Over-Selectivity is Related to Autism Quotient and Empathizing, But not to Systematizing

The influence of NRXN1 on systemizing and the brain structure in healthy adults

Certain behavioral characteristics of autism spectrum disorder can be found in otherwise healthy people. Individuals with difficulties in social adaptation may have subclinical autistic traits; however, effective biomarkers of these traits have not yet been established. There is a dire need for objective indices of these traits that combine behavior, brain images, and genetic information. In this study, we examined the association among a single nucleotide polymorphism of NRXN1 (rs858932; C/G), autistic traits, and brain structure in 311 healthy adults. We found that carriers of minor alleles (carriers of the G-allele) had significantly higher systemizing scores than major-allele (C-allele) homozygotes. Furthermore, the regional white matter volume in the right anterior limb of the internal capsule was significantly greater in carriers of the G-allele than in C-allele homozygotes. To the best of our knowledge, this is the first report of NRXN1 rs858932 being involved in systemizing and the brain structure of healthy adults. Our findings provide insight into the effects of genetics on autistic traits and their respective neural substrates.

Associations among parent and teacher ratings of systemizing, vocabulary and executive function in children with autism spectrum disorder

Individuals with Autism Spectrum Disorder (ASD) show a heightened drive toward systemizing, which is the capability to analyze, or the drive to construct, a rule-based system. In addition, executive function deficits as well as diminished language capacity and vocabulary have been consistently demonstrated in individuals with ASD. The primary purpose of this study was to create a model to understand how these constructs interact in children with ASD. Forty-six children diagnosed with ASD along with their parents and teachers participated. All children completed standardized vocabulary testing. For each child, one parent and one teacher completed executive function and systemizing scales. For parents and teachers, systemizing was significantly associated with vocabulary. For parents, systematizing was significantly associated with all executive function subscales, however, for teachers, systemizing was only significantly associated with half of the executive function subscales. The mediation model indicated that the relationship between vocabulary and systemizing was fully mediated by executive function for parents but the model was not significant for teachers. This model demonstrates that systemizing, vocabulary and executive function should not be studied in isolation when attempting to understand the behaviors of children with ASD and can help us to better plan educational and therapeutic interventions.

Extension of the stimulus control produced by three procedures for teaching pseudowords discrimination

Abstract This study investigated the effects of pseudoword discrimination training that either required or didn’t require selection responses upon control by stimulus elements and recombination of elements, and upon stimulus observation. Eight undergraduate students were exposed to two conditions with discriminative training and stimulus control test. Condition SEL required selecting the S+, and condition OBS only required observation. Test results suggest that selection responses did not affect control by the elements or the recombination of elements in the pseudowords. Four participants presented restricted stimulus control. This control was extended in the additional DOR condition, which required differential observation of the elements, and was accompanied by increases in S+ observation. Increased stimulus control, promoted by the DOR, should still be evaluated independently of previous teaching conditions.