Nasal inhalation of oxytocin, a hormone linked with romantic love and mother-to-baby bonding, may help people with autism become more sociable, according to a French study.

A team led by Angela Sirigu of the Centre for Cognitive Neuroscience in Lyon, France, tried the experiment after previous research found that blood levels of oxytocin are low among individuals with autism, a condition that afflicts social behaviour.

Oxytocin was tested among 13 patients suffering on high-functioning autism patients or with Asperger's syndrome.

The individuals had normal intellectual capacities but had problems in making contact in social situations.

To measure behavioural changes, the researchers observed the patients and controls, who were not given oxytocin, in a virtual game of passing a ball.

They then measured attentiveness to socially important cues when the patients viewed pictures of human faces.

Patients who had inhaled oxytocin showed more attentiveness to visual cues when viewing human faces and were more likely to process social cues during the virtual ball passing game than controls in both experiments, the authors said.

The study, published on Monday in the US journal Proceedings of the National Academy of Sciences, is cautious, saying there is wide individual variation in social responses.

Even so, the outcome should unlock future studies on whether long-term use of oxytocin could bolster confidence and help social behaviour amongst people afflicted by autism, say the authors.