To Typically Developing Research Articles

Altered functional connectivity of unimodal sensory and multisensory integration networks is related to symptom severity in autism spectrum disorders

BackgroundAtypical sensory processing is a prevalent feature in autism spectrum disorders (ASD) and constitutes a core diagnostic criterion in the Diagnostic and Statistical Manual of Mental of Disorders, 5th edition (DSM-5). However, neurocognitive underpinnings of atypical unimodal and multimodal sensory processing and their relationships with autism symptoms remain unclear. MethodsThis study examined intrinsic functional connectivity (FC) patterns among five unimodal sensory and multisensory integration (MSI) networks in ASD with a large multi-site dataset (n = 646), and investigated the relationships among altered FC, atypical sensory processing, social communicative deficits, and overall autism symptoms with correlation and mediation analyses. ResultsRelative to typically developing (TD) controls, the ASD group demonstrated increased FC of the olfactory network, decreased FC within the MSI network, and decreased FC of the MSI-unimodal-sensory networks. Furthermore, altered FC was positively associated with autism symptom severity, and such associations were completely mediated by atypical sensory processing and social communicative deficits. ConclusionsASD-specific olfactory overconnectivity and MSI-unimodal-sensory underconnectivity lend support to the Intense World Theory and Weak Central Coherence Theory, suggesting olfactory hypersensitivity at the expense of multisensory integration as potential neural mechanisms underlying atypical sensory processing in ASD. These atypical FC patterns further suggest potential targets for psychological and neuromodulatory interventions.

Differential Neural Mechanisms of Feedback Processing in Children with Developmental Language Disorder: An Examination of Midfrontal Theta Connectivity.

Previous research indicates that children with Developmental Language Disorder (DLD) face challenges learning from feedback, resulting in suboptimal performance and learning outcomes. Feedback processing, a key developing executive function, involves cognitive processes critical for goal-directed behavior. This study examined the neural mechanisms underlying feedback processing in school-age children with DLD compared to typically developing (TD) peers, focusing on midfrontal theta band (4-8 Hz) oscillations as an index of cognitive control and error monitoring. We measured midfrontal theta inter-trial coherence (ITC) and inter-site coherence (ISC) at midfrontal (FCz), lateral prefrontal (F3/F4), and lateral central (C3/C4) sites in children with and without DLD (n = 33, age 8-13 years) in response to feedback provision within a Wisconsin Card Sorting Test (WCST) in two time windows (200-400 ms, which is associated with the Feedback-Related Negativity, or FRN, and 400-600 ms, which is associated with the P3a). Children with and without DLD showed elevated midfrontal theta oscillations in response to negative feedback that was followed by successful behavioral adjustments in the FRN time window. Activation in the P3a time window was only found in the TD group. Group differences were also noted in the inter-site coherence (ISC) associated with the effective processing of negative feedback. While in the TD group, effective processing of negative feedback was linked to high connectivity between midfrontal and right sensorimotor regions, in the DLD group, effective processing of negative feedback was associated with high connectivity between midfrontal and left sensorimotor sites. Differential ISC patterns in children with DLD may indicate that they employ alternative or compensatory neural strategies, possibly due to atypical right sensorimotor engagement.

Strategies for unplanned gait termination at comfortable and fast walking speeds in children with cerebral palsy

Collision avoidance while walking is necessary for safe living, and faster walking speeds tend to increase collision risk. However, gait termination strategies for patients with cerebral palsy (CP), from comfortable to faster speed, remain unexplored. This study aimed to analyze these strategies in children with CP compared to typically developing (TD) children at two different speeds. Study participants included 10 children with CP (mean age, 12.5; five females; mean height, 147.8 cm; mean weight, 41.7 kg) and 10 TD children (mean age, 11.4; nine females; mean height, 142.0 cm; mean weight, 38.1 kg). Effects of walking speed on spatial, force, and temporal parameters were assessed at 100 % (WS1) and 125 % (WS2) speeds of comfortable walking. The TD group exerted a more pronounced braking force at the first step after the stop line appeared on the floor until the contralateral step at both WS1 (P = 0.006) and WS2 (P = 0.019); however, the CP group exerted a more potent force after the second step (WS1: P = 0.026, WS2: P = 0.023) in the anterior-posterior (AP) direction. Additionally, an increase in the center of mass (COM)-center of pressure (COP) divergence in the AP direction (P = 0.032), which decreased in the mediolateral (ML) direction (P = 0.036) at faster walking speeds, influenced the kinetic characteristics of the CP group from WS1 to WS2. The complex adaptations, such as unique braking forces and changes in the COM-COP divergence, suggest that gait interventions should consider the distinctive forces and adopt dynamic balancing strategies to avoid collisions during walking.

Variability of theory of mind versus pragmatic ability in typical and atypical development

IntroductionNumerous studies have linked deficits in Theory of Mind (ToM) with language problems. We aimed to explore the similarities and differences between children's patterns of performance on a ToM task that requires minimal linguistic skill and a pragmatic inference task that relies on both ToM and language. We assessed variability in pragmatic inference skills and ToM across populations of children (8–14 years) displaying varying cognitive profiles. We further compared the sensitivity of ToM versus pragmatic ability to core language skills, memory and executive functioning (EF). MethodToM was tested using the Social Attribution Task (SAT-MC-II). Pragmatic ability was assessed in an implicature comprehension task. Receptive vocabulary, grammar comprehension, short-term and working memory (STM and WM) capacity and EF were measured using Hungarian adaptations of standard tasks and tests developed by the authors’ lab. In addition to typically developing (TD) children (n = 33), we included children with neurodevelopmental disorders where ToM and/or language abilities are vulnerable: autism spectrum disorder (ASD, n = 26), attention deficit hyperactivity disorder (ADHD, n = 25) and developmental language disorder (DLD, n = 18). ResultsResults revealed a significant but only moderate positive correlation between pragmatic inference and ToM indicating that the two abilities are related but distinct. The ASD group showed impairments in both ToM and pragmatic inference ability but no significant deficit was observed in ADHD or DLD relative to TD children in either skill. However, while SAT-MC-II results were only affected by verbal WM and vocabulary measures, pragmatic performance was associated with STM, verbal WM, EF, grammatical skills and vocabulary. ConclusionOur findings indicate that disentangling the contributions of different cognitive skills to ToM tasks may help clarify the role of ToM in language skills and identify distinct patterns of ToM and pragmatic skills in developmental disorders.

The role of social motivation in sharing and fairness: insights from Williams syndrome

BackgroundSharing and fairness are important prosocial behaviors that help us navigate the social world. However, little is known about how and whether individuals with Williams Syndrome (WS) engage in these behaviors. The unique phenotype of individuals with WS, consisting of high social motivation and limited social cognition, can also offer insight into the role of social motivation in sharing and fairness when compared to typically developing (TD) individuals. The current study used established experimental paradigms to examine sharing and fairness in individuals with WS and TD individuals.MethodsWe compared a sample of patients with WS to TD children (6-year-olds) matched by mental age (MA) on two experimental tasks: the Dictator Game (DG, Experiment 1, N = 17 WS, 20 TD) with adults modeling giving behaviors used to test sharing and the Inequity Game (IG, Experiment 2, N = 14 WS, 17 TD) used to test fairness.ResultsResults showed that the WS group behaved similarly to the TD group for baseline giving in the DG and in the IG, rejecting disadvantageous offers but accepting advantageous ones. However, after viewing an adult model giving behavior, the WS group gave more than their baseline, with many individuals giving more than half, while the TD group gave less. Combined these results suggest that social motivation is sufficient for sharing and, in particular, generous sharing, as well as the self-focused form of fairness. Further, individuals with WS appear capable of both learning to be more generous and preventing disadvantageous outcomes, a more complex profile than previously known.ConclusionsIn conclusion, the present study provides a snapshot into sharing and fairness-related behaviors in WS, contributing to our understanding of the intriguing social-behavioral phenotype associated with this developmental disorder.

Behavioral and Emotional Responding to Punishment in ADHD: Is Increased Emotionality Related to Altered Behavioral Responding?

Children with ADHD are theorized to experience increased negative emotional responses to punishment, compared to typically developing (TD) children, resulting in altered behavioral responding (Amsel, 1992). However, this has not been empirically tested. The current study evaluated the effects of punishment and reward on the behavioral and emotional responding of children with and without ADHD. Fifty-three children with ADHD (64.15% boys) and 46 TD children (47.83% boys), age 6-12, completed a task in which they chose between playing two simultaneously available games. Reward was arranged symmetrically across the games; responses on one game were punished four times as often as responses on the other game. Children's negative and positive emotional expressions were assessed during task completion with facial expression coding. Results indicated both groups showed a preference for playing the less punished game. Children with ADHD took longer to respond after punishment and reward compared to TD children. Negative emotional expressions increased with time on task for those with ADHD, the opposite pattern was seen in TD children. Children with ADHD showed more positive emotional expressions overall. The effect of ADHD on increased response times after reward was statistically fully mediated by increased positive facial expressions. Findings indicate children with ADHD do not show an altered response bias under punishment compared to TD children, but their cumulative negative emotional responding may indicate problems with building frustration tolerance as hypothesized by Amsel (1992). Results are theoretically important as they suggest increased emotional responding in ADHD is associated with slower responding.

Relation between stretch and activation of the medial gastrocnemius muscle during gait in children with cerebral palsy compared to typically developing children

Stretch hyperreflexia is often a target for treatment to improve gait in children with spastic cerebral palsy (CP). However, the presence of stretch hyperreflexia during gait remains debated. Therefore, we assessed the relation between gastrocnemius medialis muscle-tendon stretch and muscle activation during gait in children with CP compared to typically developing (TD) children. 3D gait analysis including electromyography (EMG) and dynamic ultrasound was carried out to assess, respectively gastrocnemius medialis activation and fascicle, belly, and tendon stretch during treadmill walking. Musculotendon-unit stretch was also estimated using OpenSim. Ratios of EMG/peak lengthening velocities and accelerations were compared between CP and TD. Velocity and acceleration peaks prior to EMG peaks were qualitatively assessed. EMG/velocity and EMG/acceleration ratios were up to 500% higher for CP (n = 14) than TD (n = 15) for most structures. Increased late swing muscle activation in CP was often preceded by fascicle and musculotendon-unit peak lengthening velocity, and early stance muscle activation by peaks in multiple structures. Increased muscle activation in CP is associated with muscle-tendon stretch during gait. Concluding, late swing muscle activation in CP appears velocity-dependent, whereas early stance activation can be velocity- and acceleration-dependent. These insights into stretch reflex mechanisms during gait can assist development of targeted interventions.

Executive Functioning Profiles in Neurodevelopmental Disorders: Parent-Child Outcomes.

Children with autism spectrum disorder (ASD) and/or attention deficit hyperactivity disorder (ADHD) exhibit more executive function (EF) deficits compared to typically developing (TD) peers. EF deficits are linked to various impairments in daily functioning and increased parental stress. The first aim of the present study is to investigate EFs in children with ASD and ADHD compared to their TD peers. The second aim is to explore profiles of executive functions in children with ASD and ADHD and, finally, to determine the differences of EF profiles in relation to parental stress and children's functional impairments. The sample comprised 30 TD children, 47 children with ASD, and 34 children with ADHD, aged 8 to 12 years. Parents completed questionnaires of parenting stress, and children's social and daily-life functioning. Parents and teachers reported information about children's EF. The results indicated significantly greater impairment of EFs in the clinical groups compared to the TD group. Moreover, three distinct clusters of functioning were identified based on the severity of reported EF difficulties. The significant findings showed that children with more severe EF profiles were associated with greater daily impairment and higher levels of perceived parental stress. Given the impact of EF deficits on the lives of children with ASD and ADHD and their families, it is crucial that studies like this enhance our understanding and inspire future interventions aimed at improving executive functions in children with ASD and ADHD. Such interventions could help reduce parental stress and improve daily functioning.

The Relationship between Story Comprehension, Story Grammar Production, and Executive Function in Preschool-Age Korean-English Bilingual Children with and without Vocabulary Delay

Objectives: This study investigated the relationship between story comprehension and story grammar abilities, as well as executive function in preschool Korean-English bilingual children with vocabulary delay (VD) compared to typically developing (TD) children and examined predictors of their narrative abilities. Methods: A total of 30 children (13 children with VD, 17 TD children) aged from 4-6 years participated in the study. Children performed non-word repetition (NWR) and word list recall for verbal working memory, matrix for non-verbal working memory, fruit stroop for inhibition, and Dimensional Change Card Sort (DCCS) for shifting. They also performed story comprehension and story grammar production tasks in both languages to assess their narrative abilities. For data analyses, one-way ANOVA, Pearson correlation, and stepwise multiple regression were conducted. Results: The VD group showed significantly lower performance in working memory, inhibition, shifting tasks. Moreover, VD group had significantly lower performance in story comprehension and story grammar production tasks in both languages. In the TD group, Korean story comprehension performance was correlated with English story comprehension, Korean story grammar production, English story grammar production performances. On the other hand, in the VD group, only Korean story comprehension showed a significant correlation with Korean story grammar production performance. Lastly, matrix significantly predicted English story comprehension abilities and word list recall significantly predicted Korean story grammar production abilities in the TD group. Conclusion: By examining the relationship between children’s ability to understand stories, produce story grammar and sub-factors of executive function, we can improve the narrative education and intervention for bilingual children’s literacy and academic achievement in the future.

Collagen architecture and biomechanics of gracilis and adductor longus muscles from children with cerebral palsy.

Cerebral palsy (CP) describes some upper motoneuron disorders due to non-progressive disturbances occurring in the developing brain that cause progressive changes to muscle. While longer sarcomeres increase muscle stiffness in patients with CP compared to typically developing (TD) patients, changes in extracellular matrix (ECM) architecture can increase stiffness. Our goal was to investigate how changes in muscle and ECM architecture impact muscle stiffness, gait and joint function in CP. Gracilis and adductor longus biopsies were collected from children with CP undergoing tendon lengthening surgery for hamstring and hip adduction contractures, respectively. Gracilis biopsies were collected from TD patients undergoing anterior cruciate ligament reconstruction surgery with hamstring autograft. Muscle mechanical testing, two-photon imaging and hydroxyproline assay were performed on biopsies. Corresponding data were compared to radiographic hip displacement in CP adductors (CPA), gait kinematics in CP hamstrings (CPH), and joint range of motion in CPA and CPH. We found at matched sarcomere lengths muscle stiffness and collagen architecture were similar between TD and CP hamstrings. However, CPH stiffness (R2=0.1973), collagen content (R2=0.5099) and cross-linking (R2=0.3233) were correlated to decreased knee range of motion. Additionally, we observed collagen fibres within the muscle ECM increase alignment during muscular stretching. These data demonstrate that while ECM architecture is similar between TD and CP hamstrings, collagen fibres biomechanics are sensitive to muscle strain and may be altered at longer in vivo sarcomere lengths in CP muscle. Future studies could evaluate the impact of ECM architecture on TD and CP muscle stiffness across in vivo operating ranges. KEY POINTS: At matched sarcomere lengths, gracilis muscle mechanics and collagen architecture are similar in TD patients and patients with CP. In both TD and CP muscles, collagen fibres dynamically increase their alignment during muscle stretching. Aspects of muscle mechanics and collagen architecture are predictive of in vivo knee joint motion and radiographic hip displacement in patients with CP. Longer sarcomere lengths in CP muscle in vivo may alter collagen architecture and biomechanics to drive deficits in joint mobility and gait function.

Alterations in resting-state gamma-activity is adults with autism spectrum disorder: A High-Density EEG study

Autism spectrum disorder (ASD) is a neurodevelopmental disorder with a wide range of symptoms that include deficits in social cognition and difficulties with social interactions. Neural oscillations in the EEG gamma band have been proposed as an important candidate neurobiological marker of higher order cognitive processes and social interactions. We investigated resting-state gamma-activity of patients with ASD (n=23) in order to delineate alterations as compared to typically developing (TD) subjects (n=24). EEG absolute power was examined in the gamma (30-100Hz) frequency band. We found significantly reduced spectral power across the entire gamma range in the ASD group. The decrease was most pronounced over the inferior-frontal and temporo-parietal junction areas. We also found a significant decrease in gamma-activity over the dorsolateral prefrontal cortex, especially in the left side. Since these brain areas have been associated with social functioning, the reduced gamma-activity in ASD may represent a cortical dysfunction that could underlie a diminished capacity to interpret socially important information, thereby interfering with social functioning. The alterations we found may lend support for an improved diagnosis. Furthermore, they can lead to focused therapies, by targeting the dysfunctional brain activity to improve social cognitive and interaction abilities that are compromised in ASD.

NARP-related alterations in the excitatory and inhibitory circuitry of socially isolated mice: developmental insights and implications for autism spectrum disorder.

Social isolation during critical periods of development is associated with alterations in behavior and neuronal circuitry. This study aimed to investigate the immediate and developmental effects of social isolation on firing properties, neuronal activity-regulated pentraxin (NARP) and parvalbumin (PV) expression in the prefrontal cortex (PFC), social behavior in juvenile socially isolated mice, and the biological relevance of NARP expression in autism spectrum disorder (ASD). Mice were subjected to social isolation during postnatal days 21-35 (P21-P35) and were compared with group-housed control mice. Firing properties in the PFC pyramidal neurons were altered in P35 socially isolated mice, which might be associated with alterations in NARP and PV expression. In adulthood, mice that underwent juvenile social isolation exhibited difficulty distinguishing between novel and familiar mice during a social memory task, while maintaining similar levels of social interaction as the control mice. Furthermore, a marked decrease in NARP expression in lymphoblastoid cell lines derived from adolescent humans with ASD as compared to typically developing (TD) humans was found. Our study highlights the role of electrophysiological properties, as well as NARP and PV expression in the PFC in mediating the developmental consequences of social isolation on behavior.

Cortical grey matter volume differences in children with developmental coordination disorder compared to typically developing children.

The cause of Developmental Coordination Disorder (DCD) is unknown, but neuroimaging evidence suggests that DCD may be related to altered brain development. Children with DCD show less structural and functional connectivity compared to typically developing (TD) children, but few studies have examined cortical volume in children with DCD. The purpose of this study was to investigate cortical grey matter volume using voxel-based morphometry (VBM) in children with DCD compared to TD children. This cross-sectional study was part of a larger randomized-controlled trial (ClinicalTrials.gov ID: NCT02597751) that involved various MRI scans of children with/without DCD. This paper focuses on the anatomical scans, performing VBM of cortical grey matter volume in 30 children with DCD and 12 TD children. Preprocessing and VBM data analysis were conducted using the Computational Anatomy Tool Box-12 and a study-specific brain template. Differences between DCD and TD groups were assessed using a one-way ANOVA, controlling for total intracranial volume. Regression analyses examined if motor and/or attentional difficulties predicted grey matter volume. We used threshold-free cluster enhancement (5,000 permutations) and set an alpha level of 0.05. Due to the small sample size, we did not correct for multiple comparisons. Compared to the TD group, children with DCD had significantly greater grey matter in the left superior frontal gyrus. Lower motor scores (meaning greater impairment) were related to greater grey matter volume in left superior frontal gyrus, frontal pole, and right middle frontal gyrus. Greater grey matter volume was also significantly correlated with higher scores on the Conners 3 ADHD Index in the left superior frontal gyrus, superior parietal lobe, and precuneus. These results indicate that greater grey matter volume in these regions is associated with poorer motor and attentional skills. Greater grey matter volume in the left superior frontal gyrus in children with DCD may be a result of delayed or absent healthy cortical thinning, potentially due to altered synaptic pruning as seen in other neurodevelopmental disorders. These findings provide further support for the hypothesis that DCD is related to altered brain development.

The self-reported driving and pedestrian behaviour of adults with developmental coordination disorder.

Developmental coordination disorder (DCD) affects movement coordination, but little is known about how the condition impacts the behaviours of car drivers and pedestrians. This study examined the self-reported driving and pedestrian behaviours of adults with Developmental Coordination Disorder (DCD). One hundred and twenty-eight participants (62 adults with DCD vs. 66 TD adults) responded to an online survey asking them about their perceptions of confidence and self-reported driving and pedestrian behaviours in the real-world. Results suggested that adults with DCD felt less confident and reported more lapses in attention (e.g., forgetting where their car was parked) and errors (e.g., failing to check their mirrors prior to a manoeuvre) when driving compared to typically developed (TD) adults. Adults with DCD also reported feeling less confident and reported less adherence to road traffic laws (e.g., not waiting for a green crossing signal before crossing the road) when walking as pedestrians. These results offer some much-needed insight into the behaviours of those with DCD outside of the laboratory environment and underline the need for research investigating the driving and pedestrian behaviours of individuals with DCD in 'real-world' contexts.

Playing for cognition: investigating the feasibility and user experience of a virtual reality serious game for cognitive assessment in children with congenital heart disease

BackgroundIn order to facilitate the development and implementation of innovative technology in clinical practice, it is important to understand the user experience of end-users. Virtual Reality (VR) offers the possibility to assess cognitive functioning in a dynamic environment that simulates real-world situations. The purpose of this cross-sectional study was to investigate the feasibility of a VR Serious Game for cognitive assessment in school-aged children with congenital heart disease (CHD). The sub-aims were two-fold: (1) to objectively evaluate the feasibility of the VR Serious Game in children with CHD in comparison to typically developing (TD) children and (2) to explore the user experience of both groups following their interaction with the VR Serious Game.ResultsA total of 101 children participated in this study; 98 children were included in the final analysis (CHD: n = 54; TD: n = 47). The VR Serious Game appeared feasible for both children with CHD and TD children, with 88% children completing the innovative VR assessment without encountering any issues. There were no discernible differences in completion rates between groups. Children with CHD reported significantly lower scores than TD children on three user experience scales: Engagement, Flow and Presence. Nonetheless, the scores for Engagement and Flow were still considered "moderate to good". Both groups reported minimal adverse physiological reactions.ConclusionsThe findings suggested that the VR Serious Game was feasible for children with CHD and that the user experience was positive. Future research should investigate the effectiveness of the VR Serious Game compared with a conventional or digital neuropsychological assessment, prioritising the development of novel outcome measures that can better estimate and explain the impact of cognitive impairment on daily functioning.

Gamma activity in Autism Spectrum Disorder: Enhanced response to visual input

IntroductionAutism spectrum disorder (ASD) is a childhood onset neurodevelopmental condition, that leads to permanent disability in a high proportion of cases. ASD is associated with a heterogeneous symptom presentation, which - besides social interaction and communication difficulties - encompasses altered sensory reactivity, including excessive hyper-sensitivity to stimuli, especially in the visual domain. Meta-analyses of fMRI studies revealed increased reactivity in visual task conditions in the temporal and occipital brain regions. Neural oscillations in the EEG gamma band are viewed as a candidate neurobiological marker for higher order sensory and perceptual processes, and social interactions.ObjectivesWe investigated changes in gamma activity in the EEG in the eyes open (EO) vs. eyes closed (EC) condition in order to identify the neurobiological underpinning of the enhanced sensitivity to visual input in ASD as compared to typically developing (TD) subjects.MethodsEEGs were obtained in EC and EO condition in ASD (N=23) and TD subjects (N=24) in an ongoing study. For EEG recording we used a high-density 128-channel BioSemi system, with 0.5 Hz frequency resolution. The spectral power in the gamma band (30-100Hz) was quantified by the power spectral density. To investigate whether changes in the gamma band were linked to changes in arousal instead of enhanced visual processing, we also examined alterations in the alpha band (8-13Hz) in the EO condition. Spectral power changes were determined for each EEG channel by computing the difference between the EC and EO conditions (EO-EC).ResultsSpectral power in the gamma band showed changes in the opposite direction in the two study groups: ASD subjects manifested significant (p<0.05) increase, while TD subjects had a decrease in the EO vs. EC condition in the temporal and occipital brain regions. By contrast, the changes in the alpha band were similar, with both groups exhibiting a spectral power decrease in the EO compared to the EC condition.ConclusionsIn ASD, an enhancement of gamma activity is present in the EO as compared to the EC condition in the posterior brain areas. These brain areas are involved in the processing of visual information, and gamma activity is considered as a measure of perceptual processes. Thus, the gamma alterations in the EO vs. EC condition may underlie the hyper-sensitivity symptoms to visual stimuli in ASD, and EEG can offer a simple to use tool to delineate the neurobiological foundation of the symptom presentation.Funding statement: Hungarian Brain Research program,#NAP2022-I-4/2022Disclosure of InterestNone Declared

Functional connectivity of the sensorimotor cerebellum in autism: associations with sensory over-responsivity.

The cerebellum has been consistently shown to be atypical in autism spectrum disorder (ASD). However, despite its known role in sensorimotor function, there is limited research on its association with sensory over-responsivity (SOR), a common and impairing feature of ASD. Thus, this study sought to examine functional connectivity of the sensorimotor cerebellum in ASD compared to typically developing (TD) youth and investigate whether cerebellar connectivity is associated with SOR. Resting-state functional connectivity of the sensorimotor cerebellum was examined in 54 ASD and 43 TD youth aged 8-18 years. Using a seed-based approach, connectivity of each sensorimotor cerebellar region (defined as lobules I-IV, V-VI and VIIIA&B) with the whole brain was examined in ASD compared to TD youth, and correlated with parent-reported SOR severity. Across all participants, the sensorimotor cerebellum was functionally connected with sensorimotor and visual regions, though the three seed regions showed distinct connectivity with limbic and higher-order sensory regions. ASD youth showed differences in connectivity including atypical connectivity within the cerebellum and increased connectivity with hippocampus and thalamus compared to TD youth. More severe SOR was associated with stronger connectivity with cortical regions involved in sensory and motor processes and weaker connectivity with cognitive and socio-emotional regions, particularly prefrontal cortex. These results suggest that atypical cerebellum function in ASD may play a role in sensory challenges in autism.

Grid-tuned ensemble models for 2D spectrogram-based autism classification

BackgroundAutism spectrum disorder (ASD) is a prevalent collection of developmental disorders that affects around one in every 36 children worldwide. Since autistic children exhibit aberrant electroencephalogram (EEG) signals in comparison to typically developing (TD) children, many authors have recently proposed several machine learning (ML) and deep learning (DL) models to classify ASD patients using EEG signals. However, these models lack extensive and large-scale feature extraction and apply multiple benchmark datasets. Furthermore, most of the proposed ML models need feature engineering to extract key features for classification. MethodThis study proposed a DL-based weighted ensemble model to avoid the need for feature engineering. The proposed model is based on finding the best suitable combination of weights using a grid search strategy, treating the highest weighted model as the most accurate, and giving more weightage. The strength of the suggested technique involves extracting features from EEG recordings by transforming raw EEG into multi-channel two-dimensional time–frequency maps (2D spectrograms) using the short-time Fourier transform (STFT). Furthermore, it applies two widely-researched public EEG datasets [i.e., the King Abdulaziz University (KAU) and the University of Sheffield (TUOS) databases] for performance comparison and better generalizability. Additionally, the performance of the proposed model has been compared with other well-known DL models, and our proposed straightforward, easily implemented models surpass these models in terms of accuracy and training time. ResultsThe suggested model yields an accuracy of 94.71% for ASD classification using the KAU dataset and 96.22% accuracy for utilizing the TUOS dataset. ConclusionsEnsembled models can efficiently enhance accuracy, stability, and reproducibility. The demonstrated finding solidifies the applicability of the weighted ensemble model to classify ASD patients utilizing EEG data. The suggested model might be used as a supplemental tool to assist neurologists in diagnosing ASD.

Individual variation in bilingual vocabulary in preschoolers with developmental language disorder

BackgroundIt is unclear how speech production, selective attention, and phonological working memory are related to first- (L1) and second-language (L2) vocabularies in bilingual preschoolers with Developmental Language Disorder (DLD). AimsTo study individual variation in vocabularies in DLD bilingual preschoolers by (1) comparing them to typically developing (TD) bilingual, and TD and DLD monolingual peers; (2) differentially predicting L2 vocabulary; and (3) identifying and characterizing bilinguals’ L1/L2 vocabulary profiles. MethodsWe measured the selective attention, working memory, and L1 Turkish/Polish (where applicable) and L1/L2 Dutch speech and vocabulary abilities of 31 DLD bilingual, 37 TD bilingual, and 61 DLD and 54 TD Dutch monolingual three-to-five year-olds. ResultsDLD bilinguals scored lower than TD bilinguals and TD/DLD monolinguals on all measures, except L2 vocabulary, where all bilinguals underperformed all monolinguals. Selective attention predicted Dutch vocabulary across groups. Three bilingual vocabulary profiles emerged: DLD bilinguals were less likely to be L1 dominant, TD/DLD bilinguals with better attention more often had a Balanced high L1/L2 profile, while those with poorer selective attention and L1 speech tended to be L2 dominant. ConclusionsThese findings highlight the roles of L1 speech and selective attention, rather than L2 speech and working memory, in understanding bilingual vocabulary variation among DLD preschoolers.

Cortico-basal ganglia white matter microstructure is linked to restricted repetitive behavior in autism spectrum disorder

BackgroundRestricted repetitive behavior (RRB) is one of two behavioral domains required for the diagnosis of autism spectrum disorder (ASD). Neuroimaging is widely used to study brain alterations associated with ASD and the domain of social and communication deficits, but there has been less work regarding brain alterations linked to RRB.MethodsWe utilized neuroimaging data from the National Institute of Mental Health Data Archive to assess basal ganglia and cerebellum structure in a cohort of children and adolescents with ASD compared to typically developing (TD) controls. We evaluated regional gray matter volumes from T1-weighted anatomical scans and assessed diffusion-weighted scans to quantify white matter microstructure with free-water imaging. We also investigated the interaction of biological sex and ASD diagnosis on these measures, and their correlation with clinical scales of RRB.ResultsIndividuals with ASD had significantly lower free-water corrected fractional anisotropy (FAT) and higher free-water (FW) in cortico-basal ganglia white matter tracts. These microstructural differences did not interact with biological sex. Moreover, both FAT and FW in basal ganglia white matter tracts significantly correlated with measures of RRB. In contrast, we found no significant difference in basal ganglia or cerebellar gray matter volumes.LimitationsThe basal ganglia and cerebellar regions in this study were selected due to their hypothesized relevance to RRB. Differences between ASD and TD individuals that may occur outside the basal ganglia and cerebellum, and their potential relationship to RRB, were not evaluated.ConclusionsThese new findings demonstrate that cortico-basal ganglia white matter microstructure is altered in ASD and linked to RRB. FW in cortico-basal ganglia and intra-basal ganglia white matter was more sensitive to group differences in ASD, whereas cortico-basal ganglia FAT was more closely linked to RRB. In contrast, basal ganglia and cerebellar volumes did not differ in ASD. There was no interaction between ASD diagnosis and sex-related differences in brain structure. Future diffusion imaging investigations in ASD may benefit from free-water estimation and correction in order to better understand how white matter is affected in ASD, and how such measures are linked to RRB.