Financial market traders and keen gamblers take note. Scientists have found that a chemical in the region of the brain involved in sensory and reward systems is crucial to whether people simply brush off the pain of financial losses.
Scientists say the study points the way to the possible development of drugs to treat problem gamblers and sheds light on what may have been going on in the brains of Wall Street and City of London traders as the 2008 financial crisis took hold.
"Pathological gambling that happens at regular casinos is bad enough, but I think it's also happening a lot now at Casino Wall Street and Casino City of London," said Julio Licinio, editor of the Molecular Psychiatry journal which reviewed and published the brain study on Tuesday.
"We like to believe we all have free will and make whatever decisions we want to, but this shows it's not so easy," he said in a telephone interview. "Many people have a predisposure to make certain kinds of decisions."
For the study, a team of researchers led by Hidehiko Takahashi of the Kyoto University graduate school of medicine in Japan, scanned the brains of 19 healthy men with positron emission tomography (PET) scans after they had completed a gambling task.
The experiment showed that a neurotransmitter, or chemical messenger, called norepinephrine, or noradrenaline, is central to the response to losing money.
Those with low levels of norepinephrine transporters had higher levels of the chemical in a crucial part of their brain - leading them to be less aroused by and less sensitive to the pain of losing money, the researchers found.
People with higher levels of transporters and therefore lower levels of norepinephrine or noradrenaline have what is known as "loss aversion," where they have a more pronounced emotional response to losses compared to gains.
Loss aversion can vary widely between people, the researchers explained. While most people would only enter a two outcome gamble if it were possible to win more than they could lose, people with impaired decision making show reduced sensitivity to financial loss.
"This research uses sophisticated brain scanning to improve our understanding of the way that our appetite for risk is linked to the way that chemical messengers operate in the brain," said Derek Hill, a professor of medical imaging science at University College London who was not involved in the research but intrigued by its findings.
"It is quite preliminary work, but has many intriguing implications," he said, adding this sort of imaging could in future be used to help test drugs to treat people who indulge excessively in risky behavior.
Alexis Bailey, a lecturer in neuropharmacology at Britain's University of Surrey, said scientists now need to analyze known pathological gamblers to confirm whether they have higher levels of these brain chemical transporters than non-gamblers.
"Also there is a need to investigate if noradrenaline transporters are also increased in brain regions traditionally associated with decision making and emotional aspects of aversion such as the prefrontal cortex and amygdala," he said.