From Ergo Log
They’re a pain on bodybuilding forums and message boards – aggressive posters who react way out of line to other visitors. Researchers at the University of Utrecht performed an experiment in which they showed how this kind of behaviour can arise. It’s all to do with a raised testosterone level.
The Utrecht researchers did a series of experiments with sixteen healthy young women aged between 19 and 26. They gave their subjects a drink of five millilitres of water which contained 0.5 milligrams of testosterone, five milligrams of cyclodextrine and five milligrams of alcohol. A quarter of an hour after drinking the mixture the women’s testosterone level rose and remained for about an hour at a level that is normal in men. One and a half hours after intake the testosterone level had returned to the old level.
The psychological effects of a testosterone supplement occur a bit later. Which is why the Utrecht researchers did their experiments four hours after the women had taken the testosterone supplement. A few days later the researchers repeated the experiments, but after giving the women a placebo.
The researchers got the women to look at actors’ faces. The actors showed increasingly strong emotions in a series of photos. In the example below an actor’s face shows an increasing amount of anger.
The women were shown photo series of actors expressing disgust, fear, happiness, sadness and surprise. The women had to indicate when they recognised the feelings being expressed, and say when they thought a face had an angry expression, or fearful, or sad.
The table below shows when the women recognised emotions in a series of photos.
For some emotions – happiness, sadness and surprise – it made no difference whether the women had taken testosterone or not. But testosterone supplementation did interfere with perception of anger, fear and disgust. These feelings are socially important. If you incite these feelings in others you are up to something that is socially unacceptable: you’re breaking rules. You are making a nuisance of yourself and you’re isolating yourself from the rest of humanity.
Testosterone supplementation blocks perception of these feelings. Before you know it you’ll be the only one left on the message board, and you’ll be posting with a handful of mates who happen to share the same IP address.
The researchers put it in more abstract terms. “These data suggest a possible psychobiological mechanism whereby testosterone predisposes individuals to antisocial behavior.”
Psychol Sci. 2007 Aug;18(8):663-7.