Testosterone may be bring forth thoughts of aggression, competitiveness, and sexual drive, but there may also be a softer side to the male hormone. Researchers at Erasmus University, in the Netherlands, have found that when those typical characteristics don’t come into play, testosterone could make people more social and willing to reciprocate positive behavior.

Researchers were interested in the relationship that testosterone had with social status. If it was associated with dominance, then it should also be associated with motivation to attain social status, they hypothesized.

“Testosterone may mediate competitive and potentially antisocial behavior when social challenges or threats need to be confronted and handled,” Maarten Boksem, of the Rotterdam School of Management at Erasmus, said in a statement. “But it can also induce pro-social behavior in the absence of these threats, when high status and good reputation are best served by positive behavior.”

For their study, the researchers set up a relatively simple financial experiment. Fifty-four women were given €20 (about $27), and told that they could keep some, or all, of the money or invest it with another person, the trustee, who would triple the amount given and then decide how they wanted to split the final amount. Of these 54 women, some drank a placebo solution and others drank a solution with added testosterone.

When the women were given the opportunity to be the investor, those who had taken testosterone were more likely to withhold some of their money, out of the belief that their trustee would not split their investment equally. On the other hand, those women who drank a placebo were more trusting with their investments, choosing to give about €3.20 more.

Next, the women were given €60 and told that they were the trustee. When they were given the task of splitting the money with the investor, the women who drank the testosterone solution tended to give more money than those who had the placebo solution. This suggests that they felt responsible for reciprocating the trust their investor had in their decision, the researchers said.

“While we expected the decrease in trust found in the first scenario, the increase in reciprocity was strong and robust,” Boksem said in the statement. “Testosterone had a more pronounced effect on pro-social behavior than on antisocial behavior.”

For women who have sufficient estrogen levels, testosterone might not only promote pro-sociability in non-competitive situations, but it can also increase sex drive, especially among those who have had surgically induced menopause or are postmenopausal and taking estrogen therapy, according to the Mayo Clinic.

Source: Boksem M, Mehta P, Son V, et al. Testosterone Inhibits Trust but Promotes Reciprocity. Psychological Science. 2013.