Stressed men take more risks, while stressed women play it safe, according to research published in the Journal PLoS One this week.
Nichole Lighthall, from the University of Southern California Davis School of Gerontology, asked volunteers to play a computer game designed to measure risk taking, called the Balloon Analogue Risk Task. In the game, participants pump up a balloon, winning a small amount of money per pump, until they stop and collect the cash or the balloon pops and they lose it all. The balloon would pop at random somewhere between 1 pump and 128 pumps, so for each pump the risk of losing increases and the potential gain decreases.
Then they did the same test again with a group of volunteers under stress. They stressed them out by making them hold their hands in ice cold water, and measured the levels of the stress hormone cortisol so they were certain this was a stressful situation.
Under stress, men take more risks and women are more risk averse, even though they take similar risks when not stressed. Women inflated the balloon an average of 32 times, over 30% less than men, who pumped an average of 48 times. This may correlate to risky behaviours in the real world, such as gambling, smoking, unsafe sex and illegal drug use.
So why should this be?
"Evolutionarily speaking, it's perhaps more beneficial for men to be aggressive in stressful, high-arousal situations when risk and reward are involved," said Dr Lighthall. "Applied to financial risk taking, it's akin to competition for territory or other valuable resources."
So men may have evolved to respond to stress with a flight or flight response – taking bigger risks, while women evolved a more conservative response, which could be beneficial as taking risks in pursuit of resources could “endanger the lives of dependent offspring.”