After doing some preliminary research, I’ve learned that oxytocin plays a role, not just in lovemaking, but in forming social bonds of many varieties. Oxytocin can be administered exogenously; however, we are fortunate enough that our bodies produce oxytocin naturally, and that we have receptors in which this social hormone can bind! (This point will be revisited later.)
To give you some background knowledge, oxytocin is a hormone produced by the hypothalamus and is stored and secreted by the posterior pituitary gland. Recall that the hypothalamus is a limbic system structure, thus influencing various emotional responses, along with its many other functions. Blood vessel connections between the hypothalamus and pituitary gland allow hypohthalamic hormones to control pituitary hormone secretion (Biology.about.com). The pituitary gland, on the other hand, is an endocrine organ that is divided into three lobes: anterior, intermediate, and posterior. It is often referred to as the “Master Gland” because it directs other organs and endocrine glands (Biology.about.com). Now, we will explore more closely the role oxytocin plays in the social world…of prairie voles.
It is known that researchers use animal models and conduct animal experiments to gain a better understanding of how the human body functions. More specifically, we are able to manipulate and observe animals in a way that we cannot easily (or ethically) do in humans. Prairie voles are among the 3 percent of mammals that establish “family” relationships the way people do (howstuffworks.com), but can neurobiology help us understand why? The answer is yes! Prairie voles not only release oxytocin and vasopressin while mating, but they also have the necessary receptors for these hormones in their brains. This point is essential because unlike prairie voles, montane voles experience the release of oxytocin, but not its effects. This is because montane voles do not have receptors for oxytocin (or vasopressin) in their brains, causing this nearly identical mammalian species to pursue social relationships in quite the opposite manner.
So what relevance does this all have for humans? Well, like the prairie voles, we too have receptors for oxytocin. In humans, this hormone is stimulated during sex, birth, and breast feeding, to name a few situations in which its presence is common. Some researchers suggest that breastfeeding helps mothers bond with their babies. The act of breastfeeding results in a massive rush of oxytocin in women’s brains (dailymail.co.uk). The surge of oxytocin enhances a mother’s feelings of trust, love and affection, as explained in the article: “This extra release of oxytocin creates much stronger links between nerve cells – creating a ‘positive-feedback’ loop, where the greater the concentration of the chemical, the faster it is produced” (dailymail.co.uk). No wonder oxytocin has been deemed the “love” hormone; not exclusively referring to romantic love.