High levels of testosterone can affect people’s willingness to cooperate – according to research published on the Proceedings of the Royal Society B.
Too much testosterone may mean that we prefer to make all decisions ourselves, even when it is just asking for cooperation. This was proven by the experiments conducted by Nicholas Wright from the University of London and his team on 34 women. After a dose of testosterone, they became less cooperative, although it was in their best interest.
Testosterone is the male sex hormone produced in the testes. In small concentrations, it can also be found in the bodies of women, in whom it is produced by the adrenal cortex, ovaries and placenta. The influence of this hormone on the willingness to cooperate was studied in women, because in men additional doses of testosterone inhibit its natural production in the body.
Wright and his team studied 17 pairs of women who did not know each other before. On the first day, everyone was given a testosterone supplement, on the second (after a week off) – identical-looking placebo. During the experiments, pairs of women were seated in one room in front of two monitors, which displayed identical pictures. Ladies were to choose one with a contrasting pattern that is difficult to recognize. If their choices were in agreement, the experiment was terminated. However, if they were different – the women were to come to an understanding and make a joint decision.
Couples taking placebo did much better than couples on hormones to achieve a joint result. Higher testosterone levels were associated with self-centered behavior and with decision-making in which subjects favored their own choices over those of their mates – even if they were wrong, Wright reports.
Excess testosterone can blind us to the opinions of others – he adds. – This is important especially when we are dealing with a dominant person who insists on his opinion, while he is sitting, for example, on a jury.
The study suggests that testosterone is uncooperative and makes people more egocentric. More generally, the concentration of these hormones can negatively affect the willingness to cooperate.
It is widely known how much the balance between the ability to cooperate and independence means, as well as the ability to judge when to use each of these tactics. Sometimes joining forces is the best way to achieve a goal – that’s why lions and hyenas hunt in groups, and humans work together on the field, in the laboratory, or on the battlefield. Sometimes, however, in order to achieve your goal, it is worth breaking ranks.
The ability to balance these extremes is largely due to science and experience. However, some impulses are deeply entrenched. Scientists studying the biological basis of collective decision-making have revealed, for example, that oxytocin, a hormone naturally present in our bodies, promotes cooperation. Testosterone, in turn, promotes antisocial and risk-taking behavior and a certain type of aggression that guarantees emotions to sports fans or stock brokers.