For centuries artists have tried to capture the essence of love, and now scientists may have found it in the brain. Known as oxytocin (from the Latin word for "quick birth"), the naturally occurring hormone is best known for controlling contractions during labor, but it also plays a key role in other fundamental human urges — including the desire to connect with others. "Somehow, the peptide increases trust, or alters the way individuals see each other," says Tom Insel, director of the National Institute for Mental Health.
Without oxytocin people would be far less inclined to seek social interaction, let alone fall in love and mate for life (or, as scientists call it, "pair bond"). The brain releases gobs of it during orgasm, mothers are awash in it during breastfeeding and, in clinical trials, a spritz of oxytocin has been shown to reduce anxiety, increase feelings of generosity and even ease the symptoms of shyness. Conversely, researchers are beginning to discover that low levels of the hormone — or the body's faulty response to it — may contribute to severe social dysfunctions like depression and autism.
Most previous research on oxytocin has focused on animals. (Prairie voles are famous for their oxytocin-inspired behavior: they're fiercely monogamous lovers and caring parents.) But more recently, scientists have begun to determine how oxytocin functions in the human brain — or, more specifically, how it malfunctions. Studies have shown that people with autism tend to have low levels of oxytocin, as well as hyperactivity in the amygdala, where most oxytocin receptors are located. The amygdala is also where memories are formed, and where our brains process and assign emotional meaning to sensory information — that is, where we turn perception (seeing someone smile) into "neuroception" (understanding the feeling of happiness that the smile reflects), according to Stephen Porges, a psychologist at the University of Illinois in Chicago. So, misfirings in the amygdala, in tandem with low oxytocin, may help explain why people with autism have trouble distinguishing between happy expressions and angry ones, making social interaction difficult and unpleasant.
Early studies of oxytocin's role in social interaction have yielded some interesting results. In a small 2006 experiment, Dr. Eric Hollander of New York's Mt. Sinai School of Medicine administered oxytocin and a placebo intravenously to 15 autistic adult patients; afterward, those who received oxytocin were better able to decipher emotions in tone of voice. Moreover, these improvements in social awareness lasted for nearly two weeks. In 2006, Hollander filed a patent for the use of oxytocin to treat symptoms of autism spectrum disorders; the request is still pending. Other investigators at Mt. Sinai have also found that oxytocin nasal sprays enhance autistic patients' ability to interpret facial expressions. Finally, in studies by Paul Zak, director of the Center for Neuroeconomics Studies in Claremont, Calif., small doses of inhaled oxytocin spray reduced anxiety and wariness of strangers in healthy volunteers; in one trial, the hormone made people feel more generous and trusting with their money.
For the oxytocin-deficient among us, the hormone is commercially available on the Internet in the form of a nasal spray — new mothers sometimes use it to trigger the release of breast milk (and nearly half of all women who give birth in the U.S. receive a synthetic version of the hormone, Pitocin, intravenously to induce labor). But some entrepreneurs are already touting oxytocin as a shyness cure. One website hawks a "trust elixir," an oxytocin-laced perfume that its manufacturers say will make its wearers seem more trustworthy to others — and vice versa.
There's no telling whether it works — products like these aren't classified as drugs, so they aren't evaluated by the FDA — but, at least in theory, it ought to make love or lust or trust bloom a little faster. That's not unlike the drug ecstasy, which triggers the release of serotonin, dopamine and oxytocin in the brain, and heightens users' feelings of trust and intimacy, even among complete strangers. Concerns that oxytocin might be similarly abused as a recreational drug seem unfounded, however, given that the hormone doesn't produce a high, says zoologist Sue Carter of the University of Illinois at Chicago, who pioneered oxytocin research in voles.
Oxytocin may be something of a wonder compound, spurring childbirth and creating love, but it's not exactly a performance enhancer and certainly not a cure-all — not for shyness or autism or any other social dysfunction. "The nervous system is not just oxytocin. There are many other hormones that might be just as important as oxytocin thathaven't been identified yet," Carter says. "A piece of social support is oxytocin. That doesn't mean that oxytocin alone equals social support."
But if a shot of oxytocin is what you want, there are other, more natural ways to boost the hormone's production. Massage, petting a dog, even eating food with a friend can trigger the chemical's release, says Zak. So can sensorimotor or "mind-body" therapies, like breathing exercises and yoga, which help people cope with their emotions by controlling their body's physical reaction to stress and fear. "We should look at other waysto juice the system without having to put two spoons of liquid up your nose every four hours," Zak says.
Preliminary findings may be intriguing, but most oxytocin researchers remain skeptical about its widespread clinical use. "If you feel safe and allow yourself to feel safe, you can learn, you can cooperate with others, you can build societies," says Carter. "Now does that mean we should runaround and spray everyone with oxytocin? I don't think so."
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