Intranasal oxytocin administration has been shown to influence a variety of outcomes related to social behavior and cognition in clinical and typical samples. One possibility for these diverse effects is that oxytocin alters functional connectivity of social brain regions. However, this hypothesis has not been tested in autistic women. Using a cross-over design, we examined the effects of a single 24IU dose of oxytocin relative to placebo on resting-state functional connectivity in 16 autistic women and 23 non-autistic women matched for age and IQ. Connectivity among social brain regions (amygdala, anterior cingulate cortex (ACC), insula, medial prefrontal cortex (mPFC), and temporoparietal junction (TPJ)) was examined and compared between drug conditions and groups. We found a main drug effect for ACC-insula connectivity, with lower mean connectivity in the oxytocin condition. Significant Drug×Group interactions were also observed, such that oxytocin tended to increase connectivity among amygdala, insula, mPFC, and TPJ in autistic women but decrease connectivity in non-autistic women. Among autistic women, oxytocin-associated increases of moderate effect size were observed for insula-left TPJ and left amygdala-right TPJ connectivity, which attenuated large group connectivity differences observed in the baseline condition. Exploratory analyses suggested that women whose salivary oxytocin levels were more elevated from baseline by oxytocin administration tended to show larger increases in connectivity. These findings offer further evidence that oxytocin influences resting-state connectivity, with effects moderated by individual differences in endogenous hormone levels and clinical phenotype.
Diagnosis of Autism Spectrum Disorders Using Temporally Distinct Resting-State Functional Connectivity Networks
