1. Alant E, Zheng W, Harty M, Lloyd L. {{Translucency Ratings of Blissymbols over Repeated Exposures by Children with Autism}}. {Augment Altern Commun};2013 (Jul 31)
The use of graphic symbols forms an integral part of augmentative and alternative communication (AAC) strategies, particularly for pre-literate children. Although some studies have indicated that typically developing children and those with autism are able to learn symbol meanings with multiple exposures to graphic symbols, little is known about how children with autism rate the degree to which the symbol represents its referent (translucency) with repeated exposures. The purpose of this study was to describe the translucency ratings of children with autism over three consecutive exposures. Twenty-two children with autism participated in a Blissymbol translucency task that included 40 symbols. The Blissymbol task was modified from Bornman, Alant, and du Preez (2009) , who explored the translucency of Blissymbols with typically developing children. Findings of this study indicated statistically significant differences in total translucency ratings of the Blissymbols by the children with autism between Day 1 and Day 3 (medium effect size) with Day 3 yielding more positive ratings than Day 1. No single Blissymbol showed statistically significant differences over the days. Findings are interpreted and further implications for research are discussed.
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2. Cardinale RC, Shih P, Fishman I, Ford LM, Muller RA. {{Pervasive Rightward Asymmetry Shifts of Functional Networks in Autism Spectrum Disorder}}. {JAMA Psychiatry};2013 (Jul 31)
IMPORTANCE Autism spectrum disorder (ASD) is a brain-based pervasive developmental disorder, which-by growing consensus-is associated with abnormal organization of functional networks. Several previous studies of ASD have indicated atypical hemispheric asymmetries for language. OBJECTIVE To examine the asymmetry of functional networks using a data-driven approach for a comprehensive investigation of hemispheric asymmetry in ASD. DESIGN, SETTING, AND PARTICIPANTS This cross-sectional study involved 24 children with ASD and 26 matched typically developing children at San Diego State University and the University of California, San Diego. Data from 10 children had to be excluded for excessive motion, resulting in final samples of 20 participants per group. MAIN OUTCOMES AND MEASURES Asymmetry indices of functional networks identified from independent component analysis of resting-state functional magnetic resonance imaging data. RESULTS Temporal concatenation independent component analysis, performed separately in each group, showed significant group differences in asymmetry indices for 10 out of 17 functional networks. Without exception, these networks (visual, auditory, motor, executive, language, and attentional) showed atypical rightward asymmetry shifts in the ASD group. CONCLUSIONS AND RELEVANCE Atypical rightward asymmetry may be a pervasive feature of functional brain organization in ASD, affecting sensorimotor, as well as higher cognitive, domains.
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3. Corrigan NM, Shaw DW, Estes AM, Richards TL, Munson J, Friedman SD, Dawson G, Artru AA, Dager SR. {{Atypical Developmental Patterns of Brain Chemistry in Children With Autism Spectrum Disorder}}. {JAMA Psychiatry};2013 (Jul 31)
IMPORTANCE Autism spectrum disorder (ASD) is a neurodevelopmental disorder with symptoms emerging during early childhood. The pathophysiology underlying the disorder remains incompletely understood. OBJECTIVE To examine cross-sectional and longitudinal patterns of brain chemical concentrations in children with ASD or idiopathic developmental delay (DD) from 3 different age points, beginning early in the clinical course. DESIGN Proton magnetic resonance spectroscopic imaging data were acquired longitudinally for children with ASD or DD, and primarily cross-sectionally for children with typical development (TD), at 3 to 4, 6 to 7, and 9 to 10 years of age. SETTING Recruitment, diagnostic assessments, and magnetic resonance imaging were performed at the University of Washington in Seattle. PARTICIPANTS Seventy-three children (45 with ASD, 14 with DD, and 14 with TD) at 3 to 4 years of age; 69 children (35 with ASD, 14 with DD, and 20 with TD) at 6 to 7 years of age; and 77 children (29 with ASD, 15 with DD, and 33 with TD) at 9 to 10 years of age. MAIN OUTCOMES AND MEASURES Concentrations of N-acetylaspartate (NAA), choline (Cho), creatine (Cr), myo-inositol (mI), and glutamine plus glutamate (Glx) in cerebral gray matter (GM) and white matter (WM) at 3 to 4, 6 to 7, and 9 to 10 years of age, and calculation of rates of change of these chemicals between 3 and 10 years of age. RESULTS At 3 to 4 years of age, the ASD group exhibited lower NAA, Cho, and Cr concentrations than did the TD group in both GM and WM, alterations that largely were not observed at 9 to 10 years of age. The DD group exhibited reduced GM and WM NAA concentrations at 3 to 4 years of age; GM NAA concentrations remained reduced at 9 to 10 years of age compared with the TD group. There were distinct differences between the ASD and DD groups in the rates of GM NAA, Cho, and Cr changes between 3 and 10 years of age. CONCLUSIONS AND RELEVANCE The GM chemical changes between 3 and 10 years of age differentiated the children with ASD from those with DD. Most notably, a dynamic reversal of GM NAA reductions was observed in the children with ASD. By contrast, persistent GM NAA reductions in the children with DD suggest a different, more static, underlying developmental process.
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4. Duffy FH, Shankardass A, McAnulty GB, Als H. {{The relationship of Asperger’s syndrome to autism: a preliminary EEG coherence study}}. {BMC Med};2013;11:175.
BACKGROUND: It has long been debated whether Asperger’s Syndrome (ASP) should be considered part of the Autism Spectrum Disorders (ASD) or whether it constitutes a unique entity. The Diagnostic and Statistical Manual, fourth edition (DSM-IV) differentiated ASP from high functioning autism. However, the new DSM-5 umbrellas ASP within ASD, thus eliminating the ASP diagnosis. To date, no clear biomarkers have reliably distinguished ASP and ASD populations. This study uses EEG coherence, a measure of brain connectivity, to explore possible neurophysiological differences between ASP and ASD. METHODS: Voluminous coherence data derived from all possible electrode pairs and frequencies were previously reduced by principal components analysis (PCA) to produce a smaller number of unbiased, data-driven coherence factors. In a previous study, these factors significantly and reliably differentiated neurotypical controls from ASD subjects by discriminant function analysis (DFA). These previous DFA rules are now applied to an ASP population to determine if ASP subjects classify as control or ASD subjects. Additionally, a new set of coherence based DFA rules are used to determine whether ASP and ASD subjects can be differentiated from each other. RESULTS: Using prior EEG coherence based DFA rules that successfully classified subjects as either controls or ASD, 96.2% of ASP subjects are classified as ASD. However, when ASP subjects are directly compared to ASD subjects using new DFA rules, 92.3% ASP subjects are identified as separate from the ASD population. By contrast, five randomly selected subsamples of ASD subjects fail to reach significance when compared to the remaining ASD populations. When represented by the discriminant variable, both the ASD and ASD populations are normally distributed. CONCLUSIONS: Within a control-ASD dichotomy, an ASP population falls closer to ASD than controls. However, when compared directly with ASD, an ASP population is distinctly separate. The ASP population appears to constitute a neurophysiologically identifiable, normally distributed entity within the higher functioning tail of the ASD population distribution. These results must be replicated with a larger sample given their potentially immense clinical, emotional and financial implications for affected individuals, their families and their caregivers.
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5. Lessmann J, Sarimski K. {{[Family experiences with the diagnosis of fragile X syndrome–results of a retrospective parental survey]}}. {Prax Kinderpsychol Kinderpsychiatr};2013;62(6):420-434.
Family X syndrome is the second most common inherited form of mental retardation. The suspected diagnosis is made on a characteristic behavioral phenotype and confirmed by genetic analysis. In a retrospective survey, 57 parents report on the process of diagnosis. The mean age of diagnosed children was 4;8 years. A majority of two thirds of parents stated that knowledge of the cause of the disorder was important to them. At the same time many parents felt the process was insensitive and missed specific information on developmental perspectives for their children. Most say they benefited from the national parent self-help group as an important resource of support. Conclusions for professional support for parents are discussed.
6. Thistle JJ, Wilkinson KM. {{Working Memory Demands of Aided Augmentative and Alternative Communication for Individuals with Developmental Disabilities}}. {Augment Altern Commun};2013 (Jul 31)
When speech is not functional to meet some or all of an individual’s communication needs, aided augmentative and alternative communication (AAC) systems are often implemented. Although aided AAC systems offer some advantages over speech, they also impose some unique demands, especially on working memory, which is commonly defined as the cognitive system by which individuals maintain and manipulate information while completing tasks. For instance, the presence of an external aided AAC device containing arrays of symbols, not all of which are visible simultaneously, presents multiple working memory demands: individuals must maintain the target concepts in mind, all the while (a) navigating through multiple pages, (b) remembering the appropriate or most efficient navigation path, (c) locating the target symbols within the array once the host page has been located, and (d) inhibiting responses to potentially interesting distracters throughout the process. Each of these task demands involves one or more working memory operations that have been identified and studied extensively in research in the cognitive sciences. Failure to acknowledge or understand how working memory might interact with AAC use may place unintentional barriers to effective AAC interventions. This paper explores current information about working memory operations and highlights some of the most relevant issues that warrant further direct study.
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7. Venker CE, Ray-Subramanian CE, Bolt DM, Weismer SE. {{Trajectories of Autism Severity in Early Childhood}}. {J Autism Dev Disord};2013 (Aug 2)
Relatively little is known about trajectories of autism severity using calibrated severity scores (CSS) from the Autism Diagnostic Observation Schedule, but characterizing these trajectories has important theoretical and clinical implications. This study examined CSS trajectories during early childhood. Participants were 129 children with autism spectrum disorder evaluated annually from ages 2(1/2) to 5(1/2). The four severity trajectory classes that emerged-Persistent High (n = 47), Persistent Moderate (n = 54), Worsening (n = 10), and Improving (n = 18)-were strikingly similar to those identified by Gotham et al. (Pediatrics 130(5):e1278-e1284, 2012). Children in the Persistent High trajectory class had the most severe functional skill deficits in baseline nonverbal cognition and daily living skills and in receptive and expressive language growth.
