Recently I decided to buy a new home and a new printer for my computer. Guess which decision took the most effort? If you guessed the printer, you guessed right. Turns out that that my choice of a house was perfect, and my new printer was a good choice too. Did I get lucky, or is there something else happening?

Contrary to conventional wisdom, it is not always advantageous to engage in thorough conscious deliberation before choosing. Several different experiments looked at what researchers called the “deliberation without-attention” effect. It’s a take on when to “follow your gut” and when to make a well-thought-out decision.

For relatively simple decisions (like buying a printer) it is better to use a highly rational and researched approach. However, when making a complicated decision (like buying a house) the unconscious appears to do a better job of resolving factors and making a sound conclusion. Of course this goes counter to the conventional approach most of us use to make everyday decisions.

To test the “deliberation-without-attention” hypothesis, four studies were done on how consumers made choices. Some of the experiments were done in a laboratory setting and others used real shoppers.

One experiment involved the purchase of a new car. The participants were given reading material including positive and negative information about four hypothetical automobiles. Other participants were asked to just think about the cars for four minutes and choose one. Still other participants were distracted for four minutes with another task and then asked to choose a car. While those who had time to think about their choice made good decisions when the information was simple (only four attributes listed per vehicle), they more often made poorer choices when the information became more complex (12 attributes listed per vehicle).

In another study, shoppers were quizzed about their purchases upon leaving an IKEA store and a department store. They were asked specific questions about the cost of their items, how much they had known about them before coming to the store, and how much time they thought about their purchases before they bought them. Follow-up telephone interviews revealed that shoppers who spent more time deliberating about simple purchases (such as kitchen accessories) and less time deliberating about more complex purchases (such as furniture) were ultimately more satisfied with their choices.

The idea that the unconscious plays an important role in the cognitive process comes right out of Freudian psychology. Conscious thought does not always lead to making a good decision because it has low capacity. We can only think about a few options at any time; a person can pay attention to only a limited amount of information at once. This can cause people to focus on small things (like a car’s cup holders) and not see the bigger picture. “Option paralysis” can result when there are too many factors and we keep coming to different conclusions. The unconscious mind is capable of processing a larger amount of information, but with less precision.

Then there is the “weighing problem.” A conscious mind can give too much weight to some factors and not enough for others. People can overestimate the importance of a house’s square footage and underestimate the commute to work.

New York Times science reporter Malcolm Gladwell popularized this research in his bestselling book Blink. Gladwell wrote about the power of the unconscious mind and it’s ability to “thin slice.” Thin slicing refers to the mind’s ability to find patterns in certain situations based on very narrow information from past experiences. In one reported experiment in Blink, experimenters asked people to decide if a couple was likely to divorce after seeing them for a few seconds. This snap judgment was often more accurate than if people were given more detailed information about the couple.

Not everybody agrees with the “deliberation-without-attention” hypothesis. Some critics call the hypothesis mere pop psychology and part of a larger trend of a return to Freudian concepts. And what about life or death decisions like being on a jury or making costly investment decisions? Like most good research, it raises more questions than it answers.