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Inhalation of Childbirth Hormone Bolsters Trust

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Inhalation of Childbirth Hormone Bolsters Trust

Inhalation of Childbirth Hormone Bolsters Trust

Inhalation of Childbirth Hormone Bolsters Trust

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  • <iframe src="" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
  • Transcript

Researchers say people are more likely to trust others if they inhale a chemical called oxytocin. In an experiment, volunteers who inhaled oxytocin, a hormone involved in childbirth, were far more likely than to trust someone else with their money than people not exposed to the hormone.


Many people don't believe the media, but trust me, this story is true. Researchers have found that a hormone involved in childbirth also seem to help people trust one another. NPR's Jon Hamilton has more.

JON HAMILTON reporting:

When doctors want to speed up childbirth, they sometimes give women a hormone called oxytocin, or pitocin. But researchers also know your brain also makes this hormone when you're with someone you trust. Brain researcher Paul Zak wondered what would happen if he gave people an extra dose of oxytocin. The experiment involved money. He and some Swiss colleagues gave volunteers a small sum and told them to sit in a booth.

Mr. PAUL ZAK (Researcher): And we walked over and gave them two puffs of this--of drug in each nostril, either drug or placebo, and we didn't know which they were getting, nor did they.

HAMILTON: Then the volunteers sat down at computers. They got a message saying that if they gave, say, $10 to an anonymous partner, the partner would get an extra $30. The suggestion was that by cooperating, they could both make money. But Zak, who's at Claremont Graduate University in California, says it was a tough decision.

Mr. ZAK: You could only send a signal of trust to somebody by making a sacrifice, by actually taking money out of your account, and whether that person will reciprocate and be trustworthy is unknown. There's no way to find out who that person is. There's no way to talk to them.

HAMILTON: It turned out that people who got oxytocin were more likely to trust someone else with their money.

Mr. ZAK: We've identified what could be called a physiologic signature for empathy. If we change underlying oxytocin levels, we indeed could change your level of trust.

HAMILTON: Zak say's that's remarkable, especially in an experiment where people's only contact was through a machine.

Mr. ZAK: They don't see the other person. They don't know who they are, and still this hormone motivates them to be socially engaged with other people.

HAMILTON: Or maybe they were just more willing to take a risk, so Zak had them play the game again. This time their anonymous partner was a computer, not a person, and this time oxytocin didn't make a difference. Those studies appear in this week's issue of the journal Nature.

So should we expect a trust perfume? Well, probably not.

Mr. ANTONIO DAMASIO (University of Iowa): It would be a mistake to say oxytocin equals trust.

HAMILTON: Antonio Damasio of the University of Iowa says trust is more than just a chemical reaction.

Mr. DAMASIO: Trust is something very complex and it is something that is cognitive. You know, it has to do with our mind making judgments. But, of course, when we make those judgments, inevitably we also generate emotion and feeling in relation to those judgments.

HAMILTON: Damasio says it's the combination of reason and emotion that's allowed people to create societies based on trust, and he speculates that politicians and marketers have already learned what to say to get our brains to churn out oxytocin.

Mr. DAMASIO: How do we know that the effects of advertisement and marketing are not produced precisely by the natural release of such a substance into our brains? So maybe we have, in fact, been using it all along without knowing that we have been using it specifically.

HAMILTON: Someday, Damasio says, someone may figure out a way to use oxytocin to win false trust. But the study suggests that won't be easy. Once the brain is flooded with its own oxytocin, adding an extra dose doesn't seem to make us any more trusting.

Jon Hamilton, NPR News.

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