The hormone oxytocin, which is produced in high concentration during childbirth and lactation, may improve the social skills of people with high−functioning autism, according to a new study in Proceedings of the National Academy of the Sciences. Oxytocin is believed to stimulate mother−infant bonding, and previous studies have found that people suffering from autism have lower−than−normal levels of this hormone than normal individuals. Diminished social skills and interaction are well−documented hallmarks of the spectrum disorder autism.

Researchers found that the participants in the oxytocin group looked more often at the eyes or whole faces than did those in the placebo group (these participants tended to look at only the mouths or turned away from the photos completely).

In the new study, Angela Sirigu at the Centre de Neuroscience Cognitive in Lyon and colleagues administered oxytocin or placebo via a nasal spray to 13 participants who had been diagnosed with either high−functioning autism or Asperger’s syndrome. The participants were then asked to play a virtual ball game, in which they had to interact with (pass the ball back and forth to) virtual players. Those who had inhaled the oxytocin showed differences in the way they approached the other “players,” choosing the most “cooperative” virtual player preferentially over the others – rather than choosing players at random, as those in the placebo group appeared to do.

In another test, in which the participants were asked to look at photographs of people’s faces, the researchers found that the participants in the oxytocin group looked more often at the eyes or whole faces than did those in the placebo group (these participants tended to look at only the mouths or turned away from the photos completely). The eyes are considered to be “socially important” visual cues.

The researchers were able to confirm differences in circulating oxytocin levels before and after administration of the hormone. They noted significantly higher levels after the treatment, which corresponded to the differences in behavior observed during the social skills tests.

Surugu and her team conclude that their study “demonstrate[s] that oxytocin can promote social approach and social comprehension in patients with autism.” However, while the results are encouraging, it is also clear that much more research will be needed to evaluate the treatment further. One key question will be to determine the best method of administration and dosing: since inhalation provides only short−term benefits (on the order of minutes), research will also need to look at how treatments might work more effectively over the long−term.