Picking the Perfect Present

During this shopping season, have you found yourself standing frozen with a potential present in your hand, wondering if your mom would like it? It may feel like a tiny wrestling match, but what is actually going on in your brain?

Baird Term Assistant Professor of Psychology Joseph Kable is starting to answer that question. A neuroeconomist, Kable uses economic theory as a basis to study brain processes—in this case, the assumption that people are trying to be as rational as they can be. “This theory doesn’t explain all of behavior, and the fringes where it seems to break down are interesting. But rather than starting with the exceptions, let’s start at the core.”

This would mean that the first step in making a decision is for the brain to consider all the pros and cons of each option and collapse that into a summary verdict. Kable recently conducted a meta-analysis of the decade’s worth of decision-making studies that have been done using non-invasive functional brain imaging. He showed that there is a consistent signal of neural activity that corresponds with the subjective valuations people put on the choices—that they are indeed assigning values to the options.

Sometimes that assessment is easy: Would you rather have $1 or $2? Most decisions are more complicated and involve tradeoffs. One example is the classic “marshmallow test”—whether a four-year-old would rather have one marshmallow right now, or two at some later time. Researchers had found that kids will often wait for a time, but then give up and eat the single marshmallow. It’s important because research also shows that people’s ability to wait for a reward is linked to many traits that contribute to success in life, such as academic achievement, health and addiction, even divorce rates. 

Kable and postdoc Joseph McGuire recently discovered that the test results change if the waiting period is specified. “Our intuition is that when we are waiting for something, the longer we wait, the closer and closer we get to that thing,” Kable says. “But what we found is that if you don’t know anything about when the outcome will occur, the longer you wait, the more you think you’re getting farther and farther away from that outcome.” On a recent trip to New York City, he discovered that the subway system had figured this out—they now have clocks that tell the time to the next train. “Waiting isn’t so much of a problem when you have certainty about when the train’s coming.”

Can this be used to help people learn to delay gratification? “There are two questions,” says Kable. “Can we get people to choose delayed rewards over immediate, and can we promote persistence, so that you keep working toward your goal?”

Kable is working with Caryn Lerman, Mary W. Calkins Professor of Psychiatry in the Perelman School of Medicine and the Annenberg School for Communication, to see if brain training to improve short-term memory leads people to be more patient. The study is based on data that show that the brain networks involved in short-term memory are more active in individuals who are more patient. He and his lab are also researching whether practice in visualizing future goals helps people be more patient, akin to sports therapists who have athletes visualize hitting the ball onto the green or serving an ace.

“If we want to encourage persistence, for people to really stick with it, we have to address the uncertainty,” he says. “To the extent that it’s possible to make the rewards fairly regular and predictable, that will help.”