1. Adviento B, Corbin IL, Widjaja F, Desachy G, Enrique N, Rosser T, Risi S, Marco EJ, Hendren RL, Bearden CE, Rauen KA, Weiss LA. {{Autism traits in the RASopathies}}. {Journal of medical genetics}. 2013 Oct 7.
BACKGROUND: Mutations in Ras/mitogen-activated protein kinase (Ras/MAPK) pathway genes lead to a class of disorders known as RASopathies, including neurofibromatosis type 1 (NF1), Noonan syndrome (NS), Costello syndrome (CS), and cardio-facio-cutaneous syndrome (CFC). Previous work has suggested potential genetic and phenotypic overlap between dysregulation of Ras/MAPK signalling and autism spectrum disorders (ASD). Although the literature offers conflicting evidence for association of NF1 and autism, there has been no systematic evaluation of autism traits in the RASopathies as a class to support a role for germline Ras/MAPK activation in ASDs. METHODS: We examined the association of autism traits with NF1, NS, CS and CFC, comparing affected probands with unaffected sibling controls and subjects with idiopathic ASDs using the qualitative Social Communication Questionnaire (SCQ) and the quantitative Social Responsiveness Scale (SRS). RESULTS: Each of the four major RASopathies showed evidence for increased qualitative and quantitative autism traits compared with sibling controls. Further, each RASopathy exhibited a distinct distribution of quantitative social impairment. Levels of social responsiveness show some evidence of correlation between sibling pairs, and autism-like impairment showed a male bias similar to idiopathic ASDs. CONCLUSIONS: Higher prevalence and severity of autism traits in RASopathies compared to unaffected siblings suggests that dysregulation of Ras/MAPK signalling during development may be implicated in ASD risk. Evidence for sex bias and potential sibling correlation suggests that autism traits in the RASopathies share characteristics with autism traits in the general population and clinical ASD population and can shed light on idiopathic ASDs.
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2. Brock J. {{Connectivity and cognition in autism spectrum disorders: Where are the links?}}. {Proceedings of the National Academy of Sciences of the United States of America}. 2013 Oct 7.
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3. Herbert MR, Sage C. {{Autism and EMF? Plausibility of a pathophysiological link part II}}. {Pathophysiology : the official journal of the International Society for Pathophysiology / ISP}. 2013 Oct 7.
Autism spectrum conditions (ASCs) are defined behaviorally, but they also involve multileveled disturbances of underlying biology that find striking parallels in the physiological impacts of electromagnetic frequency and radiofrequency radiation exposures (EMF/RFR). Part I (Vol 776) of this paper reviewed the critical contributions pathophysiology may make to the etiology, pathogenesis and ongoing generation of behaviors currently defined as being core features of ASCs. We reviewed pathophysiological damage to core cellular processes that are associated both with ASCs and with biological effects of EMF/RFR exposures that contribute to chronically disrupted homeostasis. Many studies of people with ASCs have identified oxidative stress and evidence of free radical damage, cellular stress proteins, and deficiencies of antioxidants such as glutathione. Elevated intracellular calcium in ASCs may be due to genetics or may be downstream of inflammation or environmental exposures. Cell membrane lipids may be peroxidized, mitochondria may be dysfunctional, and various kinds of immune system disturbances are common. Brain oxidative stress and inflammation as well as measures consistent with blood-brain barrier and brain perfusion compromise have been documented. Part II of this paper documents how behaviors in ASCs may emerge from alterations of electrophysiological oscillatory synchronization, how EMF/RFR could contribute to these by de-tuning the organism, and policy implications of these vulnerabilities. It details evidence for mitochondrial dysfunction, immune system dysregulation, neuroinflammation and brain blood flow alterations, altered electrophysiology, disruption of electromagnetic signaling, synchrony, and sensory processing, de-tuning of the brain and organism, with autistic behaviors as emergent properties emanating from this pathophysiology. Changes in brain and autonomic nervous system electrophysiological function and sensory processing predominate, seizures are common, and sleep disruption is close to universal. All of these phenomena also occur with EMF/RFR exposure that can add to system overload (‘allostatic load’) in ASCs by increasing risk, and can worsen challenging biological problems and symptoms; conversely, reducing exposure might ameliorate symptoms of ASCs by reducing obstruction of physiological repair. Various vital but vulnerable mechanisms such as calcium channels may be disrupted by environmental agents, various genes associated with autism or the interaction of both. With dramatic increases in reported ASCs that are coincident in time with the deployment of wireless technologies, we need aggressive investigation of potential ASC-EMF/RFR links. The evidence is sufficient to warrant new public exposure standards benchmarked to low-intensity (non-thermal) exposure levels now known to be biologically disruptive, and strong, interim precautionary practices are advocated.
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4. Karvat G, Kimchi T. {{Acetylcholine Elevation Relieves Cognitive Rigidity and Social Deficiency in a Mouse Model of Autism}}. {Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology}. 2013 Oct 7.
Autism spectrum disorders (ASD) is defined by behavioral deficits in social interaction, communication, repetitive stereotyped behaviors and restricted interests/ cognitive rigidity. Recent studies in humans and mice suggested that dysfunction of the cholinergic system may underlie autism-related behavioral symptoms. Here we tested the hypothesis that augmentation of acetylcholine in the synaptic cleft by inhibiting acetylcholinesterase may ameliorate autistic phenotypes. We first administered the acetylcholinesterase inhibitor (AChEI) Donepezil systemically by intraperitoneal (i.p.) injections. Second, the drug was injected directly into the rodent homologue of the caudate nucleus, the dorso-medial-striatum (DMS), of the inbred mouse strain BTBR T+tf/J (BTBR), a commonly-used model presenting all core autism-related phenotypes and expressing low brain acetylcholine levels. We found that i.p. injection of AChEI to BTBR mice significantly relieved autism-relevant phenotypes, including decreasing cognitive rigidity, improving social preference and enhancing social interaction, in a dose dependent manner. Microinjection of the drug directly into the DMS, but not into the ventromedial striatum, led to significant amelioration of the cognitive-rigidity and social-deficiency phenotypes. Taken together, these findings provide evidence of the key role of the cholinergic system and the DMS in the etiology of ASD, and suggest that elevated cognitive flexibility may result in enhanced social attention. The potential therapeutic effect of AChEIs in ASD patients is discussed.Neuropsychopharmacology accepted article preview online, 7 October 2013. doi:10.1038/npp.2013.274.
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5. Leonard HC, Bedford R, Charman T, Elsabbagh M, Johnson MH, Hill EL, The Bt. {{Motor development in children at risk of autism: A follow-up study of infant siblings}}. {Autism}. 2013 Oct 7.
Recently, evidence of poor or atypical motor skills in autism spectrum disorder has led some to argue that motor impairment is a core feature of the condition. The current study uses a longitudinal prospective design to assess the development of motor skills of 20 children at increased risk of developing autism spectrum disorder, who were recruited and tested at 9 and 40 months of age, on the basis of having an older sibling diagnosed with the condition. All children completed a range of motor, face processing, IQ and diagnostic assessments at a follow-up visit (aged 5-7 years), providing a detailed profile of development in this group from a number of standardised, parental report and experimental measures. A higher proportion of children than expected demonstrated motor difficulties at the follow-up visit and those highlighted by parental report as having poor motor skills as infants and toddlers were also more likely to have lower face processing scores and elevated autism-related social symptoms at 5-7 years, despite having similar IQ levels. These data lend support to the argument that early motor difficulties may be a risk factor for later motor impairment as well as differences in social communication and cognition, traits that are related to autism spectrum disorder.
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6. McConachie H, McLaughlin E, Grahame V, Taylor H, Honey E, Tavernor L, Rodgers J, Freeston M, Hemm C, Steen N, Le Couteur A. {{Group therapy for anxiety in children with autism spectrum disorder}}. {Autism}. 2013 Oct 7.
Aim:To investigate the acceptability and feasibility of adapted group therapy for anxiety in children with autism spectrum disorder in a pilot randomised controlled trial.Method:A total of 32 children aged 9-13 years were randomised to immediate or delayed therapy using the ‘Exploring Feelings’ manual (Attwood, 2004). Child and parent groups were run in parallel, for seven weekly sessions, under the supervision of experienced psychologists. The primary blinded outcome measures addressed change in overall functioning and in severity of the primary anxiety diagnosis after 3 months.Results:Children met diagnostic criteria for 1-6 anxiety disorders (median 3). At end point, both parents and children in the immediate therapy group were more likely to report a reduction in anxiety symptoms. Fidelity of delivery of the group therapy was high, and attendance was 91%.Conclusions:This pilot trial established that children and families were willing to be recruited and randomised, the outcome measures were acceptable, the format and content of the groups were feasible within UK child and adolescent mental health services, the intervention was appreciated by families and attrition was very small.
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7. Plavnick JB, Hume KA. {{Observational learning by individuals with autism: A review of teaching strategies}}. {Autism}. 2013 Oct 7.
Observational learning is the process used to explain the acquisition of novel behaviors or performance of previously acquired behaviors under novel conditions after observing the behavior of another person and the consequences that follow the behavior. Many learners with autism do not attend to environmental stimuli at a level sufficient to learn a range of prosocial behaviors through observation of others. Modeling, group or dyadic instruction, and explicit observation training can improve the extent to which individuals with autism learn through observation. This article reviews previous research that involved observational learning by individuals with autism and outlines future research that could benefit instructional practices.
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8. Sharp WG, Burrell TL, Jaquess DL. {{The Autism MEAL Plan: A parent-training curriculum to manage eating aversions and low intake among children with autism}}. {Autism}. 2013 Oct 7.
Feeding problems represent a frequent concern reported by caregivers of children with autism spectrum disorders, and growing evidence suggests atypical patterns of intake may place this population at risk of nutritional and/or related medical issues, including chronic vitamin and mineral deficiencies, poor bone growth, and obesity. This combination of factors emphasizes a clear need to identify and disseminate evidence-based treatment of feeding problems associated with autism spectrum disorders. Behavioral intervention represents an effective treatment for chronic feeding concerns in this population; however, evidence has largely been established with trained therapists working in highly structured settings. This pilot study seeks to fill this gap in the literature by describing and evaluating the Autism MEAL Plan, a behaviorally based parent-training curriculum to address feeding problems associated with autism spectrum disorders. We assessed the feasibility of the intervention in terms of program content and study protocol (e.g. recruitment and retention of participants, assessment procedures), as well as efficacy in terms of changes in feeding behaviors. A total of 10 families participated in the treatment condition, and the program was evaluated using a waitlist control design (n = 9), representing the first randomized-control study of a feeding intervention in autism spectrum disorders. Results provide provisional support regarding the utility of the program, including high social validity, parent perception of effectiveness, and reduced levels of caregiver stress following intervention. Implications, limitations, and future directions for this line of research are discussed.
