Effects of Oxytocin on Social Perception in Youth with ASD: A MEG Study

Background: Autism spectrum disorders (ASD) are neurodevelopmental conditions characterized partly by core social dysfunction, impaired social motivation and interaction. Recent discoveries draw attention to the impact that intranasal administration of the neuropeptide Oxytocin (OT) may have on social behavior and perception in ASD. Several brain imaging studies in individuals with ASD highlighted OT's capacity to modulate "the social brain", however, there is a gap in the literature regarding the influences of OT on neural temporal dynamics. Thus, a comprehensive understanding of OT's influences on the brain in ASD requires the use of methods with superior temporal resolution, especially in children.

Objectives: This study aims to explore the impact of OT on temporal dynamics in ASD using magnetoencephalography (MEG) during a well-validated social perception paradigm. Extending on previous findings which pointed to OT modulation of ERP components in typically developed (TD) adults during a similar task, we focused on the P100, N170 and P250 components, which also tend to show atypical patterns in ASD. We hypothesize that OT will modulate the amplitude and latency of these components to resemble those of an age-matched TD group.

Methods: As a part of an ongoing study, we present initial data from seven youth with ASD (aged 12-18), who received a single dose of intranasal OT (24IUs) in a double-blind placebo-controlled study. Forty five minutes following administration, participants were scanned in the MEG. During each scan participants were presented with pictures of emotional eyes or vehicles and asked to identify the picture theme. An aged-matched TD group served as a baseline for comparison. For ethical reasons, TD participants did not receive OT/placebo.

Results: Preliminary results indicate that in our components of interest, OT indeed normalized brain activity in ASD to be more similar to that of the TD group (enhancing P100 and P250 amplitudes while reducing N170 amplitude). This effect was visible only for the amplitude but not for the latencies of the components. Interestingly, while this effect was present in all three components in the emotional identification condition, in the vehicles recognition condition, OT influenced only the P100 component.

Conclusions: These initial results provide the basis for essential understanding of the influences of OT on ASD neural activation from a new perspective. Being the first exploration of the impact of OT on the brain in youth with ASD using MEG, this study indicates that OT can modulate early stages of visual perception, especially during social stimuli. Our study addresses core issues regarding OT’s impact on the social brain and social behavior in ASD and thus, in the future, may promote the development of more effective treatments for social deficits.