Most people are reluctant to gamble if the potential losses outweigh the gains; something psychologists call loss aversion. Scientists think a part of the brain called the amygdala might play an important part in loss aversion and researchers at the California Institute of Technology studied two people who had suffered damage to this area. At the start of the experiment the participants, who also included twelve healthy controls, were given $50 to gamble on the toss of a coin. The ratio of what they would win to what they could lose was varied and when the risks outweighed the opportunities the healthy controls stopped gambling. However, the people with the damaged amygdalas carried on gambling whatever the risks confirming the theory that the amygdala does play a role in this process.
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