Autism is a disease characterized by difficulties in communicating effectively with other people and developing social relationships. The team led by Angela Sirigu at the Centre de Neuroscience Cognitive (CNRS) has shown that the inhalation of oxytocin, a hormone known to promote mother-infant bonds and social relationships, significantly improved the abilities of autistic patients to interact with other individuals.
To achieve this, the researchers administered oxytocin to 13 autistic patients and then observed their social behavior during ball games and during visual tests designed to identify ability to recognize faces expressing different feelings. Their findings, published in PNAS on 15 February 2010, thus reveal the therapeutic potential of oxytocin to treat the social disorders from which autistic patients suffer.
Oxytocin is a hormone that promotes delivery and lactation. It plays a crucial role in enhancing social and emotional behavior. Previous studies that measured the levels of this hormone in the blood of patients showed that it was deficient in those with autism.
The team led by Angela Sirigu at the Centre de Neuroscience Cognitive in Lyon thus advanced the hypothesis that a deficit in this hormone might be implicated in the social problems experienced by autistic subjects. The team, working in collaboration with Dr Marion Leboyer at Hôpital Chenevier in Créteil, examined whether the administration of oxytocin could improve the social behavior of 13 individuals with high-functioning autism (HFA) or Asperger syndrome (AS). In both these forms of autism, patients retain normal intellectual and linguistic skills but are unable to engage spontaneously in social situations. Thus, during a conversation, these patients turn their heads and avoid eye contact with other people.
First of all, the researchers observed the social behavior of the patients while they were interacting with three other people during a ball tossing game. Three profiles were represented: a player who always returned the ball to the patient, a player who did not return the ball, and finally a player who indiscriminately returned the ball to the patient or to other players. Each time the patient received the ball, he or she won a sum of money. The game was restarted ten times in order to allow the patient to identify the different profiles of his/her partners and act accordingly. Under a placebo, the patients returned the ball indiscriminately to the three partners. However, patients treated with oxytocin were able to discriminate between the different profiles and returned the ball to the most cooperative partner.