Testosterone reduces trust, study says
Small doses of the male sex hormone testosterone can make people less trusting of strangers, but the effect only seems to be true for the more trusting members of society, scientists have found.
Testosterone is produced by both sexes, although in much smaller quantities in women, and has been linked with aggression and competitive behaviour.
The researchers found that when testosterone is administered as a small, one-off dose to female volunteers, their sense of trust towards strangers changes, but only if the women tend to be trusting in the first place.
Jack van Honk of the University of Cape Town in South Africa said the findings suggested that testosterone generated mistrust in more gullible individuals as a way of protecting them against the deceitful behaviour of a competitive world.
He suggested that testosterone may work in opposition to the "love" hormone oxytocin, which is produced for instance in women during childbirth and promotes social bonding and trust between individuals.
The study, published in the journal Proceedings of the National Academy of Sciences, tested a panel of 24 young women for how trusting they felt towards a photographic gallery of strangers. They were then each given a small dose of testosterone under the tongue and asked to re-evaluate the photographic gallery.
The women who started out more trusting of strangers became significantly less trusting after taking the single shot of low-dose testosterone. No significant effect was seen in the women who were less trusting to begin with.
"We find the effect in socially naive people, those who are easily deceived by others. Maybe the hormone could help when the condition is pathological or damaging to the person," Dr van Honk said. Trust was crucial to the development of the earliest human societies where co-operation between unrelated individuals led to a better chance of survival. But this trust had to be counterbalanced with an awareness of possible cheating, he added.
- 1 Tunisia hotel attack: Locals form 'human shield' to protect hotel from gunman Seifeddine Rezgui
- 2 David Cameron refers to 83-year-old Labour MP Dennis Skinner as 'Jurassic Park'
- 3 Alton Towers Air breaks down: 80 people stuck on broken down Monorail during heatwave
- 4 German ethics council calls for incest between siblings to be legalised by Government
- 5 Alwaleed bin Talal: Saudi Prince to donate entire $32bn fortune to charity
Tunisia hotel attack: Locals form 'human shield' to protect hotel from gunman Seifeddine Rezgui
The map showing the most dangerous tourist destinations in Europe, according to the Foreign Office
German ethics council calls for incest between siblings to be legalised by Government
Alwaleed bin Talal: Saudi Prince to donate entire $32bn fortune to charity
Forget little green men – aliens will look like humans, says Cambridge University evolution expert
The moment a Queen's Guard soldier lost it and drew his gun at annoying tourist
Greece crisis: IMF was pushed around by Angela Merkel and Nicholas Sarkozy – and now it is being humiliated
Greece crisis: The wider lesson is that it’s time to abandon this failed experiment in currencies
'I wish the BBC would stop calling it Islamic State' – David Cameron unleashes frustration at broadcaster
Girl, 7, stares down hate preacher at Ohio festival with pro-LGBT rainbow flag gesture
They are neither a 'state' nor 'Islamic': Why we shouldn't call them Isis, Isil or IS
£35000 - £40000 per annum: Recruitment Genius: Are you familiar with the sayin...
£6 - £8 per hour: Recruitment Genius: This care organisation take pride in del...
£6 - £7 per hour: Recruitment Genius: This care organisation take pride in del...
£18000 - £25000 per annum: Recruitment Genius: A fantastic opportunity has ari...