There are tons of clichés to describe the feeling of falling in love, from butterflies in your stomach to your heart racing to the cover of a Harlequin romance novel.
As cheesy as they may sound, they’re accurate in that our bodies do physically change when we’re in love. These biological changes are more than intangible tingles. So, for the sake of science, we’re disbanding the poetic love clichés and giving you the skinny on the science behind love.
MRIs show that the caudate nucleus and ventral tegmental area of your brain lights up when you’re in the romantic phase of love. This is thanks to the release of the “love chemical” dopamine (we know it as the addictive substance that sugar, sleep, thirst and tobacco trigger).
We develop relationship patterns in childhood that can come back to haunt us as adults. We often relive the same conflicts over and over, but the most frustrating people can be a blessing in disguise. They can help us recognize and modify our patterns. We can grow and experience true happiness and love in a relationship when we finally resolve our childhood trauma through adult drama.
When you’re in love and nurture the relationship, your brain pumps out this feel-good chemical. This in turn drives reward-seeking behavior (craving), increasing the brain’s release of the euphoric hormone, serotonin.
The result? The better you feel, the more you want. Because the dopamine pathway increases with risk taking, we tend to seek what’s new and exciting.
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When in “romantic” love, dopamine and serotonin are high. Without your loved one, that lovesick feeling is no joke, it’s chemical! (This is the stuff love poems are made of.) Being lovesick makes serotonin levels drop 40 percent—to the level of people with obsessive-compulsive disorder. And being in love triggers the release of “happy chemicals,” explaining why we feel happy when we’re in a good relationship.
Unfortunately, we all develop a tolerance to dopamine over time. Our brain cells release the same amount, but the receptors turn inward; they don’t get the dopamine message. This is why relationships can lose some luster over the years.
One way to continue the chemical high is to try new (and exotic) behaviors to increase dopamine. This stimulates more receptors (the reason why new sex positions and sex in different rooms seem exciting).
Don’t worry, another hormone comes into play to keep you engaged in a loving relationship. Oxytocin is the powerful chemical that makes you feel intimacy and a sense of community. When researchers blocked oxytocin in prairie voles (animals that mate for life), they came out of their holes and moved on. No oxytocin, no intimacy, no lifelong love. Talking also increases oxytocin. Perhaps this explains why communication is so important in relationships.
This increase in oxytocin (and the entire symphony of brain chemicals that influence love) is a key reason why 99 percent of humans live in pair bonds. We’re not just talking about marriage, but any intimate relationship with a strong partner, including a significant other, parent, sibling, close friend or pet. (Women desire this community feeling more than men.)
From a survival standpoint, it’s important to live in communities—hence the evolution of these biochemicals.
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Nonetheless, after about four years of a relationship, the chemical tirade that keeps us together starts to recede. This timing isn’t a coincidence. At this point, any potential offspring wouldn’t be entirely dependent on the mother. This leaves her better able to provide for herself and children.
Fathers are more prone to leave without these chemical handcuffs. This is why relationships need to move from pure romance to a deeper level of connection, so you can create a fertile field for lifelong pair-bonding.