1. Ashwin C, Hietanen JK, Baron-Cohen S. {{Atypical integration of social cues for orienting to gaze direction in adults with autism}}. {Mol Autism}. 2015; 6(1): 5.
BACKGROUND: Gaze direction provides important information about social attention, and people tend to reflexively orient in the direction others are gazing. Perceiving the gaze of others relies on the integration of multiple social cues, which include perceptual information related to the eyes, gaze direction, head position, and body orientation of others. Autism spectrum conditions (ASC) are characterised by social and emotional deficits, including atypical gaze behaviour. The social-emotional deficits may emerge from a reliance on perceptual information involving details and features, at the expense of more holistic processing, which includes the integration of features. While people with ASC are often able to physically compute gaze direction and show intact reflexive orienting to others’ gaze, they show deficits in reading mental states from the eyes. METHODS: The present study recruited 23 adult males with a diagnosis of ASC and 23 adult males without ASC as a control group. They were tested using a spatial cuing paradigm involving head and body cues in a photograph of a person followed by a laterally presented target. The task manipulated the orientation of head with respect to body orientation to test subsequent shifts of attention in observers. RESULTS: The results replicated previous findings showing facilitated shifts of attention by the healthy control participants toward laterally presented targets cued by a congruently rotated head combined with a front view of a body. In contrast, the ASC group showed facilitated orienting to targets when both the head and body were rotated towards the target. CONCLUSIONS: The findings reveal atypical integration of social cues in ASC for orienting of attention. This is suggested to reflect abnormalities in cognitive and neural mechanisms specialized for processing of social cues for attention orienting in ASC.
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2. Brook E, Usman M. {{SSRIs in Rett syndrome}}. {Aust N Z J Psychiatry}. 2015.
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3. Chen E, Joseph S. {{Fragile X mental retardation protein: A paradigm for translational control by RNA-binding proteins}}. {Biochimie}. 2015.
Translational control is a common mechanism used to regulate gene expression and occur in bacteria to mammals. Typically in translational control, an RNA-binding protein binds to a unique sequence in the mRNA to regulate protein synthesis by the ribosomes. Alternatively, a protein may bind to or modify a translation factor to globally regulate protein synthesis by the cell. Here, we review translational control by the fragile X mental retardation protein (FMRP), the absence of which causes the neurological disease, fragile X syndrome (FXS).
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4. Eye PG, Hawley JS. {{Pearls & Oy-sters: Fragile X tremor/ataxia syndrome: A diagnostic dilemma}}. {Neurology}. 2015; 84(7): e43-5.
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5. Hidding E, Swaab H, Vorstman JA, van Engeland H, Sijmens-Morcus ME, Klaassen PW, Duijff SN, de Sonneville LM. {{Intellectual functioning in relation to autism and ADHD symptomatology in children and adolescents with 22q11.2 deletion syndrome}}. {J Intellect Disabil Res}. 2015.
BACKGROUND: The 22q11.2 deletion syndrome (22q11DS; velo-cardio-facial syndrome) is associated with an increased risk of various disorders, including autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD). With this study, we aimed to investigate the relation between intellectual functioning and severity of ASD and ADHD symptomatology in 22q11DS. METHOD: A sample of 102 individuals (62 females) with 22q11DS aged 9 to 18.5 years were assessed using age appropriate Wechsler scales of intelligence as well as psychological and psychiatric assessment to evaluate the presence of ASD and ADHD symptomatology. RESULTS: Intelligence profiles were characterised by lower scores on the factor perceptual organisation and higher scores on the factor processing speed, with on subtest level higher scores on digit span and lower scores on arithmetic and vocabulary as compared with the mean factor or subtest score respectively. No differences in intelligence profiles were found between subgroups with and without ASD and/or ADHD. Low scores on coding were associated with higher severity of ASD symptomatology, while lower scores on block design were associated with more severe ADHD symptomatology. CONCLUSIONS: On several sub-domains of intelligence, poorer performance was associated with higher severity of ASD and ADHD symptomatology. The impact of developmental disorders in 22q11DS can be traced in specific domains of intellectual functioning as well as in severity of symptomatology.
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6. Lim CM. {{Accommodating Autistics and Treating Autism: Can We Have Both?}}. {Bioethics}. 2015.
One of the central claims of the neurodiversity movement is that society should accommodate the needs of autistics, rather than try to treat autism. People have variously tried to reject this accommodation thesis as applicable to all autistics. One instance is Pier Jaarsma and Stellan Welin, who argue that the thesis should apply to some but not all autistics. They do so via separating autistics into high- and low-functioning, on the basis of IQ and social effectiveness or functionings. I reject their grounds for separating autistics. IQ is an irrelevant basis for separating autistics. Charitably rendering it as referring to more general capacities still leaves us mistaken about the roles they play in supporting the accommodation thesis. The appeal to social effectiveness or functionings relies on standards that are inapplicable to autistics, and which risks being deaf to the point of their claims. I then consider if their remaining argument concerning autistic culture may succeed independently of the line they draw. I argue that construing autistics’ claims as beginning from culture mistakes their status, and may even detract from their aims. Via my discussion of Jaarsma and Welin, I hope to point to why the more general strategy of separating autistics, in response to the accommodation thesis, does not fully succeed. Finally, I sketch some directions for future discussions, arguing that we should instead shift our attention to consider another set of questions concerning the costs and extent of change required to accommodate all autistics.
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7. Miller SA, Rodriguez NM, Rourke AJ. {{Do mirrors facilitate acquisition of motor imitation in children diagnosed with autism?}}. {J Appl Behav Anal}. 2015.
We evaluated the efficacy of a procedure that incorporated a mirror to teach gross motor imitation with a 2-year-old boy who had been diagnosed with autistic disorder. Responses taught with a mirror were acquired more quickly than responses taught without the mirror and were maintained after the mirror was removed. These data indicate that a mirror can facilitate acquisition of motor imitation.
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8. Morin K, Guy J, Habak C, Wilson HR, Pagani L, Mottron L, Bertone A. {{Atypical Face Perception in Autism: A Point of View?}}. {Autism Res}. 2015.
Face perception is the most commonly used visual metric of social perception in autism. However, when found to be atypical, the origin of face perception differences in autism is contentious. One hypothesis proposes that a locally oriented visual analysis, characteristic of individuals with autism, ultimately affects performance on face tasks where a global analysis is optimal. The objective of this study was to evaluate this hypothesis by assessing face identity discrimination with synthetic faces presented with and without changes in viewpoint, with the former condition minimizing access to local face attributes used for identity discrimination. Twenty-eight individuals with autism and 30 neurotypical participants performed a face identity discrimination task. Stimuli were synthetic faces extracted from traditional face photographs in both front and 20 degrees side viewpoints, digitized from 37 points to provide a continuous measure of facial geometry. Face identity discrimination thresholds were obtained using a two-alternative, temporal forced choice match-to-sample paradigm. Analyses revealed an interaction between group and condition, with group differences found only for the viewpoint change condition, where performance in the autism group was decreased compared to that of neurotypical participants. The selective decrease in performance for the viewpoint change condition suggests that face identity discrimination in autism is more difficult when access to local cues is minimized, and/or when dependence on integrative analysis is increased. These results lend support to a perceptual contribution of atypical face perception in autism. Autism Res 2015. (c) 2015 International Society for Autism Research, Wiley Periodicals, Inc.
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9. Okray Z, de Esch CE, Van Esch H, Devriendt K, Claeys A, Yan J, Verbeeck J, Froyen G, Willemsen R, de Vrij FM, Hassan BA. {{A novel fragile X syndrome mutation reveals a conserved role for the carboxy-terminus in FMRP localization and function}}. {EMBO Mol Med}. 2015.
Loss of function of the FMR1 gene leads to fragile X syndrome (FXS), the most common form of intellectual disability. The loss of FMR1 function is usually caused by epigenetic silencing of the FMR1 promoter leading to expansion and subsequent methylation of a CGG repeat in the 5′ untranslated region. Very few coding sequence variations have been experimentally characterized and shown to be causal to the disease. Here, we describe a novel FMR1 mutation and reveal an unexpected nuclear export function for the C-terminus of FMRP. We screened a cohort of patients with typical FXS symptoms who tested negative for CGG repeat expansion in the FMR1 locus. In one patient, we identified a guanine insertion in FMR1 exon 15. This mutation alters the open reading frame creating a short novel C-terminal sequence, followed by a stop codon. We find that this novel peptide encodes a functional nuclear localization signal (NLS) targeting the patient FMRP to the nucleolus in human cells. We also reveal an evolutionarily conserved nuclear export function associated with the endogenous C-terminus of FMRP. In vivo analyses in Drosophila demonstrate that a patient-mimetic mutation alters the localization and function of Dfmrp in neurons, leading to neomorphic neuronal phenotypes.
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10. Ouellette-Kuntz H, Coo H, Cobigo V, Wilton AS. {{Uptake of Colorectal Cancer Screening among Ontarians with Intellectual and Developmental Disabilities}}. {PLoS One}. 2015; 10(2): e0118023.
Under-screening for cancer may contribute to a greater disease burden in individuals with intellectual and developmental disabilities (IDD) as their life expectancy increases. In 2008, the province of Ontario launched Canada’s first population-based colorectal cancer screening program. Our objectives were to compare the proportions of Ontarians with and without IDD who have undergone colorectal cancer screening and to examine factors associated with screening uptake among Ontarians with IDD. Records for Ontario residents 50-64 years of age were linked across various administrative health and social services datasets to identify individuals with IDD and to select a random sample of the age-equivalent Ontario population without IDD as a comparison group. Logistic regression models were fit to examine the odds of screening uptake among individuals with IDD while controlling for age, sex, urban or rural residence, neighbourhood income quintile, expected use of health care resources, and being enrolled with or seeing a physician in a patient enrolment model (any of several primary care practice models designed to improve patient access and quality of care in Ontario), and to examine the association between these variables and colorectal cancer screening in the IDD population. The odds of having had a fecal occult blood test in the previous two years and being up-to-date with colorectal tests were 32% and 46% lower, respectively, for Ontarians with IDD compared to those without IDD. Being older, female, having a greater expected use of health care resources, and being enrolled with or seeing a physician in a primary care patient enrolment model were all significantly associated with higher odds of having been screened for colorectal cancer in the IDD population. These findings underscore the need for targeted interventions aimed at making colorectal cancer screening more equitable.
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11. Plitt M, Barnes KA, Martin A. {{Functional connectivity classification of autism identifies highly predictive brain features but falls short of biomarker standards}}. {Neuroimage Clin}. 2015; 7: 359-66.
OBJECTIVES: Autism spectrum disorders (ASD) are diagnosed based on early-manifesting clinical symptoms, including markedly impaired social communication. We assessed the viability of resting-state functional MRI (rs-fMRI) connectivity measures as diagnostic biomarkers for ASD and investigated which connectivity features are predictive of a diagnosis. METHODS: Rs-fMRI scans from 59 high functioning males with ASD and 59 age- and IQ-matched typically developing (TD) males were used to build a series of machine learning classifiers. Classification features were obtained using 3 sets of brain regions. Another set of classifiers was built from participants’ scores on behavioral metrics. An additional age and IQ-matched cohort of 178 individuals (89 ASD; 89 TD) from the Autism Brain Imaging Data Exchange (ABIDE) open-access dataset (http://fcon_1000.projects.nitrc.org/indi/abide/) were included for replication. RESULTS: High classification accuracy was achieved through several rs-fMRI methods (peak accuracy 76.67%). However, classification via behavioral measures consistently surpassed rs-fMRI classifiers (peak accuracy 95.19%). The class probability estimates, P(ASD|fMRI data), from brain-based classifiers significantly correlated with scores on a measure of social functioning, the Social Responsiveness Scale (SRS), as did the most informative features from 2 of the 3 sets of brain-based features. The most informative connections predominantly originated from regions strongly associated with social functioning. CONCLUSIONS: While individuals can be classified as having ASD with statistically significant accuracy from their rs-fMRI scans alone, this method falls short of biomarker standards. Classification methods provided further evidence that ASD functional connectivity is characterized by dysfunction of large-scale functional networks, particularly those involved in social information processing.
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12. Rahbar MH, Samms-Vaughan M, Ma J, Bressler J, Loveland KA, Hessabi M, Dickerson AS, Grove ML, Shakespeare-Pellington S, Beecher C, McLaughlin W, Boerwinkle E. {{Interaction between and allele variants as a risk modulating-factor for autism spectrum disorders}}. {Res Autism Spectr Disord}. 2015; 12: 1-9.
We investigated the role of glutathione S-transferase (GST) genes in Autism Spectrum Disorder (ASD). We used data from 111 pairs of age- and sex-matched ASD cases and typically developing (TD) controls between 2-8 years of age from Jamaica to investigate the role of GST pi 1 (GSTP1), GST theta 1 (GSTT1), and GST mu 1 (GSTM1) polymorphisms in susceptibility to ASD. In univariable conditional logistic regression models we did not observe significant associations between ASD status and GSTT1, GSTM1, or GSTP1 genotype (all P > 0.15). However, in multivariable conditional logistic regression models, we identified a significant interaction between GSTP1 and GSTT1 in relation to ASD. Specifically, in children heterozygous for the GSTP1 Ile105Val polymorphism, the odds of ASD was significantly higher in those with the null GSTT1 genotype than those with the other genotypes [Matched Odds Ratio (MOR) = 2.97, 95% CI (1.09, 8.01), P = 0.03]. Replication in other populations is warranted.
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13. Russo-Ponsaran NM, McKown C, Johnson JK, Allen AW, Evans-Smith B, Fogg L. {{Social-Emotional Correlates of Early Stage Social Information Processing Skills in Children With and Without Autism Spectrum Disorder}}. {Autism Res}. 2015.
Difficulty processing social information is a defining feature of autism spectrum disorder (ASD). Yet the failure of children with ASD to process social information effectively is poorly understood. Using Crick and Dodge’s model of social information processing (SIP), this study examined the relationship between social-emotional (SE) skills of pragmatic language, theory of mind, and emotion recognition on the one hand, and early stage SIP skills of problem identification and goal generation on the other. The study included a sample of school-aged children with and without ASD. SIP was assessed using hypothetical social situations in the context of a semistructured scenario-based interview. Pragmatic language, theory of mind, and emotion recognition were measured using direct assessments. Social thinking differences between children with and without ASD are largely differences of quantity (overall lower performance in ASD), not discrepancies in cognitive processing patterns. These data support theoretical models of the relationship between SE skills and SIP. Findings have implications for understanding the mechanisms giving rise to SIP deficits in ASD and may ultimately inform treatment development for children with ASD. Autism Res 2015. (c) 2015 International Society for Autism Research, Wiley Periodicals, Inc.
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14. Whipple CM, Gfeller K, Driscoll V, Oleson J, McGregor K. {{Do Communication Disorders Extend to Musical Messages? An Answer from Children with Hearing Loss or Autism Spectrum Disorders}}. {J Music Ther}. 2015.
BACKGROUND: Effective musical communication requires conveyance of the intended message in a manner perceptible to the receiver. Communication disorders that impair transmitting or decoding of structural features of music (e.g., pitch, timbre) and/or symbolic representation may result in atypical musical communication, which can have a negative impact on music therapy interventions. OBJECTIVE: This study compared recognition of symbolic representation of emotions or movements in music by two groups of children with different communicative characteristics: severe to profound hearing loss (using cochlear implants [CI]) and autism spectrum disorder (ASD). Their responses were compared to those of children with typical-development and normal hearing (TD-NH). Accuracy was examined as a function of communicative status, emotional or movement category, and individual characteristics. METHODS: Participants listened to recorded musical excerpts conveying emotions or movements and matched them with labels. Measures relevant to auditory and/or language function were also gathered. RESULTS: There was no significant difference between the ASD and TD-NH groups in identification of musical emotions or movements. However, the CI group was significantly less accurate than the other two groups in identification of both emotions and movements. Mixed effects logistic regression revealed different patterns of accuracy for specific emotions as a function of group. CONCLUSION: Conveyance of emotions or movements through music may be decoded differently by persons with different types of communication disorders. Because music is the primary therapeutic tool in music therapy sessions, clinicians should consider these differential abilities when selecting music for clinical interventions focusing on emotions or movement.
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15. Zurcher NR, Bhanot A, McDougle CJ, Hooker JM. {{A systematic review of molecular imaging (PET and SPECT) in autism spectrum disorder: Current state and future research opportunities}}. {Neurosci Biobehav Rev}. 2015.
Non-invasive positron emission tomography (PET) and single-photon emission computed tomography (SPECT) are techniques used to quantify molecular interactions, biological processes and protein concentration and distribution. In the central nervous system, these molecular imaging techniques can provide critical insights into neurotransmitter receptors and their occupancy by neurotransmitters or drugs. In recent years, there has been an increase in the number of studies that have investigated neurotransmitters in autism spectrum disorders (ASDs), while earlier studies mostly focused on cerebral blood flow and glucose metabolism. The underlying and contributing mechanisms of ASD are largely undetermined and ASD diagnosis relies on the behavioral phenotype. Discovery of biochemical endophenotypes would represent a milestone in autism research that could potentially lead to ASD subtype stratification and the development of novel therapeutic drugs. This review characterizes the prior use of molecular imaging by PET and SPECT in ASD, addresses methodological challenges and highlights areas of future opportunity for contributions from molecular imaging to understand ASD pathophysiology.
