Why do we "waste" one third of our life, sleeping? Why do we scare ourselves silly, dreaming? These are among the myriad of question that beg the answer "Why?"
With our present state of knowledge most of the "How" questions in life are fairly easy to answer. The answers to the "why" questions of human behavior are harder to find. They will only, and always, be found in the evolutionary development of human beings. -- Where else could these human attributes be derived from? Supernatural Beings? Visitors from outer space? Hardly. The real answers to the "why" questions rest in the realm of Evolutionary Psychology: The fairly new scientific arena that traces all human behavior to its evolutionary origins.
We will first examine the question: Why are human beings wasting one third of their life in a state of unconsciousness: Why do we have to sleep? After we have discovered why we need to sleep, we will try to determine why we dream when we are asleep.
Excerpt from Book: "How Life Really Works"
Book I: Man and the Universe
Chapter 06.00: Psychology: Human Emotions and Traits
Chapter 06.21: Sleep and Dreams
Due to space limitations, sections in Red are accessible only in the Book or CD "How Life Really Works".
Sleep and Dreams
Chapter 06.21 SLEEP AND DREAMS
The Interpretation of Dreams
Since time immemorial, the subject of sleep and dreams has intrigued man. Sleep fascinates people because it may be somewhat reminiscent of death: We lie down, we close our eyes and we are dead to the world. Apparently, only a few minutes later, without being aware of any loss of time, we get up again. Sleep is an event that conveys the subjective appearance of not happening at all. We are not aware of having slept. Sleep is a non-activity that seems to steal one-third of our life. Dreams, that are usually part of sleep, can be very unsettling and can even make us question our sanity.
In the past, a shroud of mystery has covered the subject of sleep and dreams. Little objective knowledge about the nature of sleep and dreams was available. What information about sleep was accessible, represented a murky mixture of facts and mystified conclusions, mired in superstition. Sleep, this condition of semi-consciousness, causes anxiety because sleep reduces our environmental perceptions and degrades our ability to respond to danger. We are concerned because we realize that we are very vulnerable while we are asleep.
Sleep involves the cessation of most of our sensory input and a reduction in most of our physiological processes: We are not aware of ordinary sounds; we close our eyes in order to eliminate visual input. On the physiological level, our limbic nervous system slows down our breathing rate and our heartbeat; it even reduces our blood pressure. Our autonomic nervous system curtails the production of waste products in order to prevent disruptions to our sleep. While our physiological functions operate at a minimal level, our brain also adjusts itself to reduced sensory input and operates on a very primitive level.
When we try to probe the mysteries of sleep, we are only moderately concerned with the changes in our physiological functions while we are asleep. After all, these functions are readily discernible and are fully under the automatic control of the autonomic nervous system. What really intrigues us, are the mechanics of sleep as it affects our brain and, therefore, our mind. What are the functions of our brain while we are asleep?
Before we can examine this question, we must understand the functions of our mind when we are asleep.
Sleep is a critical survival need, similar to eating, drinking and breathing. Sleep is not unique to humans. All vertebrates, animals with a segmented spinal column, do sleep to some degree. Fish and even reptilians or amphibians lower their sensory awareness for prolonged periods, similar to sleep in vertebrates.
We know little about the need for sleep of even more primitive living organisms such as bacteria or viruses. One can only surmise that there is no need for sleep in such primitive organisms. These little beasties seem to be busy around the clock, because they are not aware of diurnal rhythms. The need for sleep increases with the complexity of the organism and its nervous system.
Human sleep ranges from sleepiness to Stage 4 sleep, which represents profound insensitivity to external stimuli. When we try to fall asleep, we prefer to do so in an environment free of sudden noises and other external stimuli. After we have fallen asleep, our skeletal muscles relax and our nervous system severely curtails the entire range of our sensory perception.
Although electroencephalographs can readily measure the depth of our sleep objectively, we may also subjectively refer to being in a deep sleep, or sleeping fitfully. We are not concerned about the act of falling asleep because we know from experience that sleep is a regular occurrence and thus predictable. Sleep is unlike a coma, due to the ready reversibility of the condition and we are fully confident of a rapid return to a state of wakefulness.
In addition to the classification of sleep from Stage 1 through Stage 4, human sleep falls in other patterns. One of the major patterns refers to Non-REM sleep and REM sleep. REM stands for Rapid Eye Movement, the visually observable movement of the eyeball under the eyelid.
Periods of REM usually coincide with our dreams, whereas Non-REM sleep is essentially free from dreams. While we are dreaming, the brain deactivates our major muscle systems in order to preclude uncontrolled thrashing and potential injury. We may dream that we are running at top speed to escape from a monster, but our legs will merely twitch.
Stage 4, the stage of deepest sleep, usually occurs within the first hour of sleep. This is nature's way of assuring that we optimize badly needed sleep in case external events prematurely interrupt our sleep. At Stage 4, we are almost in a state of stupor and rather insensitive to moderate stimuli. It may be necessary to shake a person in this stage to awaken him.
After a brief period of Stage 4 sleep, and to prevent us from falling into a deep coma, our brain partially arouses us: Our brainstem, the most primitive part of our brain, stimulates the higher levels of our brain with random impulses and returns us to Stage 2 sleep, associated with REMís and dreams. We stay in the REM dream stage for a while and then again return to deeper stages.
As the night progresses, Stage 4 levels become more and more shallow. This cycling between Non-REM deep-stage sleep and REM low-stage sleep, repeats several times every night while we are asleep. We are fluctuating between dreamless periods of deep sleep and periods of light sleep, sustained by dreams.
There is no substantiated report of a human being functioning without sleep indefinitely. Experiments with humans and animals have shown that it is possible to survive without sleep for approximately ten days. If we deprive a person of sleep by constant stimulation, he will eventually succumb to sleep. He will then sleep and he will feel fully restored upon awakening, without any permanent damage.
This situation is analogous to starvation: Food deprivation, even to a skeletal stage, is readily reversible by the introduction of food and will normally not result in any permanent injury. The need for sleep varies from person to person and depends on age. Young persons require slightly more sleep than elderly persons do. The range of normal sleep for humans ranges from five to ten hours, with a median in the 7 1/2 hour range.
Several theories try to explain why most animals, including humans, have a compelling need for sleep. One theory describes it as a mere a habit, without biological foundation. Creation-based theories attribute the existence of man and all of his needs, including the need for sleep, to a superior being. Another theory refers to sleep as a state of exhaustion, requiring restoration of bodily functionality.
Whenever we try to determine why human beings do whatever they are doing, we must remember that human beings did not develop overnight. Human beings are the product of billions of years of evolution. Certainly, no superior being created man and then decided that man had to waste half of his life in a state of stupor.
If we search with sufficient persistence, we will always find an evolutionary explanation for all human behavior. All human physiology and behavior is attributable to the process of evolution. There is no other rational explanation for human behavior.
A search for a plausible explanation of the need for sleep will take us back millions of years, long before humans entered the scene. We need to go back to periods when living organisms first became aware of light and evolved sensors for visually perceiving the difference between night and day, between darkness and light.
Evolution rewarded organisms that had the ability to perceive visual impulses with a greatly enhanced ability to survive. The visual perception of objects greatly enhanced the ability of such organisms to survive by preying on other organisms that lacked these faculties.
About 2.5 billion years ago, one billion years after the inception of life on earth, many animals had developed the ability to utilize daylight in order to survive. The competition in the food chain became intense during daylight hours. However, at night when there was no light energy to activate lights sensitive cells, most animals were at a disadvantage.
The most efficient way of coping with the lack of light was to reduce exposure by lying still and keeping very quiet. Animals that utilized such imposed periods of inactivity to restore their physiological systems, gained a further survival advantage: They were in better condition to pursue prey when the sun rose again.
Another incentive to remain motionless in a safe and secluded place was the difficulty of moving around in darkness. Animals, including the ancestors of humans, who insisted on moving around at night, risked falling off cliffs or into holes. They also exposed themselves to forms of life that had never developed any sensitivity to and dependency on light.
Insomniacs also were in danger from animals that had specialized in hunting at night and had therefore evolved high susceptibility to light. Such night-predators, such as the precursors of owls or cats, were able to see when other animals could not. If other animals are stalking you and you cannot even see them, your best course of action is to remain immobile and very quiet: You enter a state of semi-consciousness, you sleep.
Over billions of years, the process of evolution favored animals that slept at night. In doing so, they prevented injury to themselves, avoided falling prey to specialized predators and they gained the opportunity to restore their bodily functions. Thus, animals achieved the ability to sleep and rest at night.
However, in the event of a disturbance by predators, this period of semi-consciousness demanded the ability to restore, instantly, full operational control over the body. Therefore, animals benefited from the ability to sleep and rest during the dangerous and unproductive periods of darkness.
While benefiting from sleep, animals also had to develop a mechanism that prevented them from falling into a deep coma while asleep. It was vitally important that some neural systems remained partially active and that the body could be re-activated instantly.
Dreams are the evolutionary response to this need. The most expeditious way of letting an animal rest quietly, and thus safely, was to shut down most perceptions, such as vision. However, sleep also had to provide for instant awakening in the event of loud noises that might be a warning of large predators stumbling around in the darkness.
Animal brains accomplished this feat by selecting those organisms for survival that developed the means to stimulate the brain at intervals in order to prevent it from succumbing to a comatose sleep. We do not shut off an automobile engine if we anticipated its use in the near future. Therefore, we allow an automobile engine to idle, to let it tick over very slowly, ready for instant acceleration.
Thus, evolution enhanced the survival of organisms that were able to generate random impulses in the brainstem, the most rudimentary part of the brain that never sleeps. Such random impulses triggered complex responses in other areas of the brain, without fully engaging and awakening the brain as a whole. In animals, including human beings, dreams caused by random impulses in the brainstem, punctuate sleeping patterns. Dreams provide sufficient stimulation to prevent the rest of the brain from falling into a dangerous stupor during which an animal would be completely unaware of looming hazards.
A coincidental advantage to maintaining the brain in a balance of dormancy and preparedness is the resulting ability of the body to restore the vitality of mental and physical functions. Both body and mind refresh and restore themselves to new vigor after a good night of sleep.
Just as there is an absolute need for sleep in all but the most primitive of animals, all animals must dream because dreams are an essential part of the sleep cycle. Dreams are just as essential as sleep because dreams prevent regular sleep, with its ready accessibility to wakefulness, from slipping into a comatose state. Dreams are the mechanism to keep our physiological perception machinery in a state of semi-alertness, while remaining safe and quiet and while restoring our physiological and mental resources.
We can observe dreams in animals when we are watching a sleeping dog or cat. Their twitching extremities and flickering eye movements clearly indicate periodic brain activity. The same mechanism applies to humans: While we are in a dream state, our legs may twitch but we cannot move them. During deep sleep, such as Stage 4 Sleep, our brain actually paralyzes our legs.
The obvious reason for this reaction can be readily deduced from the need to lie quietly but remain semi alert. An animal, thrashing around in its dreams, would soon attract predators. Such uncontrolled motion might also result in physical injury. Eons ago, evolution has eliminated all animals, including humans, who do not exhibit safe sleep and dream patterns.
There may be more profound explanations dealing with the nature of sleep and dreams but, according to Occamís Razor, the simplest explanation is the one most likely to be correct.
The Interpretation of Dreams
Due to space limitations, sections in Red are accessible only in the Book or CD "How Life Really Works".
In order to be successful in our goal of achieving happiness, we must see Objective Reality as clearly as possible. Persons who have a distorted view of reality are bound to incur conflicts in dealing with reality. They will thus find it difficult to achieve lasting happiness.
There is nothing mysterious or threatening about sleep and dreams because both attributes are hard-wired into the human brain and body by billions of years of evolution. Sleep is nothing but a survival mechanism to prevent us from falling off cliffs and from being devoured during diurnal periods of darkness.
Sleep also serves to rejuvenate and restore many of our physiological and brain functions and allows us to face every new day with optimized mental and physical resources. Dreams are essentially the random firings of part of our brain and are necessary to keep us in a state of semi-alertness while we are sleeping. Dreams may also serve to reactivate and refresh our physiological systems.
Unless dreams become very repetitive or frightening, such as very frequent nightmares dealing with similar subjects, it is fruitless and confusing to attempt any interpretations of our dreams. The random firings of our neurons do not follow normal neurological pathways.
If we are determined to find the root of psychological difficulties by reference to our dreams, the corresponding psychoanalytical process is very lengthy and may have very questionable results, if any. We also need to be aware of pseudo-scientific charlatans who can only offer arbitrary interpretations of our dreams, while using this process to part us from our money.
For a happy life: Sleep as soundly as you can, forget your dreams and, above all, do not allow your dreams to influence or impinge on your everyday existence.
Copyright © Walter E. Requadt All Rights