As far as we know, all animals dream; and humans probably started to dream even before they were sufficiently intelligent to think about the process. It has been suggested that some of the earliest prehistoric cave paintings are records of dreams. Freud set out the theory that, although they may be
prompted by external stimuli, wish-fulfillment was the basis of most dreams. According to him, our dreams reflected our deepest desires, rooted in our infancy, and always held a serious meaning. He stressed the erotic content of dreams. Carl Gustav Jung collaborated with Freud for some years, but disagreed with him on this very point: hidden sexual problems were not, Jung argued at the root of most dreams. Freud believed that dreams were the result of concealed desires and, continued, on the whole, to conceal them; Jung, on the other hand, felt that dreams revealed our deepest wishes and longings enabling us to realize our unconscious ambitions and helping us to fulfil them. Jung suggested that dreams are, in fact, important messages from ourselves to ourselves, and messages that we ignore to our loss. Most modern psychologists tend to lean towards Jung rather than Freud. Freud would have denied that someone could be taught to interpret their own dreams; whereas Jung believed that although it was a difficult task it could and should be done for, dreams were “meant” to be understood. The idea of losing consciousness, of ceasing to be ourselves, and of relinquishing all control over our thoughts and movements, is dreadful to us; and yet it happens every night when we sleep, For centuries, people thought of sleep as a period when humans rested their bodies and their minds. Even in the early part of the last century, It was believed that during the day, blood rose to the brain and caused congestion there. During sleep, the blood drained back into the rest of the body (and therefore it was best to sleep without a pillow so that the blood could flow more easily from the brain). Early this century, scientists suggested that certain chemicals, such as lactic acid, carbon dioxide and cholesterol, collected in the brain during waking hours and were then depleted during sleep. The question remains, what is the purpose of sleep? No cases have ever been recorded in which physical illness has resulted from lack of sleep, although the brain probably does need sleep, since measurements of brain activity have shown some chemical changes during sleep deprivation.
The modern understating of the nature of sleep began just over 40 years ago. In 1952, a researcher noticed that at certain times during a period of sleep the eyes of the subjects could be seen stirring beneath their closed lids – as though they were watching moving figures. These motions were called “rapid eye movements” and the phases of sleep were called REM periods. Three years later, it was found that during REM sleep, the flow of blood to the brain increased, as did the brain’s temperature, particular brain wave patterns showed up on an electroencephalograph (EEG). Irregularities in breathing and heartbeat were noted during REM sleep, and a reduction in electrical activity in certain muscles. It was also discovered that if a person was woken up during REM sleep, they could usually remember vivid dreams; while only about six per cent of people woken during NREM (non-rapid eye movement) sleep claimed to have been dreaming. It seemed to be the case that only during NREM sleep were humans really “unconscious”, and apparently indulging in complete rest. Although about half of the people awakened during this period believed they had been dreaming, they thought that their dreams were more like daydreams – seeming less surreal than “real” dreams. These discoveries were so interesting that they led to an intense period of the study of sleep patterns, and most of our knowledge about the nature of sleep emerged from studies made over the next 20 years.
When we fall asleep we enter a cycle of sleep – a pattern that is usually repeated several times during the night. Scientists identify four stages of sleep – the first stage is simply a transition from wakefulness to real sleep; while stage two may be described as “normal” sleep. During stage three, there is another transition, or sinking into a deeper sleep – that of stage four. During sleep, what is happening in the brain can be measured by the use an EEG. Electodes placed on the scalp pick up “brain waves” of about one – millionth of a volt in strength, which are amplified and traced on paper or recorded on tape, where changes in frequency (the number of waves taking place within one second) can be seen. Four types of EEG have been particularly studied: Beta waves are fast waves that show when the brain is animated or anxious. Alpha waves which show during periods of meditation, when the brain is wakeful but relaxed. Theta waves occurring during drowsiness or light sleep; and Delta waves slow waves that are seen during times of deep sleep. The whole cycle lasts around ten minutes of REM sleep, when dreams occur, before “climbing” back through three layers of NREM sleep. The whole cycle lasts around 80 or 90 minutes. During perhaps four cyles repeated throughout a single night’s sleep, we spend around six hours in NREM sleep, and the remaining two in REM “dream-time”. Just under half of us wake only from NREM sleep, and these include those people “who claim that they never dream.” It has been suggested by some psychologists that these people unconsciously wake themselves at a time when they are not dreaming because they want to repress what their dreams are telling them.
1. If you get up actually remembering a dream, then you would most probably have got up from