Executive dysfunction and its relation to language ability in verbal school-age children with autism

The Basic Units of Working Memory Manipulation Are Boolean Maps, Not Objects

Determining the manipulation unit of working memory is one of the fundamental questions in understanding how working memory functions. The prevalent object-based theory in cognitive research predicts that memory manipulation is performed on the level of objects. Here we show instead that the basic units of working memory manipulation are Boolean maps, a data structure describing what can be perceived in an instant. We developed four new manipulation tasks (with data from 80 adults) and showed that manipulation times only increased when the number of Boolean maps manipulated increased. Increasing the number of orientations manipulated did not induce longer manipulation times, consistent with a key prediction of the Boolean map theory. Our results show that Boolean maps are the manipulation unit of working memory.

Language competency in autism: a scientometric review

The study of atypical language acquisition in children with, autism spectrum disorder (ASD) is crucial for both practical and theoretical reasons. Understanding the course of language development in ASD can inform potential interventions and treatments while shedding light on the necessary conditions for language development in typically developing children. This scientometric review aims to provide a comprehensive overview of the research landscape in this field, identifying trends, patterns, and knowledge gaps. The methods employed in this review comprise a systematic search of three major databases: Scopus (5,026 documents), Web of Science (WoS; 4,570 documents), and Lens (3,235 documents). The analysis includes bibliometric indicators such as knowledge production size by year, country, university, source, subject area, author, and citation. Scientometric indicators consist of burst detection, silhouette, clusters, citation, and co-occurrence of keywords. The analysis reveals clusters focusing on various aspects of language development in ASD, such as motor skills, parental communication strategies, cognitive processes, and genetics. Key clusters include the relationship between fine motor gestures and language usage patterns, the role of expressive language skills and maternal gesture use, and the effectiveness of online parent training modules for improving prelinguistic predictors. Other noteworthy clusters explore the importance of core language skills, the role of natural language input and syntactic complexity, and the genetic underpinnings of language abilities in high-functioning adults with ASD. In conclusion, this scientometric review highlights the top 10 clusters and their respective Silhouette values, providing valuable insights into language acquisition in ASD. These findings have important implications for guiding future research directions and informing the creation of targeted and effective interventions to support language acquisition in this population.

A Role for Visual Memory in Vocabulary Development: A Systematic Review and Meta-Analysis

Although attention and early associative learning in preverbal children is predominantly driven by rapid eye-movements in response to moving visual stimuli and sounds/words (e.g., associating the word "bottle" with the object), the literature examining the role of visual attention and memory in ongoing vocabulary development across childhood is limited. Thus, this systematic review and meta-analysis examined the association between visual memory and vocabulary development, including moderators such as age and task selection, in neurotypical children aged 2-to-12 years, from the brain-based perspective of cognitive neuroscience. Visual memory tasks were classified according to the visual characteristics of the stimuli and the neural networks known to preferentially process such information, including consideration of the distinction between the ventral visual stream (processing more static visuo-perceptual details, such as form or colour) and the more dynamic dorsal visual stream (processing spatial temporal action-driven information). Final classifications included spatio-temporal span tasks, visuo-perceptual or spatial concurrent array tasks, and executive judgment tasks. Visuo-perceptual concurrent array tasks, reliant on ventral stream processing, were moderately associated with vocabulary, while tasks measuring spatio-temporal spans, associated with dorsal stream processing, and executive judgment tasks (central executive), showed only weak correlations with vocabulary. These findings have important implications for health professionals and researchers interested in language, as they advocate for the development of more targeted language learning interventions that include specific and relevant aspects of visual processing and memory, such as ventral stream visuo-perceptual details (i.e., shape or colour).

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.

Executive Functions and Foreign Language Learning

Executive functions (EFs) serve as an umbrella term to describe a set of higher-order cognitive abilities that include working memory, inhibitory control, cognitive flexibility, planning, reasoning, and problem-solving. Various studies suggest that foreign language learning likely promotes executive functions, but others suggest that executive functions could improve foreign language learning. The aim of this study is to investigate the relationship between executive functions and foreign language learning and how these processes could interact. The sample included 64 children from kindergarten, aged 4-5 years, with no documented neuropsychiatric disorders, and from the middle-high literacy group. They were divided into three groups based on the level of their knowledge of the foreign language. A significant effect of the group on the executive tasks is shown in the comparison of the groups. Children who belonged to a group that had advanced foreign language proficiency had better results in executive tasks. Our results suggest that the higher the level of foreign language proficiency, the higher the performance of the executive tasks. However, we do not know if there is a causal effect between these variables.

Visual working memory performance is intact across development in autism spectrum disorder

Autism spectrum disorder (ASD) is associated with atypical visual processing and deficits in working memory (WM). Visual WM performance typically improves between childhood and adulthood, but such improvement may be atypical in ASD. To better understand how visual WM develops, we used a well-established change detection task across multiple visual features. We examined visual WM for color, shape, and pattern in children, adolescents, and adults with and without ASD. VWM capacity and performance for all visual features improved across age similarly for both the TD and ASD groups. While performance was better on set size 4 trials than set size 8 trials for color, shape, and no change trials, such an effect was not evident for pattern change trials. Overall, the present findings suggest that VWM for different visual features may be intact across development in ASD. The ability to hold multiple objects in mind (WM) improves across typical development, but it remains unclear whether such improvement occurs in ASD. We found that developmental improvements in WM for different types of object details (e.g., color, shape, and pattern) is generally similar for both ASD and typical development.

Assessment of theory of mind in Tunisian verbal children with autism spectrum disorder

The present study examined performance in Theory of Mind (ToM) in a group of 31 Arabic-speaking verbal children (7-12 years-old) with autism spectrum disorder (ASD), in comparison with neurotypical controls (NT) matched for age and for cognitive abilities. An innovative task in a digital format named "The Tunisian Social Situations Instrument" (TSSI) was used and allowed us to study four different subdomains of ToM: attribution of intention and epistemic ToM (cognitive ToM), affective ToM, and detection of faux pas (advanced ToM). Our study showed impairments in ToM in children with ASD, similar to those reported in the literature. Our findings additionally suggested that affective and advanced ToM, specifically the detection of faux pas, might be more challenging for ASD children than other components of ToM. Future studies with larger number of children may lead us to specify which subdomains are the most impaired in order to develop specific tools targeting these specific impairments.

Brief Report: Examining the Links Between Language Processes and Working Memory Impairments in Toddlers and Preschoolers with ASD

Deficits in working memory have not been fully explored in toddlers and preschoolers with autism spectrum disorder (ASD). We investigated the relationship between language (verbal ability, verbal self-talk) and visuospatial working memory in 2- and 4-year-olds with ASD (n = 65) and typical development (TD) (n = 54). Children with ASD displayed impairments in working memory and verbal ability, but not verbal self-talk, compared to TD peers. Verbal ability and working memory were positively correlated; this association was stronger for children with ASD. For 2-year-olds, self-talk and working memory were negatively correlated. Results suggest that verbal ability and working memory are linked, especially for young children with ASD. Self-talk may be a compensatory strategy for toddlers with less developed working memory.

Verbal mediation of theory of mind in verbal adolescents with autism spectrum disorder

This study tests the role of verbal mediation during theory of mind processing in autism spectrum disorder (ASD). Adolescents with ASD or typical development completed a false belief task while simultaneously performing a verbal or nonverbal load task. There was no group difference in false belief accuracy; however, under verbal load, the ASD group was relatively less efficient, with slower reaction times, in false belief compared to true belief trials. Faster false belief task performance under verbal but not nonverbal load was associated with pragmatic language ability for the ASD group only. Results were consistent with the theory that there are two (implicit, nonverbal and explicit, verbal) processes that support cognitive reasoning about other people's minds (Apperly & Butterfill, 2009), and that people with ASD rely more on the explicit system. Verbal mediation may be critical for false belief understanding in individuals with ASD, but not typical development.

Associations between stuttering, comorbid conditions and executive function in children: a population-based study

Background

The aim of this study was to investigate the relationship between executive function (EF), stuttering, and comorbidity by examining children who stutter (CWS) and children who do not stutter (CWNS) with and without comorbid conditions. Data from the National Health Interview Survey were used to examine behavioral manifestations of EF, such as inattention and self-regulation, in CWS and CWNS.

Methods

The sample included 2258 CWS (girls = 638, boys = 1620), and 117,725 CWNS (girls = 57,512; boys = 60,213). EF, and the presence of stuttering and comorbid conditions were based on parent report. Descriptive statistics were used to describe the distribution of stuttering and comorbidity across group and sex. Regression analyses were to determine the effects of stuttering and comorbidity on EF, and the relationship between EF and socioemotional competence.

Results

Results point to weaker EF in CWS compared to CWNS. Also, having comorbid conditions was also associated with weaker EF. CWS with comorbidity showed the weakest EF compared to CWNS with and without comorbidity, and CWS without comorbidity. Children with stronger EF showed higher socioemotional competence. A majority (60.32%) of CWS had at least one other comorbid condition in addition to stuttering. Boys who stutter were more likely to have comorbid conditions compared to girls who stutter.

Conclusion

Present findings suggest that comorbidity is a common feature in CWS. Stuttering and comorbid conditions negatively impact EF.

Comparison of Disfluent and Ungrammatical Speech of Preadolescents with and without ASD

This paper analyses disfluencies and ungrammatical expressions in the speech of 11-13-year-old Finnish-speaking boys with ASD (N = 5) and with neurotypical development (N = 6). The ASD data were from authentic group therapy sessions and neurotypical data from teacher-led group discussions. The proportion of disfluencies and ungrammatical expressions was greater in the speech of participants with ASD (26.4%) than in the control group (15.5%). Furthermore, a qualitative difference was noted: The ASD group produced long, complex disfluent turns with word searches, self-repairs, false starts, fillers, prolongations, inconsistent syntactic structures and grammatical errors, whereas in the control group, the disfluencies were mainly fillers and sound prolongations. The disfluencies and ungrammatical expressions occurring in the ASD participants' interactions also caused comprehension problems.

The Role of Inner Speech in Executive Functioning Tasks: Schizophrenia With Auditory Verbal Hallucinations and Autistic Spectrum Conditions as Case Studies

Several theories propose that one of the core functions of inner speech (IS) is to support subjects in the completion of cognitively effortful tasks, especially those involving executive functions (EF). In this paper we focus on two populations who notoriously encounter difficulties in performing EF tasks, namely, people diagnosed with schizophrenia who experience auditory verbal hallucinations (Sz-AVH) and people with autism spectrum conditions (ASC). We focus on these two populations because they represent two different ways in which IS can fail to help in EF tasks, which can be illustrative for other mental conditions. First, we review the main components of EF (see section "Executive Functions"). Then we explain the functions that IS is taken to perform in the domain of EF (see section "Inner Speech and Executive Functions") and review the evidence concerning problems about EF in the two populations of our study: Sz-AVH (see section "Executive Functions and Inner Speech in Sz-AVH") and ASC (see section "Executive Function and Inner Speech in ASC"). After this we further detail our account about what a properly functioning IS can do for both populations and how different IS profiles may impact EF performance: in the case of Sz-AVH, the uncontrolled and intrusive character of IS negatively affects EF performance, whereas in ASC, EF is not sufficiently supported by IS, given the tendency in this population to present a diminished use of IS (see section "IS in ASC and Sz-AVH: How It Relates to EF"). We finally briefly discuss Attention Deficit/Hyperactivity Disorder (ADHD) and Developmental Language Disorders (DLD) (see section "Further Considerations").

Planning in Children with Autism Spectrum Disorder: The Role of Verbal Mediation

This study examined verbal mediation during planning in school-age children with autism spectrum disorder (ASD) relative to age- and nonverbal IQ- matched typically developing peers using a dual-task paradigm. Analyses showed no group differences in performance. However, in the condition intended to disrupt verbal mediation, language skills were associated with planning performance for the TD group, but not the ASD group. Upon examining ASD subgroups with versus without comorbid structural language impairment, children with ASD and normal language appeared to rely on verbal mediation to a greater degree than children with ASD and language impairment, but to a lesser degree than TD peers. Thus, the role of verbal mediation in planning for children with ASD differs depending on language status.

Cognitive and Affective Aspects of Theory of Mind in Greek-Speaking Children with Autism Spectrum Disorders

Substantial research indicates that individuals with Autism Spectrum Disorder (ASD) have difficulties with Theory of Mind (ToM) abilities, but rarely have studies used a comprehensive battery to measure both the cognitive and affective aspects of ToM. The present study tested this ability in 24 Greek-speaking children with ASD (ages 7-14), and their performance was compared to 24 age-, gender- and language-matched typically developing controls. Results showed that ASD children's performance was selectively impaired in both ToM aspects, supporting the distinction between ToM components. This is the first study of ToM abilities among Greek-speaking children with ASD, and the findings confirm that children with ASD are experiencing difficulties with socio-emotional understanding across languages and cultures.

A Review of Language, Executive Function, and Intervention in Autism Spectrum Disorder

Difficulties with both executive functions and language skills are common but variable in autism spectrum disorder (ASD). Executive functions and language skills are related to one another, such that vocabulary, syntax, and pragmatics are related to domains of working memory, shifting, and inhibition in ASD, although the directionality of these relationships remains unclear. Moreover, interventions that target pragmatic ability have been found to improve executive function skills, and conversely, executive function interventions are linked with improvements in social skills in children with ASD. We review the literature on executive functions, language skills, and their relationship in ASD; discuss factors that may be driving inconsistent findings; and explore clinical applications from the research thus far.

Ungrammatical utterances and disfluent speech as causes of comprehension problems in interactions of preadolescents with high functioning autism

This study describes the role of ungrammatical utterances and disfluent speech in the creation of comprehension problems between the participants in group therapy sessions of preadolescents with autism. The speech of the autistic preadolescents included frequent disfluencies and morpho-syntactic problems, such as wrong case endings, ambiguous pronominal references, grammatically incoherent syntactic structures and inaccurate tenses, which caused problems of comprehension. Three different interactional trajectories occurred when solving the potential problems of comprehension following the morpho-syntactically disfluent turns. First, the disfluent turn sometimes led to a clarification request by a co-participant, either a therapist or another participant with ASD. The preadolescents with ASD showed interactional skilfulness in requesting clarification when faced with comprehension problems. Second, in contrast, other occurrences included one or several self-repairs by the speaker with ASD. In these cases, the other group participants either did not react or they encouraged the speaker to continue using discourse particles. If the self-repairing disfluencies led to a persisting problem of comprehension, the therapists sometimes intervened and resolved the problem. However, direct interventions by the therapists were infrequent because the participants with ASD were mostly able to resolve the comprehension problems by themselves. Third, some disfluent and/or grammatically incorrect turns were not treated as problematic by the co-participants nor by the speaker himself. Abbreviations: ADE: Adessive; ALL: Allative; CLI: clitic; GEN: Genitive; INE: Inessive; NOM: Nominative; PER: person; PL: plural; PRT: particle; SG: singular.

Executive Function Skills in School-Age Children With Autism Spectrum Disorder: Association With Language Abilities

PURPOSE

This article reviews research on executive function (EF) skills in children with autism spectrum disorder (ASD) and the relation between EF and language abilities. The current study assessed EF using nonverbal tasks of inhibition, shifting, and updating of working memory (WM) in school-age children with ASD. It also evaluated the association between children's receptive and expressive language abilities and EF performance.

METHOD

In this study, we sought to address variables that have contributed to inconsistencies in this area of research-including task issues, group comparisons, and participant heterogeneity. EF abilities in children with ASD (n = 48) were compared to typically developing controls (n = 71) matched on age, as well as when statistically controlling for group differences in nonverbal cognition, socioeconomic status, and social communication abilities. Six nonverbal EF tasks were administered-2 each to evaluate inhibition, shifting, and WM. Language abilities were assessed via a standardized language measure. Language-EF associations were examined for the ASD group as a whole and subdivided by language status.

RESULTS

Children with ASD exhibited significant deficits in all components of EF compared to age-mates and showed particular difficulty with shifting after accounting for group differences in nonverbal cognition. Controlling for social communication-a core deficit in ASD-eliminated group differences in EF performance. A modest association was observed between language (especially comprehension) and EF skills, with some evidence of different patterns between children on the autism spectrum with and without language impairment.

CONCLUSIONS

There is a need for future research to examine the direction of influence between EF and language. It would be beneficial for EF interventions with children with ASD to consider language outcomes and, conversely, to examine whether specific language training facilitates aspects of executive control in children on the autism spectrum.

PRESENTATION VIDEO

https://doi.org/10.23641/asha.7298144.

Impaired nonverbal working memory in high-functioning autism spectrum disorder

Background: Past studies have documented working memory impairment in participants with high-functioning Autism Spectrum Disorders (IQ>70), but inconsistent findings have been reported. One possibility is the existence of verbal responses in the evaluation of working memory performance. The aim of the current study is to examine the working memory performance and its correlation with a prominent deficit in participants with high-functioning Autism Spectrum Disorders by non-verbal working memory tasks compared with typically developing samples.

Methods: The current study is a cross-sectional, comparative study. The working memory performance of the 30 participants with high-functioning Autism Spectrum Disorders (7-16 years) and 30 typically developing was compared by working memory subtests of the Leiter International Performance Scale-Revised in Tehran, Iran. Two groups were matched for age and gender. ANOVA, ANCOVA, repeated measures ANOVA and Pearson’s correlation coefficient were used to analyze the data statistically. The significance value was set at p<0.05.

Results: The results showed that if the effect of FSIQ (full-scale intelligence quotient) were controlled individuals with highfunctioning Autism Spectrum Disorders exhibited significant impairment in the Reverse Memory subtest (p=0.001). Also, unpredictably Forward Memory (r=0.38, p=0.03) and Reverse Memory tasks (r=0.38, p=0.03) displayed a significant positive correlation with the Social interaction subscale of the Gilliam Autism Rating Scale (Second Edition).

Conclusion: It seems that nonverbal working memory is impaired in persons with high-functioning Autism Spectrum Disorders. Results of the current study revealed that factors like complexity and cognitive load of tasks may influence working memory performance in individuals with high-functioning Autism Spectrum Disorders.

Reading Comprehension in Children With and Without ASD: The Role of Word Reading, Oral Language, and Working Memory

Word reading and oral language predict reading comprehension, which is generally poor, in individuals with autism spectrum disorder (ASD). However, working memory (WM), despite documented weaknesses, has not been thoroughly investigated as a predictor of reading comprehension in ASD. This study examined the role of three parallel WM N-back tasks using abstract shapes, familiar objects, and written words in children (8-14 years) with ASD (n = 19) and their typically developing peers (n = 24). All three types of WM were significant predictors of reading comprehension when considered alone. However, these relationships were rendered non-significant with the addition of age, word reading, vocabulary, and group entered into the models. Oral vocabulary emerged as the strongest predictor of reading comprehension.

Computerized Cognitive Training in Children With Autism and Intellectual Disabilities: Feasibility and Satisfaction Study

BACKGROUND

Researchers are increasingly interested in testing and developing computerized cognitive training interventions for individuals with autism spectrum disorder due to the limited accessibility of treatments for this disorder. Understanding the feasibility of testing cognitive interventions for this population is critical, especially for individuals with ASD who have low to moderate intellectual ability.

OBJECTIVE

The aim of the study was to evaluate the feasibility of computerized cognitive training as measured by attrition rate and a parent satisfaction survey.

METHODS

A total of 26 participants aged 8-17 years with an autism spectrum disorder diagnosis and significant intellectual impairment were enrolled (mean age 11.1 years). They were instructed to complete 25 sessions of Cogmed Working Memory Training in 5 to 6 weeks with coach assistance. Attrition rate and parent satisfaction surveys were measured after the completion of training.

RESULTS

Most participants (96%, 25/26) completed the training and indicated high satisfaction (>88%). However, among the participants who completed the training, 5 participants (19%) were unable to finish in 6 weeks, the recommended training period by Cogmed. Parents noted various positive (eg, voice-overs) and negative (eg, particular graphic and sounds associated with a stimulus) features of the game that they thought affected their child's response.

CONCLUSIONS

Children with autism spectrum disorder and intellectual impairments can successfully participate in computerized cognitive training interventions but may require additional weeks to complete the training beyond the time needed for children without intellectual impairments. The overall completion rate, with extended time to complete the training, was high. Developers of cognitive training programs for this population should take into account potential issues regarding the noise level of stimuli and characteristics of the visual graphics.

The Role of Language in Nonlinguistic Stimuli: Comparing Inhibition in Children With Language Impairment

PURPOSE

There is conflicting evidence regarding if and how a deficit in executive function may be associated with developmental language impairment (LI). Nonlinguistic stimuli are now frequently used when testing executive function to avoid a language confound. However, it is possible that increased stimulus processing demands for nonlinguistic stimuli may also compound the complexity of the relationship between executive function and LI. The current study examined whether variability across nonlinguistic auditory stimuli might differentially affect inhibition and whether performance differs between children with and without language difficulties.

METHOD

Sixty children, aged 8-14 years, took part in the study: 20 typically developing children, 20 children with autism spectrum disorder, and 20 children with specific LI. For the purposes of assessing the role of language, children were further categorized based on language ability: 33 children with normal-language (NL) ability and 27 children with LI. Children completed a go/no-go task with 2 conditions comparing nonlinguistic auditory stimuli: 2 abstract sounds and 2 familiar sounds (duck quack and dog bark).

RESULTS

There was no significant difference for diagnostic category. However, there was a significant interaction between language ability and condition. There was no significant difference in the NL group performance in the abstract and familiar sound conditions. In contrast, the group with LI made significantly more errors in the abstract condition compared with the familiar condition. There was no significant difference in inhibition between the NL group and the group with LI in the familiar condition; however, the group with LI made significantly more errors than the NL group in the abstract condition.

CONCLUSIONS

Caution is needed in stimuli selection when examining executive function skills because, although stimuli may be selected on the basis of being "nonlinguistic and auditory," the type of stimuli chosen can differentially affect performance. The findings have implications for the interpretation of deficits in executive function as well as the selection of stimuli in future studies.

Executive Functions and Prosodic Abilities in Children With High-Functioning Autism

Little is known about the relationship between prosodic abilities and executive function skills. As deficits in executive functions (EFs) and prosodic impairments are characteristics of autism, we examined how EFs are related to prosodic performance in children with high-functioning autism (HFA). Fifteen children with HFA (M = 7.4 years; SD = 1.12), matched to 15 typically developing peers on age, gender, and non-verbal intelligence participated in the study. The Profiling Elements of Prosody in Speech-Communication (PEPS-C) was used to assess prosodic performance. The Children's Color Trails Test (CCTT-1, CCTT-2, and CCTT Interference Index) was used as an indicator of executive control abilities. Our findings suggest no relation between prosodic abilities and visual search and processing speed (assessed by CCTT-1), but a significant link between prosodic skills and divided attention, working memory/sequencing, set-switching, and inhibition (assessed by CCTT-2 and CCTT Interference Index). These findings may be of clinical relevance since difficulties in EFs and prosodic deficits are characteristic of many neurodevelopmental disorders. Future studies are needed to further investigate the nature of the relationship between impaired prosody and executive (dys)function.

Metacognitive Aspects of Executive Function Are Highly Associated with Social Functioning on Parent-Rated Measures in Children with Autism Spectrum Disorder

Autism Spectrum Disorder (ASD) is characterized by social dysfunction. Even though executive dysfunction has been recognized as important in understanding ASD, the findings are inconsistent. This might be due to different definitions of executive function (EF), which part of EF that has been studied, structured vs. unstructured tasks, inclusion of different moderators (age, IQ, sex) and different diagnostic categories within the spectrum. The main finding is that people with ASD have more EF difficulties than normal controls and more difficulties on open-end tasks than on structured cognitive tasks. Since some EF difficulties may not be observable in a laboratory setting, informant measures might have higher ecological validity than neuropsychological tests. Evidence suggests that executive dysfunctions are associated with social impairments, but few studies have investigated the details of this relationship, and it remains unclear what types of EF deficits are relevant for the social problems of individuals with ASD. Here we investigated which EF domains were associated with various domains of social function on parent-rated measures. A total of 86 children and adolescents with a diagnosis of ASD were included and tested for general cognitive abilities. Parents completed the Behavior Rating Inventory of Executive Function (BRIEF) and the Social Responsiveness Scale (SRS). Multiple regression analysis revealed significant associations between SRS scores and age, sex, total IQ and the BRIEF indexes. The Metacognition Index from the BRIEF added significantly to the prediction of the SRS total score and the subscales Social Communication, Social Motivation and Autistic Mannerisms. The findings suggest that metacognitive aspects of EF are of particular importance for social abilities in children and adolescents with ASD. Earlier research has shown that typically developing (TD) children have a different relationship between EF and social function than children with ASD. They found that in TD children the EF domain related to behavioral regulation was most important to social function. The results from the current study may have implications for understanding the cognitive components of the social problems that define ASD, and may be relevant in developing more targeted clinical EF interventions related to core ASD dysfunctions.

Subtyping cognitive profiles in Autism Spectrum Disorder using a Functional Random Forest algorithm

DSM-5 Autism Spectrum Disorder (ASD) comprises a set of neurodevelopmental disorders characterized by deficits in social communication and interaction and repetitive behaviors or restricted interests, and may both affect and be affected by multiple cognitive mechanisms. This study attempts to identify and characterize cognitive subtypes within the ASD population using our Functional Random Forest (FRF) machine learning classification model. This model trained a traditional random forest model on measures from seven tasks that reflect multiple levels of information processing. 47 ASD diagnosed and 58 typically developing (TD) children between the ages of 9 and 13 participated in this study. Our RF model was 72.7% accurate, with 80.7% specificity and 63.1% sensitivity. Using the random forest model, the FRF then measures the proximity of each subject to every other subject, generating a distance matrix between participants. This matrix is then used in a community detection algorithm to identify subgroups within the ASD and TD groups, and revealed 3 ASD and 4 TD putative subgroups with unique behavioral profiles. We then examined differences in functional brain systems between diagnostic groups and putative subgroups using resting-state functional connectivity magnetic resonance imaging (rsfcMRI). Chi-square tests revealed a significantly greater number of between group differences (p < .05) within the cingulo-opercular, visual, and default systems as well as differences in inter-system connections in the somato-motor, dorsal attention, and subcortical systems. Many of these differences were primarily driven by specific subgroups suggesting that our method could potentially parse the variation in brain mechanisms affected by ASD.

The Comprehension of Syntactic and Affective Prosody by Adults with Autism Spectrum Disorder Without Accompanying Cognitive Deficits

The present study investigates the comprehension of syntactic and affective prosody in adults with autism spectrum disorder without accompanying cognitive deficits (ASD w/o cognitive deficits) as well as age-, education- and gender-matched unimpaired adults, while processing orally presented sentences. Two experiments were conducted: (a) an on-line sentence completion task containing local subject/object ambiguities and (b) an affective prosody task exploring the comprehension of six emotions. The syntactic prosody task revealed that the experimental group performed similar to the control group on the fillers and the object condition. On the other hand, the ASD w/o cognitive deficits group manifested lower accuracy compared to the unimpaired controls in the subject reading condition, as well as slower reaction times in all conditions. In the affective prosody task, the experimental group performed significantly worse than the controls in the recognition of the emotion of surprise, whereas no differences between the experimental and the control group were attested in the recognition of all other emotions. A positive correlation was found between the two tasks in the ASD w/o cognitive deficits group. Thus, individuals with ASD w/o cognitive deficits face slight difficulties with the decoding of prosody, both the syntactic and the affective one. More specifically, these difficulties are attested in the most difficult conditions, i.e. the subject reading and the emotion of surprise.

Executive functioning in Cornelia de Lange syndrome: domain asynchrony and age-related performance

BACKGROUND

The aim of this study was to examine executive functioning in adolescents and adults with Cornelia de Lange syndrome (CdLS) to identify a syndrome and age-related profile of cognitive impairment.

METHODS

Participants were 24 individuals with CdLS aged 13-42 years (M = 22; SD = 8.98), and a comparable contrast group of 21 individuals with Down syndrome (DS) aged 15-33 years (M = 24; SD = 5.82). Measures were selected to test verbal and visual fluency, inhibition, perseverance/flexibility, and working memory and comprised both questionnaire and performance tests.

RESULTS

Individuals with CdLS showed significantly greater impairment on tasks requiring flexibility and inhibition (rule switch) and on forwards span capacity. These impairments were also reported in the parent/carer-rated questionnaire measures. Backwards Digit Span was significantly negatively correlated with chronological age in CdLS, indicating increased deficits with age. This was not identified in individuals with DS.

CONCLUSIONS

The relative deficits in executive functioning task performance are important in understanding the behavioural phenotype of CdLS. Prospective longitudinal follow-up is required to examine further the changes in executive functioning with age and if these map onto observed changes in behaviour in CdLS. Links with recent research indicating heightened responses to oxidative stress in CdLS may also be important.

Balanced bifrontal transcranial direct current stimulation enhances working memory in adults with high-functioning autism: a sham-controlled crossover study

Background

Working memory (WM) often is impaired in autism spectrum disorder (ASD). Such impairment may underlie core deficits in cognition and social functioning. Transcranial direct current stimulation (tDCS) has been shown to enhance WM in both healthy adults and clinical populations, but its efficacy in ASD is unknown. We predicted that bifrontal tDCS would improve WM performances of adults with high-functioning autism during active stimulation compared to sham stimulation and that such enhancement would generalize to an untrained task.

Methods

Twelve adults with high-functioning ASD engaged in a battery of WM tasks that included backward spatial span, backward digit span, spatial n-back and letter n-back. While engaged, 40 min of 1.5 mA bifrontal stimulation was applied over the left and the right dorsolateral prefrontal cortices (DLPFC). Using a single-blind crossover design, each participant received left anodal/right cathodal stimulation, right anodal/left cathodal stimulation, or sham stimulation, in randomized counterbalanced order on three separate days. Following tDCS, participants again engaged in letter and spatial n-back tasks before taking the Brief Test of Attention (BTA). We used repeated-measures ANOVA to compare overall performance on the WM battery as measured by a composite of z-scores for all five measures. Post hoc ANOVAs, t tests, Friedman’s tests, and Wilcoxon signed-rank tests were used to measure the online and offline effects of tDCS and to assess performances on individual measures.

Results

Compared to sham stimulation, both left DLPFC anodal stimulation (t₁₁ = 5.4, p = 0.0002) and right DLPFC anodal stimulation (t₁₁ = 3.57, p = 0.004) improved overall WM performance. Left anodal stimulation (t₁₁ = 3.9, p = 0.003) and right anodal stimulation (t₁₁ = 2.7, p = 0.019) enhanced performances during stimulation. Enhancement transferred to an untrained task 50 min after right anodal stimulation (z₁₁ = 2.263, p = 0.024). The tasks that showed the largest effects of active stimulation were spatial span backward (z₁₁ = 2.39, p = 0.017) and BTA (z₁₁ = 2.263, p = 0.024).

Conclusions

In adults with high-functioning ASD, active bifrontal tDCS given during WM tasks appears to improve performance. TDCS benefits also transferred to an untrained task completed shortly after stimulation. These results suggest that tDCS can improve WM task performance and could reduce some core deficits of autism.

Trial registration

NCT01602263

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.

The Relationship Between Executive Functions and Language Abilities in Children: A Latent Variables Approach

Purpose

We aimed to outline the latent variables approach for measuring nonverbal executive function (EF) skills in school-age children, and to examine the relationship between nonverbal EF skills and language performance in this age group.

Method

Seventy-one typically developing children, ages 8 through 11, participated in the study. Three EF components, inhibition, updating, and task-shifting, were each indexed using 2 nonverbal tasks. A latent variables approach was used to extract latent scores that represented each EF construct. Children were also administered common standardized language measures. Multiple regression analyses were conducted to examine the relationship between EF and language skills.

Results

Nonverbal updating was associated with the Receptive Language Index on the Clinical Evaluation of Language Fundamentals-Fourth Edition (CELF-4). When composites denoting lexical-semantic and syntactic abilities were derived, nonverbal inhibition (but not shifting or updating) was found to predict children's syntactic abilities. These relationships held when the effects of age, IQ, and socioeconomic status were controlled.

Conclusions

The study makes a methodological contribution by explicating a method by which researchers can use the latent variables approach when measuring EF performance in school-age children. The study makes a theoretical and a clinical contribution by suggesting that language performance may be related to domain-general EFs.

Planning Skills in Autism Spectrum Disorder Across the Lifespan: A Meta-analysis and Meta-regression

Individuals with an autism spectrum disorder (ASD) are thought to encounter planning difficulties, but experimental research regarding the mastery of planning in ASD is inconsistent. By means of a meta-analysis of 50 planning studies with a combined sample size of 1755 individuals with and 1642 without ASD, we aim to determine whether planning difficulties do exist and which factors contribute to this. Planning problems were evident in individuals with ASD (Hedges'g = 0.52), even when taking publication bias into account (Hedges'g = 0.37). Neither age, nor task-type, nor IQ reduced the observed heterogeneity, suggesting that these were not crucial moderators within the current meta-analysis. However, while we showed that ASD individuals encounter planning difficulties, the bias towards publishing positive findings restricts strong conclusions regarding the role of potential moderators.

Nonverbal short-term serial order memory in autism spectrum disorder

To clarify the role of item and order memory in the serial recall of adults with autism spectrum disorder (ASD), we carried out 2 experiments in which adults with ASD and comparison participants matched on chronological age and verbal IQ saw sequences of 7 dots appear sequentially in a 3 × 4 grid. In Experiment 1 (serial recall), they had to recall the locations and the presentation order of the dots by tapping locations on an empty grid. In Experiment 2, (order reconstruction) the studied dots were provided at test and participants had to touch them in their order of appearance at study. Experiment 1 revealed diminished item and order recall in the ASD group; Experiment 2 revealed diminished order recall only when verbal IQ was controlled. The results support the view that people with ASD have particular difficulty with serial order recall but may use their language ability to achieve better serial recall performance.

When asked to recall a sequence of dot locations in order, adults with autism spectrum disorder (ASD) make more errors in recalling the order of the locations than do matched typical individuals. This difficulty is less evident when the dot locations are provided at test, and participants simply have to reconstruct the order in which they originally appeared. Together with parallel findings using verbal material, there appears to be a general (cross-domain) deficit in order processing in individuals with a diagnosis of ASD. There is also some evidence that the ASD participants relied on language capability to accomplish this nonverbal task.

The Use of Linguistic Cues in Sentence Comprehension by Mandarin-Speaking Children with High-Functioning Autism

Two studies were conducted to investigate how high-functioning children with autism use different linguistic cues in sentence comprehension. Two types of linguistic cues were investigated: word order and morphosyntactic cues. The results show that children with autism can use both types of cues in sentence comprehension. However, compared to age-matched typically developing peers, children with autism relied significantly more on word order cues and exhibited significantly more difficulties in interpreting sentences in which there was a conflict between the morphosyntactic cue and the word order cue. We attribute the difficulties exhibited by children with autism to their deficits in executive function. We then discuss the implications of the findings for understanding the nature of the sentence processing mechanism in autism.

Verbal Thinking and Inner Speech Use in Autism Spectrum Disorder

The extent to which cognition is verbally mediated in neurotypical individuals is the subject of debate in cognitive neuropsychology, as well as philosophy and psychology. Studying "verbal thinking" in developmental/neuropsychological disorders provides a valuable opportunity to inform theory building, as well as clinical practice. In this paper, we provide a comprehensive, critical review of such studies among individuals with autism spectrum disorder (ASD). ASD involves severe social-communication deficits and limitations in cognitive/behavioural flexibility. The prevailing view in the field is that neither cognition nor behaviour is mediated verbally in ASD, and that this contributes to diagnostic features. However, our review suggests that, on the contrary, most studies to date actually find that among people with ASD cognitive task performance is either a) mediated verbally in a typical fashion, or b) not mediated verbally, but at no obvious cost to overall task performance. Overall though, these studies have methodological limitations and thus clear-cut conclusions are not possible at this stage. The aim of the review is to take stock of existing empirical findings, as well as to help develop the directions for future research that will resolve the many outstanding issues in this field.

Semantic Verbal Fluency in Children with and without Autism Spectrum Disorder: Relationship with Chronological Age and IQ

We administered a semantic verbal fluency (SVF) task to two groups of children (age range from 5 to 8): 47 diagnosed with Autism Spectrum Disorder (ASD Group) and 53 with typical development (Comparison Group), matched on gender, chronological age, and non-verbal IQ. Four specific indexes were calculated from the SVF task, reflecting the different underlying cognitive strategies used: clustering (component of generativity and lexical-semantic access), and switching (executive component, cognitive flexibility). First, we compared the performance of the two groups on the different SVF task indicators, with the ASD group scoring lower than the Comparison Group, although the difference was greater on switching than on clustering. Second, we analyzed the relationships between the different SVF measures and chronological age, verbal IQ and non-verbal IQ. While in the Comparison Group chronological age was the main predictor of performance on the SVF task, in the ASD Group verbal IQ was the best predictor. In the children with ASD, therefore, greater linguistic competence would be associated with better performance on the SVF task, which should be taken into account in speech therapies designed to achieve improvements in linguistic generativity and cognitive flexibility.

Deficits in executive functions among youths with autism spectrum disorders: an age-stratified analysis

BACKGROUND

Impaired executive function (EF) is suggested to be one of the core features in individuals with autism spectrum disorders (ASD); however, little is known about whether the extent of worse EF in ASD than typically developing (TD) controls is age-dependent. We used age-stratified analysis to reveal this issue.

METHOD

We assessed 111 youths with ASD (aged 12.5 ± 2.8 years, male 94.6%) and 114 age-, and sex-matched TD controls with Digit Span and four EF tasks of the Cambridge Neuropsychological Test Automated Battery (CANTAB): Spatial Span (SSP), Spatial Working Memory (SWM), Stockings of Cambridge (SOC), and Intradimensional/Extradimensional Shift Test (I/ED).

RESULTS

Compared to TD controls, youths with ASD performed poorer on the Digit Span, SWM, SOC, and I/ED tasks. The performance of all the tasks improved with age for both groups. Age-stratified analyses were conducted due to significant age × group interactions in visuospatial planning (SOC) and set-shifting (I/ED) and showed that poorer performance on these two tasks in ASD than TD controls was found only in the child (aged 8-12 years) rather than the adolescent (aged 13-18 years) group. By contrast, youths with ASD had impaired working memory, regardless of age. The increased magnitude of group difference in visuospatial planning (SOC) with increased task demands differed between the two age groups but no age moderating effect on spatial working memory.

CONCLUSIONS

Our findings support deficits in visuospatial working memory and planning in youths with ASD; however, worse performance in set-shifting may only be demonstrated in children with ASD.

Measuring the development of inhibitory control: The challenge of heterotypic continuity

Inhibitory control is thought to demonstrate heterotypic continuity, in other words, continuity in its purpose or function but changes in its behavioral manifestation over time. This creates major methodological challenges for studying the development of inhibitory control in childhood including construct validity, developmental appropriateness and sensitivity of measures, and longitudinal factorial invariance. We meta-analyzed 198 studies using measures of inhibitory control, a key aspect of self-regulation, to estimate age ranges of usefulness for each measure. The inhibitory control measures showed limited age ranges of usefulness owing to ceiling/floor effects. Tasks were useful, on average, for a developmental span of less than 3 years. This suggests that measuring inhibitory control over longer spans of development may require use of different measures at different time points, seeking to measure heterotypic continuity. We suggest ways to study the development of inhibitory control, with overlapping measurement in a structural equation modeling framework and tests of longitudinal factorial or measurement invariance. However, as valuable as this would be for the area, we also point out that establishing longitudinal factorial invariance is neither sufficient nor necessary for examining developmental change. Any study of developmental change should be guided by theory and construct validity, aiming toward a better empirical and theoretical approach to the selection and combination of measures.

Executive function predicts the development of play skills for verbal preschoolers with autism spectrum disorders

Executive function and play skills develop in early childhood and are linked to cognitive and language ability. The present study examined these abilities longitudinally in two groups with autism spectrum disorder-a group with higher initial language (n = 30) and a group with lower initial language ability (n = 36). Among the lower language group, concurrent nonverbal cognitive ability contributed most to individual differences in executive function and play skills. For the higher language group, executive function during preschool significantly predicted play ability at age 6 over and above intelligence, but early play did not predict later executive function. These results suggested that factors related to the development of play and executive function differ for subgroups of children with different language abilities and that early executive function skills may be critical in order for verbal children with autism to develop play. Autism Res 2016, 9: 1274-1284. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

Lexical Processing in School-Age Children with Autism Spectrum Disorder and Children with Specific Language Impairment: The Role of Semantics

Children with autism spectrum disorder (ASD) and specific language impairment (SLI) often have immature lexical-semantic knowledge; however, the organization of lexical-semantic knowledge is poorly understood. This study examined lexical processing in school-age children with ASD, SLI, and typical development, who were matched on receptive vocabulary. Children completed a lexical decision task, involving words with high and low semantic network sizes and nonwords. Children also completed nonverbal updating and shifting tasks. Children responded more accurately to words from high than from low semantic networks; however, follow-up analyses identified weaker semantic network effects in the SLI group. Additionally, updating and shifting abilities predicted lexical processing, demonstrating similarity in the mechanisms which underlie semantic processing in children with ASD, SLI, and typical development.

The role of language ability and self-regulation in the development of inattentive-hyperactive behavior problems

Previous research has found associations but not established mechanisms of developmental linkage between language ability and inattentive-hyperactive (I-H) behavior problems. The present study examined whether self-regulation mediates the effect of language ability on later I-H behavior problems among young children (N = 120) assessed at 30, 36, and 42 months of age. Cross-lagged panel models tested the direction of effect between language ability and self-regulation and longitudinal effects of language ability on later I-H problems mediated by self-regulation. Language ability was measured by children's scores on the receptive and expressive language subtests of the Differential Ability Scales. Self-regulation was measured by three behavioral tasks requiring inhibitory control. I-H problems were reported by parents and secondary caregivers. Language ability predicted later self-regulation as measured by all three tasks. There was no association, however, between self-regulation and later language ability, suggesting that the direction of effect was stronger from language ability to later self-regulation. Moreover, the effect of language ability on later I-H behavior problems was mediated by children's self-regulation in one of the tasks (for secondary caregivers' but not parents' ratings). Findings suggest that language deficits may explain later I-H behavior problems via their prediction of poorer self-regulatory skills.

Reduced delay of gratification and effortful control among young children with autism spectrum disorders

We explored internal control of behavior using direct observation and parent report. Previous research has found that both the delay of gratification task and parent-reported effortful control predict later social ability and more positive outcomes in typically developing children. Children with autism spectrum disorder have previously been reported to have reduced effortful control, whereas delay of gratification ability has not been tested in a group with autism spectrum disorder. The current study compared 21 children with autism spectrum disorder and 21 typically developing children between 6 and 7 years of age-all of whom had cognitive ability at or above the average range. Children with autism spectrum disorder were less able to delay gratification, and their parents reported significantly reduced effortful control; however, scores on these measures were unrelated within the group with autism spectrum disorder. Among the children with autism spectrum disorder, lower effortful control was associated with more severe clinician-observed social symptoms.