Oxytocin and Social Interaction
First published: July 1, 2013
Humans are innately social beings. Our lives revolve around living with family, bonding with loved ones, getting through work and school, and communicating with strangers. As part of our day-to-day functioning in all these situations, we need to remember individuals we meet regularly, establish trust, cooperate and connect with them in positive ways. However, children with autism spectrum disorder (ASD) face significant challenges in these areas that prevent them from forming close relationships with family and achieving good outcomes in education and employment later in life.
Researchers have found that the hormone oxytocin plays a role in many aspects of social awareness1,2,3, and they have been investigating whether it could benefit children with autism4,5,6,7,8,9.
Parents of children with autism who have participated in clinical trials of oxytocin report that it has been effective in enhancing their communication and social skills3.
Dr. Sue Carter, a professor of psychiatry at the University of North Carolina, Chapel Hill, explains that it is understandable that family members would consider using oxytocin supplements to help them bond with their loved ones with autism.
"Since other medication has not been able to treat social and communication deficits in autism, oxytocin seems like an attractive option because it has some capacity to enhance social engagement," she says.
But, Dr. Carter and other researchers warn that oxytocin has not been studied thoroughly, and administering it to children may be a step too far, too soon.
What is oxytocin?
Oxytocin plays a role in many aspects of social functioning. For example, children and adults with ASD spend less time looking at others' eyes, but after they received supplemental oxytocin as part of a study, the amount of time spent looking into others' eyes increased4,10,11,12.
"This didn't make you socially adept, but the individuals treated with oxytocin became more socially tuned in," Dr. Carter explains.
The hormone also helps people figure out which emotions others are feeling from their facial expressions and tone of voice. It promotes social learning. That is, it helps people remember such things as names, faces, and conversations13,4,5. It also regulates a person's emotional and behavioral response to stress and improves cooperation by increasing trust7,4.
Oxytocin levels in autism
Because of these connections, researchers have been exploring the relationship between oxytocin and sociability in those with autism.
A 1998 study was the first to find a link between the two. It found that children with autism had lower oxytocin levels than typically-developing ones. It also showed that children without ASD experienced a surge of oxytocin before the onset of puberty but children on the spectrum did not15.
The results of more recent studies vary widely. A study done in The Netherlands found higher oxytocin levels in adults with ASD than in healthy participants16. Another study found lower oxytocin levels in children with autism, but at the same time, they had higher levels of the hormone's variant that the body converts oxytocin to17.
Does oxytocin improve social interaction?
Besides not having concrete answers about the oxytocin levels found in individuals with ASD, researchers have not found consistent improvements in all aspects of sociability.
Many studies of oxytocin and autism were 'case studies', in which the researcher looked carefully at the effect of the treatment on one person8. Other studies involved only small numbers of people4,5,8,9. Because of the size of these studies, it is hard to draw any conclusions. Calculations based on a small number of observations can be misleading and may not represent the true picture. In addition, each study looked for improvements in only one aspect of social awareness, for instance, the ability to figure out emotions from facial expressions, but did not observe changes in other aspects, such as cooperation and trust4,5,8,9. A large number of studies that showed positive effects of oxytocin were done on individuals without ASD14,6,11,12. Some of them also found that oxytocin affected social behavior in negative ways; oxytocin increased envy, mistrust and prejudice against those perceived to be different18.
One French study found that oxytocin had the desired effect in some people, had a weak effect in others, and did not affect some individuals at all4.
These findings suggest that in most cases, the effect of the hormone depended on the situation and the individuals19. Social experiences in early life could also affect how the hormone really works21-- another reason for caution in giving the hormone to children.
Pitocin or synthetic oxytocin
Besides social functioning, oxytocin plays a role in various aspects of reproduction, including inducing labor in pregnant women20. Physicians use synthetic oxytocin, sold under the trade name Pitocin, to induce labor in women who have trouble going into labor on their own, or if they experience delays.
There have been concerns of whether giving the hormone externally to pregnant women leads to autism in their children21. However, research studies have disproved the connection, showing no difference in the rate at which Pitocin was used to induce the deliveries of children with autism and typically developing children22,23.
However, a study involving over 625,000 subjects in North Carolina found that pregnant women who were given external oxytocin to induce and augment labor had children who were later diagnosed with ASD, but it is still unclear if this caused autism. The study did not look into a possible link between the autism diagnosis and other factors such as the mother's exposure to medication before or during pregnancy, any injury to the newborn's nervous system soon after birth, or the father's age24.
Possible long-term effects of oxytocin
Oxytocin, however, has the potential to affect sexual behavior.
Dr. Karen Bales, a psychology professor at the University of California, Davis, has been studying the long-term effects of oxytocin on social and sexual behavior in animals. Her research has found that males and females react differently to the hormone, and that the response to different doses of oxytocin varies from one individual to another25,26.
Because of this and other studies, researchers warn that supplementing a hormone can have wide-reaching consequences. Besides their main functions, hormones have the potential to travel to different parts of the body. Dr. Bales says that in oxytocin's case, it is the heart, brain, kidneys, and anywhere there is smooth muscle. Adding oxytocin, she explains, could affect the function of these organs as well.
"Oxytocin has many health benefits and it is a part of the immune system, but it is also a very delicate system," Dr. Carter says. "So going in and disrupting it with a drug without knowing the consequences, is potentially dangerous."