Making a Decision? Don't Sleep on It

Study Shows 'Thinking Things Through' Beats Unconscious Thought for Big Decisions

(WebMD)  Struggling with a big decision can keep you up at night. That might not be so bad.

Sleeping on it could lead to a poor choice, according to new research published in the Quarterly Journal of Experimental Psychology.

Complex decisions, such as buying a house or car, require careful, conscious deliberation, the new study suggests. The results are a stark contrast to a 2006 Science report that found that snap judgments and unconscious thought -- like sleeping on a problem - were best for solving major dilemmas. Headlines touting such gut-instinct decision-making actions can be "misleading," even "outright dangerous," says University of New South Wales psychologist Ben Newell, author of the new study, in a news release.

"We found very little evidence of the superiority of unconscious thought for complex decisions," Newell says. "On the contrary, our research suggests that unconscious thought is more susceptible to irrelevant factors, such as how recently information has been seen rather than how important it is."

Unconscious thought is promoted as an active process during which the brain organizes, weighs, and integrates information in an optimal fashion. Proponents argue that unconscious thought is best for making a complex decision - one that requires narrowing down lots of options and attributes - because it's not limited by conscious interruptions. However, opponents say conscious thinkers can make choices that are at least as good if they have enough time to sort through all information or can consult material while thinking it through.

The new findings are based on the results of four experiments in which college students were asked to choose the best option when faced with complex decisions, such as choosing to rent an apartment or buying a car. The students were asked to make a decision in three ways: immediately ("blink"); after conscious deliberation ("think"); or after a period of distraction ("sleeping on it.")

All experiments showed that thinking it through, or conscious thought, lead to better choices. There was little proof that sleeping on it led to better decisions.