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Saturday, July 24, 2010

Lucid Dream

Have you already seen Inception? an American science fiction-action film written, produced, and directed by Christopher Nolan. This film is inspired by the experience of lucid dreaming. What is lucid dream? Have your ever heard or maybe experienced this before? This following are some explanations about Lucid dream.

Hypnos and Thanatos, Sleep and His Half-Brother Death, an 1874 painting by John William Waterhouse

A lucid dream is a dream in which the sleeper is aware that he or she is dreaming. A lucid dreamer can actively participate in and manipulate imaginary experiences in the dream environment. Lucid dreams can seem extremely real and vivid, depending on a person's level of self-awareness during the lucid dream. The term was coined by the Dutch psychiatrist and writer Frederik van Eeden (1860–1932).

A lucid dream can begin in one of two ways. A dream-initiated lucid dream (DILD) starts as a normal dream, and the dreamer eventually concludes it is a dream, 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.

1.Scientific history

The first book to recognize the scientific potential of lucid dreams was Celia Green's 1968 study Lucid Dreams. Green analyzed the main characteristics of such dreams. She reviewed previously published literature on the subject, and incorporated new data from subjects of her own. She concluded that they were a category of experience quite distinct from ordinary dreams, and predicted that they would turn out to be associated with rapid eye movement sleep (REM sleep). Green was also the first to link lucid dreams to the phenomenon of false awakenings.

In the early 1970s, Daniel Oldis of the University of South Dakota leveraged the scientific principle of external sensory incorporation in an attempt to influence dream content and evoke lucidity. Three psychological techniques were employed: subconscious suggestion using a tape played before and during sleep; associative signaling using a muffled bell alarm timed to go off during REM sleep; and classical conditioning using a REM detection circuit and a bright eye-light. The results indicated that lucid dreaming can be facilitated using external cues and psychological methods.

Philosopher Norman Malcolm's 1959 text Dreaming had argued against the possibility of checking the accuracy of dream reports. However, the realization that eye movements performed in dreams affected the dreamer's physical eyes provided a way to prove that actions agreed upon during waking life could be recalled and performed once lucid in a dream. The first evidence of this type was produced in the late 1970s by British parapsychologist Keith Hearne. A volunteer named Alan Worsley used eye movement to signal the onset of lucidity, which were recorded by a polysomnograph machine.

Hearne's results were not widely distributed. The first peer-reviewed article was published some years later by Stephen LaBerge at Stanford University, who had independently developed a similar technique as part of his doctoral dissertation. During the 1980s, further scientific evidence to confirm the existence of lucid dreaming was produced as lucid dreamers were able to demonstrate to researchers that they were consciously aware of being in a dream state (again, primarily using eye movement signals). Additionally, techniques were developed which have been experimentally proven to enhance the likelihood of achieving this state. Research on techniques and effects of lucid dreaming continues at a number of universities and other centers, including LaBerge's Lucidity Institute.

2.Research and clinical applications

Neurobiological model

Neuroscientist J. Allan Hobson has hypothesized what might be occurring in the brain while lucid. The first step to lucid dreaming is recognizing 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. While maintaining this balance, the amygdala and parahippocampal cortex might be less intensely activated. To continue the intensity of the dream hallucinations, it is expected the pons and the parieto-occipital junction stay active.

L'Ange du Foyer ou le Triomphe du Surréalisme by Max Ernst. Surrealist art can capture the disturbing nature of some dreams. Lucid dreaming is a possible nightmare treatment.

Treatment for nightmares

It has been suggested that sufferers of nightmares could benefit from the ability to be aware they are indeed dreaming. A pilot study was performed in 2006 that 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.

Perception of time

The rate at which time passes while lucid dreaming has been shown to be about the same as while waking. However, a 1995 study in Germany indicated that 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.

Awareness and reasoning

While dream control and dream awareness are correlated, neither requires the other—LaBerge has found dreams which exhibit one clearly without the capacity for the other; also, in some dreams where the dreamer is lucid and aware they could exercise control, they choose simply to observe. In 1992, a study by Deirdre Barrett examined whether lucid dreams contained four "corollaries" of lucidity: knowing that dreamt people are indeed dreamt, that objects won't persist beyond waking, that physical laws need not apply, and having clear memory of the waking world, and found less than a quarter of lucidity accounts exhibited all four. A related and reciprocal category of dreams that are lucid in terms of some of these four corollaries, but miss the realization that "I'm dreaming" were also reported. Scores on these corollaries and correctly identifying the experience as a dream increased with lucidity experience.

Near-death and out-of-body experiences

In a study of fourteen lucid dreamers performed in 1991, people who perform wake-initiated lucid dreams operation (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.

Illustration from "The Secret of the Golden Flower". A Chinese book of alchemy and meditation

3.Cultural history

Even though it has only come to the attention of the general public in the last few decades, lucid dreaming is not a modern discovery. A letter written by St. Augustine of Hippo in 415 AD refers to lucid dreaming. In the eighth century, Tibetan Buddhists and Bonpo were practicing a form of Dream Yoga held to maintain full waking consciousness while in the dream state. This system is extensively discussed and explained in the book Dream Yoga and the Practice of Natural Light. One of the important messages of the book is the distinction between the Dzogchen meditation of Awareness and Dream Yoga. The Dzogchen Awareness meditation has also been referred to by the terms Rigpa Awareness, Contemplation, and Presence.

Awareness during the sleep and dream states is associated with the Dzogchen practice of natural light. This practice only achieves lucid dreams as a secondary effect—in contrast to Dream yoga which is aimed primarily at lucid dreaming. According to Buddhist teachers, the experience of lucidity helps us to understand the unreality of phenomena, which would otherwise be overwhelming during dream or the death experience.

An early recorded lucid dreamer was the philosopher and physician Sir Thomas Browne (1605–1682). Browne was fascinated by the world of dreams and described his own ability to lucid dream in his Religio Medici: "... yet in one dream I can compose a whole Comedy, behold the action, apprehend the jests and laugh my self awake at the conceits thereof". Similarly, Samuel Pepys in his diary entry for 15 August 1665 records a dream "that I had my Lady Castlemayne in my arms and was admitted to use all the dalliance I desired with her, and then dreamt that this could not be awake, but that it was only a dream". Marquis d'Hervey de Saint-Denys was probably the first person to argue that it is possible for anyone to learn to dream consciously.

In 1867, he published his book Les Reves et les moyens de les diriger; observations pratiques (Dreams and How to Guide them; Practical Observations), in which he documented more than twenty years of his own research into dreams.

The term lucid dreaming was coined by Dutch author and psychiatrist Frederik van Eeden in his 1913 article "A Study of Dreams".This paper 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.

In the 1950s, the Senoi hunter-gatherers of Malaysia were reported to make extensive use of lucid dreaming to ensure mental health, although later studies refuted these claims.

4.Induction Methods

Many people report having experienced a lucid dream during their lives, often in childhood. Children seem to have lucid dreams more easily than adults. Over time, several techniques have been developed to achieve a lucid dreaming state intentionally. The following are common factors that influence lucid dreaming and techniques that people use to help achieve a lucid dream:

Dream recall

Dream recollection is simply the ability to remember dreams. Good dream recall is often described as the first step towards lucid dreaming. Better recall increases awareness of dreams in general; with limited dream recall, any lucid dreams one has can be forgotten entirely. To improve dream recall, some people keep a dream journal, writing down any dreams remembered the moment one awakes. An audio recorder can also be very helpful. It is important to record the dreams as quickly as possible as there is a strong tendency to forget what one has dreamt. For best recall, the waking dreamer should keep eyes closed while trying to remember the dream, and one's dream journal should be recorded in the present tense. Dream recall can also be improved by staying still after waking up, so the principles of state-dependent memory may apply. Similarly, if the dreamer changes positions in the night, they may be able to recall certain events of their dream by testing different sleeping positions. Another easy technique to help improve dream recall is to simply repeat (in thoughts or out loud) "I shall remember my dreams," before falling asleep. Stephen LaBerge recommends that you remember at least one dream per night before attempting any induction methods.

Wake-initiated lucid dreams (WILD)

The wake-initiated lucid dream occurs when "the sleeper enters REM sleep with unbroken self-awareness directly from the waking state".There are many techniques aimed at entering a WILD. The key to these techniques is recognizing the hypnagogic stage, which is within the border of being awake and being asleep. If a person is successful in staying aware while this stage occurs, they will eventually enter the dream state while being fully aware that it is a dream.

There are key times at which this state is best entered; while success at normal bedtime after having been awake all day is very difficult, it is relatively easy after sleeping for 3–7 hours or in the afternoon during a nap. Techniques for inducing WILDs abound. Dreamers may count, envision themselves climbing or descending stairs, chant to themselves, control their breathing, count their breaths to keep their thoughts from drifting, concentrate on relaxing their body from their toes to their head, or allow images to flow through their "mind's eye" and envision themselves jumping into the image to maintain concentration and keep their mind awake, while still being calm enough to let their bodies sleep.

During the actual transition into the dream state, dreamers are likely to experience sleep paralysis, including rapid vibrations, a sequence of loud sounds, and a feeling of twirling into another state of body awareness, or of "drifting off into another dimension", or like passing the interface between water into air, face front, body first, or the gradual sharpening and becoming "real" of images or scenes they are thinking of and trying to visualize gradually, which they can actually "see", instead of the indefinite sensations they feel when trying to imagine something while wide awake.

Reality testing

Reality testing (or reality checking) is a common method used by people to determine whether or not they are dreaming. It involves performing an action and observing if the results are consistent with results which would be expected in a state of wakefulness. By practicing these tests during waking life, one may eventually decide to perform such a test while dreaming, which may fail and let the dreamer realize that they are dreaming.

• The pain test -- "Pinch me, I think I'm dreaming!" -- is only effective in very few dreams. In Stephen LaBerge's book Exploring the World of Lucid Dreaming it is proven that dreamed action produces real effects on the brain and body. Therefore, if the dreamer pinches itself, it will indeed feel pain but it will be unlikely to induce lucidity, because the schema for pain in the dreamer's brain will activate and the dreamer will feel pain even if there is no real physical stimulus. This same logic applies for other sensations, such as pleasure, heat, cold and a variety of other feelings the dreamer could experience in the waking world.

• Looking at text or one's digital watch (remembering the words or the time), looking away, and looking back. The text or time will probably have changed randomly and radically at the second glance or contain strange letters and characters. (Analog watches do not usually change in dreams, while text and digital watches have a great tendency to do so.) A digital watch or clock may feature strange characters or the numbers all out of order.

• Flipping a light switch. Light levels rarely change as a result of the switch flipping in dreams.

• Looking into a mirror; in dreams, reflections from a mirror often appear to be blurred, distorted, incorrect, or frightening.

• Looking at the ground beneath one's feet or at one's hands. If one does this within a dream the difference in appearance of the ground or one's hands from the normal waking state is often enough to alert the conscious to the dream state.

• If you listen to music while you sleep, listen to see if the lyrics are changed or if the tempo (or speed) of the song changes.

A more precise form of reality testing involves examining the properties of dream objects to judge their apparent reality. Some lucid dreamers report that dream objects when examined closely have all the sensory properties, stability, and detail of objects in the physical world. Such detailed observation relates to whether mental objects and environments could effectively act as substitutes for the physical environments with the dreamer unable to see significant differences between the two. This has implications for those who claim there is a spiritual or supernatural world that might be accessible through out of body experiences or after death.


One problem faced by people wishing to experience lucid dreams is awakening prematurely. This premature awakening can be frustrating after investing considerable time into achieving lucidity in the first place. Stephen LaBerge proposed two ways to prolong a lucid dream. The first technique involves spinning one's dream body. He proposed that when spinning, the dreamer is engaging parts of the brain that may also be involved in REM activity, helping to prolong REM sleep. The second technique is rubbing one's hands. This technique is intended to engage the dreamer's brain in producing the sensation of rubbing hands, preventing the sensation of lying in bed from creeping into awareness. LaBerge tested his hypothesis by asking 34 volunteers to either spin, rub their hands, or do nothing. Results showed 90% of dreams were prolonged by hand rubbing and 96% prolonged by spinning. Only 33% of lucid dreams were prolonged with taking no action.

Other variations on this theme have been proposed by lucid dream enthusiasts, the common basis for all these techniques is to focus on and/or increase ones tactile or sensory engagement with the dream world.

5.Other associated phenomena

Rapid eye movement (REM)

Rapid eye movement sleep
When a person is dreaming, the eyes move rapidly up and down and vibrate. Scientific research has found that these eye movements correspond to the direction in which the dreamer is "looking" in his/her dreamscape; this has enabled trained lucid dreamers to communicate whilst dreaming to researchers by using eye movement signals.

REM Sleep. EEG highlighted by red box. Eye movements highlighted by red line.

False awakening

In a false awakening, one suddenly dreams of having been awakened. Commonly in a false awakening, the room is similar to the room in which the person fell asleep. If the person was lucid, they often believe that they are no longer dreaming and may start exiting the room and start going through a daily routine. This can be a nemesis in the art of lucid dreaming, because it usually causes people to give up their awareness of being in a dream, but it can also cause someone to become lucid if the person does a reality check whenever he/she awakens. People who keep a dream journal and write down their dreams upon awakening sometimes report having to write down the same dream multiple times because of this phenomenon. It has also been known to cause bed wetting as one may dream that they have awoken to go to the lavatory, but in reality are still dreaming. The makers of induction devices such as the NovaDreamer and the REM Dreamer recommend doing a reality check every time you awake so that when a false awakening occurs you will become lucid. People using these devices have most of their lucid dreams triggered through reality checks upon a false awakening.

Sleep paralysis

During REM sleep the body paralyses itself as a protection mechanism in order to prevent the movements which occur in the dream from causing the physical body to move. However, it is possible for this mechanism to be triggered before, during, or after normal sleep while the brain awakens. This can lead to a state where a person is lying in bed and feels paralyzed. Hypnagogic hallucination may occur in this state, especially auditory ones. Effects of sleep paralysis include heaviness or inability to move the muscles, rushing or pulsating noises, and brief hypnogogic imagery. Experiencing sleep paralysis is a necessary part of WILD, in which dreamers essentially detach their "dream" body from the paralyzed one. Also see OBE or Out-Of-Body-Experience, opposing the scientific theory of these occurrences stating that the paralysis is actually an occurrence to one who is already "separated" from their physical body meaning that "physical action potentials" have no effect here but "mental actions" do - a hint given that those who are finding difficulty moving are using the wrong "mechanism".

Out-of-body experience

An out-of-body experience (OBE or sometimes OOBE) is an experience that typically involves a sensation of floating outside of one's body and, in some cases, perceiving one's physical body from a place outside one's body (autoscopy). About one in ten people think they have had an out-of-body experience at some time in their lives. Scientists are learning about the phenomenon.

OBEs induced from waking (with the intention of achieving Astral Projection) and lucid dreams induced from waking cover such similar ground that common misinterpretation of one as the other (or even equivalence) can be hypothesized Realistic-seeming yet physically impossible impressions of flying, time-traveling or walking through the walls of an environment matching one's bedroom are equally hallmarks of either. (As those who have experienced them will attest, neither "feels" like ordinary dreams at all.) Their induction techniques are similar, and both are easier to perform at times typical for afternoon naps and late morning REM cycles.


During most dreams, sleepers are not aware that they are dreaming. The reason for this has not been determined, and does not appear to have an obvious answer. There have been attempts by various fields of psychology to provide an explanation. For example, some proponents of Depth psychology suggest that mental processes inhibit the critical evaluation of reality within dreams.

Physiology suggests that “seeing is believing” to the brain during any mental state. This being said, if the brain perceives something with great clarity or intensity, it will believe that it is real. Even waking consciousness is liable to accept discontinuous or illogical experience as real if presented as such to the brain. Dream consciousness is similar to that of a hallucinating awake subject.

Dream or hallucinatory images triggered by the brain stem are considered to be real, even if fantastic. The impulse to accept the evident is so strong the dreamer will often invent a memory or story to cover up an incongruous or unrealistic event in the dream. “That man has two heads!” is usually followed not with “I must be dreaming!” but with “Yes, I read in the paper about these famous Siamese twins.” Or other times there will be an explanation that, in the dream, makes sense and seems very logical, but when the dreamer awakes, he/she will realize that it is rather far fetched or even complete gibberish.

Developmental psychology suggests that the dream world is not bizarre at all when viewed developmentally, since we were dreaming as children before we learned all of the physical and social laws that train the mind to a “reality.” Fluid imaginative constructions may have preceded the more rigid, logical waking rules and continue on as a normative lifeworld alongside the acquired, waking life world. Dreaming and waking consciousness differ only in their respective level of expectations, the waking “I” expecting a stricter set of “reality rules” as the child matures. The experience of “waking up” normally establishes the boundary between the two lifeworlds and cues the consciousness to adapt to waking “I” expectations. At times, however, this cue is false—a false awakening. Here the waking “I” (with its level of expectations) is activated even though the experience is still hallucinatory. Incongruous images or illogical events during this type of dream can result in lucidity as the dream is being judged by waking “standards.”

Another theory presented by transpersonal psychology and some Eastern religions is that it is the individual's state of consciousness (or awareness) that determines their ability to discriminate and differentiate between what is real, and what is false or illusory. In the dream state, many experiences are accepted as real by the dreamer that would not be accepted as real in the waking state. Some religions such as Buddhism and Hinduism describe states of consciousness (i.e., Nirvana or Moksha) where individuals "wake up", and discover a new or altered state of consciousness that reveals their normal waking experience to be unreal, dream-like, or maya (illusion). The assumption is that there are degrees of wakefulness or awareness, and that both lucid dreaming and normal waking experience lie somewhere towards the middle of this continuum (or hierarchy) of awareness. In this context, there must therefore be states of wakefulness that are superior to normal waking awareness. Just as when the dreamer awakens to realize that a nightmare was illusory, the individual can, like the Buddha, undergo a spiritual awakening and realize that what is called normal waking awareness is, in fact, a dream.

It has been hypothesized that Meditation before sleep can also improve the occurrence of a lucid dream as it potentially minimizes the time taken for a person to fall asleep therefore increasing the chances of maintaining awareness to induce a lucid dream.

Source: Wikipedia.org


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