Deliberate Decisions Are the Best

When it comes to making life-changing decisions, neither snap judgments nor "sleeping on it" trump good old-fashioned conscious thought, new research suggests.

The finding contradicts research reported in 2006, which suggested unconscious thought is optimal for making complex decisions, including whether to buy a certain house or car. The 2006 findings, made by Dutch researchers and published in the journal Science, supported ideas of making quick decisions or leaving complex choices to the powers of unconscious thought.

"Claims that we can make superior 'snap' decisions by trusting intuition or through the 'power' of unconscious thought have received a great deal of attention in the media," said Ben Newell, a psychologist at the University of New South Wales and lead researcher of the new study that was announced today.

Newell and colleagues presented participants with complex decisions and asked them to choose the best option immediately, after a period of conscious deliberation or after a period of distraction (the "sleep on it" method), which is thought to encourage unconscious thought processes.

In all experiments, there was some evidence that conscious deliberation can lead to better choices and little evidence for superiority of choices made "unconsciously," the researchers said. 

Faced with making decisions such as choosing a rental apartment or buying a car, most participants made choices predicted by their individual preferences for certain features (for example, safety, security, color or price), regardless of the mode of thinking employed.

Unconscious decision-making was thought to be best in certain situations because it is not limited by how much stuff can be shuffled through the mind — a limitation thought to hobble conscious thought. And so, scientists had said the benefits of unconscious thinking are greatest when a decision is complex, with multiple options and attributes.

"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," Newell said. "If conscious thinkers are given adequate time to encode material, or are allowed to consult material while they deliberate, their choices are at least as good as those made 'unconsciously.'"

The results will be published in The Quarterly Journal of Experimental Psychology.

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