1. Delmonte S, Balsters JH, McGrath J, Fitzgerald J, Brennan S, Fagan AJ, Gallagher L. {{Social and monetary reward processing in autism spectrum disorders}}. {Mol Autism};2012 (Sep 26);3(1):7.
ABSTRACT: BACKGROUND: Social motivation theory suggests that deficits in social reward processing underlie social impairments in autism spectrum disorders (ASD). However, the extent to which abnormalities in reward processing generalize to other classes of stimuli remains unresolved. The aim of the current study was to examine if reward processing abnormalities in ASD are specific to social stimuli or can be generalized to other classes of reward. Additionally, we sought to examine the results in the light of behavioral impairments in ASD. METHODS: Participants performed adapted versions of the social and monetary incentive delay tasks. Data from 21 unmedicated right-handed male participants with ASD and 21 age- and IQ-matched controls were analyzed using a factorial design to examine the blood-oxygen-level-dependent (BOLD) response during the anticipation and receipt of both reward types. RESULTS: Behaviorally, the ASD group showed less of a reduction in reaction time (RT) for rewarded compared to unrewarded trials than the control group. In terms of the fMRI results, there were no significant group differences in reward circuitry during reward anticipation. During the receipt of rewards, there was a significant interaction between group and reward type in the left dorsal striatum (DS). The ASD group showed reduced activity in the DS compared to controls for social rewards but not monetary rewards and decreased activation for social rewards compared to monetary rewards. Controls showed no significant difference between the two reward types. Increased activation in the DS during social reward processing was associated with faster response times for rewarded trials, compared to unrewarded trials, in both groups. This is in line with behavioral results indicating that the ASD group showed less of a reduction in RT for rewarded compared to unrewarded trials. Additionally, de-activation to social rewards was associated with increased repetitive behavior in ASD. CONCLUSIONS: In line with social motivation theory, the ASD group showed reduced activation, compared to controls, during the receipt of social rewards in the DS. Groups did not differ significantly during the processing of monetary rewards. BOLD activation in the DS, during social reward processing, was associated with behavioral impairments in ASD.
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2. Demopoulos C, Hopkins J, Davis A. {{A Comparison of Social Cognitive Profiles in children with Autism Spectrum Disorders and Attention-Deficit/Hyperactivity Disorder: A Matter of Quantitative but not Qualitative Difference?}}. {J Autism Dev Disord};2012 (Sep 27)
The aim of this study was to compare social cognitive profiles of children and adolescents with Autism Spectrum Disorders (ASD) and ADHD. Participants diagnosed with an ASD (n = 137) were compared to participants with ADHD (n = 436) on tests of facial and vocal affect recognition, social judgment and problem-solving, and parent- and teacher-report of social functioning. Both groups performed significantly worse than the normative sample on all measures. Although the ASD group had more severe deficits, the pattern of deficits was surprisingly similar between groups, suggesting that social cognitive deficit patterns may be more similar in ASD and ADHD than previously thought. Thus, like those with ASDs, individuals with ADHD may also need to be routinely considered for treatments targeting social skills.
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3. Knoth IS, Lippe S. {{Event-related potential alterations in fragile X syndrome}}. {Front Hum Neurosci};2012;6:264.
Fragile X Syndrome (FXS) is the most common form of X-linked intellectual disability (ID), associated with a wide range of cognitive and behavioral impairments. FXS is caused by a trinucleotide repeat expansion in the FMR1 gene located on the X-chromosome. FMR1 is expected to prevent the expression of the « fragile X mental retardation protein (FMRP) », which results in altered structural and functional development of the synapse, including a loss of synaptic plasticity. This review aims to unveil the contribution of electrophysiological signal studies for the understanding of the information processing impairments in FXS patients. We discuss relevant event-related potential (ERP) studies conducted with full mutation FXS patients and clinical populations sharing symptoms with FXS in a developmental perspective. Specific deviances found in FXS ERP profiles are described. Alterations are reported in N1, P2, Mismatch Negativity (MMN), N2, and P3 components in FXS compared to healthy controls. Particularly, deviances in N1 and P2 amplitude seem to be specific to FXS. The presented results suggest a cascade of impaired information processes that are in line with symptoms and anatomical findings in FXS.
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4. Oberman LM. {{mGluR antagonists and GABA agonists as novel pharmacological agents for the treatment of autism spectrum disorders}}. {Expert Opin Investig Drugs};2012 (Sep 26)
Introduction: The CDC currently estimates the prevalence of autism spectrum disorders (ASD) at 1 in 88 children. Though the exact etiology of ASD is unknown, recent studies implicate synaptic maturation and plasticity in the pathogenesis of ASD leading to an imbalance of excitation and inhibition, and specifically a disproportionately high level of excitation. Pharmacological agents that modulate excitation and inhibition are currently in clinical trials for treatment of ASD and show promising preliminary results. Areas covered: This paper reviews the literature implicating the role of glutamate and GABA pathways in the pathophysiology of ASD. It also provides a review of the current results from both animal models and human clinical trials of drugs aimed at normalizing the imbalance of excitation and inhibition through the use of metabotropic glutamate receptor (mGluR) antagonists and GABA agonists. Expert opinion: Both mGluR antagonists and GABA agonists have promising preliminary data from animal model and small-scale Phase II human trials. They show significant efficacy in subpopulations and appear to have favorable side-effect profiles. Though preliminary data are extremely promising, results from ongoing larger, double-blind, placebo-controlled studies will give a more complete understanding of the efficacy and side-effect profile related to these drugs.
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5. Shaw TA, Porter MA. {{Emotion Recognition and Visual-Scan Paths in Fragile X Syndrome}}. {J Autism Dev Disord};2012 (Sep 27)
This study investigated emotion recognition abilities and visual scanning of emotional faces in 16 Fragile X syndrome (FXS) individuals compared to 16 chronological-age and 16 mental-age matched controls. The relationships between emotion recognition, visual scan-paths and symptoms of social anxiety, schizotypy and autism were also explored. Results indicated that, compared to both control groups, the FXS group displayed specific emotion recognition deficits for angry and neutral (but not happy or fearful) facial expressions. Despite these evident emotion recognition deficits, the visual scanning of emotional faces was found to be at developmentally appropriate levels in the FXS group. Significant relationships were also observed between visual scan-paths, emotion recognition performance and symptomology in the FXS group.
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6. Smith LE, Greenberg JS, Mailick MR. {{Adults with Autism: Outcomes, Family Effects, and the Multi-Family Group Psychoeducation Model}}. {Curr Psychiatry Rep};2012 (Sep 28)
Although an increasing number of individuals with autism spectrum disorders are entering adulthood, currently there are few evidence-based programs for individuals later in the life course. In this paper we present an overview of recent research on outcomes for adolescents and adults with ASD and highlight the role of the family for individuals with ASD during the transition to adulthood. We also discuss multi-family group psychoeducation as a promising model for use with individuals with ASD who are transitioning to adulthood.
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7. Sonie S, Kassai B, Pirat E, Bain P, Robinson J, Gomot M, Barthelemy C, Charvet D, Rochet T, Tatou M, Assouline B, Cabrol S, Chabane N, Arnaud V, Faure P, Manificat S. {{The French Version of the Autism-Spectrum Quotient in Adolescents: A Cross-Cultural Validation Study}}. {J Autism Dev Disord};2012 (Sep 27)
We assessed the accuracy of the French version of the Autism Spectrum Quotient (AQ) in adolescents with Asperger syndrome (AS) and high-functioning autism (HFA) compared to healthy controls and adolescents with psychiatric disorders (PDs). Three groups of adolescents, aged 11-18, were assessed: 116 with AS/HFA (93 with IQ >/= 85 and 20 with 70 </= IQ < 85), 39 with other PDs, and 199 healthy controls. The AS/HFA group scored significantly higher than the healthy control and PD groups. A cut-off score of 26 was used to differentiate the autism group from healthy controls with 0.89 sensitivity and 0.98 specificity. Scores did not vary by age or sex.
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8. Steinberg KM, Ramachandran D, Patel V, Shetty AC, Cutler DJ, Zwick ME. {{Identification of rare X-linked neuroligin variants by massively parallel sequencing in males with autism spectrum disorder}}. {Mol Autism};2012 (Sep 28);3(1):8.
ABSTRACT: BACKGROUND: Autism spectrum disorder (ASD) is highly heritable, but the genetic risk factors for it remain largely unknown. Although structural variants with large effect sizes may explain up to 15% ASD, genome-wide association studies have failed to uncover common single nucleotide variants with large effects on phenotype. The focus within ASD genetics is now shifting to the examination of rare sequence variants of modest effect, which is most often achieved via exome selection and sequencing. This strategy has indeed identified some rare candidate variants; however, the approach does not capture the full spectrum of genetic variation that might contribute to the phenotype. METHODS: We surveyed two loci with known rare variants that contribute to ASD, the X-linked neuroligin genes by performing massively parallel Illumina sequencing of the coding and noncoding regions from these genes in males from families with multiplex autism. We annotated all variant sites and functionally tested a subset to identify other rare mutations contributing to ASD susceptibility. RESULTS: We found seven rare variants at evolutionary conserved sites in our study population. Functional analyses of the three 3′ UTR variants did not show statistically significant effects on the expression of NLGN3 and NLGN4X. In addition, we identified two NLGN3 intronic variants located within conserved transcription factor binding sites that could potentially affect gene regulation. CONCLUSIONS: These data demonstrate the power of massively parallel, targeted sequencing studies of affected individuals for identifying rare, potentially disease-contributing variation. However, they also point out the challenges and limitations of current methods of direct functional testing of rare variants and the difficulties of identifying alleles with modest effects.
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9. Yui K. {{[Useful pharmacologic treatment in impaired social interaction in autism spectrum disorders]}}. {Seishin Shinkeigaku Zasshi};2012;114(8):934-940.
It is important to note that risperidone solution, intranasal administration of oxytocin, and dietary supplementation with large doses of arachidonic acid added to docosahexaenoic acid (DHA) have been reported to improve impaired social interaction. In addition, atypical antipsychotics aripiprazole and SSRI fluvoxamine were useful in treating some aspects of social relatedness or the core deficits of communication and socialization. The evaluation of treatments for ASD should be directed at neurobiological targets known to be important in the brain’s response to abnormal developmental trajectories or toward enhancing plasticity during the highly sensitive period in gene-environment interaction (epigenetic mechanism). Recent epidemiological studies have indicated that at least one in every 100 people has some form of ASD. Environmental chemicals can affect the development of the brain. Further studies will be required to address the effect of environmental chemicals.
