(A Valentine’s primer on the biology and psychology of love from Shenandoah University faculty.)
Why do people fall in love? Well, it’s about far more than romantic walks on the beach or fodder for songs and stories or Valentine’s Day. Love, it seems, combines chemical reactions and the need for survival. It also makes us feel great. There’s an old Roxy Music song called “Love Is The Drug,” which is truer than you may realize.
Let Shenandoah University Assistant Professor of Biology Elizabeth L. Cantwell, Ph.D., and Associate Professor of Psychology Scott P. King, Ph.D., fill you in on how love works, according to our bodies and our minds.
The Biology and Psychology of Love
From Dr. Cantwell:
From a biological standpoint, love arises from a series of biochemical reactions in the brain. There are three different phases.
Phase 1: Lust
Our gonads produce the hormones testosterone and estrogen. These hormones give us our male and female genders, keep our reproductive systems healthy and active, and trigger libido. Libido is also called “sex drive” because it drives us to seek sexual fulfillment.
Phase 2: Attraction
Attraction involves a variety of chemicals:
Epinephrine, which is released during stressful situations, is also released when you are attracted to someone. It is responsible for some telltale symptoms of attraction, including a racing heart, sweaty palms, dry mouth and restlessness. Adrenaline also alters blood flow around the body, including decreasing blood flow to the digestive system, which you perceive as butterflies in your stomach!
Dopamine release is increased in those who are newly in love. Dopamine activates desire and reward centers in the brain and increases your perception of pleasure.
Serotonin typically activates your brain’s limbic system, which is involved in memory and emotion, as well as your frontal lobe, which is responsible for planning and impulse control. Serotonin release is decreased in people who are newly in love (and also in people with Obsessive Compulsive Disorder!). This is why those who are newly attached can’t seem to think about anything other than their new love interest.
Collectively, these chemical responses encourage new couples to stay together, and increase their willingness to explain away each other’s faults.
Phase 3: Attachment
There are two hormones produced in the hypothalamus of the brain that make couples want to stay together:
Oxytocin is also known as the “cuddle hormone.” It is released during orgasm, and makes couples feel more attached to each other after sex. Therefore, the more sex a couple has, the closer their bond is likely to be. Incidentally, oxytocin is also released during childbirth and breastfeeding, which is why mothers also tend to feel a strong bond with their children.
Vasopressin, which is primarily responsible for regulating blood pressure and water balance in the body, also seems to strengthen loving bonds. How does it happen? We don’t really know… but studies in animals have shown that if you block vasopressin release, a bonded pair are less likely to stay together.
And, the psychology of love ties into its biology, according to Dr. King, in his answer to the question: “Why do people fall in love?”
My short, science-based answer for why people fall in love is that it helps us survive, both as individuals and as a species! To elaborate…
- The good feeling of being in love helps us stay committed in our intimate relationships
- Being in an intimate relationship increases our own chances of survival (through support and protection by partner), and reproduction, and the more chances we have of survival and reproduction, the greater the chances are that our genes will be passed on to the next generation, meaning that humans will stay alive on this planet
- Our brain likes the feeling of being love. The actual sensation of falling in love comes from the release of dopamine in ventral tegmental region of the brain. Dopamine is the same neurotransmitter released when we sense reward or completion of a goal (and the same pleasure centers activate when falling in love as when we’re on heroin or cocaine!)
Interested in hearing more from King and Cantwell and their colleagues?
Featured Photo Credit: Lee Howguar via Compfight cc