Man is often a creature of impulse, a trait that has many times led to his own downfall. However, beyond mere speculation, science has failed to prove the biological reason behind this impulsive behavior. A recent study has given evidence to suggest that hormonal changes during stressful situations can directly influence risk-taking behavior, but only in men.

Testosterone and cortisol are natural steroids present in both men and women, although in different concentrations. During stressful situations, levels of these hormones will increase, but their exact influence on our behavior has not been confirmed. In a study recently published in the online journal Scientific Reports, researchers from the Imperial College London measured the levels of these hormones in both men and women during real world-simulated stress-inducing situations.

To test whether hormone levels influenced human behavior in stressful situations, the team devised a mock asset trading game meant to increase stress levels and encourage risk-taking behaviors. Researchers measured testosterone and cortisol levels via saliva samples in a total of 142 volunteers, both male and female, before and after the experiments. The volunteers’ risk-taking behavior during the experiment was also noted.

Latinos Health reported that, for men, higher cortisol levels were directly correlated with increased risk-taking behavior. However, the female volunteers seemed indifferent to the hormone changes. This would suggest that men and women have different stress responses.

For a second experiment, 75 young men were purposely administered doses of either cortisol or testosterone before partaking in the mock asset game. Results were seen almost immediately, with average trade time dropping by seconds and the researchers observing a notable “atmosphere of irrational exuberance,” The Telegraph reported.

Although the conclusion on its own is interesting, the ultimate goal of the team is to use their findings to better understand our behavior in real world situations.

"Our view is that hormonal changes can help us understand traders' behavior, particularly during periods of financial instability," said Dr Carlos Cueva, one of the lead authors of the study, from the Department of Economics at the University of Alicante, Science Daily reported.

Overvaluations in asset markets is a constant problem that has arguably led to many damaging miscalculated trades, The Telegraph reported. Such information could be particularly useful for policymakers as they try to create a more stable financial institution. The team hopes to further build on their findings between hormone levels and aggressive behavior.

"We only looked at the acute effects of the hormones in the lab. It would be interesting to measure traders' hormone levels in the real world, and also to see what the longer term effects might be," said Dr. Ed Roberts, study author from Imperial College of London, as reported by Science Daily.

Source: Cueva C, Roberts RE, Spencer T, Rani N, et al. Cortisol and testosterone increase financial risk taking and may destabilize markets. Scientific Reports. 2015.