 with DLD) participated in a two-year longitudinal novel gesture production study. At the first and final time points, language and fine motor skills were measured and gestures were analyzed for phonological feature accuracy, including handshape, path, and orientation. Results indicated that, while early deficits in phonological accuracy did not persist for children with DLD, all children struggled with orientation while handshape was the most accurate. Early handshape and orientation accuracy were also predictive of later language skill, but only for the children with DLD. Theoretical and clinical implications of these findings are discussed.

The Bouba-Kiki Effect in Children With Childhood Apraxia of Speech

Purpose: The bouba-kiki (BK) effect refers to associations between visual shapes and auditory pseudonames. Thus, when tested, people tend to associate the pseudowords bouba and kiki with round or spiky shapes, respectively. This association requires cross-modal sensory integration. The ability to integrate information from different sensory modalities is crucial for speech development. A clinical population that may be impaired in cross-modal sensory integration is children with childhood apraxia of speech (CAS). The purpose of this study was to examine the involvement of cross-modal sensory integration in children with (CAS). Method: The BK effect was assessed in participants with CAS ( n = 18) and two control groups: One control group was composed of children with developmental language disorder (DLD), also termed specific language impairment ( n = 15), and a second group included typically developing (TD) children ( n = 22). The children were presented with 14 pairs of novel visual displays and nonwords. All the children were asked to state which shape and nonword correspond to one another. In addition, background cognitive (Leiter-3) and language measures (Hebrew PLS-4) were determined for all children. Results: Children in the CAS group were less successful in associating between visual shapes and corresponding auditory pseudonames (e.g., associating the spoken word “bouba” with a round shape; the spoken word “kiki” with a spiky shape). Thus, children with CAS demonstrated a statistically significant reduced BK effect compared with participants with TD and participants with DLD. No significant difference was found between the TD group and the DLD group. Conclusions: The reduced BK effect in children with CAS supports the notion that cross-modal sensory integration may be altered in these children. Cross-modal sensory integration is the basis for speech production. Thus, difficulties in sensory integration may contribute to speech difficulties in CAS.

The comprehension of relative clauses in Mandarin Children with suspected specific language impairment

This paper investigates the comprehension of Relative Clauses (RCs) in 15 Mandarin children with suspected Specific Language Impairment (SLI) (aged between 4; 5 and 6; 0) and 29 typically developing (TD) controls. Results from a Character Picture Matching Task indicate that (i) the subject RC was better understood than the object RC in children with SLI, but there was no asymmetry in the comprehension of the two RCs in TD children; (ii) the performance of children with SLI was significantly worse than that of their TD peers; (iii) children with SLI were prone to committing thematic role reversal errors and middle errors. In order to overcome the shortcomings of previous accounts, we therefore put forward the Edge Feature Underspecification Hypothesis, which can not only explain the asymmetry of comprehension seen in children with SLI but also shed light on the nature of errors committed by them in the task.

Finiteness marking in Russian-speaking children with Specific Language Impairment

Much crosslinguistic acquisition research explores finiteness marking in typical development and Specific Language Impairment (SLI). Research into Russian, however, has focused on typical acquisition, not SLI. This article presents a first attempt to investigate finiteness marking in monolingual Russian-speaking children with SLI. We test two competing hypotheses: the Extended Optional Infinitive (EOI) hypothesis and the morphological richness account. The former predicts a large proportion of non-finite forms in the speech of children with SLI crosslinguistically. Due to the rich morphological verbal system of Russian, the latter hypothesis predicts that finiteness marking in Russian SLI will be relatively unimpeded, except for ‘near-miss’ errors. To test these predictions, we analyzed picture-story narrative samples collected from 67 monolingual Russian-acquiring children aged 4;1 to 4;11. All samples are part of the BiSLI corpus created by Tribushinina and colleagues and publicly available through the CHILDES project. We found that, similar to both aged-matched typically developing (TD) controls (N = 24) and younger TD children (N = 23), children with SLI (N = 20) are essentially adultlike in terms of finiteness marking of verbal forms in the matrix clause. The handful of errors observed in the SLI sample involved substitutions in only one inflectional category. These findings provide support for the morphological richness hypothesis over the EOI model of Russian SLI.

Pleiotropy between language impairment and broader behavioral disorders—an investigation of both common and rare genetic variants

Background Language plays a major role in human behavior. For this reason, neurodevelopmental and psychiatric disorders in which linguistic ability is impaired could have a big impact on the individual’s social interaction and general wellbeing. Such disorders tend to have a strong genetic component, but most past studies examined mostly the linguistic overlaps across these disorders; investigations into their genetic overlaps are limited. The aim of this study was to assess the potential genetic overlap between language impairment and broader behavioral disorders employing methods capturing both common and rare genetic variants. Methods We employ polygenic risk scores (PRS) trained on specific language impairment (SLI) to evaluate genetic overlap across several disorders in a large case-cohort sample comprising ~13,000 autism spectrum disorder (ASD) cases, including cases of childhood autism and Asperger’s syndrome, ~15,000 attention deficit/hyperactivity disorder (ADHD) cases, ~3000 schizophrenia cases, and ~21,000 population controls. We also examine rare variants in SLI/language-related genes in a subset of the sample that was exome-sequenced using the SKAT-O method. Results We find that there is little evidence for genetic overlap between SLI and ADHD, schizophrenia, and ASD, the latter being in line with results of linguistic analyses in past studies. However, we observe a small, significant genetic overlap between SLI and childhood autism specifically, which we do not observe for SLI and Asperger’s syndrome. Moreover, we observe that childhood autism cases have significantly higher SLI-trained PRS compared to Asperger’s syndrome cases; these results correspond well to the linguistic profiles of both disorders. Our rare variant analyses provide suggestive evidence of association for specific genes with ASD, childhood autism, and schizophrenia. Conclusions Our study provides, for the first time, to our knowledge, genetic evidence for ASD subtypes based on risk variants for language impairment.

Oral and Verbal Praxis in Impaired Language Learners

In the context of language descriptions, the terms oral and verbal praxis refer to volitional movements for performing oral gestures and movements for speech. These movements involve programming articulators and rapid sequences of muscle firings that are required for speech sound productions. A growing body of research has highlighted the links between oral motor kinematics and language production skills in both typically developing (TD) children and children with developmental language disorders, including Specific Language Impairment (SLI). Yet, there have been limited attempts to assess the link between non-linguistic and linguistic development. In the present study, we investigated oral and verbal praxis behaviors in children with SLI. Fifteen children with SLI formed a clinical group and 15 children with typical development who were matched to the clinical group for chronological age, gender, and socio-economic status formed the TD group. We assessed participants in both groups for their language abilities with age-appropriate standardized language tests. To investigate oral and verbal praxis behaviors, we administered the Assessment Protocol for Oral Motor, Oral Praxis and Verbal Praxis Skills to the two groups. We used the non-parametric Mann–Whitney U test to compare the two groups with respect to oral and verbal praxis measures; and we found a significant difference between isolated and sequential movements in the oral praxis section in two age subgroups of these groups ( p ≤ .05). Spearman’s correlations revealed a strong correlation between core language scores and sequential movements in the younger children with SLI and in TD children. These results showed co-morbidity between SLI and poor oral motor skills, suggesting that SLI is not just a language disorder, but a group of co-morbid conditions that include oral motor and verbal praxis difficulties.

Design and Evaluation of a Spanish Language Therapy Support System

Specific Language Impairment (SLI) is a language disorder that delays progress in mastering speech-language skills, and typically occurs in childhood. Most speech-language pathologists commonly use paper-based instruments to diagnose and treat this problem. This article describes the design, implementation, and evaluation of SATEL, an ontology-based system used both in diagnosing this condition and as part of speech therapy for children with SLI. With the help of a Kinect sensor, SATEL is able to recognize and classify pronounced words. The proposed system was designed and evaluated by a team of four speech-language pathologists and 26 children diagnosed with SLI. Results showed an accuracy rate of 94.42% and 97.75% in recognizing syllables and words correctly and incorrectly pronounced in the diagnostic and treatment modules, respectively.