1. Bast N, Poustka L, Freitag CM. {{The locus coeruleus – norepinephrine system as pacemaker of attention -A developmental mechanism of derailed attentional function in autism spectrum disorder}}. {Eur J Neurosci};2017 (Dec 15)
Children with autism spectrum disorder (ASD) exhibit diminished visual engagement to environmental stimuli. Aberrant attentional function provides an explanation by reduced phasic alerting and orienting to exogenous stimuli. We review aberrant attentional function (alerting, orienting, and attentional control) in children with ASD as studied by neurocognitive and neurophysiological tasks as well as magnetic resonance imaging studies. The locus coeruleus – norepinephrine (LC-NE) system is outlined as a pacemaker of attentional function. The LC-NE system regulates adaptive gain in synaptic signal transmission, which moderates phasic alerting (‘promoting’) and the activation of the ventral frontoparietal attention network within orienting (‘permitting’). In children with ASD, atypical LC-NE activity is proposed as underlying mechanism of aberrant attentional function. It may manifest as a) increased tonic activity with reduced phasic reactivity to exogenous stimuli, b) attenuated bottom-up signaling mitigating salience and predictive reward attribution during phasic alerting, and c) reduced activation of the ventral frontoparietal attention system attenuating orienting to exogenous stimuli. Increased tonic pupil dilation and aberrant pupil reactivity are discussed as indicators of atypical LC-NE activity. Pupillometry is outlined as feasible method to assess alerting, orienting, and attentional control that can be dissected from the pupil dilation time course. In children with ASD, aberrant attentional function through atypical LC-NE activity is proposed as developmental mechanism leading to reduced social attention as well as social interaction and communication impairments. This article is protected by copyright. All rights reserved.
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2. Paula CS, Cunha GR, Bordini D, Brunoni D, Moya AC, Bosa CA, Mari JJ, Cogo-Moreira H. {{Identifying Autism with a Brief and Low-Cost Screening Instrument-OERA: Construct Validity, Invariance Testing, and Agreement Between Judges}}. {J Autism Dev Disord};2017 (Dec 15)
Simple and low-cost observational-tools to detect symptoms of Autism Spectrum Disorder (ASD) are still necessary. The OERA is a new assessment tool to screen children eliciting observable behaviors with no substantial knowledge on ASD required. The sample was 99 children aged 3-10: 76 with ASD and 23 without ASD (11/23 had intellectual disability). The 13 remained items exhibited high interrater agreement and high reliability loaded onto a single latent trait. Such model showed excellent fit indices evaluated via confirmatory factor analysis and no item showed differential function in terms of age/sex/IQ. A cutoff of five points or higher resulted in the highest sensitivity (92.75) and specificity (90.91) percentages. OERA is a brief, stable, low-cost standardized observational-screening to identify ASD children.
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3. Wadsworth HM, Maximo JO, Donnelly RJ, Kana RK. {{Action simulation and mirroring in children with autism spectrum disorders}}. {Behav Brain Res};2017 (Dec 13);341:1-8.
Mental imitation, perhaps a precursor to motor imitation, involves visual perspective-taking and motor imagery. Research on mental imitation in autism spectrum disorders (ASD) has been rather limited compared to that on motor imitation. The main objective of this fMRI study is to determine the differences in brain responses underlying mirroring and mentalizing networks during mental imitation in children and adolescents with ASD. Thirteen high-functioning children and adolescents with ASD and 15 age-and- IQ-matched typically developing (TD) control participants took part in this fMRI study. In the MRI scanner, participants were shown cartoon pictures of people performing everyday actions (Transitive actions: e.g., ironing clothes but with the hand missing; and Intransitive actions: e.g., clapping hands with the palms missing) and were asked to identify which hand or palm orientation would best fit the gap. The main findings are: 1) both groups performed equally while processing transitive and intransitive actions; 2) both tasks yielded activation in the bilateral inferior frontal gyrus (IFG) and inferior parietal lobule (IPL) in ASD and TD groups; 3) Increased activation was seen in ASD children, relative to TD, in left ventral premotor and right middle temporal gyrus during intransitive actions; and 4) ASD symptom severity positively correlated with activation in left parietal, right middle temporal, and right premotor regions across all subjects. Overall, our findings suggest that regions mediating mirroring may be recruiting more brain resources in ASD and may have implications for understanding social movement through modeling.
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4. Weeke LC, Groenendaal F, Mudigonda K, Blennow M, Lequin MH, Meiners LC, van Haastert IC, Benders MJ, Hallberg B, de Vries LS. {{A Novel Magnetic Resonance Imaging Score Predicts Neurodevelopmental Outcome After Perinatal Asphyxia and Therapeutic Hypothermia}}. {J Pediatr};2018 (Jan);192:33-40.e32.
OBJECTIVE: To assess the predictive value of a novel magnetic resonance imaging (MRI) score, which includes diffusion-weighted imaging as well as assessment of the deep grey matter, white matter, and cerebellum, for neurodevelopmental outcome at 2 years and school age among term infants with hypoxic-ischemic encephalopathy treated with therapeutic hypothermia. STUDY DESIGN: This retrospective cohort study (cohort 1, The Netherlands 2008-2014; cohort 2, Sweden 2007-2012) including infants born at >36 weeks of gestational age treated with therapeutic hypothermia who had an MRI in the first weeks of life. The MRI score consisted of 3 subscores: deep grey matter, white matter/cortex, and cerebellum. Primary adverse outcome was defined as death, cerebral palsy, Bayley Scales of Infant and Toddler Development, third edition, motor or cognitive composite scores at 2 years of <85, or IQ at school age of <85. RESULTS: In cohort 1 (n = 97) and cohort 2 (n = 76) the grey matter subscore was an independent predictor of adverse outcome at 2 years (cohort 1, OR, 1.6; 95% CI, 1.3-1.9; cohort 2, OR, 1.4; 95% CI, 1.2-1.6), and school age (cohort 1, OR, 1.3; 95% CI, 1.2-1.5; cohort 2, OR, 1.3; 95% CI, 1.1-1.6). The white matter and cerebellum subscore did not add to the predictive value. The positive predictive value, negative predictive value, and area under the curve for the grey matter subscore were all >0.83 in both cohorts, whereas the specificity was >0.91 with variable sensitivity. CONCLUSION: A novel MRI score, which includes diffusion-weighted imaging and assesses all brain areas of importance in infants with therapeutic hypothermia after perinatal asphyxia, has predictive value for outcome at 2 years of age and at school age, for which the grey matter subscore can be used independently.
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5. Tan CD. {{« I’m a normal autistic person, not an abnormal neurotypical »: Autism Spectrum Disorder diagnosis as biographical illumination}}. {Soc Sci Med};2017 (Dec 9);197:161-167.
Building on Michael Bury’s « biographical disruption » and Kathy Charmaz’s « loss of self, » which describe the deteriorative impacts of chronic illness on perceptions of selfhood, I propose « biographical illumination »-a transformed conceptualization of self and identity that is facilitated by but extends beyond medical meaning, enriching personal biography and social relationships. The concept is perhaps most applicable to experiences with neurological and neurodevelopmental conditions in which brain difference and personhood are perceived to be closely intertwined. In this study, biographical illumination is used to describe the experiences of autistic adults who learned of their Autism Spectrum Disorder (ASD) diagnosis during teen years or adulthood. Through an ASD lens, participants found explanation for their atypicality and developed a more valued self-concept. Learning of the condition did not disrupt their biography; rather, it became integral to and constitutive of it. With a new self-concept, participants re-gauged personal expectations for normalization and accessed communities of alike others, forging relationships that affirmed identity.
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6. Marland C, Lichtenstein P, Degl’Innocenti A, Larson T, Rastam M, Anckarsater H, Gillberg C, Nilsson T, Lundstrom S. {{The Autism-Tics, ADHD and other Comorbidities inventory (A-TAC): previous and predictive validity}}. {BMC Psychiatry};2017 (Dec 16);17(1):403.
BACKGROUND: Reliable and easy to administer screening instruments focusing on neurodevelopmental disorders and associated conditions are scarce. The Autism-Tics, AD/HD and other Comorbidities inventory (A-TAC) has previously been validated and reporting good- excellent validity for several disorders. This article aims to expand these findings by including more conditions in a substantially larger sample augmented with the Swedish National Patient Register (NPR). METHODS: Since 2004 parents of all 9-year-old Swedish twins have been invited to participate in a telephone interview in the Child and Adolescent Twin Study in Sweden, CATSS. The CATSS is linked to the NPR which includes data from in- and outpatient care. Data on neurodevelopmental disorders (A-TAC) collected in CATSS were compared with diagnoses from the NPR. We investigated diagnoses that had been made both before (previous validity) and after (predictive validity) the interview. RESULTS: Sensitivity and specificity of A-TAC scores for predicting earlier or later clinical diagnoses were mostly good-excellent, with values of the area under the curve for a clinical diagnosis of autism spectrum disorder (ASD) of .98, attention deficit hyperactivity disorder (ADHD) .93, learning disorder (LD) .92, and oppositional defiant disorder (ODD) .99, with small differences in terms of previous and predictive analyses. A-TAC provided little validity for eating disorders. CONCLUSION: The result support previous claims: A-TAC is a broad screening instrument with a particular strength in assessing ASD, ADHD, LD, and ODD at ages 9 and 12, and also provides phenotypic information about other child psychiatric disorders.
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7. Wei Y, Silke JR, Xia X. {{Elucidating the 16S rRNA 3′ boundaries and defining optimal SD/aSD pairing in Escherichia coli and Bacillus subtilis using RNA-Seq data}}. {Sci Rep};2017 (Dec 15);7(1):17639.
Bacterial translation initiation is influenced by base pairing between the Shine-Dalgarno (SD) sequence in the 5′ UTR of mRNA and the anti-SD (aSD) sequence at the free 3′ end of the 16S rRNA (3′ TAIL) due to: 1) the SD/aSD sequence binding location and 2) SD/aSD binding affinity. In order to understand what makes an SD/aSD interaction optimal, we must define: 1) terminus of the 3′ TAIL and 2) extent of the core aSD sequence within the 3′ TAIL. Our approach to characterize these components in Escherichia coli and Bacillus subtilis involves 1) mapping the 3′ boundary of the mature 16S rRNA using high-throughput RNA sequencing (RNA-Seq), and 2) identifying the segment within the 3′ TAIL that is strongly preferred in SD/aSD pairing. Using RNA-Seq data, we resolve previous discrepancies in the reported 3′ TAIL in B. subtilis and recovered the established 3′ TAIL in E. coli. Furthermore, we extend previous studies to suggest that both highly and lowly expressed genes favor SD sequences with intermediate binding affinity, but this trend is exclusive to SD sequences that complement the core aSD sequences defined herein.
