總網頁瀏覽量

2010年9月25日 星期六

Near Death Experiences (NDE's)

The question of whether we have a soul is a question of the first importance for all Christians. If we do not have a soul which survives after death and which will be rejoined to another "body" upon the eschatological event called the Resurrection of the Body, an article of faith which all Catholics will have to recite as part of the Credo in the Sunday mass, then an extremely important foundation of his faith will be gone. In the papal encyclical called Humanis Generis (Concerning the Human Genus), Pope Pius XII declared: "That souls are immediately created by God is a view which the Catholic faith imposes on us". It is only insofar as people believe that they are essentially their "soul" that any doctrine relating to what will happen after their bodily death makes sense. What is the relationship between the resurrected body and the soul? Is the resurrected body only a reconstituted body? If so, is it  the soul which gives the resurrected body its "identity"? But let's leave these difficult theological questions aside for the moment and examine whether or not there is any "evidence" of the existence of what is thought of as a "soul. To Anthony Flew, a philosopher who delivered a lecture on "Near-Death Experiences" at the conference "Science and Religion:", sponsored by the Center for Inquiry, Atlanta, Georgia, November 2001, the soul is "the experiencing, planning, deciding, incorporeal, spiritual substance which had been in charge of the flesh-and-blood person whose body it had been."To Jerome W Elbert the soul is "a very special part of a human being, in addition to the body, that gives a peson at least one of the following: life, a personality; or the ability to move oneself, to think and feel, to leave the body, to know right from wrong, to survive death and perhaps to be reincarnated, to exercise free will or to have a spiritual relationship with God." ( From the Mythology of Soul to the Conscious Brain 2001 ) But to me, the soul is something analogous to the software which runs our life, something which we ourselves write and will have to constantly rewrite within the constraints imposed by the motherboard (our genetic programme) during the lifespan of the computer (our body including our brain).


One of the ways believers of the existence of the "soul" attempt to justify such a belief is to rely upon the personal testimony of those who have undergone what has been called "near death experience" (NDE) or "out of body experience" (OBE). Are there any good grounds for such beliefs?  I shall examine Flew's article and also another article "Six Feet Over: A Computer stands by on an operating room ceiling, awaiting near-death experiences" by Mary Roach in her book Spook: Science Tackles the Afterlife (2005).


To Flew, OBEs, frequently reported by people who have recovered from unconsciousness during an operation, may have no cognitive status higher than that of dreams and are evidence only of the existence of of certain kinds of extrasensory perception (ESP), not evidence of some temporarily "disembodied soul" making an exploratory journey to another realm. "Even if sense can be given to the idea of a disembodied soul, the postulation of the involvement of such an incorporeal explorer would be grossly uneconomical. For having no body, and consequently no sense organs, any information brought back from its alleged travels would have to have been acquired by ESP, " says Flew.. 


What about NDE or experiences by people who came close to dying recalling having been to some places other than being blacked out on the operating table, traveling to the ceiling or hurtling through a sort of tunnel, often towards an all-encompassing light sometimes meeting dead family members or friends or sometimes a transcendental "presence". etc. First of all, such reports are typically made by the living! To constitute evidence of the existence of the soul, it must be shown that the information purportedly brought back by those encountering God or other saints etc. could only have been acquired when there were no evidence of any activity going on in their brain at the time when they were reported to be having such NDEs and that such NDE "were" the causes of their consciousness.


Michael Sabom, author of Life after Life (1975) who interviewed 116 cardiac arrest survivors and found  six such patients recalling specific details they had "seen" during their NDE or OBEs, in his Light and Death: One Doctor's Fascinating Account of Near Death Experiences (1998),  recounted the experience of one patient Pam who in 1991 underwent brain surgery to remove bllod from her brain for an aneurism, with her eyes taped shut, and molded, clicking inserts inside her ears and  reported being aware of each step of the procedure of the surgical team during her operation despite her EEG being flat.  But later, Sabom admitted that he himself was the "world renowned surgeon"  who conducted the operation mentioned in the book and that he himself was involved in the "structured interview protocol" by which the details of Pam's NDE were obtained. If it is possible that the patients heard anything, it is also possible that they might have partway opened their eyes and seen things and they would subsequently incorporate what they saw into their "reports". Some argue that the patients are merely unconsciously combining data from things they have seen or heard or felt together with their memories of TV medical dramas or previous hospital visits.


Numerous studies of the functioning of the human brain have, however, taught us that our brain functions by a number of different sub-systems each specialized in a particular sensory mode or a particular function, including the internal processing and monitoring of information within the brain itself and when we have a thought or a memory, that is just cumulative but "provisional" coming together of neural messages coming from such different parts our brain which happen to be resonating at the same frequency (either as primary wave or as harmonics and some scientists posit the theory that they do so at 40 hertz). Our memory is thus never a "direct" production but is always a "created", "fabricated" or "reconstituted" product. It is thus entirely possible that to explain certain sensations felt by his body during the operation, (in this case, why certain parts of our body "felt" the way they did) despite the knocking out of his "visual system" through the effect of anaesthetics), any "gaps" in the information needed for the generation of a "coherent" or "meaningful" overall pattern will be "filled in" by the brain itself. The brain does this by making use of data coming from other parts of the various sensory sub-systems by forming a "hypothesis" of what the "lost" data could have been through  "extrapolating"  the collective data retrieved from the store of his long term memory of how previously pattern A, pattern B, pattern C etc coming from the various sub-systems would by historical experience "always" happen or occur simultaneously and by matching the current data against such past "collective" patterns and trying for a "fit" for the most likely "explanation", it being known that memory from the different senses always occur in "clusters").The brain does this more or less in the same way that any modern car CD machine will extrapolate data "lost" when the laser head fail to read any data due to temporary break in the data stream as a result of mechanical dislocation of the laser head from the surface of the CD disc during a bumpy ride, to artifically "complete" or "fill in" or adding neutral data to the disrupted data stream to enable  the CD machine to continue to play a non-disrupted stream of music AS IF there had been no such temporary data stream disruption.


In short, what the patient reported as having been "seen" might in fact just be a "hypothesis" created by the brain itself to "explain", why he "felt" certain sensations at the various sites of his body being operated on (relying on the "residual" signals coming from the nerves of those parts being operated on, which continued to function as before the operation and indeed, as they always have been, below the threshold level of our normal "consciousness" or awareness). He therefore "reported" as a "fact" what in fact was merely a fact/experience based "hypothesis" that that "must" have been what he "would" see, had his visual system NOT been disabled by the anaesthetics AS IF  he actually "saw" what he thought he would have seen and without even knowing that that was what he was doing because such "information processing" occurred below the threshold of "normal" consciousness" or "awareness". 


Another criticism of Sabom's work is that he does not have any vigorous independent corroborative evidence of the truth of what his patients claimed when they said they "saw" their relatives. In a much cited example of a patient called Maria who claimed that in her wanderings outside her body, she saw a tennis shoe stuck in the third floor ledge of the hospital building, with a worn patch by the little toe and the lace stuck under the heel and later an investigator found the tennis shoe, exactly as described. But this has never been independently verified. We now also have abundant evidence that the sensation that we are no longer within our body may have been the result of the deprivation of oxygen to the part of the our brain concerned with our spatial orientation called the "visual orientation area".(VOA) The disruption of the normal functioning of the VOA may cause us to have the "feeling" that "we" are no longer within our own body but elsewhere . Alternatively, we may even artificially induce this feeling through the taking of "pleasure" psychotic drugs like ketamine, LSD, mescaline, pot, hash, or other hallucinogens or even extreme stress and endorphins..


In another study by Kenneth Ring and Sharon Cooper, some people who were blind from birth reported "seeing" their bodies lying below them and some said they "saw" doctors or physical features of the room. If so, these could count only as evidence of ESP, not evidence of the existence of a soul! Besides, the experiences described by their patients were never very clear. One woman described the experience thus: "It was like hearing words and not being able to understand them but knowing they were words". It was just a confused "feeling". . Many of the claims when investigated, were found to have fraudulent aspects..We need evidence, not anecdotes. Roach says, "It seems pretty clear what's going on ...People are experiencing something dazzling and euphoric and totally foreign, and interpreting it according to their image of heaven." These cultural overlays also apply to the reports of "rushing down a tunnel" sometimes reported by those who claim to have gone down a tunnel of light at the end of which they encounter God. The same applies to the reports of the "experience" of being sent back to return to one's body. Mediumship and "ghosts" fare no better! Most cases of mediumship seriously investigated also proved to involve fraudulent and dishonest elements, the spirit "appearances" being shown to be elaborately staged by frauds for monetary gains. Once scientific instruments were involved and a rigorous experimental protocols instituted, the spirit either failed to appear or alternatively the alleged "strange" phenomena could be explained by quite ordinary natural causes or the frauds were exposed.     .


In another famous study by Drs. Sam Parnia and Peter Fenwich in October 2000 at the Southampton General Hospital and later published in the January 2001 issue of Resuscitation, there was no direct measurement of the brain activity during the periods of the cardiac arrests. Another objection is that it is impossible to attribute any experiences recorded up to a week later to be the specific period that a brain purportedly went out of action. Thirdly, it is highly likely that a brain which had shut down might generate within itself some false information to fill in the gap of  what happened during the period of such temporary shutdown. Fourthly, we now have evidence that when the "visual orientation area" (VOA) in the temporal lobe of the human brain is put out of action or where its activity is retarded, then the patient will feel that the boundary between his body and the world will have altered such that his orientation in space will no longer function "normally:" and that may be the source of the patient feeling that "he" can perceive his own body "as if" he were outside of his own body and "as if"  it were floating somewhere above his own body and looking down at what was going on with that body on the operation table. To Flew, "only if the "putative memories" of the patients embraced information about the circumstances surrounding them when acquiring this information before they reported these putative memories would we be warranted to describe such cases as experiences had by the substantial "souls" of the patients. The editors of the Skeptical Inquirer therefore concluded that "the Southampton research showed that out of 63 cardiac arrest survivors, 4 exhibited some for the subjective attributes of NDEs. Not much to write home to mother about, really!"


In an article in the Lancet (2004), W Van Lommel who interviewed 344 cardiac arrest patients in 10 Dutch hospitals, who had all been clinically dead as defined by defrilliation on their EKG, found that only 18% of the patients had NDEs and therefore ruled out oxygen deprivation because if so, then all patients should report an NDE and concluded that " a state of consciousness ...in which identity, cognition and emotional function independently from the body but retain the possibility of nonsensory perception" and encourage practitioners to explore such phenomena. Such studies have been done. But their results are disappointing because the experimental protocols are found to be quite sloppy.


Bruce Greyson, who studied NDEs for 29 years thought that NDE was unlikely to be related to drug use. He noted that people under anesthesia but not close to death have far fewer NDEs than people who came close to death wothout being subjected to anesthesia and so concluded that it is hard to see how the drugs could be causing the NDEs.


Another renowned brain researcher, Susan Blackmore, a research psychologist who spent her life examining OBEs and NDEs and who wrote the books Beyond the Body (1982) on OBEs and Dying to Live (1993) on NDE, concluded in another article "What Can the Paranormal Teach Us about Consciousness" Skeptical Inquirer  March/April 2001, that "the more we look into the workings of the brain, the less it looks like a machine run by a conscious self and the more it seems capable of getting on without one.". In other words, it is not quite necessary for us to function with a "conscious" "soul", let alone one which will survive after our bodily death! This seems to tie in with my own reading of the functioning of the human brain in terms of its physiology, neurology and psychology.


沒有留言:

張貼留言