1. Colvin SM, Kwan KY. {{Dysregulated nitric oxide signaling as a candidate mechanism of fragile X syndrome and other neuropsychiatric disorders}}. {Front Genet};2014;5:239.
A mechanistic understanding of the pathophysiology underpinning psychiatric disorders is essential for the development of targeted molecular therapies. For fragile X syndrome (FXS), recent mechanistic studies have been focused on the metabotropic glutamate receptor (mGluR) signaling pathway. This line of research has led to the discovery of promising candidate drugs currently undergoing various phases of clinical trial, and represents a model of how biological insights can inform therapeutic strategies in neurodevelopmental disorders. Although mGluR signaling is a key mechanism at which targeted treatments can be directed, it is likely to be one of many mechanisms contributing to FXS. A more complete understanding of the molecular and neural underpinnings of the disorder is expected to inform additional therapeutic strategies. Alterations in the assembly of neural circuits in the neocortex have been recently implicated in genetic studies of autism and schizophrenia, and may also contribute to FXS. In this review, we explore dysregulated nitric oxide signaling in the developing neocortex as a novel candidate mechanism of FXS. This possibility stems from our previous work demonstrating that neuronal nitric oxide synthase 1 (NOS1 or nNOS) is regulated by the FXS protein FMRP in the mid-fetal human neocortex. Remarkably, in the mid-late fetal and early postnatal neocortex of human FXS patients, NOS1 expression is severely diminished. Given the role of nitric oxide in diverse neural processes, including synaptic development and plasticity, the loss of NOS1 in FXS may contribute to the etiology of the disorder. Here, we outline the genetic and neurobiological data that implicate neocortical dysfunction in FXS, review the evidence supporting dysregulated nitric oxide signaling in the developing FXS neocortex and its contribution to the disorder, and discuss the implications for targeting nitric oxide signaling in the treatment of FXS and other psychiatric illnesses.
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2. Gillespie-Smith K, Doherty-Sneddon G, Hancock PJ, Riby DM. {{That looks familiar: attention allocation to familiar and unfamiliar faces in children with autism spectrum disorder}}. {Cogn Neuropsychiatry};2014 (Aug 7):1-16.
Introduction. Existing eye-tracking literature has shown that both adults and children with autism spectrum disorders (ASD) show fewer and slower fixations on faces. Despite this reduced saliency and processing of other faces, recognition of their own face is reported to be more « typical » in nature. This study uses eye-tracking to explore the typicality of gaze patterns when children with ASD attend their own faces compared to other familiar and unfamiliar faces. Methods. Eye-tracking methodology was used to explore fixation duration and time taken to fixate on the Eye and Mouth regions of familiar, unfamiliar and Self Faces. Twenty-one children with ASD (9-16 years) were compared to typically developing matched groups. Results. There were no significant differences between children with ASD and typically matched groups for fixation patterns to the Eye and Mouth areas of all face types (familiar, unfamiliar and self). Correlational analyses showed that attention to the Eye area of unfamiliar and Self Faces was related to socio-communicative ability in children with ASD. Conclusions. Levels of socio-communicative ability in children with ASD were related to gaze patterns on unfamiliar and Self Faces, but not familiar faces. This lack of relationship between ability and attention to familiar faces may indicate that children across the autism spectrum are able to fixate these faces in a similar way. The implications for these findings are discussed.
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3. Grove R, Baillie A, Allison C, Baron-Cohen S, Hoekstra RA. {{The latent structure of cognitive and emotional empathy in individuals with autism, first-degree relatives and typical individuals}}. {Mol Autism};2014;5:42.
BACKGROUND: Empathy is a vital component for social understanding involving the ability to recognise emotion (cognitive empathy) and provide an appropriate affective response (emotional empathy). Autism spectrum conditions have been described as disorders of empathy. First-degree relatives may show some mild traits of the autism spectrum, the broader autism phenotype (BAP). Whether both cognitive and emotional empathy, rather than cognitive empathy alone, are impaired in autism and the BAP is still under debate. Moreover the association between various aspects of empathy is unclear. This study aims to examine the relationship between different components of empathy across individuals with varying levels of genetic vulnerability to autism. METHODS: Factor analyses utilising questionnaire and performance-based task data were implemented among individuals with autism, parents of a child with autism and controls. The relationship between performance-based tasks and behavioural measures of empathy was also explored. RESULTS: A four-factor model including cognitive empathy, emotional empathy, social skills and a performance-based factor fitted the data best irrespective of genetic vulnerability. Individuals with autism displayed impairment on all four factors, with parents showing intermediate difficulties. Performance-based measures of empathy were related in almost equal magnitude to cognitive and emotional empathy latent factors and the social skills factor. CONCLUSIONS: This study suggests individuals with autism have difficulties with multiple facets of empathy, while parents show intermediate impairments, providing evidence for a quantitative BAP. Impaired scores on performance-based measures of empathy, often thought to be pure measures of cognitive empathy, were also related to much wider empathy difficulties than impairments in cognitive empathy alone.
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4. Kaur K, Chauhan V, Gu F, Chauhan A. {{Bisphenol A induces oxidative stress and mitochondrial dysfunction in lymphoblasts from children with autism and unaffected siblings}}. {Free Radic Biol Med};2014 (Aug 4)
Autism is a behaviorally defined neurodevelopmental disorder. Although there is no single identifiable cause for autism, the role of genetic and environmental factors has been implicated in autism. Extensive evidence suggests increased oxidative stress and mitochondrial dysfunction in autism. In the present study, we examined whether bisphenol A (BPA) is an environmental risk factor for autism by studying its effects on oxidative stress and mitochondrial function in the lymphoblasts. When lymphoblastoid cells from autistic subjects and age-matched unaffected sibling controls were exposed to BPA, there was an increase in the generation of reactive oxygen species (ROS) and a decrease in mitochondrial membrane potential in both groups. A further sub-division of the control group into two sub groups-unaffected non-twin siblings and twin siblings- showed significantly higher ROS levels without any exposure to BPA in the unaffected twin siblings when compared to the unaffected non-twin siblings. ROS levels were also significantly higher in autism vs unaffected non-twin siblings group. The effect of BPA on three important mtDNA genes-NADH dehydrogenase 1 (ND1), NADH dehyrogenase 4 (ND4) and cytochrome B (CytB)-was analyzed to observe any changes in the mitochondria following BPA exposure. BPA induced a significant increase in the mtDNA copy number in the lymphoblasts from the unaffected siblings group, and in the unaffected twin siblings group vs unaffected non-twin siblings. In all three genes, the mtDNA increase was seen in 70% of the subjects. These results suggest that BPA exposure results in increased oxidative stress and mitochondrial dysfunction in the autistic subjects as well as age-matched sibling control subjects, particularly unaffected twin siblings. Therefore, BPA may act as an environmental risk factor for autism in genetically susceptible children by inducing oxidative stress and mitochondrial dysfunction.
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5. Kennedy DP, Adolphs R. {{Violations of personal space by individuals with autism spectrum disorder}}. {PLoS One};2014;9(8):e103369.
The ability to maintain an appropriate physical distance (i.e., interpersonal distance) from others is a critical aspect of social interaction and contributes importantly to real-life social functioning. In Study 1, using parent-report data that had been acquired on a large number of individuals (ages 4-18 years) for the Autism Genetic Resource Exchange and the Simons Simplex Collection, we found that those with Autism Spectrum Disorder (ASD; n = 766) more often violated the space of others compared to their unaffected siblings (n = 766). This abnormality held equally across ASD diagnostic categories, and correlated with clinical measures of communication and social functioning. In Study 2, laboratory experiments in a sample of high-functioning adults with ASD demonstrated an altered relationship between interpersonal distance and personal space, and documented a complete absence of personal space in 3 individuals with ASD. Furthermore, anecdotal self-report from several participants confirmed that violations of social distancing conventions continue to occur in real-world interactions through adulthood. We suggest that atypical social distancing behavior offers a practical and sensitive measure of social dysfunction in ASD, and one whose psychological and neurological substrates should be further investigated.
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6. Ko WR, Huang JY, Chiang YC, Nfor ON, Ko PC, Jan SR, Lung CC, Chang HC, Lin LY, Liaw YP. {{Risk of autistic disorder after exposure to general anaesthesia and surgery: A nationwide, retrospective matched cohort study}}. {Eur J Anaesthesiol};2014 (Aug 6)
BACKGROUND: Deficits of learning, memory and cognition have been observed in newborn animals exposed to general anaesthetics. However, conclusions from clinical studies conducted in humans to investigate the relationship between anaesthesia and neurodevelopmental disorders have been inconsistent. Autistic disorder is typically recognised earlier than other neurobehavioural disorders. Although certain genes apparently contribute to autistic disorder susceptibility, other factors such as perinatal insults and exposure to neurotoxic agents may play a crucial role in gene-environmental interaction. OBJECTIVE: This study was designed to investigate the association of exposure to general anaesthesia/surgery with autistic disorder. We hypothesised that exposure to general anaesthesia and surgery before 2 years of age is associated with an increased risk of developing autistic disorder. DESIGN: A retrospective matched-cohort study. SETTING: A medical university. Data from the National Health Insurance Research Database of Taiwan from 2001 to 2010 were analysed. PATIENTS: The birth cohort included 114 435 children, among whom 5197 were exposed to general anaesthesia and surgery before the age of 2 years. The 1 : 4 matched controls comprised 20 788 children. MAIN OUTCOME MEASURES: The primary endpoint was the diagnosis of autistic disorder after the first exposure to general anaesthesia and surgery. RESULTS: No differences were found in the incidence of autistic disorder between the exposed group (0.96%) and the unexposed controls (0.89%) (P = 0.62). Cox proportional regression showed that the hazard ratio of exposure to general anaesthesia and surgery was 0.93 [95% confidence interval (95% CI) 0.57 to 1.53] after adjusting for potential confounders. Age at first exposure did not influence the risk of autistic disorder. No relationship was found between the total number of exposures and the risk of autistic disorder. CONCLUSION: Exposure to general anaesthesia and surgery before the age of 2 years, age at first exposure and number of exposures were not associated with the development of autistic disorder.
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7. Lyall K, Constantino JN, Weisskopf MG, Roberts AL, Ascherio A, Santangelo SL. {{Parental social responsiveness and risk of autism spectrum disorder in offspring}}. {JAMA Psychiatry};2014 (Aug 1);71(8):936-942.
IMPORTANCE: Although autism spectrum disorder (ASD) is known to be heritable, patterns of inheritance of subclinical autistic traits in nonclinical samples are poorly understood. OBJECTIVE: To examine the familiality of Social Responsiveness Scale (SRS) scores of individuals with and without ASD. DESIGN, SETTING, AND PARTICIPANTS: We performed a nested case-control study (pilot study: July 1, 2007, through June 30, 2009; full-scale study: September 15, 2008, through September 14, 2012) within a population-based longitudinal cohort. Participants were drawn from the Nurses’ Health Study II, a cohort of 116 430 female nurses recruited in 1989. Case participants were index children with reported ASD; control participants were frequency matched by year of birth of case participants among those not reporting ASD. Of 3161 eligible participants, 2144 nurses (67.8%) returned SRS forms for a child and at least 1 parent and were included in these analyses. EXPOSURE: The SRS scores, as reported by nurse mothers and their spouses, were examined in association with risk of ASD using crude and adjusted logistic regression analyses. The SRS scores of the children were examined in association with SRS scores of the parents using crude and adjusted linear regression analyses stratified by case status. MAIN OUTCOMES AND MEASURES: Autism spectrum disorder, assessed by maternal report, validated in a subgroup with the Autism Diagnostic Interview-Revised. RESULTS: A total of 1649 individuals were included in these analyses, including 256 ASD case participants, 1393 control participants, 1233 mothers, and 1614 fathers. Risk of ASD was increased by 85.0% among children whose parents had concordantly elevated SRS scores (odds ratio [OR], 1.85; 95% CI, 1.08-3.16) and by 52.0% when the score of either parent was elevated (OR, 1.52; 95% CI, 1.11-2.06). Elevated scores of the father significantly increased the risk of ASD in the child (OR, 1.94; 95% CI, 1.38-2.71), but no association was seen with elevated scores of the mother. Elevated parent scores significantly increased child scores in controls, corresponding to an increase in 23 points (P < .001). CONCLUSIONS AND RELEVANCE: These findings support the role of additive genetic influences in concentrating inherited ASD susceptibility in successive generations and the potential role of preferential mating, and suggest that typical variation in parental social functioning can produce clinically significant differences in offspring social traits.
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8. Moscato F, Solano P. {{Eating Disorders as Autisticlike Defenses: Unmentalizable Experiences in Primitive Mental States}}. {Psychoanal Rev};2014 (Aug);101(4):547-570.
Autisticlike symptoms have been acknowledged in several fields; thus it cannot be claimed that they encompass a delineated pathological organization. The authors argue that in primitive mental functioning, eating symptoms-both bulimic and anorexic-can be used as autisticlike defenses in which the altered body becomes an objectified protective shell providing shelter from intolerable anxieties that derive from unmentalized and unmentalizable experiences. The role of the psychoanalytic third, rising from the analyst’s reverie, as a possible meeting ground between the concrete and the symbolic is discussed. Drawing on case material from the analysis of two patients with eating symptoms used as autisticlike defenses clarifies some of the theoretical aspects of eating disorders.
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9. Noordhof A, Krueger RF, Ormel J, Oldehinkel AJ, Hartman CA. {{Integrating Autism-Related Symptoms into the Dimensional Internalizing and Externalizing Model of Psychopathology. The TRAILS Study}}. {J Abnorm Child Psychol};2014 (Aug 8)
Problems associated with Autism Spectrum Disorder (ASD) occur frequently in the general population and often co-occur with problems in other domains of psychopathology. In the research presented here these co-occurrence patterns were investigated by integrating a dimensional approach to ASDs into the more general dimensional framework of internalizing and externalizing psychopathology. Factor Analysis was used to develop hierarchical and bi-factor models covering multiple domains of psychopathology in three measurement waves of a longitudinal general population sample (N = 2,230, ages 10-17, 50.8 % female). In all adequately fitting models, autism related problems were part of a specific domain of psychopathology that could be distinguished from the internalizing and externalizing domains. Optimal model fit was found for a bi-factor model with one non-specific factor and four specific factors related to internalizing, externalizing, autism spectrum problems and problems related to attention and orientation. Autism-related problems constitute a specific domain of psychopathology that can be distinguished from the internalizing and externalizing domains. In addition, the co-occurrence patterns in the data indicate the presence of a strong general factor.
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10. Poulin-Lord MP, Barbeau EB, Soulieres I, Monchi O, Doyon J, Benali H, Mottron L. {{Increased topographical variability of task-related activation in perceptive and motor associative regions in adult autistics}}. {Neuroimage Clin};2014;4:444-453.
BACKGROUND: An enhanced plasticity is suspected to play a role in various microstructural alterations, as well as in regional cortical reallocations observed in autism. Combined with multiple indications of enhanced perceptual functioning in autism, and indications of atypical motor functioning, enhanced plasticity predicts a superior variability in functional cortical allocation, predominant in perceptual and motor regions. METHOD: To test this prediction, we scanned 23 autistics and 22 typical participants matched on age, FSIQ, Raven percentile scores and handedness during a visuo-motor imitation task. For each participant, the coordinates of the strongest task-related activation peak were extracted in the primary (Brodmann area 4) and supplementary (BA 6) motor cortex, the visuomotor superior parietal cortex (BA 7), and the primary (BA 17) and associative (BAs 18 + 19) visual areas. Mean signal changes for each ROI in both hemispheres, and the number of voxels composing the strongest activation cluster were individually extracted to compare intensity and size of the signal between groups. For each ROI, in each hemisphere, and for every participant, the distance from their respective group average was used as a variable of interest to determine group differences in localization variability using repeated measures ANOVAs. Between-group comparison of whole-brain activation was also performed. RESULTS: Both groups displayed a higher mean variability in the localization of activations in the associative areas compared to the primary visual or motor areas. However, despite this shared increased variability in associative cortices, a direct between-group comparison of the individual variability in localization of the activation revealed a significantly greater variability in the autistic group than in the typical group in the left visuo-motor superior parietal cortex (BA 7) and in the left associative visual areas (BAs 18 + 19). CONCLUSION: Different and possibly unique strategies are used by each autistic individual. That enhanced variability in localization of activations in the autistic group is found in regions typically more variable in non-autistics raises the possibility that autism involves an enhancement and/or an alteration of typical plasticity mechanisms. The current study also highlights the necessity to verify, in fMRI studies involving autistic people, that hypoactivation at the group level does not result from each individual successfully completing a task using a unique brain allocation, even by comparison to his own group.
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11. Rahbar MH, Samms-Vaughan M, Ma J, Bressler J, Loveland KA, Ardjomand-Hessabi M, Dickerson AS, Grove ML, Shakespeare-Pellington S, Beecher C, McLaughlin W, Boerwinkle E. {{Role of Metabolic Genes in Blood Arsenic Concentrations of Jamaican Children with and without Autism Spectrum Disorder}}. {Int J Environ Res Public Health};2014;11(8):7874-7895.
Arsenic is a toxic metalloid with known adverse effects on human health. Glutathione-S-transferase (GST) genes, including GSTT1, GSTP1, and GSTM1, play a major role in detoxification and metabolism of xenobiotics. We investigated the association between GST genotypes and whole blood arsenic concentrations (BASC) in Jamaican children with and without autism spectrum disorder (ASD). We used data from 100 ASD cases and their 1:1 age- and sex-matched typically developing (TD) controls (age 2-8 years) from Jamaica. Using log-transformed BASC as the dependent variable in a General Linear Model, we observed a significant interaction between GSTP1 and ASD case status while controlling for several confounding variables. However, for GSTT1 and GSTM1 we did not observe any significant associations with BASC. Our findings indicate that TD children who had the Ile/Ile or Ile/Val genotype for GSTP1 had a significantly higher geometric mean BASC than those with genotype Val/Val (3.67 microg/L vs. 2.69 microg/L, p < 0.01). Although, among the ASD cases, this difference was not statistically significant, the direction of the observed difference was consistent with that of the TD control children. These findings suggest a possible role of GSTP1 in the detoxification of arsenic.
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12. Saitsu H, Tohyama J, Walsh T, Kato M, Kobayashi Y, Lee M, Tsurusaki Y, Miyake N, Goto YI, Nishino I, Ohtake A, King MC, Matsumoto N. {{A girl with West syndrome and autistic features harboring a de novo TBL1XR1 mutation}}. {J Hum Genet};2014 (Aug 7)
Recently, de novo mutations in TBL1XR1 were found in two patients with autism spectrum disorders. Here, we report on a Japanese girl presenting with West syndrome, Rett syndrome-like and autistic features. Her initial development was normal until she developed a series of spasms at 5 months of age. Electroencephalogram at 7 months showed a pattern of hypsarrhythmia, which led to a diagnosis of West syndrome. Stereotypic hand movements appeared at 8 months of age, and autistic features such as deficits in communication, hyperactivity and excitability were observed later, at 4 years and 9 months. Whole exome sequencing of the patient and her parents revealed a de novo TBL1XR1 mutation [c.209 G>A (p.Gly70Asp)] occurring at an evolutionarily conserved amino acid in an F-box-like domain. Our report expands the clinical spectrum of TBL1XR1 mutations to West syndrome with Rett-like features, together with autistic features.Journal of Human Genetics advance online publication, 7 August 2014; doi:10.1038/jhg.2014.71.
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13. Shohat S, Shifman S. {{Bias towards large genes in autism}}. {Nature};2014 (Aug 7);512(7512):E1-2.
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14. Ten Eycke KD, Muller U. {{Brief Report: New Evidence for a Social-Specific Imagination Deficit in Children with Autism Spectrum Disorder}}. {J Autism Dev Disord};2014 (Aug 8)
Previous research suggests that children with autism have deficits in drawing imaginative content. However, these conclusions are largely based on tasks that require children to draw impossible persons, and performance on this task may be limited by social deficits. To determine the generality of the deficit in imagination in children with autism, we asked 25 children with autism (mean age 9;7) and 29 neurotypically developing children (mean age 8;7) to draw an imaginative person and house. Drawings of imaginary houses by children with autism did not differ from those by neurotypically developing controls, but drawings of persons were significantly less imaginative. These findings suggest that the impairment in imagination among children with autism may be specific to social stimuli.
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15. Uppal N, Wicinski B, Buxbaum JD, Heinsen H, Schmitz C, Hof PR. {{Neuropathology of the Anterior Midcingulate Cortex in Young Children With Autism}}. {J Neuropathol Exp Neurol};2014 (Aug 6)
The anterior cingulate cortex, which is involved in cognitive and affective functioning, is important in investigating disorders in which individuals exhibit impairments in higher-order functions. In this study, we examined the anterior midcingulate cortex (aMCC) at the cellular level in patients with autism and in controls. We focused our analysis on layer V of the aMCC because it contains von Economo neurons, specialized cells thought to be involved in emotional expression and focused attention. Using a stereologic approach, we determined whether there were neuropathologic changes in von Economo neuron number, pyramidal neuron number, or pyramidal neuron size between diagnostic groups. When the groups were subdivided into young children and adolescents, pyramidal neuron and von Economo neuron numbers positively correlated with autism severity in young children, as measured by the Autism Diagnostic Interview-Revised. Young children with autism also had significantly smaller pyramidal neurons than their matched controls. Because the aMCC is involved in decision-making during uncertain situations, decreased pyramidal neuron size may reflect a potential reduction in the functional connectivity of the aMCC.
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16. Usdin K, Hayward BE, Kumari D, Lokanga RA, Sciascia N, Zhao XN. {{Repeat-mediated genetic and epigenetic changes at the FMR1 locus in the Fragile X-related disorders}}. {Front Genet};2014;5:226.
The Fragile X-related disorders are a group of genetic conditions that include the neurodegenerative disorder, Fragile X-associated tremor/ataxia syndrome (FXTAS), the fertility disorder, Fragile X-associated primary ovarian insufficiency (FXPOI) and the intellectual disability, Fragile X syndrome (FXS). The pathology in all these diseases is related to the number of CGG/CCG-repeats in the 5′ UTR of the Fragile X mental retardation 1 (FMR1) gene. The repeats are prone to continuous expansion and the increase in repeat number has paradoxical effects on gene expression increasing transcription on mid-sized alleles and decreasing it on longer ones. In some cases the repeats can simultaneously both increase FMR1 mRNA production and decrease the levels of the FMR1 gene product, Fragile X mental retardation 1 protein (FMRP). Since FXTAS and FXPOI result from the deleterious consequences of the expression of elevated levels of FMR1 mRNA and FXS is caused by an FMRP deficiency, the clinical picture is turning out to be more complex than once appreciated. Added complications result from the fact that increasing repeat numbers make the alleles somatically unstable. Thus many individuals have a complex mixture of different sized alleles in different cells. Furthermore, it has become apparent that the eponymous fragile site, once thought to be no more than a useful diagnostic criterion, may have clinical consequences for females who inherit chromosomes that express this site. This review will cover what is currently known about the mechanisms responsible for repeat instability, for the repeat-mediated epigenetic changes that affect expression of the FMR1 gene, and for chromosome fragility. It will also touch on what current and future options are for ameliorating some of these effects.
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17. Wada M, Suzuki M, Takaki A, Miyao M, Spence C, Kansaku K. {{Spatio-temporal processing of tactile stimuli in autistic children}}. {Sci Rep};2014;4:5985.
Altered multisensory integration has been reported in autism; however, little is known concerning how the autistic brain processes spatio-temporal information concerning tactile stimuli. We report a study in which a crossed-hands illusion was investigated in autistic children. Neurotypical individuals often experience a subjective reversal of temporal order judgments when their hands are stimulated while crossed, and the illusion is known to be acquired in early childhood. However, under those conditions where the somatotopic representation is given priority over the actual spatial location of the hands, such reversals may not occur. Here, we showed that a significantly smaller illusory reversal was demonstrated in autistic children than in neurotypical children. Furthermore, in an additional experiment, the young boys who had higher Autism Spectrum Quotient (AQ) scores generally showed a smaller crossed hands deficit. These results suggest that rudimentary spatio-temporal processing of tactile stimuli exists in autistic children, and the altered processing may interfere with the development of an external frame of reference in real-life situations.
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18. Wang SS, Kloth AD, Badura A. {{The Cerebellum, Sensitive Periods, and Autism}}. {Neuron};2014 (Aug 6);83(3):518-532.
Cerebellar research has focused principally on adult motor function. However, the cerebellum also maintains abundant connections with nonmotor brain regions throughout postnatal life. Here we review evidence that the cerebellum may guide the maturation of remote nonmotor neural circuitry and influence cognitive development, with a focus on its relationship with autism. Specific cerebellar zones influence neocortical substrates for social interaction, and we propose that sensitive-period disruption of such internal brain communication can account for autism’s key features.
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19. Williams DL, Mazefsky CA, Walker JD, Minshew NJ, Goldstein G. {{Associations Between Conceptual Reasoning, Problem Solving, and Adaptive Ability in High-functioning Autism}}. {J Autism Dev Disord};2014 (Aug 7)
Abstract thinking is generally highly correlated with problem-solving ability which is predictive of better adaptive functioning. Measures of conceptual reasoning, an ecologically-valid laboratory measure of problem-solving, and a report measure of adaptive functioning in the natural environment, were administered to children and adults with and without autism. The individuals with autism had weaker conceptual reasoning ability than individuals with typical development of similar age and cognitive ability. For the autism group, their flexible thinking scores were significantly correlated with laboratory measures of strategy formation and rule shifting and with reported overall adaptive behavior but not socialization scores. Therefore, in autism, flexibility of thought is potentially more important for adaptive functioning in the natural environment than conceptual reasoning or problem-solving.
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20. Yang JC, Chi L, Teichholtz S, Schneider A, Nanakul R, Nowacki R, Seritan A, Reed B, DeCarli C, Iragui VJ, Kutas M, Hagerman PJ, Hagerman RJ, Olichney JM. {{ERP Abnormalities elicited by word repetition in fragile X-associated tremor/ataxia syndrome (FXTAS) and amnestic MCI}}. {Neuropsychologia};2014 (Aug 8)
BACKGROUND: Fragile X-associated tremor/ataxia syndrome (FXTAS), a neurodegenerative disorder caused by FMR1 gene premutations, typically associated with frontal-subcortical type cognitive impairments. High prevalence (~50%) of superimposed Alzheimer’s pathology has been reported in FMR1 premutation carriers, and standardized neuropsychological tests have not yielded any robust discriminators between FXTAS and Alzheimer’s disease (AD) dementia. The similarities/differences in memory processes between FXTAS and early AD remain underexplored. METHODS: 32-channel event-related potentials (ERPs) were obtained from a semantic judgment task in which semantically congruous (50%) and incongruous pairs repeat pseudorandomly. The N400 and late positive component (LPC) of 25 FXTAS patients (Mage=71.2, MMSE=26.6) were compared to a matched group of 25 patients with MCI or early AD (1 mild AD dementia, 24 amnestic MCI, of whom 18 later converted to AD; Mage=73.4, MMSE=26.4), and 25 healthy elderly. RESULTS: Both patient groups showed similar reductions in the N400 repetition effect and N400 congruity effect amplitudes, compared to controls, reflecting abnormal semantic priming and repetition priming. The MCI/AD group, however, had significantly smaller LPC word repetition effects and poorer learning and memory on the CVLT than FXTAS. The LPC and N400 repetition effects both correlated with verbal memory across all subjects, but only the N400 correlated with memory in FXTAS. CONCLUSION: FXTAS patients show relative sparing of the LPC repetition effect, and less disruption of explicit memory than prodromal/early AD. N400 abnormalities in FXTAS appear to account for much of their mild impairments in verbal learning and memory.
