If you want to know what’s going on in your brain this evening when you experience love, you first have to define your terms. Do you mean falling in love or being in love? Both are like a drug. If you’ve ever felt euphoric and dizzy after a promising date, you know that falling in love mimics the body’s response to a recreational drug. However, not to hit Cupid with a bag of poo or anything, but being in love is very different—more like waking up two weeks later in a pile of Cheetos bags with the dawning comprehension of addiction.
That’s because falling in love depends in part on good old dopamine—the brain’s reward chemical that is mimicked by opioids like heroin. Love, like heroin, creates dopamine release in the brain. Not only does this dopamine make you literally a bit dopy, blocking pain and inducing pleasure, but the pleasure of dopamine release makes you do things that lead to more pleasure. The dopamine in your brain after a good first date helps to ensure there is a second date.
Then you also get some oxytocin. No, this isn’t the widely abused prescription drug OxyContin or the equally abused oxycodone, but a naturally occurring neurotransmitter that facilitates the process of human bonding. Actually, oxytocin doesn’t only create human bonding; it’s been shown to create the mom-pup bond in lab mice. A nasal spray of oxytocin makes people in experiments more cooperative. And, just as it makes you bond with people you see as friends, allies or lovers, oxytocin also makes you exclude people you see as outsiders—meaning that a squirt of oxytocin while falling in love helps you grow eyes for your loved one while blinkering you to other options.
During sex, oxytocin is joined by vasopressin, a hormone involved in the body’s regulation of water retention and vasodilation. Research with prairie voles shows that vasopressin might be what creates the bonding experience of sex—with vasopressin, voles bond after mating; with vasopressin blocked, voles leave it at a one-night stand. Here’s a cool part: when researchers introduced vasopressin to pairs of prairie voles, they bonded even without mating. At least in prairie voles, it’s a chemical cocktail and not a whole lot more that creates the bonded experience of love.
And gosh darn if we can’t see the same thing in humans—the better your brain is at using oxytocin and vasopressin, the more likely you are to be in a bonded relationship. Really: your brain cells have receptors that are designed to trap these hormones, and there’s some evidence that people with less oxytocin and vasopressin receptors are more likely to divorce and more likely to have lower relationship satisfaction.
But that’s not the end of it. Like a molly pusher who cuts MDM with all sorts of chemicals meant to keep pests out of your garage, love mixes even more chemicals into your poor, besotted brain. One of these is norepinephrine, which makes your heart go pitter-pat. Norepinephrine, released during the elation of love, is part of the body’s fight-or-flight response, and it increases your ability to skip through fields of tulips with your new mate.
Finally, there’s serotonin. “Love lowers serotonin levels, which is common in people with obsessive-compulsive disorders,” says Mary Lynn, DO, codirector of the Loyola Sexual Wellness Clinic. “This may explain why we concentrate on little other than our partner during the early stages of a relationship.”
So you’ve got dopamine, which makes you stoned; oxytocin, which makes you dependent; norepinephrine, which makes you tweak; and serotonin, which makes you obsess. Over time, you become unable to exist without this stew of neurotransmitters. The longer you are in a relationship, the more your brain becomes used to these chemicals, and you reset your baseline in a way that makes you need them. The comparison with addiction is so strong that when Rutgers researcher Helen Fisher showed freshmen who had recently broken up with a boyfriend or girlfriend a picture of their ex, she saw the same areas of the brain activated as in drug cravings.
It makes sense. Our brains didn’t evolve to feel pleasure in response to drugs; drugs are simply an artificial way to hijack the pleasure system that was designed for another purpose, which is to help you feel love and bonding. To your brain, love is a drug and drugs are love. Put that in your pipe and smoke it.
Short of searching Amazon for legitimate dealers of oxytocin nasal spray (don’t waste your time) or putting your PhD to use by genetically engineering your way to increased serotonin release, you’ll have to come by the brain chemicals of love the old-fashioned way: by experiencing love. If love is hard to come by, physical contact will do it. Even platonic hugging creates oxytocin release, and some researchers believe that people who crave human contact after isolation are experiencing a sort of oxytocin withdrawal. And a 2007 article in the Journal of Psychiatry and Neuroscience recommends bright light to create a serotonin release similar to being in love. You thought “basking in the love” of your partner was only a metaphor? Turns out to be a little more literal than that. If you’re starved for love and human contact, you can get a hint of it by getting out into the sunlight.