 |
|
Scientists propose explanation for out-of-body experiences
August 24, 2007Using virtual reality goggles to mix up the sensory signals reaching the brain, scientists have induced out-of-body-like experiences in healthy people, suggesting a scientific explanation for a phenomenon often thought to be a figment of the imagination.
The sight of their bodies located somewhere else -- thanks to the goggles -- plus the feel of their real bodies being touched simultaneously made volunteers sense that they had moved outside of their physical bodies, according to a pair of studies in the 24 August 2007 issue of the journal Science, published by AAAS, the nonprofit science society.
A disconnect between the brain circuits that process both these types of sensory information may thus be responsible for some out-of-body experiences, the researchers say.
Out-of-body experiences, which generally involve the feeling of disembodiment and seeing one's own body from a location outside the body, can occur in part through drug use, epileptic seizures and other types of brain disturbances.
By projecting a person's awareness into a virtual body, the techniques used in these studies may be useful for training people to do delicate "teleoperating" tasks, such as performing surgeries remotely. The findings may also remove some of the stigma that patients with neurological disorders may feel about having these experiences, which are frequently attributed to an active imagination or some sort of paranormal phenomenon.
The studies also help solve the age-old question of how we perceive our own bodies.
"I'm interested in why we feel that our selves are inside our bodies -- why we have an 'in-body experience,' if you like. This has been discussed for centuries in philosophy, but it's hard to tackle experimentally," said Science Brevium author Henrik Ehrsson of University College London, in London, and the Karolinska Institute in Stockholm.
Both Ehrsson and another research team, led by Olaf Blanke of the Ecole Polytechique Fédérale de Lausanne (EPFL) and the University Hospital in Geneva, Switzerland, used video cameras and virtual reality goggles to show volunteers images of their own bodies from the perspective of someone behind them. The researchers also touched the volunteers' bodies, both physically and virtually.
The volunteers in Ehrsson's study viewed images recorded by the cameras through their headsets. In Blanke and colleagues' study, the video was converted into holograph-like computer simulations.
Ehrsson had the volunteers watch a plastic rod moving toward a location just below the cameras while their real chests were simultaneously touched in the corresponding spot. Questionnaire responses afterwards indicated that the volunteers felt they were located back where the cameras were placed, watching a dummy or a body that belonged to someone else.
"This experiment suggests that the first-person visual perspective is critically important for the in-body experience. In other words, we feel that our self is located where the eyes are," Ehrsson said.
Ehrsson also had the volunteers watch a hammer swing down to a point below the camera, as though it were going to "hurt" an unseen portion of the virtual body. Measurements of skin conductance, which reflects emotional responses such as fear, indicated that the volunteers sensed their "selves" had left their physical bodies and moved to the virtual bodies.
Blanke's team used a similar setup to create out-of-body-like experiences (which they cautioned lacked some aspects of full-blown out-of-body experiences).
After the virtual reality exercise, a researcher would blindfold the volunteers and guide them backward. When the volunteers were asked to return to their original position, they tended to drift toward where they had seen their virtual bodies standing.
Both studies conclude that "multisensory conflict" is a key mechanism underlying out-of-body experiences.
"Brain dysfunctions that interfere with interpreting sensory signals may be responsible for some clinical cases of out-of-body experiences," Ehrsson said. "Though, whether all out-of-body experiences arise from the same causes is still an open question."
Bodily self-consciousness may also involve a cognitive dimension - the ability to distinguish between one's own body and other objects - in addition to sensory signals, Blanke and his coauthors propose.
Supporting this idea, Blanke's team reports that when the volunteers viewed a human-sized block instead of an image of a human body, they successfully returned to their original standing place, indicating that no out-of-body-like illusion had occurred.
"Full-body consciousness seems to require not just the 'bottom up' process of correlating sensory information but also the 'top down' knowledge about human bodies," Blanke said.
Some of the out-of-body experiences that have previously eluded scientific explanation may be related to distorted "full-body perception," according to Blanke. Virtual reality systems may provide further answers.
"We have decades of intense research on visual perception, but not very much yet on body perception. But that may change, now virtual reality offers a way to manipulate full body perception more systematically and probe out-of-body experiences and bodily self consciousness in a new way," Blanke said.
American Association for the Advancement of Science
Out-of-body experiences, which generally involve the feeling of disembodiment and seeing one's own body from a location outside the body, can occur in part through drug use, epileptic seizures and other types of brain disturbances.
By projecting a person's awareness into a virtual body, the techniques used in these studies may be useful for training people to do delicate "teleoperating" tasks, such as performing surgeries remotely. The findings may also remove some of the stigma that patients with neurological disorders may feel about having these experiences, which are frequently attributed to an active imagination or some sort of paranormal phenomenon.
The studies also help solve the age-old question of how we perceive our own bodies.
"I'm interested in why we feel that our selves are inside our bodies -- why we have an 'in-body experience,' if you like. This has been discussed for centuries in philosophy, but it's hard to tackle experimentally," said Science Brevium author Henrik Ehrsson of University College London, in London, and the Karolinska Institute in Stockholm.
Both Ehrsson and another research team, led by Olaf Blanke of the Ecole Polytechique Fédérale de Lausanne (EPFL) and the University Hospital in Geneva, Switzerland, used video cameras and virtual reality goggles to show volunteers images of their own bodies from the perspective of someone behind them. The researchers also touched the volunteers' bodies, both physically and virtually.
The volunteers in Ehrsson's study viewed images recorded by the cameras through their headsets. In Blanke and colleagues' study, the video was converted into holograph-like computer simulations.
Ehrsson had the volunteers watch a plastic rod moving toward a location just below the cameras while their real chests were simultaneously touched in the corresponding spot. Questionnaire responses afterwards indicated that the volunteers felt they were located back where the cameras were placed, watching a dummy or a body that belonged to someone else.
"This experiment suggests that the first-person visual perspective is critically important for the in-body experience. In other words, we feel that our self is located where the eyes are," Ehrsson said.
Ehrsson also had the volunteers watch a hammer swing down to a point below the camera, as though it were going to "hurt" an unseen portion of the virtual body. Measurements of skin conductance, which reflects emotional responses such as fear, indicated that the volunteers sensed their "selves" had left their physical bodies and moved to the virtual bodies.
Blanke's team used a similar setup to create out-of-body-like experiences (which they cautioned lacked some aspects of full-blown out-of-body experiences).
After the virtual reality exercise, a researcher would blindfold the volunteers and guide them backward. When the volunteers were asked to return to their original position, they tended to drift toward where they had seen their virtual bodies standing.
Both studies conclude that "multisensory conflict" is a key mechanism underlying out-of-body experiences.
"Brain dysfunctions that interfere with interpreting sensory signals may be responsible for some clinical cases of out-of-body experiences," Ehrsson said. "Though, whether all out-of-body experiences arise from the same causes is still an open question."
Bodily self-consciousness may also involve a cognitive dimension - the ability to distinguish between one's own body and other objects - in addition to sensory signals, Blanke and his coauthors propose.
Supporting this idea, Blanke's team reports that when the volunteers viewed a human-sized block instead of an image of a human body, they successfully returned to their original standing place, indicating that no out-of-body-like illusion had occurred.
"Full-body consciousness seems to require not just the 'bottom up' process of correlating sensory information but also the 'top down' knowledge about human bodies," Blanke said.
Some of the out-of-body experiences that have previously eluded scientific explanation may be related to distorted "full-body perception," according to Blanke. Virtual reality systems may provide further answers.
"We have decades of intense research on visual perception, but not very much yet on body perception. But that may change, now virtual reality offers a way to manipulate full body perception more systematically and probe out-of-body experiences and bodily self consciousness in a new way," Blanke said.
American Association for the Advancement of Science
The embodied self: Using virtual reality to study the foundations of bodily self-consciousness
A group of neuroscientists and a philosopher have devised a series of novel experiments using virtual reality that could shed light on decades of clinical data pointing to cognitive and perceptual mechanisms involved in humans' concept of self.
Out-of-body experiences may be caused by arousal system disturbances in brain
Having an out-of-body experience may seem far-fetched to some, but for those with arousal system disturbances in their brains, it may not be a far off idea that they could sense they were really outside their own body watching themselves. In previous studies of more than 13,000 Europeans, almost 6 percent said they have had such an out-of-body experience.
Nature press release for 19 September issue
[1] PHYSICS: CERN MAKES ENOUGH ANTIHYDROGEN TO TEST THEORY (DOI: 10.1038/nature01096) ***This paper will be published electronically on Nature`s website on 18 September at 1900 London time / 1400 US Eastern time (which is also when the embargo lifts) as part of the AOP (ahead of print) programme. Although we have included it on this release to avoid multiple mailings it will not appear in print in the September 19 issue, but at a later date.*** Physicists report in Nature online this week that they have made at least 50,000 atoms of antihydrogen, the antimatter counterpart of normal hydrogen atoms. This large quantity of the looking-glass substance should enable them to put to the test one
NEAR-DEATH EXPERIENCE REMAINS A MYSTERY (pp 2010, 2029)
Authors of a Dutch study in this week's issue of THE LANCET conclude that medical explanations cannot account for the phenomonen known as near-death experience (NDE). Only a relatively small proportion of patients who became clinically dead (resulting in oxygen deprivation to the brain) reported NDEs after successful cardiac resuscitation. Some people report a near-death experience (NDE) after a life-threatening crisis. Most previous NDE research has been retrospective and is therefore of limited value. Pim van Lommel and colleagues from Hospital Rijnstate, Arnhem, The Netherlands, aimed to establish the cause of this experience and assess factors that affected its frequency, depth, and cont
More Out-of-body Experience Current Events and Out-of-body Experience News Articles
 | Beyond the Body: An Investigation of Out-Of-The-Body Experiences by Susan J. Blackmore About one person in ten claims to have left his or her body at some time. Some were close to death; others had under-gone an accident or shock. Dr Blackmore's explanation for out-of-body experiences is based on historical and anecdotal material, surveys, and laboratory... |
 | Adventures Beyond the Body: How to Experience Out-of-Body Travel by William Buhlman Explore new worlds . . .If you ever wondered what might lie beyond the reality we experience every day, if you've ever thrilled to accounts of out-of-body travel and longer to go alone for the ride, this fascinating, practical guide is for you. America's leading expert on out-of-body travel tells the riveting story of his travels to other realms and offers easy-to-use techniques to guide you on... |
 | Come to Wisdom's Door: How to Have an Out-of-Body Experience! by Marilynn Hughes OUT-OF-BODY EXPERIENCES/MYSTICISM (POCKET): Ever wanted to have an Out-of-Body Experience? Finally, a comprehensive guide to having an Out-of-Body Experience by someone who has had thousands of them. Never before has the path been laid out in such an easy to understand and implement fashion. Spiritual Seekers . . . this one's for... |
 | Out-of-Body Experiences: How to Have Them and What to Expect by Robert Peterson, Charles Tart Imagine the wonder of leaving your body to travel to places and realms you have only dreamed of. Out of Body Experiences is the book to teach you how to leave your body and what to expect when you do it. A simple step-by-step manual and "flight guide" the author talks not only about his own experiences, but what you may encounter when you leave the body. For the first time, out-of-body... |
 | Astral Dynamics: A New Approach to Out-of-Body Experiences by Robert Bruce, Professor C. E. Lindgren Astral projection is the classic term for what today is more commonly called out-of-body experience or OBE. In this fascinating volume, Robert Bruce has drawn on his lifetime's experience not only traveling in the astral dimension, but teaching others to do so.Astral Dynamics provides, all in one package, a personal narrative, a "how-to," a troubleshooting guide, and a theoretical perspective.... |
 | Mastering Astral Projection: 90-day Guide to Out-of-Body Experience by Robert Bruce, Brian Mercer 2005 Coalition of Visionary Resources (COVR) 2nd Runner Up of Interactive Sideline category! Projecting out-of-body requires a delicate balance of mind, body, and spirit. Mastering Astral Projection offers everyone the opportunity to explore nonphysical dimensions and learn more about their spirituality. This practical guide to achieving conscious out-of-body experiences is based upon... |
 | O.B.E. Out-of-Body Experience by Marquis White Fed up with the world around him Alan searches desperately for a way out of his present circumstances. He's broke, he's lonely and he's tired of the ignorance that plagues society. His blind desperation propels him into a journey beyond any frontier ever reached by man, he travels out of his body! In this new form Alan can do just about anything he wants. He can fly, he can travel at the speed of... |
 | The Secret of the Soul: Using Out-of-Body Experiences to Understand Our True Nature by William L. Buhlman In this remarkable book, William Buhlman, author of the bestselling Adventures Beyond the Body, offers the reader a comprehensive guidebook to understanding and exploring the fascinating phenomenon of out-of-body experiences (OBEs). Learn how you can:Explore your true spiritual self and attain profound transformation in your awareness and knowledge of the universe.Gain life-changing benefits as... |
 | Astral Projection And the Nature of Reality: Exploring the Out-of-body State by John Magnus For nearly a decade, Hampton Roads has been at the forefront of publishing books on the out-of-body exploration of the astral world. Following in that tradition comes Astral Projection and the Nature of Reality, a work that goes farther than ever before in explaining the dimensions to which the out-of-body adventurer can go. Magnus provides a brief history of astral projection and then guides the... |
 | Remote Perceptions: Out-of-Body Experiences, Remote Viewing, and Other Normal Abilities by Angela Thompson Smith As a child, the author believed that everyone shared her psychic abilities. As an adult, she realized that her abilities were special, and became first a participant in and later a researcher of psychic functioning. In Remote Perceptions, she explores past, remote viewing, out-of-body experiences (OBEs), the psychic spying of international intelligence agencies, and the possible future of psychic... |
| © 2009 BrightSurf.com |