Physical exercise and individuals with autism spectrum disorders: A systematic review

Studies involving physical exercise and individuals with autism spectrum disorders (ASD) were reviewed. Systematic search procedures identified 18 studies meeting predetermined inclusion criteria. These studies were evaluated in terms of: (a) participant characteristics, (b) type of exercise, (c) procedures used to increase exercise, (d) outcomes, and (e) research methodology. Across the corpus of studies, exercise was implemented with 64 participants with ASD aged 3–41 years. A variety of exercise activities were employed (e.g., jogging, weight training, bike riding). Following the exercise interventions decreases in stereotypy, aggression, off-task behavior and elopement were reported. Fatigue was not likely the cause of decreases in maladaptive behavior because on-task behavior, academic responding, and appropriate motor behavior (e.g., playing catch) increased following physical exercise. Results suggest that programs for individuals with ASD may benefit from including components designed to incorporate regular and specific types of physical activity. Areas in need of further research are discussed.     

Neurofeedback in autism spectrum disorders

Aim  To review current studies on the effectiveness of neurofeedback as a method of treatment of the core symptoms of autism spectrum disorders (ASD). Method  Studies were selected based on searches in PubMed, Ovid MEDLINE, EMBASE, ERIC, and CINAHL using combinations of the following keywords: ‘Neurofeedback’ OR ‘EEG Biofeedback’ OR ‘Neurotherapy’ OR ‘Mu‐Rhythm’ OR ‘SMR’ AND ‘Autism’ OR ‘Autism Spectrum Disorder’ OR ‘Pervasive Developmental Disorder’. Results  The existing evidence does not support the use of neurofeedback in the treatment of ASD. Studies with outcomes in favour of neurofeedback might be showing an improvement in comorbid attention‐deficit–hyperactivity disorder symptoms rather than a true improvement in core ASD symptoms. Interpretation  Limitations of this review are those inherent in the studies available, including small sample size, short duration, variable diagnostic criteria, and insufficient control interventions, all causing a lack of generalizability.     

Epilepsy in autism spectrum disorders

Epilepsy is quite common in autism spectrum disorders, and it is increasingly recognized as an additional clinical problem that must be dealt with. The rate of comorbidity varies, depending upon the age and type of disorder, and currently the conservative estimate of comorbidity cases is 20–25% of the whole spectrum. Major risk factors for seizure occurrence are mental retardation and additional neurological disorders, as well as some specific associated medical conditions. Autism with regression has been reported in one-third of children with previously normal or nearly normal development. In an unknown proportion of these subjects, epileptic disorders are concomitant, leading to so-called autistic epileptiform regression. Furthermore, epileptiform abnormalities without seizures are frequent in this population and their role in the development of the nuclear disturbances of autism is controversial. The therapeutic approaches to epilepsy in autism are conventional treatments, yet when seizures are not evident, there is still controversy. Anticonvulsant medications could also potentially interfere with mood and behavioral disturbances frequently observed in ASD. The current understanding of the association between epilepsy and autism is still limited, but from a clinical point of view this association should not be overlooked, and it should be routinely investigated.     

Evidence-based practice: A quality indicator analysis of peer-tutoring in adapted physical education

The purpose of the research was to conduct a quality indicator analysis of studies investigating peer-tutoring for students with a disability in adapted physical education. An electronic search was conducted among English journals published from 1960 to November 2012. Databases included ERIC, PsycINFO, and SPORTDiscus. Fifteen research studies employing group-experimental (Gersten et al., 2005) or single-subject designs (Horner et al., 2005) met inclusion criteria. Each study was assessed for the presence and clarity of quality indicators. Group designs met an average of 62.5% essential and 69% desirable indicators. An average of 80% of indicators was present for single-subject designs. Results suggest claims of peer-tutoring being an evidence-based practice are premature. Recommendations for clarifying and applying the quality indicators are offered.     

Pharmacotherapy of autism spectrum disorders

Although no pharmacological or behavioral therapy has currently proven effective for treating all core symptoms of autism, many dysfunctional behaviors may be treated pharmacologically. Drug treatments should always be part of a comprehensive management plan that includes behavioral and educational interventions, and should be focused on specific targets. Several classes of psychotropic medications have been used to decrease the wide range of “maladaptive” or “interfering” behaviors and associated medical problems that can interfere with relationships and physical health and hinder the implementation of various non-pharmacological interventions. Atypical neuroleptics have been shown to be useful in the treatment of behavioral symptoms in autism. Attention deficit and hyperactivity disorder medications may be effective for counteracting the additional features of hyperactivity and short attention span. Antiepileptic drugs and selective serotonin reuptake inhibitors have shown promising results, but there are no specific indications for them as of yet. With respect to potential drug targets, some clinical features are caused by a dysfunction in neurochemical signaling systems, and thus may improve with selective pharmacological interventions acting on specific abnormal neurobiological pathways. Recent animal studies can be useful models for understanding the common pathogenic pathways leading to autism spectrum disorders (ASDs), and have the potential to offer new biologically focused treatment options.     

Genetics of autism spectrum disorders

Autism spectrum disorders (ASDs) are a clinically complex group of childhood disorders that have firm evidence of an underlying genetic etiology. Many techniques have been used to characterize the genetic bases of ASDs. Linkage studies have identified several replicated susceptibility loci, including 2q24–2q31, 7q, and 17q11–17q21. Association studies and mutation analysis of candidate genes have implicated the synaptic genes NRXN1, NLGN3, NLGN4, SHANK3, and CNTNAP2 in ASDs. Traditional cytogenetic approaches highlight the high frequency of large chromosomal abnormalities (3%–7% of patients), including the most frequently observed maternal 15q11–13 duplications (1%–3% of patients). Newly developed techniques include high-resolution DNA microarray technologies, which have discovered formerly undetectable submicroscopic copy number variants, and genomewide association studies, which allow simultaneous detection of multiple genes associated with ASDs. Although great progress has been made in autism genetics, the molecular bases of most ASDs remains enigmatic.     

Face-brain asymmetry in autism spectrum disorders

The heterogeneity of autism spectrum disorders (ASDs) confounds attempts to identify causes and pathogenesis. Identifiable endophenotypes and reliable biomarkers within ASDs would help to focus molecular research and uncover genetic causes and developmental mechanisms. We used dense surface-modelling techniques to compare the facial morphology of 72 boys with ASD and 128 first-degree relatives to that of 254 unrelated controls. Pattern-matching algorithms were able to discriminate between the faces of ASD boys and those of matched controls (AUC=0.82) and also discriminate between the faces of unaffected mothers of ASD children and matched female controls (AUC=0.76). We detected significant facial asymmetry in boys with ASD (P<0.01), notably depth-wise in the supra- and periorbital regions anterior to the frontal pole of the right hemisphere of the brain. Unaffected mothers of children with ASD display similar significant facial asymmetry, more exaggerated than that in matched controls (P<0.03) and, in particular, show vertical asymmetry of the periorbital region. Unaffected fathers of children with ASD did not show facial asymmetry to a significant degree compared to controls. Two thirds of unaffected male siblings tested were classified unseen as more facially similar to unrelated boys with ASD than to unrelated controls. These unaffected male siblings and two small groups of girls with ASD and female siblings, all show overall directional asymmetry, but without achieving statistical significance in two-tailed t-tests of individual asymmetry of ASD family and matched control groups. We conclude that previously identified right dominant asymmetry of the frontal poles of boys with ASD could explain their facial asymmetry through the direct effect of brain growth. The atypical facial asymmetry of unaffected mothers of children with ASD requires further brain studies before the same explanation can be proposed. An alternative explanation, not mutually exclusive, is a simultaneous and parallel action on face and brain growth by genetic factors. Both possibilities suggest the need for coordinated face and brain studies on ASD probands and their first-degree relatives, especially on unaffected mothers, given that their unusual facial asymmetry suggests an ASD susceptibility arising from maternal genes.     

Cognitive control in autism spectrum disorders

Cognitive control refers to the ability to flexibly allocate mental resources to guide thoughts and actions in light of internal goals. Given the behavioral inflexibility exhibited by individuals with autism spectrum disorders (ASDs), it would appear they experience cognitive control deficits. Cognitive correlates of this behavioral inflexibility have been elusive in previous investigations. Study goals were to investigate deficits in cognitive control in ASDs; to explore its developmental trajectory; and to test whether control deficits are related to symptoms of inflexible thoughts and/or behaviors, and attention symptoms. Thirty-one children and adolescents aged 8-17 with ASDs and 32 age, IQ, and gender matched control subjects completed cognitive, diagnostic, and behavorial assessments, as well as a measure of cognitive control involving overcoming a prepotent response tendency. Compared with typically developing control subjects, individuals with ASDs exhibited deficits in cognitive control. Younger children with ASDs did not demonstrate age-related improvements in cognitive control. Modest relationships between cognitive control, IQ, and attention problems were found for the sample. Only the relationship between cognitive control and full-scale IQ survived correction for multiple comparisons.     

Recent advances in autism spectrum disorders

OBJECTIVE: This review article provides an overview of the most recent developments in the literature regarding autism spectrum disorders including epidemiology, etiology, assessment, and management/treatment. METHOD: A review of the recent literature was conducted using Medline and the search term "Autism Spectrum Disorders." RESULTS: Autism Spectrum Disorders are more common than previously believed (1 in 166), and etiology appears to be multifaceted including both heritable and non-heritable factors. State of the art treatment includes comprehensive medical monitoring as well as behavioral intervention. CONCLUSIONS: Current and anticipated federal funding, policy changes, and large scale research projects provide promise for increasing knowledge about Autism Spectrum Disorders.     

An exploration of symmetry in early autism spectrum disorders: analysis of lying

Background: Early identification of children with autism spectrum disorders (ASD) is recognized as a critical aspect of their medical management and treatment. Movement disorders are considered one of the first signs which probably precede social or linguistic abnormalities. Objectives: to verify, through observational methods, the possibility of distinguishing infants with ASD from infants with typical development or with mental retardation by movement. Methods: The Eshkol-Wachman movement analysis system, which analyses static symmetry (SS) and dynamic symmetry (DS) during lying, was applied to retrospective home videos regarding the first 5 months of life of children with ASD (n = 18), typical development (n = 18), or developmental delay (n = 12). Results: Significant differences between ASD and the two control groups were found for both SS (p < .001) and DS (p < .01). Within ASD two groups of infants could be differentiated on the basis of the higher (HLS) or the lower (LLS) levels of symmetry. Early onset ASD are more likely to belong to the LLS group. Conclusion: We suggest that motor functioning may define specific subgroups of early ASD which are related to different pathways to the syndrome. LLS could be used as an early indicator of potential autism since the first months of life.     

Neurometabolic disorders and dysfunction in autism spectrum disorders

The cause of autism remains largely unknown because it is likely multifactorial, arising from the interaction of biologic, genetic, and environmental factors. The specific role of metabolic abnormalities also is largely unknown, but current research may provide insight into the pathophysiologic underpinnings of autism, at least in some patients. We review a number of known neurometabolic disorders identified as having an autistic phenotype. We also discuss the possible involvement of mitochondrial disorders and dysfunction as well as a theory regarding an increased vulnerability to oxidative stress, by which various environmental toxins produce metabolic alterations that impair normal cellular function. Finally, we review various strategies for metabolic work-up and treatment. Accurate diagnosis of neurometabolic disorders and a broader understanding of underlying metabolic disturbance even in the absence of known disease have important implications both for individual patients and for research into the etiology of autism.     

Medical conditions in autism spectrum disorders

Autism spectrum disorder (ASD) is a behaviourally defined syndrome where the etiology and pathophysiology is only partially understood. In a small proportion of children with the condition, a specific medical disorder is identified, but the causal significance in many instances is unclear. Currently, the medical conditions that are best established as probable causes of ASD include Fragile X syndrome, Tuberous Sclerosis and abnormalities of chromosome 15 involving the 15q11-13 region. Various other single gene mutations, genetic syndromes, chromosomal abnormalities and rare de novo copy number variants have been reported as being possibly implicated in etiology, as have several ante and post natal exposures and complications. However, in most instances the evidence base for an association with ASD is very limited and largely derives from case reports or findings from small, highly selected and uncontrolled case series. Not only therefore, is there uncertainty over whether the condition is associated, but the potential basis for the association is very poorly understood. In some cases the medical condition may be a consequence of autism or simply represent an associated feature deriving from an underlying shared etiology. Nevertheless, it is clear that in a growing proportion of individuals potentially causal medical conditions are being identified and clarification of their role in etio-pathogenesis is necessary. Indeed, investigations into the causal mechanisms underlying the association between conditions such as tuberous sclerosis, Fragile X and chromosome 15 abnormalities are beginning to cast light on the molecular and neurobiological pathways involved in the pathophysiology of ASD. It is evident therefore, that much can be learnt from the study of probably causal medical disorders as they represent simpler and more tractable model systems in which to investigate causal mechanisms. Recent advances in genetics, molecular and systems biology and neuroscience now mean that there are unparalleled opportunities to test causal hypotheses and gain fundamental insights into the nature of autism and its development.     

Quality of life for parents of children with autism spectrum disorders

This project describes health-related quality of life (HRQoL) of parents of children with autism spectrum disorders (ASDs) using mixed methods. Parents of children with ASDs (N = 224) reported on their HRQoL, depression, and caregiving burden using quantitative tools. HRQoL scores were slightly worse than from those in normative populations especially related to stress and mental health. For example, parents reported average HRQoL scores from SF-6D of 0.74, which was clinically significant lower than an average normative U.S. population. 40% of parents reported having clinical depression symptoms. Married parents reported lower depression symptoms than parents who were not. In addition, families with three or more children with special health care needs (CSHCN) reported lower HRQL and higher caregiving burden than families with less CSHCN. In the qualitative study, we conducted five focus groups to gain insight as to the reasons a child's ASD might influence a parent's HRQoL. Qualitative data further supports the notion that parental HRQoL was negatively influenced by their child's ASDs. Studies that seek to quantify the influence of ASDs and to assess the effect of interventions for children with ASDs may consider measuring the effects on family members as well.     

Brief report: Psychopharmacology of autism spectrum disorders

The purpose of this paper is to review briefly recent findings on the efficacy of psychopharmacological interventions in autism spectrum disorder, point out gaps in our current knowledge of the effects of specific drug classes, and suggest both general and specific research directions for the future. For a more comprehensive review of drug studies in autism, readers are directed toward McDougle, Price, and Volkmar (1994).     

Prevalence of autism spectrum disorders in China

Autism spectrum disorders （ASD） are a heterogeneous group of neuro-developmental disorders that are among the most genetically heritable behavioral disorders.[1] ASD have attracted increasing attention from researchers and public-health agencies worldwide, particularly in Western high-income nations, where substantial increases in the prevalence of ASD have been reported since the 1990s, and where strong advocacy by families of persons with autism has resulted in increased funding for research into the causes of these devastating conditions. Far fewer data on ASD prevalence are available from Asia than from Europe and North America. Thus, the report in the previous issue by Wan and colleagues,I2] of a comprehensive review and meta- analysis of prevalence estimates for ASD in mainland China, Taiwan, Hong Kong and Macau, is a welcome contribution to the international literature. The results of the study, which focused on analyses of populations 〈 18 years of age, highlight the urgent need for large methodologically rigorous studies of the prevalence of ASD in Han Chinese populations--an ethnic group that includes approximately 20% of the world＇s population.     

The genetics of autism spectrum disorders

Epidemiological twin studies demonstrate that autism spectrum disorders (ASDs) represent genetic disorders. Subsequent analyses indicate that the causes of ASDs include less common single-gene mutations and chromosomal abnormalities, as well as ASDs caused by multiple interacting genes of weak effect. Genome-wide linkage analysis has identified several susceptibility loci for the ASDs, and positional and functional candidate genes have been identified that appear to represent susceptibility genes for the ASDs. Analysis of additional larger samples and the use of genome-wide association and high-throughput variant detection will lead to the identification of further genes for ASDs.