History

Dreaming can be described as a phenomenon that dates back in time to when human beings first evolved.  There are multiple definitions for dreaming as understood and believed from different cultures across the world.

Ancient Egyptians believed dreams were messages from God and that dreams were a form of predicting the future.  They classified dreams into three categories the pious, revelatory, and informational.  Pious dreams involved messages from God asking for devotees to perform a particular act of devotion.  Revelatory dreams carried a prediction for the future and informational dreams carried some important and significant information. 

According to Greek mythology Hypnos was worshipped as the God of sleep and his son Morpheus was the God of dreams.  In the year 350 B.C. Aristotle, the famous Greek philosopher for the first time defined dreams to be originating from within one Self.  With this people started to consider and understand the metaphysical nature of dreams.  Taking this theory forward, the father of modern medicine, Hippocrates started believing dreams to be a significant part of his diagnostic technique and claimed that it helped him analyze his patient’s better.

Several thousand years ago, holy Hindu scriptures called the Upanishads portrayed dreaming as a higher state of consciousness in comparison to the waking state.  The Upanishads described the cycle of consciousness to work in seven steps or stages; the waking/conscious stage, transition, dreaming/unconscious state, transition again, deep sleep/subconscious stage, samadhi/state of true yoga, and turiya/absolute consciousness.  The second stage of dreaming is considered to be higher and superior to the first stage of waking or conscious stage because the soul is freed from the physical body and is partially awake in the astral plane.

Ancient Chinese believed that the dreamer’s soul is responsible for the dreams and while dreaming the soul leaves the physical body to visit the land of the dead.  Dream temples were built and Chinese leaders were advised to visit these temples for guidance and wisdom to carry out their mission.

Throughout the West people believed that dreams were a direct communication from God and Christianity too referred to dreaming as a form of communicating with the divine.  The Bible has references to divine dreams and how people have interpreted these dreams.

Thousands of years later, the father of psychoanalysis, Sigmund Freud defined dreaming as a psychological process that is based on personal experiences and unfulfilled desires that have a deep and insightful psychoanalytical meaning.  In the year 1900, Freud released his book, The Interpretation of Dreams, which describes dream analysis as “a royal road to the understanding of unconscious mental processes.”  According to Freud, dreams were a means by which the unconscious mind was trying to fulfill the unfulfilled desires of the conscious mind.  Freud stated that there are no chance happenings and in order to inhabit the human society we suppress and repress our emotions and impulses, and once repressed these manifest in our dreams and therefore dreams are a natural form of releasing these unexpressed emotions and urges.

Freud’s contemporary Carl Jung did not agree with him and believed that dreams are:

A direct reflection of the day-to-day activities and dreams bring about a psychic balance in a person’s life.  For example, if you are feeling sad at a conscious level then you might have a happy dream and if you are thrilled about something you might dream about something depressing.  Thus dreams are a way of compensating at the subconscious level for what is happening at a conscious level.

Dreams are also a form of expression or reaction to a particular experience or episode.  For example, a rape victim might dream of this negative incident soon after the incident and the dream will be very close to what transpired during the real-life experience, and eventually these nightmares might decrease in frequency but appear in a different form.

Dreams can be an indication of what could happen in the future; again dreams are symbolic and cannot be interpreted literally.

Dreams could be telepathic in nature and is way of communicating to another person or another part of a person’s psyche without involving the senses.

Dreams can also be mimetic or take the form of a premonition of conditions that are occurring in the physical body of a person who is unaware of these conditions that are manifesting in a person.

Another famous psychologist Alfred Adler described dreaming as an indication of our true feelings, thoughts, emotions, and actions.  Adler believed that dreams were a means of overcoming a dreamer’s weaknesses and shortcomings in the conscious world.  According Adler, dreams help the dreamer to deal with his fears by acting as an outlet to do and say things that he wouldn’t have been comfortable expressing at a conscious level.  For example, an abused wife might actually shout back at her husband in her dream, thereby satisfying the need to express her anger that is felt during the actual experience.

As per the Gestalt therapy founded by Fredrick and Laura Perls, dreams contain the neglected or disowned and rejected parts of the Self.  Perls stated that dreams were an expression of oneself and dreams were an active means of filling the emotional gaps in a person in an attempt to become a unified whole.

Then came the neurophysiological school of thought that determined the four stages of sleep, and they are slow, delta, spindle, and REM.  It was further concluded that dreams occur during the REM or last stage of sleep mostly due to a chemical transaction that takes place during the REM stage of sleep.

To conclude dreaming is more of a creation than a medium of communication and if a dream can be interpreted don’t hesitate to do so or just leave it alone.  Dreaming is a natural phenomenon that occurs from time to time, unless it is disturbing in nature and interferes with your sleep cycle you might want to consult an expert and seek advice.

PHYSIOLOGY

Dream Stages

The various stages of sleep were described for the first time in the 1930s by Loomis, and later in the 1950s by Aserinsky and Leitman, identified Rapid Eye Movement (REM) sleep. 

NREM and REM

Sleep can be divided into two main categories:

Non-rapid Eye Movement (NREM) sleep
Rapid Eye Movement (REM) sleep

Sleep begins with NREM or SWS (slow wave sleep) and progresses to REM sleep. NREM and REM occur in alternating cycles, the duration of each cycle spanning about 90-100 minutes, with a total of 4 to 6 cycles. There are three major slow oscillatory rhythms in NREM sleep and one fast oscillating rhythm during waking and REM.

NREM (Non-rapid Eye Movement)

Stage 1 occurs in the beginning of sleep with slow eye movements. During this stage the alpha waves disappear and theta waves appear.  During the period of transition into Stage 1 NREM, people experience hypnic jerks.  People woken up at this stage believe that they were fully awake. 

Stage 2 is an unconscious stage but the sleeper is easily awakened during this stage.  No eye movements occur during this stage therefore dreaming is of rare occurrence during this stage of sleep. EEG recordings show characteristic sleep spindles and K-complexes during this stage.  This rhythm is generated by the reticular nucleus of the thalamus.  The spindle stage blocks transmission of the outside environment with the cortex.  Though neither the cortex nor the thalamus require the other for function during these stages they do interact.

Stage 3 is the transition between stage 2 and stage 4 where delta waves associated with deep sleep start occurring.

Stage 4 is the slow wave sleep stage, also referred to as SWS.  This happens to be the deepest stage of sleep where there is continuation of delta waves.  Dreaming is most common during this stage when compared to the other stages of NREM sleep but not as common as in REM sleep.  The contents of SWS dreams tend to be disconnected, less clear, and less memorable when compared to the content of dreams that occur during REM sleep.  This is also the stage in which parasomnias most commonly occur.

REM (Rapid Eye Movement)

This is a normal stage of sleep characterized by rapid movements of the eyes.  REM sleep can be further classified into two main categories; tonic and phasic, which was first identified and defined by Kleitman and Aserinsky in the early 1950s.

REM sleep in a normal healthy young adult takes up about 20-25% of total sleep, which translates to about 90 to 120 minutes of a night’s sleep.  During the course of a normal night of sleep, humans usually experience about 4 to 5 periods of REM sleep; they are relatively short at the beginning of the night and longer towards the end.  Most people tend to wake, or experience a period of very light sleep, for a short time immediately after a bout of REM.  The relative amount of REM sleep varies considerably with age.  A newborn baby spends more than 80% of total sleep time in REM.

During REM, the activity of the brain’s neurons is similar to that during waking hours, for this particular reason, the phenomenon is called paradoxical sleep, which means that there are no dominating brain waves during REM sleep.

REM sleep is physiologically different from the other phases of sleep, which are collectively called non-REM sleep.  Vividly recalled dreams mostly occur during REM sleep.  These dreams are also those dreams that most likely to be remembered upon waking up.  It is felt that that the length of the REM sleep cycle might be correlated to the brain size. 

Hobson’s reciprocal-interaction model gives a biological explanation to the chemical transaction that take place during REM. REM is generated in the pontine reticular formation and REM is turned on by cholinergic neurotransmitters. Serotonergic and noradrenergic neurotransmitters inhibit the cholinergic neurotransmitters turning REM off. The function of REM has not been definitely determined. One theory is an evolutionary, adaptive function. Another function may be a restorative process for some types of memory during REM sleep, but it has been firmly established that REM is when dreaming occurs in the sleep cycle.

Once it was established that dreams are generated during REM, it became very important to find out the reasons for dreaming and to get into the details of the functions of dreaming.  There are two fundamental theories that describe the function of dreaming.  One is an adaptive evolutionary function and another is restorative memory function.

While psychoanalysts argued that we dream to forget and not include certain traumatic memories into our dreams, neurobiologists insisted that dreaming is a phenomenon during which suppressed and repressed memories are brought to the surface. Neurobiologists concluded that disturbances in REM sleep end up in nightmares and horrifying dreams; which could also result in narcolepsy because of an increase in REM latency and a decrease in REM time.  Hence they felt that people who have gone through violent experiences try not to allow these experiences to be part of their long term memory and that the entire function of dreaming was a step towards memory consolidation.

Current research suggests a more involved chemical exchange in the reciprocal-interaction model than was once thought. Though dreams may not have meaning as Freud suggested, dreams still seem to reflect an individual’s stored memory and emotion brought about by chemical exchanges in the brain and brainstem.

Features of Dreams

What are the predominant features of dreaming and how do they occur?  To begin with there are four features of dreams, and they are bizarreness, motor hallucination, emotion, and memory deficit. 

Bizarreness is described as being the incongruence of plot, the instability of time, people, and places. Bizarreness consists of various aspects of activation and deactivation within the brain. The deactivation of the fusiform gyrus, is responsible for face recognition. The deactivation of the parietal operculum is responsible for special imagery. The dorsolateral prefrontal areas and precuneus both associated with the encoding and retrieving of episodic memory. The prefrontal area and the parietal lobules are associated with working memory.

Motor hallucinations, visual and motor, are active behaviors such as running, flying etc,. Emotions are perceived as an increased intensified fear, anxiety and anger. Memory deficits make recall during consciousness difficult.  The causes of these features are the activation or deactivation of certain structures within the brain and brainstem. Motor hallucinations may be caused by the activation of the basal ganglia, visual cortex, lateral geniculation nucleus motor cortex and auditory cortex.

Emotions are caused by the activation of medial limbic and paralimbic structures, which shape the plot of the dreams through the emotions and not vise versa.

Memory deficits are thought to be the absence of noradrenaline and serotonin, which are crucial to learning and memory.

Sleep Timing

Sleep timing is controlled by three main factors and they are the circardian clock, homeostasis and in humans by willed behavior.

The circadian clock is an inner time-keeping, temperature-fluctuating, enzyme-controlling device, which works in tandem with adenosine, a neurotransmitter which inhibits many of the bodily processes that are associated with wakefulness.

Adenosine is generated during the day and increased levels of adenosine leads to sleepiness. In diurnal animals, sleepiness occurs as the circadian element causes the release of the hormone melatonin and a gradual decrease in core body temperature. The timing is affected by one's chronotype. It is the circadian rhythm which determines the ideal timing of a correctly structured and restorative sleep episode.

Homeostatic sleep propensity is the need for sleep as a function.  The amount of time elapsed since the last adequate sleep episode is an important factor and must be balanced against the circadian element for satisfactory sleep. This along with corresponding messages from the circadian clock, informs the body that it needs to sleep. Sleep offset, awakening, is primarily determined by circadian rhythm. A normal person who normally wakes up at an early hour will not be able to sleep much later than a person who wakes up at his normal waking time, even though he or she is moderately sleep deprived.

The association of circadian rhythms and sleep is clear and further research and development in genetics and molecular biology will add more clarity and scientific evidence to functions of the circadian clock and how behavioral patterns will evolve and adjust to the light and dark cycles. 

In addition to the circadian component, there is a fundamental regulatory process involved in programming sleep. Sleep deprivation and the need for sleep are almost directly proportional to each other, for instance, it is quite evident and conclusive that the more a person is deprived of sleep the more he or she needs to sleep. This need to sleep is the definition of the hemostatic component of sleep.  The precise mechanism that generates this pressure and makes us feel the need to sleep remains a mystery. However we have established that the action of nerve-signaling molecules called neurotransmitters and nerve cells (neurons) are located in the brainstem and at the base of the brain.  These neurotransmitters and nerve cells determine whether we are asleep or awake.

Additionally, there is recent evidence that the molecule adenosine (composed of the base adenine linked to the five-carbon sugar ribose) is an important factor that is responsible for sleepiness and it appears to “keep track” of lost sleep and may induce sleep. Interestingly, caffeine binds to and blocks the same cell receptors that recognize adenosine. This suggests that caffeine disrupts sleep by binding to adenosine receptors and preventing adenosine from delivering its fatigue signal. The homeostatic regulation of sleep helps reinforce the circadian cycle. We usually sleep once daily because the homeostatic pressure to sleep is hard to resist after about 16 hours, and then while we sleep, our closed eyes block the light signals to the biological clock.

The biological clock that times and controls a person’s sleep/wake cycle will attempt to function according to a normal day/night schedule even when that person tries to change it. Those who work night shifts naturally feel sleepy when nighttime comes. A similar feeling that occurs during travel is known as jet lag.  During jet lag there is a conflict created by trying to be active during the brain’s biological nighttime, which leads to a decrease in cognitive and motor skills. The biological clock can be reset, but only by appropriately timed cues and even then, by one to two hours per day at best.  Problems resulting from a mismatch of this type may be reduced by following some basic rules like sleeping in a dark, quiet room, and getting exposure to bright light at the right time, and altering eating and exercise patterns. Because humans function best when they sleep at night and act in the daytime, the task for a person who must be active at night is to retrain the biological clock (by light cues).

An internal biological clock regulates the timing for sleep in humans. The activity of this clock makes us sleepy at night and helps us stay awake during the day. Our clock cycles for a 24-hour period and is called a circadian clock (from the Latin roots circa = about and diem = day). In humans, this clock is located in the suprachiasmatic nucleus (SCN) of the hypothalamus in the brain. The SCN is actually a very small structure consisting of a pair of pinhead-size regions, each containing only about 10,000 neurons out of the brain’s estimated 100 billion neurons.

Biological clocks are genetically programmed-physiological systems that allow organisms to live in harmony with natural rhythms, such as day/night cycles and the changing of seasons. The most important function of a biological clock is to regulate overt biological rhythms like the sleep/wake cycle. The biological clock is also involved in controlling seasonal reproductive cycles in some animals through its ability to track information about the changing lengths of daylight and darkness during a year.

Biological rhythms are of two general types, exogenous rhythms and endogenous rhythms. Exogenous rhythms are directly produced by an external influence, such as an environmental cue. The organism itself does not generate exogenous rhythms internally, and if the environmental cues are removed, this rhythm ceases. Endogenous rhythms, however, are driven by an internal, self-sustaining biological clock rather than by anything external to the organism. Biological rhythms, such as oscillations in core body temperature, are endogenous. They are maintained even if environmental cues are removed.

In general, the human circadian clock appears to be better equipped to adjust to a longer day than a shorter day. For example, it is easier for most people to adjust to the end of daylight savings time in the fall when we have one 25-hour day than to the start of daylight savings time in the spring, when we have a 23-hour day. Similarly, traveling from the West Coast of the United States to the East Coast produces a loss of three hours—a 21-hour day. Thus, travelers may find it difficult to sleep because of the three-hour difference between external cues and their internal clock. Likewise, travelers may find it difficult to awaken in the morning. We may try to go to sleep and wake up at our usual local times of, say, 11 p.m. and 7 a.m., but to our brain’s biological clock, the times are 8 p.m. and 4 a.m. This particular lag, which people experience when they travel to and from different time zones, is referred to as Jet Lag.

Jet lag is a direct consequence caused due to the inability of our circadian clock to make a quick adjustment to the changes in light cues that come from a rapid change in time zone. After such travel, the body is in conflict. The biological clock carries the rhythm entrained by the original time zone, even though the clock is out of step with the cues in the new time zone. This conflict between external and internal clocks and signals is called desynchronization and it affects more than just the sleep/wake cycle. All the rhythms are out of sync, and they take a number of days to re-entrain to the new time zone.

When daily sleep time is less than an individual needs, a “sleep debt” develops. Even relatively modest daily reductions in sleep time (for example, one hour) can accumulate across days to cause a sleep debt. If the debt becomes too great, it can lead to problem sleepiness. Although the individual may not realize his or her sleepiness, sleep debt can have powerful effects on daytime performance, thinking, and mood.

The Right Amount

Sleep is a natural and normal state of bodily rest observed throughout the animal kingdom. It is a phenonemon that occurs in mammals and birds and also in many other species from the animal kingdom like many reptiles, amphibians, and aquatic creatures . In humans, other mammals, and a substantial majority of other animals which have been studied — such as fish, birds, ants, and fruit-flies, regular sleep is essential for survival. However, its purpose is only partly clear and is the subject of intense research.

What could be the right amount of sleep for a person at 40 years of age might not necessarily be the right amount of sleep for a two-month old baby.  The optimum amount of sleep is of lesser consequence if the timing of sleep is not right.  Hence the right amount of sleep should also be viewed in context to an individuals’ circadian rhythm.  It is therefore important to get the right amount of sleep during the right time.  The ideal conditions for the right amount sleep is when optimum concentration of hormone melatonin occurs and at minimum body temperature.

The National Sleep Foundation in the United States maintains that eight to nine hours of sleep for adult humans is optimal and that sufficient sleep benefits alertness, memory, problem solving skills, and overall health and at the same time reduces the risk of accidents.  A widely publicized 2003 study  performed at the University of Pennsylvania School of Medicine demonstrated that cognitive performance declines with fewer than eight hours of sleep.

However, the University of California, San Diego Psychiatry study of more than one million adults found that people who live the longest self-report sleeping for six to seven hours each night. Another study of sleep duration and mortality risk in women showed similar results. Other studies show that "sleeping more than 7 to 8 hours per day has been consistently associated with increased mortality", though this study suggests the cause is probably other factors such as depression and socio-economic status which would correlate statistically. It has been suggested that the correlation between lower sleep hours and reduced morbidity only occurs with those who wake after less sleep naturally, rather than those who use an alarm.

Causal links are currently speculative, the available data may only reflect comorbid depression, socioeconomic status, or even alcohol use.  These studies cannot be used to determine optimal sleep habits, they only establish a correlation — and empirically observed correlation is a necessity but not sufficient condition or grounds for causality.  A need for nine or ten hours of sleep a day, or only five to six, may or may not have the same cause as the shortened life span. In other words, long or short sleep duration by itself has not been shown to be a cause of early death.

Researchers from the University of Warwick and University College of London have found that lack of sleep can more than double the risk of death from cardiovascular disease, at the same time too much sleep can also double the risk of death. Professor Francesco Cappuccio said: “Short sleep has been projected to be a risk factor for weight gain, hypertension and Type 2 diabetes sometimes leading to mortality.  Therefore, while short sleep-mortality association has been established there are no potential mechanisms by which long sleep could be associated with increased mortality, or they haven’t yet been investigated. Some causes for this include depression, low socioeconomic status and cancer-related fatigue. In terms of prevention, our findings indicate that consistently sleeping around 7 hours per night is optimal for health and a sustained reduction may predispose a person to ill-health.”

Children need a greater amount of sleep per day when compared to adults in order to develop and function properly.  Newborns require up to 18 hours of sleep, with a declining rate as a child ages.  A newborn baby spends almost half of its sleep time in REM-sleep. By the age of five or so, only a bit over two hours are spent in REM.

As described earliery, if a person doesn’t get the right amount of sleep everyday consistently over a period of time, this sleep decifit will accumulate and this build up will translate to sleep debt.  Hence sleep debt is the effect of not getting enough rest and sleep; a large debt causes mental, emotional and physical fatigue. Scientists do not agree on how much sleep debt it is possible to accumulate, whether it is accumulated aginst an individual's average sleep or some other benchmark, nor on whether the prevalence of sleep debt among adults has changed appreciably in the industrialized world in recent decades. It is also likely that children are sleeping less than previously.

Even relatively modest daily reductions in sleep time (for example, one hour) can accumulate across days to cause a sleep debt. If the debt becomes too great, it can lead to problem sleepiness. Although the individual may not realize his or her sleepiness, the sleep debt can have powerful effects on daytime performance, thinking, and mood thereby affecting his or her health and also the quality of life.

Older people don’t need less sleep, but they oftenget less sleep. That’s because the ability to sleep for long periods of time and to get into the deep, restful stages of sleep decreases with age. Many older people have more fragile sleep and are more easily disturbed by light, noise, and pain than when younger. They are also more likely to have medical conditions that contribute to sleep problems.

Excessive daytime sleeping

Excessive daytime sleepiness can be associated with a sleep disorder or other medical conditions. Sleep disorders, including sleep apnea (that is, absence of breathing during sleep), insomnia, and narcolepsy, and may require behavioral, pharmacological, or even surgical interventions to relieve the symptoms. Extra sleep may not eliminate daytime sleepiness caused by these disorders.

Sleep deprivation and wakefulness

About 30 to 40 percent of adults indicate some degree of sleep loss within any given year, and about 10 to 15 percent indicate that their sleep loss is chronic or severe. In addition, millions of Americans experience problems sleeping because of undiagnosed sleep disorders or sleep deprivation.

Adolescents and shift workers are at very high risk of problem sleepiness due to sleep deprivation and the desynchronized timing of sleep and wakefulness, respectively. Sleep and wakefulness are linked in part to the activity of the circadian clock. Recent studies show that individual preferences for morning and evening activity may have a biological basis. In addition, studies show that adolescents experience a delay in the circadian timing system that results in a tendency for them to stay up later and sleep in later.

Loss of sleep creates an overwhelming and uncontrollable need to sleep and affects all physiological functions. Sleep loss causes problems with memory and attention, complex thought, motor responses to stimuli, performance in school or on the job, and controlling emotions. Sleep loss may also alter thermoregulation and increase the risk for various physical and mental disorders. Many adolescents are chronically sleep-deprived and hence at high risk of drowsy-driving crashes.

Sleep loss affects personal safety on the road. The National Highway Traffic Safety Administration has estimated that approximately 100,000 motor vehicle crashes each year result from a driver’s drowsiness or fatigue while at the wheel. Driving at night or in the early to mid afternoon increases the risk of a crash because those are times that our biological clocks make us sleepy. Drowsy driving impairs a driver’s reaction time, vigilance, and ability to make sound judgments. Many adolescents are chronically sleep-deprived and hence at high risk of drowsy-driving crashes. In one large study of fall-asleep crashes, over 50 percent occurred with drivers who are 25 years old or younger.

Functions of Sleep

Restoration

The multiple theories proposed to explain the function sof sleep reflect the as-yet incomplete understanding of the subject.

It is likely that sleeping as a function evolved to fulfill some primeval function, but has taken over multiple functions over time as organisms have evolved. An analogy would be that to the larynx, which performs multiple functions, such as controlling the passage of food and air, phonation for communicating and social purposes, etc. These are all functions of the larynx, but just one of them likely represents the original function. Some of the many proposed functions of sleep are as follows:

Wound healing has been shown to be affected by sleep. A study conducted by Gumustekin et al. in 2004 shows sleep deprivation hindering the healing of burns on rats.

A study by Bonnet and Arand in 2003 indicates that sleep affects metabolism. Comparing normal human sleepers and sleepers with sleep state misperception insomnia, where patients complain of poor sleep but have normal sleep by electroencephalographic (EEG) criteria, the researchers found significantly greater metabolism values for the normal sleepers.

It has yet to be clearly proven that sleep duration affects somatic growth. One study by Jenni et al in 2007 recorded growth, height and weight, as correlated to parent-reported time-in-bed in 305 children over a period of nine years (age 1-10). It was found that "the variation of sleep duration among children does not seem to have an effect on growth". It has been shown that sleep, more specifically slow-wave sleep (SWS), does affect growth hormone levels in adult men. During eight hours sleep, Van Cauter, Leproult, and Plat found that the men with a high percentage of SWS (average 24%) also had high growth hormone secretion, while subjects with a low percentage of SWS (average 9%) had low growth hormone secretion.

There are multiple arguments supporting the restorative function of sleep. We feel rested after sleeping, and it is natural to assume that this is the basic purpose of sleep. Overall metabolic rate goes down during sleep and certain anabolic hormones such as growth hormones as mentioned above are secreted preferentially during sleep. Sleep among species is, in general, inversely related to the animal size and basal metabolic rate. Rats with a very high basal metabolic rate sleep for up to 14 hours a day whereas elephants and giraffes with lower BMRs sleep only 3-4 hours per day.

Energy conservation could as well have been accomplished by resting quiescent without shutting off the organism from the environment, potentially a dangerous situation. A sedentary non-sleeping animal is more likely to survive predators, while still preserving energy. Sleep therefore does something else other than conserving energy. Most interestingly, hibernating animals that wake up from hibernation go into rebound sleep because of lack of sleep during the hibernation period. They are definitely well rested and are conserving energy during hibernation, but need sleep for something else. Rats kept awake indefinitely develop skin lesions, hyperphagia, loss of body mass, hypthermia and eventually septicemia and death.

Anabolic/catabolic

Non-REM sleep may be an anabolic state marked by physiological processes of growth and rejuvenation of the organism's immune, nervous, muscular, and skeletal systems (with some exceptions). Wakefulness may perhaps be viewed as a cyclical, temporary, hyperactive catabolic state state during which the organism acquires nourishment and reproduces.

Ontogenesis

According to the ontogenetic hypothesis of REM sleep, the activity occurring during neonatal REM sleep (or active sleep) seems to be particularly important to the developing organism (Marks et al., 1995). Studies investigating the effects of deprivation of active sleep have shown that deprivation early in life can result in behavioral problems, permanent sleep disruption, decreased brain mass (Mirmiran et al. 1983), and an abnormal amount of neuronal cell death (Morrissey, Duntley & Anch, 2004).

REM sleep appears to be important for development of the brain. REM sleep occupies majority of time of sleep of infants, which spend most of their time sleeping. Among different species, the more immature the baby is born, the more time it spends in REM sleep. Proponents also suggest that REM-induced muscle inhibition in the presence of brain activation exists to allow brain development by activating the synapses yet without any motor consequences which may get the infant into trouble. Additionally, REM deprivation results in developmental abnormalities later in life.   However, this does not explain why older adults still need REM sleep. Aquatic mammal infants do not have REM sleep in infancy REM sleep in those animals increases as they age.

Animal studies have demonstrated that sleep is essential for survival. Consider studies that have been performed with laboratory rats. While these animals will normally live for two to three years, rats deprived of REM sleep survive an average of only five months. Rats deprived of all sleep survive only about three weeks.  In humans, extreme sleep deprivation can cause an apparent state of paranoia and hallucinations in otherwise healthy individuals. However, despite identifying several physiological changes that occur in the brain and body during sleep, scientists still do not fully understand the functions of sleep. Many hypotheses have been advanced to explain the role of this necessary and natural behavior.  The following examples highlight several of these theories:

The theory of restoration recognizes the need for an organism to replenish its energy stores and generally repair itself after a period of energy consumption and breakdown (wakefulness). The brain remains active during sleep, and the low metabolic rate characteristic of sleep is thought to be conducive to biosynthetic reactions. There is little, if any, evidence that more repairs occur during sleep than during rest or relaxed wakefulness. In fact, whole-body protein synthesis decreases during sleep, which is consistent with sleep being a period of overnight fasting.

Sleep is one of nature’s greatest inventions and blessings of life. It is a periodic rest of the body, which is absolutely essential for its efficient functioning. It has been called "most cheering restorative of tired bodies."  Sleep is an indispensable condition and is absolutely necessary for the recuperation of energy. We go to bed fatigued and get up refreshed. Sleep repairs the wear and tear of the body and mind incurred during waking hours. Nothing is so restorative to the nerves as sound and uninterrupted sleep. Sleep is thus a vital element throughout the life of all mammals and most other animals and birds in the animal kingdom.  It is a basic need in man’s mental as well as physical life.

During sleep most of the functions of the body are carried on at the lowest level possible in health. Heat production is from 10 to 15 per cent below the basal level. The mechanism regulating the body temperature is less sensitive than in the waking state and are depressed by 0.5 to 1.0 degree F. The rate of the heart is reduced by 10 to 30 beats per minute and a decline in blood pressure of about 20 mm occurs in quiet restful sleep. The urine volume is considerably reduced, but its concentration in solids is increased. The tone of all the skeletal muscles is lessened. The eyes are usually rolled upward and the pupils constricted. Loss of sleep exerts serious detrimental effects upon the nervous system.

Long periods of wakefulness may cause profound psychological changes such as loss of memory, irritability, hallucination and even schizophrenic manifestations. During the last World War, prisoners in Nazi concentration camps who were kept awake for days by strong lights and blaring wireless sets, collapsed.

The Memory Process

Scientists have shown numerous ways in which sleep is related to memory. In a study conducted by Turner, Drummond, Salamat, and Brown working memory was shown to be affected by sleep deprivation. Working memory is important because it keeps information active for further processing and supports higher-level cognitive functions such as decision making, reasoning, and episodic memory. Turner et al. allowed 18 women and 22 men to sleep only 26 minutes per night over a 4-day period. Subjects were given initial cognitive tests while well rested and then tested again twice a day during the 4 days of sleep deprivation. On the final test the average working memory span of the sleep deprived group had dropped by 38% in comparison to the control group.

Memory also seems to be affected differently by certain stages of sleep such as REM and slow-wave sleep (SWS). In one study cited in Born, Rasch, and Gais multiple groups of human subjects were used; wake control groups and sleep test groups. Sleep and wake groups were taught a task and then tested on it both on early and late nights, with the order of nights balanced across participants.

When the subjects' brains were scanned during sleep, hypnograms revealed that SWS was the dominant sleep stage during the early night representing around 23% on average for sleep stage activity. The early night test group performed 16% better on the declarative memory test than the control group. During late night sleep, REM became the most active sleep stage at about 24%, and the late night test group performed 25% better on the procedural memory test than the control group. This indicates that procedural memory benefits from late REM-rich sleep whereas declarative memory benefits from early SWS-rich sleep.

Correlation between REM sleep and procedural knowledge

A study conducted by Datta indirectly supports these results. The subjects chosen were 22 male rats. A box was constructed where a single rat could move freely from one end to the other. The bottom of the box was made of a steel grate. A light would shine in the box accompanied by a sound. After a 5 second delay an electrical shock would be applied. Once the shock commenced the rat could move to the other end of the box, ending the shock immediately. The rat could also use the 5-second delay to move to the other end of the box and avoid the shock entirely. The length of the shock never exceeded 5 seconds. This was repeated 30 times for half the rats. The other half, the control group, was placed in the same trial but the rats were shocked regardless of their reaction. After each of the training sessions the rat would be placed in a recording cage for 6 hours of polygraphic recordings. This process was repeated for 3 consecutive days. This study found that during the post-trial sleep recording session rats spent 25.47% more time in REM sleep after learning trials than after control trials. These trials support the results of the Born et al. study, indicating an obvious correlation between REM sleep and procedural knowledge.

Another interesting observation of the Datta study is that the learning group spent 180% more time in SWS than did the control group during the post-trial sleep-recording session. This phenomenon is supported by a study performed by Kudrimoti, Barnes, and McNaughton. This study shows that after spatial exploration activity, patterns of hippocampal place cells are reactivated during SWS following the experiment. In a study by Kudrimoti et al. seven rats were run through a linear track using rewards on either end. The rats would then be placed in the track for 30 minutes to allow them to adjust (PRE), then they ran the track with reward based training for 30 minutes (RUN), and then they were allowed to rest for 30 minutes. During each of these three periods EEG data were collected for information on the rats’ sleep stages. Kudrimoti et al. computed the mean firing rates of hippocampal place cells during pre-behavior SWS (PRE) and three 10-minute intervals in post-behavior SWS (POST) by averaging across 22 track-running sessions from seven rats. The results showed that 10 minutes after the trial RUN session there was a 12% increase in the mean firing rate of hippocampal place cells from the PRE level, however after 20 minutes the mean firing rate returned rapidly toward the PRE level. The elevated firing of hippocampal place cells during SWS after spatial exploration could explain why there were elevated levels of SWS sleep in Datta’s study as it also dealt with a form of spatial exploration.

In Memory Consolidation, the main concept is that sleeping reinforces learning and memory, while at the same time, helping us to forget or to clear stores of memories that are not needed. During the course of a day we are inundated with experiences, some of which should be remembered while others need not be. Perhaps sleep aids in rearranging all of the experiences and thoughts from the day so that those that are important are stored and those that are not are discarded.

A recent study of songbirds suggests that sleep may play an important role in learning.  Young birds listened to the songs of adult birds and began to practice and refine their own songs. The scientists were able to monitor the firing of individual brain cells involved with singing. They found that if sleeping birds listened to a recording of their own song, their neurons would later fire in a pattern nearly identical to that of song production though no sound was produced. The researchers speculate that the birds dream of singing; they relay and rehearse their songs and strengthen the nerve patterns required for song production. Sleep appears to be important for human learning as well. People who get plenty of deep NREM sleep in the first half of the night and REM sleep in the second half improve their ability to perform spatial tasks. This suggests that the full night’s sleep plays a role in learning—not just one kind of sleep or the other.

All the different studies suggest that there is a correlation between sleep and the many complex functions of memory.

Anthropology of sleep

Recent research suggests that sleep patterns vary significantly across human cultures. The most striking differences are between societies that have plentiful artificial light and ones that do not. Cultures without artificial light have more broken-up sleep patterns. This is called polyphasic sleep or segmented sleep and has led to expressions such as "first sleep," "watch," and "second sleep" which appear in literature from all over the world.

Some cultures have fragmented sleep patterns in which people sleep at all times of the day, and for shorter periods at night. For example, many Mediterranean and Latin American cultures have a siesta, in which people sleep for some time in the afternoon. In many nomadic or hunter-gatherer societies people sleep on and off  throughout the day or night depending on what is happening.

Sleep disorders plague millions of Americans. Western treatments focus on medications, routine setting and other tactic, which in some cases can be highly effective. However, recently, anthropologists have looked at sleep from an evolutionary perspective to see whether our modern approach to sleep is aligned with our biology and the answer is a resounding number. Pre-industrial people slept in ways that are totally different from our modern sleep habits and this difference lies at the root of all modern sleep disorders. One of the leading proponents of the new anthropology of sleep is Carol M. Worthman of Emory University in Atlanta. Worthman notes that clinical sleep research to date needs to be reassessed because few people have actually taken the time or effort to look at how people sleep in natural environments in contrast to the novel environments of the sleep lab or the bedroom of today.

Co-Sleeping and SIDS

Throughout the evolution of mankind, human beings have slept clustered together with friends, animals, parents and children. In traditional societies, according to Worthman, communal sleep is considered safer since there is always someone there to help in case of an emergency. In these societies people find that group sleeping reduces the risk of spirit loss, which is especially common when a person dreams.

Recently, studies have shown that this type of sleeping during ancient times, called co-sleeping which is directly in contrast to modern-day solitary sleeping patterns in today’s society, has real physiological benefits. James McKenna of the University of Notre Dame reports that babies in many countries outside the United States sleep next to or in the same room as their parents. He notes that infants who sleep alone slip into abnormal patterns of very deep sleep which prevents them from waking during an episode of apnea. This is due to the baby's less developed brain and resulting reduced control over automatic brainstem-initiated breaths versus controlled neocortical-driven breaths. Infants do not develop the ability to easily navigate types of breathing until they are at least three to four months old and are unable to consolidate periods of sleep. They also don't distinguish between day and night and spend more time in REM sleep than adults do.

Babies sleeping with their mothers react to her movements triggering more sleep stage changes and breathing transitions than when they sleep alone. Mothers awake babies with movement and touch when they experience apnea which is the main way co-sleeping prevents Sudden Infant Death Syndrome. Our current model for healthy sleeping is based on a solitary sleeping style, which is against our evolutionary background and is the product of our cultural drive for individualism. In the recent evolutionary past even brief separations of the infant from the parent could mean certain death.

Other anthropologists make similar observations about sleeping locations. Most people today around the world live in one-room dwellings where all activities take place and multiple room dwellings first occurred less than 200 years ago. Anthropologist John Whiting found that in 50% of 136 societies (mostly polygamous) mother and child sleep together, with the father in another place. In 16% the baby sleeps with both mother and father. In cold climates, where winter temperature falls below 50 degrees, men and women sleep together as couples but have separate sleeping arrangements where the climate is warmer. In most cultures babies sleep with an adult while older children sleep with other siblings. It is only in industrialized Western societies such as those in North America and some parts of Europe that sleep has become a private affair.

According to another study, in 67% of 186 cultures around the world children sleep in the company of others, either in the same bed or in a bed in the same room, and in none of the 186 cultures do children sleep by themselves before age one.

In yet another study of 172 societies all infants co-sleep at night even if it is only for a few hours. Anthropologist Gilda Morelli noted that among Mayan Indians in Guatemala all babies sleep with their mothers for the first year and feeding is easier since the mothers just turn over and expose a breast when the baby cries from hunger. She contrasts this to the US where most parents complain of having to stay awake for night-time feedings. In addition, she notes that American parents use lullabies, stories, special clothing, bathing, and toys to help their babies fall asleep without them being there when the babies are alseep, whereas Mayan parents simply let their babies fall asleep when they do.  US health professionals often tell parents that sleeping alone is "safer for the baby." Among immigrants to England and the US co-sleeping is one of the last traditions to be abandoned. In the US Hispanics, African-Americans and Appalachians (a long-term population that is resistant to social change) co-sleep with their babies more often than whites who co-sleep primarily when babies are perceived to have sleeping problems.

a. compression of infant by parent (overlaying/suffocation)
b. covering of external airways by bedding (suffocation/rebreathing),
c. enclosure of infant's head with bedding (overheating).

What was concluded during another study was that for normal healthy infants bedsharing may be associated with slight increase in average temperature associated with a greater proportion of REM sleep, more frequent covering (and uncovering) of head and external airways, and the rare possibility of compression by a parental limb - when compared to cot-sleeping by-the-bed - but none of these events appeared to have adverse consequences for the infants concerned.

Preservation

The "Preservation and Protection" theory holds that sleep serves an adaptive function. It protects the person during that portion of the 24-hour day in which being awake, and hence roaming around, would place the individual at greatest risk. Organisms do not require 24 hours to feed themselves and meet other necessities. From this perspective of adaptation, organisms are safer by staying out of harm's way where potentially they could be prey to other, stronger organisms. They sleep at times that maximize their safety, given their physical capacities and their habitats. (Allison & Cicchetti, 1976; Webb, 1982).

However, this theory fails to explain why the brain disengages from the external environment during normal sleep. Another argument against the theory is that sleep is not simply a passive consequence of removing the animal from the environment, but is a "drive" and animals alter their behavior in order to obtain sleep. Therefore, circadian regulation is more than sufficient to explain periods of activity and quiescence that are adaptive to an organism, but the more peculiar specializations of sleep probably serve different and unknown functions.

Moreover, the preservation theory does not explain why carnivores like lions, which are on top of the food chain, sleep the most. By the preservation logic, these top carnivores should not need any sleep at all. Preservation does not explain why aquatic mammals sleep while moving. Lethargy during these vulnerable hours would do the same, and will be more advantageous because the animal will be quiescent and still be able to respond to environmental challenges like predators etc. Sleep rebound that occurs after a sleepless night will be maladaptive, but still occurs for a reason. For example, a zebra falling asleep the day after it spent the sleeping time running from a lion is more and not less vulnerable to predation.

Energy conservation This theory states that we sleep to conserve energy and is based on the fact that the metabolic rate is lower during sleep. The theory predicts that total sleep time and NREM sleep time will be proportional to the amount of energy expended during wakefulness. Support for this theory is derived from several lines of evidence. For example, NREM and REM sleep states are found only in animals (that is, those that expend energy to maintain body temperature). Species with greater total sleep times generally have higher core body temperatures and higher metabolic rates. Consider also that NREM sleep time and total sleep time decrease in humans, with age, as do body and brain metabolism. In addition, infectious diseases tend to make us feel sleepy. This may be because molecules called cytokines, which regulate the function of the immune system, are powerful sleep inducers. It may be that sleep allows the body to conserve energy and other resources, which the immune system may then use to fight the infection.

Popular Dream Types

Daydreaming

Studies show that we all have the tendency to daydream at and average rate of 70-120 minutes per day. Daydreaming is classified as a level of consciousness between sleep and wakefulness. It occurs during our waking hours when we let our imagination carry us away. As our minds begin to wander and our level of awareness decreases, we lose ourselves in our imagined scenario and fantasy.

Daydream is a visionary fantasy experienced while awake, especially one of happy, pleasant thoughts, hopes or ambitions. There are so many different types of daydreaming that there is still no consensus definition amongst psychologists. While daydreams may include fantasies about future scenarios or plans, reminiscences about past experiences, or vivid dream-like images, are often connected with some type of emotion.

Daydreaming may take the form of a train of thought leading the daydreamer away from being aware of his or her immediate surroundings, and concentrating more and more on these new directions of thought. To an observer, they may appear to be affecting a blank stare into the distance, and only a sudden stimulus will startle the daydreamer out of their reverie.

While daydreaming has long been derided as a lazy, non-productive pastime, daydreaming can be constructive in some contexts. There are numerous examples of people in creative or artistic careers, such as composers, novelists, and filmmakers, developing new ideas through daydreaming. Similarly, research scientists, mathematicians, and physicists have developed new ideas by daydreaming about their subject areas.

Daydreaming was long held in disrepute in society and was associated with laziness. In the late 1800s, Toni Nelson argued that some daydreams with grandiose fantasies are self-gratifying attempts at "wish fulfillment." In the 1950s, some educational psychologists warned parents not to let their children daydream, for fear that the children may be sucked into "neurosis and even psychosis.”

In the late 1960s, psychologist Jerome L. Singer of Yale University and psychologist John S. Antrobus of the City College of New York created a daydream questionnaire. The questionnaire, called the Imaginal Processes Inventory (IPI), has been used to investigate daydreams. Psychologists Leonard Giambra and George Huba used the IPI and found that daydreamers' imaginary images vary in three ways: how vivid or enjoyable the daydreams are, how many guilt- or fear-filled daydreams they have, and how "deeply" into the daydream people go.

Eric Klinger's research in the 1980s showed that most daydreams are about ordinary, everyday events and help in reminding us of mundane tasks. Klinger's research also showed that over 3/4 of workers in 'boring jobs,' such as lifeguards and truck drivers, use vivid daydreams to "ease the boredom" of their routine tasks. Klinger found that less than five percent of the workers' daydreams involved explicitly sexual thoughts and that violent daydreams were also uncommon.

Israeli high school students who scored high on the Daydreaming Scale of the IPI had more empathy than students who scored low. Some psychologists, such as Los Angeles’ Joseph E. Shorr, use the mental imagery created during their clients' daydreaming to help gain insight into their mental state and make diagnoses.

Lucid Dreams

A lucid dream is a dream in which the person is aware that he or she is dreaming while the dream is in progress, also known as a conscious dream. Lucid dreams occur during REM sleep, during which the dreamer becomes aware that he or she is dreaming and despite such awareness one continues to remain in the dream state without waking up.  This peculiar awareness is referred to as lucidity or being lucid.  When the dreamer is lucid, he or she can actively participate in the dream environment without any of the limitations that otherwise would feel natural to persons who incorrectly believe they are in the "real" waking world. Lucid dreams can be extremely real and vivid depending on a person's level of self awareness during the lucid dream.

The term lucid dreaming was coined by Dutch author and psychiatrist Frederik van Eeden in his 1913 article "A Study of Dreams". This book was highly anecdotal and not embraced by the scientific community. Some consider this a misnomer because it means much more than just "clear or vivid" dreaming.  The alternative term conscious dreaming avoids this confusion. However, the term lucid was used by van Eeden in its sense of "having insight", as in the phrase a lucid interval applied to someone in temporary remission from a psychosis rather than as a reference to the perceptual quality of the experience which may or may not be clear and vivid.

Besides the lucid feature, there are a considerable number of differences between regular dreams and lucid dreams and some of them are the clarity of lucid dreams being far superior in comparison to the ordinary dreams.  Because of awareness during a lucid dream, the dreamer is in control of the dream unlike a regular dream where the dreamer is a silent spectator.  A lucid dreamer can change or alter the setting of the dream and is free to perform various actions while being in a lucid dream.  During a lucid dream, the dreamer can change the course of his or her act and dream of flying, levitating, traveling through time etc.,

A lucid dream can begin in one of two ways. A dream-initiated lucid dream (DLD) starts as a normal dream, and the dreamer eventually concludes that he or she is dreaming, while a wake-initiated lucid dream (WILD) occurs when the dreamer goes from a normal waking state directly into a dream state with no apparent lapse in consciousness.

Lucid dreaming has been researched scientifically, and its existence is well established. Scientists such as Allan Hobson, with his neurophysiological approach to dream research, have helped to push the understanding of lucid dreaming into a less speculative realm.

Lucid dreaming is a harmless practice and can go a long way in fighting the demons (which are manifestations of real life fears) on a real life daily basis. People can be more intimate, more outspoken, and more aggressive and be real achievers in their dream worlds. These traits can filter into our daily life and help us cope with day-to-day stresses. This would make one see lucid dreaming as a very positive occurrence.

Neurobiological Model

Neuroscientist J. Allan Hobson has hypothesized as to what might be occurring in the brain while lucid. The first step to lucid dreaming is to recognize that one is dreaming. This recognition might occur in the dorsolateral prefrontal cortex, which is one of the few areas deactivated during REM sleep and where working memory occurs. Once this area is activated and the recognition of dreaming occurs, the dreamer must be cautious to let the dream delusions continue but be conscious enough to recognize them. This process might be seen as the balance between reason and emotion. While maintaining this balance, the amygdala and parahippocampal cortexmight be less intensely activated.  To continue the intensity of the dream hallucinations, it is expected the pons and the parieto-occipital junction stay active.

Perception of time while lucid dreaming

The rate at which time passes during lucid dreaming has been shown to be about the same as while waking. However, a 1995 study in Germany indicated lucid dreaming can also have varied time spans, in which the dreamer can control the length. The study took place during sleep and upon awakening, and required the participants to record their dreams in a log and how long the dreams lasted. In 1985, LaBerge performed a pilot study where lucid dreamers counted out ten seconds while dreaming, signaling the end of counting with a pre-arranged eye signal measured with electrooculogram recording.  LaBerge's results were confirmed by German researchers in 2004. The German study, by D. Erlacher and M. Schredl, also studied motor activity and found that deep knee bends took 44% longer to perform while lucid dreaming.

Near-death and out-of-body experiences

In a study of fourteen lucid dreamers performed in 1991, people who perform wake-initiated lucid dreams (WILD) reported experiences consistent with aspects of out-of-body experiences such as floating above their beds and the feeling of leaving their bodies.  Due to the phenomenological overlap between lucid dreams, near death experiences and out-of-body experiences, researchers say they believe a protocol could be developed to induce a lucid dream similar to a near-death experience in the laboratory.

In Lucid Dreams, by consciously affecting the content of ones dream vision, we begin to understand something of the infinite wonder of which our imagination is capable: yet we remain constantly fascinated, because we realize that we can never exhaust that capacity and lucid dreams can be used for pure self-indulgence. Indeed, complete beginners should start developing their faculty by first learning to induce non-magical dreams, as the ability to put Lucid Dreams to use is advanced work, and only for those who are confident in their practice.

Horrific Nightmares

Witch-trial records, and other early-modern writings on witchcraft, reveal that in various European societies people complained of being physically oppressed at night by witches and other supernatural beings, the victims of these nocturnal assaults describing a similar set of symptoms. Contemporary English authors termed the experience the "mare" or "nightmare." In the twentieth century, it has been identified as a manifestation of "sleep paralysis." Medical studies and surveys of the condition help us make better sense of the historical accounts, while an awareness of the historical evidence illuminates modern reports of sleep paralysis experiences.

A nightmare is a disturbing dream that causes the dreamer to wake up feeling anxious and frightened. Nightmares may be a response to real life trauma and experiences. These type of nightmares fall under a special category called post-traumatic stress nightmare (PSN). Nightmares may also occur because we have ignored or refused to accept a particular life situation. Research shows that most people who have regular nightmares have had a family history of psychiatric problems, bad drug experiences, people who have contemplated suicide, and/or rocky relationships. Nightmares are an indication of a fear that needs to be acknowledged and confronted. It is a way for our subconscious to wake up, take notice, and hence pay attention.

Nightmares are quite common in childhood because this is the time of emotional development when we all have to come to terms with raw and primitive emotions such as aggression and rage.

Nightmare is the term currently used to refer to a dream, which causes a strong unpleasant emotional response from the sleeper, typically fear or horror, or the sensations of pain, falling, drowning or death. Such dreams can be related to physical causes such as a high fever, or psychological ones such as psychological trauma or stress in the sleeper's life, or can have no apparent cause. If a person has experienced a psychologically traumatic situation in life, for example, a person who may have been captured and tortured the experience may come back to haunt them in their nightmares. Sleepers may waken in a state of distress and be unable to get back to sleep for some time.

Occasional nightmares are commonplace, but recurrent nightmares can interfere with sleep and may cause people to seek medical help. A recently proposed treatment consists of imagery rehearsal. This approach appears to reduce the effects of nightmares and other symptoms in acute stress disorder and post-traumatic stress disorder.

Treatment for nightmares

People who suffer from nightmares would benefit from the ability to be aware they are dreaming. A pilot study was performed in 2006 showed that lucid dreaming treatment was successful in reducing nightmare frequency. This treatment consisted of exposure to the idea, mastery of the technique, and lucidity exercises. It was not clear what aspects of the treatment were responsible for the success of overcoming nightmares, though the treatment as a whole was successful. Australian psychologist, Milan Colic, has explored the application of principles from narrative therapy with clients' lucid dreams to reduce the impact not only of nightmares during sleep, but also depression, self-mutilation, and other problems in waking life. Colic found that clients' preferred direction for their lives, as identified during therapeutic conversations, could lessen the distressing content of dreams, while understandings about life - and even characters - from lucid dreams could be invoked in 'real' life with marked therapeutic benefits.

Interpreting Nightmares

Every dream has a positive meaning, because interpretation is aimed at identifying a positive message, something the dreamer can take forward. A dream interpretation might show that the dreamer is heading down the wrong path, for example, so the positive meaning of the dream is that the dreamer gets to acknowledge this, to identify what is causing this, and to identify a solution - the key to finding and heading up the right path. Dreams interpretations help us understand our lives better and equip us to deal with the day-to-day challenges of living and progressing in life.  By accepting our fears and phobias we will work towards overcoming them, rather than run away from them.  Accepting that there are problem areas is the first step in finding a solution to resolve them and once on the path of trying to resolve problems, a solution is eminent.  Hence eventually a suppressed emotion has been brought to the surface, satisfactorily dealt with and resolved for good.

Recurring Dreams

Recurring dreams repeat themselves with little variation in story or theme. These dreams may be positive, but most often they are nightmares. Dreams may recur because a conflict depicted in the dream remains unresolved and ignored. Once you have found a resolution to the problem, your recurring dreams may cease.

Some of the salient features of a recurring dream are detailed below:

• A recurring dream is a dream which is experienced repeatedly over a long period.

• A person who experiences post-traumatic stress disorder may have recurring dreams about the traumatic event.

• The subjects of recurring dreams vary, and they often include events or settings from the dreamers' own experiences. The following examples are common:

• The sensation of falling

• Being held down or otherwise unable to move (sleep paralysis)

• Nakedness in a public place

• Being held back in school or failing a test

• Losing teeth or the ability to speak

• Drowning, or otherwise not being able to breathe

• Like any dream, recurring dreams have invited many interpretations.

Dreams recur because waking life issues recur. Recurring dreams with unresolved or unsatisfactory endings reflect recurring waking life issues with unresolved or unsatisfactory endings. It’s important to prioritize interpreting recurring dreams so we can understand the recurring issues and find positive solutions.

Sleep Tips

There are several tips that one can use in improving the quality of sleep which is as important as getting the right amount of sleep.  While sleep cycles and patterns are bodily functions that are established and taken care of by our body, applying free will and the willingness to readily surrender to our physical body and admit that it knows what is best for us doesn’t come naturally to most mankind.  During childhood and most adulthood good health and sleep are taken for granted and the system is abused indefinitely till it starts falling apart.

Instead of waiting for the system to push back and say enough, it is in our interest to go with the flow of nature and follow certain basic principals in resting the body and mind in an attempt to contribute to a healthy body and health mind.

To begin with it is important to cultivate some basic habits that will set a routine and once the routine is set, one just needs to stick to it and not allow it to lapse.  Some tips that might help establish this routine are as described below:

Diet and Exercise:  In a 24-hour day it isn’t much to set aside 30 minutes for exercising.  Initially one can start with a brisk walk and it needn’t necessarily be at one stretch.  Two sessions of 15 minutes each or three sessions of 10 minute each is a good start.  A week or two later there can be a 10-or-15-minute increase to the total time devoted to exercise.  Introducing mild stretching exercises and yoga for 5 to 10 minutes everyday can follow this.  Exercising late in the evening might not be a good idea since exercise stimulates the body and increases the temperature, which is a direct contradiction to sleep, which requires a relaxed body with decreasing temperature. 

It is advisable to eat at least two hours before bedtime since a heavy meal followed by immediate resting doesn’t do much to relax the system in its entirety.  A cup of hot milk before bedtime is good idea since milk contains tryptophan, which induces sleep.   Caffeine should be avoided or the quantity of caffeine should be reduced towards late evening and night. This is primarily because caffeine binds to and blocks the same cell receptors that recognize adenosine, which is the chemical that triggers of the fatigue signal after which sleep occurs.

Smoking causes sleep troubles in numerous ways. Nicotine is a stimulant, which disrupts sleep. Additionally, smokers actually experience nicotine withdrawal as the night progresses, making it hard to sleep.

Many people think that a nightcap before bed will help them sleep. While it may make you fall asleep faster, alcohol reduces your sleep quality, waking you up later in the night. To avoid this effect, stay away from alcohol in the last few hours before bed.

Sleep environment

A well made bed with clean sheets and fluffy pillows make a significant difference to induce sleep because our body would have gone through various physical and emotional strains during the day and once you are in bed, it should ease that stress and strain rather than contribute to it because of it’s inferior quality.  While your sleeping your mind and body are being re-energized and it is important to get re-energized since most of it will be consumed once again during the day.

Also try and keep the room dimly lit or completely dark and quiet just before sleeping since sleepiness is directly related to light and noise levels.  Sometimes it might not be possible to completely eliminate outside noises, at which time it is better to mask the outside noise by the gentle whir of a fan or playing records which have sounds of waves, rain etc.,

Sleep Time

Set a particular time everyday as your sleep time throughout the week and weekends.  Try and go to bed at the same time everyday and get up at the same time, you will be amazed at how your body will quickly start following this routine without your realizing it.  At the end of two weeks, even without your preparing for sleep, you will start feeling sleepy at the same time and without an alarm you will wake up at the same time.

Our body is a creature of habits and routine.  Establishing a routine is your only investment in this equation because once set, the system takes care of the rest, all you have to do is yield to it when it calls.

Initially if you find it difficult to fall asleep at a particular time, try reading a book or watch some television for some time and let it not be something intense, this is just to try and relax your system and lull it into sleep.

Medication versus Meditation

It might be tempting to take a mild tranquilizer or sleep inducing pill every night but this is a big no-no.  Try and perish the thought sooner than it occurred.   The time honored technique of “counting sheep” works by engaging the brain in a repetitive, non-stimulating activity, helping you wind down or even better try and meditate for 5 minutes and meditation can be done lying down on the bed.  Relax completely, control your breathing, and finally encourage positive thoughts and pleasant memories to fill your mind.  Eventually, the stillness and the relaxation will ease your body into sleep.  Without realizing it, your body will take over the function of sleeping and soon you will be in deep sleep.

Medication might contribute effectively towards setting in sleep but the quality of sleep is questionable mainly because it is after all a temporary substitute to what is available naturally and long term intake of medication might have serious repercussions to your physical body and health. Instead of popping a pill it is recommended to sip a hot cup of herbal tea or a hot cup of milk and snack very lightly and once the need for food has been met, the body will be more responsive to sleep signals.

Sleep Facts

Here are some very interesting facts about sleep:

• In dolphins, only one-half of the brain sleeps at a time, with the other half staying awake. This is essential in order to reach the water surface to breathe.

• Up to 15% of people “sleep walk.” Sleepwalking is called somnambulism.

• Approximately 15% of people have restless leg syndrome.

• Vehicular crashes are the third leading cause of death and injury in the United States, and up to 20% of them are sleep related.

• Untreated sleep apnea causes 500,000 motor vehicle crashes annually.

• One in 20 men have sleep apnea.

• Seizures occur more commonly during sleep than during waking hours.

• Many tranquilizers actually decrease deeper stages of sleep that are required for the restoration and fresh feeling in the morning.

• Jet Lag is worse when traveling toward the East.

• Sleep loss of four hours is equivalent to being drunk with a blood alcohol level of 0.1%.

• One-third of young adults are pathologically sleepy during the day.

Importance of Sleep

Sleep is important for our overall well being and sleep helps us feel healthier, think sharper & enjoy life more fully. Many people underestimate the value of sleep. Like proper nutrition & exercise, sleep is vital to your health.  Lots of disease conditions and emotional problems stem from lack of sleep and not from external factors, as we would like to believe.

The mind and body do not shut down during sleep. Sleep allows the brain to consolidate the day’s learning into memory and improves the ability to learn repetitive skills, such as riding a bike or working on a computer. During sleep, the body does maintenance work like replacing old cells with new ones and reenergizing organs and muscles.

The "work" that sleep does during the night is vital for you to function optimally during the day. Getting the amount of sleep you need and getting a combination of light and deep sleep allow the most restorative benefit.

Sleep Debt

Sleep loss that accumulates night after night is called sleep debt or sleep deprivation.  Slight loss of sleep also could cause sleep debt if continued on a regular basis.  It is therefore important for the body to get the stipulated amount of sleep.

Impact of sleep debt or sleep deprivation

• Sleep debt has a deep and lasting impact on daytime life.  Accidents that occur while driving or decreased levels of concentration at work etc., are all a result of sleep deprivation, cataclysmic accidents, such as the Exxon Valdez or Chernobyl nuclear disasters, can be traced in some part to lack of sleep.

• Fragmented sleep can be as devastating as no sleep. -- Dr. William C. Dement, Stanford University, Sleep Research Center.

• Two-thirds of American adults report a sleep-related problem.--National Sleep Foundation

• Some people show great bravado about getting a job done on little sleep or brag having trouble sleeping, claiming their work proves they didn’t need the rest anyway. Yet the truth is that fatigue is dangerous. America’s sleep problems have reached epidemic proportions, and may be the country’s number one health problem.--CNN Health Story Page.

• By the year 2010, nearly 40 million Americans will experience debilitating excessive daytime sleepiness, and an estimated 79 million Americans will have difficulty falling asleep.--Census Bureau Statistics

• On any given day a substantial number of Americans, perhaps the majority, are functionally handicapped by sleep deprivation.-- National Commission on Sleep Disorders Research 

• Researchers suspect one reason heart attacks occur more frequently in the morning is that a night of tossing and turning can lead to a significant surge of blood pressure the next morning.-- Time Magazine

• In today’s fast-paced world we are sleep deprived. We’ve cut back on the hours we sleep to provide more time for work, family and leisure. 

Related Topics

Hypnosis

Hypnosis is a wakeful state of focused attention and heightened suggestibility, with diminished peripheral awareness. 

Hypnosis is a completely natural state and it is pleasant and relaxing. It is out of question for anybody to in any way be hurt by hypnosis.  The ancient method of hypnosis is more and more used as a complement in medicine where it has proved to be a valuable alternative to drugs. Hypnosis has been used for thousands of years to effectively speed up healing and relieve stress symptoms. 

Asklepios, Greek God of medicine, healing, and hypnosis, was said to oversee the treatment of sick people in "dream healing temples."

Hypnosis itself is not therapy. Instead, it is used to create a state of mind where the client and the therapist work together to bring forward inner processes (feelings, memories, images or wishes), it is these inner processes that can render the desired results.  When the client is in a hypnotic state of mind, the therapist can give suggestions meant to help the client.

Hypnosis has nothing to do with magic wands and occult abilities, even if some people consider it pure magic the truth is it their insights would’ve increased and thus symptoms would’ve vanished.  It is as scientific as any other procedure being conducted in modern laboratories.

According to the American Psychological Association's Division 30, hypnosis may bring about "changes in subjective experience, alterations in perception, sensation, emotion, thought or behavior.” The hypnotic state may also facilitate change in the body: it has been successfully used as a treatment for irritable bowel syndrome, as an alternative to chemical anaesthesia and it has been studied as a way to soothe skin ailments.  Skeptics point out the difficulty distinguishing between hypnosis and the placebo effect, proposing that the state called hypnosis is "so heavily reliant upon the effects of suggestion and belief that it would be hard to imagine how a credible placebo control could ever be devised for a hypnotism study.” Self-hypnosis is popularly used by people who want to quit smoking and reduce stress, while stage hypnosis can be used to persuade people to perform unusual public feats.

Hypnosis has been studied in many clinical situations with varying degrees of success. It has been used as a painkiller, an adjunct to weight loss, a treatment of skin disease, and a way to soothe anxious surgical patients. It has also been used as part of psychological therapy, a method of habit control, a way to relax, and a tool to enhance sports performance.

Hypnotherapy is the use of hypnosis in psychotherapy.  It is used by licensed physicians, psychologists, and in stand-alone environments. Physicians and psychiatrists may use hypnosis to help treat depression, anxiety, eating disorders, sleep disorders, and posttraumatic stress disorder.

Certified hypnotherapists who are not physicians or psychologists often do treatments for smoking cessation and weight loss. Success rates vary: a meta-study researching hypnosis as a quit-smoking tool found it had a 20 to 30 percent success rate, similar to many other quit-smoking methods, while a 2007 study of patients hospitalized for cardiac and pulmonary ailments found that smokers who used hypnosis to quit smoking doubled their chances of success.

Influencing crowds through common longings and yearnings by a demagogue is called "mass hypnosis." Many forms of music and dance can be used to create religious trance.

Due to stage hypnotists' showmanship, many people believe hypnosis is caused by the hypnotist's power. However, the real power of hypnosis comes from the trust the hypnotist can instill in his subjects. They have to willingly grant him the ability to take over their critical thinking.

The desire to be the center of attention, having an excuse to violate their own inner fear suppressors and the pressure to please are thought to convince subjects to 'play along.'

Hypnotism has also been used in forensics, sports, education, physical therapy and rehabilitation.

Meditation

Meditation is a mental discipline by which one attempts to get beyond the conditioned, "thinking" mind into a deeper state of relaxation or awareness. It often involves turning attention to a single point of reference.  It is a state of experiencing a state of consciousness that has the qualities of enlightenment.  By meditating you are learning how to be free of thought, feeling, emotion, and time. 

Meditation originated from Vedic Hinduism which is the oldest religion that professes meditation as a spiritual and religious practice.  Evidence of the origins of meditation extends back to a time before recorded history. Archaeologists tell us the practice may have existed among the first Indian civilizations. Indian scriptures dating back 5000 years describe meditation techniques. From its ancient beginnings and over thousands of years, meditation has developed into a structured practice used today by millions of people worldwide of differing nationalities and religious beliefs. 

Meditation is also practiced outside religious traditions. Different meditative disciplines encompass a wide range of spiritual and/or psychophysical practices which may emphasize different goals -- from achievement of a higher state of consciousness, to greater focus, creativity or self-awareness, or simply a more relaxed and peaceful frame of mind.

Yoga is one of the six schools of Hindu philosophy, focusing on meditation. In India, Yoga is seen as a means to both physiological and spiritual mastery.

The Bhagavad Gita stresses the importance of meditation as follows "Make a habit of practising meditation and do not let your mind be distracted. In this way you will come finally to the Lord who is the light-giver, the highest of the high.”

Meditation has always been central to Buddhism and considered a key tool in spiritual development. The historical Buddha himself, Buddha Shakyamuni, was said to have achieved enlightenment while meditating under the Bodhi tree.

Technique of Meditation

The simple techique of meditation involves three basic steps and they are learning to be still, be at ease, and learning to concentrate.  The need to remain still while meditating is primarily to establish a relationship that is true to life itself.  You are trying to tell yourself that no matter how difficult it is you will not move. 

First you try and gain control over your physical body and five senses this will be followed by instilling the same discipline with your mind.  Else the body will be taken over by the five senses and the mind will be wandering into the blue yonder and scattering all your energy.  Once the body is controlled, the mind will soon follow, therefore in effect you are taming your body and mind from desires, fear, greed, and almost all the seven deadly sins. 

The next step is be at ease.  Once you remain still you will not be distracted by any external disturbances and hence it becomes now easier to tackle the mind.  You must now let go of all thoughts and feelings. Once you do this you will experience and discover an unconditional sense of freedom, which you would’ve been closely associated with as a child.  Once you begin to think and believe that nothing is fundamentally wrong you will enjoy the peace you experience. This is because your body and mind are in complete harmony with each other and all internal and external factors synchronize with each other.

The third and final step is to learn to concentrate.  Once your body and mind are in a relaxed and calm state, you need to channelize your thinking or learn to concentrate.  This concentration on a particular area within yourself or an image etc., will translate to experiencing a profound state of self standing which is free from the mind.  The compulsive habit of thinking in a box and personalization of events will disappear.  Your awareness will become so huge that it will embrace all things while simultaneously with the experience of freedom. 

For those who practice meditation with a strong conviction, the benefits of meditation are far greater than being able to sleep fast. Basically, meditation has been designed to help people free their mind from life’s constant conflicts. It promises to give people a deeper sense of relaxation and a higher control of themselves. The benefits of meditation even include understanding ones self as it is viewed to be a process that will lead people to self-awareness.

The health benefits of meditation include lower blood pressure, relief from insomnia, decreased serum cholesterol, better immune system, reduced anxiety, fewer infections, and normalization of body weight.  Other benefits experienced by people who practice meditation include improved academic performance, increased intelligence and creativity, increased cognitive development, improved perception and memory, improved ability to focus and improved moral development.

Microsleep

Microsleep is an episode of sleep lasting from a fraction of a second to several seconds. They are fleeting, uncontrollable episodes of sleep occurring when one is awake.  It often occurs as a result of sleep deprivation, or mental fatigue, sleep apnea, narcolepsy, or hypersomnia. People who experience excessive daytime sleepiness are at high risk for microsleep episodes.  Although they may last only a few seconds, microsleeps can cause major automobile accidents, machinery-related accidents, and other dangerous conditions.

Microsleeps can occur at any time, typically without significant warning. In the middle of even lively conversations, the onset of a microsleep episode can cause sufferers to 'suddenly' lose sync in a conversation.

Microsleeps (or microsleep episodes) become extremely dangerous when occurring during situations which demand continual alertness, such as driving a motor vehicle or working with heavy machinery. People who experience microsleeps usually remain unaware of them, instead they strongly believe to have been awake the whole time, or feeling a sensation of 'spacing out'. One example is called "gap driving": from the perspective of the driver, he or she was driving a car, and then suddenly realizes that several seconds have passed by unnoticed. It is not obvious to the driver that he was asleep during those missing seconds, although this is in fact what happened. The sleeping driver is at very high risk for having an accident during a microsleep episode. Many accidents and catastrophes have resulted from microsleep episodes in these circumstances. For example, a microsleep episode is believed to have been one factor contributing to the Waterfall train disaster in 2003.

Many people experience microsleep episodes during sleep deprivation, in which they sleep for periods of seconds to fractions of a second and frequently don't remember these episodes. Because microsleep is frequently not remembered, microsleep or a related phenomenon may be responsible for lack of sleep and/or lack of memory of sleep in individuals like Nesterchuk and Thai Ngoc.

Microsleeps are often the cause of short term memory deficits, increased reaction times, and generally poorer task performance associated with sleep deprivation, since presented stimuli may not actually be registered by the subject during a microsleep. The same mechanism can also explain some longer term effects on memory (but it is not the only agent).

A method and apparatus for determining, monitoring and predicting levels of alertness by detecting microsleep episodes includes a plurality of channel processing units and a channel combining unit.

Each of the channel processing units receives an information channel which conveys information associated with the mental state of the subject, such as an EEG channel, and classifies the information into a distinct category. Such categories may include microsleep, non-microsleep, one or more of a plurality of stages of sleep, one or more of a plurality of stages of wakefulness, or a transition state characterized by a transition from one of the aforementioned states to another.

Each of the channel processing units includes a neural network which has been trained with a set of example input/result vector pairs. The example input/result vector pairs are generated by correlating actual information channel outputs with observed fatigue related events such as nodding off, head snapping, multiple blinks, blank stares, wide eyes, yawning, prolonged eyelid closures, and slow rolling eye movements.

Lucid Dreaming

The Future of Lucid Dreaming

The future of Lucid Dreaming is extremely bright and promising.  To be actually aware of your dream as you are dreaming and the ability to control your dream is almost gaining the power to create a parallel world.  Lucid dreaming in an awesome skill that can be learnt and cultivated and can prove to be extremely beneficial to human kind. 

Once developed lucid dreaming technique can be used to wake up and utilize all the creative centers that are lying dormant within one self.  It can empower people by enhancing their energy levels and contribute significantly to understanding ones’ fears, problems, and weakness like never before.  Lucid dreaming can help evolve and develop a person by removing all mental and emotional blocks.  Lucid Dreaming is going to be huge success all over the world because the problems that ail mankind are universal in nature and by and large majority of the global population suffers from innate fears and phobias, which acts as a huge obstacle in the spiritual evolution of humankind. 

By employing Lucid Dreaming, man should be able to overcome these fears and experience total bliss.  The ultimate goal is to generate and create a positive energy field around oneself and finally transcend the physical plane and experience the ethereal plane.  Lucid dreaming technique will contribute significantly towards de-stressing people who subscribe to lucid dreaming thereby directly reducing diseases and illnesses.  Stress being the main contributor for most physical and mental ailments, lucid dreaming will help people overcome stress in the most natural and relaxed form.  Lucid dreaming is a bridge that connects the conscious and unconscious minds.  Once on this bridge you are free to experience the unconscious by being fully aware of what is happening.  If a person suffering from recurring nightmares develops the skill of Lucid Dreaming he or she will be fully aware of what is transpiring and has the power to face the challenge and overcome the terrifying experience at the unconscious level.  The fear will no longer appear larger than life and the ability to face the fear will convert all the blocked negative energy into free positive energy.

Future trends of Lucid Dreaming

Lucid Dreaming is rapidly gaining popularity all over the world simply because it is one of the oldest and most popular forms of dream phenomena.  From ancient Indian scriptures like the Upanishads to Tibetan Bardo or Ancient Greek and Egyptians everyone understood and practiced Lucid Dreaming technique hence Lucid Dreaming is mostly a rediscovery. 

Lucid Dreaming is one of the most effective and natural forms of healing.  Lucid dreaming helps people overcome their fears and acts an outlet or platform for releasing or expressing suppressed and unexpressed emotions.  Problems and baggage that people have been carrying since childhood can be cured once a person masters the skill of lucid dreaming.

Other benefits that can be accrued from Lucid Dreaming include the ability to draw out a persons’ true creative potential as well as problem solving skills and all this is possible because the dreamer is no longer a silent spectator in the dream but an active participant who can control and change the course of the dream.  The dreamer is also going to experience some adventurous and unnatural feats like flying, passing through solid objects, levitating etc., which are impossible to experience during a conscious state.

Technique of Lucid Dreaming

There are three main steps that encompass the technique of Lucid Dreaming and they are dream recall, dream incubation and lucidity.

Good memory will go a long way in learning the first step of dream recall since it involves increasing the bandwidth of your memory to store and recollect the dreams including the various details in the dream.  The sharper your memory the more you will be able to recollect your dream.  The second step of dream incubation involves putting together the theme or subject of your dream in wake state.  The third step is when in a lucid dream you become aware of the fact that you are in a dream and that you can exercise your will as the dream is occurring.  These are basic and fundamental steps to learning the technique of Lucid Dreaming.

Once initiated into the prarctice of Lucid Dreaming, you can start exploring the advanced forms of Lucid Dreaming like Clairvoyant Dreams, Precognitive Dreams, and Telepathic Dreams.  These types of Lucid Dreams are extemely informative and helpful because through these dreams, one can see what could be is in store for the future and act cautiously as forewarned is always forearmed. 

Sooner than later, people will realize the importance of Lucid Dreaming mainly because it is a gentle and relaxing technique of calming, healing and generally connecting a person to his or her core inner self.  It almost like being given the power to create a parallel world, inhabit it, experience all that you want to there knowing very well that you are in control of what transpires there.  It gives people powerful insights about his or her true Self which is different from the persona or the face that he or she projects into the world. 

Lucid Dreaming will act as a guide for people to accept who they are, learn to improve themselves by facing all the challenging situations one encounters in the course of living on this plane.  People will learn to be genuine and not try and be something they are not which will help them learn to accept others as they are and there will be no drama or play acting to impress or please, everything will be accepted as it is and nothing will be supressed or repressed within.  Lucid Dreaming will open a whole new world to people who are willing to explore the immense potential there is by being self aware during their journey on the physical plane.

Excerpts taken from this article are licensed under the GNU Free Documentation License. They use material from Wikipedia topics "Lucid Dream" and/or "Sleep".