What is a dream? The dictionary defines this word as 'a series of thoughts, images, and feelings that you experience when you are asleep'. In other words dreams are imaginary sleeping visions. People spend one third of their lives asleep but they don't fully understand the purpose of dreams. Freud believed that dreams are people's unconscious wishes that they are not allowed to express in real life. Some scientists think that dreams allow us to solve problems, to create new ideas and to find answers to the most complicated questions. There are some corroborations of this theory. For example a famous Russian scientist Dmitri Mendeleyev invented the periodic table after he had seen it in his dream. The modern theory is that dreams are the brain's way of organizing the events of the day and deleting the information that it doesn't need. It is like the cleaning-up operations of computers.
Some of our dreams are very strange and don't make sense at all. When we sleep, some areas of our brain are active while others are not. Scientists have proved that the frontal lobes that control emotion, memory, and experiences are active, but the areas that control rational, logical thought are not active at all. Our dreams depend on our emotional state as well. When we are depressed, we usually have dreams which make our sleep disturbed. When we fear something, we may have a nightmare. We can experience intense feelings while sleeping: a sense of exhilaration, joy and excitement or anxiety, trepidation and alarm. The more we think about a person, the more likely we are to dream about him. If we are preoccupied with some problems, we will continue thinking about them while sleeping. That's why the Chinese say, 'What you think during the daytime you will dream at night'.
People's dreams have various scripts but there are some common themes. For example most people dream about flying, being chased, falling or not being able to move. People have always sought meaning in dreams and considered them to be predictions of the future. There are a lot of books trying to interpret our dreams and to explain what the future holds. So if we dream about being chased, we are running away from something in real life. A dream about crossroads symbolizes that soon we will have to make an important decision about business or love. Finding money may symbolize a birth. Crossing a river means a fundamental change of lifestyle. Dreaming about a rainbow predicts good news.
Doctors assert that if a person wants to be healthy and to live long, he must sleep 8 hours per night. But some people (for example night-shift workers) are deprived of normal sleep. Some of us suffer from insomnia because of the distortion of the natural rhythm of sleep occasioned by noise, anxiety, excessive tiredness or excitement and many other factors. But a person needs his amount of sleep and he can do without it only temporarily. If he has missed a lot of sleep, he looks tired, becomes absent-minded and makes many mistakes. So sleep is important both to our body and mind.