Dreams affect people's judgment, behavior

While science tries to understand the stuff dreams are made of, humans, from cultures all over the world, continue to believe that dreams contain important hidden truths, according to newly published research.

In six different studies, researchers surveyed nearly 1,100 people about their dreams. "Psychologists' interpretations of the meaning of dreams vary widely," said Carey Morewedge, an assistant professor at Carnegie Mellon University and the study's lead author. "But our research shows that people believe their dreams provide meaningful insight into themselves and their world."

The article appears in the February issue of the Journal of Personality and Social Psychology , published by the American Psychological Association.

In one study that surveyed general beliefs about dreams, Morewedge and co-author Michael Norton, an assistant professor at Harvard Business School, surveyed 149 university students in the United States, India and South Korea. The researchers asked the students to rate different theories about dreams. Across all three cultures, an overwhelming majority of the students endorsed the theory that dreams reveal hidden truths about themselves and the world, a belief also endorsed by a nationally representative sample of Americans.

In another study reported in the article, the researchers wanted to explore how dreams might influence people's waking behavior. They surveyed 182 commuters at a Boston train station, asking them to imagine that one of four possible scenarios had happened the night before a scheduled airline trip: The national threat level was raised to orange, indicating a high risk of terrorist attack; they consciously thought about their plane crashing; they dreamed about a plane crash; or a real plane crash occurred on the route they planned to take. A dream of a plane crash was more likely to affect travel plans than either thinking about a crash or a government warning, and the dream of a plane crash produced a similar level of anxiety as did an actual crash.

Finally, the researchers wanted to find out whether people perceive all dreams as equally meaningful, or whether their interpretations were influenced by their waking beliefs and desires. In another study, 270 men and women from across the United States took a short online survey in which they were asked to remember a dream they had had about a person they knew. People ascribed more importance to pleasant dreams about a person they liked as compared to a person they did not like, while they were more likely to consider an unpleasant dream more meaningful if it was about a person they disliked.

"In other words," said Morewedge, "people attribute meaning to dreams when it corresponds with their pre-existing beliefs and desires. This was also the case in another experiment which demonstrated that people who believe in God were likely to consider any dream in which God spoke to them to be meaningful; agnostics, however, considered dreams in which God spoke to be more meaningful when God commanded them to take a pleasant vacation than when God commanded them to engage in self-sacrifice."

The authors say more research is needed to explore fully how people interpret their dreams, and in what cases dreams may actually reveal hidden information.. "Most people understand that dreams are unlikely to predict the future but that doesn't prevent them from finding meaning in their dreams, whether their contents are mundane or bizarre," said Morewedge.