Do you approach life with a zest for decision-making? Do you bushwack through ambiguities to create a clear path? Or do you seesaw between opposing opportunities — unable to bear the weight of either one in the final analysis.
David Orenstein-Brown writes about a study at Brown University, supported by the National Institute of Neurological Disease and Stroke and the National Institute of Mental Health, where researchers show that “explorers” — those who tend to grapple head on with uncertainty by choosing the unknown — have this predilection because of the way their brains are structured. Co-author David Badre, assistant professor of cognitive, linguistic, and psychological sciences, says that the study shows an aspect of the brain’s architecture for producing decisions and learning. Apparently the right rostrolateral prefrontal cortex is the place where uncertainty comparison is performed for supporting a decision-making strategy.
How did it go? Badre and his colleague Michael Frank slid 15 participants under a MRI scanner while giving them a game to play. They had to stop the sweeping hand of a virtual clock to win points in different rounds. They were told that if they acted quickly in some rounds and slowly in others they could maximize their rewards. The uncertainty came because they did not know round-to-round which response occurred, and the number of points they could win fluctuated widely. They had to come up with a strategy to figure out how to maximize their rewards among uncertain options while they kept track of the current expected value of fast and slow responses in each round. The MRI scanner tracked the blood flow in the brains (neural activity) while the clock tracked the timing of the responses. This data was fed into mathematical models which tried to find a correlation between the response time and the uncertainty of the decision. Such a correlation pattern emerged.
Badre and Frank reasoned that this correlation would show up in the brain scans and sure enough it did. When the relative uncertainty between choice options got bigger, so did activation in the right rostrolateral prefrontal cortex. This effect was substantially stronger in the explorers than the non-explorers. This study is the first to show that this region of the brain keeps track of the decision-making process while guiding exploration. It also shows a variation in a gene called COMT that affects dopamine levels in the prefrontal cortex.
Frank admits that we still don’t know why some people are “explorers” while others are not. He does say that nobody likes ambiguity. Some of us don’t like ambiguity when it comes to making a single decision while others don’t like it in regards to a strategy over the long run.
What is this study good for?, you might ask. “There are a lot of diseases and disorders that affect the frontal lobes,” Badre says. “They affect the ability to live independently, to carry out the day and make good decisions that get you where you want to go. The more we know about the specificity of these systems, the better that you can diagnose and suggest treatments.”