Language in autism: domains, profiles and co-occurring conditions.

This article reviews the current knowledge state on pragmatic and structural language abilities in autism and their potential relation to extralinguistic abilities and autistic traits. The focus is on questions regarding autism language profiles with varying degrees of (selective) impairment and with respect to potential comorbidity of autism and language impairment: Is language impairment in autism the co-occurrence of two distinct conditions (comorbidity), a consequence of autism itself (no comorbidity), or one possible combination from a series of neurodevelopmental properties (dimensional approach)? As for language profiles in autism, three main groups are identified, namely, (i) verbal autistic individuals without structural language impairment, (ii) verbal autistic individuals with structural language impairment, and (iii) minimally verbal autistic individuals. However, this tripartite distinction hides enormous linguistic heterogeneity. Regarding the nature of language impairment in autism, there is currently no model of how language difficulties may interact with autism characteristics and with various extralinguistic cognitive abilities. Building such a model requires carefully designed explorations that address specific aspects of language and extralinguistic cognition. This should lead to a fundamental increase in our understanding of language impairment in autism, thereby paving the way for a substantial contribution to the question of how to best characterize neurodevelopmental disorders.

Identifying language impairment in bilingual children in France and in Germany.

BACKGROUND: The detection of specific language impairment (SLI) in children growing up bilingually presents particular challenges for clinicians. Non-word repetition (NWR) and sentence repetition (SR) tasks have proven to be the most accurate diagnostic tools for monolingual populations, raising the question of the extent of their usefulness in different bilingual populations. AIMS: To determine the diagnostic accuracy of NWR and SR tasks that incorporate phonological/syntactic complexity as discussed in recent linguistic theory. The tasks were developed as part of the Language Impairment Testing in Multilingual Settings (LITMUS) toolkit, in two different national settings, France and Germany, and investigated children with three different home languages: Arabic, Portuguese and Turkish. METHODS & PROCEDURES: NWR and SR tasks developed in parallel were administered to 151 bilingual children, aged 5;6-8;11, in France and in Germany, to 64 children in speech-language therapy (SLT) and to 87 children not in SLT, whose first language (L1) was Arabic, Portuguese or Turkish. Children were also administered standardized language tests in each of their languages to determine likely clinical status (typical development (TD) or SLI), and parents responded to a questionnaire including questions about early and current language use (bilingualism factors) and early language development (risk factors for SLI). Monolingual controls included 47 TD children and 29 children with SLI. Results were subjected to inter-group comparisons, to diagnostic accuracy calculation, and to correlation and multiple regression analyses. OUTCOMES & RESULTS: In accordance with previous studies, NWR and SR identified SLI in the monolingual children, yielding good to excellent diagnostic accuracy. Diagnostic accuracy in bilingual children was fair to good, generally distinguishing children likely to have SLI from children likely to have TD. Accuracy was necessarily linked to the determination of clinical status, which was based on standardized assessment in each of the child's languages. Positive early development, a composite risk factor for SLI, and not variables related to language exposure and use, generally emerged as the strongest predictor of performance on the two tasks, constituting additional, independent support for the efficacy of NWR and SR in identifying impairment in bilingual children. CONCLUSIONS & IMPLICATIONS: NWR and SR tasks informed by linguistic theory are appropriate for use as part of the diagnostic process for identifying language impairment in bilingual children for whom the language of assessment is different from the home language, in diverse sociolinguistic contexts.

Voice acoustics allow classifying autism spectrum disorder with high accuracy.

Early identification of children on the autism spectrum is crucial for early intervention with long-term positive effects on symptoms and skills. The need for improved objective autism detection tools is emphasized by the poor diagnostic power in current tools. Here, we aim to evaluate the classification performance of acoustic features of the voice in children with autism spectrum disorder (ASD) with respect to a heterogeneous control group (composed of neurotypical children, children with Developmental Language Disorder [DLD] and children with sensorineural hearing loss with Cochlear Implant [CI]). This retrospective diagnostic study was conducted at the Child Psychiatry Unit of Tours University Hospital (France). A total of 108 children, including 38 diagnosed with ASD (8.5 ± 0.25 years), 24 typically developing (TD; 8.2 ± 0.32 years) and 46 children with atypical development (DLD and CI; 7.9 ± 0.36 years) were enrolled in our studies. The acoustic properties of speech samples produced by children in the context of a nonword repetition task were measured. We used a Monte Carlo cross-validation with an ROC (Receiving Operator Characteristic) supervised k-Means clustering algorithm to develop a classification model that can differentially classify a child with an unknown disorder. We showed that voice acoustics classified autism diagnosis with an overall accuracy of 91% [CI95%, 90.40%-91.65%] against TD children, and of 85% [CI95%, 84.5%-86.6%] against an heterogenous group of non-autistic children. Accuracy reported here with multivariate analysis combined with Monte Carlo cross-validation is higher than in previous studies. Our findings demonstrate that easy-to-measure voice acoustic parameters could be used as a diagnostic aid tool, specific to ASD.

Does Phonological Complexity Provide a Good Index of Language Disorder in Children With Cochlear Implants?

Purpose Phonological complexity is known to be a good index of developmental language disorder (DLD) in normal-hearing children, who have major difficulties on some complex structures. Some deaf children with cochlear implants (CIs) present a profile that evokes DLD, with persistent linguistic difficulties despite good audiological and environmental conditions. However, teasing apart what is related to auditory deficit or to language disorder remains complex. Method We compared the performance of three groups of school-age children, 33 children with CI, 22 with DLD, and 24 with typical development, on a nonword repetition (NWR) task based on phonological complexity. Children with CI were studied regarding their linguistic profile, categorized in four subgroups ranging from excellent to very poor performance. Influence of syllable length and phonological structures on the results of all the children were explored. Results The NWR task correctly distinguished children with DLD from typically developing children, and also children with CI with the poorest linguistic performance from other children with CI. However, most complex phonological structures did not reliably identify children with CI displaying a profile similar to that of children with DLD because these structures were difficult for all of the children with CI. The simplest phonological structures were better at detecting persistent language difficulties in children with CI, as they were challenging only for the children with the poorest language outcomes. Conclusions The most complex phonological structures are not good indices of language disorder in children with CI. Phonological complexity represents a gradient of difficulty that affects normal-hearing and deaf children differently.

Brain responses to change in phonological structures of varying complexity in children and adults.

Language-related change-detection processes are often investigated using syllables that are very simple in terms of phonological structure. However, phonological complexity is known to be challenging for young typically developing children and pathological populations. We investigated brain correlates of phonological processing and their age-related changes with a passive change-detection protocol including stimuli of varying phonological complexity, which allowed comparing responses to simple and complex phonological deviancies. Mismatch Negativity (MMN) and Late Discriminative Negativity (LDN) responses were recorded in both school-age children (n = 22) and adults (n = 24). MMN was similar for simple and complex phonological deviancy in both groups, whereas LDN appeared to be modulated by phonological complexity, albeit with different patterns according to age. In response to complex phonological change, children displayed a larger LDN response with a typical fronto-central scalp distribution, while adults showed an additional right-posterior activity but no larger amplitude than for simple change. Thus, LDN appears to be a good electrophysiological index of phonological complexity processing. This study validated the use of the LDN through this protocol for the investigation of phonological complexity processing throughout the development.

A strategic plan to identify key neurophysiological mechanisms and brain circuits in autism.

Autism and Autism Spectrum Disorder (ASD) cover a large variety of clinical profiles which share two main dimensions: social and communication impairment and repetitive behaviors or restricted interests, which are present during childhood. There is now no doubt that genetic factors are a major component in the etiology of autism but precise physiopathological pathways are still being investigated. Furthermore, developmental trajectories combined with compensatory mechanisms will lead to various clinical and neurophysiological profiles which together constitute this Autism Spectrum Disorder. To better understand the pathophysiology of autism, comprehension of key neurophysiological mechanisms and brain circuits underlying the different bioclinical profiles is thus crucial. To achieve this goal we propose a strategy which investigates different levels of information processing from sensory perception to complex cognitive processing, taking into account the complexity of the stimulus and whether it is social or non-social in nature. In order to identify different developmental trajectories and to take into account compensatory mechanisms, we further propose that such protocols should be carried out in individuals from childhood to adulthood representing a wide variety of clinical forms.

Specific subtype of fluency disorder affecting French speaking children: A phonological analysis.

PURPOSE: Clinicians working with fluency disorders sometimes see children whose word repetitions are mostly located at the end of words and do not induce physical tension. Prior studies on the topic have proposed several names for these disfluencies including "end word repetitions", "final sound repetitions" and "atypical disfluency". The purpose of this study was to use phonological analysis to explore the patterns of this poorly recognized fluency disorder in order to better understand its specific speech characteristics. METHODS: We analyzed a spontaneous language sample of 8 French speaking children. Audio and video recordings allowed us to study general communication issues as well as linguistic and acoustical data. RESULTS: We did not detect speech rupture or coarticulation failures between the syllable onset and rhyme. The problem resides primarily on the rhyme production with a voicing interruption in the middle of the syllable nucleus or a repetition of the rhyme (nucleus alone or nucleus and coda), regardless of the position in the word or phrase. CONCLUSION: The present study provides data suggesting that there exist major differences in syllable production between the disfluencies produced by our 8 children and stuttered disfluencies. Consequently, we believe that this fluency disorder should be recognized as distinct from stuttering.