Love on the Brain
When already half of February passed it’s nearly impossible to ignore the ostentatious entry of the month of love as stores fill with heart-shaped boxes, chocolates, and cute animal plushies. While Valentine’s Day focuses on romantic love, love also exists in many of our social, non-romantic relationships: between siblings, parents and children, and friends. But where does this emotion of “love” come from? What biologically allows us to form these complex, deep connections with others who are sometimes very different than we are?sychologists and neurobiologists are especially interested in these questions as they discover the physiological mechanisms behind the strong impulses and feelings associated with love. Current research suggests there are a collection of hormones and neurotransmitters that are intricately involved with feelings of love and the formation of lasting social relationships. In this article, we will focus on two of these love molecules: dopamine and oxytocin.
Hormones and Neurotransmitters
Hormones and neurotransmitters are examples of chemical messengers the body uses to relay information and control physiological mechanisms. What distinguishes these two messengers is the distance the molecule travels and the organ from which the message originates. Hormones are produced and excreted by endocrine glands and usually travel through the bloodstream to cell targets that are farther away in the body. Neurotransmitters are produced by neurons and typically travel very short distances (usually less than a micrometer) to other neurons or muscle cells.
In biology, you will rarely come across an enzyme, metabolite, or hormone that performs only one specific function. This remains true for many signaling molecules. Often a single hormone or neurotransmitter can have the potential to interact with many receptors and targets throughout the body. Dopamine, a neurotransmitter, is involved in motor control, attention, learning, and emotion processing. Oxytocin, a hormone created in the hypothalamus and released by the pituitary gland, stimulates lactation and contractions during labor. In men, oxytocin can influence the production of testosterone, another hormone. But how are dopamine and oxytocin involved with love?
Dopamine + Oxytocin = Love?
Researchers have investigated human and animal neurochemistry to detect signaling molecules associated with love, attraction, and attachment. Aside from their physiologic functions discussed earlier, dopamine and oxytocin have been identified as key contributors to the development of social bonds.
Specific neural circuits in the brain are involved with reward anticipation and processing. In these circuits, dopamine is one of the primary neurotransmitters responsible for the euphoria and excitement that accompanies reward. Motivation, focus, and goal-orientated behaviors are also associated with high concentrations of dopamine in the brain1. When we do things that we enjoy, like eating sweets, talking with a friend, or enjoying the aroma of an essential oil, the brain registers these experiences as “rewards” and floods the reward-orientated neural networks with dopamine.
Dopamine brings us feelings of pleasure and reinforces certain behaviors so that we seek rewards again in the future. It shouldn’t come as a surprise that surges of dopamine also accompany romantic attraction. The excitement and elation that come with the early throes of romantic love are in part due to the circulation of dopamine throughout neural reward pathways in the brain. Researchers have demonstrated this phenomenon by examining the brains of individuals while they view images of their romantic partners. Higher concentrations of dopamine were observed when participants viewed images of their romantic partners than when they viewed images of their friends2.
While dopamine is involved in the early, exciting, and passionate stages of our romantic relationships, oxytocin takes main stage in forming lifelong relationships. As mentioned earlier, oxytocin becomes especially important during labor and birth as it accelerates the rate of uterine contractions and stimulates the production of milk. In addition, oxytocin has been correlated with mother and child bonding during their first interactions after birth, facilitated by direct skin-to-skin contact. However, even outside of parental bonding contexts, oxytocin is often referred to as the “bonding” or “cuddle” hormone, as its release can be stimulated by many forms of physical touch, whether from a friendly hug or intimacy with a loved one. Feelings of safety, security, and contentedness are reinforced by the release of oxytocin as we interact with the people we care about3.
An unfortunate truth: many of the romantic or platonic relationships we engage in simply don’t last forever. As time passes and life becomes busier, social bonds that were once intensely satisfying can begin to fade. While many of these processes are normal and universally experienced the pain and heartache that accompany them is undeniable. “Love-sickness” isn’t a disease condition recognized by scientific or medical communities; however, research has suggested some possible antidotes for heartbreak. One review suggests the cannabinoid action of beta-caryophyllene, a major constituent of Copaiba and Black Pepperessential oils, may have a role in affecting dopamine activity.* Some dopamine-related neurons have CB2 receptors, a type of cannabinoid receptor. Because of the potential interaction between beta-caryophyllene with certain dopamine pathways, beta-caryophyllene may help with negative feelings associated with heartache4.
It’s no wonder why so many of us find fulfillment and happiness in our social and romantic relationships—our brains are hardwired to do so. Love that we feel for our friends, family, and romantic partners is perpetuated by many hormones and neurotransmitters. Dopamine and oxytocin play significant roles in attraction, attachment, and social trust. Other hormones, like serotonin, norepinephrine, vasopressin, cortisol, and endorphins, have also been associated with the complex web of emotions and thoughts that are encompassed by love.
The neurochemistry of love is complex, but your relationships don’t have to be. Spend this month thinking of ways you can show the people you care for how you feel about them. Acts of service, gifts, or words of affirmation can foster the release of dopamine and oxytocin in both you and your loved ones, further strengthening your biological and chemical bonds.