DREAMS AND NIGHTMARES
PART OF A SELF-ALARM SYSTEM FOR A SLEEPING BRAIN
Copyright © 1987
ABSTRACT: Based on the correlation of the author's own dreams to the state of his body immediately after awakening from a dream scenario, this paper proposes that the function of dreams and nightmares during sleep is: a) to wake up the sleeping brain, at least for the purpose of changing frequently the position of the body tired under the influence of gravity for better relaxation, and b) under adverse conditions, to fully alert the brain to take control of the body to defend itself. The author believes that dreams and nightmares constitute an essential part of a self-alarm system needed by a sleeping brain.
Everyone dreams. It is reported that even the unborn baby dreams as do other mammals (1, 2). Varying roles have been attributed to dreaming and I have tried to summarize some of them below in this text. However, scientists so far have not been able to understand the real purpose of sleep or the dreaming during sleep in human biology.
Throughout human history, interpretations of dreams have played a very important role in the lives of human beings. People have made important decisions based on what they saw in their dreams and have accordingly influenced not only their own lives but also the lives of many other people. Some people have declared themselves as prophets or representatives of God or even God itself and hence have founded religions based on their dreams.
Some dream scenarios are pleasant while others may be terrifying to the dreamer. Some dream scenarios are so bizarre that they almost appear to be supernatural in character and yet have never been experienced or learned indirectly by the dreamer. Close examination of what can be remembered about the dream immediately after awakening from a dream scenario indicates that the following aspects are common to all dreams:
People have always asked questions regarding dreams. What are dreams? Why do we dream? What meaning should be attributed to a dream scenario? Do dreams carry any messages about the past, present and future of the dreamer? What is the mechanism that generates dreams and many more? Many researchers have put forward theories aimed at answering such questions and also about the function of dreaming. Some of the theories expressed by prominent authorities are summarized below.
Sigmund Freud was one of the dream researchers who is most celebrated in the western world. In his "The Interpretation of Dreams", (1), Freud puts forward a dream theory in which he proposes that the function of dreaming is to act as guardian of sleep and also as a means of "wish fulfillment" for the oppressed wishes. He says that the driving forces for dreams are the repressed wishes that are formed from experiences that the dreamer has had during the day or at other times. Freud attributes meanings to scenes and characters seen in dreams and tries to decode the inner world of the dreamer by using these assumed meanings. Modern research about dreaming does not support Freud's dream theory.
Freud, before proposing his own theory of dreams, discusses theories put forward by other researchers before or contemporary to him. Accordingly, Freud classifies the sources of dreams into four categories, (1, page 27). They are:
1) External sensory (objective) excitations,
2) Internal sensory (subjective) excitations,
3) Internal (organic) somatic stimuli, and
4) Purely physical sources of stimulation.
Ernest Hartmann summarizes his views on function and dreaming as follows, (2,3):
"Dreams consist of images that include memories of experiences connected with important feelings of the dreamer. These images are both a way of representing the feelings and experiences with which they are connected, and a way of organizing them so that they can be meaningfully integrated by the dreamer. This integrative process is usually more or less successful but when it is not, the dream may be only a representation of the problem without any integration or solution. The classical psychoanalytic view of dreams is not really contradicted by this approach except for the idea of drive discharge. As in the traditional view, dreams are meaningful, contain material related to past unsolved problems or conflicts, and are thus the source of understanding of the patient. They are important to psychological function, however, not as a vehicle for satisfying unfulfilled or forbidden wishes, but because they provide a mechanism for maintaining a continuity and meaningfulness in our life experiences, allowing us to draw on past experiences to modify old modes of behaviour."
Berger (4) refers to the following theories regarding the function of dreaming, which is also known as Rapid Eye Movement (REM) sleep:
The Ontogenetic Theory
Proposed by Roffwarg, Muzio and Dement (5), the theory suggests that REM sleep provides endogeneous afferent stimulation necessary for structural differentiation and maturation of the central nervous system during fetal and neonatal life, when brain growth is maximal. The high percentage of time spent in REM sleep in both the premature and full-term newborn mammal and its subsequent decline with increase in age has been presented as the principal evidence for this theory.
The Phylogenetic Theory
This theory proposed by Snyder (6) suggests that REM sleep first evolved in the mammal to serve a "sentinel" or vigilance function necessary for survival from attack by other species. Snyder suggested that REM sleep provides periodic cortical arousal throughout sleep preparatory to the brief awakenings which usually terminate REM periods, so that the animal has sufficient 'critical reactivity' to adequately 'test' the environment for dangerous elements.
The Homeostatic Theory
This theory proposed by Ephron and Carrington (7) suggests the existence of a homeostatic interplay between REM sleep and non REM (NREM) sleep to account for the sequential relationship seen between these two sleep states. They proposed that the loss of cortical 'tonus' or 'vigilance' during deep NREM sleep provides the organism with needed rest, and must be maintained within adaptively appropriate limits. In order to preserve the continuity of sleep, but maintain the level of cerebral excitation within these limits, Ephron and Carrington suggested that REM sleep serves the function of periodically increasing cortical 'tonus'.
The Oculomotor Innervation Theory
This theory proposed by Berger (8) himself suggests that REM sleep provides a mechanism for the establishment of the neuromuscular pathways involved in voluntary conjugate eye movements in both phylogenesis and ontogenesis; and that throughout mammalian life REM sleep furnishes periodic innervation of the oculomotor system during extended periods of sleep, in order to maintain facilitation of binocularly coordinated eye movement into subsequent wakefulness.
Francis Crick and Graeme Mitchison have recently proposed a radically new role for dreaming, (9). Quoting from New Scientist (10), the theory, in summary, says that "during dreams the brain is eliminating or 'unlearning' spurious patterns of activity in the cerebral cortex (the part of the brain concerned with thinking), in order to maintain its efficiency as a mechanism for the storage and retrieval of information. Cortical cells are interconnected in complex, overlapping networks, so that if one cell fires, others will also be excited in consistent patterns. Crick and Mitchison suggest that these patterns are the basis of memory. Computer scientists have developed models of such networks that are capable, like the brain, of 'learning' new information. Having learned, they can always produce an appropriate reaction to that information when they encounter it in future. Unlike conventional digital computers, these models store information in terms of the strengths of the various connections between cells in the network, or of the firing thresholds of the cells. These are not fixed at the outset but can be adjusted through 'training'. With adequate training, a model network will produce an appropriate response even when given only part of the original input. A single network can store many associations in this way. However, if it becomes overloaded it ceases to perform efficiently. It may produce 'fantasies' or 'hallucinations' - undesirable patterns of activity that Crick and Mitchison call "parasitic modes of behaviour". They suggest that if the real brain is anything like the theoretical model, such parasitic modes are bound to arise frequently during an individual's lifetime and that the brain must have evolved some way of eliminating them.
The purpose of this paper is not to dwell on the interpretation of dreams but, rather discuss the role of dreaming during sleep. Particularly from the point of view that a sleeping body needs a security system for the survivability of the species during sleep.
In this paper, I present my view regarding the brain's need for sleep. I also propose a new role for dreaming which, I believe, has not been considered before and is the most likely explanation of the purpose of dreaming and nightmares in the biology of human and other mammals. The proposed role for the dreaming is based on observations of many of my own dreams.
I present my view regarding the function of dreaming during sleep for humans and other mammals who have adopted sleeping as one form of living through evolution.
The method of analysis which I used to capture some of the dream scenarios and their relation to the position of my person at the moment of waking up is also outlined in the text.
Various questions related to dreaming and sleep are discussed in the text in view of the presented dream theory.
A summary of the presented view and a list of references used in this study are given at the end of the paper.
2. BRAIN'S NEED FOR SLEEP
It appears that one of the design principles being used by Nature is that the organism be self sufficient to the capacity of its basic structure after it has gone through its growth period. Although limited help for a limited time may be provided by the parent organism, the new member of the species must be on its own in all aspects of its life in the struggle for survival. Nature probably never intended to have doctors, psychologists, social workers, etc. to help the struggling member of each creation to sustain its life.
A living organism is a 'machine' based on living organic components, the building blocks of which are the living cells.
All machine systems, whether based on organic or inorganic components, need maintenance after some duration of operations. There is no machine system that works indefinitely. Any machine operated continuously long enough will eventually break down and become inoperative. In order to prolong the useful life of a machine system, it must be maintained. Carrying out regular maintenance on a machine system helps it to operate in the way it was designed to operate and give the service that is expected of it. The maintenance of the machine may be in terms of preventive and corrective maintenance.
Corrective maintenance on a system implies that the system has already reached a state in which normal functions of the system cannot be carried out. Once the system breaks down due to partial or complete failure of one or more of its components as a result of continuous operation of the system, then, corrective maintenance, involving repairs and/or replacement of components and/or subsystems, may have to be carried out in order to restore the broken down system to its normal operational state. Corrective maintenance may be carried out at the molecular and cell level of organisms.
Partial or complete breakdown of a 'machine' system (such as a living organism) must be avoided so that only the minimal amount of corrective maintenance is performed. This is an essential requirement, since during such activity, the organism is most vulnerable to aggressive elements that may attack the body from both the external and internal environments. The organism is incapacitated to the degree that it is unable to carry out some of the normal defense functions needed for its survival. Hence, it is at the mercy of its environment where other living organisms are ready to take advantage of the situation and devour the incapacitated organism for their own survival.
Regular preventive maintenance prolongs the useful life of a machine system between system breakdowns. Particularly in living organisms, the "breakdown state" must be avoided for as long as possible, since it is quite likely that such a state would lead the organism to its death. It would be in the best interest of the living organism if its bio-system allowed for regular and self-applied preventive maintenance of itself in order to avoid situations requiring corrective maintenance, particularly at levels higher than the cell level.
Among the two types of maintenance, corrective maintenance is much more costly in terms of energy, time and skills as compared to preventive maintenance. Hence, preventive maintenance should be the preferred mode of maintaining bio-systems. For example, consider the self-healing and replacement of components (i.e., the regeneration of parts of the brain and the body). Such corrective maintenance would require not only comparatively more energy and skills (specialization) but also a longer time to complete the process of self replacement and repair.
It may be that one of the objectives of Nature as applied to living organisms is that the structure of the living organism must not allow system breakdowns due to its own functions (operations). In other words, the preventive maintenance must be the preferred rule rather than the exception for self survival. All functions of the body must evolve around this underlying principle.
If this principle is in fact being used in real life for sustaining the normal functionality of a living organism, then, built into the system, there must be time allowance for doing preventive maintenance on the system. In human beings, mammals and other organisms which sleep, this function is probably carried out mostly during sleeping.
As human beings, we are able to observe a feeling of relaxed body and mind, freshness and rejuvenation after sleep. These feelings seem to be the indication that some maintenance is taking place during the sleep mode.
It is most likely that the presence and absence of light on a cyclical basis, (i.e., day and night on Earth) caused the "sleep mode" to evolve for the higher order organisms (such as birds and mammals) as part of a self performed preventive maintenance system. Turning off the brain's and body's daytime functions during sleep (for at least one third of the day) is itself a form of preventive maintenance. By not operating continuously, the brain prolongs its own and the rest of the body's life.
Negative feelings and mental and physical stresses build up during the waking life of a higher order organism (such as a human being) due to interaction with the environment for survival. The effects of stress and negative feelings on the body and brain are upsetting and disruptive. They help to speed up the breakdown of the organism's normal functioning, probably by disturbing the body's immune system. It would, therefore, be a natural requirement that such feelings and stresses be inhibited from influencing the immune system of the body so that it can effectively perform its function of defending the organism. This is an important preventive maintenance measure that seems to be performed best during sleep.
Being "self sufficient" is probably one of the most important objectives for most of the living organisms. In a normal and healthy body, time must be reserved in order to get rid of the built up tensions and depressions without being coached by others. This is important for the survivability of the species. In fulfilling this requirement, the brain (being the central information processing, evaluating and controlling center of the body) must be responsible for carrying out the preventive maintenance (self healing) functions on the organism.
In view of these considerations, it may be assumed that "sleeping is required for the self maintenance of the brain and the body".
Brain cells are not regenerated nor is any abnormality in the brain (and in its communications system with the rest of the body) readily self corrected by the use of corrective maintenance. In view of this situation, the brain cells must be made to serve longer by preventive rather than by corrective maintenance. It seems that this is probably what is taking place in the brain. The brain goes to sleep regularly, probably as a preventive maintenance measure, to prolong the life of the brain. During sleep, preventive maintenance in many forms may be taking place at the cell and/or molecular level. In time, the nature of the self-performed preventive maintenance during sleep will eventually be understood and defined by scientists.
In living organisms that sleep, the self-performed preventive maintenance on the brain and the rest of the body may be in the form of:
3. BRAIN'S NEED FOR A SELF-ALARM SYSTEM
The human body has been provided with a very extensive sensing and communication system that is used primarily as the "alarm and control communications network" needed for the survivability of the body. Various sensory systems located throughout the body provide the means to detect signals coming from the external world and from within the body, while the body is awake. The detected signals are transmitted to the brain where they are processed and evaluated whereupon relevant commands are transmitted by the brain to the particular organs of the body so that the desired actions may be carried out. In a healthy and undrugged body, this is an ongoing process while the body is awake.
One third of our lives is spent in sleep. In this state, the brain seems to acquire a state of unconsciousness during which it does not respond to stimuli at levels it would normally respond to while the body is awake. Hence, the sleeping body is exposed not only to many dangerous conditions that may exist in its immediate external environment, but also to possible harmful situations created by the body's own physical, physiological and psychological states, i.e., stresses existing at that time. Even though most parts of the body are relaxed during sleep, some parts may become highly stressed - that is, driven to the level of discomfort by the body's own weight (i.e., under the continuous effect of gravity or by other prevailing conditions that are external or internal to the body such as the need to go to bathroom). If the brain does not wake itself up from the sleeping mode, the body could do itself irreversible harm. It is clear that a human body or any other mammal or organism which has adopted to sleeping as one form of living must have a self-alarm system capable of waking up the brain during such hazardous conditions.
It seems that Nature, through evolution, has indeed provided a self-alarm system for the human brain and for other mammals that sleep. I believe that part of this self-alarm system of the brain is manifested in the form of "dreaming" and "nightmares" during sleep. I reached this conclusion after observing, almost on every occasion that I could analyze, the presence of a very close correlation between my own dreams and the condition I found myself in at the moment of waking up.
During the dreaming mode, all kinds of dream patterns are generated. These patterns may address combinations of all the sensory systems of the body. Most of these dream patterns seem to be lost immediately upon waking up. Visual scenarios of dreams are particularly susceptible to light. They fade away quickly on opening the eyes in a lit environment.
Some of the dream and nightmare patterns generated during dreaming seem to be related to the effects of the external and/or internal conditions causing discomfort at that time, especially to the last few seconds that cause the awakening of the brain. For example, a part of the body may become numb due to a blocking of blood circulation caused by the body's position during sleep. Body sensors, associated with the area having discomfort, signal the situation to a part of the brain, probably the cerebellum, which may be acting as the "watchdog" of the brain while the brain is asleep. I propose that such a part of the brain acts as the "Sleep-Time Operations Center" (STOC) for the total body. The STOC probably uses the incoming signals to induce dream patterns or scenarios which in turn stimulate the brain to change from "sleep" mode to "awake" mode. In this transition, the brain becomes awake for a short time, but long enough for the brain to send the necessary commands to the body to change its sleeping position and/or to eliminate or reduce the discomfort. The brain may then resume its sleep mode once again or stay awake for a while. This can occur frequently during sleep.
It seems that the severity of discomfort experienced by the body or the seriousness of the threat to the body leads the dream scenario into a nightmare scenario from which the subject wakes up in an agitated state. Particularly, the presence of situations, where any part of the neck and/or head are physically threatened during sleep, are observed, almost with certainty, immediately after awakening from a dream in which one sees himself being threatened. In these situations, the dream scenario is invariably far less than pleasant.
For instance, the blockage of circulation in the neck area in one sleeping situation and in the hand area in another do not have the same degree of severity for the body. In the first case, prolonged sleeping in that condition can be detrimental to life. One could end up with self strangulation. In the second case, the worst that could happen may be to cause permanent injury to the hand. Although both situations lead into nightmares, the dream scenarios induced by physical threats to life support systems (such as breathing and blood circulation to the brain through the heart and neck) seem to be highly violent in nature and terrifying to the brain. Such situations can readily arise by having, for example, a bedding material wrapped around the neck tightly. Conditions like this seem to invariably cause frightening dreams from which the brain wakes up suddenly and in an agitated state. Because of the frightening aspect of the dream scenario, the brain becomes fully alert after waking up from the nightmare and does not go back to sleep for some time. Attaining this extra alertness from the brain seems to be a requirement that Nature demands for the survivability of the sleeping brain and hence of the species. It is a way of ensuring that the brain becomes fully awake and alert in commanding the necessary bodily actions to take place in order to alleviate the impending physical danger to the body.
4. METHOD OF ANALYSIS
In my research, the method of analysis involved relating the dream scenario to the physical and/or physiological conditions that I found myself in, immediately after awakening from a dream. The state of the body during dreaming and the dream scenarios seem to be related to each other, particularly, the dream scenario that causes the awakening. To achieve any correlation between the two events, it is important to remember the dream while trying to retain and observe the external and internal conditions of the body as soon as one wakes up from dreaming. Quite often, this is difficult to do since it seems that the brain, almost automatically, commands the body to change its position upon awakening. The observer does not always remember that he/she wanted to analyze the situation. Normally one tends to go back to sleep after changing sleep position. Yet, to do a situation analysis one needs to stay awake and, without disturbing the physical state of the body, observe the body's state and the environmental conditions influencing it at that time. Therefore, one has to make special effort so that a good opportunity is not missed.
5. SLEEP-TIME OPERATIONS CENTER FOR THE BRAIN (STOC)
If the brain must sleep, and this seems to be a mandatory requirement, then for the purpose of self maintenance and/or some other reason, there must be a back-up system which ensures the survival of the brain and body while the brain is asleep. The back-up system can be in the form of a duplication of the brain itself or a lesser system. Similarly if the brain must sleep and at the same time maintain "motor control capability" on the body, then the back-up system probably has to be as complete and as complex as the main system. This would mean having a second brain so that while one is sleeping, the other brain tends to the needs and requirements of the sleeping brain as well as the rest of the body.
However, if the brain must sleep and yet does not need to have the "motor control capability" on the rest of the body (in other words the body may assume the so called "sleep paralysis state" while the brain is sleeping) then the back-up system does not have to be as complete and as complex as the main brain is - as long as the back-up system has the capability to:
In the first model we have a duplication of the master control system. In the second model we have a master control system and a "Sleep-Time Operations Center". The second model, as an optimized design, would need less energy for its operations and maintenance than the first model. In time, the nature of the STOC and the way it works will eventually be defined by neuroscientists.
The STOC would take charge of the body while the brain is asleep. During sleep, information from all sensors (both outside and inside the body) would be sent continuously to the STOC. Such data would represent the monitored environmental conditions and their influence on the sleeping body at that time.
I consider that one of the main functions of the STOC would be to act as the guardian of the body while the brain is sleeping and to wake up the sleeping brain when needed. This function would be carried out by the STOC when the sleep time discomfort level of various parts of the body, as represented by the signals coming from the sensory systems, exceed the stress threshold limits set for such signals.
6. SLEEP PARALYSIS
The so called "sleep paralysis" means that parts of the body cannot be moved while the brain is asleep. I see this as insurance, designed by Nature and perfected through evolution, to prevent possible harm that a sleeping body could cause itself if it moved during sleep.
As the brain goes to sleep, the Sleep-Time Operations Center of the brain takes over the function of guarding the body and waking up the sleeping brain when needed. It seems Nature has made sure that the STOC need not have "motor control capability" over the muscle system of the body. This is in harmony with the self preservation principle of the body and also explains the "sleep paralysis" state. For early man who may have slept in a cave or in the top of a tree, body parts such as the head, arms and legs that moved energetically and in an uncontrolled manner under the influence of a violent nightmare condition, could readily inflict severe if not fatal injuries to the body while the brain is asleep. The objective of the STOC in guarding the body must be to awaken the brain first so that it becomes fully alert, takes full control of the body, assesses the situation and then takes the necessary motor action in order to reduce and/or eliminate the danger or discomfort applied to the body at that time. In this model, the STOC tries to wake up the brain by inducing "dreaming" or the REM sleep.
In real life, each individual learns about many events by means of direct and/or indirect experience. The nature of all of these events may range from being most pleasant to most terrifying. It may be that such events, when they are being learned, are graded by the brain with special regard to their terrifying effects. Those events which are most terrifying in nature to a person are remembered for a long time indicating that they are stored in the long-term memory of the brain to be used later in dreams when the survival of the self is threatened during sleep.
During sleep, when the body is subjected to potential life threatening situations, dream scenarios are generated and eventually converted into nightmares by the STOC. It seems that the STOC is capable of evaluating the potential threat to the body from the prevailing environmental conditions and making judgments about them based on the signals coming in to the STOC from different parts of the body. Accordingly, the STOC probably accesses, from the memory system, data representing some of the previously learned terrifying events as appropriate to the incoming signals and uses them in generating nightmares.
One Very Important Starting Condition of Nightmares
It has been my continuous observation that during sleep when the nasal passages get blocked due to the degree that one cannot breath and the oxygen intake to the brain is then reduced to a dangerously low level, the sleeping brain will go first into dreaming and then nightmare mode in every case. As the level of oxygen to the brain decreases, the brain's self-alarm system forces the sleeping brain to wake up via the dreams and nightmares. I have observed this over and over again. It seems that when the person is a through the nose-breather as I am during sleep, the majority of nightmares are caused by the blockage of nasal passages. In my own nightmare experiences, I have discovered that my nose is blocked to the degree that I can hardly breath. This is probably a condition that millions of people experience throughout their life but yet attribute such nightmares to unrelated causes. I believe the conditions that induce nose blockage during sleep and thereby cause nightmares, should be investigated thoroughly by sleep scientists. Solutions that prevent nose blockage during sleep could save a lot of sleepless nights for many people. Repeated interruptions of the deep-sleep mode, with short durations of sleep, seem to be the most tiring and nerve wracking conditions that could or should be avoided.
My observations regarding nightmares are summarized below:
8. WHY DREAMS ARE ALWAYS DIFFERENT?
In each sleeping period, the dreams dreamt by people are different from the previous ones. Why is this?
The fact that all dream scenarios differ from each other may be due to Nature's need for a credible self-alarm system. If we had the same dream patterns every time, the brain could get used to seeing them and ignore them.
The signals coming from various parts of the body represent real situations which may or may not be life threatening. They eventually become sources of discomfort for the sleeping body. However, they must not be ignored based on the assumption that they represent unimportant situations. If the STOC treats the incoming messages as unimportant and ignores them, it will eventually jeopardize the survival of the sleeping brain and body. Therefore, such a situation must never be allowed. Every incoming signal must be evaluated on its own merit and graded in accordance with the severity of the threat that the situation poses to the body. Each condition, being external or internal to the body at that time and influencing the body while the brain is asleep, must be treated accordingly as a dream scenario which may range from being a pleasant one to a nightmare.
In real life, a security system is expected to be credible. An alarm system without credibility is not a believable system. Alarms from such a system are regarded as "false alarms" and are therefore ignored. Like a real life security system, the self-alarm system for a sleeping brain must also be credible. For the survival of the body, Nature cannot afford to consider an incoming stimulus to be due to a false alarm condition and thus ignore it. Nature must ensure that false alarm assumptions are never made by the STOC. In order to guard the brain and the rest of the body against all possible life threatening conditions during sleep, the brain's self-alarm system must always generate credible alarm signals. In other words, a different dream scenario must be generated for each case even though the stimulus may be the same. The same dream scenario must not be presented over and over again so that the brain gets used to seeing it and starts ignoring it.
For example, Hildebrand's three alarm clock dreams (Ref 1, p.27-28) where three different dream scenarios were caused by the same stimulus can be explained by the "credibility requirement" that Nature must have applied to the "self-alarm function" of dreaming.
9. DO WE HAVE A SIXTH SENSE?
Some of the dream scenarios described in Freud's Interpretation of Dreams also brings this question to mind. For example, in the so called "Three Alarm Clock Dreams" of Hildebrandt, (Ref. 1, p.27-28), it seems as if some sensory system was watching the alarm clock all the time. As if his dreaming and the "ringing of the alarm clock" were synchronized. This kind of "synchronized" waking up with an alarm clock has also been experienced by this author.
A similar situation in Maury's dream, (Ref. 1, p.26-27) is also noted where he sees himself "being beheaded". As he wakes up from his dream, he finds that the top of his bed had just collapsed and he was hit with it.
It is again very curious to find that the imminent collapsing of the top of his bed was sensed by some sensing system (associated with the body) which then translated that event into a dream scenario.
The unavoidable question is: "how this event, i.e., in this case the collapsing of the top of the bed, was sensed before it happened?". Do we have a sixth sensory system that works only while we are asleep?
If indeed there were such a sensing system which works during sleeping only, it would not be an easily noticeable or self evident system. On the other hand, being "self evident or easily perceived" would not be the prime objective of such a sensory system. Its prime objective would probably be to act as an early warning aid to the sleeping brain from an impending dangerous situation. In the life of early man, such a sensing system would be invaluable since he/she would be sleeping outdoors, in caves and/or on tree tops. Modern man sleeps in relatively very safe quarters. The utilization of such a system may not be very frequent and, hence, detecting its presence may be elusive.
10. REM SLEEP OF GIRAFFE
During dreaming, Rapid Eye Movements, normally referred to as REM, are observed in sleep research subjects. The REM sleep may be considered as part of the transitional state during which the brain is being excited by the STOC to wake up from the sleeping mode so that it gains sufficient consciousness to eliminate the disturbance to the body by changing its sleeping position or by altering the environment. During dreaming, the eyes are probably responding to the feedback signals from the visual scenes of the dream scenario and also from following the dream pictures.
REM sleep has also been observed in other mammals, (11). For example, frequent REM sleep has been observed in sleeping giraffes. During sleep, the giraffe rests its head on its own body by bending its neck. Frequently, following REM sleep, the giraffe wakes up, changes the position of its body and neck, and then goes back to sleep. Surely, a sleeping position in which the neck is bent almost 180 degrees from its normal position is not expected to be a comfortable position. In this position, possible constraints in the blood supply system to the brain can take place and, hence, result in the observed frequent REM sleep.
11. NO REM SLEEP OF BOTTLE-NOSED DOLPHIN
An interesting exception is the sleeping mode of the bottle-nosed dolphins (11). This mammal seems to have developed a special sleeping feature such that during sleep only one cerebral hemisphere is sleeping at a time while the other remains awake. These roles are reversed after about an hour. The sleep is reported to be mostly deep sleep and without apparent signs of REM sleep. With such a sleeping feature, it is not surprising that REM sleep is not observed on bottle- nosed dolphins. Since one side of the dolphin's brain is always awake and, therefore, its main alarm and control system always active and functioning, there is no need for the brain to have a secondary self-alarm system such as dreaming.
12. WHY DREAMS ARE NOT REMEMBERED?
Most of the time, dreams are forgotten by the majority of people after they awaken from their dreams. Normally one will not remember them unless one pays special attention to remember them. Even with special attention directed to remembering dreams, one can remember only some very prominent features of them. The question of "Why do we not remember dreams?" may be explained as follows:
If the function of dreaming is to wake up the sleeping brain under adverse sleeping conditions, once the dreaming has achieved this objective, then its function stops for that sleeping period. After this purpose has been achieved, there is no need for the brain to remember the dream details. If we remember some parts of some dreams, it is simply a redundant after effect that is not required for any aspect of the body's survival. Essentially, Nature must have intended that the dream contents of each dreaming period be used "one time only". Once the dreaming has carried out its function of waking up the sleeping brain, the dream signals are readily erased or replaced by background noise signals such as the light and sound signals in the sleeping environment.
For example, it is important for a baby to dream, yet it is not important to remember the contents of the dream. During sleep, a helpless baby dreams to wake up from conditions which affect him/her adversely. After waking up, the baby moves parts of his/her body, i.e., arms, legs, head, etc.. If these actions are not sufficient for the baby's comfort, the baby cries to attract the mother's attention so that conditions affecting the baby adversely can be corrected by the mother.
Like dreaming, the "crying" after waking up from some dreams or nightmares is also part of the self-alarm and defense system of the baby's body. Both the dreaming and crying carry out their intended functions - which are to awaken the sleeping brain under adverse bodily and physical conditions and to call for mother's help in order to insure the survivability of the body. After this objective is achieved, there is no need to remember what the dream contents were or why the baby cried.
People dream when there is a need to wake up. The movements of sleep subjects during night long sleeping have been recorded. When one watches such visual recordings, one sees that the sleep subject does a lot of turning and twisting during their sleep. This is so with everyone. Most of the movements seem to be associated and are preceded with dreaming. The sleeping brain wakes up to correct the discomforting situation by commanding the body as a whole or parts of the body to move in a desired way and then goes back to sleep. The function of dreaming for this portion of sleep has been achieved. The next section of sleep gets its own dream scenario.
13. FETUS ALSO DREAMS
It is reported that the fetus also dreams (11,12) in a mother's womb. This is indicated by the REM observed from the fetus. A mother's womb may be the most secure place for an unborn to be in but it may not necessarily be the most comfortable place. Particularly since the mother's physical and psychological health (stresses) affects the baby's comfort and physical well being. The unborn baby has to defend itself continuously against any adverse condition created by the mother's activity. If the fetus is sleeping, dreaming wakes up the sleeping brain of the fetus; the brain activates movements of the baby's limbs which in turn cause sensations in the mother. If the mother is not sleeping at that time, she consciously or unconsciously corrects her own position. However, if the mother is also sleeping at that time, the fetus's activities within the mother's body would induce dreaming in the mother's sleep and cause her to wake up and correct the situation thus relieving the baby's predicament in the mother's womb. Nature seems to have provided a self-alarm and self-defense system for the unborn baby to take care of itself even in the most secure space within the mother's body.
A host of roles and interpretations have been attributed to dreaming while asleep. Hopefully, research in this field will eventually give us an insight into the real role that sleep and dreaming play in our lives. Meanwhile, I wish to share my observations with sleep researchers and propose the theory that dreaming during sleep, which may be in the form of ordinary dreams and nightmares, is an important part of the brain's self-alarm system needed by the brain in order to secure its own survival and also the rest of the body's survival against possible harm that may be created by the body itself during sleep, gravity and/or other external environmental conditions. It seems that dream scenarios are generated by a part of the brain which I call the "Sleep-Time Operations Centre". This part of the brain may have the function to early-warn and wake up the brain against impending situations which may be harmful to the body if the brain continues to sleep under the prevailing conditions.
In addition, this paper also proposes the view that:
1........ S. Freud, "The Interpretation of Dreams", Basic Books, Inc. Publishers, New York.
2........ "Sleep, Dreams and Memory" edited by William Fishbein. SP Medical and Scientific Books, New York, 1981.
3........ Ernest Hartmann, "The Functions of Sleep and Memory Processing", Chapter 7 of Ref. 2.
4........ Dreams and Dreaming Selected Readings, Edited by S.G.M. Lee and A.R. Mayes, Penguin Education Books.
5........ H.P. Roffwarg, J.N. Muzio and W. Dement, "Ontogenetic Development of the Human Sleep-Dream Cycle", Science, Vol. 152, p. 604-619, 1966.
6........ F. Snyder, "Toward an Evolutionary Theory of Dreaming", Amer. J. Psychiatry, Vol. 1234, p.121-142, 1966.
7........ H.S. Ephron and P. Carrington, "Rapid Eye Movement Sleep and Cortical Homeostatis", Psychological Review, Vol. 73, p.500-526, 1966.
8........ Ralph J. Berger, "Oculomotor Control: a possible function of REM sleep", Psychological Review, Vol. 76, p.144-164, 1969
9........ Francis Crick and Graeme Mitchison, "The Function of Dream Sleep", Nature, Vol. 304, p.111-114, 1983.
10...... Monitor Section, "From DNA to Hedgehog Dreams", New Scientist, July 28, 1983.
11...... Jim Horne, "Why do we need to sleep?", New Scientist, p.429, 12 Sep., 1981.
12...... Jim Horne, "The Cinema of the Mind", New Scientist, p.627, 2 Sep., 1982.
13...... Morton Schatzman, "Such Stuff as REM Sleep is made of", New Scientist, p.796, 15 Sep., 1983.
14...... "Sleep: the well-hidden secrets of Nature's soft nurse", Economist, p.85, 29 Sep., 1984.
15...... Ramon Greenberg, "Dreams and REM Sleep - An Integrative Approach", p.125 of Ref. 2.
16...... J. S. Antrobus and H. Ehrlichman, "The 'Dream' Report: Attention, Memory, Functional Hemispheric Asymmetry and Memory Organization", p.135 of Ref. 2.
The original of this paper was reported in CANADIANA, (Canada's national bibliography) dated July 1987 under the code C87-6202-6 MRDS Pt.1 612'.821
Previous revision on November 26, 1997.
Latest revision on August 12, 2013.