Non-word repetition impairment in autism and specific language impairment: evidence for distinct underlying cognitive causes

Language phenotypes in children with autism spectrum disorder, expressive language disorder, and typical language development

The aim of this study was to compare language abilities in 4-6-year-old Georgian-speaking children with typical language development (TLD), expressive language disorder (ELD), and autism spectrum disorder (ASD). Language linguistic components, such as phonology, semantics, syntax, morphology, and pragmatics, were examined along with verbal behavior types like "mand," "tact," "echoic," and "intraverbal." Our sample comprised 148 children, with a gender distribution of 50 girls and 98 boys. Significant differences were observed in the application of various parts of speech across the three groups. Children with ELD were found to use pronouns more frequently compared to TLD and ASD groups. Conversely, children exhibiting typical language development displayed a greater usage of conjunctions and particles than the other groups. Notably, linguistic error patterns varied across groups: children with ELD predominantly committed errors in phonetics and morphosyntax, while children with ASD had more pragmatic errors and also struggled with morphosyntax. Moreover, the ASD group was found to use "mands" and "echoics" more frequently than both the TLD and ELD groups.

Facing phonological complexity as an autistic adult: An exploratory study

Background and aims

While it has been suggested that phonology is relatively spared in autism, some studies have shown that many autistic children and adolescents exhibit severe phonological impairment, of which syllabic complexity is a reliable index. However, although autism is a lifelong disorder, no such evidence exists for adults. The aim of the present study is to bridge this knowledge gap by investigating how autistic adults deal with phonological complexity.

Method

Phonological abilities were assessed in 48 autistic adults aged 18 to 56 years and 50 controls matched on age and sex/gender. A linguistically motivated Nonword Repetition (NWR) task manipulating syllabic complexity, LITMUS-QU(Quasi Universal)-FR(ench)-NWR-Adults, was used to distinguish participants with and without a phonological impairment. In addition to the NWR task, additional tests were conducted to examine potential factors influencing phonological performance. These measures included morphosyntax, vocabulary, nonverbal IQ (NVIQ), short-term memory, working memory, and autism severity, providing a comprehensive understanding of variables affecting phonological abilities in autistic adults.

Results

Global performance on NWR was significantly lower and spanned a wider range in the autism group than that in the control group. By looking at individual results across the structures and substructures included in NWR, which presented varying degrees of syllabic complexity, it was possible to uncover great variability among autistic individuals with a phonologicalimpairment. Phonological proficiency appeared to be related to morphosyntax rather than to lexical knowledge and nonverbal cognition, including memory. Moreover, phonological skills did not correlate with autism severity.

Conclusions

This study represents a first step towards understanding how to characterize phonological skills in autistic adults. Our findings indicate that syllabic complexity prompts diverse behaviors among autistic individuals with impaired phonology. Further research is required to gain insight into the cause(s) underlying the detected difficulties.

Neural Processing of Speech Sounds in Autistic Kindergarteners as a Predictor of Reading Outcomes

Phonology is an important foundation of reading development; however, little is known about the neural substrates of speech sound processing and reading development in autistic children. We investigated early auditory event-related potentials (ERPs) in response to speech sounds and their association with reading ability (word recognition and reading comprehension). 56 kindergarteners (28 ASD, 28 TD) completed an ERP task using rhyming, bisyllabic pseudowords (/gibu/ and /bidu/) in an old/new design: 50% "old" and 50% "new" stimuli presented following a sensitization block of 100% "old" stimuli. Behavioral measures of reading ability were completed at kindergarten entry and exit. Results from generalized linear mixed models revealed a significant three-way interaction between stimuli ("new" vs. "old"), diagnosis (ASD vs. TD), and reading ability (for word recognition and reading comprehension) for P1 and P2 amplitude. Follow-up analyses revealed that autistic children with lower reading abilities showed greater P1 and P2 amplitudes for "new" vs. "old" stimuli, with effects ranging from marginal to significant (p's 0.04-0.07). Regression analyses revealed that old/new ERP difference scores significantly predicted later word recognition at kindergarten year-end (P1 amplitude: p = .05; P2 amplitude: p = .04), but not reading comprehension, controlling for sex and nonverbal IQ. Autistic children with poorer reading skills, specifically those with weaker word recognition abilities, show neural differences when processing speech sounds compared to autistic peers with greater reading ability and typically developing children. A better understanding of the neural basis of speech sound processing could enhance our insight into the heterogeneity in reading among individuals with ASD and guide future treatment approaches.

Non-Word Repetition in Arabic-speaking children with and without Autism Spectrum Disorder (ASD): A closer look into accuracy and error patterns

Non-Word Repetition (NWR) tasks effectively identify language impairments and assess phonological skills across diverse populations and languages, including Arabic. Prior research revealed heterogeneity of performance in children with Autism Spectrum Disorder (ASD) on NWR tasks. The current study is the first to evaluate phonological skills of Palestinian-Arabic-speaking children with and without ASD, employing a Palestinian-Arabic NWR task. A total of 142 Palestinian-Arabic-speaking children, aged 5-11 participated in the study, including 75 children with Typical Language Development (TLD) and 67 children with ASD. The NWR task included 18 non-words of varying length (1-4 syllables) and complexity (with and without consonant clusters). Quantitative analysis examined the effects of length and phonological complexity on the NWR accuracy scores in children with TLD and ASD. Error pattern analysis accounting for phoneme and syllable substitutions/deletions/additions and lexicalisations aimed to shed light on the phonological representations of children with and without ASD. Within the ASD group, two subgroups emerged: 72% exhibited age-appropriate NWR performance, while 28% showed performance at-risk for phonological impairment. Non-word length, rather than complexity, significantly influenced the children's performance. Consonant substitution was the most frequent error pattern across all groups. On the theoretical side, these findings extend cross-linguistic evidence of phonological skill heterogeneity in children with ASD to Arabic-speaking children. Additionally, they highlight an overall delayed but qualitatively similar pattern of phonological development in children with ASD. On the clinical side, results underscore the importance of comprehensive language assessment in children with ASD.

Non-word repetition and vocabulary in Kuwaiti Arabic-speaking children with down syndrome and typically developing children

OVERVIEW

Non-word repetition (NWR) is one of the most effective predictors of language impairments in children as it has been found to correlate with various language measures and the association between NWR and vocabulary is well documented in typically developing (TD) studies. However, there is a dire need for investigations of language skills in Kuwaiti Arabic individuals with Down Syndrome, and this study set out to fill a gap in this field.

METHOD

In this paper, we compare the vocabulary and NWR skills of a group of 48 individuals with DS aged 6-20 years to a group of 44 TD children aged 3-10 years matched on nonverbal IQ. Furthermore, we investigate the correlations among these language measures in the two groups and examine whether NWR can predict receptive and expressive vocabulary in these two groups.

RESULT

Results found DS participants performed significantly less than the TD group on the three language measures (receptive vocabulary t(90)= -3.17, p < .01, expressive vocabulary t(90)= -3.27, p < .01, and NWR t(90)= -8.32, p < .01). Moreover, there were strong correlations between NWR and vocabulary (receptive and expressive) in the TD group but not the DS group.

CONCLUSION

Findings supported the working memory model and the phonological processing account for the TD group. On the other hand, the poor association between NWR and vocabulary in the DS group might be due to poor phonological discrimination difficulties and speech discrimination difficulties.

Specificity of phonological representations in school-age high-functioning ASD children

PURPOSE

Well-specified phonological representations are important for the development of spoken and written language. This study investigates the types of speech errors and the quality of phonological representations in Greek-speaking school-age children with high-functioning autism spectrum disorder (HF-ASD), as well as the relationship between stored phonological representations and speech output in this sample, according to Stackhouse and Wells' (1997) model.

METHOD

All participants completed a phonological and a naming test, and a non-word repetition task. A receptive phonological task was administered to a subgroup of HF-ASD and typically developing (TD) participants. According to performance in the phonological test, the HF-ASD children were categorised as ASD with Speech Sound Disorder (SSD) or ASD without SSD.

RESULT

The HF-ASD children made significantly more speech errors and showed significant difficulties in the repetition of non-words and the stored phonological representations compared to the TD group but had the same naming abilities with their TD peers. The ASD children with SSD and without SSD performed alike in the receptive task, indicating that both groups had unspecified phonological representations.

CONCLUSION

These results support the hypothesis of distinct phonological representations for speech input and output and highlight the need of using receptive tasks to evaluate underlying phonological knowledge, a process which could allow clinicians to identify the level of speech breakdown.

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.

Altered engagement of the speech motor network is associated with reduced phonological working memory in autism

Nonword repetition, a common clinical measure of phonological working memory, involves component processes of speech perception, working memory, and speech production. Autistic children often show behavioral challenges in nonword repetition, as do many individuals with communication disorders. It is unknown which subprocesses of phonological working memory are vulnerable in autistic individuals, and whether the same brain processes underlie the transdiagnostic difficulty with nonword repetition. We used functional magnetic resonance imaging (fMRI) to investigate the brain bases for nonword repetition challenges in autism. We compared activation during nonword repetition in functional brain networks subserving speech perception, working memory, and speech production between neurotypical and autistic children. Autistic children performed worse than neurotypical children on nonword repetition and had reduced activation in response to increasing phonological working memory load in the supplementary motor area. Multivoxel pattern analysis within the speech production network classified shorter vs longer nonword-repetition trials less accurately for autistic than neurotypical children. These speech production motor-specific differences were not observed in a group of children with reading disability who had similarly reduced nonword repetition behavior. These findings suggest that atypical function in speech production brain regions may contribute to nonword repetition difficulties in autism.

Comparing Early Pragmatics in Typically Developing Children and Children with Neurodevelopmental Disorders

This study examined the early pragmatic language skills in typically developing (TD) preschool-age children, children with language impairment (LI) and children with autism spectrum disorder (ASD). Two hundred and sixty-two TD children, 73 children with LI, and 16 children with ASD were compared on early pragmatics through direct assessment (DA). Post hoc analysis revealed that children in two clinical groups displayed significant pragmatic language deficits. Children in the ASD group who were older exhibited comparable degree of impairments as their LI peers, suggesting a relatively stagnant development of pragmatic language skills in children with ASD. Findings also supported the use of DA in identifying pragmatic language deficits, which have implications for the adoption of this assessment approach in clinical settings.

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.

Developmental Language Disorder and Autism: Commonalities and Differences on Language

Language and communication deficits characterize both autism spectrum disorder and developmental language disorder, and the possibility of there being a common profile of these is a matter of tireless debate in the research community. This experimental study addresses the relation of these two developmental conditions in the critical topic of language. Α total of 103 children (79 males, 24 females) participated in the present study. Specifically, the study's sample consisted of 40 children with autism, 28 children with developmental language disorder, and 35 typically developing children between 6 and 12 years old. All children completed language and cognitive measures. The results showed that there is a subgroup inside the autism group of children who demonstrate language difficulties similar to children with developmental language disorder. Specifically, two different subgroups were derived from the autism group; those with language impairment and those without. Both autism and language-impaired groups scored lower than typically developing children on all language measures indicating a common pathology in language ability. The results of this study shed light on the relation between the two disorders, supporting the assumption of a subgroup with language impairment inside the autism spectrum disorder population. The common picture presented by the two developmental conditions highlights the need for further research in the field.

Language Abilities of Russian Primary-School-Aged Children with Autism Spectrum Disorder: Evidence from Comprehensive Assessment

The purpose of the present research was to comprehensively assess the language abilities of Russian primary-school-aged children with Autism Spectrum Disorder (ASD), varying in non-verbal IQ, at all linguistic levels (phonology, lexicon, morphosyntax, and discourse) in production and comprehension. Yet, the influence of such non-language factors as children's age, the severity of autistic traits, and non-verbal IQ on language functioning was studied. Our results indicate a high variability of language skills in children with ASD (from normal to impaired) which is in line with the previous studies. Interestingly, the number of children with normal language abilities was related to the linguistic levels: according to more complex morphosyntax and discourse tests, fewer children with ASD were within the normal range unlike the results in simpler phonological and lexical tests. Importantly, we found that language abilities were best predicted by non-verbal IQ but were independent from age and the severity of autistic traits. The findings support the claim that formal language assessment of children with ASD needs to include all linguistic levels, from phonology to discourse, for helping speech-language therapists to choose an appropriate therapy target.

Eye-Tracking Reveals Absent Repetition Learning Across the Autism Spectrum: Evidence From a Passive Viewing Task

In the domain of memory, autism is characterized by difficulties in explicitly remembering the specific order of stimuli, whereas implicit serial order memory appears to be preserved. This pattern is of considerable interest because serial order memory is known to play a critical role in children's language development. Currently, however, few paradigms exist that can effectively probe serial order memory across heterogeneous groups of children, including those who are minimally verbal. We present two experiments, involving 39 adults (20 ASD; 19 TD) and 130 children (86 ASD; 44 TD), that address this issue using an eye-tracking paradigm, which simply required participants to "watch out for a bunny" that appeared in repeating sequences of screen locations. The adults in Experiment 1 all had normative IQs, whereas Experiment 2 included children with and without substantial language and intellectual difficulties. In both experiments gaze latencies and anticipatory fixations to the bunny indicated reliable repetition learning effects in the TD but not the ASD groups. Importantly, we were able to acquire reliable data from around half of the children with significant language impairments in Experiment 2, indicating that the paradigm can shed light on important learning processes in this underrepresented group. We discuss the implications of these findings for theories of memory in ASD as well as for the utility of eye-tracking technology to probe repetition learning effects in autism. Autism Res 2020, 13: 1929-1946. © 2020 The Authors. Autism Research published by International Society for Autism Research and Wiley Periodicals LLC. LAY SUMMARY: Remembering the specific order of stimuli plays an important role in language development and is thought to be a source of difficulty for autistic individuals. Research in this area, however, rarely includes autistic participants who are minimally verbal. Here we develop an eye-tracking paradigm that demonstrates serial order learning difficulties across the autism spectrum. We discuss the implications of these findings for our understanding of the role of memory difficulties in the varied language profiles across the autism spectrum.

Associations and Dissociations among Phonological Processing Skills, Language Skills and Nonverbal Cognition in Individuals with Autism Spectrum Disorder

AIMS

The purpose of this study was to examine the nature of phonological processing in individuals with autism spectrum disorder (ASD) as it pertains to their nonverbal cognitive and linguistic abilities.

METHODS

Twenty-one participants between the ages of 9 and 21 years were administered a nonverbal cognitive assessment (Raven test), a language measure that requires receptive and expressive knowledge of semantics, syntax and morphology, as well as the integration across these language domains (CELF-4), and a measure of phonological processing (CTOPP).

RESULTS

Results show that performance on nonword repetition (NWR) that reflects an aspect of phonological memory was significantly low, whereas performance on phoneme reversal, phoneme elision, blending words and memory for digits was within the normal range. Hierarchical regressions with age, nonverbal intelligence (Raven test) and receptive language (CELF) as predictors showed that for NWR and phoneme elision the receptive part of the CELF was the main significant -predictor, after controlling for age. For phoneme reversal and memory for digits, however, the Raven score was the significant predictor, suggesting that cognitive nonverbal ability is the main factor explaining variability in these tasks.

CONCLUSIONS

A deficit in phonological memory characterizes individuals in the autistic population. This deficit may influence language acquisition in this population consistent with other populations of children with language impairments. Other tasks of phonological awareness, however, might be preserved especially when they do not involve memory for long phonological sequences and when the cognitive abilities are within the norm.

Talker Processing in Mandarin-Speaking Congenital Amusics

Purpose The ability to recognize individuals from their vocalizations is an important trait of human beings. In the current study, we aimed to examine how congenital amusia, an inborn pitch-processing disorder, affects discrimination and identification of talkers' voices. Method Twenty Mandarin-speaking amusics and 20 controls were tested on talker discrimination and identification in four types of contexts that varied in the degree of language familiarity: Mandarin real words, Mandarin pseudowords, Arabic words, and reversed Mandarin speech. Results The language familiarity effect was more evident in the talker identification task than the discrimination task for both participant groups, and talker identification accuracy decreased as native phonological representations were removed from the stimuli. Importantly, amusics demonstrated degraded performance in both native speech conditions that contained phonological/linguistic information to facilitate talker identification and nonnative conditions where talker voice processing primarily relied on phonetics cues, including pitch. Moreover, the performance in talker processing can be predicted by the participants' musical ability and phonological memory capacity. Conclusions The results provided a first set of behavioral evidence that individuals with amusia are impaired in the ability of human voice identification. Meanwhile, it is found that amusia is not only a pitch disorder but is likely to affect the phonological processing of speech, in terms of using phonological information in native speech to analyze a talker's identity. The above findings expanded the understanding of the nature and scope of congenital amusia. Supplemental Material https://doi.org/10.23641/asha.12170379.

Language deficits in specific language impairment, attention deficit/hyperactivity disorder, and autism spectrum disorder: An analysis of polygenic risk

Language is one of the cognitive domains often impaired across many neurodevelopmental disorders. While for some disorders the linguistic deficit is the primary impairment (e.g., specific language impairment, SLI), for others it may accompany broader behavioral problems (e.g., autism). The precise nature of this phenotypic overlap has been the subject of debate. Moreover, several studies have found genetic overlaps across neurodevelopmental disorders. This raises the question of whether these genetic overlaps may correlate with phenotypic overlaps and, if so, in what manner. Here, we apply a genome‐wide approach to the study of the linguistic deficit in SLI, autism spectrum disorder (ASD), and attention deficit/hyperactivity disorder (ADHD). Using a discovery genome‐wide association study of SLI, we generate polygenic risk scores (PRS) in an independent sample which includes children with language impairment, SLI, ASD or ADHD and age‐matched controls and perform regression analyses across groups. The SLI‐trained PRS significantly predicted risk in the SLI case–control group (adjusted R² = 6.24%; P = 0.024) but not in the ASD or ADHD case‐control groups (adjusted R² = 0.0004%, 0.01%; P = 0.984, 0.889, respectively) nor for height, used as a negative control (R² = 0.2%; P = 0.452). Additionally, there was a significant difference in the normalized PRS between children with SLI and children with ASD (common language effect size = 0.66; P = 0.044). Our study suggests no additive common‐variant genetic overlap between SLI and ASD and ADHD. This is discussed in the context of phenotypic studies of SLI and related disorders. Autism Res 2020, 13: 369–381. © 2019 The Authors. Autism Research published by International Society for Autism Research published by Wiley Periodicals, Inc.

Lay Summary

Language deficits are characteristic of specific language impairment (SLI), but may also be found in other neurodevelopmental disorders, such as autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD). Many studies examined the overlaps and differences across the language deficits in these disorders, but few studies have examined the genetic aspect thereof. In this study, we use a genome‐wide approach to evaluate whether common genetic variants increasing risk of SLI may also be associated with ASD and ADHD in the same manner. Our results suggest that this is not the case, and we discuss this finding in the context of theories concerning the etiologies of these disorders.

Longitudinal stability of reading profiles in individuals with higher functioning autism

The reading difficulties of individuals with autism spectrum disorders have been established in the literature, with particular attention drawn toward reading comprehension difficulties. Recent papers have highlighted the heterogeneous nature of reading abilities in this population by utilizing statistical methods that allow for investigations of unique reading profiles. This article extends this literature by investigating reading profiles longitudinally, to investigate the stability of reader profiles across time. Latent profile and transition analyses were conducted to establish categorically distinct reading profiles at two time points, 30 months apart. This study also examined whether age and autism symptom severity were related to the profiles at each time point. Finally, transitions between profiles at each time point were identified. Age did not predict profile membership, but there were significant differences in symptom severity that were largely stable over time. Results indicate that heterogeneous reading profiles exist within the autism population, ranging from average reading ability to severe difficulties across different reading subskills. The data from this study demonstrate that reading profiles of children and adolescents with autism spectrum disorders shift when examined across time.

ASD Is Not DLI: Individuals With Autism and Individuals With Syntactic DLI Show Similar Performance Level in Syntactic Tasks, but Different Error Patterns

Do individuals with autism have a developmental syntactic impairment, DLI (formerly known as SLI)? In this study we directly compared the performance of 18 individuals with Autism Spectrum Disorder (ASD) aged 9;0–18;0 years with that of 93 individuals with Syntactic-Developmental Language Impairment (SyDLI) aged 8;8–14;6 (and with 166 typically-developing children aged 5;2–18;1). We tested them using three syntactic tests assessing the comprehension and production of syntactic structures that are known to be sensitive to syntactic impairment: elicitation of subject and object relative clauses, reading and paraphrasing of object relatives, and repetition of complex syntactic structures including Wh questions, relative clauses, topicalized sentences, sentences with verb movement, sentences with A-movement, and embedded sentences. The results were consistent across the three tasks: the overall rate of correct performance on the syntactic tasks is similar for the children with ASD and those with SyDLI. However, once we look closer, they are very different. The types of errors of the ASD group differ from those of the SyDLI group—the children with ASD provide various types of pragmatically infelicitous responses that are not evinced in the SyDLI or in the age equivalent typically-developing groups. The two groups (ASD and SyDLI) also differ in the pattern of performance—the children with SyDLI show a syntactically-principled pattern of impairment, with selective difficulty in specific sentence types (such as sentences derived by movement of the object across the subject), and normal performance on other structures (such as simple sentences). In contrast, the ASD participants showed generalized low performance on the various sentence structures. Syntactic performance was far from consistent within the ASD group. Whereas all ASD participants had errors that can originate in pragmatic/discourse difficulties, seven of them had completely normal syntax in the structures we tested, and were able to produce, understand, and repeat relative clauses, Wh questions, and topicalized sentences. Only one ASD participant showed a syntactically-principled deficit similar to that of individuals with SyDLI. We conclude that not all individuals with ASD have syntactic difficulties, and that even when they fail in a syntactic task, this does not necessarily originate in a syntactic impairment. This shows that looking only at the total score in a syntactic test may be insufficient, and a fuller picture emerges once the performance on different structures and the types of erroneous responses are analyzed.

Speech and language profiles in 4- to 6-year-old children with early diagnosis of autism spectrum disorder without intellectual disability

PURPOSE

This study aimed to present speech and language data from a community-representative group of 4- to 6-year-old children with early-diagnosed autism spectrum disorder (ASD) without intellectual disability (ID).

METHODS

The study group comprised 83 children 4-6 years of age with ASD without ID. They had been diagnosed with ASD before age 4.5 years and had received intervention at a specialized habilitation center. At 2-year follow-up, their language abilities were evaluated comprehensively by two speech-language pathologists using a battery of assessments. Receptive and expressive language and phonology were examined. The phonology evaluation included measures of phonological speech production and of phonological processing.

RESULTS

Results revealed that almost 60% had moderate-severe language problems. Nearly half exhibited combined expressive and receptive language problems, of which a majority also had phonology problems. Phonological speech problems were found in 21% of the total group.

CONCLUSION

The findings underscore the importance of considering speech/language disorders in children with ASD without ID, since they usually attend mainstream classes but need specific educational adaptations.

The role of nonverbal working memory in morphosyntactic processing by children with specific language impairment and autism spectrum disorders

BACKGROUND

Both children with autism spectrum disorders (ASD) and children with specific language impairment (SLI) have been shown to have difficulties with grammatical processing. A comparison of these two populations with neurodevelopmental disorders was undertaken to examine similarities and differences in the mechanisms that may underlie grammatical processing. Research has shown that working memory (WM) is recruited during grammatical processing. The goal of this study was to examine morphosyntactic processing on a grammatical judgment task in children who varied in clinical diagnosis and language abilities and to assess the extent to which performance is predicted by nonverbal working memory (WM). Two theoretical perspectives were evaluated relative to performance on the grammatical judgment task-the "working memory" account and the "wrap-up" account. These accounts make contrasting predictions about the detection of grammatical errors occurring early versus late in the sentence.

METHODS

Participants were 84 school-age children with SLI (n = 21), ASD (n = 27), and typical development (TD, n = 36). Performance was analyzed based on diagnostic group as well as language status (normal language, NL, n = 54, and language impairment, LI, n = 30). A grammatical judgment task was used in which the position of the error in the sentence (early versus late) was manipulated. A visual WM task (N-back) was administered and the ability of WM to predict morphosyntactic processing was assessed.

RESULTS

Groups differed significantly in their sensitivity to grammatical errors (TD > SLI and NL > LI) but did not differ in nonverbal WM. Overall, children in all groups were more sensitive and quicker at detecting errors occurring late in the sentence than early in the sentence. Nonverbal WM predicted morphosyntactic processing across groups, but the specific profile of association between WM and early versus late error detection was reversed for children with and without language impairment.

CONCLUSIONS

Findings primarily support a "wrap up" account whereby the accumulating sentence context for errors positioned late in the sentence (rather than early) appeared to facilitate morphosyntactic processing. Although none of the groups displayed deficits in visual WM, individual differences in these nonverbal WM resources predicted proficiency in morphosyntactic processing.

Intact non-word repetition and similar error patterns in language-matched children with autism spectrum disorders: A pilot study

PURPOSE

We investigated whether enhanced auditory short-term memory may contribute to the learning of novel word forms in children with Autism Spectrum Disorder. We also evaluated whether delayed but qualitatively normal, versus atypical, cognitive processes underlie non-word repetition in this population via a detailed error analysis.

METHOD

English-speaking children with Autism Spectrum Disorder (who had significant language delay) and typically-developing children matched pairwise on language ability were compared on the Syllable Repetition Task (Shriberg et al., 2009).

RESULTS

All children exhibited better performance on stimuli of shorter vs. longer syllable length. In addition there was a significant interaction whereby children with Autism Spectrum Disorder performed better than typically-developing children at the longest syllable length. Repetition accuracy was significantly correlated with language level in both groups. In contrast, the relationship between Repetition accuracy and age was only marginally significant in the Autism Spectrum Disorder group and did not reach significance in the typically-developing group. This underscores the importance of language level to non-word repetition performance, and supports the practice of matching on language rather than age alone. An error analysis (Shriberg et al., 2012) showed many similarities between groups in terms of number of consonants deleted, encoding accuracy, and transcoding accuracy components of the task. However the Autism Spectrum Disorder group tended to display better auditory short-term memory with a medium effect size, though this did not reach significance given the small sample size.

CONCLUSION

These findings extend evidence of delayed but qualitatively normal non-word repetition previously described in preadolescents with Autism Spectrum Disorder (Williams et al., 2013) to younger kindergarten-age children with Autism Spectrum Disorder and language delay, indicating that non-word repetition is not an area of specific difficulty for this population. With respect to enhanced auditory short-term memory, we found preliminary evidence of better memory for longer nonwords in children with Autism Spectrum Disorder compared to younger typically developing children who were matched on language.

CATALISE: A Multinational and Multidisciplinary Delphi Consensus Study. Identifying Language Impairments in Children

Delayed or impaired language development is a common developmental concern, yet there is little agreement about the criteria used to identify and classify language impairments in children. Children's language difficulties are at the interface between education, medicine and the allied professions, who may all adopt different approaches to conceptualising them. Our goal in this study was to use an online Delphi technique to see whether it was possible to achieve consensus among professionals on appropriate criteria for identifying children who might benefit from specialist services. We recruited a panel of 59 experts representing ten disciplines (including education, psychology, speech-language therapy/pathology, paediatrics and child psychiatry) from English-speaking countries (Australia, Canada, Ireland, New Zealand, United Kingdom and USA). The starting point for round 1 was a set of 46 statements based on articles and commentaries in a special issue of a journal focusing on this topic. Panel members rated each statement for both relevance and validity on a seven-point scale, and added free text comments. These responses were synthesised by the first two authors, who then removed, combined or modified items with a view to improving consensus. The resulting set of statements was returned to the panel for a second evaluation (round 2). Consensus (percentage reporting 'agree' or 'strongly agree') was at least 80 percent for 24 of 27 round 2 statements, though many respondents qualified their response with written comments. These were again synthesised by the first two authors. The resulting consensus statement is reported here, with additional summary of relevant evidence, and a concluding commentary on residual disagreements and gaps in the evidence base.

Shared neuroanatomical substrates of impaired phonological working memory across reading disability and autism

BACKGROUND

Individuals with reading disability or individuals with autism spectrum disorder (ASD) are characterized, respectively, by their difficulties in reading or social communication, but both groups often have impaired phonological working memory (PWM). It is not known whether the impaired PWM reflects distinct or shared neuroanatomical abnormalities in these two diagnostic groups.

METHODS

White-matter structural connectivity via diffusion weighted imaging was examined in sixty-four children, ages 5-17 years, with reading disability, ASD, or typical development (TD), who were matched in age, gender, intelligence, and diffusion data quality.

RESULTS

Children with reading disability and children with ASD exhibited reduced PWM compared to children with TD. The two diagnostic groups showed altered white-matter microstructure in the temporo-parietal portion of the left arcuate fasciculus (AF) and in the temporo-occipital portion of the right inferior longitudinal fasciculus (ILF), as indexed by reduced fractional anisotropy and increased radial diffusivity. Moreover, the structural integrity of the right ILF was positively correlated with PWM ability in the two diagnostic groups, but not in the TD group.

CONCLUSIONS

These findings suggest that impaired PWM is transdiagnostically associated with shared neuroanatomical abnormalities in ASD and reading disability. Microstructural characteristics in left AF and right ILF may play important roles in the development of PWM. The right ILF may support a compensatory mechanism for children with impaired PWM.

Representation of spectro-temporal features of spoken words within the P1-N1-P2 and T-complex of the auditory evoked potentials (AEP)

The purpose of the study was to determine whether P1-N1-P2 and T-complex morphology reflect spectro-temporal features within spoken words that approximate the natural variation of a speaker and whether waveform morphology is reliable at group and individual levels, necessary for probing auditory deficits. The P1-N1-P2 and T-complex to the syllables /pət/ and /sət/ within 70 natural word productions each were examined. EEG was recorded while participants heard nonsense word pairs and performed a syllable identification task to the second word in the pairs. Single trial auditory evoked potentials (AEP) to the first words were analyzed. Results found P1-N1-P2 and T-complex to reflect spectral and temporal feature processing. Also, results identified preliminary benchmarks for single trial response variability for individual subjects for sensory processing between 50 and 600ms. P1-N1-P2 and T-complex, at least at group level, may serve as phenotypic signatures to identify deficits in spectro-temporal feature recognition and to determine area of deficit, the superior temporal plane or lateral superior temporal gyrus.

Evidence for shared deficits in identifying emotions from faces and from voices in autism spectrum disorders and specific language impairment

BACKGROUND

While autism spectrum disorder (ASD) and specific language impairment (SLI) have traditionally been conceptualized as distinct disorders, recent findings indicate that the boundaries between these two conditions are not clear-cut. While considerable research has investigated overlap in the linguistic characteristics of ASD and SLI, relatively less research has explored possible overlap in the socio-cognitive domain, particularly in terms of the emotion recognition abilities of these two groups of children.

AIMS

To investigate facial and vocal emotion recognition in children with ASD, children with SLI and typically developing (TD) children. To do so, the ASD group was subdivided into those with 'normal' (ALN) and those with 'impaired' (ALI) language to explore the extent to which language ability influenced performance on the emotion recognition task.

METHODS & PROCEDURES

Twenty-nine children with ASD (17 ALN and 12 ALI), 18 children with SLI and 66 TD children completed visual and auditory versions of an emotion recognition task. For the visual version of the task, the participants saw photographs of people expressing one of six emotions (happy, sad, scared, angry, surprised, disgusted) on the whole face. For the auditory modality, the participants heard a neutral sentence that conveyed one of the six emotional expressions in the tone of the voice. In both conditions, the children were required to indicate how the person they could see/hear was feeling by selecting a cartoon face that was presented on the computer screen.

OUTCOMES & RESULTS

The results showed that all clinical groups were less accurate than the TD children when identifying emotions on the face and in the voice. While the ALN children were less accurate than the TD children only when identifying expressions that require inferring another's mental state (surprise, disgust) emotional expressions, the ALI and the SLI children were less accurate than the TD children when identifying the basic (happy, sad, scared, angry) as well as the inferred emotions.

CONCLUSIONS & IMPLICATIONS

The results indicate that children with ALI and children with SLI share emotion recognition deficits, which are likely to be driven by the poor language abilities of these two groups.

Memory in language-impaired children with and without autism

Background

A subgroup of young children with autism spectrum disorders (ASD) have significant language impairments (phonology, grammar, vocabulary), although such impairments are not considered to be core symptoms of and are not unique to ASD. Children with specific language impairment (SLI) display similar impairments in language. Given evidence for phenotypic and possibly etiologic overlap between SLI and ASD, it has been suggested that language-impaired children with ASD (ASD + language impairment, ALI) may be characterized as having both ASD and SLI. However, the extent to which the language phenotypes in SLI and ALI can be viewed as similar or different depends in part upon the age of the individuals studied. The purpose of the current study is to examine differences in memory abilities, specifically those that are key “markers” of heritable SLI, among young school-age children with SLI, ALI, and ALN (ASD + language normal).

Methods

In this cross-sectional study, three groups of children between ages 5 and 8 years participated: SLI (n = 18), ALI (n = 22), and ALN (n = 20). A battery of cognitive, language, and ASD assessments was administered as well as a nonword repetition (NWR) test and measures of verbal memory, visual memory, and processing speed.

Results

NWR difficulties were more severe in SLI than in ALI, with the largest effect sizes in response to nonwords with the shortest syllable lengths. Among children with ASD, NWR difficulties were not associated with the presence of impairments in multiple ASD domains, as reported previously. Verbal memory difficulties were present in both SLI and ALI groups relative to children with ALN. Performance on measures related to verbal but not visual memory or processing speed were significantly associated with the relative degree of language impairment in children with ASD, supporting the role of verbal memory difficulties in language impairments among early school-age children with ASD.

Conclusions

The primary difference between children with SLI and ALI was in NWR performance, particularly in repeating two- and three-syllable nonwords, suggesting that shared difficulties in early language learning found in previous studies do not necessarily reflect the same underlying mechanisms.

Electronic supplementary material

The online version of this article (doi:10.1186/s11689-015-9111-z) contains supplementary material, which is available to authorized users.

Unraveling the nature of autism: finding order amid change

In this article, we hypothesize that individuals with autism spectrum disorder (ASD) are born with a deficit in invariance detection, which is a learning process whereby people and animals come to attend the relatively stable patterns or structural regularities in the changing stimulus array. This paper synthesizes a substantial body of research which suggests that a deficit in the domain-general perceptual learning process of invariant detection in ASD can lead to a cascade of consequences in different developmental domains. We will outline how this deficit in invariant detection can cause uncertainty, unpredictability, and a lack of control for individuals with ASD and how varying degrees of impairments in this learning process can account for the heterogeneity of the ASD phenotype. We also describe how differences in neural plasticity in ASD underlie the impairments in perceptual learning. The present account offers an alternative to prior theories and contributes to the challenge of understanding the developmental trajectories that result in the variety of autistic behaviors.

Evidence for distinct cognitive profiles in autism spectrum disorders and specific language impairment

Findings that a subgroup of children with an autism spectrum disorder (ASD) have linguistic capabilities that resemble specific language impairment (SLI) have led some authors to hypothesise that ASD and SLI have a shared aetiology. While considerable research has explored overlap in the language phenotypes of the two conditions, little research has examined possible overlap in cognitive characteristics. In this study, we explored nonword and sentence repetition performance, as well as performance on the Children's Embedded Figures Test (CEFT) for children with ASD or SLI. As expected, 'language impaired' children with ASD (ALI) and children with SLI performed worse than both 'language normal' ASD (ALN) and typically developing (TD) children on the nonword and sentence repetition tests. Further, the SLI children performed worse than all other groups on the CEFT. This finding supports distinct cognitive profiles in ASD and SLI and may provide further evidence for distinct aetiological mechanisms in the two conditions.

The filtered words test and the influence of lexicality

PURPOSE

In the present study, the authors aimed to investigate the language confounds of filtered words tests by examining the repetition of real words versus nonsense words as a function of level of filtering.

METHOD

Fifty-five young, native-English-speaking women with normal hearing were required to repeat 80 real-word and 80 nonsense-word monosyllables that were matched for phonemic content and low-pass filtered. Thirty participants were tested using a harsher filter range of 2000 to 500 Hz, and 25 participants were tested using a milder filter range of 3000 to 1500 Hz.

RESULTS

Paired-sample t tests compared accuracy (percentage of phonemes correct) for word and nonsense-word stimuli at each filter level. At filter levels between 3000 and 1750 Hz, performance for word stimuli was significantly better than for nonsense-word stimuli. Conversely, at filter levels between 500 and 1250 Hz, performance was significantly better for nonsense words.

CONCLUSIONS

The linguistic content of real-word stimuli benefits performance on low-pass filtered speech tests at filter levels above 1500 Hz. Caution must be taken when using real-word stimuli in low-pass filtered speech tests as part of an auditory processing diagnostic test battery, because language ability will impact on performance.

Left hemisphere diffusivity of the arcuate fasciculus: influences of autism spectrum disorder and language impairment

BACKGROUND AND PURPOSE

There has been much discussion whether brain abnormalities associated with specific language impairment and autism with language impairment are shared or are disorder specific. Although white matter tract abnormalities are observed in both specific language impairment and autism spectrum disorders, the similarities and differences in the white matter abnormalities in these 2 disorders have not been fully determined.

MATERIALS AND METHODS

Diffusion tensor imaging diffusion parameters of the arcuate fasciculus were measured in 14 children with specific language impairment as well as in 16 children with autism spectrum disorder with language impairment, 18 with autism spectrum disorder without language impairment, and 25 age-matched typically developing control participants.

RESULTS

Language impairment and autism spectrum disorder both had (elevating) main effects on mean diffusivity of the left arcuate fasciculus, initially suggesting a shared white matter substrate abnormality. Analysis of axial and radial diffusivity components, however, indicated that autism spectrum disorder and language impairment differentially affect white matter microstructural properties, with a main effect of autism spectrum disorder on axial diffusivity and a main effect of language impairment on radial diffusivity.

CONCLUSIONS

Although white matter abnormalities appear similar in language impairment and autism spectrum disorder when examining broad white matter measures, a more detailed analysis indicates different mechanisms for the white matter microstructural anomalies associated with language impairment and autism spectrum disorder.

Word production errors in children with developmental language impairments

This review focuses on the errors that children with developmental language impairments make on three types of word production tasks: lexical retrieval, the elicitation of derivationally complex forms and the repetition of non-sense forms. The studies discussed in this review come principally from children with specific language impairment, and from children who are English-speakers or deaf users of British sign language. It is argued that models of word production need to be able to account for the data presented here, and need to have explanatory power across both modalities (i.e. speech and sign).

Diminished time-based, but undiminished event-based, prospective memory among intellectually high-functioning adults with autism spectrum disorder: relation to working memory ability

Objective: Prospective memory (PM) is the ability to remember to carry out an intended action. Working memory is the ability to store information in mind while processing potentially distracting information. The few previous studies of PM in autism spectrum disorder (ASD) have yielded inconsistent findings. Studies of working memory ability in ASD have suggested a selective impairment of “visual working memory.” However, it remains unclear whether any such impairment is the result of diminished (domain-specific; visual/verbal) storage capacity or diminished (domain-general) processing capacity. We aim to clarify these issues and explore the relation between PM and working memory in ASD. Method: Seventeen adults with ASD and 17 age- and IQ-matched comparison participants completed experimental measures of both event-based (perform action x when event y occurs) and time-based (perform action a at time b) PM, plus a self-report measure of PM skills. Participants also completed a working memory test battery. Results: Participants with ASD self-reported diminished PM skill, and showed diminished performance on the time-based, but not event-based, PM task. On the working memory test battery, visual but not verbal storage capacity was diminished among participants with ASD, as was processing ability. Whereas visual storage was associated with event-based PM task performance among comparison participants, verbal storage was associated among ASD participants. Conclusions: ASD appears to involve a selective deficit in time-based PM and a selective difficulty with aspects of working memory that depend on the storage of visual information. However, event-based PM may be achieved through compensatory strategies in ASD.

Developmental language disorders: challenges and implications of cross-group comparisons

Historically, specific language impairment (SLI) and language deficits associated with autism spectrum disorders (ASD) have been viewed as distinct developmental language disorders. However, over the last decade or so, a considerable amount of research has explored general similarities or specific areas of overlap between children with SLI and ASD based on language and cognitive profiles, neuroimaging findings, and genetic research. The clinical classification schemes that are used to identify the children necessarily influence the extent to which SLI and ASD are viewed as overlapping or distinct conditions. Yet, the criteria used to diagnose these two populations vary across countries and even across investigators within a given country. This necessarily impacts the findings from comparative investigations of these groups. With these challenges in mind, clinical implications of evidence for similarities and distinctions between children with SLI and ASD will be discussed with respect to differential diagnosis and treatment.