The debate about whether to breastfeed or formula-feed infants has stirred up controversy over the years as anecdotal and medical research has both supported and disproven the alleged benefits of breast milk. No matter what side of the fence you stand on, a hormone released during breastfeeding could potentially be used to treat developmental disorders, such as autism. According to a recent study published in the journal Proceedings of the National Academy of Sciences, oxytocin — the love, cuddle, and breastfeeding hormone — may help babies develop social skills.

"It was important to test whether oxytocin would promote social behaviors in infants in the same respects as it appears to promote social interaction among adults,” said Elizabeth Simpson, first author of the study of the National Institutes of Health’s Eunice Kennedy Shriver National Institute of Child Health and Human Development, in the University of Massachusetts Amherst news release. Early caregiver-infant interactions are important for the socio-emotional and cognitive development of infants, and the breastfeeding hormone affects these interactions. While it is known oxytocin increases certain social behaviors in adults, little is known about the effects of the hormone on primate infants, including humans.

The team of American and Italian researchers from UMass Amherst and the University of Parma, Italy, sought to investigate whether oxytocin would increase affiliate social behavior by monitoring a group of young rhesus monkeys. The baby monkeys were tested on their ability to imitate two facial gestures associated with social interaction: lip smacking and tongue protrusion.

In lip smacking, the lips are protruded and open, then smacked together repeatedly, while tongue protrusion involves a brief protrusion and retraction of the tongue, or simply your tongue in and out. Typically, the rhesus mother engages in lip smacking with their infants in the first month after giving birth. Tongue protrusion is only imitated by monkeys when their human caregivers display it.

The baby monkeys’ ability to imitate the two gestures was tested after they inhaled oxytocin in the first two weeks after birth. This was done for a total of three times a day, every other day. The human caregivers did the facial gestures in the same order as the infant monkeys while recording their responses. The infant monkeys inhaled a spray dose of oxytocin in one session and a saline dose in the other. The doses were delivered through an inhalation mask that was gently placed over their face.

The findings revealed monkeys were more communicative, making facial gestures more frequently when they saw their caregivers, after receiving oxytocin compared to when they received saline. Although the monkeys were more likely to engage in lip smacking than tongue protrusion, they were still found to engage in either of these gestures more so than after exposure to saline. When it came to gesturing frequency, those who gestured at caregivers during the first week of life, gestured more frequently after oxytocin, than those who were not likely to gesture in the first week.

These results not only suggest that oxytocin may have a positive effect on social interaction among children with autism, but it can provide a model for studying early neurobiology and social behavior during development. Jerrold Meyer, behavioral endocrinologist of UMass Amherst calls these findings “exciting,” according to Science Codex. Further research on the breastfeeding hormone could help in developing new forms of treatment for developmental disorders of social behaviors.

In a similar 2013 study, the “love hormone” was found to help autistic children bond with others, although the effects did not last long. This suggests there should be considerations on whether this could be used as a treatment for social impairments. A single dose of the chemical improved brain responses to facial expressions and could be used rather as an add-on to the behavioral therapies for autistic people. The chemical one way or another, holds the key to possible autism treatment, since it plays a crucial role in bonding and trust.

Autism is seen in about one in 68 children, according to the Centers for Disease Control and Prevention, and affects individuals in a variety of ways. The developmental disorder is characterized by difficulties in social skills and communication. Currently there is neither a cure for autism nor an established treatment for the social problems brought on by the disorder.


Ferrari PF, Hamel AF, Meyer JS et al. Inhaled oxytocin increases positive social behaviors in newborn macaques. Proceedings of the National Academy of Sciences. 2014.

Bennett RHm Cordeaux C, Eilbott JA et al. Oxytocin enhances brain function in children with autism. Proceedings of the National Academy of Sciences. 2013.