Oral, similar to intranasal, administration of oxytocin decreases top-down social attention

The neuropeptide oxytocin (OXT) modulates social cognition by increasing attention towards social cues and may have therapeutic potential for impaired social attention in disorders such as autism. Intranasal administration of OXT is widely used to examine its functional effects in both adults and children and is assumed to enter the brain directly via this route. However, OXT can also influence brain function via increased blood concentrations and we have recently shown that orally (lingual) administered OXT also modulates neural responses to emotional faces and may be better tolerated for therapeutic use. Here, we examined if 24IU OXT administered orally can facilitate social attention. In a randomized, placebo-controlled, pharmacological study we used a validated emotional anti-saccade eye-tracking paradigm to explore effects of oral OXT on bottom-up and top-down attention processing in 80 healthy male subjects. Our findings showed in terms of top-down attention, oral OXT increased errors for both social (angry, fearful, happy, sad and neutral emotion faces) and non-social stimuli (oval shapes) in the anti-saccade condition but only increased response latencies in the social condition. It also significantly reduced post-task state anxiety but this was not correlated with task performance. Comparison with our previous intranasal OXT study using the same task revealed both routes have a similar effect on increasing anti-saccade errors and response latencies and reducing state anxiety. Overall, findings suggest that oral administration of OXT produces similar effects on top-down social attention control and anxiety as intranasal administration and may therefore have therapeutic utility.