Mechanisms of Diminished Attention to Eyes in Autism

Objective: Two hypotheses, gaze aversion and gaze indifference, are commonly cited to explain a diagnostic hallmark of autism: reduced attention to others’ eyes. The two posit different areas of atypical brain function, different pathogenic models of disability, and different possible treatments. Evidence for and against each hypothesis is mixed but has thus far focused on older children and adults. The authors evaluated both mechanistic hypotheses in two sets of experiments at the time of initial diagnosis.

Method: Eye-tracking data were collected in 86 2-year-olds: 26 with autism, tested at initial diagnosis; 38 matched typically developing children; and 22 matched developmentally delayed children. In two experiments, the authors measured response to direct and implicit cueing to look at the eyes.

Results: When directly cued to look at the eyes, 2-year-olds with autism did not look away faster than did typically developing children; their latency varied neither categorically nor dimensionally by degree of eye cueing. Moreover, direct cueing had a stronger sustained effect on their amount of eye-looking than on that of typically developing children. When presented with implicit social cues for eye-looking, 2-year-olds with autism neither shifted their gaze away nor more subtly averted their gaze to peripheral locations.

Conclusions: The results falsify the gaze aversion hypothesis; instead, at the time of initial diagnosis, diminished eye-looking in autism is consistent with passive insensitivity to the social signals in others’ eyes.

Keywords: Autism; Child Psychiatry; Eye Contact; Gaze Aversion.

Background: Previous work has documented lower vocalization rate and consonant acquisition delays in toddlers with autism spectrum disorder (ASD). We investigated differences in these variables at 12, 18, and 24 months in toddlers at high and low risk for ASD.

Method: Vocalization rate and number of different consonants were obtained from speech samples from a prospective study of infant siblings of children with ASD. Three groups were compared: 18 toddlers at low risk for ASD (low-risk control), 18 high-risk siblings without ASD (HRA-), and 10 high-risk siblings with ASD (HRA+).

Results: All groups’ mean language scores were within the normal range. HRA+ toddlers showed consistently lower vocalization rate; vocalization rate did not predict number of different consonants at 12 months for HRA+. HRA-, not HRA+, toddlers had the smallest number of different consonants and produced significantly fewer different consonants than predicted by their vocalization rate at 12 months. Consonant-acquisition trajectories differed between groups, with HRA- showing the greatest increase from 12 to 18 months.

Conclusion: Lower vocalization rate was not associated with reduced number of different consonants in these toddlers. Between-groups differences in developmental trajectories are discussed in the context of the social feedback loop and differential ability to benefit from adult feedback between groups.

Although evidence-based practices for autism spectrum disorders exist, they are often not effectively incorporated into school-based programs, indicating a need for enhanced training strategies for educators. This study examined the effects of immediate video feedback during coaching for teachers and paraprofessionals learning Classroom Pivotal Response Teaching (CPRT). Special education teachers, along with their classroom paraprofessionals, were randomly assigned to a coaching as usual (CAU) or a coaching with video enhancement (VE) condition. Both groups received both verbal and written feedback regarding strengths and weaknesses of their CPRT implementation. Additionally, the VE condition received video feedback during their coaching sessions. Overall, teachers demonstrated higher fidelity of implementation than paraprofessionals, t(44) = −2.73, p < .01, but no significant group differences were identified between VE and CAU conditions. Univariate analysis of variance models were conducted to examine the relationship between participant satisfaction regarding overall quality of the training and highest percentage of CPRT components passed, F(2, 37) = 3.93, p = .03. Results indicate use of the iPad may impact training outcomes and participant satisfaction with training procedures and add to the very limited literature on how technology may be used to enhance in-service training for teachers.Keywords group design, methodologies, professional development, tablets, iPad, technology

Recent research suggests that children with autism spectrum disorder (ASD) may now be reliably identified in later infancy, highlighting the need for empirically-validated interventions for infants and toddlers with early symptoms of ASD. Using a multiple baseline design across 15- to 21-month-old toddlers, this study implemented a brief, parent-mediated, Pivotal Response Treatment program, focusing on improving expressive communication. The results indicated that verbal communication improved as a consequence of the intervention, with concomitant improvements in untreated areas for all participants. Following the intervention, symptoms of autism decreased and parents reported satisfaction with the program’s ease of implementation and observed child gains. The results are discussed in terms of developing very early interventions to improve developmental trajectories for infants and toddlers.

Keywords: Autism; Early intervention; Pivotal response treatment; Social communication; Toddlers.

Pivotal response treatment (PRT) is an evidence-based behavioral intervention based on applied behavior analysis principles aimed to improve social communication skills in individuals with autism spectrum disorder (ASD). PRT adopts a more naturalistic approach and focuses on using a number of strategies to help increase children’s motivation during intervention. Since its conceptualization, PRT has received much empirical support for eliciting therapeutic gains in greater use of functional social communication skills in individuals with ASD. Building upon the empirical evidence supporting PRT, recent advancements have increasingly turned to using interdisciplinary research integrating neuroimaging techniques and behavioral measures to help identify objective biomarkers of treatment, which have two primary purposes. First, neuroimaging results can help characterize how PRT may elicit change, and facilitate partitioning of the heterogeneous profiles of neural mechanisms underlying similar profile of behavioral changes observed over PRT. Second, neuroimaging provides an objective means to both map and track how biomarkers may serve as reliable and sensitive predictors of responder profiles to PRT, assisting clinicians to identify who will most likely benefit from PRT. Together, a better understanding of both mechanisms of change and predictors of responder profile will help PRT to serve as a more precise and targeted intervention for individuals with ASD, thus moving towards the goal of precision medicine and improving quality of care. This review focuses on the recent emerging neuroimaging evidences supporting PRT, offering current perspectives on the importance of interdisciplinary research to help clinicians better understand how PRT works and predict who will respond to PRT.

Keywords: ASD; PRT; biological motion; biomarkers; neuroimaging; precision medicine.

Background: Phelan-McDermid syndrome (PMS) occurs as a result of a chromosomal abnormality, most frequently
deletion, in the long arm of chromosome 22, involving the SHANK3 gene. Our goal was to prospectively assess the
neurological phenotype in this syndrome.
METHODS: Twenty-nine participants were recruited from ongoing studies in PMS at the Seaver Autism Center. They
had a structured, uniform neurological examination performed by a pediatric neurologist (Y.F.). Abnormal findings
were graded as mild, moderate or severe. In addition, reports of seizures, magnetic resonance imaging (MRI) and
electroencephalograms (EEG) were reviewed. We calculated the frequency and severity of neurological
abnormalities, as well as correlations between items on the neurological examination and items on the Mullen Scales
of Early Learning and on the Vineland Adaptive Behavioral Scales (VABS).
RESULTS: Hypotonia, abnormal gait, fine motor coordination deficits, and expressive and receptive language delays
were present in all participants. Attention deficits were present in 96% (severe in 62%), and abnormal visual tracking
was present in 86%. A history of seizures was obtained in 44.8% of participants but 46.1% of these were febrile only.
Of the 13 EEG reports available for review – 69.2% were abnormal- with epileptic features present in 53.8%.
Abnormalities were present in 62.5% of MRI reports. Correlations were found between neurological abnormalities
and scores on the Mullen and Vineland Scales.
CONCLUSIONS: Neurological abnormalities are very common in PMS and are correlated with measures of cognitive
and adaptive functioning. The neurological examination may be used for clinical diagnosis, identification of PMS
phenotypes, and, in the future, for evaluation of therapy.

Background: Autism spectrum disorder (ASD) is associated with impaired face processing. The N170 event-related potential (ERP) has been considered a promising neural marker of this impairment. However, no quantitative review to date has integrated the literature to assess whether the N170 response to faces in individuals with ASD differs from that of typically developing (TD) individuals.

Methods: This meta-analysis examined the corpus of literature investigating difference in N170 response to faces in individuals with ASD and without ASD. Data from 23 studies (NASD = 374, NTD = 359) were reviewed. Meta-analysis was used to examine the effect size of the difference in N170 latency and amplitude among individuals with ASD and without ASD. Analyses were also conducted examining hemispheric differences, potential moderators, and publication bias.

Results: On average, N170 latencies to faces were delayed in individuals with ASD, but amplitudes did not differ for individuals with ASD and TD individuals. Moderator analyses revealed that N170 amplitudes were smaller in magnitude in the ASD participants relative to the TD participants in adult samples and in those with higher cognitive ability. However, effects differed as a function of hemisphere of recording. No evidence of publication bias was found.

Conclusions: Atypicality of N170-particularly latency-to faces appears to be a specific biomarker of social-communicative dysfunction in ASD and may relate to differential developmental experiences and use of compensatory cognitive mechanisms. Future research should examine phenotypic differences that contribute to N170 heterogeneity, as well as specificity of N170 differences in ASD versus non-ASD clinical populations, and N170 malleability with treatment.

Keywords: Autism spectrum disorder (ASD); Electroencephalography (EEG); Event-related potential (ERP); Face processing; Meta-analysis; N170.