Oxytocin

Oxytocin is a hormone produced in the section of the brain known as the hypothalamus. In popular culture it has gained recognition under a variety of monikers: "the social hormone," "the love hormone," "the intimacy drug," and so on. This is because oxytocin's primary effects appear to be the enhancement of empathy and of deep emotional bonds (though it may also enhance negative associations, depending on environmental factors). It is particularly associated with childbirth and breastfeeding as well as the development of trust or romantic affiliation between adults. A number of studies have also suggested that oxytocin may play a significant role in human sexual arousal, orgasm, and even fertilization. The evolutionary advantages that social bonding, affection, and even love may offer are believed to support larger populations, which are more likely to survive.

Brief History

Scientists have been studying oxytocin since the early part of the twentieth century. Its existence was first identified in 1906, though it was not named and distinguished from the related hormone vasopressin until the late 1920s. Biochemist Vincent du Vigneaud studied oxytocin in the 1950s, earning the 1955 Nobel Prize in chemistry for identifying its amino acid makeup and making it the first polypeptide hormone to be synthesized by scientists.

The name "oxytocin" is derived from Greek and means "quick birth," a reference to the fact that the body produces increased amounts of oxytocin when the cervix dilates during childbirth. Oxytocin produces effects in the brain and in the rest of the body, through its secretion from the pituitary gland. For example, oxytocin is part of the biochemical process responsible for the letdown effect, which occurs when an infant sucks at the mother's nipple, producing nerve impulses that are communicated to the hypothalamus in the mother's brain, which then causes the pituitary gland to begin producing oxytocin. In other words, the very action of an infant nursing causes the production of oxytocin, and the bonding enhancement effects of oxytocin on the mother encourage her to continue nursing for as long as the infant is hungry—another clear evolutionary advantage, as it avoids the problem of undernourished babies of mothers who might otherwise curtail nursing. It is also thought that the oxytocin produced during nursing stimulates contractions of the uterus that help the mother's womb to heal the location at which the placenta was attached during pregnancy.

Oxytocin also plays a role in mother-child bonding during nursing and beyond. Studies have shown mothers with higher levels of the hormone are more likely to act in ways that promote bonding, such as cuddling. Similar effects have also been demonstrated in males (with vasopressin also playing a role). Other studies have suggested oxytocin has effects on other aspects of social bonding, including memory and association and general perceptions of people in or outside one's social group.

Another line of research, further distinct from that involving childbirth and nursing, has to do with oxytocin's ability to assist the body in recovering from injuries it has suffered. Since time immemorial, folk wisdom has asserted that people are better able to overcome sickness and injury when they are attended by people with whom they share an affectional bond. This can even extend to animals, as indicated by the frequent use of "therapy dogs" to help patients cope with their illnesses by offering comfort and companionship. Scientists now believe there is evidence to support the observation that some types of wounds appear to heal more quickly and more completely when oxytocin is produced by the patient. This suggests a direct connection between the presence of supportive social bonds and improved patient outcomes, because having loved ones nearby during treatment causes the patient's body to produce greater amounts of oxytocin, which in turn augment the body's ability to heal itself.

Applications

Scientists continued to conduct research into oxytocin's physical and psychological roles. Although these processes are still not fully understood, the hormone has been used medically. Most notably, in synthetic form it has applications as a drug in the birth process, as it can help begin or strengthen contractions. It does come with potential side effects such as bleeding, nausea, and rapid heartbeat. If given too quickly, it can cause uterine damage. Oxytocin may also be used in cases of pregnancy termination or miscarriage.

Some research into the effects of oxytocin on social behavior and emotions has raised fears about how it might be manipulated, though skeptics view these concerns as little more than paranoid delusions arising from overly active imaginations. Because part of the effect produced by oxytocin is increased trust and bonding, there may also be a tendency for persons receiving high doses of the substance to have their critical faculties partially or even wholly impaired. The fear is that this could manifest itself by causing those receiving the drug to become more susceptible to the power of suggestion, meaning that it might be easier for them to be persuaded to act against their own interests. This has given rise to nightmare scenarios in which oxytocin or a related compound is administered to a population in order to help convince its citizens to vote for a particular candidate, buy a certain product, or similarly comply with nefarious suggestions. It has even been suggested that oxytocin may have potential military applications, such as helping to subdue hostile populations as a form of biologically enhanced psychological warfare. There is an element of science fiction surrounding some of the concerns, but not yet enough to warrant their outright dismissal.

At the other end of the research spectrum, a growing number of doctors believe that oxytocin may offer a number of profoundly important benefits in the field of public health. One such benefit might be realized by those suffering from autism spectrum disorders. One aspect of autism common to many of those afflicted with the syndrome is a difficulty making connections with other people, or an impaired ability to understand or even take notice of the emotional states of others. Those with such disorders frequently fail to respond appropriately to social cues because they are either unaware of their meaning, or they fail to notice them altogether. Research has examined whether those with autism spectrum disorders might experience a greater ability to empathize with others if they were to receive increased doses of oxytocin. One small 2013 study on oxytocin nasal sprays in children showed the treatment generated more activity in the area of the brain linked to social interactions (though it showed no direct impact on the ability to identify emotions).

Similarly, there may be a host of related disorders worth exploring for treatment with oxytocin, such as social anxiety disorder and related anxiety-based syndromes. Some investigation has been done into the use of oxytocin to allay symptoms of borderline personality disorder (BPD). The disorder causes a number of social difficulties, including what is known as interpersonal hypersensitivity, which leads BPD sufferers to misinterpret positive or neutral social cues as indicative of others' negative opinions of or attitudes toward them. Researchers hope that an increased level of oxytocin might reduce this tendency, or at least help those with BPD to feel less stress after a negatively interpreted social interaction. The few studies that have been done on the topic have had mixed results, however. In general, further research is required before oxytocin can be touted as a treatment for any mental health issues, from autism spectrum disorder to addiction to stress.

Oxytocin may have beneficial uses outside of the mental health discipline as well. A 2017 study conducted in Germany with over 100 participants also found that oxytocin in combination with social norms tended to decrease xenophobic attitudes and encourage altruistic behavior toward immigrants and refugees. The researchers' conclusion was that if those with positive attitudes toward people from other cultures make their opinions public, they may influence the opinions of their friends, family, and neighbors through a combination of shifting social norms and the elevated oxytocin levels that accompany social interactions and shared activities. However, other studies have suggested that oxytocin can also enhance negative perceptions of people considered outside of one's social group.

While oxytocin sprays are mainly used in research contexts, they have also been sold as non-prescription drugs touting anti-stress and social life improvement benefits. However, such products are unregulated and their claims are unsupported by evidence. The lack of regulation means they may not even actually contain the hormone. As research into oxytocin continues, the main challenge scientists face is to discover ways in which people can benefit from the hormone in a more controlled, deliberate way, while finding ways to prevent the cynical and unethical misuse of the drug's properties.

Bibliography

Baron-Cohen, Simon, Helen Tager-Flusberg, and Michael V. Lombardo, editors. Understanding Other Minds: Perspectives from Developmental Social Neuroscience. 3rd ed., Oxford UP, 2013.

Breuning, Loretta Graziano. Habits of a Happy Brain: Retrain Your Brain to Boost Your Serotonin, Dopamine, Oxytocin, & Endorphin Levels. Adams Media, 2015.

Breuning, Loretta Graziano. Meet Your Happy Chemicals: Dopamine, Endorphin, Oxytocin, Serotonin. CreateSpace Independent Publishing Platform, 2012.

Choleris, Elena, Donald W. Pfaff, and Martin Kavaliers, editors. Oxytocin, Vasopressin, and Related Peptides in the Regulation of Behavior. Cambridge UP, 2013.

Fineberg, Sarah K., and David A. Ross. "Oxytocin and the Social Brain." Biological Psychiatry, vol. 81, no. 2, 2017, pp. e19–e21.

Fish, Stephanie, editor. "Brain Hormones." Endocrine Society, 24 Jan. 2022, www.endocrine.org/patient-engagement/endocrine-library/hormones-and-endocrine-function/brain-hormones. Accessed 29 Jan. 2025.

LeWine, Howard E. "Oxytocin: The Love Hormone." Harvard Health Publishing, Harvard Medical School, 13 June 2023, www.health.harvard.edu/mind-and-mood/oxytocin-the-love-hormone. Accessed 29 Jan. 2025.

MacGill, Markus. "What Is the Link Between Love and Oxytocin?" MedicalNewsToday, 4 Sept. 2017, www.medicalnewstoday.com/articles/275795.php. Accessed 29 Jan. 2025.

Marsh, Nina, et al. "Oxytocin-Enforced Norm Compliance Reduces Xenophobic Outgroup Rejection." PNAS, vol. 114, no. 35, 2017, pp. 9314–9319.

Mikulincer, Mario, and Phillip R. Shaver, editors. Mechanisms of Social Connection: From Brain to Group. American Psychological Association, 2014.

Moberg, Kerstin Uvnäs. The Hormone of Closeness: The Role of Oxytocin in Relationships. Pinter & Martin, 2013.

Stoller, K. P. Oxytocin: The Hormone of Healing and Hope. CreateSpace Independent Publishing Platform, 2012.

Takahashi, Toku, Irena Gribovskaja-Rupp, and Reji Babygirija. Physiology of Love: Role of Oxytocin in Human Relationships, Stress Response and Health. Nova Science Publishers, 2013.