Monday, May 14, 2018 by David Williams
Personality may have very little to do with people’s proclivity for risk, a new study reveals. Based on the results of the new study, the way people tend to respond to risky odds and risky situations entirely depends on how their brain is wired, as well as how different they are in this regard to other people.
The work of a professor named Joseph Kable from the University of Pennsylvania served as the evidence for this somewhat surprising conclusion. He devised a simple thought experiment, and a game of sorts. He offered one simple choice: You can walk out of his lab with a full 20 dollars no questions asked, or try your luck at winning bigger prizes by rolling dice. The chances of winning the bigger prizes were at around 40 percent, and the highest prize at stake was almost 100 dollars.
After analyzing all of his test subjects, Kable came to a clear conclusion. But before diving right into the test results and the conclusion of the study done by Kable, it’s important to understand the background a bit more. (Related: Neuroscience journal confirms adverse effects of fluoride on brain development.)
It is said that the study involved a total of 108 people aged 18 to 35 years old. They were all given 120 scenarios in which they needed to decide between a guaranteed payoff of 20 dollars, mentioned earlier, and the chance to win much bigger cash prizes with different amounts of risk. If he were an economist, Kable would have probably said that any decisions made by the test subjects were down to how much risk their personality is willing to endure. But since he is a neuroscientist, he linked their decisions and subsequent actions with matters involving their brains.
According to Kable, the varying degrees of risk for the various payoff amounts were set deliberately. “So [it was] either the $20 for sure versus a 50 percent chance for a $40 or a 70 percent chance for $30 or a 10 percent chance for $90.” All of the study’s participants didn’t know which one of the scenarios would be used as the basis for how much they got paid, so they needed to play all 120 scenarios as if they were all real. Kable then put a score to each individual’s tolerance for risk after looking at how they decided in all the different scenarios.
In a separate portion of the study, the participants were asked to quietly sit through a number of different brain scan types, without being asked anything at all. Subsequent MRI scans then revealed the sizes of their individual amygdala, the region of the brain that’s in charge of processing fear and other emotions, as well as the baseline level of activity in the amygdala and the medial prefrontal cortex, an area of the brain that’s said to be in charge of decision-making. A third brain scan was also conducted with the use of a technique called diffusion tensor imaging, and it was intended for revealing anatomical connections made of nerve fibers and link the amygdala and medial prefrontal cortex together.
Kable and his team gleamed from the results that the people who take the biggest risks tended to be the ones with the larger amygdala, and fewer connections to the medial prefrontal cortex. However, despite having fewer links, the two regions appeared to be more coordinated in terms of activity. This was called functional connectivity, and was noted to be present in those who liked to take risks over those who liked to play things safe.
These results were found to be quite impressive, particularly by Ifat Levy, a neuroscientist at the Yale University School of Medicine who was not a part of the research team. He said that the study presents a fuller picture of the anatomy and function of the brain with regards to risk-taking in humans.
“I could really on ly speculate, especially because the results are quite complex,” she said. “Maybe it’s a pruning, or getting rid of, unnecessary connections – leaving just the ones that are needed – and then the functional connectivity actually gets stronger.”
Learn more about how the human mind works in Brain.news.