Guess What? Comparing Ad-hoc and Scalar Implicatures in Children with Autism Spectrum Disorder

Children with autism spectrum disorders (ASD) often exhibit motor clumsiness (Developmental Coordination Disorder, DCD), i.e. they struggle with everyday tasks that require motor coordination like dressing, self-care, and participating in sport and leisure activities. Previous studies in these neurodevelopmental disorders have demonstrated functional abnormalities and alterations of white matter microstructural integrity in specific brain regions. These findings suggest that the global organization of brain networks is affected in DCD and ASD and support the hypothesis of a 'dys-connectivity syndrome' from a network perspective. No studies have compared the structural covariance networks between ASD and DCD in order to look for the signature of DCD independent of comorbid autism. Here, we aimed to address the question of whether abnormal connectivity in DCD overlaps that seen in autism or comorbid DCD-autism. Using graph theoretical analysis, we investigated differences in global and regional topological properties of structural brain networks in 53 children: 8 ASD children with DCD (DCD+ASD), 15 ASD children without DCD (ASD), 11 with DCD only, and 19 typically developing (TD) children. We constructed separate structural correlation networks based on cortical thickness derived from Freesurfer. The children were assessed on the Movement-ABC and the Beery Test of Visual Motor Integration. Behavioral results demonstrated that the DCD group and DCD+ASD group scored on average poorer than the TD and ASD groups on various motor measures. Furthermore, although the brain networks of all groups exhibited small-world properties, the topological architecture of the networks was significantly altered in children with ASD compared with DCD and TD. ASD children showed increased normalized path length and higher values of clustering coefficient. Also, paralimbic regions exhibited nodal clustering coefficient alterations in singular disorders. These changes were disorder-specific, and included alterations in clustering coefficient in the isthmus of the right cingulate gyrus and the pars orbitalis of the right inferior frontal gyrus in ASD children, and DCD-related increases in the lateral orbitofrontal cortex. Children meeting criteria for both DCD and ASD exhibited topological changes that were more widespread from those seen in children with only DCD, i.e. children with DCD+ASD showed alterations of clustering coefficient in (para)limbic regions, primary areas, and association areas. The DCD+ASD group showed changes in clustering coefficient in the left association cortex relative to the ASD group. Finally, the DCD+ASD group shared ASD-specific abnormalities in the pars orbitalis of right inferior frontal gyrus, which was hypothesized to reflect atypical emotional-cognitive processing. Our results provide evidence that DCD and ASD are neurodevelopmental disorders with a low degree of overlap in abnormalities in connectivity. The co-occurrence of DCD+ASD was also associated with a distinct topological pattern, highlighting the unique neural signature of comorbid neurodevelopmental disorders.

The objective of this study is to investigate whether parentally-reported gastro-intestinal (GI) symptoms are increased in a population-derived sample of children with autism spectrum disorders (ASD) compared to controls. Participants included 132 children with ASD and 81 with special educational needs (SEN) but no ASD, aged 10-14years plus 82 typically developing (TD) children. Data were collected on GI symptoms, diet, cognitive abilities, and developmental histories. Nearly half (weighted rate 46.5%) of children with ASD had at least one individual lifetime GI symptom compared with 21.8% of TD children and 29.2% of those with SEN. Children with ASD had more past and current GI symptoms than TD or SEN groups although fewer current symptoms were reported in all groups compared with the past. The ASD group had significantly increased past vomiting and diarrhoea compared with the TD group and more abdominal pain than the SEN group. The ASD group had more current constipation (when defined as bowel movement less than three times per week) and soiling than either the TD or SEN groups. No association was found between GI symptoms and intellectual ability, ASD severity, ASD regression or limited or faddy diet. Parents report more GI symptoms in children with ASD than children with either SEN or TD children but the frequency of reported symptoms is greater in the past than currently in all groups.

Individuals with autism spectrum disorders (ASD) often exhibit difficulties in sensory processing, including visual hypersensitivity such as photophobia. This study investigates the neural mechanisms underlying photophobia in participants with ASD by analyzing pupillary responses. To achieve this, we examined the amplitude and velocity gradient (latency) of these responses. Pupillary responses were recorded using an eye-tracking system in participants with ASD (n = 17) and typically developing (TD) (n = 23). Stimuli alternated between bright (89.03 cd/m2) and dark (0.07 cd/m2) conditions following a dim state (2.75 cd/m2) with intervals of five seconds in Experiment 1 and 30 seconds in Experiment 2. The sensory profile test (AASP-J) showed that hypersensitivity was significantly defined in the ASD group than in the TD group. The pupillary response in the ASD group often featured missing values due to blinking during rapid alternation between bright and dark conditions, resulting in a decrease in the total number of participants. Specifically, only eight of the 17 participants in the ASD group and 20 of the 23 participants in the TD group remained for analysis in Experiment 1, and in Experiment 2, 15 of the 17 participants in the ASD group and 20 of the 23 participants in the TD group remained for analysis. In the dim state, pupillary diameter was large in the ASD and TD group in both experiments, while the pupil diameter decreased in the TD group in Experiment 2. In both experiments, maximum amplitude and its latency showed no significant differences between the two groups. However, the velocity gradient for the early mydriatic process in the dark condition was significantly faster in the ASD group. ASD individuals with hypersensitivity tend to have large pupil diameters under the dim state, as well as rapid dilation in the dark condition. These results may suggest a problem in the sympathetic nervous system, which controls pupil constriction.

Neurological, structural, and behavioral abnormalities are widely reported in individuals with autism spectrum disorder (ASD); yet there are no objective markers to date. We postulated that by using dominant and nondominant ear data, underlying differences in auditory evoked potentials (AEPs) between ASD and control groups can be recognized. The primary purpose was to identify if significant differences exist in AEPs recorded from dominant and nondominant ear stimulation in (1) children with ASD and their matched controls, (2) adults with ASD and their matched controls, and (3) a combined child and adult ASD group and control group. The secondary purpose was to explore the association between the significant findings of this study with those obtained in our previous study that evaluated the effects of auditory training on AEPs in individuals with ASD. Factorial analysis of variance with interaction was performed. Forty subjects with normal hearing between the ages of 9 and 25 years were included. Eleven children and 9 adults with ASD were age- and gender-matched with neurotypical peers. Auditory brainstem responses (ABRs) and auditory late responses (ALRs) were recorded. Adult and child ASD subjects were compared with non-ASD adult and child control subjects, respectively. The combined child and adult ASD group was compared with the combined child and adult control group. No significant differences in ABR latency or amplitude were observed between ASD and control groups. ALR N1 amplitude in the dominant ear was significantly smaller for the ASD adult group compared with their control group. Combined child and adult data showed significantly smaller amplitude for ALR N1 and longer ALR P2 latency in the dominant ear for the ASD group compared with the control group. In our earlier study, the top predictor of behavioral improvement following auditory training was ALR N1 amplitude in the dominant ear. Correspondingly, the ALR N1 amplitude in the dominant ear yielded group differences in the current study. ALR peak N1 amplitude is proposed as the most feasible AEP marker in the evaluation of ASD.

Objective To explore the developmental characteristics of white matter volume in autism spectrum disorder (ASD) children longitudinal. Methods From May 2011 to September 2014, 37 ASD children (ASD group) and 27 developmental delays (DD) children (control group) were treated at the Child Mental Health Research Center, Nanjing Brian Hospital Affiliated of Nanjing Medical University, and the children whose age, gender and developmental quotient matched with the ASD children were scanned by structure magnetic resonance imaging (sMRI) at the age of 2-3 years old and 4-5 years old respectively.Region of interest(ROI) technology was adopted to investigate the change of the cerebrum white and the sub-lobes structure white matter volume with time.Then the correlation between clinical symptoms and brain white matter volume changes was analyzed. Results Among the 2-3 years old, compared with the control group, the white matter volume of the total brain[(383 521.84±6 427.57) mm3vs. (364 014.06±6 856.97) mm3], the left cerebral hemisphere [(191 609.35±3 206.60) mm3vs. (181 695.89±3 389.54) mm3], temporal lobe [(41 860.49±816.38) mm3vs. (39 444.18±834.85) mm3] and the right temporal lobe [(21 312.79±414.07) mm3vs. (20 084.22±412.13) mm3] were significantly larger in the ASD group, and the differences were statistically significant (all P 0.05). Among the 4-5 years old, compared with the control group, the white matter volumes of the total brain[(417 651.42±6 443.86) mm3vs. (394 317.27±6 404.86) mm3], left cerebral hemisphere [(208 714.16±3 214.61) mm3vs. (197 192.82±3 262.02) mm3], right cerebral hemisphere [(208 937.26±3 242.09) mm3vs. (7 124.45±3 193.13) mm3], frontal lobe [(107 107.46±1 681.99) mm3vs. (100 326.19±1 883.24) mm3], left frontal lobe [(54 569.63±846.85) mm3vs. (51 177.25±979.09) mm3], right frontal lobe [(52 537.83±841.99) mm3vs. (49 148.94±928.31) mm3], temporal lobe [(45 189.75±833.29) mm3vs.(42 487.73±786.27) mm3], left temporal lobe [(22 204.21±411.77) mm3vs. (20 922.90±418.46) mm3], and right temporal lobe [(22 985.54±426.93) mm3vs. (21 564.83±378.78) mm3] were significantly larger in the ASD group, and the differences were statistically significant (all P 0.05). For longitudinal analysis, there was a significant difference in the white matter volume between the whole brain, left cerebral hemisphere, right cerebral hemisphere, frontal lobe, left frontal lobe, right frontal lobe, temporal lobe, left temporal lobe, right temporal lobe and the differences were statistically significant(F=5.521, 5.533, 5.459, 5.830, 5.800, 5.723, 4.857, 4.418, 5.159, all P<0.05). There was a positive correlation between the changes of the volume of whole brain, the white matter volume in the whole brain, bilateral cerebral hemisphere, frontal lobe, parietal lobe, right parietal lobe and Childhood Autism Rating Scale(r=0.367, 0.343, 0.321, 0.349, 0.296, 0.308, 0.351, all P<0.05). Conclusions Among the 2-3 years old, the white matter volume of the brain regions have been increased significantly in ASD.Among the 4-5 years old, the increase of the white matter volume of the brain regions implicated more widely which mainly concentrated in the frontal and temporal lobe in ASD.The severity of the clinical symptoms of ASD may be associated with the white matter volume of the total brain, bilateral cerebral hemisphere, frontal lobe, parietal lobe and right parietal lobe. Key words: Autism spectrum disorder; White matter; Volume; Magnetic resonance imaging; Longitudinal study

Infants' representation of events: Studies in imitation, cross-modal perception, and categorization

Robots are becoming a part of humans' social life as assistants, companionbots, therapists, and entertainers. One promising application of the socially assistive robots is in autism therapy, where robots are employed to enhance verbal and nonverbal skills (e.g. eye-gaze attention, facial expression mimicry) of individuals with Autism Spectrum Disorder (ASD). One important question is How the gaze responses of individuals with ASD differ from that of Typically Developing (TD) peers when interacting with a robot? We present the results of our recent studies for modeling and analyzing the gaze pattern of children with ASD when they interact with a robot called NAO. This paper reports the differences of gaze responses of TD and ASD group in two conversational contexts: Speaking versus Listening. We used Variable-order Markov Model (VMM) to discover the temporal gaze directional patterns of ASD and TD groups. The results reveal that the gaze responses of the TD individuals in speaking and listening contexts, can be best modeled by VMM with order zero and three, respectively. As we expected, the result show that the temporal gaze patterns of typically developed children are varying when the role in the conversational context is changed. However for the ASD individuals for both conversational contexts the VMM with order one could best fit the data. Overall, the results conclude that VMM is a powerful technique to model different gaze responses of TD and ASD individuals in speaking and listening contexts.

Iron deficiency in subcortical structures has been reported in previous studies using manually drawn regions of interest (ROIs). However, no whole-brain iron content studies in individuals with autism spectrum disorder (ASD) have been published. This study aimed to explore whole-brain iron content in ASD children using quantitative susceptibility mapping (QSM) and to examine relationships between clinical features of ASD and regional susceptibility values. A total of 30 ASD children and 28 typically developing (TD) individuals who were matched for age and sex were prospectively recruited. Brain MRI scans were performed on each participant. Each brain region's susceptibility value was compared between groups, and correlations with clinical manifestations were examined. The ASD patients showed significantly higher susceptibility values than TD children in the bilateral middle temporal gyrus, left inferior temporal gyrus, left inferior parietal gyrus, right lateral occipital gyrus, right insula, and bilateral rostral anterior cingulate gyrus. Conversely, significantly lower susceptibility was observed in the right cerebral white matter of ASD children. According to correlation analysis, susceptibility values in the left middle temporal gyrus, left inferior parietal gyrus, and right lateral occipital gyrus were negatively correlated with the Gesell Developmental Schedules (GDS) gross motor scores in the ASD group. ASD children had aberrant susceptibility values in cortical areas, and these abnormalities might be associated with their clinical features, which may provide new insights into understanding the pathophysiology of ASD.

Background: Narrative ability is a critical component of social communication essential for participating in everyday activities. Children with autism spectrum disorder (ASD) demonstrate problems in the narrative discourse, but little is known about the features of their fictional stories. Objectives: This study compared fictional narratives between ASD children and they’re typically developing (TD) peers. Methods: Fictional stories produced by 6- to-7-year-old males with high functioning autism (n = 14) were compared with language, sex, and age-matched TD children (n = 15). The stories were analyzed using the monitoring indicators of scholarly language. The macrostructure and microstructure elements, narrative complexity index, story knowledge index, and perspective-taking index were compared between the two groups by one-way analysis of variance (ANOVA) at the significance level of 0.05. Results: The scores of macrostructure and microstructure elements were lower in children with ASD. The ANOVA showed significant differences between ASD and TD children in three indices (P &lt; 0.05). Moreover, the Pearson correlation coefficients between the total macrostructure and microstructure scores were close to one in both ASD (r = 0.89) and TD children (r = 0.93). Conclusions: Despite obtaining scores in the average range in a standard language test, Farsi-speaking children with ASD experience limitations in fictional narratives.

Teaching and Learning Guide for: Pragmatics: From Theory to Experiment and Back Again

Background: Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder. Folate has been demonstrated to be associated with ASD. However, current studies on the correlation between folate and symptoms of children with ASD have inconsistent conclusions, use mainly small samples, and lack age-stratified analysis. This study aimed to explore the association between serum folate and symptoms of autistic children at different age groups from a multi-center perspective.Methods: We enrolled 1,300 children with ASD and 1,246 typically developing (TD) children under 7 years old from 13 cities in China. The Autism Behavior Checklist (ABC), Social Responsiveness Scale (SRS), and Childhood autism rating scale (CARS) were used to evaluate the symptoms of children with ASD. China neuropsychological and Behavior Scale-Revision 2016 (CNBS-R2016) scale was used to evaluate the neurodevelopment of children with ASD. Serum folate was measured by chemiluminescence assay in the two groups.Results: The serum folate levels of children with ASD were lower than that of TD children. In terms of core symptoms of ASD, we found that the serum folate levels were not associated with ABC, SRS, and CARS scores in ASD children of all ages but negatively associated with communication warning behavior scores of CNBS-R2016 in ASD children aged three and under. Concerning development quotients, it was at the age of three and under that serum folate levels were positively associated with gross motor, fine motor, language, and general quotient of ASD children. These ASD children aged three and under were further divided into two groups according to the median of serum folate (14.33 ng/mL); we found that compared to ASD children with folate ≤ 14.33 ng/mL, those with folate >14.33 ng/mL had lower communication warning behavior score and higher gross motor, fine motor, adaptive behavior, language, person-social, and general development quotients.Conclusion: We found that serum folate status was primarily associated with the neurodevelopment of children with ASD aged three and under. Furthermore, relatively higher serum folate levels may be more beneficial for children with ASD. Our results suggest that folate level should be paid more attention in ASD children, especially in early life, to better promote the intervention of ASD children.

Autism Spectrum Disorder (ASD) is a developmental condition characterized by difficulties in social interaction, communication, and sensory processing. The ability to orient towards sounds is a key component of social interactions, yet auditory spatial attention remains relatively understudied in ASD, despite prior research indicating differences in this domain. Here, we investigate the neural signatures associated with passive auditory spatial attention in children with ASD (n = 21, ages 6-17) relative to age- and IQ-matched Typically Developing (TD) children (n = 31), using source-localized magnetoencephalography (MEG). Participants listened passively, while watching a silenced movie, to non-social auditory stimuli designed to either remain lateralized to one hemifield (stay trials) or to change in location from one side to the contralateral hemifield (jump trials). Linear mixed effects modeling showed lower cortical activation in the auditory cortex in the ASD group in response to jump trials, relative to the TD group. Additionally, functional connectivity analyses showed higher alpha-band functional connectivity in the ASD group between left auditory cortex seeds and right prefrontal and left parietal regions known to be recruited during auditory spatial attention. Right prefrontal alpha-band connectivity estimates were associated with behaviorally assessed auditory processing scores, whereas left parietal connectivity estimates were associated with ASD symptomatology. Our results align with the hypothesis that auditory spatial attention generally, and specifically orientation to sounds even when experienced passively, differs in ASD versus TD children.

Clinical reports suggest that children with autism spectrum disorder (ASD) struggle with time perception, but few studies have investigated this. This is the first study to examine these children’s understanding of before and after. These temporal conjunctions have been argued to require additional cognitive effort when conjoining two events in a clause order that is incongruent with their order in time. Given the suggested time perception impairment and well-established cognitive deficits of children with ASD, we expected them to have difficulties interpreting temporal conjunctions, especially in an incongruent order. To investigate this, the interpretation of before and after in congruent and incongruent orders was examined in 48 children with ASD and 43 typically developing (TD) children (age 6–12). Additional tasks were administered to measure Theory of Mind (ToM), working memory (WM), cognitive inhibition, cognitive flexibility, IQ, and verbal ability. We found that children with ASD were less accurate in their interpretation of temporal conjunctions than their TD peers. Contrary to our expectations, they did not have particular difficulties in an incongruent order. Furthermore, older children showed better overall performance than younger children. The difference between children with ASD and TD children was explained by WM, ToM, IQ, and verbal ability, but not by cognitive inhibition and flexibility. These cognitive functions are more likely to be impaired in children with ASD than in TD children, which could account for their poorer performance. Thus, the cognitive factors found to affect the interpretation of temporal language in children with ASD are likely to apply in typical development as well. Sufficient WM capacity and verbal ability may help children to process complex sentences conjoined by a temporal conjunction. Additionally, ToM understanding was found to be related to children’s interpretation of temporal conjunctions in an incongruent order, indicating that perspective taking is required when events are presented out of order. We conclude from this that perspective-taking abilities are needed for the interpretation of temporal conjunctions, either to shift one’s own perspective as a hearer to another point in time, or to shift to the perspective of the speaker to consider the speaker’s linguistic choices.

The present study examined the recognition of numerical stimuli briefly presented in the peripheral and the central (foveal) visual fields of children with autism. The participants were 5 children with high-functioning Autism Spectrum Disorder (ASD) and 10 typically developing (TD) children of similar chronological age. The stimuli were number strings presented on a personal computer screen for 160 msec in the position of the fixation point (foveal condition) or in the peripheral visual field (retinal eccentricity of 16 degrees) in one of the eight radial positions selected randomly (peripheral condition). The participants' task was to report the number of stimuli. The results showed that there were no significant differences in the mean response times between the TD and ASD groups. However, the mean percentage of correct answers in the ASD group was significantly higher than in the TD group for the peripheral condition. These results suggest that the effective visual field of the ASD group is expanded compared with the TD group. We discussed the relationships between perceptual characteristics and cognitive processes particular to ASD children.

To compare parent reported sleep behaviors of children with Autism Spectrum Disorders (ASD) and normal healthy controls and to examine the association of sleep disturbances with daytime behavioral difficulties in children with ASD. Sixty ASD children (85% boys) (Mean age=6.1 y, SD=2.4) were recruited from the Psychology unit of the Department of Pediatrics of a tertiary care hospital. An age and socio-economic status matched group of typically developing (TD) children (N=60) were also recruited. The Children's Sleep Habits Questionnaire (CSHQ) was used to measure sleep problems. The Childhood Psychopathology Measurement Schedule was used to measure day time behavioral difficulties. Sleep problems were nearly two times more prevalent among children with ASD (88.3%) as compared to the TD group (46.7%) (χ2=23.74, P=0.0001). The total CSHQ and 6 out of the 8 subscales scores of the ASD group were also significantly higher than the TD group. Overall, children with ASD displayed significant more bedtime resistance than controls (t= 3.95, P=0.001). The sleep duration subscale showed that children with ASD, relative to the TD group, slept too little (χ2=23.08, P=0.0001), did not sleep the right amount of time (χ2= 11.86, P=0.003), and displayed significant variation in the duration of time slept (χ2=11.96, P=0.003). In addition, parent reported sleep dysfunction had a significant relationship with daytime reported behavior difficulties (r=0.53, P=0.01) in children with ASD. Stepwise multiple regression analysis revealed that 30% of the variance in number of daytime behavioral problems was explained by only two variables: total CSHQ scores and duration of night awake time (F=11.18, P=0.001). Children with ASD are at a high risk for sleep problems and this is associated with daytime behavior disturbances. Pediatricians should routinely screen ASD children for sleep problems and initiate timely and appropriate interventions.