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What is happening in our sleep?
Today, everyone knows that sleep is a complex human activity, not all a simple rest. There we finally rest with ourselves and nobody else. Admired with curiosity and respect by ancient philosophers and scholars sleep and dreams have always been inaccessible to any contact, except for speculation. Not any more. The electroencephalogram entered into clinical use in the 50's. In the 70's were mounted the first laboratories of polysomnogram in USA. In the 90s they arrived in Brazil. Today, there are only 4 in Curitiba, where people sleep linked to several types of sensors, and the sleep is analyzed in detail. In 30 years a great amount of knowledge has been accumulated.
There are 5 different types of sleep, called stage 1, 2, 3, 4, and REM stage. Phase 1 is the stage that we enter when we sleep over a minute before the hour of departure of Formula 1, early on Sundays. At this stage we are easily fooled. The brain activity, reflected by electroencephalogram, is slower and less organized. Many of the people who complain of insomnia and say they spend the whole night waken are actually between phases 1 and 2 most of the time. The problem with these people is that the brain counts this time as sleep, and does not cause an increased need for sleep for the night ahead. Phase 2, during which it is still easy to be waken, is exuberant in the ctroencephalogram of adults and children, with beautiful and big waves, other minors, the spindles, all this activity coming out quite of the top of the head. Phases 3 and 4 are deep sleep. The electroencephalogram shows huge slow waves occupying the entire brain, and could fall outside the biggest thunderstorm that we won’t gather any knowledge about.
In phase R.E.M. the eyes move in quick jumps from one side to another, breathing becomes regular, the inert body due to a muscle paralysis, and we dream. It is the stage of Rapid Eye Movements. During a night of 8 hours of sleep, a person goes through the sequence of stages 2 or 3 times, going from 1 to 4, and again from 4 to 1, via the REM stage after passing through 4. So dreaming about 2 or 3 times each night, and almost waking up after dreaming each time. So a good night's sleep is composed of many items, called as rules of sleep hygiene (see in www.unineuro.com.br) that help people to achieve this goal.
Without doubt dreams are one of the most striking phenomena that occur in humans. They are in some ways reminiscent of certain crisis of some forms of epilepsy, or migraine, or attacks of panic. Viewed another way to seem part of a world with other rules, chaotic, definitely far from our control. One hundred years ago, at the turn of the nineteenth century to the twentieth century, Freud formulated the hypothesis that the dreams would be images of our unconscious, representing our fears, desires and traumas. The crucial assumption of Freud, and one of the main pillars of psychoanalysis, is that dreams have a very important psychological significance, related to the structure of personality. During these 100 years hundreds of thousands of sessions of psychoanalysis were used to interpret dreams according to the hypothesis of Freud. Many who know the work of the old Freud, including this author, feel that his masterpiece is "The interpretation of dreams." However, psychoanalysis has not proved his theories in science.
It is in the laboratories of polysomnography that neurologists who have just stated the dreams are nothing more than a mental noise, such as a little noise from a computer processor. The brain reviews what happened during the day, compares with what has terminated, most files, and so on, a service that is continuous throughout the life of the person. Dreams are a product of chance comparisons of these images. However, results of more recent researches return to a field similar to that proposed by Freud: perhaps the dreams have a function as part of an emotional thermostat, in some way linked to the emotional intensity of our experience. The mere existence of dreams indicates that the view has some importance in the organization of our emotions. Many dreams have great emotional content, while an entirely visual experience. If you woke soon after a dream of strong emotional content, you’re at the risk of remaining in the state, happy or sad, throughout the day.
Studies of neuroimaging called PET and SPECT indicate that during the REM stage the limbic system works well, while the pre-frontal cortex, which handles the reason and intellect, is stopped. The limbic system is an older part of the human brain, which exists in dogs and cats. In humans these areas are directly linked to emotions more out of our control, those which we recorded as part of our personality that are profound. The results of these studies seem to indicate that dreams are a noise resulting from the processing of the images of the day, or perhaps the week or the month, which includes a comparison with previous experiences, and eventual closure. This line of reasoning suggests that dreams can have a strong connection with the memory, at least with the emotional memory.
Unfortunately good dreams are rare, so that there is not a word that is the opposite of nightmare, at least in the languages that the author knows. Anyone who has had good dreams, awoke with them, tried to sleep again and continued, know that with a bit of calm you can finish, take the ultimate consequences, that courtship that only occurs in REM stage. The nightmares seem to be a way to deal with the emotional content of what is happening during the vigil. Not exactly that day, because dreams are often completely displaced in time. It seems that when we are conscious of the things we are playing with our concepts of consciousness. We do not have time or conditions for considering the emotional reverberations of what will occur.
And the recurring nightmares? There are some who are even common to many people, to feel like that falling in a vacuum, until the guy wakes up soaked in sweat. Or the other person's running to catch a plane, and has passed the time of shipment and is still stuck in traffic and wakes up all wet. As a general rule, nightmares overpaid, or even dreams of any kind in excess, indicate that the person is more reminiscent of dreams than he should. To remember the dreams a person needs to wake up. So dreams in excess mean a pattern of sleep very superficial. The environment and hygiene of sleep may not be well settled. Or the person may be suffering from anxiety. Indeed the common types of nightmares once described above is very suggestive that the customer is at least in a period of anxiety. At best, he is in need of treatment.
So will the science of the twenty-first century prove the old theories of Freud? Yes, in the sense that the dream has to do with our unconscious and with our emotions. But they are not as important with such structural portions of our personalities. After all, many people remember going 10 years without any dreams. A review of the process of archiving of the visual memory and emotional is the most likely function of dreams.
Prof. Dr. Paulo RM de Bittencourt, PhD
