out-of-body experience out-of-body experience an out-of-body experience (obe or sometimes oobe) is a phenomenon in which a person perceives the world from a location outside their physical body. an obe is a form of autoscopy (literally "seeing self"), although this term is more commonly used to refer to the pathological condition of seeing a second self, or doppelgänger. artist's depiction of the separation stage of an out-of-body experience, which often precedes free movement the term out-of-body experience was introduced in 1943 by g. n. m. tyrrell in his book apparitions, and was adopted by researchers such as celia green, and robert monroe, as an alternative to belief-centric labels such as "astral projection" or "spirit walking". obes can be induced by traumatic brain injuries, sensory deprivation, near-death experiences, dissociative and psychedelic drugs, dehydration, sleep disorders, dreaming, and electrical stimulation of the brain, among other causes. it can also be deliberately induced by some. one in ten people has an obe once, or more commonly, several times in their life. psychologists and neuroscientists regard obes as dissociative experiences occurring along different psychological and neurological factors. spontaneous obes during/near sleep main article: sleep paralysis those experiencing obes sometimes report (among other types of immediate and spontaneous experience) a preceding and initiating lucid-dream state. in many cases, people who claim to have had an obe report being on the verge of sleep, or being already asleep shortly before the experience. a large percentage of these cases refer to situations where the sleep was not particularly deep (due to illness, noises in other rooms, emotional stress, exhaustion from overworking, frequent re-awakening, etc.). in most of these cases subjects perceive themselves as being awake; about half of them note a feeling of sleep paralysis. near-death experiences another form of spontaneous obe is the near-death experience (nde). some subjects report having had an obe at times of severe physical trauma such as near-drownings or major surgery. near-death experiences may include subjective impressions of being outside the physical body, sometimes visions of deceased relatives and religious figures, and transcendence of ego and spatiotemporal boundaries. the experience typically includes such factors as: a sense of being dead; a feeling of peace and painlessness; hearing of various non-physical sounds, an out-of-body experience; a tunnel experience (the sense of moving up or through a narrow passageway); encountering "beings of light" and a god-like figure or similar entities; being given a "life review", and a reluctance to return to life. resulting from extreme physical effort along the same lines as an nde, extreme physical effort during activities such as high-altitude climbing and marathon running can induce obes. a sense of bilocation may be experienced, with both ground and air-based perspectives being experienced simultaneously. induced obes chemical obes can be induced by hallucinogens (particularly dissociatives) such as psilocybin, ketamine, dmt, mda, and lsd. mental induction falling asleep physically without losing awareness. the "mind awake, body asleep" state is widely suggested as a cause of obes, voluntary and otherwise. thomas edison used this state to tackle problems while working on his inventions. he would rest a silver dollar on his head while sitting with a metal bucket in a chair. as he drifted off, the coin would noisily fall into the bucket, restoring some of his alertness. obe pioneer sylvan muldoon more simply used a forearm held perpendicular in bed as the falling object. salvador dalí was said to use a similar "paranoiac-critical" method to gain odd visions which inspired his paintings. deliberately teetering between awake and asleep states is known to cause spontaneous trance episodes at the onset of sleep which are ultimately helpful when attempting to induce an obe. by moving deeper and deeper into relaxation, one eventually encounters a "slipping" feeling if the mind is still alert. this slipping is reported to feel like leaving the physical body. some consider progressive muscle relaxation as an active form of sensory deprivation. deep trance, meditation and visualization. the types of visualizations vary; some common analogies include climbing a rope to "pull out" of one's body, floating out of one's body, getting shot out of a cannon, and other similar approaches. this technique is considered hard to use for people who cannot properly relax. one example of such a technique is the popular golden dawn "body of light" technique. mechanical induction brainwave synchronization via audio/visual stimulation. binaural beats can be used to induce specific brainwave frequencies, notably those predominant in various mind awake/body asleep states. binaural induction of a "body asleep" 4 hertz brainwave frequency was observed as effective by the monroe institute, and some authors consider binaural beats to be significantly supportive of obe initiation when used in conjunction with other techniques. simultaneous introduction of "mind awake" beta frequencies (detectable in the brains of normal, relaxed awakened individuals) was also observed as constructive. another popular technology uses sinusoidal wave pulses to achieve similar results, and the drumming accompanying native american religious ceremonies is also believed to have heightened receptivity to "other worlds" through brainwave entrainment mechanisms. direct stimulation of the vestibular cortex. electrical stimulation of the brain, particularly the temporoparietal junction (see blanke study below). sensory deprivation. this approach aims to induce intense disorientation by removal of space and time references. flotation tanks or pink noise played through headphones are often employed for this purpose. sensory overload, the opposite of sensory deprivation. the subject can for instance be rocked for a long time in a specially designed cradle, or submitted to light forms of torture, to cause the brain to shut itself off from all sensory input. both conditions tend to cause confusion and this disorientation often permits the subject to experience vivid, ethereal out-of-body experiences. strong g-forces that causes blood to drain from parts of the brain, as experienced for example in high-performance aircraft or high-g training for pilots and astronauts. an apparatus that uses a head-mounted display and a touch that confuses the sense of proprioception (and which can also create the sensation of additional limbs). obe theories psychological in the fields of cognitive science and psychology obes are considered dissociative experiences arising from different psychological and neurological factors. scientists consider the obe to be an experience from a mental state, like a dream or an altered state of consciousness without recourse to the paranormal. charles richet (1887) held that obes are created by the subject's memory and imagination processes and are no different from dreams. james h. hyslop (1912) wrote that obes occur when the activity of the subconscious mind dramatizes certain images to give the impression the subject is in a different physical location. eugéne osty (1930) considered obes to be nothing more than the product of imagination. other early researchers (such as schmeing, 1938) supported psychophysiological theories. g. n. m. tyrrell interpreted obes as hallucinatory constructs relating to subconscious levels of personality. donovan rawcliffe (1959) connected the obe experience with psychosis and hysteria. other researchers have discussed the phenomena of the obe in terms of a distortion of the body image (horowitz, 1970) and depersonalization (whitlock, 1978). the psychologists nandor fodor (1959) and jan ehrenwald (1974) proposed that an obe is a defense mechanism designed to deal with the threat of death. according to (irin and watt, 2007) jan ehrenwald had described the out-of-body experience (obe) "as an imaginal confirmation of the quest for immortality, a delusory attempt to assure ourselves that we possess a soul that exists independently of the physical body". the psychologists donald hebb (1960) and cyril burt (1968) wrote on the psychological interpretation of the obe involving body image and visual imagery. graham reed (1974) suggested that the obe is a stress reaction to a painful situation, such as the loss of love. john palmer (1978) wrote that the obe is a response to a body image change causing a threat to personal identity. carl sagan (1977) and barbara honegger (1983) wrote that the obe experience may be based on a rebirth fantasy or reliving of the birth process based on reports of tunnel-like passageways and a cord-like connection by some obers which they compared to an umbilical cord. susan blackmore (1978) came to the conclusion that the obe is a hallucinatory fantasy as it has the characteristics of imaginary perceptions, perceptual distortions and fantasy-like perceptions of the self (such as having no body). ronald siegel (1980) also wrote that obes are hallucinatory fantasies. harvey irwin (1985) presented a theory of the obe involving attentional cognitive processes and somatic sensory activity. his theory involved a cognitive personality construct known as psychological absorption and gave instances of the classification of an obe as examples of autoscopy, depersonalization and mental dissociation. the psychophysiologist stephen laberge (1985) has written that the explanation for obes can be found in lucid dreaming. david hufford (1989) linked the obe experience with a phenomenon he described as a nightmare waking experience, a type of sleep paralysis. other scientists have also linked obes to cases of hypnagogia and sleep paralysis (cataplexy). in case studies fantasy proneness has been shown to be higher among obers than those who have not had an obe. the data has shown a link between the obe experience in some cases to fantasy prone personality (fpp). in a case study involving 167 participants the findings revealed that those who claimed to have experienced the obe were "more fantasy prone, higher in their belief in the paranormal and displayed greater somatoform dissociation." research from studies has also suggested that obes are related to cognitive-perceptual schizotypy. terence hines (2003) has written that spontaneous out-of-body experiences can be generated by artificial stimulation of the brain and this strongly suggests that the obe experience is caused from "temporary, minor brain malfunctions, not by the person's spirit (or whatever) actually leaving the body." in a study review of neurological and neurocognitive data (bünning and blanke, 2005) wrote that obes are due to "functional disintegration of lower-level multisensory processing and abnormal higher-level self-processing at the temporoparietal junction." some scientists suspect that obes are the result of a mismatch between visual and tactile signals. richard wiseman (2011) has noted that obe research has focused on finding a psychological explanation and "out-of-body experiences are not paranormal and do not provide evidence for the soul. instead, they reveal something far more remarkable about the everyday workings of your brain and body." a study conducted by jason braithwaite and colleagues (2011) linked the obe to "neural instabilities in the brain's temporal lobes and to errors in the body's sense of itself". braithwaite et al. (2013) reported that the "current and dominant view is that the obe occurs due to a temporary disruption in multi-sensory integration processes." paranormal writers in the fields of parapsychology and occultism have written that obes are not psychological and that a soul, spirit or subtle body can detach itself out of the body and visit distant locations. out-of-the-body experiences were known during the victorian period in spiritualist literature as "travelling clairvoyance". in old indian scriptures, such a state of consciousness is also referred to as turiya, which can be achieved by deep yogic and meditative activities, during which a yogi may be liberated from the duality of mind and body, allowing them to intentionally leave the body and then return to it. the body carrying out this journey is called "vigyan dehi" ("scientific body"). the psychical researcher frederic myers referred to the obe as a "psychical excursion". an early study that described alleged cases of obe was the two-volume phantasms of the living, published in 1886 by the psychical researchers edmund gurney, myers, and frank podmore. the book was largely criticized by the scientific community because the anecdotal reports in almost every case lacked evidential substantiation. a 19th-century illustration of robert blair's poem the grave, depicting the soul leaving the body the theosophist arthur powell (1927) was an early author to advocate the subtle body theory of obes. sylvan muldoon (1936) embraced the concept of an etheric body to explain the obe experience. the psychical researcher ernesto bozzano (1938) had also supported a similar view describing the phenomena of the obe experience in terms of bilocation in which an "etheric body" can release itself from the physical body in rare circumstances. the subtle body theory was also supported by occult writers such as ralph shirley (1938), benjamin walker (1977), and douglas baker