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 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, more commonly known as 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.

The University of Manchester has conducted yet another OBE survey. The psychologists at U. of Manchester are investigating the idea that out-of-body experiences, commonly thought of as paranormal phenomena, may in fact have their roots in how people perceive and experience their own bodies.

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 suggests 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.

Van Lommel studies

The first clinical study of near-death experiences (NDE's) in cardiac arrest patients was by Pim van Lommel, a cardiologist from the Netherlands, and his team (The Lancet, 2001). Of 344 patients who were successfully resuscitated after suffering cardiac arrest, approximately 18% experienced "classic" NDE's, which included out-of-body experiences. The patients remembered details of their conditions during their cardiac arrest despite being clinically dead with flatlined brain stem activity. Van Lommel concluded that his findings supported the theory that consciousness continued despite lack of neuronal activity in the brain. Van Lommel conjectured that continuity of consciousness may be achievable if the brain acted as a receiver for the information generated by memories and consciousness, which existed independently of the brain, just as radio, television and internet information existed independently of the instruments that received it.

Skeptic Michael Shermer's interpretation of Van Lommel's study, that it demonstrated that the mind was not separate from the brain, has been criticized by Deepak Chopra and also by Jay Ingram of the Canadian Discovery Channel. Ingram commented: "[Shermer's] use of this study to bolster his point is bogus. He could have said, 'The authors think there's a mystery, but I choose to interpret their findings differently'. But he didn't. I find that very disappointing."

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.

Ehrsson study

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.

The participants confirmed that they had experienced sitting behind their physical body and looking at it from that location.

The experiment fits a three-point definition of the out-of-body experience (OBE). The OBE as reported in spontaneous cases can be phenomenologically more complex as commented in Slate and elsewhere.

Dr. Sam Parnia – University of Southampton study

In the fall of 2008, 25 UK and US hospitals began participation in a 3 year study, coordinated by Dr. Sam Parnia and Southampton University. Following on the work of 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.

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

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 anethesia).

Susan Blackmore has disputed whether anything leaves the body during an OBE. If OoBEs are held to the stringent criterion of a laboratory demonstration of some spatial dislocation of mind from brain, experiments have turned up no significant evidence of OoBEs.