Woman contemplating what to get at a vending machine

People make different decisions at vending machines if they speak their selection versus pushing a button. (Photo Credit: Shutterstock)

How decision expression alters decisions

The way we express an opinion – verbally, manually or on different devices - can change the very nature of the decision.

Confronted with a well-stocked vending machine, your brain may say "Twix," but your hand is more likely to push a button associated with the healthier fruit snack. Your hand reveals your good intentions, but if asked to state your preference, your mouth is more likely to name your impulse – the candy bar.

That's according to work by Jonathan Levav, an associate professor of marketing at the Graduate School of Business, in conjunction with his colleagues Anne-Kathrin Klesse from Tilburg University and Caroline Goukens at Maastricht University, both in the Netherlands.

The team realized that people express their preferences in many ways, from ordering food at a restaurant or pushing buttons on vending machines to placing orders on a computer or other device. They were curious whether the actual way a person expressed a decision altered the decision itself.

The group carried out several experiments, each allowing people to make a food selection either verbally or manually. In each case, the people who made the choice verbally chose the more indulgent option, whether it was candy at a vending machine or a sweeter dessert.

"There is a relationship between the amount of work and the choice," Levav said. "You know the banana is a better option but you have to think about that."

When people have to concentrate by speaking in a foreign language or by writing, they make choices similar to when they push buttons. Both require activating a part of the brain involved in thinking, which is also required for exerting self-control.

Speech, by contrast, bypasses that brain region.

Since conducting that initial set of experiments, Levav and his collaborators have carried out another study to find out how satisfied people are with their decisions. They had people choose to taste one of two colas, either verbally or by pressing a button.

"In the out-loud condition, people are always more satisfied with their choice," Levav said, even though the two colas were identical. "People who spoke their selection were more likely to think they drank a national brand soda rather than a store brand."

If people wear noise-canceling headphones while speaking their selection, the effect goes away. Levav said that's probably because it takes concentration to speak without being able to hear, making the speech more like pushing a button.

If speaking a choice and choosing candy by pushing buttons seem similar but yield surprisingly different results, get this: It turns out people make more hedonistic decisions in configuring a car, bike or spa package when on an iPad than on a computer.

Taken together, the work suggests that the way we go about expressing our decisions alters the very decisions themselves.

What to read next:

teenager and grandfather


The brain changes at different stages of life, and way we weigh decisions changes with it

business people brainstorming

Group Dynamics

Groups of people make better or worse decisions depending on the composition of the group and experience of the leader

alcohol and driving


Our brains evolved to value near-term rewards over long-term threats, and that wiring creates challenges for treating addiction