1. Breen J, Hare DJ. {{The nature and prevalence of catatonic symptoms in young people with autism}}. {J Intellect Disabil Res};2017 (Feb 01)
BACKGROUND: A proportion of young people with autism are reported to show catatonic-like symptoms in adolescence. The aetiology and prevalence of such presentations is unknown but include a set of behaviours that can best be described as attenuated. METHOD: The current study empirically investigated the presence and nature of such attenuated behaviours in children and adolescents with autism using a newly developed 34-item third party report measure, the Attenuated Behaviour Questionnaire. Caregivers or parents of young people with autism reported on the presentation of symptoms via the online completion of the Attenuated Behaviour Questionnaire and two established clinical measures of repetitive behaviour and depression. RESULTS: Initial results indicate that the Attenuated Behaviour Questionnaire is a workable clinical measure in this population with a degree of discriminant validity with regard to catatonia. Attenuated behaviour indicative of catatonia was relatively common in young people with autism with up to 20.2% having an existing diagnosis of catatonia and evidence of a relationship between attenuated behaviours and measures of depression and repetitive and restricted behaviours. CONCLUSION: Catatonic symptoms are more prevalent in young people with autism than previously thought, and the Attenuated Behaviour Questionnaire has potential as a clinical and research tool.
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2. Carper RA, Treiber JM, White NS, Kohli JS, Muller RA. {{Restriction Spectrum Imaging As a Potential Measure of Cortical Neurite Density in Autism}}. {Front Neurosci};2016;10:610.
Autism postmortem studies have shown various cytoarchitectural anomalies in cortical and limbic areas including increased cell packing density, laminar disorganization, and narrowed minicolumns. However, there is little evidence on dendritic and axonal organization in ASD. Recent imaging techniques have the potential for non-invasive, in vivo studies of small-scale structure in the human brain, including gray matter. Here, Restriction Spectrum Imaging (RSI), a multi-shell diffusion-weighted imaging technique, was used to examine gray matter microstructure in 24 children with ASD (5 female) and 20 matched typically developing (TD) participants (2 female), ages 7-17 years. RSI extends the spherical deconvolution model to multiple length scales to characterize neurite density (ND) and organization. Measures were examined in 48 cortical regions of interest per hemisphere. To our knowledge, this is the first time that a multi-compartmental diffusion model has been applied to cortical gray matter in ASD. The ND measure detected robust age effects showing a significant positive relationship to age in all lobes except left temporal when groups were combined. Results were also suggestive of group differences (ASD
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3. Gu F, Chauhan V, Chauhan A. {{Monoamine oxidase-A and B activities in the cerebellum and frontal cortex of children and young adults with autism}}. {J Neurosci Res};2017 (Feb 02)
Monoamine oxidases (MAOs) catalyze the metabolism of monoamine neurotransmitters, such as serotonin, dopamine, and norepinephrine, and are key regulators for brain function. In this study, we analyzed the activities of MAO-A and MAO-B in the cerebellum and frontal cortex from subjects with autism and age-matched control subjects. In the cerebellum, MAO-A activity in subjects with autism (aged 4-38 years) was significantly lower by 20.6% than in controls. When the subjects were divided into children (aged 4-12 years) and young adults (aged 13-38 years) subgroups, a significant decrease by 27.8% in the MAO-A activity was observed only in children with autism compared with controls. When the 95% confidence interval of the control group was taken as a reference range, reduced activity of MAO-A was observed in 70% of children with autism. In the frontal cortex, MAO-A activity in children with autism was also lower by 30% than in the control group, and impaired activity of MAO-A was observed in 55.6% of children with autism, although the difference between the autism and control groups was not significant when all subjects were considered. On the contrary, there was no significant difference in MAO-B activity in both the cerebellum and frontal cortex between children with autism and the control group as well as in adults. These results suggest impaired MAO-A activity in the brain of subjects with autism, especially in children with autism. Decreased activity of MAOs may lead to increased levels of monoaminergic neurotransmitters, such as serotonin, which have been suggested to have a critical role in autism. (c) 2017 Wiley Periodicals, Inc.
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4. Ingersoll BR, Wainer AL, Berger NI, Walton KM. {{Efficacy of low intensity, therapist-implemented Project ImPACT for increasing social communication skills in young children with ASD}}. {Dev Neurorehabil};2017 (Feb 02):1-9.
Project ImPACT is a Naturalistic Developmental Behavioral Intervention (NDBI) for young children with ASD. Preliminary research supports its feasibility and efficacy as a parent-mediated intervention; however, its efficacy as a low-intensity, therapist-implemented intervention is unclear. A single-case, multiple-baseline design evaluated the effect of 2 h per week of therapist-implemented Project ImPACT on social engagement, language, and play in nine children with ASD. Language and play skills were targeted separately for five children and together for four children. Children increased their rates of social engagement and language when language or play was the sole target and when language and play were targeted together; however, gains in play skills were evident only when they were targeted separately. This study provides support for the efficacy of the Project ImPACT when implemented by therapists at a low intensity and suggests the way in which skills are targeted can affect child learning.
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5. Jack A, Keifer CM, Pelphrey KA. {{Cerebellar contributions to biological motion perception in autism and typical development}}. {Hum Brain Mapp};2017 (Feb 02)
Growing evidence suggests that posterior cerebellar lobe contributes to social perception in healthy adults. However, they know little about how this process varies across age and with development. Using cross-sectional fMRI data, they examined cerebellar response to biological (BIO) versus scrambled (SCRAM) motion within typically developing (TD) and autism spectrum disorder (ASD) samples (age 4-30 years old), characterizing cerebellar response and BIO > SCRAM-selective effective connectivity, as well as associations with age and social ability. TD individuals recruited regions throughout cerebellar posterior lobe during BIO > SCRAM, especially bilateral lobule VI, and demonstrated connectivity with right posterior superior temporal sulcus (RpSTS) in left VI, Crus I/II, and VIIIb. ASD individuals showed BIO > SCRAM activity in left VI and left Crus I/II, and bilateral connectivity with RpSTS in Crus I/II and VIIIb/IX. No between-group differences emerged in well-matched subsamples. Among TD individuals, older age predicted greater BIO > SCRAM response in left VIIb and left VIIIa/b, but reduced connectivity between RpSTS and widespread regions of the right cerebellum. In ASD, older age predicted greater response in left Crus I and bilateral Crus II, but decreased effective connectivity with RpSTS in bilateral Crus I/II. In ASD, increased BIO > SCRAM signal in left VI/Crus I and right Crus II, VIIb, and dentate predicted lower social symptomaticity; increased effective connectivity with RpSTS in right Crus I/II and bilateral VI and I-V predicted greater symptomaticity. These data suggest that posterior cerebellum contributes to the neurodevelopment of social perception in both basic and clinical populations. Hum Brain Mapp, 2017. (c) 2017 Wiley Periodicals, Inc.
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6. Kincaid DL, Doris M, Shannon C, Mulholland C. {{What is the prevalence of autism spectrum disorder and ASD traits in psychosis? A systematic review}}. {Psychiatry Res};2017 (Jan 07);250:99-105.
There is increasing evidence to suggest both a symptomatic overlap and a clinically significant degree of co-occurrence between Autism Spectrum Disorders (ASD) and psychotic disorders such as schizophrenia but the nature of such relationships remain unclear. We reviewed the literature reporting prevalence rates of Autistic-like Traits (ALTs) and ASD in populations with a diagnosis of schizophrenia or other psychotic disorder. A search of three large databases was conducted and from this seven studies met the criteria for inclusion. The point prevalence rates for ALTs ranged from 9.6% to 61%, whilst the prevalence rates for diagnosed ASD ranged from <1% to 52% across outpatient and inpatient populations. This suggests that prevalence rates of ALTs and ASD in psychosis populations are much higher than in the general population. This has important implications regarding future research, and clinical implications in terms of ensuring that patients receive the most appropriate diagnosis and treatment. Lien vers le texte intégral (Open Access ou abonnement)
7. Laycock R, Chan D, Crewther SG. {{Attention Orienting in Response to Non-conscious Hierarchical Arrows: Individuals with Higher Autistic Traits Differ in Their Global/Local Bias}}. {Front Psychol};2017;8:23.
One aspect of the social communication impairments that characterize autism spectrum disorder (ASD) include reduced use of often subtle non-verbal social cues. People with ASD, and those with self-reported sub-threshold autistic traits, also show impairments in rapid visual processing of stimuli unrelated to social or emotional properties. Hence, this study sought to investigate whether perceptually non-conscious visual processing is related to autistic traits. A neurotypical sample of thirty young adults completed the Subthreshold Autism Trait Questionnaire and a Posner-like attention cueing task. Continuous Flash Suppression (CFS) was employed to render incongruous hierarchical arrow cues perceptually invisible prior to consciously presented targets. This was achieved via a 10 Hz masking stimulus presented to the dominant eye that suppressed information presented to the non-dominant eye. Non-conscious arrows consisted of local arrow elements pointing in one direction, and forming a global arrow shape pointing in the opposite direction. On each trial, the cue provided either a valid or invalid cue for the spatial location of the subsequent target, depending on which level (global or local) received privileged attention. A significant autism-trait group by global cue validity interaction indicated a difference in the extent of non-conscious local/global cueing between groups. Simple effect analyses revealed that whilst participants with lower autistic traits showed a global arrow cueing effect, those with higher autistic traits demonstrated a small local arrow cueing effect. These results suggest that non-conscious processing biases in local/global attention may be related to individual differences in autistic traits.
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8. Marchant S, Gillani R, Serwint J. {{Case 1: Leg and Hip Pain in an 8-year-old Boy with Autism}}. {Pediatr Rev};2017 (Feb);38(2):93-94.
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9. Mucerino S, Di Salle A, Alessio N, Margarucci S, Nicolai R, Melone MA, Galderisi U, Peluso G. {{Alterations in the carnitine cycle in a mouse model of Rett syndrome}}. {Sci Rep};2017 (Feb 02);7:41824.
Rett syndrome (RTT) is a neurodevelopmental disease that leads to intellectual deficit, motor disability, epilepsy and increased risk of sudden death. Although in up to 95% of cases this disease is caused by de novo loss-of-function mutations in the X-linked methyl-CpG binding protein 2 gene, it is a multisystem disease associated also with mitochondrial metabolic imbalance. In addition, the presence of long QT intervals (LQT) on the patients’ electrocardiograms has been associated with the development of ventricular tachyarrhythmias and sudden death. In the attempt to shed light on the mechanism underlying heart failure in RTT, we investigated the contribution of the carnitine cycle to the onset of mitochondrial dysfunction in the cardiac tissues of two subgroups of RTT mice, namely Mecp2+/- NQTc and Mecp2+/- LQTc mice, that have a normal and an LQT interval, respectively. We found that carnitine palmitoyltransferase 1 A/B and carnitine acylcarnitine translocase were significantly upregulated at mRNA and protein level in the heart of Mecp2+/- mice. Moreover, the carnitine system was imbalanced in Mecp2+/- LQTc mice due to decreased carnitine acylcarnitine transferase expression. By causing accumulation of intramitochondrial acylcarnitines, this imbalance exacerbated incomplete fatty acid oxidation, which, in turn, could contribute to mitochondrial overload and sudden death.
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10. Vyas K, Jameel L, Bellesi G, Crawford S, Channon S. {{Derailing the trolley: Everyday utilitarian judgments in groups high versus low in psychopathic traits or autistic traits}}. {Psychiatry Res};2017 (Jan 22);250:84-91.
Moral decision-making has been linked with empathy. The present study built on previous work examining the relationship between psychopathy or autism spectrum disorder (ASD), two conditions putatively associated with deficits in empathy, and utilitarian decision-making. Students scoring high on self-report measures of psychopathic or autistic traits were presented with a novel task, ‘Utilitarian Judgments’, and compared to low trait control groups. This study replicated the classic finding that more direct links between the agents’ actions and harm to victims mitigated utilitarian decision-making. It also found that participants made more utilitarian decisions when outcomes involved extreme physical versus everyday social harm. Enhanced utilitarian decision-making was not observed in those scoring high for either psychopathic or autistic traits, although both high trait groups reported that they would experience less discomfort than their low trait counterparts. Verbal reasoning differences were observed for the high autistic trait group, but not the high psychopathic trait group. The dilemmas that have been typically used to explore utilitarian decision-making describe extreme, hypothetical events involving physical or serious emotional harm. The present findings suggest that this might limit the generalisability of the existing literature and over-emphasise the tendency to make utilitarian decisions when considering everyday dilemmas.
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11. Zhu Y, Zhu X, Zhang H, Gao W, Shen D, Wu G. {{Reveal Consistent Spatial-Temporal Patterns from Dynamic Functional Connectivity for Autism Spectrum Disorder Identification}}. {Med Image Comput Comput Assist Interv};2016 (Oct);9900:106-114.
Functional magnetic resonance imaging (fMRI) provides a non-invasive way to investigate brain activity. Recently, convergent evidence shows that the correlations of spontaneous fluctuations between two distinct brain regions dynamically change even in resting state, due to the condition-dependent nature of brain activity. Thus, quantifying the patterns of functional connectivity (FC) in a short time period and changes of FC over time can potentially provide valuable insight into both individual-based diagnosis and group comparison. In light of this, we propose a novel computational method to robustly estimate both static and dynamic spatial-temporal connectivity patterns from the observed noisy signals of individual subject. We achieve this goal in two folds: (1) Construct static functional connectivity across brain regions. Due to low signal-to-noise ratio induced by possible non-neural noise, the estimated FC strength is very sensitive and it is hard to define a good threshold to distinguish between real and spurious connections. To alleviate this issue, we propose to optimize FC which is in consensus with not only the low level region-to-region signal correlations but also the similarity of high level principal connection patterns learned from the estimated link-to-link connections. Since brain network is intrinsically sparse, we also encourage sparsity during FC optimization. (2) Characterize dynamic functional connectivity along time. It is hard to synchronize the estimated dynamic FC patterns and the real cognitive state changes, even using learning-based methods. To address these limitations, we further extend above FC optimization method into the spatial-temporal domain by arranging the FC estimations along a set of overlapped sliding windows into a tensor structure as the window slides. Then we employ low rank constraint in the temporal domain assuming there are likely a small number of discrete states that the brain transverses during a short period of time. We applied the learned spatial-temporal patterns from fMRI images to identify autism subjects. Promising classification results have been achieved, suggesting high discrimination power and great potentials in computer assisted diagnosis.
