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Autism spectrum disorder (ASD) and obsessive-compulsive disorder (OCD) often share phenotypes of repetitive behaviors, possibly underpinned by abnormal decision-making. To compare neural correlates underlying decision-making between these disorders, brain activation of boys with ASD (N = 24), OCD (N = 20) and typically developing controls (N = 20) during gambling was compared, and computational modeling compared performance. Patients were unimpaired on number of risky decisions, but modeling showed that both patient groups had lower choice consistency and relied less on reinforcement learning compared to controls. ASD individuals had disorder-specific choice perseverance abnormalities compared to OCD individuals. Neurofunctionally, ASD and OCD boys shared dorsolateral/inferior frontal underactivation compared to controls during decision-making. During outcome anticipation, patients shared underactivation compared to controls in lateral inferior/orbitofrontal cortex and ventral striatum. During reward receipt, ASD boys had disorder-specific enhanced activation in inferior frontal/insular regions relative to OCD boys and controls. Results showed that ASD and OCD individuals shared decision-making strategies that differed from controls to achieve comparable performance to controls. Patients showed shared abnormalities in lateral-(orbito)fronto-striatal reward circuitry, but ASD boys had disorder-specific lateral inferior frontal/insular overactivation, suggesting that shared and disorder-specific mechanisms underpin decision-making in these disorders. Findings provide evidence for shared neurobiological substrates that could serve as possible future biomarkers.

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Educational Psychology Research and Practice is an open access periodical published twice a year by the School of Psychology, University of East London. It offers a forum for informed debate and discussion of Educational Psychology research and training as well as a wider focus on issues of social justice and civic engagement in applied psychological practice. EPRaP is open to publishing research findings, literature reviews, commentaries, methodology papers, reflection on practice and book/resource reviews. It is part of a research and learning culture that recognises the importance of knowledge exchange and impact for partners in the community.

Little is known about the symptom profile of obsessive-compulsive disorder (OCD) in individuals who have autism spectrum disorders (ASD). It is also unknown whether self-report questionnaires are useful in measuring OCD in ASD. We sought to describe the symptom profiles of adults with ASD, OCD, and ASD + OCD using the Obsessive Compulsive Inventory-Revised (OCI-R), and to assess the utility of the OCI-R as a screening measure in a high-functioning adult ASD sample. Individuals with ASD (n = 171), OCD (n = 108), ASD + OCD (n = 54) and control participants (n = 92) completed the OCI-R. Individuals with ASD + OCD reported significantly higher levels of obsessive-compulsive symptoms than those with ASD alone. OCD symptoms were not significantly correlated with core ASD repetitive behaviors as measured on the ADI-R or ADOS-G. The OCI-R showed good psychometric properties and corresponded well with clinician diagnosis of OCD. Receiver operating characteristic analysis suggested cut-offs for OCI-R Total and Checking scores that discriminated well between ASD + versus –OCD, and fairly well between ASD-alone and OCD-alone. OCD manifests separately from ASD and is characterized by a different profile of repetitive thoughts and behaviors. The OCI-R appears to be useful as a screening tool in the ASD adult population.

Little is known about the symptom profile of obsessive-compulsive disorder (OCD) in individuals who have autism spectrum disorders (ASD). It is also unknown whether self-report questionnaires are useful in measuring OCD in ASD. We sought to describe the symptom profiles of adults with ASD, OCD, and ASD+OCD using the Obsessive Compulsive Inventory-Revised (OCI-R), and to assess the utility of the OCI-R as a screening measure in a high-functioning adult ASD sample. Individuals with ASD (n=171), OCD (n=108), ASD+OCD (n=54) and control participants (n=92) completed the OCI-R. Individuals with ASD+OCD reported significantly higher levels of obsessive-compulsive symptoms than those with ASD alone. OCD symptoms were not significantly correlated with core ASD repetitive behaviors as measured on the ADI-R or ADOS-G. The OCI-R showed good psychometric properties and corresponded well with clinician diagnosis of OCD. Receiver operating characteristic analysis suggested cut-offs for OCI-R Total and Checking scores that discriminated well between ASD+versus -OCD, and fairly well between ASD-alone and OCD-alone. OCD manifests separately from ASD and is characterized by a different profile of repetitive thoughts and behaviors. The OCI-R appears to be useful as a screening tool in the ASD adult population. © 2015 International Society for Autism Research, Wiley Periodicals, Inc. 8 5 477 485 Cited By :9; Export Date: 17 July 2017

BackgroundIncreasing evidence suggests that autism is associated with abnormal white-matter (WM) anatomy and impaired brain ‘connectivity’. While myelin plays a critical role in synchronized brain communication, its aetiological role in autistic symptoms has only been indirectly addressed by WM volumetric, relaxometry and diffusion tensor imaging studies. A potentially more specific measure of myelin content, termed myelin water fraction (MWF), could provide improved sensitivity to myelin alteration in autism.MethodWe performed a cross-sectional imaging study that compared 14 individuals with autism and 14 age- and IQ-matched controls. T1 relaxation times (T1), T2 relaxation times (T2) and MWF values were compared between autistic subjects, diagnosed using the Autism Diagnostic Interview – Revised (ADI-R), with current symptoms assessed using the Autism Diagnostic Observation Schedule (ADOS) and typical healthy controls. Correlations between T1, T2 and MWF values with clinical measures [ADI-R, ADOS, and the Autism Quotient (AQ)] were also assessed.ResultsIndividuals with autism showed widespread WM T1 and MWF differences compared to typical controls. Within autistic individuals, worse current social interaction skill as measured by the ADOS was related to reduced MWF although not T1. No significant differences or correlations with symptoms were observed with respect to T2.ConclusionsAutistic individuals have significantly lower global MWF and higher T1, suggesting widespread alteration in tissue microstructure and biochemistry. Areas of difference, including thalamic projections, cerebellum and cingulum, have previously been implicated in the disorder; however, this is the first study to specifically indicate myelin alteration in these regions.

Objective: Sustained attention problems are common in people with autism spectrum disorder (ASD) and may have significant implications for the diagnosis and management of ASD and associated comorbidities. Furthermore, ASD has been associated with atypical structural brain development. The authors used functional MRI to investigate the functional brain maturation of attention between childhood and adulthood in people with ASD. Method: Using a parametrically modulated sustained attention/vigilance task, the authors examined brain activation and its linear correlation with age between childhood and adulthood in 46 healthy male adolescents and adults (ages 11-35 years) with ASD and 44 age- and IQ-matched typically developing comparison subjects. Results: Relative to the comparison group, the ASD group had significantly poorer task performance and significantly lower activation in inferior prefrontal cortical, medial prefrontal cortical, striato-thalamic, and lateral cerebellar regions. A conjunction analysis of this analysis with group differences in brain-age correlations showed that the comparison group, but not the ASD group, had significantly progressively increased activation with age in these regions between childhood and adulthood, suggesting abnormal functional brain maturation in ASD. Several regions that showed both abnormal activation and functional maturation were associated with poorer task performance and clinical measures of ASD and inattention. Conclusions: The results provide first evidence that abnormalities in sustained attention networks in individuals with ASD are associated with underlying abnormalities in the functional brain maturation of these networks between late childhood and adulthood. © 2014, American Psychiatric Association. All rights reserved. 171 10 1107 1116 Cited By :10; Export Date: 17 July 2017

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Autism spectrum disorders (ASD) are a group of neurodevelopmental conditions that are accompanied by atypical brain connectivity. So far, in vivo evidence for atypical structural brain connectivity in ASD has mainly been based on neuroimaging studies of cortical white matter. However, genetic studies suggest that abnormal connectivity in ASD may also affect neural connections within the cortical gray matter. Such intrinsic gray-matter connections are inherently more difficult to describe in vivo but may be inferred from a variety of surface-based geometric features that can be measured using magnetic resonance imaging. Here, we present a neuroimaging study that examines the intrinsic cortico-cortical connectivity of the brain in ASD using measures of “cortical separation distances” to assess the global and local intrinsic “wiring costs” of the cortex (i.e., estimated length of horizontal connections required to wire the cortex within the cortical sheet). In a sample of 68 adults with ASD and matched controls, we observed significantly reduced intrinsic wiring costs of cortex in ASD, both globally and locally. Differences in global and local wiring cost were predominantly observed in fronto-temporal regions and also significantly predicted the severity of social and repetitive symptoms (respectively). Our study confirms that atypical cortico-cortical “connectivity” in ASD is not restricted to the development of white-matter connections but may also affect the intrinsic gray-matter architecture (and connectivity) within the cortical sheet. Thus, the atypical connectivity of the brain in ASD is complex, affecting both gray and white matter, and forms part of the core neural substrates underlying autistic symptoms.

Antisocial personality disorder (ASPD) and psychopathy involve significant interpersonal and behavioural impairments. However, little is known about their underlying neurobiology and in particular, abnormalities in white matter (WM) microstructure. Apreliminary diffusion tensor magnetic resonance imaging (DT-MRI) study of adult psychopaths employing tractography revealed abnormalities in the right uncinate fasciculus (UF) (Craig et al., 2009), indicating fronto-limbic disconnectivity. However, it is not clear whether WM abnormalities are restricted to this tract or are or more widespread, including other tracts which are involved in connectivity with the frontal lobe.We performed whole brain voxel-based analyses on WM fractional anisotropy (FA) and mean diffusivity (MD) maps acquired with DT-MRI to compare 15 adults with ASPD and healthy age, handedness and IQ-matched controls. Also, within ASPD subjects we related differences in FA and MD to measures of psychopathy.Significant WM FA reduction and MD increases were found respectively in ASPD subjects relative to controls. FA was bilaterally reduced in the genu of corpus callosum while in the right frontal lobe FA reduction was found in the UF, inferior fronto-occipital fasciculus (IFOF), anterior corona radiata and anterior limb and genu of the internal capsule. These differences negatively correlated with measures of psychopathy. Also in the right frontal lobe, increased MD was found in the IFOF and UF, and the corpus callosum and anterior corona radiata. There was a significant positive correlation between MD and psychopathy scores. Conclusions: The present study confirms a previous report of reduced FA in the UF. Additionally, we report for the first time, FA deficits in tracts involved in interhemispheric as well as frontal lobe connectivity in conjunction with MD increases in the frontal lobe. Hence, we provide evidence of significant WM microstructural abnormalities in frontal brain regions in ASPD and psychopathy. © 2011 Elsevier Srl. 48 2 216 229 Cited By :51; Export Date: 17 July 2017

The statistical Bayesian and descriptive regularization approaches for high resolution radar image formation is detailed in many works; here we refer to [1]–[3] where such approach is adapted to the sm and mm waveband remote sensing (RS) applications considered in this paper. An alternative approach to image enhancement and noise suppression was proposed and detailed in [4] where the variational analysis (VA) paradigm was employed to incorporate a priori information regarding the image geometrical properties specified by its gradient flow over the image frame, while no particular model of the imaging system was employed. In view of this, the VA paradigm may be classified as a system model-free image enhancement approach [1], [4]. Some second order partial differential equation (PDE) models for specifying the gradient flow over the image frame were employed in different VA approaches to incorporate the intrinsic image geometry properties into the enhancement procedures [4], [6], [7]. The crucial limitation of all VA-based methods lies in their descriptive system-model-free deterministic regularization nature because these methods do not employ statistical optimization strategies. In view of this, the following problem arises: how to aggregate the statistically optimal Bayesian minimum risk (BME) convex regularization method with the VA formalism for enhanced RS imaging that incorporate the advantages of both the VA and the statistical convex regularization (CR) approaches. In this paper, we address a novel aggregated VA and statistical CR fusion paradigm that leads to a new method addressed to as the fused convex regularization variational analysis (CRVA) technique. The VA paradigm is adapted via incorporating the imaging scene spatial spectrum pattern (SSP) gradient norm preservation [1] into the overall CR image reconstruction problem to control the geometrical properties of the desired solution.