Executive functions in youths with autism spectrum disorder and their unaffected siblings.

BACKGROUND: Executive dysfunction is one of the main cognitive theories of autism spectrum disorder (ASD). Despite evidence of deficits in executive functions in individuals with ASD, little is known about executive dysfunctions as candidate cognitive endophenotypes for ASD. In this study, we investigated executive functions in youths with ASD, their unaffected siblings and typically developing controls (TDC). METHODS: We recruited 240 youths with a clinical diagnosis of ASD (aged 6-18 years), 147 unaffected siblings of ASD youths, and 240 TDC youths. TDC youths were recruited based on the age and sex distribution of the ASD youths. Participants were assessed using the verbal Digit Span test and four executive function tasks from the Cambridge Neuropsychological Test Automated Battery, including Intra-dimensional/Extra-dimensional Shift (I/ED), Spatial Span (SSP), Spatial Working Memory (SWM), and Stocking of Cambridge (SoC). RESULTS: ASD youths, relative to TDC, performed significantly worse in executive function tasks assessing verbal working memory (forward and backward digit span), set-shifting (I/ED), visuospatial working memory (SSP, SWM), and planning/problem solving (SoC). Furthermore, unaffected siblings, relative to TDC, performed worse in forward and backward digit recalls and made more errors in SWM. These results were independent of the effects of age, sex, IQ, and symptoms of attention-deficit/hyperactivity disorder. CONCLUSIONS: Our findings support impaired executive functions in youths with ASD. However, unaffected siblings were mostly unimpaired except in the areas of verbal and spatial working memory, which may be potential cognitive endophenotypes for ASD.

Gray matter volume alteration is associated with insistence on sameness and cognitive flexibility in autistic youth.

Restricted and repetitive behaviors (RRBs) are hallmark characteristics of autism spectrum disorder (ASD). Previous studies suggest that insistence on sameness (IS) characterized as higher-order RRBs may be a promising subgrouping variable for ASD. Cognitive inflexibility may underpin IS behaviors. However, the neuroanatomical correlates of IS and associated cognitive functions remain unclear. We analyzed data from 140 autistic youth and 124 typically developing (TD) youth (mean age = 15.8 years). Autistic youth were stratified by median-split based on three current IS items in the autism diagnostic interview-revised into two groups (high, HIS, n = 70, and low, LIS, n = 70). Differences in cognitive flexibility were assessed by the Cambridge neuropsychological test automated battery (CANTAB). T1-weighted brain structural images were analyzed using voxel-based morphometry (VBM) to identify differences in gray matter (GM) volume among the three groups. GM volume of regions showing group differences was then correlated with cognitive flexibility. The HIS group showed decreased GM volumes in the left supramarginal gyrus compared to the LIS group and increased GM volumes in the vermis VIII and left cerebellar lobule VIII compared to TD individuals. We did not find significant correlations between regional GM volumes and extra-dimensional shift errors. IS may be a unique RRB component and a potentially valuable stratifier of ASD. However, the neurocognitive underpinnings require further clarification. LAY SUMMARY: The present study found parietal, temporal and cerebellar gray matter volume alterations in autistic youth with greater insistence on sameness. The findings suggest that insistence on sameness may be a useful feature to parse the heterogeneity of the autism spectrum yet further research investigating the underlying neurocognitive mechanism is warranted.

Promotion and implementation effectiveness of World Health Organization's Caregiver Skills Training program in Taiwan.

The World Health Organization (WHO) developed the Caregiver Skills Training for Families of Children with Developmental Delays and Disabilities (CST) with support from Autism Speaks to address the resource gaps and worldwide needs for interventions for children with developmental disorders or delays, especially those with autism spectrum disorder (ASD), and their families. Evidence has indicated that parent-mediated interventions benefit both caregivers and children by strengthening caregivers' knowledge and confidence and children's social communication skills and behavioral regulation. The CST-Taiwan team began the prepilot field trial in 2017 and developed the project to serve families in various locations. This study (1) delineated the adaptations and promotion of CST-Taiwan; (2) determined the program's effectiveness in the promotional stage, in terms of caregiver and child outcomes, and (3) examined the maintenance of its effects. The materials, delivery, and facilitator training procedure of the original CST were adapted to Taiwan. The quantitative data indicated that CST-Taiwan is a promising program, it positively affected caregiver knowledge and confidence and reduced the severity of the children's autistic symptoms. The 3-month follow-up results suggested that the effects persisted. Thus, CST-Taiwan, and its promotional strategies are feasible and effective.