In recent years, the hormone oxytocin has gained notoriety as an influence on various aspects of social behavior. A new study attempts to dispel myths and scientifically document the beneficial effects of the hormone.

According to background information, prior research has associated increased levels of oxytocin with greater caring, generosity, and trust.

However, researchers wanted to know if oxytocin increases people’s trust in just anybody or if it acts more selectively.

Psychological scientist Moïra Mikolajczak from the Université catholique de Louvain (Belgium) and her colleagues investigated just how trusting oxytocin can make us. In this experiment, volunteers received either a placebo or oxytocin nasal spray.

Then, they played a trust game in which they received a certain amount of money which they could share with a partner (any amount shared with the partner would then triple). The partner then decides what to do the money—they can keep it all for themselves or split the amount with the giver.

If the volunteer is trusting, they will share more money with their partner (in the hopes of having some of it returned to them) than volunteers who are not as trusting. The participants played the trust game against a computer and virtual partners (which were supposedly in another room), some of whom appeared reliable (they seemed likely to share the money with the participants) and some of whom appeared unreliable (they seemed likely to keep the money for themselves).

The results, reported in Psychological Science, a journal of the Association for Psychological Science, showed that volunteers who received the oxytocin nasal spray were more trusting of the computer and the reliable partners—that is, they offered more money to the computer and the reliable partner than did volunteers who received the placebo nasal spray.

However, oxytocin did not have an effect when it came to sharing with a seemingly unreliable partner—the volunteers were not generous toward a potentially unreliable partner, regardless of which nasal spray they received.

These findings suggest that OT fosters trust, but not gullibility: Oxytocin may make individuals more trusting, but only in certain situations.

The authors conclude that “oxytocin is not the magical ‘trust elixir’ described in the news, on the Internet, or even by some influential researchers.”

Source: Association for Psychological Science