Genetically based correlates of serum oxytocin and testosterone in autism and schizotypy

Attenuated relationship between salivary oxytocin levels and attention to social information in adolescents and adults with autism spectrum disorder: a comparative study

BACKGROUND

Previous research studies have assessed the relationship between attention to social information and peripheral (e.g., plasma and salivary) oxytocin (OT) levels in typically developing (TD) children and children with autism spectrum disorder (ASD). A relationship between them was observed in TD children, but not in children with ASD. However, this relationship remains unexamined in other age groups. To clarify whether this lack of association is maintained throughout development in individuals with ASD, we aimed to assess the relationship between salivary OT levels and attention to social information in adolescents and adults with and without ASD.

METHODS

We recruited male adolescents and adults with ASD (n = 17) and TD participants (n = 24). Using the all-in-one eye-tracking system Gazefinder, we measured the percentage fixation time allocated to social information. We also measured the salivary OT levels and Autism Spectrum Quotient (AQ) of participants. Subsequently, we confirmed group differences and conducted a correlation analysis to investigate the relationships between these three measures.

RESULTS

Salivary OT levels did not show any significant difference between the ASD and TD groups and were negatively correlated with the AQ in the whole-group analysis, but not in within-group analysis. Individuals with ASD had significantly lower percentage fixation times than did TD individuals for eye regions in human faces with/without mouth motion, for upright biological motion, and for people regions in the people and geometry movies. The percentage of fixation for geometric shapes in the people and geometry movies was significantly higher in the ASD than in the TD group. In the TD group, salivary OT levels were positively correlated with percentage fixation times for upright biological motion and people and negatively correlated with inverted biological motion and geometry. However, no significant correlations were found in the ASD group.

CONCLUSIONS

Our exploratory results suggest that salivary OT levels in adolescents and adults with ASD are less indicative of attention to social stimuli than they are in TD adolescents and adults. It is suggested that their association is slightly weaker in adolescents and adults with ASD and that this attenuated relationship appears to be maintained throughout development.

Revisiting the overlap between autistic and schizotypal traits in the non-clinical population using meta-analysis and network analysis

The present study aimed to explore the relationship between autistic and schizotypal traits in the non-clinical population. We first conducted a meta-analysis to quantify the correlation between self-reported autistic traits and the three dimensions of schizotypal traits (positive, negative and disorganization). The strongest correlation was found between autistic traits and negative schizotypal traits (r = 0.536, 95% CI [0.481, 0.586]), followed by the disorganization (r = 0.355, 95% CI [0.304, 0.404]) and positive (r = 0.256, 95% CI [0.208, 0.302]) dimensions. To visualize the partial correlations between dimensional behavioural traits, we constructed a network model based on a large sample of college students (N = 2469). Negative schizotypal traits were strongly correlated with autistic social/communicative deficits, whereas positive schizotypal traits were inversely correlated with autistic-like traits, lending support to the psychosis-autism diametrical model. Disentangling the overlapping and diametrical structure of autism and schizophrenia may help to elucidate the aetiology of these two neurodevelopmental disorders.

The role of cholesterol metabolism and various steroid abnormalities in autism spectrum disorders: A hypothesis paper

Based on evidence from the relevant research literature, we present a hypothesis that there may be a link between cholesterol, vitamin D, and steroid hormones which subsequently impacts on the development of at least some of the "autisms" [Coleman & Gillberg]. Our hypothesis, driven by the peer reviewed literature, posits that there may be links between cholesterol metabolism, which we will refer to as "steroid metabolism" and findings of steroid abnormalities of various kinds (cortisol, testosterone, estrogens, progesterone, vitamin D) in autism spectrum disorder (ASD). Further research investigating these potential links is warranted to further our understanding of the biological mechanisms underlying ASD. Autism Res 2017. © 2017 The Authors Autism Research published by Wiley Periodicals, Inc. on behalf of International Society for Autism Research. Autism Res 2017, 10: 1022-1044. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.