A paper to be presented at the 2012 international Society for Autism Research used fMRI to find that a single dose of inhaled oxytocin increased activity in areas of the brain that process social activity.

The researchers' conclusion:

These results provide the first, critical steps towards devising more effective treatments for the core social deficits in autism which may involve a combination of validated clinical interventions with an administration of oxytocin. Such a treatment approach will fundamentally alter for the better our understanding of autism and its treatment.

LeftBrainRightBrain has more info and a link to the study, led by I. Gordon at Yale.