An out-of-body experience (OBE or sometimes OOBE) is an experience that typically involves a sensation of floating outside one's body and, in some cases, perceiving one's physical body from a place outside one's body (autoscopy).
The term out-of-body experience was introduced in 1943 by George 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", "soul travel", or "spirit walking". OBEs can be induced by brain traumas, sensory deprivation, near-death experiences, dissociative and psychedelic drugs, dehydration, sleep, and electrical stimulation of the brain, among others. It can also be deliberately induced by some.
Science currently considers the OBE a type of hallucination that can be caused by various psychological and neurological factors. Some parapsychologists and occult writers treat OBEs as evidence that a soul, spirit or subtle body can detach itself from the body and visit distant locations. One in ten people have an OBE once, or more commonly, several times in their life, but scientists still know little about the phenomenon.
- 1 Spontaneous
- 2 Phenomenology
- 3 Theories of OBEs
- 4 Studies of OBEs
- 5 Astral projection
- 6 See also
- 7 Notes
- 8 References
- 9 Further reading
- 10 External links
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 the subjects then feel themselves awake; about half of them noted a feeling of sleep paralysis.
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.
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 apparent, with both ground and air-based perspectives being experienced simultaneously.
Consciously controlled and pre-meditated OBE methods (examples of which are widely available in many popular books on the subject) are also reported. Some people have attempted to develop techniques to induce OBEs.
- Falling asleep physically without losing wakefulness. 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 relaxation a passive form of sensory deprivation.
- Waking up mentally but not physically. This related technique is typically achieved through the practice of lucid dreaming. Once inside a lucid dream, the dreamer either shifts the subject matter of the dream in an OBE direction or banishes the dream imagery completely, in doing so gaining access to the underlying state of sleep paralysis ideal for visualization of separation from the body.
- Deep trance, meditation and visualization. The types of visualizations vary; some common imageries used 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.
- 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.
- Magnetic stimulation of the brain, as with the God helmet developed by Michael Persinger.
- 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 encourage 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.
- OBEs induced with drugs are sometimes considered to be hallucinations (i.e., purely subjective), even by those who believe the phenomenon to be objective in general. There are several types of drugs that can initiate an OBE, primarily the dissociative hallucinogens such as ketamine, dextromethorphan (DM or DXM), and phencyclidine (PCP). It has also been reported under the influence of tryptamine psychedelics including dimethyltryptamine (DMT) from ayahuasca. Salvia divinorum has been known to produce symptoms in which the user is said to be able to leave his or her body and travel to many places at once. Many users also claim that they feel as if their "soul" falls out of their body.
- Methamphetamine has also been known to cause OBEs, not in itself but through lack of sleep. It has been reported that it felt like the person was talking above and behind them and, being under the influence of the drug, had no idea what was happening.
- Galantamine is a nootropic that can increase the odds of success when using along with out-of-body experience or lucid dream induction techniques.
Perceptions of environment
OBEs tend to fall into two types, categorized by Robert Monroe as Locale 1 and Locale 2 experiences.
In Locale 1 experiences the environment is largely consistent with reality; other common labels for this form are etheric, ethereal or RTZ (Real Time Zone) projections. The onset of this type can be frightening as intense physiological sensations may be perceived, such as electrical tingling, full body vibrations and racing heartbeat. Confusion is common in spontaneous Locale 1 experiences; the person can believe he or she has awakened (or died) physically and panic can be caused by the realization that one's limbs appear to be penetrating other objects.
Locale 2 experiences are less overtly physical in nature and have much subjective overlap with lucid dreaming. The subject is immersed in unrealistic worlds, modified forms of reality exhibiting physically impossible or inconsistent features. Bright and vivid colors are a common feature of this form. Robert Bruce considers this type of OBE to be an astral projection.
Some who experience OBEs claim to have willed themselves out of their bodies, while others report having found themselves being pulled from their bodies, usually following a feeling of paralysis.
- Withdrawal stage: Conscious interaction with the physical environment ceases. Attention is elsewhere, with sensory inputs going unnoticed; the body is on auto-pilot. Sleeping is an example of this stage.
- Cataleptic stage: Movement is totally impaired. Alternative sensory information may suddenly seem present, such as intense vibrations, noises and sight through closed eyelids.
- Separation stage: With effort, the perceptual viewpoint can be pulled away from the physical body location. Still subject to intense sensation, pull back towards the body obstructs progression.
- Free movement stage: Beyond a certain radius, movement becomes unimpeded, with control increasing markedly. Visual and mental clarity can vary greatly, from barely functional to exceptional.
- Re-entry stage: Perceived need to return increases, leading either to voluntary reversal of separation or extremely fast involuntary snap-back. Alternatively, a transition to waking or sleeping may occur.
In practice, the absence of one or more of the classical stages is not unusual. Some (notably Robert Monroe) have claimed these stages become considerably less applicable with extreme familiarity with OBE, eventually finding just a deliberate mental shift to the feeling of the state equivalent. Monroe likened this to tuning a radio away from one station to another into a different focus level of attention.
The phenomenology of an NDE usually includes additional physiological, psychological and transcendental factors beyond those of typical OBEs (Parnia, Waller, Yeates & Fenwick, 2001). Near-death experiences may include subjective impressions of being outside the physical body, visions of deceased relatives and religious figures, and transcendence of ego and spatiotemporal boundaries. Typically the experience 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 people of Light; God-like figures, helpers, spiritual guides, or similar forces; being given a "Life review", and a reluctance to return to life.
Theories of OBEs
The accepted explanation for the OBE in the fields of cognitive science and psychology is that the OBE is a hallucinatory construct that arises from different psychological factors. The scientific community 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.
An early researcher Edmund Gurney (1886) proposed that out-body-body experiences were hallucinations of the pathological type. Charles Richet (1887) held that OBEs are created by the subject's memory and imagination processes and are no different from dreams. James 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. Eugèn 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 question 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 they have characteristics based around 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.
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 temporo-parietal junction." Some scientists suspect that OBEs are the result of a mismatch between visual and tactile signals.
Writers within 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.
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 (1979).
James Baker (1954) wrote that a mental body enters an "intercosmic region" during the OBE. Some non-occult writers such as Robert Crookall in many publications supported the subtle body theory of OBEs. Gastone De Boni (1960) and other writers such as Hornell Hart (1967) also speculated on the existence of a subtle body to explain the OBE experience.
The paranormal approach to OBEs has not been supported by all researchers within the study of parapsychology. Gardner Murphy (1961) wrote OBEs are "not very far from the known terrain of general psychology, which we are beginning to understand more and more without recourse to the paranormal". Susan Blackmore (1982) criticised the subtle body interpretation. The parapsychologist Carlos Alvarado (1989) wrote that the subtle body theory of the OBE is considered obsolete by the scientific community due to research supporting the psychological approach since the 1970s.
Robert Bruce (1999) endorsed a theory of subtle bodies entering nonphysical dimensions to explain OBEs. In 2011, the paranormal author Anthony Peake set forth his intrasomatic model of out of body and near death experience. Peake claimed that consciousness did not leave the body during these experiences, but rather traveled inward into the recesses of the brain's structure.
Studies of OBEs
The first extensive scientific study of OBEs was made by Celia Green (1968). She collected written, first-hand accounts from a total of 400 subjects, recruited by means of appeals in the mainstream media, and followed up by questionnaires. Her purpose was to provide a taxonomy of the different types of OBE, viewed simply as an anomalous perceptual experience or hallucination, while leaving open the question of whether some of the cases might incorporate information derived by extrasensory perception.
Previous collections of cases had been made by Dr. Ernesto Bozzano (Italy) and Dr. Robert Crookall (UK). Crookall approached the subject from a spiritualistic position, and collected his cases predominantly from spiritualist newspapers such as the Psychic News, which appears to have biased his results in various ways. For example, the majority of his subjects reported seeing a cord connecting the physical body and its observing counterpart; whereas Green found that less than 4% of her subjects noticed anything of this sort, and some 80% reported feeling they were a "disembodied consciousness", with no external body at all.
In 1981, Brazilian Physician and medium Waldo Vieira proposed a new field in parapsychology called projectiology, in which researchers study the subjective dynamics of the OBE directly through systematic self-experimentation rather than through verbal reports. He also formed an institution called the CCC - Center of Continued Consciousness (later IIPC - International Institute of Conscientiology), to promote discussions about the subject.
In 1999, at the 1st International Forum of Consciousness Research in Barcelona, International Academy of Consciousness research-practitioners Wagner Alegretti and Nanci Trivellato presented preliminary findings of an online survey on the out-of-body experience answered by internet users interested in the subject; therefore, not a sample representative of the general population.
1,007 (85%) of the first 1,185 respondents reported having had an OBE. 37% claimed to have had between two and ten OBEs. 5.5% claimed more than 100 such experiences. 45% of those who reported an OBE said they successfully induced at least one OBE by using a specific technique. 62% of participants claiming to have had an OBE also reported having enjoyed nonphysical flight; 40% reported experiencing the phenomenon of self-bilocation (i.e. seeing one's own physical body whilst outside the body); and 38% claimed having experienced self-permeability (passing through physical objects such as walls). The most commonly reported sensations experienced in connection with the OBE were falling, floating, repercussions e.g. myoclonia (the jerking of limbs, jerking awake), sinking, torpidity (numbness), intracranial sounds, tingling, clairvoyance, oscillation and serenity.
Another reported common sensation related to OBE was temporary or projective catalepsy, a more common feature of sleep paralysis. The sleep paralysis and OBE correlation was later corroborated by the Out-of-Body Experience and Arousal study published in Neurology  by Kevin Nelson et al. (2007). Also noteworthy, is the Waterloo Unusual Sleep Experiences Questionnaire  that further illustrates the correlation.
William Buhlman, an author on the subject, has conducted an informal but informative online survey  as well.
Neurology and OBE-like experiences
There are several possible physiological explanations for parts of the OBE. OBE-like experiences have been induced by stimulation of the brain. OBE-like experience has also been induced through stimulation of the posterior part of the right superior temporal gyrus in a patient. Positron-emission tomography was also used in this study to identify brain regions affected by this stimulation. The term OBE-like is used above because the experiences described in these experiments either lacked some of the clarity or details of normal OBEs, or were described by subjects who had never experienced an OBE before. Such subjects were therefore not qualified to make claims about the authenticity of the experimentally-induced OBE.
English psychologist Susan Blackmore and others suggest that an OBE begins when a person loses contact with sensory input from the body while remaining conscious. The person retains the illusion of having a body, but that perception is no longer derived from the senses. The perceived world may resemble the world he or she generally inhabits while awake, but this perception does not come from the senses either. The vivid body and world is made by our brain's ability to create fully convincing realms, even in the absence of sensory information. This process is witnessed by each of us every night in our dreams, though OBEs are claimed to be far more vivid than even a lucid dream.
Irwin pointed out that OBEs appear to occur under conditions of either very high or very low arousal. For example, Green found that three quarters of a group of 176 subjects reporting a single OBE were lying down at the time of the experience, and of these 12% considered they had been asleep when it started. By contrast, a substantial minority of her cases occurred under conditions of maximum arousal, such as a rock-climbing fall, a traffic accident, or childbirth. McCreery has suggested that this paradox may be explained by reference to the fact that sleep can supervene as a reaction to extreme stress or hyper-arousal. He proposes that OBEs under both conditions, relaxation and hyper-arousal, represent a form of "waking dream", or the intrusion of Stage 1 sleep processes into waking consciousness.
Olaf Blanke studies
Research by Olaf Blanke in Switzerland found that it is possible to reliably elicit experiences somewhat similar to the OBE by stimulating regions of the brain called the right temporal-parietal junction (TPJ; a region where the temporal lobe and parietal lobe of the brain come together). Blanke and his collaborators in Switzerland have explored the neural basis of OBEs by showing that they are reliably associated with lesions in the right TPJ region and that they can be reliably elicited with electrical stimulation of this region in a patient with epilepsy. These elicited experiences may include perceptions of transformations of the patient's arms and legs (complex somatosensory responses) and whole-body displacements (vestibular responses).
In neurologically normal subjects, Blanke and colleagues then showed that the conscious experience of the self and body being in the same location depends on multisensory integration in the TPJ. Using event-related potentials, Blanke and colleagues showed the selective activation of the TPJ 330–400 ms after stimulus onset when healthy volunteers imagined themselves in the position and visual perspective that generally are reported by people experiencing spontaneous OBEs. Transcranial magnetic stimulation in the same subjects impaired mental transformation of the participant's own body. No such effects were found with stimulation of another site or for imagined spatial transformations of external objects, suggesting the selective implication of the TPJ in mental imagery of one's own body.
In a follow up study, Arzy et al. showed that the location and timing of brain activation depended on whether mental imagery is performed with mentally embodied or disembodied self location. When subjects performed mental imagery with an embodied location, there was increased activation of a region called the "extrastriate body area" (EBA), but when subjects performed mental imagery with a disembodied location, as reported in OBEs, there was increased activation in the region of the TPJ. This leads Arzy et al. to argue that "these data show that distributed brain activity at the EBA and TPJ as well as their timing are crucial for the coding of the self as embodied and as spatially situated within the human body."
Blanke and colleagues thus propose that the right temporal-parietal junction is important for the sense of spatial location of the self, and that when these normal processes go awry, an OBE arises.
In August 2007 Blanke's lab published research in Science demonstrating that conflicting visual-somatosensory input in virtual reality could disrupt the spatial unity between the self and the body. During multisensory conflict, participants felt as if a virtual body seen in front of them was their own body and mislocalized themselves toward the virtual body, to a position outside their bodily borders. This indicates that spatial unity and bodily self-consciousness can be studied experimentally and is based on multisensory and cognitive processing of bodily information.
Michael Persinger studies
Michael Persinger has undertaken similar research to Olaf Blanke using magnetic stimulation applied to the right temporal lobe of the brain, which is known to be involved in visuo-spatial functions, multi-sensory integration and the construction of the sense of the body in space. Persinger's research also found evidence for objective neural differences between periods of remote viewing in two individuals thought to have psychic abilities. Persinger undertook his research on Sean Harribance and Ingo Swann, a renowned remote viewer who has taken part in numerous studies. Examination of Harribance showed enhanced EEG activity within the alpha band (8–12 Hz) over Harribance's right parieto-occipital region, consistent with neuropsychological evidence of early brain trauma in these regions. In a second study, Ingo Swann was asked to draw images of pictures hidden in envelopes in another room. Individuals with no knowledge of the nature of the study rated Swann's comments and drawings as congruent with the remotely viewed stimulus at better than chance levels. Additionally, on trials in which Swann was correct, the duration of 7 Hz (alpha band) paroxysmal discharges over the right occipital lobe was longer. Subsequent anatomical MRI examination showed anomalous subcortical white matter signals focused in the perieto-occipital interface of the right hemisphere that were not expected for his age or history.
In August 2007, Henrik Ehrsson, then at the Institute of Neurology at University College of London (now at the Karolinska Institute in Sweden), published research in Science demonstrating the first experimental method that, according to the scientist's claims in the publication, induced an out-of-body experience in healthy participants. The experiment was conducted in the following way:
The study participant sits in a chair wearing a pair of head-mounted video displays. These have two small screens over each eye, which show a live film recorded by two video cameras placed beside each other two metres behind the participant's head. The image from the left video camera is presented on the left-eye display and the image from the right camera on the right-eye display. The participant sees these as one "stereoscopic" (3D) image, so they see their own back displayed from the perspective of someone sitting behind them.
The researcher then stands just beside the participant (in their view) and uses two plastic rods to simultaneously touch the participant's actual chest out-of-view and the chest of the illusory body, moving this second rod towards where the illusory chest would be located, just below the camera's view.
Both critics and the experimenter himself note that the study fell short of replicating "full-blown" OBEs. As with previous experiments which induced sensations of floating outside of the body, Ehrsson's work does not explain how a brain malfunction might cause an OBE. Essentially, Ehrsson created an illusion that fits a definition of an OBE in which "a person who is awake sees his or her body from a location outside the physical body."
University of Southampton study
In the autumn of 2008, 25 UK and US hospitals began participation in a 3-year study, coordinated by Dr. Sam Parnia and Southampton University. Following on from the work of Pim van Lommel in the Netherlands, the study aims to examine near-death experiences in 1,500 cardiac arrest survivors and so determine whether people without a heartbeat or brain activity can have documentable out-of-body experiences.
Smith & Messier
A recent functional imaging study reported the case of a woman who could experience out of body experience at will. She reported developing the ability as a child and associated it with difficulties in falling sleep. Her OBEs continued into adulthood but became less frequent. She was able to see herself rotating in the air above her body, lying flat, and rolling in the horizontal plane. She reported sometimes watching herself move from above but remained aware of her unmoving “real” body. The participant reported no particular emotions linked to the experience. "[T]he brain functional changes associated with the reported extra-corporeal experience (ECE) were different than those observed in motor imagery. Activations were mainly left-sided and involved the left supplementary motor area and supramarginal and posterior superior temporal gyri, the last two overlapping with the temporal parietal junction that has been associated with out-of-body experiences. The cerebellum also showed activation that is consistent with the participant’s report of the impression of movement during the ECE. There was also left middle and superior orbital frontal gyri activity, regions often associated with action monitoring." 
OBE training and research facilities
The Monroe Institute's Nancy Penn Center is the oldest and most established facility specializing in out-of-body experience induction. The Center for Higher Studies of the Consciousness in Brazil is another large OBE training facility. The International Academy of Consciousness in southern Portugal features the Projectarium, a spherical structure dedicated exclusively for practice and research on out-of-body experience.
Olaf Blanke's Laboratory of Cognitive Neuroscience has become a well-known laboratory for OBE research.
Astral projection is a paranormal interpretation of out-of-body experiences that assumes the existence of one or more non-physical planes of existence and an associated body beyond the physical. Commonly such planes are called astral, etheric, or spiritual. Astral projection is often experienced as the spirit or astral body leaving the physical body to travel in the spirit world or astral plane.
Evidence for objective reality of projection on to the etheric plane (a near-copy of the physical plane) is sometimes suggested when people, such as patients during surgery, describe OBEs in which they see or hear events or objects outside their sensory range (for instance, Pam Reynolds reported experiencing an OBE during brain surgery and described a surgical instrument she had not seen previously, as well as conversation that occurred while she was under anesthesia).
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