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Cambridge University Science Magazine
From Bernie Madoff to Tiger Woods, from Aeschylus to Shakespeare, many human scripts of tragedy and betrayal can be better understood in the context of oxytocin. Gestures of affection and compassion: a caress, promise or well-delivered financial commitment, will discharge oxytocin into the bloodstream. In 2005, Swiss researchers found that after individually delivering a squirt of oxytocin to subjects, the peptide hormone increased trust in an investment game, at once expanding both interaction and potential for betrayal.

Scientists at Utrecht University seem to have identified testosterone as the antidote to this excessive trust. They administered testosterone, in the form of a liquid drop under the tongue, to young women who were then asked to judge the trustworthiness of certain men's faces. Those under the influence of testosterone were significantly less likely to trust the faces.

Women already deemed to be less trusting, due to a natural inhibition to oxytocin in the placebo test, were hardly affected by the testosterone dosage, while the more trusting women had their attitudes change substantially. Testosterone thus seems to be, in the context of trustworthiness, a protective mechanism for women. It adaptively increases social vigilance and stigmatisation in trusting individuals to better protect their long-term interests.

This study comes on the heels of notable research into testosterone's effect on fair bargaining behaviour and the female libido. Folk wisdom has generalised findings from animal studies to conclude that testosterone is most likely responsible for increasing antisocial and aggressive human behaviour. While, research published in Nature in January demonstrates that a single dose of testosterone in women substantially reduces bargaining conflicts and increases the efficiency of social interactions. Testosterone is also known from other studies to enhance a woman's libido, as there is a peak production of the hormone in the period prior to ovulation.

Combined, this recent testosterone research demonstrates that, in women, high levels of the hormone elicits fair and efficient social behaviour, heightened skepticism about other individual's intentions, and increased sexual desire. From this, the Dutch researchers conclude that "the hormone seems to motivate for rational decision-making, social scrutiny and cleverness, the apparent tools for success in a modern society."

The research is published in the Proceedings of the National Acadamey of Science.

Written by Taylor Burns