865 resultados para high-functioning autism spectrum disorder


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Background Atypical self-processing is an emerging theme in autism research, suggested by lower self-reference effect in memory, and atypical neural responses to visual self-representations. Most research on physical self-processing in autism uses visual stimuli. However, the self is a multimodal construct, and therefore, it is essential to test self-recognition in other sensory modalities as well. Self-recognition in the auditory modality remains relatively unexplored and has not been tested in relation to autism and related traits. This study investigates self-recognition in auditory and visual domain in the general population and tests if it is associated with autistic traits. Methods Thirty-nine neurotypical adults participated in a two-part study. In the first session, individual participant’s voice was recorded and face was photographed and morphed respectively with voices and faces from unfamiliar identities. In the second session, participants performed a ‘self-identification’ task, classifying each morph as ‘self’ voice (or face) or an ‘other’ voice (or face). All participants also completed the Autism Spectrum Quotient (AQ). For each sensory modality, slope of the self-recognition curve was used as individual self-recognition metric. These two self-recognition metrics were tested for association between each other, and with autistic traits. Results Fifty percent ‘self’ response was reached for a higher percentage of self in the auditory domain compared to the visual domain (t = 3.142; P < 0.01). No significant correlation was noted between self-recognition bias across sensory modalities (τ = −0.165, P = 0.204). Higher recognition bias for self-voice was observed in individuals higher in autistic traits (τ AQ = 0.301, P = 0.008). No such correlation was observed between recognition bias for self-face and autistic traits (τ AQ = −0.020, P = 0.438). Conclusions Our data shows that recognition bias for physical self-representation is not related across sensory modalities. Further, individuals with higher autistic traits were better able to discriminate self from other voices, but this relation was not observed with self-face. A narrow self-other overlap in the auditory domain seen in individuals with high autistic traits could arise due to enhanced perceptual processing of auditory stimuli often observed in individuals with autism.

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Joint attention (JA) and spontaneous facial mimicry (SFM) are fundamental processes in social interactions, and they are closely related to empathic abilities. When tested independently, both of these processes have been usually observed to be atypical in individuals with autism spectrum conditions (ASC). However, it is not known how these processes interact with each other in relation to autistic traits. This study addresses this question by testing the impact of JA on SFM of happy faces using a truly interactive paradigm. Sixty-two neurotypical participants engaged in gaze-based social interaction with an anthropomorphic, gaze-contingent virtual agent. The agent either established JA by initiating eye contact or looked away, before looking at an object and expressing happiness or disgust. Eye tracking was used to make the agent's gaze behavior and facial actions contingent to the participants' gaze. SFM of happy expressions was measured by Electromyography (EMG) recording over the Zygomaticus Major muscle. Results showed that JA augments SFM in individuals with low compared with high autistic traits. These findings are in line with reports of reduced impact of JA on action imitation in individuals with ASC. Moreover, they suggest that investigating atypical interactions between empathic processes, instead of testing these processes individually, might be crucial to understanding the nature of social deficits in autism

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In humans, both language and fine motor skills are associated with left-hemisphere specialization, whereas visuospatial skills are associated with right-hemisphere specialization. Individuals with autism spectrum conditions (ASC) show a profile of deficits and strengths that involves these lateralized cognitive functions. Here we test the hypothesis that regions implicated in these functions are atypically rightward lateralized in individuals with ASC and, that such atypicality is associated with functional performance. Participants included 67 male, right-handed adults with ASC and 69 age- and IQ-matched neurotypical males. We assessed group differences in structural asymmetries in cortical regions of interest with voxel-based analysis of grey matter volumes, followed by correlational analyses with measures of language, motor and visuospatial skills. We found stronger rightward lateralization within the inferior parietal lobule and reduced leftward lateralization extending along the auditory cortex comprising the planum temporale, Heschl's gyrus, posterior supramarginal gyrus, and parietal operculum, which was more pronounced in ASC individuals with delayed language onset compared to those without. Planned correlational analyses showed that for individuals with ASC, reduced leftward asymmetry in the auditory region was associated with more childhood social reciprocity difficulties. We conclude that atypical cerebral structural asymmetry is a potential candidate neurophenotype of ASC

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Mandy and Lai (2015) do the field a service in 'reclaiming' the role of pre- and postnatal environmental influences on the aetiology and course of autism spectrum conditions (ASC). This follows several decades where now discredited theories about putative psychogenic and biological disease models held sway, not least in the public mind. We discuss issues that arise from their review; including the need to identify how large the environmental influences on ASC are likely to be; the specificity of these environmental influences to ASC as opposed to a broader range of neurodevelopmental conditions and outcomes; how best to study complex interactions between genetic and environmental influences; and the promise of novel insights into their mechanisms of action. The review highlights current research that aims to better our understanding of the role of environmental factors in the aetiology and course of ASC and, in the near future, may offer the potential for personalised medicine approaches to intervention based on these discoveries.

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This study investigates effects of syntactic complexity operationalised in terms of movement, intervention and (NP) feature similarity in the development of A’ dependencies in 4-, 6-, and 8-year old typically developing (TD) French children and children with Autism Spectrum Disorders (ASD). Children completed an off-line comprehension task testing eight syntactic structures classified in four levels of complexity: Level 0: No Movement; Level 1: Movement without (configurational) Intervention; Level 2: Movement with Intervention from an element which is maximally different or featurally ‘disjoint’ (mismatched in both lexical NP restriction and number); Level 3: Movement with Intervention from an element similar in one feature or featurally ‘intersecting’ (matched in lexical NP restriction, mismatched in number). The results show that syntactic complexity affects TD children across the three age groups, but also indicate developmental differences between these groups. Movement affected all three groups in a similar way, but intervention effects in intersection cases were stronger in younger than older children, with NP feature similarity affecting only 4-year olds. Complexity effects created by the similarity in lexical restriction of an intervener thus appear to be overcome early in development, arguably thanks to other differences of this intervener (which was mismatched in number). Children with ASD performed less well than the TD children although they were matched on non-verbal reasoning. Overall, syntactic complexity affected their performance in a similar way as in their TD controls, but their performance correlated with non-verbal abilities rather than age, suggesting that their grammatical development does not follow the smooth relation to age that is found in TD children.

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As someone with Asperger's Syndrome, Wendy Lawson knows all about the social difficulties that accompany the condition. In this book, she guides others on the autism spectrum through the confusing map of life, tackling the building bricks of social existence one by one with humour, insight and practical suggestions. Exploring what it is like to be an adult in an alien world, she looks at the concepts of 'self' and 'other' and talks about the people in our lives -- how to relate to them, how we can use their support and how we can protect ourselves in the process. Using poetry and illustrations, she goes on to explain the difficult notion of putting on a face, looks at how to assess personal skills in order to develop them into a suitable career and how to deal with unwelcome changes in life. This book is essential reading for all those on the higher-functioning end of the autism spectrum, helping them to get the best out of a world that is often confusing and aiding those close to them to understand their perspective. Book jacket.

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Importance of the field: Autism is a severe, pervasive developmental disorder, the aetiology of which is poorly understood. Current pharmacological treatment options for autism are often focused on addressing comorbid behavioural problems, rather than core features of the disorder. Investigation of a new treatment approach is needed.

Areas covered in this review: Recent research has indicated a possible role of abnormalities in oxidative homeostasis in the pathophysiology of autism, based on reports that a range of oxidative biomarkers are significantly altered in people with autism. This article reviews the current findings on oxidative stress in autism, including genetic links to oxidative pathways, changes in antioxidant levels and other oxidative stress markers. We conducted a search of the literature up to June 2010, using Medline, Pubmed, PsycINFO, CINAHL PLUS and BIOSIS Previews.

What the reader will gain: This review provides an overview of the current understanding of the role of oxidative stress in autism. This will assist in highlighting areas of future therapeutic targets and potential underlying pathophysiology of this disorder.

Take home message: Abnormalities in oxidative homeostasis may play a role in the pathophysiology of autism. Antioxidant treatment may form a potential therapeutic pathway for this complex disorder.

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Background: Recent studies have suggested that oxytocin affects social cognition and behavior mediated by the oxytocin receptor (OXTR) in amygdala in humans as well as in experimental animals. Genetic studies have revealed a link between the OXTR gene and the susceptibility to autism spectrum disorders (ASD), especially in the social dysfunctional feature of ASD.

Methods: We examined the relationship between amygdala volume measured with manual tracing methodology and seven single nucleotide polymorphisms and one haplotype-block in OXTR, which were previously reported to be associated with ASD, in 208 socially intact Japanese adults with no neuropsychiatric history or current diagnosis.

Results: The rs2254298A allele of OXTR was significantly associated with larger bilateral amygdala volume. The rs2254298A allele effect on amygdala volume varied in proportion to the dose of this allele. The larger the number of rs2254298A alleles an individual had, the larger their amygdala volume. Such an association was not observed with hippocampal volume or with global brain volumes, including whole gray, white matter, and cerebrospinal-fluid space. Furthermore, two three–single nucleotide polymorphism haplotypes, including rs2254298G allele, showed significant associations with the smaller bilateral amygdala volume.

Conclusions: The present results suggest that OXTR might be associated with the susceptibility to ASD, especially in its aspects of social interaction and communication mediated by a modulation of amygdala development, one of the most distributed brain regions with high density of OXTR. Furthermore, amygdala volume measured with magnetic resonance imaging could be a useful intermediate phenotype to uncover the complex link between OXTR and social dysfunction in ASD.

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Previous researchers have postulated that gastrointestinal bacteria may contribute to the development and maintenance of Autism Spectrum Disorders (ASD). There is evidence based on quantitative evaluation of the gastrointestinal bacterial population in ASD that this is unlikely and an alternate mechanism will be examined where the bacteria may contribute to the development of ASD via their metabolic products and the role of biogenic amines (BAs) will be investigated. In humans, BAs influence a number of physiological processes via their actions as neurotransmitters, local hormones and gastric acid secretion. Various amines have been implicated in several medical conditions such as schizophrenia and colon cancer. To date, the relationship between BAs and autism has not been explored. This study has been designed to identify differences (and/or similarities) in the level of Bas in faecal samples of autistic children (without gastrointestinal dysfunction: n = 14; with gastrointestinal dysfunction; n = 21) and their neurotypical siblings (n = 35) by LC-MS/MS. Regardless of the diagnosis, severity of ASD and gastrointestinal dysfunction there were no significant differences found between the groups. The findings suggest that BAs in the gastrointestinal tract do not play a role in the pathophysiology of gastrointestinal dysfunction associated with ASD.

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Aripiprazole and risperidone are the only FDA approved medications for treating irritability in autistic disorder, however there are no head-to-head data comparing these agents. This is the first prospective randomized clinical trial comparing the safety and efficacy of these two medications in patients with autism spectrum disorders. Fifty nine children and adolescents with autism spectrum disorders were randomized to receive either aripiprazole or risperidone for 2 months. The primary outcome measure was change in Aberrant Behavior Checklist (ABC) scores. Adverse events were assessed. Aripiprazole as well as risperidone lowered ABC scores during 2 months. The rates of adverse effects were not significantly different between the two groups. The safety and efficacy of aripiprazole (mean dose 5.5 mg/day) and risperidone (mean dose 1.12 mg/day) were comparable. The choice between these two medications should be on the basis of clinical equipoise considering the patient's preference and clinical profile.

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BACKGROUND: Mitochondrial dysfunction and defects in oxidative metabolism are a characteristic feature of many chronic illnesses not currently classified as mitochondrial diseases. Examples of such illnesses include bipolar disorder, multiple sclerosis, Parkinson's disease, schizophrenia, depression, autism, and chronic fatigue syndrome. DISCUSSION: While the majority of patients with multiple sclerosis appear to have widespread mitochondrial dysfunction and impaired ATP production, the findings in patients diagnosed with Parkinson's disease, autism, depression, bipolar disorder schizophrenia and chronic fatigue syndrome are less consistent, likely reflecting the fact that these diagnoses do not represent a disease with a unitary pathogenesis and pathophysiology. However, investigations have revealed the presence of chronic oxidative stress to be an almost invariant finding in study cohorts of patients afforded each diagnosis. This state is characterized by elevated reactive oxygen and nitrogen species and/or reduced levels of glutathione, and goes hand in hand with chronic systemic inflammation with elevated levels of pro-inflammatory cytokines. SUMMARY: This paper details mechanisms by which elevated levels of reactive oxygen and nitrogen species together with elevated pro-inflammatory cytokines could conspire to pave a major road to the development of mitochondrial dysfunction and impaired oxidative metabolism seen in many patients diagnosed with these disorders.

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OBJECTIVES: People in the late stage of bipolar disorder (BD) experience elevated relapse rates and poorer quality of life (QoL) compared with those in the early stages. Existing psychological interventions also appear less effective in this group. To address this need, we developed a new online mindfulness-based intervention targeting quality of life (QoL) in late stage BD. Here, we report on an open pilot trial of ORBIT (online, recovery-focused, bipolar individual therapy). METHODS: Inclusion criteria were: self-reported primary diagnosis of BD, six or more episodes of BD, under the care of a medical practitioner, access to the internet, proficient in English, 18-65 years of age. Primary outcome was change (baseline - post-treatment) on the Brief QoL.BD (Michalak and Murray, 2010). Secondary outcomes were depression, anxiety, and stress measured on the DASS scales (Lovibond and Lovibond, 1993). RESULTS: Twenty-six people consented to participate (Age M=46.6 years, SD=12.9, and 75% female). Ten participants were lost to follow-up (38.5% attrition). Statistically significant improvement in QoL was found for the completers, t(15)=2.88, 95% CI:.89-5.98, p=.011, (Cohen׳s dz=.72, partial η(2)=.36), and the intent-to-treat sample t(25)=2.65, 95% CI:.47-3.76, (Cohen׳s dz=.52; partial η(2)=.22). A non-significant trend towards improvement was found on the DASS anxiety scale (p=.06) in both completer and intent-to-treat samples, but change on depression and stress did not approach significance. LIMITATIONS: This was an open trial with no comparison group, so measured improvements may not be due to specific elements of the intervention. Structured diagnostic assessments were not conducted, and interpretation of effectiveness was limited by substantial attrition. CONCLUSION: Online delivery of mindfulness-based psychological therapy for late stage BD appears feasible and effective, and ORBIT warrants full development. Modifications suggested by the pilot study include increasing the 3 weeks duration of the intervention, adding cautions about the impact of extended meditations, and addition of coaching support/monitoring to optimise engagement.

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We investigate the potential of a future kilometer-scale neutrino telescope, such as the proposed IceCube detector in the South Pole, to measure and disentangle the yet unknown components of the cosmic neutrino flux, the prompt atmospheric neutrinos coming from the decay of charmed particles and the extra-galactic neutrinos in the 10 TeV to 1 EeV energy range. Assuming a power law type spectra, dphi(nu)/dE(nu)similar toalphaE(nu)(beta), we quantify the discriminating power of the IceCube detector and discuss how well we can determine magnitude (alpha) as well as slope (beta) of these two components of the high energy neutrino spectrum, taking into account the background coming from the conventional atmospheric neutrinos.

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The Generator Coordinate Hartree-Fock (GCHF) Method is applied to generate extended 14s 8p and 17s 11p Gaussian basis sets for the atoms O and Si, respectively. The role of the weight functions in the assessment of the numerical integration range of the GCHF is shown. The Gaussian basis sets are contracted to [6s4p] O atom and [8s5p] Si atom by the Dunning's segmented contraction scheme. To evaluate the quality of our contracted [6s4p] and [8s5p] bases in molecular calculations we accomplish calculations of total and orbital energies in the Hartree-Fock-Roothaan method for O-2 and SiO molecules. We compare the results obtained with the our (14s 8p) and (17s 11p) bases sets with the of 6-311G basis and with values from the literature. The addition of one d polarization function in the silicon basis and its utilization with the basis for oxygen leads to the calculation of electronic properties and IR Spectrum of high tridymite in space group D-3d. (C) 1999 Elsevier B.V. B.V. All rights reserved.