07.02.2007 - Biology
Researchers find human pheromone
Californian researchers identified a human pheromone: If women smell a certain decomposition product of testosteron called androstadienon, their mood improves and they react slightly arroused. This can be seen in their hormonal balance, researchers discovered. They also confirm the suspicion that the so-called androstadienon which is evaporated by men sweating can have the effect of a pheromone. Pheromones are fragrances which help creatures to communicate on a biochemical level. Up until now it was disputed if humans even react to pheromones.
Claire Wyart and her colleagues made 21 young experimentees take a whiff of a small amount of pure androstadienon or a similarly smelling control substance likewise. The scientists recorded body functions like breathing, blood pressure and heart rate. They asked the experiementees about their mood and identified the concentration of cortisol – a classical stress hormone – in their saliva. Experimentees smelling androstadienon felt elated and aroused which was measured by a higher increase of the cortisol concentration in their saliva.
Nevertheless, researchers weren't able to determine if the androstadienon was able to influence the cortisol concentration directly or if this was merely the result of an uplifted mood which then increased this concentration. They also point out that sweat is a very complex substance and androstadienon doesn't necessarily have to be the only provided pheromone in this substance.
It has been known for a while that animals communicate via fragrances. They use so-called pheromones for the purpose of sexual attraction, feature of distinction, emergency signal or to mark a designated area. There were also hints that humans react to those fragrances, too – just as those found in the sweat of the preferred gender. Nevertheless it was never determined which part of the sweat substance has pheromone qualities. Wyart and her colleagues were only able to show undisputedly that androstadienon effects humans like a pheromone. The smell has a measurable effect on the human body functions.
Claire Wyart (University of California, Berkeley) et al.: Journal of Neuroscience, Bd. 27, P. 1261
ddp/wissenschaft.de – Fabio Bergamin