What Silent Pauses Can 'Tell' Us About the Storytelling Skills of Autistic Children: Relations Between Pausing, Language Skills and Executive Functions.

Silent pauses may serve communicative purposes such as demarcating boundaries between discourse units in language production. Previous research has shown that autistic children differ in their pausing behavior from typically-developing (TD) peers, however, the factors behind this difference remain underexplored. The current study was aimed at comparing the use of silent pauses in the narrative production of autistic children and age-matched TD children, and also to identify possible relations between pausing behavior and the children's language and executive function abilities. According to the study's findings, the autistic children did not differ from their TD peers in the use of grammatical pauses, however, the former tended to produce significantly less syntactically complex narratives than the TD group, which increased the likelihood that the autistic group would pause appropriately at phrasal boundaries. Though we have found low rates of ungrammatical silent pauses and omitted pauses in obligatory discourse contexts across both groups, autistic children with lower cognitive flexibility tended to use more ungrammatical pauses than their peers with higher cognitive flexibility scores. Also, the autistic group tended to omit obligatory silent pauses more often as their narration became more complex. The results demonstrate that syntactic complexity in narrative production modulated autistic children's pausing behavior, and that structurally simple narrations boosted the autistic group's appropriate use of grammatical pauses. The overall findings also demonstrate the importance of studying silent pauses in the narrative discourse of autistic children, and also highlight the links between silent pauses and the children's syntactic and cognitive skills.

Metaphor comprehension and production in verbally able children with Autism Spectrum Disorder.

Research in the field of figurative language processing in Autism Spectrum Disorders (ASD) has demonstrated that autistic individuals experience systematic difficulties in the comprehension of different types of metaphors. However, there is scarce evidence regarding metaphor production skills in ASD. Importantly, the exact source of metaphor processing difficulties in ASD remains largely controversial. The debate has mainly focused on the mediating role of structural language skills (i.e., lexical knowledge) and cognitive abilities (i.e., Theory of Mind and executive functions) in ASD individuals' ability to comprehend and generate metaphors. The present study examines metaphor comprehension and production in 18 Greek-speaking verbally able children with ASD and 31 typically-developing (TD) controls. Participants completed two tasks, namely, a low-verbal multiple-choice sentence-picture matching task that tested their ability to comprehend conventional predicate metaphors, and a sentence continuation task that assessed their ability to generate metaphors. The study also included measures of fluid intelligence, expressive vocabulary, and working memory within the sample. The results show that the ASD group had significantly lower performance than the TD group in both metaphor comprehension and production. The findings also reveal that expressive vocabulary skills were a key factor in the metaphor comprehension and production performance of the children with ASD. Working memory capacity was also found to correlate significantly with metaphor comprehension performance in the ASD group. Conversely, no correlations were found in the TD group with neither of the above factors. Of note, children with ASD generated significantly more inappropriate responses and no-responses to the metaphor production task compared with the control group. The overall results reveal that children with ASD had difficulty with both comprehending and using metaphorical language. The findings also indicate that TD children may employ diverse cognitive strategies or rely on different underlying skills when processing metaphors compared with children with ASD.

Bilingualism and second-order theory of mind development in autistic children over time: Longitudinal relations with language, executive functions, and intelligence.

Theory of Mind has long been studied as a core weakness in autism spectrum disorder due to its relationship with social reciprocity, while bilingualism has been shown to compensate for autistic individuals' mentalizing weaknesses. However, our knowledge of the Theory of Mind developmental trajectories of bilingual and monolingual autistic children, as well as of the factors related to Theory of Mind development in autism spectrum disorder is still limited. The current study has examined first- and second-order Theory of Mind skills in 21 monolingual and 21 bilingual autistic children longitudinally across three time points, specifically at ages 6, 9, and 12, and also investigated associations between Theory of Mind trajectories and trajectories of the children's language, intelligence and executive function skills. The results reveal that bilingual autistic children outperformed their monolingual peers in second-order Theory of Mind at ages 9 and 12, and that intelligence and, especially, expressive vocabulary skills played a pivotal role in advancing bilingual autistic children's second-order Theory of Mind development. On the other hand, monolingual autistic children only managed to capitalize on their language and intelligence resources at age 12. The findings highlight the importance of investigating bilingualism effects on autistic children's advanced cognitive abilities longitudinally.

Autism Detection in Children: Integrating Machine Learning and Natural Language Processing in Narrative Analysis.

Despite the consensus that early identification leads to better outcomes for individuals with autism spectrum disorder (ASD), recent research reveals that the average age of diagnosis in the Greek population is approximately six years. However, this age of diagnosis is delayed by an additional two years for families from lower-income or minority backgrounds. These disparities result in adverse impacts on intervention outcomes, which are further burdened by the often time-consuming and labor-intensive language assessments for children with ASD. There is a crucial need for tools that increase access to early assessment and diagnosis that will be rigorous and objective. The current study leverages the capabilities of artificial intelligence to develop a reliable and practical model for distinguishing children with ASD from typically-developing peers based on their narrative and vocabulary skills. We applied natural language processing-based extraction techniques to automatically acquire language features (narrative and vocabulary skills) from storytelling in 68 children with ASD and 52 typically-developing children, and then trained machine learning models on the children's combined narrative and expressive vocabulary data to generate behavioral targets that effectively differentiate ASD from typically-developing children. According to the findings, the model could distinguish ASD from typically-developing children, achieving an accuracy of 96%. Specifically, out of the models used, hist gradient boosting and XGBoost showed slightly superior performance compared to the decision trees and gradient boosting models, particularly regarding accuracy and F1 score. These results bode well for the deployment of machine learning technology for children with ASD, especially those with limited access to early identification services.

Reading comprehension differences between children with Autism Spectrum Disorder and low cognitive abilities and children with Autism Spectrum Disorder and intact cognitive skills: the roles of decoding, fluency and morphosyntax.

Introduction: Reading comprehension is one of the most important skills learned in school and it has an important contribution to the academic success of children with Autism Spectrum Disorder (ASD). Though previous studies have investigated reading comprehension difficulties in ASD and highlighted factors that contribute to these difficulties, this evidence has mainly stemmed from children with ASD and intact cognitive skills. Also, much emphasis has been placed on the relation between reading comprehension and word recognition skills, while the role of other skills, including fluency and morphosyntax, remains underexplored. This study addresses these gaps by investigating reading comprehension in two groups of school-aged children with ASD, one with intact and one with low cognitive abilities, also exploring the roles of word decoding, fluency and morphosyntax in each group's reading comprehension performance. Methods: The study recruited 16 children with ASD and low cognitive abilities, and 22 age-matched children with ASD and intact cognitive skills. The children were assessed on four reading subdomains, namely, decoding, fluency, morphosyntax, and reading comprehension. Results: The children with ASD and low cognitive abilities scored significantly lower than their peers with intact cognitive abilities in all reading subdomains, except for decoding, verb production and compound word formation. Regression analyses showed that reading comprehension in the group with ASD and intact cognitive abilities was independently driven by their decoding and fluency skills, and to a lesser extent, by morphosyntax. On the other hand, the children with ASD and low cognitive abilities mainly drew on their decoding, and to a lesser extent, their morphosyntactic skills to perform in reading comprehension. Discussion: The results suggest that reading comprehension was more strongly affected in the children with ASD and low cognitive abilities as compared to those with intact cognitive skills. About half of the children with ASD and intact cognitive skills also exhibited mild-to-moderate reading comprehension difficulties, further implying that ASD may influence reading comprehension regardless of cognitive functioning. Finally, strengths in decoding seemed to predominantly drive cognitively-impaired children's reading performance, while the group with ASD and intact cognitive skills mainly recruited fluency and metalinguistic lexical skills to cope with reading comprehension demands, further suggesting that metalinguistic awareness may be a viable way to enhance reading comprehension in ASD.

Intellectual development in young children with autism spectrum disorders: A longitudinal study.

Intelligence profiles in autism have been characterized by great variability. The questions of how autistic children's intelligence changes over time, and what factors influence these changes deserve study as part of efforts to document child autism profiles, but also because the relationship between intellectual functioning and children's background characteristics is poorly understood, particularly in a longitudinal context. A total of 39 autistic children and 39 age-matched neurotypical children (5-9 years old) completed two IQ assessments at preschool age and up to 4 years later. Repeated-measures analyses assessed longitudinal changes in the children's verbal (VIQ), performance (PIQ), and full-scale IQ (FSIQ) at group level. We further sought to identify clusters with distinct profiles in each group by adopting an unsupervised K-means clustering approach, and detect possible between-subgroup differences in terms of children's socioeconomic status and autism severity. The largest cluster in the autistic group was composed of children whose PIQ significantly dropped at follow-up, while the second largest cluster improved in all quotients; the smallest cluster, wherein children had more highly educated mothers than the rest of the clusters, was characterized by large improvement in VIQ. For the neurotypical children, there was a two-cluster division; the majority of them improved in the three quotients, while very few dropped in PIQ at follow-up. The relation between socioeconomic status and IQ changes was significant for both groups. The findings demonstrate both the complexity of intelligence changes in autism and the need to view this complexity through the lens of the children's socioeconomic diversity.

Figurative language processing in autism spectrum disorders: A review.

Impairments in the broader domain of pragmatics are considered to be a defining feature of Autism Spectrum Disorders (ASD). A challenging aspect of pragmatic competence is the ability to process nonliteral language. Interestingly, previous studies in figurative language comprehension in ASD have demonstrated conflicting results regarding participants' performance. The main scientific debate focuses on the underlying skills which facilitate processing of nonliteral speech in ASD. Namely, Theory of Mind (ToM), language abilities and Executive functions (EFs) are regarded as factors affecting autistic individuals' performance. This review addresses figurative language comprehension in ASD in light of the above three interpretive accounts. We reviewed data from recent studies in this field concluding that autistic children indeed encounter systematic difficulties in the processing of non-literal language. Moreover, only ToM and verbal skills were found to correlate the most with figurative language comprehension in ASD. Notably, we found that differences related to research methodology and tasks' properties may have led to discrepancies between studies' results. Finally, we argue that future studies should encompass in their experimental design figurative comprehension tasks with minimal linguistic demands and also measures of ToM, verbal ability and EFs in order to shed more light in the independent contribution of those skills to the processing of nonliteral language in ASD.

Animacy Processing in Autism: Event-Related Potentials Reflect Social Functioning Skills.

Though previous studies with autistic individuals have provided behavioral evidence of animacy perception difficulties, the spatio-temporal dynamics of animacy processing in autism remain underexplored. This study investigated how animacy is neurally encoded in autistic adults, and whether potential deficits in animacy processing have cascading deleterious effects on their social functioning skills. We employed a picture naming paradigm that recorded accuracy and response latencies to animate and inanimate pictures in young autistic adults and age- and IQ-matched healthy individuals, while also employing high-density EEG analysis to map the spatio-temporal dynamics of animacy processing. Participants' social skills were also assessed through a social comprehension task. The autistic adults exhibited lower accuracy than controls on the animate pictures of the task and also exhibited altered brain responses, including larger and smaller N100 amplitudes than controls on inanimate and animate stimuli, respectively. At late stages of processing, there were shorter slow negative wave latencies for the autistic group as compared to controls for the animate trials only. The autistic individuals' altered brain responses negatively correlated with their social difficulties. The results suggest deficits in brain responses to animacy in the autistic group, which were related to the individuals' social functioning skills.

The Acquisition of Relative Clauses in Autism: The Role of Executive Functions and Language.

PURPOSE: Relative clauses present a well-known processing asymmetry between object-extracted and subject-extracted dependencies across both typical and atypical populations. The present study aimed at exploring the comprehension of object and subject relative clauses as conceptualized by the Relativized Minimality framework in autistic children and in a group of age- and IQ-matched typically-developing children. The study also explored the way performance in relative clauses would be affected by the children's language and executive function skills. METHOD: Relative clause comprehension was tested through a sentence-picture matching task and language was tested with a receptive vocabulary task. Executive functions were assessed through backward digit recall and a Flanker test. RESULTS: Object relative clauses were harder to parse for both groups than subject relatives, while number mismatch between the moved object Noun Phrase and the intervening subject Noun Phrase in object relatives boosted both groups' performances. Typically-developing children's performance in object relatives was predicted by both language and executive functions, while autistic children failed to use language and did not systematically draw on their executive functions in object relative clause comprehension. CONCLUSION: The findings suggest that relative clause processing in autism follows a normal developmental trajectory, and that difficulty with parsing object relative clauses stems from reduced language and executive functions rather than deficits in the children's morphosyntactic skills.

Disentangling Language Disorder and Bilingualism in Children with Developmental Language Disorder and Autism Spectrum Disorder: Evidence from Writing.

Twenty-eight Albanian-Greek bilingual children with Developmental Language Disorder and 28 children with Autism Spectrum Disorder but no language impairment, along with 28 typically-developing, age-, Performance IQ- and socioeconomic status-matched bilingual children were asked to produce two expository texts which were coded for spelling (phonological, grammatical, orthographic) errors, stress and punctuation use. The children's expressive vocabulary, current language use and home language history were also measured. The results show that the bilingual children with Developmental Language Disorder were particularly vulnerable to spelling errors, while their bilingual peers with Autism Spectrum Disorder were rather challenged by stress and punctuation. The evidence speaks in favor of distinct patterns of writing impairment across the bilingual children with Developmental Language Disorder and Autism Spectrum Disorder.

TREM2 R47H variant and risk for Alzheimer's disease: assessment in a Greek population and updated meta-analysis.

INTRODUCTION: Rare coding variants in TREM2 and their association with the susceptibility towards Alzheimer's disease (AD) were recently studied in various ethnic groups with contradictory results. The T allele of the rs75932628 (p.R47H variant) has shown a positive risk association with AD in several studies; however, neither a study in Greece nor an updated meta-analysis have been conducted. OBJECTIVE: To assess the association between TREM2 rs75932628 and late-onset (sporadic) AD in a Greek population, and perform a meta-analysis of current data. MATERIALS AND METHODS: The rs75932628 was genotyped in a total of 327 patients with AD and 700 cognitively healthy controls. A systematic search and meta-analyses of studies presenting data regarding rs75932628 in AD cases and controls were also performed. RESULTS: Three patients vs. none of the controls were found to carry the heterozygous risk allele of the rs75932628, yielding a significant association (p = 0.032), in the Greek sample. In the meta-analysis, the overall odds ratio (OR) under a fixed-effects model was 2.98 (Confidence Interval (CI):2.52-3.53) showing a significant association of the rs75932628-T allele with AD in the overall dataset, based on data from 27 studies (26200 AD cases and 142084controls). Caucasian population-only studies (n = 16) revealed a similar OR of 2.93 (CI:2.45-3.51), whereas Asian population-only studies (n = 5) had a non-significant OR of 0.84 (CI:0.19-3.74). CONCLUSION: The rs75932628 was associated with AD in the Greek sample. Our meta-analysis, covering a total population of over 168,000 people, also showed a significant association of the allele with AD in Caucasian populations.

Cognitive flexibility in autism: Evidence from young autistic children.

We examined the cognitive flexibility performance of young autistic children and a group of neurotypical peers. Thirty-six autistic children (72-83 months) and 200 age-matched typically-developing children were assessed on the Children's Color Trails Test (CCTT), a semantic and a phonemic verbal fluency task. The results showed that the autistic children performed worse than their neurotypical peers in the switching component of the CCTT. In the fluency tests, the autistic group generated overall fewer word items than their neurotypical peers, however, their poorer performance was driven by specific linguistic stimuli in the fluency tasks. The findings suggest that cognitive flexibility for the autistic children was affected in the nonverbal CCTT only, while poor performance in semantic and phonemic fluency seemed to be inherent to the language properties of the verbal fluency tasks.

Effects of low doses of different nitric oxide (NO) donors in rat models of obsessive-compulsive disorder (OCD) and posttraumatic stress disorder (PTSD).

Several lines of evidence suggest that the intra- and inter-cellular messenger nitric oxide (NO) is critically involved in anxiety. Contrasting findings are reported, however, regarding the effects of NO donors in preclinical models of anxiety. Previous research has shown that challenge with a low dose range of the NO donors sodium nitroprusside (SNP) and molsidomine induce anti-anxiety-like effects in rodents. There is poor information concerning the effects of these NO donors on preclinical models mimicking the obsessive-compulsive disorder (OCD) and the post-traumatic stress disorder (PTSD). The present research was designed to investigate this issue in the rat. To this end, the mCPP-induced excessive self-grooming and the contextual fear conditioning (CFC) test which are behavioural paradigms resembling OCD and PTSD respectively in rodents were used. Acute administration of SNP (1 mg/kg) and molsidomine (4 mg/kg) attenuated excessive self-grooming induced by the 5-HT2C receptor agonist mCPP (0.6 mg/kg). Further, at the same dosage, both these NO donors reduced freezing behaviour evidenced in the CFC test. The present results suggest that NO donors are efficacious in attenuating abnormal behaviours revealed in animal models of OCD and PTSD which are among the most severe pathologies of anxiety.

Bilingualism effects on cognition in autistic children are not all-or-nothing: The role of socioeconomic status in intellectual skills in bilingual autistic children.

LAY ABSTRACT: Previous research has suggested that bilingualism may improve cognition in children with autism, and that this boost may stem from improvement in executive functions. The Wechsler Intelligence Scales for Children are considered to be reliable and valid measures of intelligence when administered to autistic children. These measures have so far revealed unusual psychometric properties in monolingual autistic children, notably distinctive patterns of strengths and weaknesses and low inter-correlation among verbal and nonverbal IQ subtests. The way bilingualism affects the intellectual functioning of autistic children has not been explored yet. Nor has there been a satisfactory factor structure that explains monolingual and bilingual autistic children's IQ performance in terms of individual factors, such as age and socioeconomic status. The current study examined the intelligence profiles of 316 bilingual and age- and gender-matched monolingual children with autism using the Wechsler Intelligence Scales for Children-Third Edition. The study applied clustering models to extract intelligence subtypes of autism, and mediation analyses to examine potential mediation effects of age and socioeconomic status on the children's verbal and nonverbal IQ performance. The results support the mediational role of the children's socioeconomic status in the association between bilingualism and intelligence. Low-socioeconomic status bilingual autistic children outperformed their monolingual peers on both verbal and nonverbal subtests, while the differences faded in medium-socioeconomic status and high-socioeconomic status children. The findings emphasize the positive effects of bilingualism on low-socioeconomic status autistic children's intelligence and also highlight high-socioeconomic status as a factor that may mitigate discrepant patterns of strengths and weaknesses in monolingual children's IQ performance.

Bilingualism effects in pronoun comprehension: Evidence from children with autism.

The prevalence of autism worldwide has risen steadily in the last two decades, while bilingualism is also becoming increasingly prevalent in today's rapidly globalizing world. The current study aimed to investigate bilingualism effects in the pronoun resolution skills of children with autism in comparison to age-matched monolingual children with autism, as well as monolingual and bilingual children of typical development (Ν = 20 participants per group). Results showed that autistic children had general difficulty anchoring ambiguous pronouns to entities that were linguistically expressed in discourse, yet, the bilingual children with autism were more sensitive to the topicality of the entities in syntactic subject position and more prone to identify them as suitable referents of ambiguous null pronouns as compared to their monolingual peers. The findings suggest that bilingualism is not detrimental to autistic children's pronoun resolution skills. The current study aimed at determining how bilingualism influences ambiguous pronoun comprehension in children with autism as compared to bilingual and monolingual children of typical development. The findings show that bilingualism was not detrimental to the autistic children's pronoun resolution skills, further suggesting that having acquired more than one language does not exacerbate autistic children's deficits in the comprehension of pronouns.

Therapeutic application of rTMS in neurodegenerative and movement disorders: A review.

Transcranial magnetic stimulation (TMS) is a non-invasive form of brain stimulation that makes use of the magnetic field generated when an electric current passes through a magnetic coil placed over the scalp. It can be applied as a single stimulus at a time, in pairs of stimuli, or repetitively in trains of stimuli (repetitive TMS, rTMS). RTMS can induce changes in brain activity, whose after-effects reflect the processes of long-term potentiation and long-term depression, as certain protocols, namely those using low frequencies (≤1 Hz) seem to suppress cortical excitability, while those using high frequencies (>1 Hz) seem to enhance it. It is a technique with very few and mostly mild side-effects, whose effects can persist for long time periods, and as such, it has been studied as a potential treatment option in a multitude of neurodegenerative diseases, including those affecting movement. Although rTMS has received approval as a treatment strategy of only a few aspects in movement disorders in the latest guidelines, its further use seems to also be promising in their context. In this review, we gathered the available literature on the therapeutic application of rTMS in movement disorders, namely Parkinson's disease, Amyotrophic Lateral Sclerosis, Huntington's disease, Dystonia, Tic disorders and Essential Tremor.

The Impact of Primary Progressive Aphasia on Picture Naming and General Language Ability.

BACKGROUND: Primary progressive aphasia (PPA) is a clinical syndrome that is characterized by progressive deterioration of language while other cognitive domains remain relatively intact. The extent to which print exposure and cortical volume atrophy jointly influence picture naming and general language ability in individuals with PPA remains underexplored. OBJECTIVE: To investigate the language performance of individuals with the nonfluent variant of primary progressive aphasia (nfvPPA) and to explore the impact of print exposure and cortical volume atrophy on their language ability. METHOD: We compared 14 Greek individuals with nfvPPA and similar age, education, disease duration, and cognitive ability with age-, gender- and education-matched Greek controls on picture naming and on language tasks of the Boston Diagnostic Aphasia Examination-Short Form, including oral word reading, word and sentence repetition, complex ideational material, and reading comprehension. The effects of print exposure and left-hemisphere cortical volume on the individuals' language performance were estimated through stepwise regression models. RESULTS: The language performance of the individuals with nfvPPA was affected by print exposure and cortical volume atrophy. Picture naming and word reading were affected by print exposure. The highest contributions of cortical volume atrophy were found for the repetition, complex ideational material, and reading comprehension tasks. CONCLUSION: Print exposure and cortical volume atrophy may help explain variability in the language performance of nfvPPA individuals with similar age, education, disease duration, and cognitive ability.