Researchers found a link between brain structure and tolerance risk.

The findings could be the first stable "biomarker" for financial risk attitudes, the University of Sydney reported. In a whole brain analysis the researchers found gray matter volume of a region of the right posterior parietal cortex predicted the individual risk of attitudes. Men and women who had higher gray matter volume in this region tended to exhibit less risk aversion.

"Individual risk attitudes are correlated with the grey matter volume in the posterior parietal cortex suggesting existence of an anatomical biomarker for financial risk-attitude," said Agnieszka Tymula, an economist at the University of Sydney.

The findings suggest tolerance of risk "could potentially be measured in billions of existing medical brain scans." The researchers cautioned against making a causal link between brain structure and behavior because more research will be needed to establish whether or not structural changes in the brain will lead to changes in risk attitude or if an individual's risky behavior affects brain structure.

"The findings fit nicely with our previous findings on risk attitude and ageing. In our Proceedings of the National Academy of Sciences 2013 paper we found that as people age they become more risk averse," Tymula said. "From other work we know that cortex thins substantially as we age. It is possible that changes in risk attitude over lifespan are caused by thinning of the cortex."

The study participants included young adult men and women from the northeastern United States.  The study subjects were asked to make choices between monetary lotteries that varied in their degree of risk. The research team also took anatomical MRI brain scans and found their results in a group of 28 participants and another encompassing 33 individuals.

The study was a collaboration of researchers from the University of Sydney, Yale, University College London, New York University, and the University of Pennsylvania. In addition to Tymula, authors include Sharon Gilaie-Dotan, Ifat Levy, Nicole Cooper, Joseph W. Kable, and Paul W. Glimcher. The findings were published Sept. 10 in the Journal of Neuroscience.