Let’s say you’re at your desk, analyzing a major decision. You get partway, and then you take a break: You go to a meeting, or start daydreaming, or “sleep on it.” Your mind continues to work on the problem subconsciously. When you return to it consciously, your thinking will have advanced. The information will have been consolidated and restructured, even though you don’t notice it.
S+B: Do you mean that before making a decision, it’s a good idea to take time off and allow the unconscious to weigh in?
NORDGREN: In most cases, yes, but it depends on the nature of the choice. This is the more provocative claim of unconscious thought theory. In many cases, decisions made in a way that combines conscious and unconscious thought are superior to those made deliberatively.
Consciousness is like a flashlight in a dark room. It can sharply focus attention onto a particular issue or a narrow subset of information. But it has very constrained capacity. Try counting backward by threes while simultaneously putting together your grocery list for the week. You can’t do it; the processing capacity of conscious thought is so small that it is rapidly overwhelmed.
Unconscious thought, on the other hand, has a much higher processing capacity. This makes it particularly good at broad comparisons of large amounts of information, where some has more natural weight than others. If you’re choosing between two consumer products that are more or less the same—two oven mitts, say, with different colors—conscious attention alone will be adequate. For a more complex decision, you want to give your unconscious an opportunity to get involved.
Ap and I have tested this idea in many situations, both in the field and in the lab. In one experiment, for instance, we gave people information about four apartments in the Jordaan neighborhood in Amsterdam, and asked them to pick one apartment to recommend. Each apartment has positive and negative attributes—qualities like size, being next to the train tracks (and thus noisy), or having a desirable view of the canals. Choosing the apartment is a complex activity, and the quality of the choice can be tracked: By any objective measure, one of the apartments has more positive attributes than the others.
We’ve conducted this experiment in many different ways. We ask people to choose for themselves or for someone else. We give some people a lot of information and time to study it. We give others only a short amount of time, not enough to study the information. We ask some subjects to decide while counting backward by threes into a microphone, so they’re distracted.
The results have been fairly consistent. In general, people who spend time thinking over the options and studying them tend to do better than people who take no time, and who rely on an immediate gut feel. But a third group does better still. The best deciders study the information but then have their attention distracted. For example, if we give people information about the apartments, and ask them to take their time and think about it, and then, after a delay, we distract them, we see increased performance.
We’ve had similar results in other domains—for example, in betting on World Cup matches, expert predictions, making a car purchase, hiring people, or asking people to come up with innovative ideas. If the amount of expertise is basically the same, then those who engage in an incubation process—conscious, rational study followed by distraction and delay, during which unconscious processing kicks in—outperform those who just analyze. The unconscious is simply better at aggregating all the pros and cons associated with a decision, and dealing with that complexity.