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Providing a scientific explanation for the phenomenon of near-death experience has been a difficult challenge for scientists ever since data in the form of NDE testimonials started appearing in the mid 1970s. Some of the scientific arguments against the validity of NDEs (i.e., that they are only hallucinations) are also applicable to out-of-body experiences in general since out-of-body experiences are an important component of most NDEs.
When examining the Near-death experience, we might first ask the question, "Why did the NDE concept emerge when it did?"
One explanation is that prior to the 1970s, ambulances were little more than transport services whose personnel had little knowledge of emergency medicine. The result of this was that most serious injuries resulted in the death of patients before they reached the hospital or shortly thereafter. The medical art of resuscitation was in its infancy, and the well known role of the Emergency Medical Technician did not yet exist. Thus, few patients came back to describe their near-death experiences. The large amounts of data necessary to develop the NDE concept probably came into being as a result of improvements in emergency medicine.
As NDEs became better known, psychologists, physiologists, and neurologists began looking for ways to account for NDEs using physical and medical explanations. Reducing complex psychological phenomena to simpler material laws and processes is a primary occupation of scientists. The goal is to explain away the supernatural, and reduce it to physical causes such as brain chemistry (neural noise, hypoxia, etc.), psychological states (wish fulfillment or reliving the birth trauma), and sociological factors (religious fantasies based on social conditioning). The scientist's refusal to accept supernatural explanations for natural phenomena has in general been very advantageous for society, and resulted in many of the advances in material comfort that we see today. Their skepticism is therefore something to be praised and makes a valuable contribution to the world we live in.
However, when it comes to investigating the events and experiences which occur on the borders of life and death, their standard assumptions and methodologies become somewhat problematic. As with scientific attempts to describe the origins and fundamental makeup of matter or how objects behave at or beyond the speed of light, seemingly implausible or contradictory claims lead to questioning the basic premises of science when investigating borderline or liminal areas. Such areas of investigation as Near-death experience or subatomic matter seem to defy the clear explanations and rational analysis that are so fruitful in the other more common domains of scientific inquiry.
Because NDEs contain so many elements, a number of different complementary explanations are needed to account for this complexity. But in most cases, each explanation focuses on only one element of the NDE and ignores the others. Such explanations use the divide and conquer approach to weaken the overall NDE concept by reducing one of its component parts to physical causes.
Here are some common explanations for the elements of NDEs followed by some reasons why these explanations seem implausible or inadequate. The first set of explanations are physiological or medical explanations, and the second set are psychological explanations.
Physiological or Medical Explanations for NDEs
The NDE euphoria is caused by hypoxia (lack of oxygen to the brain)
The NDE euphoria is caused by the of secretion of endorphins (natural analgesic or pain-relieving chemicals secreted by the body during physical trauma)
The NDE tunnel vision is caused by hypoxia (lack of oxygen to the brain)
The "neural noise" concept is another theory which claims to explain the NDE tunnel experience
Psychological Explanations for NDEs
NDEs are religious hallucinations caused by Freudian wish-fulfillment fantasies (Freud thought these infantile longings were the basis for all religious experience)
The NDE's euphoria is based on a birth memory of peace and satisfaction of the fetus in the womb (Romain Rolland believed that euphoric feelings associated with religious experience could be traced to the "oceanic feeling" of the experience of the fetus in the womb. NDEs contain such euphoria and the memory of womb consciousness may be the source of this euphoria).
The "tunnel experience" during NDEs is caused by the re-experience of the birth trauma (the tunnel is the birth canal, the light at the end is the external world, and the doctor is the being of light)
Drugs as an Explanation for NDEs
The web page http://www.skepdic.com/nde.html repeats a common theme that if a drug is capable of producing some of the elements of an NDE, the NDE must be the direct result of changes in brain chemistry caused by the drug. The web page states:
The previous sentence is a very strong statement and is also highly dubious.
For instance, the history of people claiming that they communed or talked with God, beings of light, or non-physical entities is vast and plays a large role in many of the world's religions. Mediums and Shaman have talked to disembodied entities for centuries, and have been an important part of cultures from ancient Greece to Tibet to modern day America (with its interest in such religions as Theosophy, Scientology, and the Spiritualist movements). Many Shamans have used drugs to enhance their vision. Dr. Jansen's claim that he knows that none of the people under the influence of ketamine are talking to such entities has no basis in fact. His belief that such claims are obviously false reveals more about his own presuppositions about the way the world works than it does about what is actually happening with his subjects. Dr. Jansen has softened his claim about the unreality of drug-related experience over the years, but his earlier position is still a popular one in and out of the scientific community.
Note that the above statement does not say that all or even some of these experiences occur to one individual or that those that do occur appear in a prescribed sequence as often happens in an NDE. It only says that at least one of the above experiences can occur to a single individual under the influence of the drug. Ketamine certainly does not cause NDEs to occur though it appears to sometimes cause the dissociation where the mind separates from the body in a way that appears similar to what occurs in many NDEs.
It also does not talk about the content of the hallucinations under ketamine influence. Why is it that during NDEs, such "hallucinations" consist of swimmers seeing themselves drowning. Why do people with allergic reactions in their home or children hit by cars while riding bicycles see themselves flying through space following ambulances to emergency rooms? Why do people in hospitals repeatedly watch themselves being given CPR (See: Near-Death Experience for detained examples)?
The scientific answer to such questions brings us back to the projection of fantasy worlds and social conditioning arguments but, as stated earlier, if the mind is so good at creating hallucinations of accident scenes, hospital rooms, and operating room procedures, why is the same mind so bad at creating hallucinations of God the Father, angels, Saint Peter, Moses, and heaven?
The fact that a specific drug can cause "hallucinations" is not a new or unusual discovery. Therefore, the importance of ketamine research depends on the quality and contents of the hallucinations and their similarity to the NDE experience if they are to help researchers understand near-death experience better.
Without precise statistics, it is difficult to know the contents of the hallucinations of patients under ketamine influence but I suspect that their subject matter does not mimic the complex, detailed, and highly structured kinds of out-of-body experiences of people who have NDEs. Dr. Jansen, so far as I am aware, does not claim that they do this either.
Dr. Jansen does acknowledge some of the limitations in the present research on ketamine:
The primary objection to Dr. Jansen's claim is that a drug capable producing such a wide variety of "side-effects" is probably not the primary cause of such effects but is more likely an ingredient in opening up a huge area of experience which is difficult to classify. The kinds of experience that results from such a drug appear to be more dependent on personality differences of the people taking the drug than on the drug itself. Similarly, trying to reduce the enormous range of LSD experience to simple categories like "psychotomimetic" (imitating psychosis) provides little insight into the effect of the drug because some people become "psychotic" while others remain lucid and rational under LSD influence. One stimulus (a drug such as LSD or ketamine) cannot be accurately said to "cause" dozens (and even hundreds) of different complex psychological effects which vary greatly from individual to individual.
Dr. Jansen's claims are nothing new. LSD experience can produce all the experiences (and a great many more) that are on his list for ketamine. Experimenting with a different drug and repeating similar claims about a range of experience associated with it does not in itself provide new information.
The above quote from skeptic.com is a good illustration of this kind of false reasoning which attempts to account for myriad effects which vary tremendously from individual to individual with a single drug stimulus.
Aldous Huxley's claims that certain drugs open the "doors of perception" thus removing the brain's normal filtering of perception is relevant here. The fact that certain drugs in certain individuals in certain situations permit expanded awareness (or psychotic episodes for that matter) does not mean that they are the primary cause of such awareness or episodes. They may simply remove the barriers to such experience which are normally present.
A similar approach postulates that the human unconscious is opened and made available to the conscious mind by the use of such drugs. Drugs such as ketamine and LSD merely provide access to huge areas of the mind that are normally unconscious rather than mechanically causing illusory perceptions to occur to the individual by altering brain chemistry. Stanislav Grof, the well-known LSD researcher, describes these areas as the "Realms of the Human Unconscious".
The Fundamental Incompatibility - A Tortured Body and an Ecstatic Spirit
The basic quality of consciousness usually described during NDEs is quietness, peacefulness, clarity, happiness, and wonder, accompanied by excellent memory. A crisis of the nervous system should be accompanied by confusion, disorientation, impaired consciousness, and vague or nonexistent memory. The many positive elements described during NDEs should not exist if the brain is in such a degraded state, if NDEs are only a by-product of brain states. Experiences of life-threatening sickness, weakness, shock, and trauma generally have no such positive elements associated with them. Shock or the lack of perfusion of oxygen to the brain is closely associated with a terrible "feeling of impending doom" in the literature. In psychological terms, trauma, danger, and injury may cause the individual to react strongly. These reactions are associated with adrenaline and the "fight or flight" reflex. They ready the individual for dynamic action and movement to increase the probability of survival in dangerous situations. This adrenaline-induced reaction of nervousness and high arousal is also inconsistent with the positive emotions of an NDE.
At bottom, it is quite well known that very sick or injured people do not feel at all well. It might therefore follow that the most profound elements of NDEs are not the result of the sickness or injury but instead arise from a set of causes unrelated to the state of the physical body. NDEs are very positive and joyous even when the physical body and brain are in their very worst condition.
Science and the Necessity of Explaining NDE and OBE Phenomena
The fact that many scientists take many of the explanations listed above seriously seems to indicate that they are in a "holding pattern" waiting for a better explanation to emerge. In the mean time, they feel the need to say something about the NDE phenomena, and the above theories represent their best efforts to date.
One of the most recent media reports on out-of-body experience came from a CNN story where the headline read: "Scientists recreate out-of-body experience". What is actually being done in the experiment if you read further is "creat[ing] the illusion of an out-of-body experience" . This was done with an experiment using two different sets of scenes from different video cameras in association with stereoscopic virtual reality goggles which made the subjects feel like their body was mysteriously shifted to a different location than the one it was in at the beginning of the experiment.
The scientist concluded,
My response is first that reproducing the illusion of an OBE is not necessarily reproducing an OBE. Second, the "feeling" of being outside the body is only one component of an OBE. The perceptions that occur while outside the body which vary greatly are another important component that is not dealt with by this experiment. The idea that there is one kind of feeling associated with being out of the body is naive. This feeling could be described as a simple case of vertigo based on the disorientation of the subjects brought on by the cameras providing them with confusing visual information.
There are also a wide spectrum of internal feelings associated with OBEs. Any researcher who accepts the vague notion of a subject having a single feeling which describes or defines an OBE needs to first sharpen his or her analytic skills before even beginning such an experiment.
Third, only one person in the group of test subjects had ever had an OBE before. So claiming that the feeling is the same is a bit premature on the part of the researchers. We see this tendency to jump to conclusions frequently. Fourth, the interactive side of the OBE where the person moves his or her body and interacts with physical (or nonphysical) objects is completely missing from subjects sitting passively in a chair. This "feeling" of having an OBE seems to differ greatly from many actual OBEs.
The strong desire of scientists to explain out-of-body experience in scientific terms is best illustrated by another report that received world wide interest in and out of the scientific community.
Olaf Blanke, a neurologist at the Geneva University Hospital in Switzerland, made the "discovery" while performing surgery. He stimulated the right angular gyrus, a small region in the brain's right hemisphere, of a women and triggered out-of-body experiences. The patient told doctors, "I see myself lying in bed, from above, but I only see my legs and lower trunk." Subsequent zaps with the electrodes were reported to replicate the effect.
Normally, for a scientific experiment to be worthy of mention, it would require rigorous design and execution followed by a careful analysis of the results. In most cases, it would need to be performed on a number of patients, and a double blind approach would be taken that involved patients who would be given placebo drugs or stimuli. This makes sure the results were not spurious and attributable to something other than the specific intended stimulus of researchers.
In Dr. Blanke's case, we have a situation where one or more doctors interacting with a single patient inadvertently applied a stimulus (stimulation by a electrode to the brain) and "caused" an out-of-body experience. The patient was also prone to "a brain disorder that causes seizures", and therefore not an ideal subject for such an experiment. The credibility of the patient was not questioned, and it appears that an earlier milder stimulus did not cause an OBE but only a change in body image where the body image was distorted in the patient's view (the arm and legs were first shortened and later appeared to be flying up towards the patient's head).
Having read many out-of-body experience descriptions myself, I have never read about one where only half the person's body (the lower half in this case) appeared. The patient's preception seems quite confused and distorted when compared with more common out-of-body experiences where the person sees his or her entire body in an OBE state. The theory also fails to account for the overall environment that is perceived as in the case of an OBE were the body of the person is seen against the backdrop of an operating or hospital room. There seems to be no explanation as to how the angular gyrus portion of the brain is able to construct a three-dimensional birds-eye view of the the surrounding environment which contains the physical body. The brain would be required to somehow contain a holographic model of the room in order to create such a reconstruction and then be able to place the person's body image in the midst of the hologram. The theory would also require the person to be able to move and change the point of view within the hologram as is common in many NDEs and OBEs.
Surprisingly, Dr. Blanke does not feel that he has done enough with his small amount of experimental data by explaining away a huge area of human experience known as out-of-body experience. From the same data, he also purports to explain certain psychic experiences where individuals feel there is a phantom individual shadowing them thus explaining the perception of ghosts and other-worldly entities. He even goes further in speaking about explaining some aspects of schizophrenia where the personality splits into two separate forms of body consciousness that occupy different places in space.
Such claims represent a form of scientific grandiosity, and the credulous media are happy to report that another great mystery has been solved by scientists. Here, we have only this untested hypothesis appearing as the primary subject of articles in scientific journals. The sample size of the experiment (one subject) is far too small to draw any scientifically significant conclusion. The fact that such a haphazard set of events was treated as conclusive science and given so much media and scientific attention seems to show how heavily invested the scientific community is in their reductionist world-view.
Finally, as we can see from Dr. Blanke's and Dr. Ehrsson's experiments, scientists are attempting to account for or explain out-of-body experience by drastically narrowing its scope. The content of this web site should make clear that defining out-of-body experience as people standing outside themselves and looking back at their bodies may be convenient for scientific purposes but it denies or ignores much of the reality of what it is attempting to study. Such narrowing is like studying a pond and claiming to understand the ecology of the ocean. The author would much prefer that such scientists admit they are studying a very simple and limited subset of out-of-body experience and avoid creating confusion inside and outside of the scientific community by drastically over-simplifying the phenomenon of out-of-body experience.
The subtext of all such scientific experiments is that the physical world or our perceptions inside the body are real and any world that results from perceptions outside the body is an illusion or a fake or a construction of the brain (brain state). All scientists have to do is figure out how the brain tricks the individual into believing that something fake is real. Of course all this is an article of faith which is, in principle, not very different from the faith claims made by religious people. What is different is the hope that these scientific assumptions will lead to discoveries that permit prediction and control of the world (and therefore to grant money and the respect of other scientists). In contrast, the supernatural approach surrenders important domains of the universe to mysterious forces that are very difficult to understand and control using scientific forms of inquiry.
However, with these kinds of assumptions, is it any wonder why scientists are not considered objective explorers of the world? They lose their objectivity when they become materialists of the fundamentalist variety who cannot imagine seeing the world outside of this limited, pragmatic, physical frame of reference.
~ Spiritual Travel - Reductionist Arguments Explaining Near death Experiences and OBE's