1. Apicella F, Sicca F, Federico RR, Campatelli G, Muratori F. {{Fusiform Gyrus responses to neutral and emotional faces in children with Autism Spectrum Disorders: a High Density ERP study}}. {Behav Brain Res};2012 (Oct 31)
Face processing is a neural mechanism that allows understanding social information and cues conveyed by faces, whose dysfunction has been postulated to underlie some of the behavioral impairments characterizing Autism Spectrum Disorders (ASD). A special region of the cortex, the Fusiform Gyrus (FG), is believed to be the specific area for processing face features and emotions. However, behavioral, fMRI and ERP studies addressed to investigate the role of FG dysfunction in ASD have led to conflicting results. Using a high-density EEG system, we recorded the face-sensitive ERP to neutral and emotional (happiness and fearful) faces, as a measure of early activity of the FG, in children with high functioning ASD. By controlling a number of experimental and clinical variables that could have biased previous research – such as gaze direction, attention to tasks, stimulus appearance and clinical profiles – we aimed to assess the effective role of the FG in the face emotion processing deficit hypothesized in ASD. No significant differences in early face-sensitive ERP components were found between ASD and neurotypical children. However, a systematic latency delay and amplitude reduction of all early potentials were observed in the ASD group, regardless of the stimulus, although more evident for emotions. Therefore, we can assume a diffuse dysfunction of neural mechanisms and networks in driving and integrating social information conveyed by faces, in particular when emotions are involved, rather than a specific impairment of the FG-related face processing circuit. Nevertheless, there is need of further investigation.
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2. Baron-Cohen S. {{Autism and the technical mind: children of scientists and engineers may inherit genes that not only confer intellectual talents but also predispose them to autism}}. {Sci Am};2012 (Nov);307(5):72-75.
3. Brock J. {{Alternative Bayesian accounts of autistic perception: comment on Pellicano and Burr}}. {Trends Cogn Sci};2012 (Nov 1)
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4. Derecki NC, Cronk JC, Kipnis J. {{The role of microglia in brain maintenance: implications for Rett syndrome}}. {Trends Immunol};2012 (Oct 30)
The role of microglia in central nervous system (CNS) pathology has been studied extensively, and more recently, examination of microglia in the healthy brain has yielded important insights into their many functions. It was long assumed that microglia were essentially quiescent cells, unless provoked into activation, which was considered a hallmark of disease. More recently, however, it has become increasingly clear that they are extraordinarily dynamic cells, constantly sampling their environment and adjusting to exquisitely delicate stimuli. Along these lines, our laboratory has identified a new and unexpected role for microglial phagocytosis – or lack thereof – in the pathophysiology of Rett syndrome, a neurodevelopmental disease caused by mutation of the gene encoding methyl-CpG binding protein (MECP)2. We have shown that specific expression of wild type Mecp2 in myeloid cells of Mecp2-null mice is sufficient to arrest major symptoms associated with this devastating disease. This beneficial effect, however, is abolished if phagocytic activity of microglia is inhibited. Here, we discuss microglial origins, the role of microglia in brain development and maintenance, and the phenomenon of microglial augmentation by myeloid progenitor cells in the adult brain. Finally, we address in some detail the beneficial roles of microglia as clinical targets in Rett syndrome and other neurological disorders.
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5. Doherty-Sneddon G, Whittle L, Riby DM. {{Gaze aversion during social style interactions in autism spectrum disorder and Williams syndrome}}. {Res Dev Disabil};2012 (Oct 31);34(1):616-626.
During face-to-face interactions typically developing individuals use gaze aversion (GA), away from their questioner, when thinking. GA is also used when individuals with autism (ASD) and Williams syndrome (WS) are thinking during question-answer interactions. We investigated GA strategies during face-to-face social style interactions with familiar and unfamiliar interlocutors. Participants with WS and ASD used overall typical amounts/patterns of GA with all participants looking away most while thinking and remembering (in contrast to listening and speaking). However there were a couple of specific disorder related differences: participants with WS looked away less when thinking and interacting with unfamiliar interlocutors; in typical development and WS familiarity was associated with reduced gaze aversion, however no such difference was evident in ASD. Results inform typical/atypical social and cognitive phenotypes. We conclude that gaze aversion serves some common functions in typical and atypical development in terms of managing the cognitive and social load of interactions. There are some specific idiosyncracies associated with managing familiarity in ASD and WS with elevated sociability with unfamiliar others in WS and a lack of differentiation to interlocutor familiarity in ASD. Regardless of the familiarity of the interlocutor, GA is associated with thinking for typically developing as well as atypically developing groups. Social skills training must take this into account.
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6. Gadow KD, Devincent CJ, Siegal VI, Olvet DM, Kibria S, Kirsch SF, Hatchwell E. {{Allele-Specific Associations of 5-HTTLPR/rs25531 with ADHD and Autism Spectrum Disorder}}. {Prog Neuropsychopharmacol Biol Psychiatry};2012 (Oct 31)
BACKGROUND: The aims of the present study were to examine the association between a common serotonin transporter gene (SLC6A4) polymorphism 5-HTTLPR/rs25531 with severity of attention-deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) symptoms. METHODS: Mothers and teachers completed a validated DSM-IV-referenced rating scale for ADHD and ASD symptoms in 118 children with ASD. RESULTS: Analyses indicated that children with at least one copy of the S or L(G) allele obtained significantly more severe maternal ratings of hyperactivity (p=0.001; etap(2)=0.097) and impulsivity (p=0.027; etap(2)=0.044) but not inattention (p=0.061; etap(2)=0.032), controlling for ASD severity, than children homozygous for the L(A) allele. Conversely, mothers’ ratings indicated that children with L(A)/L(A) genotype had more severe ASD social deficits than S+or L(G) allele carriers (p=0.003; etap(2)=0.081), controlling for ADHD symptom severity. Teachers’ ratings though consistent with mothers’ ratings of hyperactivity and social deficits were marginally significant (p=0.07/p=0.09). There was some evidence that the magnitude of parent-teacher agreement regarding symptom severity varied as a function of the child’s genotype. CONCLUSION: The 5-HTTLPR/rs25531 polymorphism or its correlates may modulate severity of ADHD and ASD symptoms in children with ASD, but in different ways. These tentative, hypothesis-generating findings require replication with larger independent samples.
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7. Hamlyn J, Duhig M, McGrath J, Scott J. {{Modifiable risk factors for schizophrenia and autism – shared risk factors impacting on brain development}}. {Neurobiol Dis};2012 (Nov 1)
Schizophrenia and autism are two poorly understood clinical syndromes that differ in age of onset and clinical profile. However, recent genetic and epidemiological research suggests that these two neurodevelopmental disorders share certain risk factors. The aims of this review are to describe modifiable risk factors that have been identified in both disorders, and, where available, collate salient systematic reviews and meta-analyses that have examined shared risk factors. Based on searches of Medline, Embase and Psychoinfo, inspection of review articles and expert opinion, we first compiled a set of candidate modifiable risk factors associated with autism. Where available, we next collated systematic-reviews (with or without meta-analyses) related to modifiable risk factors associated with both autism and schizophrenia. We identified three modifiable risk factors that have been examined in systematic reviews for both autism and schizophrenia. Advanced paternal age was reported as a risk factor for schizophrenia in a single meta-analysis and as a risk factor in two meta-analyses for autism With respect to pregnancy and birth complications, for autism one meta-analysis identified maternal diabetes and bleeding during pregnancy as risks factors for autism whilst a meta-analysis of eight studies identified obstetric complications as a risk factor for schizophrenia . Migrant status was identified as a risk factor for both autism and schizophrenia. Two separate meta-analyses were identified for each disorder. Despite distinct clinical phenotypes, the evidence suggests that at least some non-genetic risk factors are shared between these two syndromes. In particular, exposure to drugs, nutritional excesses or deficiencies and infectious agents lend themselves public health interventions. Studies are now needed to quantify any increase in risk of either autism or schizophrenia that is associated with these modifiable environmental factors.
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8. Hoffmann W, Konig U, Heinzel-Gutenbrunner M, Mattejat F, Becker K, Kamp-Becker I. {{Early identification of Asperger syndrome in young children}}. {Res Dev Disabil};2012 (Oct 30);34(1):640-649.
This study was designed to identify items of the ADI-R that allow an early and sensitive identification of children with possible Asperger syndrome (AS). The aim was to obtain an economic short interview suitable for screening purposes. The study was based on data from a clinical sample of 5-18-year-old children and adolescents (mean age 10.9years) with either Attention-Deficit Hyperactivity Disorder (ADHD; n=43) or AS (n=62). The introductory questions and 36 items, which contribute to the diagnostic algorithm of the ADI-R, were subjected to content analysis and stepwise discriminant function analysis. Eight meaningful items were found, which were shown to be good predictors of AS and to discriminate between the children with AS and those with ADHD. The short interview was especially useful for the assessment and screening of children up to 11years in our sample, because in this subgroup, sensitivity was even higher (.92) and specificity was also excellent (.90). Eight items with high discriminatory power allowed sensitive and economic screening for young children with suspected AS.
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9. Kanemura H, Sano F, Tando T, Sugita K, Aihara M. {{Can EEG characteristics predict development of epilepsy in autistic children?}}. {Eur J Paediatr Neurol};2012 (Oct 30)
BACKGROUND: The high occurrence of epilepsy in children with autism spectrum disorders (ASD) is a clear indication that ASD has a neurobiological basis. The current understanding of the association between epilepsy and ASD is still limited, but from a clinical point of view, this association should not be overlooked. AIMS: We investigated the electroencephalogram (EEG) paroxysmal abnormality in children with ASD and the incidence of later development of epilepsy. METHODS: Participants were recruited from University of Yamanashi hospital and 5 satellite hospitals between April 1, 2001 and March 31, 2005. EEG recordings and clinical evaluations were performed every 6 months for at least 6 years, focusing on paroxysmal abnormality. We scored the occurrence and the location of spikes and evaluated the relation with later development of epilepsy. RESULTS: The prospective study included 21 patients with ASD (12 males and 9 females) between the ages of 3 and 6 years. EEG paroxysmal abnormalities were present in 11/21 patients (52.4%). In addition, six of 21 patients (28.6%) had epilepsy at some point in their lives. The presence of frontal paroxysms was significantly associated with later development of epilepsy compared with centrotemporal paroxysmus (p < 0.003). The type of seizure diagnosed was mainly partial; in particular, partial with secondary generalization in 4/6 (66.7%). CONCLUSION: The presence of frontal paroxysms may indicate a higher risk of epilepsy in ASD.
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10. Katsnelson A. {{The autism pill}}. {Sci Am};2012 (Nov);307(5):16.
11. Matson JL, Dempsey T, Lovullo SV, Fodstad JC, Knight C, Sevin JA, Sharp B. {{The moderating effects of intellectual development on core symptoms of autism and PDD-NOS in toddlers and infants}}. {Res Dev Disabil};2012 (Oct 30);34(1):573-578.
Little research has been conducted on whether deficits in developmental functioning affect the range of core symptoms for autism spectrum disorders (ASD). This study represents a first attempt to determine whether developmental level has an effect on the expression of ASD symptoms in infants and toddlers. Eight hundred and fifty-three infants were evaluated with respect to the nature and extent of their ASD symptoms and developmental functioning. Young children with autism displayed a higher number of symptoms than those with PDD-NOS on all three domains of impairment (social, communication, repetitive behaviors). As expected, children without an ASD evinced far fewer symptoms than both these groups. Developmental level was not found to be a moderator for expression of ASD symptoms for the entire sample, or individual diagnostic groups. Higher developmental level was associated with lower severity of evinced ASD symptoms in the sample.
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12. Murphy D, Spooren W. {{EU-AIMS: a boost to autism research}}. {Nat Rev Drug Discov};2012 (Nov);11(11):815-816.
A [euro]30 million initiative bringing together academic centres, industry, charities and patient groups provides an unprecedented opportunity for translational research on autism.
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13. Neumeyer AM, Gates A, Ferrone C, Lee H, Misra M. {{Bone Density in Peripubertal Boys with Autism Spectrum Disorders}}. {J Autism Dev Disord};2012 (Nov 4)
We determined whether bone mineral density (BMD) is lower in boys with autism spectrum disorders (ASD) than controls, and also assessed variables that may affect BMD in ASD. BMD was measured using dual energy X-ray absorptiometry (DXA) in 18 boys with ASD and 19 controls 8-14 years old. Boys with ASD had lower BMD Z-scores at the spine, hip and femoral neck, and differences at the hip and femoral neck persisted after controlling for maturity and BMI. Vitamin D intake from food and in serum were lower in ASD subjects, as was exercise activity. We conclude that BMD is lower in peripubertal boys with ASD and may be associated with impaired vitamin D status and lower exercise activity.
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14. O’Haire ME. {{Animal-Assisted Intervention for Autism Spectrum Disorder: A Systematic Literature Review}}. {J Autism Dev Disord};2012 (Nov 5)
The inclusion of animals in therapeutic activities, known as animal-assisted intervention (AAI), has been suggested as a treatment practice for autism spectrum disorder (ASD). This paper presents a systematic review of the empirical research on AAI for ASD. Fourteen studies published in peer-reviewed journals qualified for inclusion. The presentation of AAI was highly variable across the studies. Reported outcomes included improvements for multiple areas of functioning known to be impaired in ASD, namely increased social interaction and communication as well as decreased problem behaviors, autistic severity, and stress. Yet despite unanimously positive outcomes, most studies were limited by many methodological weaknesses. This review demonstrates that there is preliminary « proof of concept » of AAI for ASD and highlights the need for further, more rigorous research.
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15. Osterweil EK, Kind PC, Bear MF. {{Lifting the mood on treating fragile x}}. {Biol Psychiatry};2012 (Dec 1);72(11):895-897.
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16. Reith RM, McKenna J, Wu H, Hashmi SS, Cho SH, Dash PK, Gambello MJ. {{Loss of Tsc2 in Purkinje cells is associated with autistic-like behavior in a mouse model of tuberous sclerosis complex}}. {Neurobiol Dis};2012 (Nov 1)
Tuberous sclerosis complex (TSC) is a dominant tumor suppressor disorder caused by mutations in either TSC1 or TSC2. TSC causes substantial neuropathology, often leading to autism spectrum disorders (ASDs) in up to 60% of patients. The anatomic and neurophysiologic links between these two disorders are not well understood. We have generated and characterized a novel TSC mouse model with Purkinje cell specific Tsc2 loss. These Tsc2f/-;Cre mice exhibit progressive Purkinje cell degeneration. Since loss of Purkinje cells is a well reported postmortem finding in patients with ASD, we conducted a series of behavior tests to asses if Tsc2f/-;Cre mice displayed autistic-like deficits. Tsc2f/-;Cre mice demonstrated increased repetitive behavior as assessed with marble burying activity. Using the three chambered apparatus to asses social behavior, we found that Tsc2f/-;Cre mice showed behavioral deficits, exhibiting no preference between a stranger mouse and an inanimate object, or between a novel and a familiar mouse. We also detected social deficits in Tsc2f/f;Cre mice, suggesting Purkinje cell pathology is sufficient to induce ASD-like behavior. Importantly, social behavior deficits were prevented with rapamycin treatment. Altogether, these results demonstrate that loss of Tsc2 in Purkinje cells in a Tsc2-haploinsufficient background lead to autistic-like behavioral deficits. These studies provide compelling evidence that Purkinje cell loss and/or dysfunction may be an important link between TSC and ASD as well as a general anatomic phenomenon that contributes to the ASD phenotype.
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17. Richmond LL, Thorpe M, Berryhill ME, Klugman J, Olson IR. {{Individual differences in autistic trait load in the general population predict visual working memory performance}}. {Q J Exp Psychol (Hove)};2012 (Nov 5)
Prior studies have reported instances of both intact and impaired working memory (WM) performance in people with autism spectrum disorder (ASD). In order to investigate the relation between autistic traits that extend into the normal population and WM, 104 normal college-aged students who varied in their levels of autistic traits were tested. The loading of ASD-associated traits in the normal population leads to differing predictions about WM performance. ASD traits related to a local processing style (or « attention to detail ») might enhance WM while ASD-associated traits related to difficulty switching attention and reorienting focus (or « social interaction ») might impair WM performance. To assess these predictions, participants filled out the Autism Spectrum Quotient (AQ) and performed a working memory task with both visual and verbal variants. AQ scores were then broken into « attention to detail » and « social interaction » factors, as proposed by Hoekstra and colleagues. The results showed that AQ scores did not predict verbal WM performance but they did predict visual WM performance. The social interaction and attention to detail factors of the AQ had opposing relationships with visual WM performance: A higher level of social difficulty was associated with significantly poorer visual WM performance while a higher level of attention to detail was associated with enhanced visual WM performance. Further investigation of the relation between AQ and WM using the original five-factor model proposed by Baron-Cohen and colleagues (2001) revealed an association between impoverished imagination and visual WM overall.
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18. Rombough A, Iarocci G. {{Orienting in Response to Gaze and the Social Use of Gaze among Children with Autism Spectrum Disorder}}. {J Autism Dev Disord};2012 (Nov 3)
Potential relations between gaze cueing, social use of gaze, and ability to follow line of sight were examined in children with autism and typically developing peers. Children with autism (mean age = 10 years) demonstrated intact gaze cueing. However, they preferred to follow arrows instead of eyes to infer mental state, and showed decreased accuracy in following line of sight when several visual distracters were present. Performance across tasks was not correlated for either group. Findings suggest that children with autism are less inclined to prioritize and select eyes, particularly in visually-rich environments. Gaze-following deficits may lie at the level of selective attention, rather than cueing-a possibility that can be explored with more complex and ecologically valid tasks.
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19. Schafer EC, Mathews L, Mehta S, Hill M, Munoz A, Bishop R, Moloney M. {{Personal FM systems for children with autism spectrum disorders (ASD) and/or attention-deficit hyperactivity disorder (ADHD): An initial investigation}}. {J Commun Disord};2012 (Oct 16)
The goal of this initial investigation was to examine the potential benefit of a frequency modulation (FM) system for 11 children diagnosed with autism spectrum disorders (ASD), attention-deficit hyperactivity disorder (ADHD), or both disorders through measures of speech recognition performance in noise, observed classroom behavior, and teacher-rated educational risk and listening behaviors. Use of the FM system resulted in significant average improvements in speech recognition in noise for the children with ASD and ADHD as well as large effect sizes. When compared to typically functioning peers, children with ASD and ADHD had significantly poorer average speech recognition performance in noise without the FM system but comparable average performance when the FM system was used. Similarly, classroom observations yielded a significant increase in on-task behaviors and large effect sizes when the FM system was in use during two separate trial periods. Although teacher ratings on questionnaires showed no significant improvement in the average level of educational risk of participants, they did indicate significant improvement in average listening behaviors during two trial periods with the FM system. Given the significantly better speech recognition in noise, increased on-task behaviors, and improved teacher ratings of listening behaviors with the FM system, these devices may be a viable option for children who have ASD and ADHD in the classroom. However, an individual evaluation including audiological testing and a functional evaluation in the child’s primary learning environment will be necessary to determine the benefit of an FM system for a particular student. Learning Outcomes: 1. The reader will be able to describe the potential benefit of FM systems for children with ASD and/or ADHD. 2. The reader will be able to identify on-task versus off-task listening behaviors in children with ASD and/or ADHD. 3. The reader will be able to explain the components of a successful pre-fit education program that may be necessary prior to fitting an FM system in children with ASD.
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20. Seymour M, Wood C, Giallo R, Jellett R. {{Fatigue, Stress and Coping in Mothers of Children with an Autism Spectrum Disorder}}. {J Autism Dev Disord};2012 (Nov 3)
Raising a child with an autism spectrum disorder (ASD) can be exhausting, which has the potential to impact on parental health and wellbeing. The current study investigated the influence of maternal fatigue and coping on the relationship between children’s problematic behaviours and maternal stress for 65 mothers of young children (aged 2-5 years) with ASDs. Results showed that maternal fatigue but not maladaptive coping mediated the relationship between problematic child behaviours and maternal stress. These findings suggest child behaviour difficulties may contribute to parental fatigue, which in turn may influence use of ineffective coping strategies and increased stress. The significance of fatigue on maternal wellbeing was highlighted as an important area for consideration in families of children with an ASD.
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21. Strid K, Heimann M, Tjus T. {{Pretend play, deferred imitation and parent-child interaction in speaking and non-speaking children with autism}}. {Scand J Psychol};2012 (Nov 2)
Strid, K., Heimann, M. & Tjus T. (2012). Pretend play, deferred imitation and parent-child interaction in speaking and non-speaking children with autism. Scandinavian Journal of Psychology. This study investigates spontaneous pretend play during a parent-child free play observation, and deferred imitation observed in an experimental setting in speaking and non-speaking children with autism in comparison to children with typical development. Both groups of children with autism showed a reduced level of deferred imitation compared to the typically developing group, but only the non-speaking children with autism spent significantly less time in pretend play compared to children with typical development. Deferred imitation was related to parents’ verbal interaction in both groups. An analysis of the parent-child interaction revealed that parents of children with autism used less synchronized comments compared to parents of typically developing children. Parents of the speaking group with autism used more synchronized than unsynchronized comments, while parents of the non-speaking group used the same amount of synchronized and unsynchronized comments. These findings are discussed in terms of how the developmental level affects behavior and interaction in autism.
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22. Swettenham J, Remington A, Laing K, Fletcher R, Coleman M, Gomez JC. {{Perception of Pointing from Biological Motion Point-Light Displays in Typically Developing Children and Children with Autism Spectrum Disorder}}. {J Autism Dev Disord};2012 (Nov 3)
We examined whether the movement involved in a pointing gesture, depicted using point-light displays, is sufficient to cue attention in typically developing children (TD) and children with autism spectrum disorder (ASD) (aged 8-11 years). Using a Posner-type paradigm, a centrally located display indicated the location of a forthcoming target on 80 % of trials and the opposite location on 20 % of trials. TD children, but not children with ASD, were faster to identify a validly cued target than an invalidly cued target. A scrambled version of the point-light pointing gesture, retaining individual dot speed and direction of movement but not the configuration, produced no validity effect in either group. A video of a pointing gesture produced validity effects in both groups.
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23. Vanvuchelen M, Van Schuerbeeck L, Roeyers H, De Weerdt W. {{Understanding the mechanisms behind deficits in imitation: Do individuals with autism know ‘what’ to imitate and do they know ‘how’ to imitate?}}. {Res Dev Disabil};2012 (Oct 31);34(1):538-545.
Although imitation problems have been associated with autism for many years, the underlying mechanisms of these problems remain subject to debate. In this article, the question whether imitation problems are caused by selection or correspondence problems is explored and discussed. This review revealed that hypotheses on the nature of imitation problems in autism are complicated and inconclusive at the present time. There is some evidence for impaired selection, especially implicating poor preferential attention to biological motion and poor ascription of intention to action. There is also some evidence that both transformations of perspectives and mapping of visual to motor information are impaired, characterized as correspondence problems. However, it is not yet clear how poor selection processes contribute to correspondence problems and vice versa. Insight in this interaction may provide a valuable contribution to our understanding of imitation problems in autism. For further research we recommend that tasks should be constrained to target as few mechanisms as possible in given experiments.
