Worried about losing money? Neuroscientists say your amygdala is the culprit.
Researchers at the California Institute of Technology have linked the brain structure, made up of two almond-shaped clusters of tissue in the medial temporal lobes, to human economic behavior. Their work was published in a recent online issue of the Proceedings of the National Academy of Sciences.
The scientists conducted a simple economics task with participants, including two patients whose amygdalae had been destroyed by a rare genetic disease and people without such damage. The study participants were asked whether they would accept a series of economic gambles, such as a 50/50 gable to win or lose $20.
The participants with amygdala damage made risky choices much more often than those without damage, even when the patients were equals in age and educational level. And unlike the control group, the two participants with amygdala damage showed no aversion to monetary loss, which according to the researchers was a first for a study participant.
"Loss aversion has been observed in many economics studies, from monkeys trading tokens for food to people on high-stakes game shows," said Colin Camerer, a scientist and one of the study's authors. "But this is the first clear evidence of a special brain structure that is responsible for fear of such losses."
The amygdala was already known to register emotional reactions and is connected to conditions including depression, anxiety and autism.
The research was supported by the Gordon and Betty Moore Foundation, the Human Frontier Science Program, the Wellcome Trust, the National Institutes of Health, the Simons Foundation and a Global Center of Excellence grant from the Japanese government.