Women who receive a boost of the potent sex hormone act more generously than women on a placebo, a new study finds. But the hormone’s reputation seemed to precede itself. Those who suspected they had received bona fide testosterone acted more selfishly than those who believed they got the bogus treatment, no matter what they actually received.
This platitude may be true in some situations, but not all. The hormone’s real role is to push men and women to seek higher status, says Fehr. His team tested this hypothesis in women because previous research had established for women how long an external dose of the hormone remains in the body.
They asked 121 women given testosterone or a placebo to play a simple game in which cooperation is paramount. Called the ultimatum game, one participant is given $10 but must offer some of it to another woman. If the second woman rejects the offer, the first loses her money.
If testosterone plays a role in status-seeking, participants given the hormone should fear rejection more than others and so should make more generous offers, Fehr says.
That’s precisely what the team found – but only after accounting for people’s hunches about whether they had received testosterone or a placebo. Women on the placebo tended to offer $3.40, while those given the hormone tendered an average of $3.90.
Those who falsely believed they were on testosterone, however, offered about $1 less than women who believed they had taken the placebo.
When probed on their beliefs about testosterone, participants tended to buy into conventional wisdom, saying, “Oh, testosterone would make me more egotistic, more risk-taking and more aggressive,” Fehr says.
Such bias could explain the discrepancy between Fehr’s study and another study presented at an October meeting. A team led by Paul Zak and Karen Redwine of Claremont Graduate University in California found that testosterone makes college-age men – those in their early 20s – act more greedily when they played a similar ultimatum game. But these researchers did not probe their participants’ beliefs about testosterone.
Moreover, van Honk thinks the study shows that testosterone’s reputation as an antisocial agent is wrong and that hormones can have different effects on behavior depending on the context. “It shows, in my opinion, that you cannot talk about good and bad hormones,” he says.
Journal reference: Nature, DOI: 10.1038/nature08711
Filed under: Education Industrial Complex, Information Tagged: | Claremont Graduate University, Ernst Fehr, Jack van Honk, Karen Redwine, Paul Zak, testosterone, University of Zurich, Utrecht University