Dysfunction of sensory oscillations in Autism Spectrum Disorder

Autism Spectrum Disorder (ASD) is a highly prevalent developmental disability characterized by deficits in social communication and interaction, restricted interests, and repetitive behaviors. Recently, anomalous sensory and perceptual function has gained an increased level of recognition as an important feature of ASD. A specific impairment in the ability to integrate information across brain networks has been proposed to contribute to these disruptions. A crucial mechanism for these integrative processes is the rhythmic synchronization of neuronal excitability across neural populations; collectively known as oscillations. In ASD there is believed to be a deficit in the ability to efficiently couple functional neural networks using these oscillations. This review discusses evidence for disruptions in oscillatory synchronization in ASD, and how disturbance of this neural mechanism contributes to alterations in sensory and perceptual function. The review also frames oscillatory data from the perspective of prevailing neurobiologically-inspired theories of ASD.     

Interoception in Autism Spectrum Disorder: A review

PurposeThis review article summarizes original scientific research published to date on interoception in individuals with Autism Spectrum Disorder (ASD). Sensory processing has been shown to be atypical in ASD, yet physiological processing and subjective experience of internal sensation processing, namely interoception, has not been reported sufficiently in research or clinical settings.BackgroundThere is a small but growing body of scientific research on interoception in ASD, which is relevant to understanding the behavioral and cognitive characteristics inherent in this condition, and may provide a foundation for clinical interventions such as biofeedback, pain management, and brain stimulation techniques.MethodsA literature review of original research was performed using major scientific databases.ResultsInteroception, which occurs due to multisensory connections and integration of internal afferents in cortical and subcortical areas, is atypical in ASD, but the degree and directionality of this abnormality is not yet clear due to the heterogeneity of the condition. Between-group interoceptive differences in individuals with and without ASD have been repeatedly demonstrated, with a slight tendency towards hyporeactivity in interoceptive awareness in individuals with ASD.SignificanceMultidimensional research combining neuroimaging with psychophysiological and self-report measures guided by a clear theoretical model is necessary to understand how interoceptive differences link to the behavioral and cognitive characteristics of ASD. Sensory processing models and autism theory should also be updated to incorporate these recent findings.     

A systematic review of the diagnostic stability of Autism Spectrum Disorder

There is debate in the current literature regarding the permanence of an Autism Spectrum Disorder (ASD) diagnosis. We undertook a systematic review of the diagnostic stability of ASD to summarise current evidence. A comprehensive search strategy was used to identify studies. Participants were children with ASD. Risk of bias was assessed by examining the sample selected, recruitment method, completeness of follow up, timing of diagnosis and blinding.Twenty three studies assessed diagnostic stability with a total of 1466 participants. Fifty three to100% of children still had a diagnosis of Autistic Disorder (AD) and 14-100% of children still had a diagnosis of another form of ASD at follow up. There is some evidence that Autistic Disorder is a reasonably stable diagnosis; however a significant minority of children will no longer meet diagnostic criteria after a period of follow up, particularly those diagnosed in the preschool years with cognitive impairment. Other Autism Spectrum Disorders have very variable stability between studies and clinicians when using this diagnosis need inform parents of its instability. This study supports the stricter diagnostic criteria in DSM-V. There is a need for long term, large population cohort studies measuring diagnostic stability.     

Emotion recognition from body movement and gesture in children with Autism Spectrum Disorder is improved by situational cues

BackgroundResearch shows people with Autism Spectrum Disorder (ASD) have poorer emotion recognition (ER) compared to their typically developing (TD) peers. However, it is not known whether this is the case when stimuli are limited to gesture and posture, and lack facial expressions.MethodFifty-four children with (n = 27) and without (n = 27) ASD, matched on age and gender, completed an ER task, that used dynamic stimuli. Processing style bias, Autistic-like-traits and empathy were also measured. With ER as the outcome variable, a multilevel logistic model was created.ResultsChildren with ASD were found to be significantly less accurate in identifying emotions, compared to the control group. Presence of situational cues aided both groups. Autistic-like-traits and empathy were found to correlate too highly with the diagnosed condition to use in the multilevel model. Processing style did not significantly impact ER ability.ConclusionsThis study supports previous research which finds ER ability in people with ASD to be poorer than that of TD peers and that situational cues can aid ER ability. Importantly, the latter is true for people with ASD. The implication of these findings are programmes that aim to improve ER should consider using cues. Limitations of the study are discussed.     

Education programmes for young children with Autism Spectrum Disorder: An Evaluation Framework

Autism researchers have identified a common set of practices that form the basis of quality programming in ASD yet little is known regarding the implementation of these practices in community settings. The purpose of this paper was to outline an Evaluation Framework for use in evaluating ASD programmes of education that will provide valuable information as to the sensitivity of programmes to best practice, establish how programmes are operating and the programme effect on students and their families. The move towards more rigorous evaluation will provide quality information as to the degree of adoption of research led practices in the community setting which heretofore has been largely unavailable.     

Behavioral comparisons in Autism Spectrum Disorder and Developmental Coordination Disorder: A systematic literature review

BackgroundAutism Spectrum Disorder (ASD) and Developmental Coordination Disorder (DCD) are developmental disorders that, since the DSM-5, can be diagnosed as co-occurring conditions. While some recent studies suggest that ASD and DCD have similar traits, others show clear behavioral distinctions between the two conditions. By gathering all studies that included (1) an ASD group and a DCD group, (2) an ASD + DCD group and a DCD group, or (3) ASD, ASD + DCD, and DCD groups, we aimed to identify similarities and differences in behaviors between the two disorders.MethodWe used a systematic search of PubMed (1946 –), Scopus (1970 –), PsycINFO (via EBSCO, 1600 –), CINAHL (via EBSCO, 1937 –), SportDiscus (via EBSCO, 1985 –), and WorldCat (via FirstSearch) in addition to reference list and author name searching PubMed, Scopus, PsycINFO, CINAHL, SportDiscus, and WorldCat to identify original studies that met the following criteria: (1) an ASD group and a DCD group, (2) an ASD + DCD group and a DCD group, or (3) ASD, ASD + DCD, and DCD groups.ResultsFrom the 1598 articles screened, 11 were included in the qualitative analysis. The articles included reported more differences than similarities in individuals with ASD and DCD, with clear distinctions for working memory ability, gestural performance, grip selection, and cortical thickness. Only two studies reported similarities in face processing abilities and perceived competence, and the interventional studies showed group similarities in behavior improvement, such as intelligence and attention.ConclusionsBased on the articles reviewed, we conclude that while DCD and ASD share some behavioral symptoms, the symptom profiles of each disorder are unique and separable. We recommend that the evaluation of potential DCD in individuals with ASD be performed systematically and thoroughly, so as to distinguish this co-occurring condition from sensorimotor symptoms associated with ASD.     

Attention and basic literacy and numeracy in children with Autism Spectrum Disorder: A one-year follow-up study

Little is known about the link between Executive Functioning (EF) and academic performance in children with Autism Spectrum Disorder (ASD) and how such links develop over time. This study examined word reading, basic mathematics, attention switching, sustained attention and their development. Two age, gender and perceptual IQ matched groups of cognitively able 7–12 year olds (ASD N = 40; typical developing [TYP] N = 40) were assessed at baseline and one year later, completing Word Reading and Numerical Operations tests and computerized tasks tapping attention switching and sustained attention. Children with ASD had similar word reading and numerical operations performance and similar development of these skills relative to TYP children. A delay in attention switching but similar development was found in children with ASD relative to TYP children. The EF tasks were correlated with reading and mathematics in ASD children only, however, in regression analyses these factors were not significant predictors of Time 2 reading and mathematics after accounting for Time 1 reading and mathematics scores. These findings indicate similar word reading and mathematics development but atypical attention profiles in cognitively able children with ASD. Implications for educators are discussed.     

Factors influencing waiting times for diagnosis of Autism Spectrum Disorder in children and adults

AimsTo identify the main factors predicting delays in diagnosis for Autism Spectrum Disorder (ASD) at three stages in the diagnostic process: wait for first appointment; assessment duration, and total wait for diagnosis.MethodData were gathered from 150 case notes (80 child and 70 adult cases) from 16 diagnosing services across Scotland.ResultsHaving more information pre-assessment was associated with a reduced duration of the diagnostic process for children. This relationship was partially mediated by a reduction in the number of contacts required for diagnosis. In adults, having more factors associated with ASD (increased risk) reduced the wait time from referral to first appointment, but increased the overall duration of the diagnostic process. The latter relationship was partially mediated by an increase in the number of contacts required for diagnosis.ConclusionWithin children's services, increasing the amount of relevant information available pre-assessment is likely to reduce total duration of the assessment process by reducing number of contacts required. Having a high risk of ASD as an adult appears to result in being seen more quickly following referral, but also to increase the number of contacts needed and assessment duration. As a result, it increases and total duration overall.     

Adaptation and validation of the Parental Behaviour Scale for Autism Spectrum Disorder in Chinese parents

BackgroundThe present study aimed to adapt and examine the psychometric properties of the Parental Behaviour Scale - ASD (PBS-A) in Chinese parents of young children with ASD.MethodsThe translated version of the PBS-A was administered to 416 parents of young children with ASD (sample 1) to examine the construct validity and internal consistencies. One hundred and five of them (sample 2) were followed-up a month later to examine the test-retest reliability. The Alabama Parenting Questionnaire (APQ), the Strength and Difficulties Questionnaire (SDQ) and the Autism Parenting Stress Inventory (APSI) were administered along with the Chinese version of the PBS-A (C-PBS-A) in Sample 3 (n = 110) to examine the criterion validity of the scale.ResultsThe original structure was not replicated, and a new seven-factor structure containing 41 items was determined using exploratory factor analysis. There were four dimensions measuring shared parenting behaviors with typically developing children and three dimensions measuring ASD-specific parenting behaviors. The internal consistencies and test-retest reliabilities of the C-PBS-A were acceptable. The positive correlations among subscales of the C-PBS-A and similar dimensions in the APQ supported good convergent validity. In support of predictive validity, supportive dimensions in the C-PBS-A were negatively correlated with children’s behavioral problems and parenting stress, while negative control dimensions were positively correlated with these two variables.ConclusionThe Chinese version of the Parental Behaviour Scale (ASD) has good validity and reliability. It can be used to measure the parenting behaviors among Chinese parents of young children with ASD in future research.     

The perspectives of students with Autism Spectrum Disorder on the transition from primary to secondary school: A systematic literature review

BackgroundThe transition from primary to secondary school is a period of intense sociocultural and environmental change, which can present specific challenges for children with Autism Spectrum Disorder (ASD). Children’s perspectives are often lacking in research on ASD, and this is also the case for research on children with ASD at the primary to secondary school transition.MethodThis systematic literature review serves an important purpose by comprehensively identifying and synthesising the empirical research on the first-hand accounts of children with ASD in relation to their transition from primary to secondary school.ResultsAcross the results of nine studies that met inclusion criteria, four core themes emerged: relationships, feelings and expectations regarding transition, facilitators and barriers of a successful transition, and heterogeneity of needs relating to ASD.ConclusionThe results emphasise the importance of reducing the concerns of children with ASD through transition planning as well as the adoption of a less negative narrative around the primary-secondary transition. Similar to their typically developing peers, children with ASD can have a positive experience of the primary-secondary transition.     

Brief Report: Atypical Social Cognition and Social Behaviours in Autism Spectrum Disorder: A Different Way of Processing Rather than an Impairment

A central question to autism research is whether autism is largely the result of an impairment in social cognition and/or motivation or the result of a more general processing difference. This review discusses problems with the “social deficit” model of autism spectrum disorder (ASD). It is suggested that superior attention to low-level perceptual information potentially coupled with decreased attention to global information may provide a more comprehensive explanation for atypical social behaviours in ASD. This processing style may reflect increased activation of occipital-temporal regions and reduced functional (and possibly anatomical) connectivity. It is concluded that atypical social behaviours in ASD are more likely to be a consequence reflective of a general processing difference than impairment in social cognition and/or motivation.     

Synergic effect of GSTP1 and blood manganese concentrations in Autism Spectrum Disorder

We used data from 100 age- and sex-matched case-control pairs (age 2–8 years) from Jamaica to investigate whether there is an interaction between glutathione-S-transferase (GST) genes and blood manganese concentrations (BMC) in relation to Autism Spectrum Disorder (ASD). Our findings, indicate that among children who had the Ile/Ile genotype for GST pi 1 (GSTP1), those with BMC ≥ 12 μg/L had about 4 times higher odds of ASD than those with BMC < 12 μg/L, (P = 0.03) under a co-dominant genetic model. After adjusting for potential confounders, among the subgroup of children with genotype Ile/Ile, those with BMC ≥ 12 μg/L had about six times higher odds of ASD than those with BMC < 12 μg/L, (P = 0.04). The results were similar when a recessive genetic model was used. These findings suggest a possible synergic effect of BMC and GSTP1 in ASD. Since our analysis included a variety of genetic models and was not adjusted for multiple testing, replication in other populations is warranted.     

Final DSM-5 under-identifies mild Autism Spectrum Disorder: Agreement between the DSM-5, CARS,CASD, and clinical diagnoses

Agreement between the final DSM-5 ASD criteria, Childhood Autism Rating Scale (CARS), and Checklist for Autism Spectrum Disorder (CASD) was assessed in 143 children with ASD and other disorders (e.g., ADHD, intellectual disability, and oppositional defiant disorder). Diagnostic agreement between the CARS and CASD was high (94%), but their agreement with the DSM-5 was lower (84% and 88%). Agreement between the DSM-5 and both the CARS and CASD increased to 94% and diagnostic accuracy increased from 92% to 96% when one less DSM-5 social communication and interaction symptom was required for a diagnosis. Children with ASD not meeting DSM-5 criteria most often did not have criterion A2 (deficits in nonverbal social communication). Total scores on the DSM-5, CASD, and CARS were far higher for children with mild ASD (formerly PDDNOS) than no ASD, indicating that these children are clearly on the autism spectrum and are quite different from children with other disorders. However, only one child with mild ASD was identified by the DSM-5. This study and 11 others show that the DSM-5 under-identifies children with ASD, particularly children at the mild end of the spectrum. This can be rectified by requiring one less social communication and interaction symptom for a diagnosis.     

Cognitive and emotional intelligence in young adults with Autism Spectrum Disorder without an accompanying intellectual or language disorder

Research in the neurosciences has identified distinctions between neural structures that subserve cognitive intelligence (CI) and those subserving emotional intelligence (EI). This study explored the performance of young adults with Autism Spectrum Disorder (ASD) without an accompanying intellectual or language disorder relative to typically-developing peers, on indices of CI and EI. Both the ASD and age- and sex-matched typically-developing groups exhibited high average cognitive intellectual abilities. In contrast, the ASD group reported lower levels of EI relative to their typically-developing peers, as expected given the social and emotional challenges faced by individuals with ASD. Importantly, cognitive intelligence did not correlate with EI in either group. Taken together, these findings further support the theory of dissociable neural systems underlying CI and EI. These findings also highlight the need to address not only the intellectual aspects of cognition, but also the emotional components to increase understanding of, and improve treatment for individuals on the autism spectrum. This understanding would enhance our ability to assess and support young adults with ASD, and ultimately ease their transition into adulthood.     

Sleep in adults with Autism Spectrum Disorder: a systematic review and meta-analysis of subjective and objective studies

Background/ObjectiveSleep problems are commonly reported by individuals with Autism Spectrum Disorder (ASD). However, to date, no quantitative evidence synthesis of available studies has been performed to quantify sleep alterations in adults with ASD. We performed a systematic review and meta-analysis of objective (ie, based on actigraphy or polysomnography [PSG]) and subjective (ie, based on sleep diaries/questionnaires) studies comparing sleep parameters in adults with ASD and in a typically developing (TD) control group.MethodsPubMed, OVID databases and Web of Knowledge were systematically searched up to February 2019 with no language restrictions. Original studies including adults with a diagnosis of ASD according to DSM, ICD, or based on standard diagnostic tools (eg, ADOS), and a TD control group were included. Random-effects models were used. Study quality was evaluated with the Newcastle Ottawa Scale (NOS). Analyses were conducted using Comprehensive Meta-Analysis.ResultsFrom initial pool of 1948 references, 14 publications including 8 datasets, (194 ASD and 277 controls) met the inclusion criteria. Compared to controls, individuals with ASD were significantly more impaired in six out of 11 subjective parameters, including lower sleep efficiency (SE, SMD = −0.87, CI = −1.14 – 0.60) and in 10 out of 17 objective outcomes, including longer sleep onset latency (PSG) (SMD = 0.86, CI = 0.29–1.07) and wake after sleep onset (WASO, actigraphy) (SMD = 0.57, CI = 0.28–0.87). The mean NOS score was 4.88/6.ConclusionsIndividuals with ASD demonstrated impaired sleep compared to controls in most subjective and objective measures.     

A comparative study of sensory processing in children with and without Autism Spectrum Disorder in the home and classroom environments

Sensory processing and higher integrative functions impairments are highly prevalent in children with ASD. Context should be considered in analyzing the sensory profile and higher integrative functions. The main objective of this study is to compare sensory processing, social participation and praxis in a group of 79 children (65 males and 14 females) from 5 to 8 years of age (M = 6.09) divided into two groups: ASD Group (n = 41) and Comparison Group (n = 38). The Sensory Processing Measure (SPM) was used to evaluate the sensory profile of the children: parents reported information about their children's characteristics in the home environment, and teachers reported information about the same characteristics in the classroom environment. The ASD Group obtained scores that indicate higher levels of dysfunction on all the assessed measures in both environments, with the greatest differences obtained on the social participation and praxis variables. The most affected sensory modalities in the ASD Group were hearing and touch. Only in the ASD Group were significant differences found between the information reported by parents and what was reported by teachers: specifically, the teachers reported greater dysfunction than the parents in social participation (p = .000), touch (p = .003) and praxis (p = .010). These results suggest that the context-specific qualities found in children with ASD point out the need to receive information from both parents and teachers during the sensory profile assessment process, and use context-specific assessments.     

Prenatal,perinatal and neonatal risk factors of Autism Spectrum Disorder: A comprehensive epidemiological assessment from India

Incidence of Autism Spectrum Disorder (ASD) is increasing across the globe and no data is available from India regarding the risk factors of ASD. In this regard a questionnaire based epidemiological assessment was carried out on prenatal, perinatal and neonatal risk factors of ASD across 8 cities in India. A retrospective cohort of 942 children was enrolled for the study. 471 children with ASD, under age of 10, were analyzed for pre-, peri-, and neonatal factors and were compared with the observations from equal number of controls. The quality control of the questionnaire and data collection was done thoroughly and the observations were computed statistically. A total of 25 factors were evaluated by unadjusted and adjusted analysis in this study. Among the prenatal factors considered, advanced maternal age, fetal distress and gestational respiratory infections were found to be associated with ASD and had an odds ratio of 1.8. Evaluation of perinatal and neonatal risk factors showed labor complications, pre-term birth, neonatal jaundice, delayed birth cry and birth asphyxia to be associated with ASD with an odds ratio greater than 1.5. This important study, first of its kind in Indian population gives a firsthand account of the relation of pre-, peri- and neonatal risk factors on ASD from an ethnically and socially diverse country like India, the impact of which was unknown earlier. This advocates additional focused investigations on physiological and genetic changes contributed by these risk factor inducing environments.     

Sensory processing in children with Autism Spectrum Disorder: Relationship with non-verbal IQ,autism severity and Attention Deficit/Hyperactivity Disorder symptomatology

The main objective of this study was to analyze in a sample of children with ASD the relationship between sensory processing, social participation and praxis impairments and some of the child's characteristics, such as non-verbal IQ, severity of ASD symptoms and the number of ADHD symptoms (inattention and hyperactivity/impulsivity), both in the home and main-classroom environments. Participants were the parents and teachers of 41 children with ASD from 5 to 8 years old (M = 6.09). They completed the Sensory Processing Measure (SPM) to evaluate sensory processing, social participation and praxis; the Gilliam Autism Rating Scale (GARS-2) to evaluate autism severity; and a set of items (the DSM-IV-TR criteria) to evaluate the number of inattention and hyperactivity/impulsivity symptoms in the child. Non-verbal IQ – measured by the Raven's Coloured Progressive Matrices Test – did not show a relationship with any of the SPM variables. The SPM variables were significant predictors of autism severity and had similar weights in the two environments. In the case of ADHD symptoms, the SPM variables had a greater weight in the home than in the classroom environment, and they were significant predictors of both inattention and hyperactivity/impulsivity – especially inattention – only in the family context. The moderate association between inattention and auditory processing found in the main-classroom suggests the possible utility of certain measures aimed to simplify any classroom's acoustic environment.     

An investigation of the effectiveness of Behavioral Momentum on the acquisition and fluency outcomes of tacts in three children with Autism Spectrum Disorder

The study aimed to evaluate the effectiveness of the fluency intervention, Behavioral Momentum (BM), on acquisition of tacts and associated fluency outcomes in three children with Autism Spectrum Disorder (ASD). A multiple probe design across stimulus sets was utilized to investigate the outcomes of Behavioral Momentum for the acquisition, retention, stability, endurance, and application of tacts learned to a fluency aim. In the intervention phase, children were required to complete a Behavioral Momentum exercise consisting of the presentation of a sequence of high probability tacts followed immediately by the presentation of low probability tacts delivered within 1 min timings. The results demonstrated positive fluency outcomes on low probability tacts across all children. The practical implications of the study are discussed in terms of the use of Fluency Training for children with ASD within the educational setting.     

Role of fruits,grains, and seafood consumption in blood cadmium concentrations of Jamaican children with and without Autism Spectrum Disorder

Human exposure to cadmium has adverse effects on the nervous system. Utilizing data from 110 age- and sex-matched case–control pairs (220 children) ages 2–8 years in Kingston, Jamaica, we compared the 75th percentile of blood cadmium concentrations in children with and without Autism Spectrum Disorder (ASD). In both univariable and multivariable Quantile Regression Models that controlled for potential confounding factors, we did not find any significant differences between ASD cases and typically developing (TD) controls with respect to the 75th percentile of blood cadmium concentrations (P > 0.22). However, we found a significantly higher 75th percentile of blood cadmium concentrations in TD Jamaican children who consumed shellfish (lobsters, crabs) (P < 0.05), fried plantain (P < 0.01), and boiled dumpling (P < 0.01). We also observed that children living in Jamaica have an arithmetic mean blood cadmium concentration of 0.16 μg/L which is similar to that of the children in developed countries and much lower than that of children in developing countries. Although our results do not support an association between blood cadmium concentrations and ASD, to our knowledge, this study is the first to report levels of blood cadmium in TD children as well as those with ASD in Jamaica.