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Consciousness and Sleep Consciousness is defined as a state of awareness. When conscious we are aware of the sights and sounds of the outside world, of our feelings, our thoughts, and sometimes even our own consciousness. However, there is more than one kind of conscious state; it comes in more than the wide-awake-and-thinking variety. Waking consciousness includes at least three varieties; A- Directed Consciousness: Sometimes our conscious awareness is directed toward a single focus. When we are reading a book, our awareness is absorbed mostly by words and phrases on the page. During such experience, our conscious awareness is focused, ordered, and one-tracked. This is true during any intellectual activity that absorbs awareness, such as during intense emotions or intense sensations. This state is known as directed consciousness. B- Flowing Consciousness: This kind of consciousness is less directed and single-purposed. Here our awareness drifts from one thought to another, from an emotion to an irritating itch, and back to reminiscence. This kind of consciousness was compared to the flow of water in a stream by the psychologist William James. C- Daydreams: Many features of directed and flowing consciousness and dreams are combined in the start of waking consciousness called daydreams. They are periods of thinking and feeling that is not bound by what is logical or likely to happen. Most of us daydream many times each day. Freud believed that daydreams reduced the tension left by our unfulfilled needs and wishes. What we cannot do in reality we accomplish in the fantasy world of daydreams. Divided consciousness: This means being two places (Mentally) at the same time. This phenomena was described by Hilgard (1975) who believes that our conscious awareness becomes ''split'' and we simultaneously perform two activities requiring conscious awareness, e.g. engaging in certain activity while driving, apparently, not aware of the driving and the surrounding environment. The Concept of the Unconscious Mind: The term unconscious is used by psychologists who take a more philosophical approach to understanding people and their problems. It was the concept used first by Freud to describe the part of mind containing the repressed conflicts. Today most scientists agree that it is time to apply scientific thinking to the study of the unconscious. For example, when a person is in a room where more than one person is talking, most of the time we can pay attention to one voice and ''tuned out'' the other voice. This has been called the cocktail party phenomenon because it happens so often in parties. However, what becomes of the other voice- the one we do not listen to? There is evidence that it reaches the brain, even though we are never consciously aware of it. In that sense, the voice is processed unconsciously by the brain. Sleep Sleep is not a single state; instead it is a complex combination of states, some involving conscious awareness. Stages of Sleep: Several states of conscious awareness are part of the sleep process. As we fall a sleep, we pass from waking consciousness into a semi-wakeful state, into four states of progressively deeper sleep (all of which contain little or no conscious awareness), then into dream sleep, which brings a kind of conscious awareness with a reality all its own. These steps in sleep include: A- Hypnagogic state We do not always go directly from wakefulness to sleep. We often, daydream for a while then pass into a ''twilight'' state that is neither daydreaming nor dreaming. This is the hypnagogic state. We begin to lose voluntary control over our body movements; our sensitivity to outside stimuli diminishes; and our thoughts become more fanciful, less bound by reality. For most people it is a highly relaxed, enjoyable state. On some occasion, we suddenly feel as if we are falling and our body experiences a sudden jerk called a myoclonia. B- Sleep Cycle Night sleep is composed of few successive sleep cycles; each cycle lasts around 90 minutes, and includes- four stages of progressively deeper sleep followed by a period of a dreaming or REM (rapid eye movement) sleep lasts 20 minute on average. These levels and types of sleep can be defined on the basis of encephalography (EEG). These types of sleep are classified as follow: a- Non-REM Sleep (NREM) This is considered as the non-dreaming and takes most of the sleeping time and including 4 stages; Stage 1: It is the stage of light sleep, the brain waves-EEG- become less regular and reduced in amplitude. Stage 2: A more deeper sleep, and is characterized by the appearance of spindles-short run of rhythmical responses of 12 to 16 hertz-and K-complex (an occasional sharp rise and fall in the amplitude of the whole EEG). Stage 3 and 4: Characterized by slow waves (1-2 hertz), which are known as delta waves. Generally it is hard to wake the sleeper during these stages. Non-REM sleep is the period of anabolic, building activity of the body. There is increase secretion of many important hormones including growth hormones, cortisol and others. Although this part of sleep is considered as a non-dreaming, the number of dreams that occur is much higher than suspected. The nature of these dreams is quite different from that of REM dreams in that they are more likely to consist of brief, fragmentary impressions that are less emotional and less likely to involve visual images than are REM sleep dreams which looks like watching or involving in play. In NREM sleep, heart and breathing rates decrease markedly, the muscles are relaxed, and the brain's metabolic rate decreases 25% to 30% compared with wakefulness. b- REM-Sleep: The EEG record is that of the waking state, suggesting the presence of conscious awareness In this type of sleep, the characteristic feature is the rapid movement of the eyeballs under the closed eyelids, these very rapid eye movements occur in bursts lasting 10 to 20 seconds. Dreaming is a prominent feature of this period, and is accompanied by physiological and autonomic nervous system changes including the following; Blood flow to the brain increases; the heartbeat becomes irregular; the muscles of the face and fingers twitch; and breathing becomes irregular. Interestingly, voluntary control of the large body muscles is largely lost during REM sleep, perhaps to keep us from acting out our dreams. In addition, there is vaginal lubrication and erection of the clitoris in females and erection of the penis in males which may be accompanied by ejaculation during REM sleep. Succession of sleep stages: After an adult has been asleep for an hour or so, another change occurs. The EEG becomes very active (even more so than when the person is awake), but the person does not wake up. The electrodes placed near the person's eye detect rapid eye movements so pronounced that one can even watch the sleeper's eye move around beneath the closed eyelids. This stage is known as REM sleep; the other four sleep stages are known as non-REM (or NREM) sleep. These various stages of sleep alternate throughout the night. Sleep begins with the NREM stages and has several sleep cycles, each containing some REM and some NREM sleep. The person goes from wakefulness into a deep sleep (stage 4) very rapidly. After about 70 minutes, Stage 3 recurs briefly, immediately followed by the first REM period of night. The deeper stages (3 and 4) occurs during the first part of the night, whereas most REM sleep occurs in the last part. This is the typical pattern: The deeper stages tend to disappear in the second half of the night as REM becomes more prominent. There are usually four or five distinct REM periods over the course of an 8-hour night, with an occasional brief awakening as morning arrives. The pattern of the sleep cycles varies with age. Newborn infants, for instance, spend about half their sleeping in REM sleep. This proportion drops to 20% to 25% of total sleep time by age 5 and remains fairly constant until old age, when it drops to 18% or less. Older people tend to experience less stage 3 and 4 sleep (sometimes these stages disappear) and more frequent and longer nighttime awakening. A natural kind of insomnia seems to set in as people grows older. Dreams Dreams are one of the most fascinating aspects of human consciousness. Since at least the time of the Egyptian pharaohs, people have attempted to decipher the remaining of dreams. When both REM and non-REM dreams are considered. we spend a surprising amount of time in states of consciousness during sleep. In addition to the 2 hours of REM dreaming per night, non- REM dream activity is occurring during half of the other 4 to 6 hours that we sleep each night. Content of Dreams Images and Characters; Most of the conscious experience in dream is visual. Only about one– fourth of dream images include auditory sensations, and about 20 percent include body sensations. About half of the dreams that involve body sensations are sexual- 10 percent of all dreams. Less than 1 percent of dreams include taste or smells. Do you dream in black-andwhite or color? Most people dream in something in between. The visual images in dreams are usually as bright and clear as walking images, but they are drab in color. Dreams are usually include few intense colors and most have blurry backgrounds. Who are the characters in your dreams? The dreamer has an active role in nearly three-fourths of dreams, and your are absent from your own dreams only 10 percent of the time. About half of the other characters are friends, acquaintances, or family members, but the other half are people you do not know or cannot recognize—or are animals 4% of times. The characters in dreams are about an even mixture of men and women. Emotions in dreams-About a thrird of all dreams have some emotional content, about 60% of them have a negative one or mixture of negative and positive emotions. The emotional content of dreams that recur is particularly likely to be negative. Creative and Bizarre Aspects of Dreams- Most of our dreams actually resemble normal, everyday life. About three-fourth of our dreams contain at least one bizarre and unrealistic element. 10% involve mostly nonsensical story lines, and another 10% of dreams are almost completely fantastic and bizarre. Our dreams are twice as twice as likely to be about fictional people and events than real ones, and the settings for our dreams also are more likely to be fictional than real, with sudden and unrealistic changes from one setting to another occurring in one of out of four dreams. Meaning of Dreams: The following features may be considered helpful in understanding the meaning of dreams. a- Day residue and stimulus incorporation: A large part of the content of dreams is directly related to things that are going on in our lives during the day-which Sigmund Freud called day residue. The majority of dreams contain at least one character or event from the preceding day-or, less often, from the preceding week or even earlier in the dreamer's life. The most important characters and events are more likely to reflect day residue than are less central parts. Sometimes the real –world event that is included in the dream is something that is going on while we are asleep. This phenomenon is called stimulus incorporation, In which the stimulus in the real environment is directly incorporated into the dream, but more often it is ''transformed'' somewhat, e.g. including ringing alarm clock or telephone or a sound a flying jet plane that are real events, incorporated in the dream. b- Dream interpretation: According to Freud, there are two levels of the content of dreams: manifest and latent. The events that we experience in dreams are their manifest content, which is the obvious, but superficial, meaning of dreams. While the latent content according to Freud, is the true meaning of dreams that is found in symbols in their manifest content. Freud felt that it was necessary to get beyond the surface and find out what the manifest content of the dream symbolized to discover its true meaning, i.e. its latent content, e.g. to Freud, the snake in the dream refers to the penis. Other Sleep Phenomena These phenomena include; A- Nightmares: These are terrifying kinds of dreams, that occur during REM sleep, and whose content is exceptionally frightening, sad, provoking, or in some other way uncomfortable. They are upsetting enough to wake us up during the dream, so we can vividly remember our nightmares, even though they account for only a small proportion of the dreams most of us have. B- Night terrors: They are a less common but perhaps even more upsetting nocturnal experience. The individual awakens suddenly in a state of panic, sometimes screaming and usually with no clear recollection of an accompanying dream. A sense of calm usually returns within few minutes, but these can be terrifying experiences. Unlike nightmares, they do not occur during REM sleep but occur during the deepest phases of non-REM sleep. Night terrors are most common in preschool-age children, but sometimes adults experience them. C- Sleepwalking: It occurs primarily during the deepest parts of non-REM sleep. Sleepwalkers rise from the bed and carry on complicated activities, such as walking from one room to another, even though they are sound asleep. Sleepwalking is most common in children before the age of puberty but is not particularly unusual in adults. Sleepwalking usually reappears in adults only during periods of stress, but, except for the danger of accidents while wandering around in the dark, it is not an abnormal behavior, D- Sleep talking: It is fairly common phenomenon that can occur during any phase of the sleep cycle. In this, the soundly sleeping person says words, sometimes making fairly coherent statements for a brief period of time. It is most common in young adults but occurs at all ages. Sleep Disorders: 1- Insomnia; It is a disorder in which the person sleeps less than desired. It may be early insomnia in which there is difficulty in falling asleep, and late insomnia in which there is early waking up of sleep. 2- Narcolepsy: It is a rare sleep disorder. The person often falls unexpectedly into a deep slumber in the middle of work or even during conversations with others, often the individual experiences loss of muscle tone and shows a lack of body movement, as if she or he has suddenly fallen into dream sleep, but laboratory studies show that narcoleptic sleep is not REM sleep. Often these sudden bouts of sleep cause serious difficulties with the use of dangerous machines and other job-related activities. 3- Sleep apnea: It is the sudden, temporary interruption of breathing during sleep. This phenomena is common, particularly in older adults who snore. It is caused either by too much relaxation of the muscles of the throat or by a temporary cessation of brain signals for breathing. Circadian Rhythms All people are on a cycle of waking and sleeping that regulates their pattern of sleep, called the circadian rhythm (circa=about; dia=day). Much remain to be learned about circadian rhythms, but the pineal gland seems to be its primary internal or biological'' clock '' and the hormone melatonin a key factor in regulating sleepfulness. The body has many other circadian rhythms, most of which follow the pattern of the sleep-wake cycle. For example, an important hormone of the pituitary that plays a key role in body growth and repair, growth hormone, is secreted mostly during the first 2 hours of sleep. With little secreted during the waking hours of the day. Apparently, this reflects the role that sleep plays in normal growth and the maintenance of health. Body temperature also follow a circadian rhythm that is linked to a sleep cycle. Body temperature fall just as you are beginning to feel sleepy and continues to fall until the middle of the sleep period. Cortisol secretion- which is the adrenal stress hormone, also follows a circadian rhythm that is tied to the sleep period. Its secretion begins to rise shortly after falling asleep and continues to rise through the night. Illumination- The circadian sleep-wake cycle is obviously influenced to some extent by differenced in illumination during the day and night. People throughout the world generally are awake when it is light and sleep when it is dark, although many cultures take –siestas- during the days and other cultures have long periods without –days and nightsThe obvious and most dramatic way that most of us will become aware of circadian rhythms is by disrupting them with long airline flights. Not all of the natural rhythms of life are daily rhythms. As in menstrual cycle that follow a 28-day rhythm. Also there is an annual cycle in mood changes. Altered States of Consciousness There are many kinds of altered states of consciousness and they differ from one another in important ways, yet these altered states –whether they occur during meditation, during drug use, during an unusually intense sexual orgasm, or during a moment of religious conversion— have been described as having a number of characteristics in common: 1- Distortions of perception: In altered states of consciousness, distortions often occur in what is seen, heard, and felt. Time passes differently, and the body may seem distorted-indeed, the body may even seem to have been left behind and is being observed from the outside. 2- Intense positive emotions: People who have experienced altered states of consciousness frequently describe them as joyful, ecstatic, loving, and tranquil experience. 3- Sense of unity: Individuals often experience a sense of being unified with nature, blended with the universe, or ''one'' with spiritual force. 4- Illogical: Many of the experiences and ''revelations of the altered states of consciousness do not make sense by the standards of everyday logic. For example, the experience that ''I exist as a separate person, yet I am one with the universe'' is typical of altered states. 5- Indescribable: Individuals who have experienced altered states of consciousness usually feel that words cannot adequately express the nature of their experience. Our language may not have words for many of the qualities of the experience, but the difficulty also may come from trying to describe illogical experiences with language. 6- Transcendent: The altered states are experienced as transcending—going beyond— what is normally experienced. In particular, the individual may experience a new perspective that goes beyond ordinary conceptions of space and time limitations. 7- Self-evident reality: New revelations and insights are experienced that concern ''ultimate reality'' and are felt to be ''real'' in a way that requires no proof. The insight is intuitively and immediately understood as the truth; it requires no explanation or justification. A-Meditation: It is one method of searching for an alternative to waking consciousness. It is more popular in Asians cultures commonly as a form of religious rituals as in Zen Buddhism. Meditation involves several methods of focusing concentration away from thoughts and feelings and generating a sense of relaxation. There are many varieties of medication, some very difficult to master and others much simpler. In its simplest form, meditation involves assuming a relaxed sitting or lying position and breathing deeply, slowly, and rhythmically. Attention is directed only at the breathing movements of the diaphragm, and all other thoughts and feelings are gently blocked from consciousness. In some forms of meditation, the individual also repeats a sound or word silently to himself or herself. These words often have special religious meaning (mantras), but researchers have found that any pleasant sound or words (such as calm or one) has the same effect of further focusing attention away from thoughts and feelings. Once mastered, the practice of meditation can produce what many describe as a desirable altered state of consciousness. If nothing else, meditation generally produces a relaxed state. Some experienced meditators also report achieving an altered state of consciousness—the so-called transcendental state—that is very different from normal consciousness. Because the state of meditation often involves a reduction in sympathetic autonomic arousal, meditation has been prescribed for more than 20 years as a natural remedy for stress-related medical problems ranging from high blood pressure to insomnia. As a result, thousands of people practice meditation; however, this is still controversial. B-Hypnosis: It is an altered state of consciousness in which the individual is highly relaxed and susceptible to suggestions. The person becoming hypnotized focuses his or her attention firmly on the hypnotist's voice and is talked and lulled into an altered state of consciousness. This hypnotic state differs from individual to individual but typically has the following characteristics: 1- Relaxation: A sense of deep relaxation and peacefulness, often accompanied by changes in the way the body feels, such as floating or sinking. 2- Hypnotic hallucinations: When told to do so, the person may see, feel, or hear things in altered ways or may even experience things that are not there, such as smelling a flower that does not exist. 3- Hypnotic analgesia: When told to do so, the person may lose the sense of touch or pain in some region of the body. This is one of the best validated aspects of hypnosis and has led to the use of hypnosis in surgery, dentistry, and childbirth. 4- Hypnotic age regression: The person can sometimes be made to feel that he or she is back in time to an earlier stage of life, but most experts do not believe that hypnosis improves the recall of childhood events. 5- Hypnotic control: The actions of hypnotizes individuals sometimes seem as if they are out of their own control. When told that her arm can float, a hypnotized person's arm may seem to float up as if it were lifted by invisible balloons rather than by her own muscles. Mesmer and Mesmerism: Mesmer was a practicing physician in Paris in the late 1700s. He treated patients with medical or psychological problems in what he called magnetic séances. Mesmer believed that all living bodies were filled with magnetic energy and that the disease resulted when these magnetic forces were out of balance. His treatment, therefore, consisted of passing his hands, which he believed had become magnetized, over the afflicted part of the patient's body and having the patient touch metal rods that protruded from a large tub. The tub was filled with water, chemicals, ground glass, and iron filing—a mixture that the Mesmer thought created magnetism. What Mesmer actually created, was an atmosphere that induced a mysterious and powerful hypnotic trance. He entered the darkened and silent room wearing flowing lilac-colored robes. He lulled his patients into deep state of relaxation and made them believe deeply in his healing powers; that is, he hypnotized them. He told them that their problems would go away, and some of them did. The process of putting people into hypnotic trances came to be known for many years as mesmerism. Only much later was it referred to as hypnosis. There are two views on the basis of hypnosis: one that it is not as a trance but as a highly relaxed state in which the person's conscious awareness is highly focused, the person's imagination is highly intensified, and the person is highly susceptible to the instructions of the hypnotist, while the other view sees hypnosis as based on divided consciousness, e.g. individuals can experience a loss of pain through hypnosis because that part of consciousness can be separated from waking consciousness. In recent years hypnosis has gained limited acceptance by the medical and dental professions for the relief of pain through hypnotic analgesia, e.g. patients who cannot use analgesic medications for a variety of reasons have been able to have extensive operations or undergo childbirth under hypnosis with little or no pain. C-Depersonalization: It is a spontaneous experience, refers to the perceptual experience of one's body becoming ''distorted'' or ''unreal'' in some way or the sense of strange distortions in one's surroundings (this referred to as –derealization). The person feels as if he is not himself or he is changed in a way he cannot understands. It may occur in normal people under stressor exhaustion or in drug abuse or in psychiatric conditions as anxiety. D-Near-Death Experience: This phenomenon is based on the information available on the experience of nearly dying, and from patients who have had clinical death following sudden cardiac arrest after which life is restored, spontaneously or after treatment. Those individuals typically reported the following sequence of events First, their heads were filled with a pleasant, sometimes musical ringing or buzzing sound. Next, they sensed their minds or ''spirits'' separated from their bodies. Sometimes they were able to watch the physician trying to revive them, but more often they felt that they were being transported quickly away from their bodies. This was experienced as moving through what felt like a long tunnel. At first, the experience of dying was an unpleasant one as the individual fearfully fought death. But a sense of peace soon settled over them. Many individuals reported seeing the spirits of dead loved ones while passing through the tunnel and, in time, the tunnel brightened and shining, God-like spirit of love was felt at the end of the tunnel. But at this point all of the interviewed individuals returned to normal ''living'' as their hearts were restarted. Lately, a group of physicians in England carried out an extended clinical research on such patients in a hospital, In Portsmouth. Result not published yet. Neurological Basis of Consciousness: The part of the nervous system responsible for consciousness, arousal and sleep is the reticular formation. This neuronal system is composed of a network of neurons and pathways that are extended from the spinal cord up to the thalamus. It contains the vital centers of CVS and respiration, it also has the function of regulating muscular contractions through the Gamma-loop system. In the brain stem the reticular formation form the reticular activating system-RAS, which receives sensation from the spinal cords and by collaterals from all the sense organs. These sensations are projected from the thalamus to the cerebral cortex which result in the mechanism of consciousness and arousal which can be investigated by psycho-physiological tests particularly electroencephalography- EEG.