It’s been called the cuddle hormone , the holiday hormone , the moral molecule , and more—but new research suggests that oxytocin needs some new nicknames. Like maybe the conformity hormone, or perhaps the America-Number-One! molecule.
Where does this many-monikered neuropeptide come from? Scientists first found it in mothers, whose bodies flood with oxytocin during childbirth and breastfeeding—which presumably helps Mom somehow decide that it’s better to care for a poopy, colicky infant than to chuck it out the nearest window. And, indeed, one study found a shot of oxytocin more rewarding to rat-mommies than a snort of cocaine. (Don't worry, Dads: You can get some of that oxytocin action , too.)
As time went on, researchers found oxytocin playing a role in all kinds of happy occasions, from social activities (recognizing faces at a party) to more intimate ones (achieving orgasm with someone you met at that party). Lab tests found that oxytocin made people more trusting , more generous , and more gregarious. Thus oxytocin seemed, for a little while, to deserve its glut of touchy-feely nicknames.
In the past few years, however, new research is finding that oxytocin doesn’t just bond us to mothers, lovers, and friends—it also seems to play a role in excluding others from that bond. (And perhaps, as one scientist has argued, wanting what other people have.) This just makes oxytocin more interesting—and it points to a fundamental, constantly recurring fact about human beings: Many of the same biological and psychological mechanisms that bond us together can also tear us apart. It all depends on the social and emotional context.
The research is ongoing, and scientists are still debating how their findings fit together. But here’s a round-up of recent discoveries about oxytocin, boiled down to five cuddly and not-so-cuddly ways it might shape your social life.
1. It keeps you loyal to your love — and leery of the rest.
Men are dogs, right? They just want one thing, huh? Well, not if they’re jacked up on oxytocin. In fact, if they’re already in a loving relationship, they can become downright unfriendly to the opposite sex, according to a 2012 study in the Journal of Neuroscience .
Fifty-seven hot-blooded, heterosexual German men sprayed either oxytocin or a placebo up their own noses—and were then sent, alone, into a small room with beautiful young woman holding a clipboard. The questions she asked were irrelevant; instead, these scientists were measuring how close the men stood to the temptress as the two talked. (Here’s a tip: When you walk into a lab, never trust an experimental psychologist—those people are liars ).
It turned out that if an oxytocin-snorting guy was already in a relationship, boyfriend actually kept his distance from his lovely interlocutor. Partnered guys who sniffed the placebo leaned in a little closer than their partners might have liked. The single guys, meanwhile, were probably too busy staring down her cleavage to hear the questions.
So oxytocin doesn’t simply make you all lovey-dovey, suggests this study. It also keeps you faithful to your partner — and wary of her rivals.
2. It makes us poor winners and sore losers.
Let’s say you’re playing a nice friendly game of poker. You like the people you’re playing with, you’re enjoying yourself. Until you start losing. The bastard on the other side of the table shows four of a kind or a full house every single time, and you can’t even get a pair. Damn him; he must be cheating. But then one hand later, you lay down a straight flush and take all his chips. Are you gracious? Hell, no. You light a cigar and gloat like a goat.
You might be surprised to hear that your posterior pituitary gland was probably secreting oxytocin through every step of that game, from the good feeling to the envy to the taunting. Quite a few studies have found that people dosed with oxytocin are more likely to spite their opponents when playing games of chance, which has led Andrew Kemp of the University of Sydney to argue that oxytocin plays a role in what psychologists call “approach-related” emotions—ones that have to do with wanting something from someone.
What about the friend who lost the game? You may have just lost that particular poker buddy—and again, oxytocin may play a role. If your friend is a mouse, anyway.
Researchers at Northwestern University put three groups of cute, gentle mice in a cage with another pack of crazy, aggressive ones. One of those three groups of mice had their oxytocin receptors removed. The other group had more receptors than usual. The third was normal.
All three groups were equally mauled by the psycho-mice, until the researchers rescued them. Their whiskers twitched, their pink noses happily wiggled—those mice thought they were safe.
But then, six hours later, scientists put the three groups back in the cage with the psycho-mice. (Remember, folks: Never trust an experimental psychologist .) Guess what? The oxytocin-free mice didn’t remember the mauling and didn’t know to run away, poor little guys. The other two groups scattered in fear.
The study , published in July by Nature Neuroscience , suggests that oxytocin strengthens social memories in the lateral septum, which has the highest oxytocin levels in the brains of both mice and humans. Yes, oxytocin is involved with attachment and social bonding, but that neural system can get tangled up in fear and anxiety—it gives us a visceral memory of those who have harmed us, as well as those who have cared for us.
The takeaway? If you beat the pants off your friends at poker and you want to play with them again, don’t gloat—but if you do, be sure to first remove their oxytocin receptors.