Scientists are still unsure about why we dream and why we dream about certain things rather than others. A series of studies by researchers at Carnegie Mellon University looked into the significance people give to dreams and found that most people believed they contain important, hidden truths. One study of 149 students in the U.S., India and South Korea asked them to rate different theories about dreams. In all three countries an overwhelming majority of the students believed that dreams revealed hidden truths about themselves or the world. In another study 182 commuters at a Boston train station were given four different scenarios about things that had happened the night before a plane trip: that the nation's security threat had been raised to orange, that they had consciously thought about their plane crashing, that a real plane crash had occured on the route they were about to take or that they had dreamt about a plane crash. Dreaming about a plane crash was more likely to make people change their travel plans. A third study asked 270 people in the U.S. to remember a dream they had had about someone they knew. People gave more importance to pleasant dreams about people they liked than about people they didn't and gave more importance to unpleasant dreams about people they disliked. Finally, when people were asked about their religious dreams religious people were inclined to take seriously any dream involving God, whereas agnostic people only took the dream seriously if God had asked them to do something pleasant.
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