UZH team shows social sensitivity of oxytocin levels

(CONNECT) A study led by Charlotte Debras and Adrian Jaeggi from the Institute of Evolutionary Medicine at UZH has found evidence that oxytocin, known as the cuddle or bonding hormone, has a more complex effect than previously assumed. Their study results show that the values increase not only in moments of closeness, but also in group competition, for example in team sports - but not for everyone.

This was investigated among the indigenous Tsimane population in the Bolivian Amazon region by organizing football tournaments there. The researchers assumed that oxytocin plays an important role in social cohesion.

When analyzing the results, two things were surprising: Firstly, the oxytocin level only increased in men, and even more so when the opposing team was not members of the Tsimane, but a clear us-versus-them. "This suggests that oxytocin reacts sensitively to the social significance of the opponent - both with familiar rivals and with clearly demarcated foreign groups," Jaeggi is quoted as saying. Debras assumes that women showed virtually no changes due to their higher initial values - many were breastfeeding. Secondly, for women, competition is more about reputation or support and less about physical competitions.

The study leaves open the question of whether the increase in oxytocin primarily strengthens team cohesion or promotes differentiation from opponents. "Cooperation can be a successful strategy in competition, and oxytocin seems to be central to this," says Jaeggi. However, "oxytocin has also been linked to group conflict in numerous animal species, from fish to chimpanzees. The results suggest that similar mechanisms also work in humans." ce/mm