Oxytocin is a neurotransmitter and hormone. Many of you are probably familiar with it as it stimulates milk flow in breast feeding women and a synthetic version of it is sometimes used to induce labor. It is also released when hugging, touching and having an orgasm.

But did you know it was also involved with whether or not you trust a stranger?

Some amount of trust is necessary for a complex society to function. A long time ago, people lived in small groups where everyone knew each other. But now most of us are surrounded by strangers everyday. If we don’t have a least some trust in the people we interact with it would be difficult to accomplish anything.

In fact, in recent research by Paul Zak it was found that countries with higher levels of trust tend to be wealthier than those with lower levels of trust.

Additional research by Zak showed that when men feel distrusted they release more dihydrotestosterone (a derivative of testosterone). When men have higher levels of this hormone they tend to display more aggressive behaviors.

Women did not show this same response to being distrusted.

What do you think? Only more research will tell us for certain how much of our ability to trust each other is related to levels of oxytocin or other hormones. Meanwhile do you think that women seem to be less aggressive than men?

Read more about Paul Zak’s research at Scientific American: The Neurobiology of Trust. To learn more about oxytocin I recommend Susan Kuchinskas blog, Hug the Monkey and Wikipedia.