1. Bishop SL, Veenstra-VanderWeele J, Sanders SJ. {{Attention Finally Being Paid to Girls at Risk of Autism}}. {J Am Acad Child Adolesc Psychiatry};2016 (Mar);55(3):159-160.
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2. Chawarska K, Macari S, Powell K, DiNicola L, Shic F. {{Enhanced Social Attention in Female Infant Siblings at Risk for Autism}}. {J Am Acad Child Adolesc Psychiatry};2016 (Mar);55(3):188-195 e181.
OBJECTIVE: Sexual dimorphism in autism spectrum disorders (ASD) is a well-recognized but poorly understood phenomenon. Females are four times less likely to be diagnosed with ASD than males and, when diagnosed, are more likely to exhibit comorbid anxiety symptoms. One of the key phenotypic features of ASD is atypical attention to socially relevant stimuli. Eye-tracking studies indicate atypical patterns of spontaneous social orienting during the prodromal and early syndromic stages of ASD. However, there have been no studies evaluating sex differences in early social orienting and their potential contribution to later outcomes. METHOD: We examined sex differences in social orienting in 6-, 9-, and 12-month-old infants at high genetic risk for ASD (n = 101) and in low-risk controls (n = 61), focusing on neurobehavioral measures of function across a spectrum of autism risk. RESULTS: Results suggest that, between 6 and 12 months of age, a period highly consequential for the development of nonverbal social engagement competencies, high-risk females show enhanced attention to social targets, including faces, compared to both high-risk males and low-risk males and females. Greater attention to social targets in high-risk infants was associated with less severe social impairments at 2 years. CONCLUSION: The results suggest an alternative expression of autism risk in females, which manifests in infancy as increased attention toward socially relevant stimuli. This increased attention may serve as a female protective factor against ASD by providing increased access to social experiences in early development.
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3. Chen CH, Liao HM, Chen HI, Fang JS, Chen YJ, Lee KF, Gau SS. {{Complex genomic variants contribute toward the genetic architecture of autism spectrum disorder}}. {Psychiatr Genet};2016 (Apr);26(2):95-96.
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4. Chen PJ, Gau SS, Lee SH, Chou TL. {{Differences in age-dependent neural correlates of semantic processing between youths with autism spectrum disorder and typically developing youths}}. {Autism Res};2016 (Feb 21)
Individuals with autism spectrum disorders (ASD) have aberrant neural activity during semantic judgments. We aimed to examine age-dependent neural correlates of semantic processing in boys with ASD as compared to typically developing boys (TD). We used functional MRI to investigate 37 boys with ASD (mean age = 13.3 years, standard deviation = 2.4) and 35 age-, sex-, Intelligence quotient (IQ)- and handedness-matched TD boys (mean age = 13.3 years, standard deviation = 2.7) from age 8 to 18 years. Participants had to indicate whether pairs of Chinese characters presented visually were related in meaning. Group (ASD, TD) x Age (Old, Young) ANOVA was used to examine the difference of age-related changes. Direct comparisons between the adolescent group and the child group were also performed. The behavioral results showed that the ASD group had lower accuracy in the related condition relative to the TD group. The neuroimaging results showed greater activation in the cuneus and less activation in the left inferior frontal gyrus in boys with ASD than TD boys. Children with ASD produced greater activation in the cuneus than TD children. Adolescents with ASD showed reduced left IFG activation as compared to TD adolescents. Our findings suggest that TD boys may engage more in higher-level processing of retrieving or selecting semantic features while boys with ASD may rely more on lower-level visual processing during semantic judgments. The findings imply different functional organizations of the semantic system between the two groups. Autism Res 2016. (c) 2016 International Society for Autism Research, Wiley Periodicals, Inc.
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5. Cooper RA, Plaisted-Grant KC, Baron-Cohen S, Simons JS. {{Reality Monitoring and Metamemory in Adults with Autism Spectrum Conditions}}. {J Autism Dev Disord};2016 (Feb 22)
Studies of reality monitoring (RM) often implicate medial prefrontal cortex (mPFC) in distinguishing internal and external information, a region linked to autism-related deficits in social and self-referential information processing, executive function, and memory. This study used two RM conditions (self-other; perceived-imagined) to investigate RM and metamemory in adults with autism. The autism group showed a deficit in RM, which did not differ across source conditions, and both groups exhibited a self-encoding benefit on recognition and source memory. Metamemory for perceived-imagined information, but not for self-other information, was significantly lower in the autism group. Therefore, reality monitoring and metamemory, sensitive to mPFC function, appear impaired in autism, highlighting a difficulty in remembering and monitoring internal and external details of past events.
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6. Eberhardt M, Nadig A. {{Reduced sensitivity to context in language comprehension: A characteristic of Autism Spectrum Disorders or of poor structural language ability?}}. {Res Dev Disabil};2016 (Feb 18)
We present two experiments examining the universality and uniqueness of reduced context sensitivity in language processing in Autism Spectrum Disorders (ASD), as proposed by the Weak Central Coherence account (Happe & Frith, 2006, Journal of Autism and Developmental Disorders, 36(1), 25). That is, do all children with ASD exhibit decreased context sensitivity, and is this characteristic specific to ASD versus other neurodevelopmental conditions? Experiment 1, conducted in English, was a comparison of children with ASD with normal language and their typically-developing peers on a picture selection task where interpretation of sentential context was required to identify homonyms. Contrary to the predictions of Weak Central Coherence, the ASD-normal language group exhibited no difficulty on this task. Experiment 2, conducted in German, compared children with ASD with variable language abilities, typically-developing children, and a second control group of children with Language Impairment (LI) on a sentence completion task where a context sentence had to be considered to produce the continuation of an ambiguous sentence fragment. Both ASD-variable language and LI groups exhibited reduced context sensitivity and did not differ from each other. Finally, to directly test which factors contribute to reduced context sensitivity, we conducted a regression analysis for each experiment, entering nonverbal IQ, structural language ability, and autism diagnosis as predictors. For both experiments structural language ability emerged as the only significant predictor. These convergent findings demonstrate that reduced sensitivity to context in language processing is linked to low structural language rather than ASD diagnosis.
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7. Fuccillo MV. {{Striatal Circuits as a Common Node for Autism Pathophysiology}}. {Front Neurosci};2016;10:27.
Autism spectrum disorders (ASD) are characterized by two seemingly unrelated symptom domains-deficits in social interactions and restrictive, repetitive patterns of behavioral output. Whether the diverse nature of ASD symptomatology represents distributed dysfunction of brain networks or abnormalities within specific neural circuits is unclear. Striatal dysfunction is postulated to underlie the repetitive motor behaviors seen in ASD, and neurological and brain-imaging studies have supported this assumption. However, as our appreciation of striatal function expands to include regulation of behavioral flexibility, motivational state, goal-directed learning, and attention, we consider whether alterations in striatal physiology are a central node mediating a range of autism-associated behaviors, including social and cognitive deficits that are hallmarks of the disease. This review investigates multiple genetic mouse models of ASD to explore whether abnormalities in striatal circuits constitute a common pathophysiological mechanism in the development of autism-related behaviors. Despite the heterogeneity of genetic insult investigated, numerous genetic ASD models display alterations in the structure and function of striatal circuits, as well as abnormal behaviors including repetitive grooming, stereotypic motor routines, deficits in social interaction and decision-making. Comparative analysis in rodents provides a unique opportunity to leverage growing genetic association data to reveal canonical neural circuits whose dysfunction directly contributes to discrete aspects of ASD symptomatology. The description of such circuits could provide both organizing principles for understanding the complex genetic etiology of ASD as well as novel treatment routes. Furthermore, this focus on striatal mechanisms of behavioral regulation may also prove useful for exploring the pathogenesis of other neuropsychiatric diseases, which display overlapping behavioral deficits with ASD.
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8. Gardner M, Suplee PD, Bloch J, Lecks K. {{Exploratory Study of Childbearing Experiences of Women With Asperger Syndrome}}. {Nurs Womens Health};2016 (Feb-Mar);20(1):28-37.
Increasing numbers of girls have been diagnosed with Asperger syndrome and other autism spectrum disorders (ASDs) over the past two decades; therefore, more women with ASDs are entering the childbearing phase of their lives. Little is known about the childbearing experiences of women with ASDs. This qualitative study describes the childbearing experiences of eight women with Asperger syndrome. Four major themes emerged: Processing Sensations, Needing to Have Control, Walking in the Dark, and Motherhood on My Own Terms. Clinicians can provide sensitive, individualized care by asking women with Asperger syndrome about their specific sensory experiences, counseling them about coping strategies for sensory intrusions, providing targeted support, and modifying the clinical environment to decrease distressing stimuli.
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9. Jin Y, Wee CY, Shi F, Thung KH, Yap PT, Shen D. {{Identification of Infants at Risk for Autism Using Multi-parameter Hierarchical White Matter Connectomes}}. {Mach Learn Med Imaging};2015;9352:170-177.
Autism spectrum disorder (ASD) is a variety of developmental disorders that cause life-long communication and social deficits. However, ASD could only be diagnosed at children as early as 2 years of age, while early signs may emerge within the first year. White matter (WM) connectivity abnormalities have been documented in the first year of lives of ASD subjects. We introduce a novel multi-kernel support vector machine (SVM) framework to identify infants at high-risk for ASD at 6 months old, by utilizing the diffusion parameters derived from a hierarchical set of WM connectomes. Experiments show that the proposed method achieves an accuracy of 76%, in comparison to 70% with the best single connectome. The complementary information extracted from hierarchical networks enhances the classification performance, with the top discriminative connections consistent with other studies. Our framework provides essential imaging connectomic markers and contributes to the evaluation of ASD risks as early as 6 months.
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10. Moos WH, Maneta E, Pinkert CA, Irwin MH, Hoffman ME, Faller DV, Steliou K. {{Epigenetic Treatment of Neuropsychiatric Disorders: Autism and Schizophrenia}}. {Drug Dev Res};2016 (Feb 21)
Preclinical Research Neuropsychiatric disorders are a heterogeneous group of conditions that often share underlying mitochondrial dysfunction and biological pathways implicated in their pathogenesis, progression, and treatment. To date, these disorders have proven notoriously resistant to molecular-targeted therapies, and clinical options are relegated to interventional types, which do not address the core symptoms of the disease. In this review, we discuss emerging epigenetic-driven approaches using novel acylcarnitine esters (carnitinoids) that act on master regulators of antioxidant and cytoprotective genes and mitophagic pathways. These carnitinoids are actively transported, mitochondria-localizing, biomimetic coenzyme A surrogates of short-chain fatty acids, which inhibit histone deacetylase and may reinvigorate synaptic plasticity and protect against neuronal damage. We outline these neuroprotective effects in the context of treatment of neuropsychiatric disorders such as autism spectrum disorder and schizophrenia. Drug Dev Res, 2016. (c) 2016 Wiley Periodicals, Inc.
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11. Petrelli F, Pucci L, Bezzi P. {{Astrocytes and Microglia and Their Potential Link with Autism Spectrum Disorders}}. {Front Cell Neurosci};2016;10:21.
The cellular mechanism(s) underlying autism spectrum disorders (ASDs) are not fully understood although it has been shown that various genetic and environmental factors contribute to their etiology. As increasing evidence indicates that astrocytes and microglial cells play a major role in synapse maturation and function, and there is evidence of deficits in glial cell functions in ASDs, one current hypothesis is that glial dysfunctions directly contribute to their pathophysiology. The aim of this review is to summarize microglia and astrocyte functions in synapse development and their contributions to ASDs.
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12. Rothwell PE. {{Autism Spectrum Disorders and Drug Addiction: Common Pathways, Common Molecules, Distinct Disorders?}}. {Front Neurosci};2016;10:20.
Autism spectrum disorders (ASDs) and drug addiction do not share substantial comorbidity or obvious similarities in etiology or symptomatology. It is thus surprising that a number of recent studies implicate overlapping neural circuits and molecular signaling pathways in both disorders. The purpose of this review is to highlight this emerging intersection and consider implications for understanding the pathophysiology of these seemingly distinct disorders. One area of overlap involves neural circuits and neuromodulatory systems in the striatum and basal ganglia, which play an established role in addiction and reward but are increasingly implicated in clinical and preclinical studies of ASDs. A second area of overlap relates to molecules like Fragile X mental retardation protein (FMRP) and methyl CpG-binding protein-2 (MECP2), which are best known for their contribution to the pathogenesis of syndromic ASDs, but have recently been shown to regulate behavioral and neurobiological responses to addictive drug exposure. These shared pathways and molecules point to common dimensions of behavioral dysfunction, including the repetition of behavioral patterns and aberrant reward processing. The synthesis of knowledge gained through parallel investigations of ASDs and addiction may inspire the design of new therapeutic interventions to correct common elements of striatal dysfunction.
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13. Shan L, Hu XL, Wang B, Jia FY. {{[Research advances in the role of vitamin D in autism spectrum disorders]}}. {Zhongguo Dang Dai Er Ke Za Zhi};2016 (Feb);18(2):183-188.
The etiology and pathogenic mechanism of autism spectrum disorders (ASD) are still unclear. The relationship between vitamin D and ASD has drawn attention in recent years due to common vitamin D deficiency in children with ASD. This article reviews the peripheral blood levels of vitamin D in children with ASD, the possible reasons for hypovitamin D and its possible roles in the etiology of ASD and the efficacy of vitamin D supplementation in ASD.
14. Singh NN, Lancioni GE, Karazsia BT, Myers RE. {{Caregiver Training in Mindfulness-Based Positive Behavior Supports (MBPBS): Effects on Caregivers and Adults with Intellectual and Developmental Disabilities}}. {Front Psychol};2016;7:98.
Caregivers often manage the aggressive behavior of individuals with intellectual and developmental disabilities that reside in community group homes. Sometimes this results in adverse outcomes for both the caregivers and the care recipients. We provided a 7-day intensive Mindfulness-Based Positive Behavior Support (MBPBS) training to caregivers from community group homes and assessed the outcomes in terms of caregiver variables, individuals’ behaviors, and an administrative outcome. When compared to pre-MBPBS training, the MBPBS training resulted in the caregivers using significantly less physical restraints, and staff stress and staff turnover were considerably reduced. The frequency of injury to caregivers and peers caused by the individuals was significantly reduced. A benefit-cost analysis showed substantial financial savings due to staff participation in the MBPBS program. This study provides further proof-of-concept for the effectiveness of MBPBS training for caregivers, and strengthens the call for training staff in mindfulness meditation.
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15. Szatmari P, Chawarska K, Dawson G, Georgiades S, Landa R, Lord C, Messinger DS, Thurm A, Halladay A. {{Prospective Longitudinal Studies of Infant Siblings of Children With Autism: Lessons Learned and Future Directions}}. {J Am Acad Child Adolesc Psychiatry};2016 (Mar);55(3):179-187.
OBJECTIVE: The objectives of this review are to highlight the impact of the first decade of high-risk (HR) infant sibling work in autism spectrum disorder (ASD) and to identify potential areas of translational focus for the next decade of research. METHOD: A group of clinicians and researchers in ASD working both inside and outside of the HR design met on a regular basis to review the infant sibling research, and came to an agreement on areas that had changed clinical practice and areas that had the potential to change practice with further research. The group then outlined several methodological and translational challenges that must be addressed in the next decade of research if the field is to reach its potential. RESULTS: The review concluded that the HR design has yielded an understanding that ASD often, but not always, begins to emerge between 6 and 18 months, with early signs affecting social communication. Research using the HR design has also allowed a better understanding of the sibling recurrence risk (between 10% and 20%). Emerging areas of interest include the developmental trajectories of social communications skills in the early years, the expression of a milder phenotype in siblings not affected with ASD, and the possibility that early intervention with infant siblings may improve outcomes for those with ASD. Important challenges for the future include linking screening to intervention, collecting large sample sizes while ensuring cross-site reliability, and building in capacity for replication. CONCLUSION: Although there are significant methodological and translational challenges for high-risk infant sibling research, the potential of this design to improve long-term outcomes of all children with ASD is substantial.
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16. Turi M, Karaminis T, Pellicano E, Burr D. {{No rapid audiovisual recalibration in adults on the autism spectrum}}. {Sci Rep};2016;6:21756.
Autism spectrum disorders (ASD) are characterized by difficulties in social cognition, but are also associated with atypicalities in sensory and perceptual processing. Several groups have reported that autistic individuals show reduced integration of socially relevant audiovisual signals, which may contribute to the higher-order social and cognitive difficulties observed in autism. Here we use a newly devised technique to study instantaneous adaptation to audiovisual asynchrony in autism. Autistic and typical participants were presented with sequences of brief visual and auditory stimuli, varying in asynchrony over a wide range, from 512 ms auditory-lead to 512 ms auditory-lag, and judged whether they seemed to be synchronous. Typical adults showed strong adaptation effects, with trials proceeded by an auditory-lead needing more auditory-lead to seem simultaneous, and vice versa. However, autistic observers showed little or no adaptation, although their simultaneity curves were as narrow as the typical adults. This result supports recent Bayesian models that predict reduced adaptation effects in autism. As rapid audiovisual recalibration may be fundamental for the optimisation of speech comprehension, recalibration problems could render language processing more difficult in autistic individuals, hindering social communication.
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17. Vogan VM, Morgan BR, Leung RC, Anagnostou E, Doyle-Thomas K, Taylor MJ. {{Widespread White Matter Differences in Children and Adolescents with Autism Spectrum Disorder}}. {J Autism Dev Disord};2016 (Feb 22)
Diffusion tensor imaging studies show white matter (WM) abnormalities in children with autism spectrum disorder (ASD). However, investigations are often limited by small samples, particularly problematic given the heterogeneity of ASD. We explored WM using DTI in a large sample of 130 children and adolescents (7-15 years) with and without ASD, whether age-related changes differed between ASD and control groups, and the relation between DTI measures and ASD symptomatology. Reduced fractional anisotropy and axial diffusivity were observed in ASD in numerous WM tracts, including the corpus callosum and thalamocortical fibres-tracts crucial for interhemispheric connectivity and higher order information processing. Widespread WM compromise in ASD is consistent with the view that ASD is a disorder of generalized complex information processing.
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18. Yang JC, Rodriguez A, Royston A, Niu YQ, Avar M, Brill R, Simon C, Grigsby J, Hagerman RJ, Olichney JM. {{Memantine Improves Attentional Processes in Fragile X-Associated Tremor/Ataxia Syndrome: Electrophysiological Evidence from a Randomized Controlled Trial}}. {Sci Rep};2016;6:21719.
Progressive cognitive deficits are common in patients with fragile X-associated tremor/ataxia syndrome (FXTAS), with no targeted treatment yet established. In this substudy of the first randomized controlled trial for FXTAS, we examined the effects of NMDA antagonist memantine on attention and working memory. Data were analyzed for patients (24 in each arm) who completed both the primary memantine trial and two EEG recordings (at baseline and follow-up) using an auditory « oddball » task. Results demonstrated significantly improved attention/working memory performance after one year only for the memantine group. The event-related potential P2 amplitude elicited by non-targets was significantly enhanced in the treated group, indicating memantine-associated improvement in attentional processes at the stimulus identification/discrimination level. P2 amplitude increase was positively correlated with improvement on the behavioral measure of attention/working memory during target detection. Analysis also revealed that memantine treatment normalized the P2 habituation effect at the follow-up visit. These findings indicate that memantine may benefit attentional processes that represent fundamental components of executive function/dysfunction, thought to comprise the core cognitive deficit in FXTAS. The results provide evidence of target engagement of memantine, as well as therapeutically relevant information that could further the development of specific cognitive or disease-modifying therapies for FXTAS.
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19. Zimmerman DL, Ownsworth T, O’Donovan A, Roberts J, Gullo MJ. {{Independence of Hot and Cold Executive Function Deficits in High-Functioning Adults with Autism Spectrum Disorder}}. {Front Hum Neurosci};2016;10:24.
Individuals with autistic spectrum disorder (ASD) display diverse deficits in social, cognitive and behavioral functioning. To date, there has been mixed findings on the profile of executive function deficits for high-functioning adults (IQ > 70) with ASD. A conceptual distinction is commonly made between « cold » and « hot » executive functions. Cold executive functions refer to mechanistic higher-order cognitive operations (e.g., working memory), whereas hot executive functions entail cognitive abilities supported by emotional awareness and social perception (e.g., social cognition). This study aimed to determine the independence of deficits in hot and cold executive functions for high-functioning adults with ASD. Forty-two adults with ASD (64% male, aged 18-66 years) and 40 age and gender matched controls were administered The Awareness of Social Inference Test (TASIT; emotion recognition and social inference), Letter Number Sequencing (working memory) and Hayling Sentence Completion Test (response initiation and suppression). Between-group analyses identified that the ASD group performed significantly worse than matched controls on all measures of cold and hot executive functions (d = 0.54 – 1.5). Hierarchical multiple regression analyses revealed that the ASD sample performed more poorly on emotion recognition and social inference tasks than matched controls after controlling for cold executive functions and employment status. The findings also indicated that the ability to recognize emotions and make social inferences was supported by working memory and response initiation and suppression processes. Overall, this study supports the distinction between hot and cold executive function impairments for adults with ASD. Moreover, it advances understanding of higher-order impairments underlying social interaction difficulties for this population which, in turn, may assist with diagnosis and inform intervention programs.
