Intranasal oxytocin attenuates insula activity in response to dynamic angry faces.

The effects of intranasal oxytocin on amygdala activity during emotional perception are often mixed. Given that the brain is organized into networks of interconnected areas, functional connectivity might provide an effective way to further understand the oxytocin effect. The aim of the present study was to investigate whether oxytocin administration affects amygdala activity and its functional connectivity during dynamic facial expression perception. Using a between-group, double-blind, placebo-controlled design, 55 participants were randomly assigned to groups receiving a single dose of 24 IU oxytocin or a placebo via intranasal administration. An implicit emotional task was employed to investigate the effect of oxytocin on neural responses to dynamic angry, neutral, and happy facial expressions with fMRI. Participants were instructed to respond only when the inverted dynamic faces were presented. The results indicated that oxytocin attenuated activation of insula and emotional processing-related regions (e.g., ACC, thalamus, and MFG) during the viewing of dynamic angry faces. However, functional connectivity between the regions involved in the perception of dynamic angry faces was not changed following oxytocin administration. The present findings may contribute to our understanding of the anxiolytic effects of oxytocin and eventually facilitate human clinical applications.