Sleeping on a problem may really be the best way to solve it, researchers have discovered. Distracting yourself for a few minutes with something else or, even better putting off the issue until the next day, helps the brain come up with the ideal solution, the study found. According to experiments, people who consciously struggle with a difficult question are more likely to get the wrong answer, compared to those who put it on the mental backburner. In the tests, students were asked to choose the best models from four imaginary makes of car. Each one had 12 different features but two had better road holding and fuel economy. After reading about each car, one group of students was asked to make an instant choice. Another group carried out a second test which was designed to occupy their minds for five minutes before making their decision. Volunteers in that group, dubbed the "unconscious thinkers", were more likely to select the best car, the results showed. Dutc...