Money on the Brain
There’s a logical reason why we sometimes make irrational decisions—it’s how we are wired.
Consider this moral dilemma. Warfare has disrupted food shipments to a children’s home in southern Uganda. Sixty orphans live there, and you must decide how to reallocate their meager rations. You have been given two choices: Either you can take six meals away from each of two children or 10 meals away from one. The first choice is less efficient because it results in fewer overall meals for the children (12 meals lost versus 10), but the latter choice is more equitable. What do you do?
While you deliberate, an MRI machine is recording your brain activity. The orphanage is real—Canaan Children’s Home in Buziika, Uganda—and so are the consequences of your choice: the amount of donation the orphanage receives will be affected by your decision. To make your decision all the more agonizing, the children gaze at you from a computer screen as you maneuver a lever between the two options.
“People became very emotional, telling me it was the hardest experiment they had ever done,” says University of Illinois economist Ming Hsu of the 26 people, ages 28 to 55, who subjected themselves to just such a moral quandary as part of an effort to map how economic decisions occur in the brain. He points to MRI scans in which two regions of the brain glow intermittently like warning lights. The putamen, a reward center, was lit whenever one of the subjects thought about efficiency in making their choice, but the insula cortex, where emotion is centered, blared yellow whenever a participant contemplated taking food away.
Even though activity varied considerably among the subjects, the insula dominated, “and people overwhelmingly chose equity,” says Hsu. “And what this tells us is that contrary to what standard economic theory predicts, people value fairness. It is a basic human response.”
By Holly Korab