1. Bolte S, Duketis E, Poustka F, Holtmann M. {{Sex differences in cognitive domains and their clinical correlates in higher-functioning autism spectrum disorders}}. {Autism};2011 (Mar 31)
Despite the skewed sex ratio, few studies have addressed possible cognitive sex differences in autism spectrum disorders (ASDs). This study compared visual attention to detail (ATTD) and selected executive functions (EF) in 35 males and 21 females with higher-functioning ASD and unaffected sibling controls. Females with ASD outperformed males on EF as assessed by the Trail Making Test B-A. Males with ASD showed superior performance for ATTD as measured by the Block Design Test (BD) when compared with females. EF difficulties in males were correlated with more stereotypic behaviours and interests on the Autism Diagnostic Interview-Revised or the Autism Diagnostic Observation Schedule. The results indicated clinically meaningful cognitive sex differences in ASD, particularly an association between EF and stereotypic behaviours and interests. ATTD as a potential basis for specific cognitive strengths (e.g. scientific/savant skills) might be more pronounced in males with ASD.
2. Humphrey N, Symes W. {{Peer interaction patterns among adolescents with autistic spectrum disorders (ASDs) in mainstream school settings}}. {Autism};2011 (Mar 31)
The aim of the current study was to document the peer interaction patterns of students with autistic spectrum disorders in mainstream settings. Structured observations of a group of 38 adolescents with ASD drawn from 12 mainstream secondary schools were conducted over a two-day period and data compared with those of school, age, and gender matched comparison groups of 35 adolescents with dyslexia and 38 with no identified special educational needs (the ASD and dyslexia groups were also matched on SEN provision). Frequency and duration of peer interaction behaviours were coded. In terms of duration, multivariate analyses of variance (MANOVAs) indicated that participants with ASD spent more time engaged in solitary behaviours, less time engaged in co-operative interaction with peers, and more time engaging in reactive aggression towards peers than either comparison group. In terms of frequency, similar patterns emerged, but additionally participants with ASD engaged in fewer instances of rough/vigorous play, and were subject to more instances of social initiation and instrumental verbal aggression by peers than either comparison group. The findings of the current study support the authors’ theoretical model of peer group interaction processes for individuals with ASD, and have implications for both social skills training and the development of peer awareness and sensitivity. Limitations are noted.
3. Lecavalier L, Gadow KD, Devincent CJ, Houts CR, Edwards MC. {{Validity of DSM-IV syndromes in preschoolers with autism spectrum disorders}}. {Autism};2011 (Mar 31)
Behavior and emotional problems are often present in very young children with autism spectrum disorders (ASDs) but their nosology has been the object of scant empirical attention. The objective of this study was to assess the construct validity of select Diagnostic and Statistical Manual of Mental Disorders (DSM)-defined syndromes (ADHD, ODD, Mood disorder) in preschoolers with ASD (N = 229). Parents and teachers completed the Early Childhood Inventory-4, a behavior rating scale based on the DSM-IV, and ratings were submitted to confirmatory factor analysis. Results generally supported the DSM nosology in this population. There was some evidence that parent ratings were associated with better fit indices (e.g. RSMEA = .062) than teachers (e.g. RMSEA = .083). For both raters, fit indices appeared to improve when the ADHD factor was broken into its constituent parts. However, hyperactivity symptoms accounted for little unique additional variance in the model. Findings lend support to the DSM as a conceptual model for behavioral syndromes in preschoolers with ASDs and also reinforce the importance of source-specificity when considering psychiatric disorders in children with ASDs.
4. Nadel J, Aouka N, Coulon N, Gras-Vincendon A, Canet P, Fagard J, Bursztejn C. {{Yes they can! An approach of observational learning in low-functioning children with autism}}. {Autism};2011 (Mar 31)
Learning by doing and learning by observing are two facets of the tight coupling between perception and action discovered at the brain level. Developmental studies of observational learning still remain rare and even more rare are studies documenting the capacities of low-functioning children with autism to learn by observation. In the first investigation of this question, twenty nonverbal children with autism with a developmental age of 24 and 36 months, and twenty matched typical children, were presented with an experimental box requiring that a hierarchical sequence of subgoals be performed before it could be opened. A 9-day testing procedure included four presentations of the red box and two video demonstrations of how to open it. Two scores were computed, one concerning the number of sub-goals fulfilled and the other the relevant manipulations of the material. Within-group analyses revealed that only the typical children learned partly or fully the sequence of subgoals after the first video-demonstration. The addition of a second demonstration allowed the two subgroups with autism to learn partly or fully the sequence of subgoals. The differences between learning to manipulate and learning to produce a goal are discussed in terms of relationships between understanding actions and understanding action-effect relations.
5. Turner-Brown LM, Lam KS, Holtzclaw TN, Dichter GS, Bodfish JW. {{Phenomenology and measurement of circumscribed interests in autism spectrum disorders}}. {Autism};2011 (Mar 31)
Circumscribed interests (CI) are important and understudied symptoms that affect individuals with autism spectrum disorders (ASD). The present study sought to develop quantitative measures of the content, intensity and functional impairment of CI in 50 children with high-functioning ASD compared to an age-, IQ-, and gender-matched sample of 50 typically developing (TD) peers. The Interests Scale, a parent-rating questionnaire, and the Interview for Repetitive Behaviors, a semi-structured interview, were used to assess CI. Groups did not differ on the number of interests children held, but they did differ on types of interests and impairment associated with them. The interests of ASD participants were more likely to be nonsocial in nature (e.g. mechanical systems) than TD participants. Parents of children with ASD endorsed higher degrees of functional impairment on metrics including frequency, interference, resistance when interrupted, flexibility, and accommodation required, as well as less involvement of other people, than parents of children with TD. These findings suggest that interests of individuals with ASD differ qualitatively and in intensity from individuals with TD. The present study offers further support for the notion that CI reflect a clinically significant feature of ASD that warrants intervention in some children.
6. Koh HC, Milne E. {{Evidence for a Cultural Influence on Field-Independence in Autism Spectrum Disorder}}. {J Autism Dev Disord};2011 (Apr 1)
Field-independence, or weak central coherence, is a recognised phenotype of autism spectrum disorder (ASD). There is also evidence of cultural variation in this perceptual style, as neurotypical individuals from Western nations are more field-independent than neurotypical individuals from East-Asian nations. The majority of research on perceptual style in those with ASD has been carried out in Western nations therefore it is unclear whether increased field-independence in ASD is a culturally universal phenotype. Here, we assessed perceptual style in children with and without ASD from England and Singapore using the Children’s Embedded Figures Test and the Framed-Line Test. We found increased field-independence in the English participants with ASD only, suggesting that weak central coherence in ASD is not culturally universal.
7. Kourkoulou A, Leekam SR, Findlay JM. {{Implicit Learning of Local Context in Autism Spectrum Disorder}}. {J Autism Dev Disord};2011 (Apr 2)
Although previous research has reported impairments in implicit learning in individuals with ASD, research using one implicit learning paradigm, the contextual cueing task (Chun and Jiang in Cognitive Psychol 36:28-71, 1998), shows evidence of intact ability to integrate spatial contextual information. Using an adaptation of this paradigm, we replicated earlier findings showing that contextual cueing facilitates learning in ASD. Nevertheless, we found that exposure to repeated contexts that biased attention to local rather than global displays rendered it difficult for individuals with ASD to adapt to new trials. Thus, adaptive processes that allow one to respond flexibly and rapidly to new situations appear diminished in ASD when exposed to local spatial contexts. These findings have implications for practical learning strategies used in educational settings.
8. Merchan-Naranjo J, Mayoral M, Rapado-Castro M, Llorente C, Boada L, Arango C, Parellada M. {{Estimation of the Intelligence Quotient Using Wechsler Intelligence Scales in Children and Adolescents with Asperger Syndrome}}. {J Autism Dev Disord};2011 (Apr 1)
Asperger syndrome (AS) patients show heterogeneous intelligence profiles and the validity of short forms for estimating intelligence has rarely been studied in this population. We analyzed the validity of Wechsler Intelligence Scale (WIS) short forms for estimating full-scale intelligence quotient (FSIQ) and assessing intelligence profiles in 29 AS patients. Only the Information and Block Design dyad meets the study criteria. No statistically significant differences were found between dyad scores and FSIQ scores (t(28) = 1.757; p = 0.09). The dyad has a high correlation with FSIQ, good percentage of variance explained (R (2) = 0.591; p < 0.001), and high consistency with the FSIQ classification (chi (2)(36) = 45.202; p = 0.14). Short forms with good predictive accuracy may not be accurate in clinical groups with atypical cognitive profiles such as AS patients.
9. Reisinger LM, Cornish KM, Fombonne E. {{Erratum to: Diagnostic Differentiation of Autism Spectrum Disorders and Pragmatic Language Impairment}}. {J Autism Dev Disord};2011 (Apr 2)
10. Ortega-Garcia JA, Angulo MG, Sobrino-Najul EJ, Soldin OP, Puche-Mira A, Martinez-Salcedo E, Claudio L. {{Prenatal exposure of a girl with autism spectrum disorder to ‘horsetail’ (Equisetum arvense) herbal remedy and alcohol: a case report}}. {J Med Case Reports};2011 (Mar 31);5(1):129.
ABSTRACT: INTRODUCTION: Autism is a complex neurodevelopmental disorder in which the interactions of genetic, epigenetic and environmental influences are thought to play a causal role. In humans, throughout embryonic and fetal life, brain development is exquisitely susceptible to injury caused by exposure to toxic chemicals present in the environment. Although the use of herbal supplements during pregnancy is relatively common, little information is available on their association with fetal neurodevelopment. This is, to the best of our knowledge, the first report in the literature to associate a new plausible mechanism of neurodevelopmental toxicity with a case of autism spectrum disorder through a vitamin deficiency potentiated by concomitant use of herbal supplements and ethanol exposure. CASE PRESENTATION: We describe the pediatric environmental history of a three-year-old Caucasian girl with an autism spectrum disorder. We utilized her pediatric environmental history to evaluate constitutional, genetic, and environmental factors pertinent to manifestation of neurodevelopment disorders. Both parents reported prenatal exposure to several risk factors of interest. A year prior to conception the mother began a weight loss diet and ingested 1200mg/day of ‘horsetail’ (Equisetum arvense) herbal remedies containing thiaminase, an enzyme that with long-term use can lead to vitamin deficiency. The mother reported a significant weight loss during the pregnancy and a deficiency of B-complex vitamins. Thiamine (vitamin B1) deficiency could have been potentiated by the horsetail’s thiaminase activity and ethanol exposure during pregnancy. No other risk factors were identified. CONCLUSIONS: A detailed and careful pediatric environmental history, which includes daily intake, herbal remedies and ethanol exposure, should be obtained from all patients with autism spectrum disorder. Maternal consumption of ethanol and of herbal supplements with suspected or potential toxicity should be avoided during pregnancy. The prospective parents should perform preconception planning before pregnancy.
11. Beard CM, Panser LA, Katusic SK. {{Is excess folic acid supplementation a risk factor for autism?}}. {Med Hypotheses};2011 (Mar 29)
BACKGROUND: The objective was to assess the association between increasing autism incidence rates and the increasing dose of folic acid in prescription prenatal and pediatric vitamins. METHODS: We used published autism incidence rates from the Rochester Epidemiological Project in Rochester, MN, for 1976-1997. Additionally, we used the percent of prescription prenatal vitamins containing 1mg folic acid and the percent of prescription pediatric vitamins with any folic acid from Physicians’ Desk References for roughly the same time period. RESULTS: The Pearson product moment correlation coefficient (r) for the association between the percentage of prescription prenatal vitamins containing 1mg folic acid and research-identified autism incidence in Olmsted County was 0.87 [95% confidence interval (CI)=0.19-0.99]. In contrast, there was a weak association between pediatric vitamins containing any folic acid and autism incidence using the same statistical method (r=0.62, 95% CI=-0.38-0.95). CONCLUSIONS: If it is true that too little folic acid results in nervous tissue damage, as is accepted by the scientific community in regard to neural tube defects (NTDs), then it seems plausible that too much folic acid may result in nervous tissue damage associated with autism. Although the correlations described here do not provide proof of causation, these data provide an impetus for further study. Children who develop autism may be receiving a massive dose of folic acid in utero, as well as, after birth. It would be of interest to carry out a case-control study using medical record data to document folic acid intake for pregnant women whose offspring were later diagnosed with autism and controls.
12. Tansey KE, Hill MJ, Cochrane LE, Gill M, Anney RJ, Gallagher L. {{Functionality of promoter microsatellites of arginine vasopressin receptor 1A (AVPR1A): implications for autism}}. {Mol Autism};2011 (Mar 31);2(1):3.
ABSTRACT: BACKGROUND: Arginine vasopressin (AVP) has been hypothesized to play a role in aetiology of autism based on a demonstrated involvement in the regulation of social behaviours. The arginine vasopressin receptor 1A gene (AVPR1A) is widely expressed in the brain and is considered to be a key receptor for regulation of social behaviour. Moreover, genetic variation at AVPR1A has been reported to be associated with autism. Evidence from non-human mammals implicates variation in the 5′-flanking region of AVPR1A in variable gene expression and social behaviour. METHODS: We examined four tagging single nucleotide polymorphisms (SNPs) (rs3803107, rs1042615, rs3741865, rs11174815) and three microsatellites (RS3, RS1 and AVR) at the AVPR1A gene for association in an autism cohort from Ireland. Two 5′-flanking region polymorphisms in the human AVPR1A, RS3 and RS1, were also tested for their effect on relative promoter activity. RESULTS: The short alleles of RS1 and the SNP rs11174815 show weak association with autism in the Irish population (P = 0.036 and P = 0.008, respectively). Both RS1 and RS3 showed differences in relative promoter activity by length. Shorter repeat alleles of RS1 and RS3 decreased relative promoter activity in the human neuroblastoma cell line SH-SY5Y. CONCLUSIONS: These aligning results can be interpreted as a functional route for this association, namely that shorter alleles of RS1 lead to decreased AVPR1A transcription, which may proffer increased susceptibility to the autism phenotype.
