Vol. 311. no. 5763, p. 935
DOI: 10.1126/science.311.5763.935
News of the Week
PSYCHOLOGY:
Tough Decision? Don't Sweat It
Greg MillerBuying oven mitts and buying a car demand completely different types of decision-making. Most people would scarcely think about the mitts and agonize over the car. That's exactly the wrong way to go about it, according to a provocative new study.
On page 1005, Ap Dijksterhuis and colleagues at the University of Amsterdam in the Netherlands report a series of experiments with student volunteers and real-life shoppers that suggests that too much contemplation gets in the way of good decision-making--especially when the choice is complicated. Conscious deliberation is best suited for simple decisions such as choosing oven mitts, the researchers argue, whereas complex decisions like picking a car are best handled by the unconscious mind.
"They're elegant experiments with a simple design and eye-popping result," says Timothy Wilson, a psychologist at the University of Virginia in Charlottesville. The research should "stimulate some useful new thinking" among decision researchers, says Daniel Kahneman of Princeton University.
The problem with conscious thought, Dijksterhuis contends, is that you can only think about so many things at the same time. He hypothesized that decisions that require evaluating many factors may be better handled by unconscious thought processes.
To test the idea, Dijksterhuis and colleagues asked volunteers to read brief descriptions of four hypothetical cars and pick the one they'd like to buy after mulling it over for 4 minutes. The researchers made the decision far simpler than it is in real life by limiting the descriptions to just four attributes such as good gas mileage or poor legroom. One of the cars had more plusses than the others, and most participants chose this car. But when the researchers made the decision more complex by listing 12 attributes for each car, people identified the best car only about 25% of the time--no better than chance. The real surprise came when the researchers distracted the participants with anagram puzzles for 4 minutes before asking for their choices. More than half picked the best car. The counterintuitive conclusion, Dijksterhuis says, is that complex decisions are best made without conscious attention to the problem at hand.
To test the idea in a more natural setting, the researchers visited two stores: the international furniture store IKEA and a department store called Bijenkorf. A pilot study with volunteer subjects had suggested that shoppers weigh more attributes when buying furniture than when buying kitchen accessories and other simple products commonly purchased at Bijenkorf. The researchers quizzed shoppers at the two stores about how much time they'd spent thinking about their purchases and then called them a few weeks later to gauge their satisfaction. Bijenkorf shoppers who spent more time consciously deliberating their choices were more pleased with their purchases--evidence that conscious thought is good for simple decisions, Dijksterhuis says. But at IKEA, the reverse was true: Those who reported spending less time deliberating turned out to be the happiest.
Jonathan Schooler, a psychologist at the University of British Columbia in Vancouver, says the study builds on evidence that too much reflection is detrimental in some situations. But "it adds an important insight" by identifying complexity as a key factor in determining which kind of thought process leads to the best decision. Schooler isn't ready, however, to dispense with conscious thought when it comes to complex decisions. "What I think may be really critical is to engage in [conscious] reflection but not make a decision right away," says Schooler.
Dijksterhuis agrees. When an important decision arises, he gathers the relevant facts and gives it his full attention at first. Then, he says, "I sit on things and rely on my gut."
