In fact, the author believes that phenomena such as near-death experiences and out-of-body separation are real to a certain extent, but I do not like "mysterious" explanations. In particular, the author is firmly opposed to religious concepts such as "soul" and "god". of.

is written in front of

. The following content may involve some seemingly "mysterious" topics. In fact, the author believes that the phenomenon of near-death experience and detaching from the outside of the body is real to a certain extent, but I do not like "mysterious" explanations, especially religious concepts such as "soul" and "god". Firmly opposed to this (of course, since most Westerners believe in God, it is reasonable for religious hallucinations to appear during near-death experiences). Therefore, this article also tries its best to describe near-death experiences from the perspective of scientific research, and the selected examples also have their sources. But even so, please don’t swallow these cases too quickly. After all, most of them are too old to be verified (the reason why there are many old cases is because tens of thousands of newborns were blinded due to excessive oxygen concentration in incubators that occurred in the United States around 1950. The concentration of events produced many blind people who could be subjects of investigation), and I believe there are many fictitious examples (either the researcher or the person being researched may have made them up). The author believes that the study of near-death experiences is indeed a very important topic for uncovering consciousness. After all, the near-death state is the closest state to that world that we can experience and possibly relay to living people. At the end of the article, I will briefly talk about the motivation for writing this article and the significance of this column.

Some early studies in Europe and the United States have found that people who have experienced medical death and are resuscitated may have special conscious experiences while in coma. There is still debate whether this near-death experience (NDE) is a visual image (hallucination) produced by the brain, or an event with some objective reality. To address this issue, an interesting approach would be to investigate the near-death experiences of people who were born completely blind. Because people who are congenitally totally blind have no vision at all, if there is no visual perception during their near-death experience, it can be concluded that the near-death experience is just an illusion of the brain; on the contrary, if there is a visual impression during the near-death experience, such as Without out-of-body disengagement (OBE) and correctly observing the surrounding situation, one cannot simply judge a near-death experience as a hallucination. Even if a person who is born completely blind can produce some kind of vision-based "imagination" through some currently unexplained brain mechanism in the extreme case of clinical death and experience external separation, it is difficult to explain it by hallucinations alone.

I Visual perception of totally blind people

(A) Eye-opening surgery

Even if "eye-opening surgery" is performed on congenitally blind people with impaired eye function and early blindness to completely cure their eyes, they will not be able to see immediately after the surgery. Because even if the eyes that receive external information are healed, the visual area of ​​the brain that processes that information is very underdeveloped because it has never been fed information. In order to be able to see, viewing experience is indispensable. Considerable recovery training is required before visual abilities are acquired. Many cases show that in the early stages after surgery, congenitally blind people can only feel the glare of light, but cannot recognize colors and shapes. Learning to recognize shapes is more difficult than colors. In addition, light can disrupt other senses besides vision, and some people even choose to close their eyes despite regaining their sight (von Senden 1960). People who are born completely blind lack the concept of height and distance, so they have no sense of distance. It is also difficult to distinguish two-dimensional objects from three-dimensional objects (Nathan 252~254). Research shows that the critical period of the visual cortex of the human brain is around 3 or 4 years old after birth. For people who have been blind for a long time since childhood, it will take more than a year to regain vision even if they undergo surgery to restore their sight as adults. The closer the blindness is to birth, the less developed the visual pattern is, and the more difficult it is to acquire vision (Valvo1968.19~24, Gelbart et al 615~621). The information processing mechanism in the visual area of ​​the brain of a person who is congenitally totally blind is very underdeveloped, so it is impossible to construct a visual image through data captured from the four senses other than vision. Therefore, it is generally believed that the visual perception during the near-death experience of a person who is born totally blind cannot be explained by the images (hallucinations) produced by the brain.

(B) The dreams of a totally blind person

usually cannot be perceived without using the five senses, but in dreams and hallucinations, sensory images can be generated even without the use of the five senses. Moreover, this ability does not require a learning process and can be achieved immediately. So, is the special experience that occurs when a near-death experiencer is in a state of clinical death where the five senses are disabled, is it a dream? The answer to this question can be explored by investigating whether the dreams of totally blind people contain visual images. Research on this point has now reached the following conclusion: There is no visual perception in the dreams of people who are congenitally blind, and they are only composed of other senses. On this point, it can be said that researchers have basically reached a consensus (Blank159, Kirtley171 , Deutsch293, Ramsey434, Sullivan38.52~53). However, there is somewhat of a debate about the relationship between age of blindness and visual perception in dreams. According to D.D. Kirtley, people who are blind before the age of 5 have no visual perception in dreams, and people who are blind between the ages of 5 and 7 may or may not retain visual perception (171). P.Nathan believes that people who are blind before the age of 3 will not retain visual perception, but people who are blind after the age of 4 can experience vision (255). According to H.R. Blank, the critical period is between 5 and 7 years old (160). Although there are rare exceptions, people who are blind before the age of 5 almost never have visual dreams, while people who are blind after the age of 7 retain visual perception (173). N.Kleitman also maintains that the dreams of people who were blind before the age of 5 lack visual perception (102). Based on the above, we came to the conclusion that the divergence point is roughly around 5 years old. But there are also individual differences, and even in cases of blindness before the age of 5, there are examples of residual visual perception (Deutsh291, Blank159).

One thing to note here is that even if one becomes blind after the age of 5, the visual images produced in dreams can only be the content of the past memory before the blindness, and will not be the memory of the person's near-death experience or out-of-body separation. In addition, even if a blind person retains the memory of visual perception after the age of 5, the clarity of this memory will inevitably weaken over time and eventually disappear (Kirtley171, Ramsey434). In contrast, there are reports that memories of near-death experiences remain vivid for years. In short, the divergence point of 5 years old is considered to be related to the critical period of visual cortex development of the human brain in early childhood, which is around 3 to 4 years old (IA).

(C) The visual response of blind people to hallucinogens

As mentioned above, it was confirmed that people who were blind before the age of 5 also have visual perception in dreams, so how will blind people react to hallucinogens such as LSD? Regarding this point, there are the following experimental results. After administering LSD to 24 completely blind people, all 13 people who had had spontaneous visual perception before gained visual perception due to LSD. However, the completely blind people who had no previous visual experience were unable to experience any visual perception. In addition, although the visual hallucination mechanism of LSD is independent of the retina and higher-level visual pathways, a visual system with a certain degree of functionality is necessary for LSD to produce visual hallucinations (Krill et al 184~185). Similarly, when other researchers used LSD on two blind people with complete optic nerve atrophy, the blind person who had had spontaneous visual experiences would have hallucinations, while the blind people who had never had visual experiences would not, but the retinal potential map of the blind person Similar to normal people, this also proves that the generation of LSD hallucinations does not require the retina or higher visual pathways (Rosenthal242). There are many other experiments: When researchers administered LSD to people who were congenitally blind, there was no visual response (Rinkel 235, Hoffer 44.77.). In addition, other researchers administered LSD to blind people (optic nerve damage) who had previously had no spontaneous visual perception, and there was no visual perception response. In addition, LSD was administered to two blind people with binocular visual neuroatrophy, but no visual perception was produced. In contrast, LSD was found to produce visual hallucinations when administered to totally blind people (both eyes removed) who had previously had spontaneous visual experiences (Krill et al 183), and to 10 blind people who had previously had spontaneous visual experiences. Mescaline, also produces visual hallucinations (Zader 127). It can be concluded from the above experimental reports that htmlblind people who were blind before the age of 35 and have never had visual experiences such as dreams will not have visual hallucinations even if they take hallucinogens.

II Blind people's near-death experiences

Kenneth Ring, with the assistance of the American Association of the Blind, investigated examples of blind people's near-death experiences. He found 16 blind people who had had near-death experiences, 10 blind people who had experienced out-of-body experiences in non-near-death states, and 5 blind people who had experienced both, a total of 31 blind people (1997.106). Ten of the 21 people who had near-death experiences were completely blind before the age of 5, and 4 of the 10 who had non-near-death experiences outside the body were completely blind before the age of 5. Therefore, the total number of people who were completely blind before the age of 5 was 14 people. Eleven of these 14 were due to retinal disease of premature infants (retrolental fibroplasia) caused by excessive oxygen concentration in premature infant incubators between 1946 and 1958. Two of them were born completely blind, and one was born between 4 and 5 years old. Both eyes were removed before the age of 10 (1997.107). Among the 21 near-death experiencers, 20 experienced the feeling of comfort, happiness and being loved, 14 left the body, 10 saw their own bodies, 8 passed through a dark tunnel, and 12 interacted with others ( The Holy Spirit, angels, religious figures) met, 8 saw a shining light, 7 heard music and voices, 4 retraced their lives, 6 encountered a barrier, and 10 were told to return to earth or asked to choose whether go back. These reports are generally consistent in nature with elements of NDEs in non-blind people (1997.114). Among the 21 blind people who experienced near-death experiences, 15 felt visual images during the near-death experience. Nine out of 10 blind people who have experienced out-of-body detachment in non-near-death situations have visual experiences during out-of-body detachment. Adding in the five blind people who had both near-death experiences and non-near-death escapes, 13 out of 15 experienced visual perception at that time. A total of 24 blind people had visual experiences in a near-death state or outside the body, accounting for about 80% of the total (31 people). 9 out of 14 people who were blind before the age of 5 have clear visual experience, accounting for 64% of the total (1997.115). It is reported that 10 out of 21 blind people who experienced near-death experiences saw their own bodies at that time. Seven out of 10 blind people who had experienced out-of-body separation while not in a near-death state testified that they saw their own bodies at that time. In both cases, some people saw the medical team treating them, various features of the ward and things around them. In addition, among the blind people who have had near-death experiences, there are examples of seeing supernatural things such as light bodies, supernatural scenery, angels or religious figures, dead relatives, etc.; among the blind people who have experienced external separation in non-near-death states, there are also cases of seeing supernatural things. to instances of supernatural things such as light, beautiful colors, or otherness. One thing to note here is that congenitally blind people should not even understand the concepts of light and darkness. A blind person who has gained visual perception without being detached from a near-death state can describe in detail the scenes on the ground or in the supernatural at that time, which sounds very complete and realistic. This is also the case for non-blind people (Ring 1997.125).

Kenneth Ring (1936~ )

(A) Examples of near-death experiences of people who were born totally blind

Let’s look at some typical examples of near-death experiences of people who were born totally blind.

① The near-death experience of Vicki Umipeg, a woman who was born completely blind (Vicki1~8, Ring 1995). Vicki was born in california in december 1950. Because he was born prematurely, he was placed in an incubator with an air valve. At that time, due to excessive oxygen supply in incubators, approximately 50,000 American premature infants were completely blind due to optic nerve damage from 1947 to 1952. The optic nerves in both eyes of this woman were damaged, so she never had a single visual experience. I have never seen light and shadow, and I don’t know the concepts of light and color. There is no visual image including light, shadow and color in my dream. She had two near-death experiences. Here, first, let’s take a look at her experience of having visual perception for the first time in her life.

Vicki Umipeg

First near-death experience (12 years old, 1963)

received emergency treatment for appendicitis and peritonitis . From near the ceiling, she saw her own body on the metal operating table, ready for surgery. She realized it was her own body. She didn't know what color was, but noticed that the sheets on the operating table glowed with different brightnesses (which she later discovered were colors). Instead of seeing colors, she perceived changes in light.It is important to note that color recognition is impossible for people who are congenitally blind). She is then sucked into the dark tunnel. As she walked through the tunnel she saw people with physical gestures. She saw the faces and upper bodies of people ahead of her. A bright light shines in front of the tunnel. When entering the light, my whole body feels that this is home. Then the scene flashed back to the past: the statue of Christ on the cross that was cherished by Bunny, a female friend from the blind school days (who had died at that time), was stolen by Vicki. Bunny looked for it anxiously. Vicki fully understood Bunny's sadness during the experience. Vicki saw what she was doing as a blind person and could see for the first time in her life. She was struck with awe. There is light at the end of the tunnel. She also saw flowers and grass. I met Debby, another female friend from the blind school days (who had passed away at that time). The neighbor Mrs. Z. (who had died by then) was also there. I also met another female friend from the blind school days named Diane (who had passed away at that time). Diane and Debby look happy and beautiful. Debby was fat when she was alive, but not now. Debby was very happy to see Vicki and extended her arms to Vicki. Finally, a figure with a brighter light than the others (Vicki thinks it is Christ) appears, wrapping her in love and peace. The man said: "You have to go back and learn to love and forgive." The next moment, she returned to her body.

Second near-death experience (22 years old, 1973) (Vicki1~8, Ring1995,1997.109~112). When

was working as a singer at 's nightclub in Seattle, one night after get off work, she was driving home with two drunk guests. There was a traffic accident and Vicki suffered fatal injuries. He suffered a fractured skull, concussion , injuries to his neck, back and one leg, and it took him a full year to be discharged from the hospital. She lost consciousness but suddenly "awoke" above to see her body lying on the road. She watched as paramedics arrived, tore off her clothes and placed her on a spinal brace. Next, Vicki remembers seeing a male doctor and a woman rescuing her from near the ceiling in the emergency room. Vicki heard the woman say that her eardrum was bleeding and she might become deaf. Vicki tried to talk to the two, but there was no response. Vicki could tell from the wedding ring on her finger, waist-length hair and tall and thin figure that the body lying on the operating table was her own. Suddenly she walked across the roof of the hospital and saw the lights of the city. Everything can be seen from the roofs of buildings, streets and hospitals. She was extremely pleasantly surprised. But soon she was sucked into a dark tunnel-like object, and then passed through the tunnel, facing a world of light. Flowers, grass and trees were seen there. She saw the light. Everything seen is caused by various subtle differences in light. Everything shines with light and radiates love. She met Debby and Diane, her classmates from the blind school. Both of them looked happy and beautiful. Mr. and Mrs. Z., who had taken care of her when she was a child (both deceased at that time), welcomed her. Vicki's grandmother also came (she died two years before her second NDE). Then, the glorious figure appeared and said to Vicki: "You have to go back and learn to love and forgive." So the next moment she realized that she had returned to her physical body.

It can be seen that Vicki’s two near-death experiences are essentially the same.

② The near-death experience of a completely blind man named Brad Barrows (Ring1997, 112~113).

In the winter of 1968, Brad experienced a near-death experience (at the age of 8) at the Boston School for the Blind. He developed severe pneumonia and had difficulty breathing. The nurse said his heart stopped for at least 4 minutes and performed CPR. When he couldn't breathe, Brad floated from the bed to the ceiling and clearly saw his lifeless body on the bed. I also saw a blind classmate getting up from the bed and running out of the room to ask for help (this classmate testified that this was true). Brad floated from the ceiling onto the roof of this building (this incident is estimated to have occurred between 6:30 and 7am). He saw lots of clouds, dark skies (there had been a snowstorm the day before), and snow everywhere except in the streets. The streets were still slushy, but the snow had been removed.Brad saw the snowdrifts formed after shoveling the snow, saw the municipal tram running, and also saw the students on the playground of his school for the blind and the special hill he often climbed. "I saw those things clearly. Completely clear," Brad said. Then he walked through the tunnel and into the vast grassland blessed by the light. He saw a path surrounded by tall grass and tall trees with broad leaves. There was no shadow there. He saw sparkling stones. The brilliance of those stones makes people feel warm. Later, he met an unknown person who made Brad return to the ground. When he regained consciousness, he had returned to his physical body.

③ Fred Schoonmaker, a heart doctor in Denver, Colorado, told the story of a woman who was born completely blind and left her body during a near-death experience. She correctly stated the number of medical team members (14) in the operating room at the time and the rescue situation. The woman was unable to recognize the colors seen during the detachment, but could see shapes and movements (Blackmore 1993.133, Ring&Lawrence 224.).

(B) Examples of the visual experience of blind people who become blind after the age of 5

As has been pointed out, people who are completely blind after the age of 5 will still retain the visual image before losing their sight, but these are facts in the past, not endangered. The current situation of death experience or out-of-body separation (IB), so the cases of near-death experience of people who are completely blind after the age of 5 are also very important.

( a ) Visual image of near-death experience

① The case of a 70-year-old woman living in Long Island (Moody171). The woman became blind when she was 8 years old. He suffered a heart attack at the age of 70 and was resuscitated. After recovery, she correctly described the resuscitation treatment she received, the blue shirt the doctor wore at the time and the shape and color of the equipment used. The important thing here is that most of the devices used at that time did not exist more than 50 years ago when I still had sight. It is almost impossible to correctly judge the color and shape of a medical device that has never been seen before using senses other than vision. The doctor wears a blue shirt. If you are familiar with medical treatment, you may know this.

In this case, because there is no clear record that the woman was outside the body, there is a logical possibility of clairvoyance.

② Several people who had completely lost their vision for more than 10 years in the past 10 years or so were separated from the body during emergency treatment and saw the styles, colors, patterns of the clothes and ties of the people around them, and even the colors of the gemstones they wore. It was also right who entered the room first and who performed the resuscitation measures. (E.kübler-Ross.22.96, E.kübler-Ross 1995.72.88, 1988.282~283, E.kübler-Ross 1985.307)

In this case, the report is very simple, so it is unclear whether the above information was obtained through hearing and touch. possibility.

③ At the age of 22, a man who was completely blind due to a sudden illness saw his own body, doctors and operating room during a near-death experience. The man said, "I can see. I see everything. In the IED, all the details are seen." (Ring 1997. 116)

In this case, there is no record of what the blind man saw during the IED. Whether the matter is strictly consistent with the facts. There may also be ordinary things that anyone can imagine.

④ A blind chemist, who was nearly dead in an accident a year later, visually reported the surrounding situation in detail and accurately. (Habermas et al 1992.75, Andersen1980.91)

In this case, did I really escape from the body? Is the situation around you guessing something that anyone can imagine? Detailed aspects such as whether correct guessing information can be obtained using senses other than vision have not been reported.

⑤ A man who lost his sight in a car accident at the age of 19 had a near-death experience when he saw his dead grandmother comforting him while crossing a valley. I said: "I was completely blind in the accident, so I had no vision. But the image of my grandmother was very vivid and clear at that time." (Ring 1997. 116)

In this case, the man had a grandmother until he was 19 years old. Therefore, during the near-death experience, we can also consider the possibility that a vivid visual image of the grandmother appeared due to a life flashback.

( b ) The visual image during the non-dying state of external escape

① This woman was about 20 years old and became blind due to intraocular hemorrhage. In the summer of 1972, I spent every weekend at my boyfriend's apartment. One Saturday night in July, two people slept in a very hot bed and were still awake at two in the morning. She tried to sleep, but suddenly noticed that she was standing in the right corner of the bed, and her viewpoint was near the ceiling. From above she saw herself sleeping in bed with her boyfriend. She was surprised to see her body clearly. She knew without a doubt that this was definitely reality and not a dream or hallucination. The next morning she made sure there was no place in that bedroom to look down from that position. (Davis-Cambridge 180~182) If this example is interpreted as a dream that fulfills the wish of a blind man, it does not explain why the viewpoint must be near the ceiling. Because it is an event during sleep, the five senses are not directly involved. However, the scene itself of sleeping with your boyfriend in bed is easy to imagine.

② An American named Frank became completely blind in 1982. After that, he could no longer see anything, including light and shadow. Ten years later, in 1992, Frank went with his girlfriend to attend the funeral of a deceased friend. On the way, his girlfriend bought him a tie at a clothing store. Because his girlfriend had other things to do, she gave Frank the tie and left temporarily without specifying the style and color of the tie. Frank put on his tie and lay on the sofa when he suddenly jumped out of his body and saw his own body. He found that the tie was red with two gray circles on it. When his girlfriend came to pick him up soon, he told her the information about the new tie. The girlfriend initially thought someone else had told him, but that wasn't the case. She herself later testified that she did not tell Frank anything about the new tie (Ring 1997. 120~121). In this case, it is unclear why the extracorporeal detachment occurred. It's clear that Frank captured information that is inaccessible to senses other than sight. The possibility of a sudden acquisition of clairvoyance cannot be logically ruled out, but it does not explain the need to detach from the body and see from above.

③ A Californian woman named Nancy was blinded when she underwent a biopsy for a chest tumor in 1991 due to a doctor's mistake in cutting off a large vein and sewing it shut. She was placed on a gurney to be transported for vascular imaging, but panicked medical staff bumped the gurney against the elevator doors. At this moment, she was out of the body, floating on the gurney, and saw her body wearing a ventilator below. Her son's father and her current lover could be seen standing in shock in a nearby hall. The two people just stood there blankly, not approaching her. This, in later interviews with her lover, was proven to be true in detail. Nancy was wearing a ventilator and her field of view was blocked. She should not be able to see her lover and her son's father in the hall. Moreover, judging from medical records and other evidence, she was indeed completely blind when the external separation occurred (Ring 1997, 122~124). Nancy in this case is not a person who has been blind for a long time, and medical science does not rule out the possibility that the impact when she hit the elevator door temporarily restored her vision. The report does not mention whether Nancy was notified before or after the accident that her son's father and her current lover were visiting her. In this case, the possibility of suddenly developing clairvoyance cannot be logically denied, but even this does not explain the need to leave the outside of the body and look from above.

III The possibility of using reasons other than dreams (hallucinations) to explain the visual perception of congenitally blind people

An explanation of the reasons why people who were blind before the age of 5 can obtain obvious visual experiences in near-death experiences despite having no visual perception at all. , are there other possibilities besides dreams (hallucinations)?

(A) Skin Vision

According to J. Grinberg-Zylberbaum, 19 normal children aged 5 to 13 were gathered together for training and developed the ability to see without the naked eye. The visual image even has the same rules of perspective, contrast, acuity, and motion as vision on the retina.One of the subjects was said to be able to see not only what was in front of him, but also what was behind and to the sides. There are also several children who can perform internal fluoroscopy on others and describe the location of fractures and the extent of injuries a few years ago. It is noteworthy that 360-degree vision and intracorporeal vision are also found in examples of out-of-body near-death experiences. The

article also attempts to explain this decoding mechanism of visual objects without using the naked eye through quantum theory (141~158): the brain generates an energy field (neuron field) that interacts with the spatial structure (quantum field), This interaction creates interference patterns similar to the holograms that make up the energy structure of perceptual experience. This structure then interacts with central information processing to produce visual experience and perception. Without retinal activity, the neuronal field would lack normal visual elements, but would still interact with the visual elements of the quantum field.

Of course, it must be noted that J.Grinberg-Zylberbaum is just a layman in physics. Some physics majors will probably be pissed off when they see the explanation in the previous paragraph. The author personally cannot agree with this explanation, but after all, this is not the focus of this article, so I will not delve into it here.

Jacobo Grinberg-Zylberbaum (1946~1997 (missing))

B.W. White et al. used a vibrator that translated the signal of the video recorder into a tactile stimulation pattern on the back skin to blind people (25 people who were born blind and who became blind in late childhood) The experiment was conducted with 5 persons) and non-blind persons. As a result, both were able to correctly recognize objects through skin stimulation after training. First, fix the video recorder and ask the subject what the object is. The subject perceives the object through the back. Then, when the video recorder is moved to simulate visual scanning, the subject can also judge by feeling where the object is located outside the field of view in front of him (23~27). The same method was used to test 16 blind people. After short-term training, they can recognize geometric patterns, depth, surrounding objects, facial photos, words, etc. Two of them were born completely blind. A person who becomes blind at the age of 4 needs about 50 hours of training. People who are blind from birth acquire abilities more quickly than those who are born totally blind (Bach-y-Rita et al 963~964).

The results of experiments conducted by A. G. Novomeysky on people who were acquired blindness showed that skin vision depends on the brightness and the size of the surface of colored objects. By sensing with the palm of your hand, you can recognize achromatic colors after 2 months of training. Not only that, but it can also distinguish the colors of various crayons and identify the surfaces of different colored substances independently of the background color. After being stimulated by the metal plate, the skin's vision is strengthened. When the metal plate covers the color, especially the perception of the mixed color is weakened. A. G. Novomeysky speculated that visual experience before blindness played an important role. He also claimed that congenitally blind people can only distinguish red from blue. In addition, blind people can perceive geometric patterns, text, etc. without touching, but moving hands and fingers is essential. And with one hand, you can draw the outline of a shape placed 2-3cm below. The reading process will be faster if the questionnaire is placed on a metal frame, and the hand position can be kept higher if the light is dimmed. The subjects also identified the numbers under the aluminum plate, but had difficulty distinguishing the numbers (341~367) under the 4mm thick glass plate.

Sheila Ostrander and Lynn Schroeder report on a completely blind Russian woman named Rosa Kuleshova who has been training for several hours a day for 6 years since 1962. The results show that even with their eyes covered, they can use their fingers to identify colors, read text, and identify the appearance of people in photos. Other groups covered her eyes and sat in a shelter using copy paper, cellophane, or colored paper placed under the glass plate. She guessed the colors correctly and could even read the text underneath the glass plate. and sheet music. Experimental results show that she is not identified by skin contact and temperature difference (Ostrander et al. 342~345).

Sheila Ostrander (right) and Lynn Schroeder (left)

R. Maublanc reported that Mrs. Leila Heyn, who was born totally blind, underwent long-term training until she could see with her hands. Having never seen colors, she could distinguish red and yellow, but not blue. Her sense of color was unstable and capricious, and her inability to distinguish between light and dark lasted for a long time. Putting the barrier between the face and the coloring material, and feeling the heat and thickness with your fingers, you can distinguish yellow from red, but the error rate when distinguishing yellow from blue is about 33%. After training for more than 3 months, you can read text with your fingers, but the perception of color and text will be mutually exclusive. After further repeated training, you can also identify the color when choosing a dress from the wardrobe. Red and yellow are easy to distinguish, but blue and purple are easily confused, and blue is the most difficult color to identify. Because white represents the normal state, white cannot be imagined, but black can be seen. Since I didn’t know the name of the color at the beginning, I just felt the difference in color. In order to see color, it is necessary to go through various steps. In addition, the perception of shapes and colors are different modes of perception, but the perception of shape and color can be completely distinguished through the face and hands (Duplessis 59~63).

In 1964, Dr. Georgi Lozanov (Bulgaria) covered the eyes of 60 children who were born blind or blind since childhood, and set up an opaque barrier between the children and the object to conduct experiments. Three out of 60 people were also able to visually recognize colors and geometric shapes through their skin when the shapes and colors were covered with a glass plate. The remaining 57 people also mastered skin vision through training. Because the colors have not been seen, it is necessary to teach the names of the colors (Ostrander et al. 571~572).

Georgi Lozanov

Nelya (female), who became blind less than a year after birth, can recognize colors hidden under glass plates after a short period of training, and can read text after five and a half months of training (Ostrander et al. 353~354).

A Russian woman named Mary Wimberley, who was completely blind at the age of 18, had one eye removed and the optic nerve of the other eye severed. After several months of training, she can distinguish black and white 100% correctly and can also identify in the dark. color. Experiments showed that she did not identify colors through touch (Moss 98~100).

R.P.Youtz speculated on the mechanism of skin vision based on experiments on people with skin vision abilities. The skin can also perceive different wavelengths in the electromagnetic spectrum by sensing the difference in reflected heat (infrared rays) emitted from the colored card, so it can identify colors based on differences in temperature or differences in wavelengths emitted by objects (37~41)

M.Smirnov The idea that skin vision is caused by touch and thermal sensations was also denied from experimental examples. And he believes that this is not caused by the special structure of the skin receptors, but by the potential that can be activated through training to analyze the signals relayed by the receptors from light (Duplessis89).

Ostrander believes that all parts of the skin may have potential vision, and that with training, all people can see with the entire skin (Ostrander et al. 66). The retina is a specialized structure for vision formed due to the specialization and evolution of the skin. The skin itself also has a visual basis, but its function will degrade if it is not used for a long time (vom Senden, Valvo 1966).

Dr. Goldberg found that although people who are blind due to eye and optic nerve disorders can develop cutaneous vision, cutaneous vision is not possible in people with disorders of the brain's visual centers (Ostrander et al. 364). If this statement is correct, and if the visual center of the brain of a congenitally blind person is not damaged, skin perception may also be possible.

For people who were blind before the age of 5 and had no visual perception, does skin vision suddenly work like this? There was no skin vision before the near-death experience. Did skin vision suddenly appear due to some state changes in the brain during the near-death state? There are specific differences between the two, so they cannot be treated equally. As K. Ring also pointed out, in order to master skin vision, it takes a long time to train to gradually obtain obvious vision from the initial state of total blindness.In contrast, in near-death experiences and out-of-body situations, clear vision is experienced immediately without any training (1997. 131~132).

htmlRobert V. Hine, who lost his sight at the age of 350 (Robert V. Hine; professor of history at the University of California), to some extent, mastered the cutaneous sense of identifying direction and distance through sound waves and hearing, so that cutaneous vision is the condition of people who were blind at an early stage. It is possible, but becomes difficult with age and takes a long time to learn (Haine 1997.228). Tom Sullivan, who was born completely blind due to retinopathy of prematurity, can identify the object and its size by capturing the tiny vibrations transmitted in the air with his face, but there are very few blind people who can master this kind of skin vision (Sullivan found out from 1,500 people Only 3 cases were found in the school for the blind), and Sullivan himself often failed and bumped into concrete pillars (Sullivan 14. 89~90).

"Second Sight" author Robert V. Hine

(B) Blindsight

Patients with partial or total loss of the primary visual cortex (V1) cannot see anything consciously (no visual perception), but they Moving stimuli can be judged (Weiskrantz 1986), a symptom known as blindsight. It is generally believed that blindsight can locate stimuli and detect motion. There is a saying that blindsight can distinguish not shapes but the inclination of lines (Weiskrantz1987.77~92). Information reaching the association area through pathways other than V1 cannot produce consciousness. For example, there is a pathway that reaches high-level pre-visual areas such as the MT area via midbrain parts such as the superior colliculus and thalamus, which are called the second visual system. However, in the human brain, the superior colliculus visual system is lower than the cortex and cannot produce consciousness (but for more primitive animals such as frogs, the superior colliculus is the center for visual information processing. Therefore, blindness can also be said to be caused by the cerebral cortex. Injury awakens “abilities” arising from evolutionarily primitive brain functions). In addition, there are few but direct pathways from the lateral geniculate body (LGN) that project to the extrastriate cortex (Yukie & Iwai 81-97, Fries 73-80). The V4 and V5 regions were identified as being included in the termination site of the pathway. When a stimulus is presented to the blind visual field of a blind person, the induced response to the stimulus signal will be directly recorded by the cortex, indicating that such a pathway to the cortex also exists in the human brain (Celesia et al 862~869). Furthermore, two information processing pathways were identified in the visual system of the monkey brain. 1. The ventral pathway running from V1 of the occipital lobe along the temporal lobe is mainly responsible for recognizing objects (shape and color, what). 2. The dorsal pathway running from V1 of the occipital lobe along the parietal lobe is mainly responsible for recognizing space (movement and position). , where) (Unger leider et al).

Lawrence Weiskrantz (1926–2018)

According to M. I. Posner and M. E. Raichle’s experiments on blindsight patients, assuming that the “what” pathway is involved in object recognition and the “where” pathway is involved in the orientation of attention, then even if the “what” pathway cannot be used, Intentional perception can also use the "where" pathway to locate the direction of an object. R. Graves and B. Jones also demonstrated through experiments that healthy people can also orient invisible objects (Posner et al 208~209). It can be seen that the discriminative visual response to the orientation of an object is performed unconsciously. This dissociation between conscious and unconscious responses suggests that the processing of visual information that underlies conscious perceptual judgments and the neural mechanisms that automatically regulate visual motor behaviors such as hand reaching or eye movements are at some level in the brain. Work independently (Goodale et al 154~156).

Can the visual perception produced during the near-death experience of a congenitally blind person be explained by blindsight? V. Krishnan hinted at the possibility of memorizing the location of an object when separated from the body (1993.258~259), but could not explain the fact that the object can be visualized to the extent that it can be distinguished.As K. Ring also pointed out, 1. Blindsighted patients do not realize that they can see things, but in the near-death experience of blind people, the blind people claim that they can see things clearly; 2. In the case of blindsight, The patient cannot express the object in words, but the blind person can use words to describe what he sees when he is out of the body. Therefore, blindsight and the near-death experience of a blind person are completely different phenomena. So is it possible that blindsight patients can also develop visual perception in a brain abnormal state such as near death? Although this possibility cannot be completely denied, there is currently no brain mechanism that can explain this possibility scientifically. There are other differences between cutaneous vision or blindsight and the phenomenon of extracorporeal detachment. As V. Krishnan also pointed out, when being separated from the body, it can only be observed from an overhead perspective. If the doctor bends forward and bends over the body of the person who is separated from the body, he can only see the doctor's back but not the back. Face. Such a fact (1985.34) is difficult to explain in terms of skin sensation or blindness. Even the use of clairvoyance (supersensory theory) cannot account for the need to detach oneself from the outside of the body and see from above (Krishnan 1982. 21).

Some conclusions

① Totally blind people who lost their sight before the age of 5 will not have any visual perception even in dreams (even if there are some personal differences).

② For completely blind people who become blind after the age of 5, the past visual impressions before blindness can be retained, but they will gradually disappear as they grow older.

③ 80% of blind people have visual perception during near-death experiences or non-near-death out-of-body escapes. There are also examples of completely blind people who correctly observed their surroundings during out-of-body escapes. Judging from ①②, such an experience can be said to be a strange phenomenon that deviates from modern scientific common sense. What exactly these mean is a future issue.

Naturally, we did not draw any very important conclusions in the end. But we can at least detect some of the peculiarities of consciousness. Is consciousness really something different that cannot be explained by science and is completely separate from matter? In fact this is something I want to write about in some of my next articles. However, I can give my own psychological answer here: consciousness, like other substances, is not a special existence that cannot be explained. However, precisely because of this, it is necessary for us to introduce the concept of "consciousness" into natural science and explore it within the scope of science. Scientists who oppose idealism are often reluctant to touch topics like consciousness, but the author believes that incorporating the concept of consciousness into science as a general object to study is the best way to avoid consciousness being elevated to a pedestal.

So, is there any connection between consciousness and natural science? Of course there is. Needless to say, brain science and neuroscience, here can be said to be the most direct dividing line between matter and consciousness - consciousness is generated from matter and acts on matter. But this is only a macroscopic appearance, and the mechanism of "production" and "action" must still be answered through physics. Physically, we can see some joints. Many friends may bring up "wave function collapse" and "quantum entanglement" in quantum mechanics. Although we may have seen many related popular science and academic materials, we have to say that research involving consciousness is non-mainstream in both ontology and epistemology. It is easy for a layman to say that consciousness causes the collapse of the wave function, but it may just be a laughing stock for an expert. Although the author is not a professional in this field, from the bottom of my heart I still expect that consciousness and quantum mechanics can be related. Penrose, who recently won the Nobel Prize, has also put forward some insights into the macroscopic quantum effects produced by the "microtubule" structure in the brain, but there does not seem to be much in-depth research and results.

In addition, if we want to study consciousness as an objective reality, the "informatization" of consciousness may be necessary. Regarding this point, the Information Integrated Theory (IIT) proposed by neuroscientist Giulio Tononi is a theory that currently seems to have a preliminary foundation (but it is still far from truly explaining consciousness).