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Wednesday, October 19, 2016

Blindsight

I'm going to discuss a subset of reported NDEs and OBEs. Let's put this in context. According to physicalism, mental events are neurological events, so all cognition is located inside the skull. Hence, the brain can't perceive the external world apart from the five senses. If so, then knowledge of our physical environment must be mediated by one or more of the five senses. If, however, there's evidence that some people born blind have near-death or out-of-body experiences in which they perceive their concrete surroundings, then that falsifies physicalism. 

And that's significant because atheism typically rejects dualism in favor of physicalism. I think that's because, if physicalism is true, then at one stroke that rules out the existence of minds that are, or can be, independent of brains. In other words, it rules out God, angels, demons, and immortal souls. A very economical way to disprove Christianity.

Although some atheists make allowance for platonic realism, they generally labor to avoid that. Moreover, even if platonic realism were true, that's a different kind of dualism than brain-independent minds. So it lacks the same polemical value for atheism. 

I have read efforts to explain this away. For instance:

[These cases] may be inspired by accounts of other people's NDEs that have been widely disseminated in various forms of the media. That is, might a blind person have heard that people see certain things in a near-death encounter and unconsciously generated a fantasy that conformed to this belief? 
http://infidels.org/library/modern/keith_augustine/HNDEs.html#blind
Light enhances brain activity during a cognitive task even in some people who are totally blind, according to a study conducted by researchers at the University of Montreal and Boston's Brigham and Women's Hospital. The findings contribute to scientists' understanding of everyone's brains, as they also revealed how quickly light impacts on cognition. "We were stunned to discover that the brain still respond significantly to light in these rare three completely blind patients despite having absolutely no conscious vision at all," said senior co-author Steven Lockley. 
https://www.sciencedaily.com/releases/2013/10/131028090408.htm

There are, however, problems with that appeal to discount reported NDEs and OBEs of people born blind (or the functional equivalent). It is, of course, true, that the brain (or mind) can play tricks on us. And the brain (or mind) may have the capacity to simulate abstract images like migraine auras. 

But how could the brain simulate representational images that correspond to the sensible world? I've read that congenitally blind people dream, but their dreams are auditory or tactile rather than visual. That's because the imagery of dreams derives from sensory perception. Because our memory is stocked with mental representations of what we've seen, that supplies raw material for the imagination. The mind can reproduce or modify that information. But imagination needs something to work with. It can't operate in a vacuum. 

Finally, a last-ditch response is to dismiss the reliability of testimonial evidence. That, however, commits the atheist to a devouring skepticism that atheism cannot afford inasmuch as atheists depend on the general reliability of testimonial evidence for much of what they believe. 

I'm going to quote from an article that gives some case-studies. It would be useful if researchers were to investigate additional cases. I'm a bit wary about the the risk of overreliance on a single study. In fairness, it isn't easy to isolate and identify people born blind (or the functional equivalent) who've had NDEs and OBEs. That's a subset of a subset of a very select group to begin with.

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In order to recruit qualified participants for this study, that is, blind persons who believed they had had either an NDE or an OBE,we first made contact with 11 national,regional, and state organizations for the blind, to solicit their help in locating potential respondents among their membership.

After an individual made contact with us, we conducted a screening interview over the telephone to make sure that he or she had the appropriate qualifications for our study. Specifically, we determined the sight status of the person and made sure that he or she had undergone either an NDE or one or more OBEs, not necessarily associated with a near-death crisis. Once the person's eligibility for the study was established, we either then continued with the formal interview or scheduled a second call for that purpose. In a few cases, one or more follow-up calls were necessary to clarify some aspects of the respondent's account. In the interview, we took a detailed sight history from the individual and then conducted an in-depth probe about his or her relevant experiences...All conversations were tape recorded with the permission of the respondent, and transcripts based on these conversations were later prepared, to permit detailed analysis of our findings. Finally, each participant who expressed an interest to receive information about the findings of this study was sent a summary at its conclusion.

Vicki was born very prematurely, having been in the womb only 22 weeks at delivery, and weighed just three pounds at birth. Afterward, her weight dropped precariously to one pound, 14 ounces. As was common for premature babies in the 1950s, she was placed in an airlock incubator through which oxygen was administered. Unfortunately, because of a failure to regulate the concentration of oxygen properly, Vicki was given too much and, along with about 50,000 other premature babies born in the United States about the same time, suffered such optic nerve damage as to leave her completely blind. As she made clear in an initial interview with another researcher, Greg Wilson, who kindly provided his tapes and transcripts to us, she has never had any visual experience whatever, nor does she even understand the nature of light:

Interviewer. Could you see anything?
Vicki: Nothing, never. No light, no shadows, no nothing, ever. 
Interviewer: So the optic nerve was destroyed to both eyes?
Vicki: Yes, and so I've never been able to understand even the concept of light.

In early 1973, Vicki, then 22, was working as an occasional singer in a nightclub in Seattle. One night, at closing time, she was unable to call for a taxi to drive her home and circumstances forced her to take the only other option: a ride with a couple of inebriated patrons. Not surprisingly, a serious accident ensued during which Vicki was thrown out of their van. Her injuries were extensive and life-threatening, and included a skull fracture and concussion, and damage to her neck, back, and one leg. In fact, it took her a full year after being released from the hospital before she could stand upright without the risk of fainting.

She has no memory of the her trip to Harborview Hospital in the ambulance, but after she arrived at the emergency room, she came again to awareness when she found herself up on the ceiling watching a male doctor and a woman—she is not sure whether the woman was another physician or a nurse—working on her body. She could overhear their conversation, too, which had to do with their fear that because of possible damage to Vicki's eardrum, she could become deaf as well as blind. Vicki tried desperately to communicate to them that she was fine, but naturally drew no response. She was also aware of seeing her body below her, which she recognized by certain identifying features, such as a distinctive wedding ring she was wearing. According to her testimony, Vicki first had a very fleeting image of herself lying on the metal table and she was sure, she said, that "it was me," although it took her a moment to register that fact with certainty. As she later told us:

I knew it was me. ... I was pretty thin then. I was quite tall and thin at that point. And I recognized at first that it was a body, but I didn't even know that it was mine initially. Then I perceived that I was up on the ceiling, and I thought, "Well, that's kind of weird. What am I doing up here?" I thought, "Well, this must be me. Am I dead?. ..." I just briefly saw this body, and ... I knew that it was mine because I wasn't in mine. Then I was just away from it. It was that quick.

Almost immediately after that, as she recalls, she found herself going up through the ceilings of the hospital until she was above the
roof of the building itself, during which time she had a brief panoramic view of her surroundings. 

A second case is that of Brad Barrows, a 33-year-old man living in Connecticut, who had a near-death experience in the winter of 1968 when he was only 8 years old. At the time, he was a student at the Boston Center for Blind Children, and had contracted a severe case of pneumonia and eventually had severe breathing difficulties. Afterward, he was told by nurses that his heart had stopped, apparently for at least four minutes, and that cardiopulmonary resuscitation (CPR) had been necessary to bring him back. Brad remembers that when he couldn't breathe any longer, he felt himself lifting up from the bed and floating through the room toward the ceiling. He saw his apparently lifeless body on the bed. He also saw his blind roommate get up from his bed and leave the room to get help. (His roommate later confirmed this.) Brad then found himself rapidly going upward through the ceilings of the building until he was above the roof. At this point, he found that he could see clearly.

He estimates that it was between 6:30 and 7:00 in the morning when this happened. He noticed that the sky was cloudy and dark. There had been a snowstorm the day before, and Brad could see snow everywhere except for the streets, which had been plowed, though they were still slushy. He was able to give us a very detailed description of the way the snow looked. Brad could also see the snowbanks that the plows had created. He saw a street car go by. Finally, he recognized a playground used by the children of his school and a particular hill he used to climb nearby. When asked if he "knew" or "saw" these things, he said: "I clearly visualized them. I could suddenly notice them and see them. ... I remember . . . being able to see quite clearly."

Sometimes the initial onset of visual perception of the physical world is disorienting and even disturbing to the blind. This was true for Vicki, for example, who said:

I had a hard time relating to it [i.e., seeing]. I had a real difficult time relating to it because I've never experienced it. And it was something very foreign to me. . . . Let's see, how can I put it into words? It was like hearing words and not being able to understand them, but knowing that they were words. And before you'd never heard anything. But it was something new, something you'd not been able to previously attach any meaning to.

Later, in commenting on the shock of these initial visual impressions, she even used the word "frightening" to characterize them. She also told us that she was never able to discriminate colors as such, but only "different shades of brightness," about which impressions she could only wonder afterward whether they represented what sighted people meant by color.

One fairly obvious possibility that has often been advanced in connection with the NDEs and OBEs of sighted persons is that this experience is some kind of a dream, perhaps a lucid or exceptionally vivid dream, which has such realistic properties that it is easily misinterpreted and thus given an ontological status it does not deserve. To evaluate this hypothesis, we first need to inquire into what is known about normal oneiric processes in the blind. Fortunately, there has been a great deal of research devoted to the dreams of the blind, some of it going back more than a hundred years. As a result of these investigations, certain generalizations about the presence of visual imagery in dreams appear to stand up quite well. Among these "empirical cornerstones" (Kirtley, 1975) are that (1) there are no visual images in the dreams of the congenitally blind.

In our interviews, we routinely asked our respondents about the nature of their dreams, and what we found in our sample accords with the generalizations just described. In addition, however, and particularly pertinent to the hypothesis under consideration, our respondents usually went on to say that not only were their NDEs unlike their usual dreams, but in the case of those blind from birth, they stood out as radically different precisely because they contained visual imagery, whereas their dreams had always lacked this element. Vicki, one of our NDErs blind from birth, provides a good case in point:

Interviewer. How would you compare your dreams to your NDEs?
Vkki: No similarity, no similarity at all. Interviewer: Do you have any kind of visual perception in your
dreams?
Vicki: Nothing. No color, no sight of any sort, no shadows, no light, no nothing. 
Interviewer: What kinds of perceptions are you aware of in your typical dreams?
Vicki: Taste—I have a lot of eating dreams [laughs]. And I have dreams when I'm playing the piano and singing, which I do for a living, anyway. I have dreams in which I touch things. ... I taste things, touch things, hear things, and smell things—that's it. 
Interviewer: And no visual perceptions?
Vicki: No. 
Interviewer: So that what you experienced during your NDE was quite different from your dreams?
Vicki: Yeah, because there's no visual impression at all in any dream that I have.

These remarks, along with similar asseverations from other participants in our study, make it abundantly clear that from our respondents' point of view, the NDE, especially its visual aspect, has nothing in common with their usual dreams. It is instead something in a class by itself and not to be conflated with dreams. Since there is no support whatever from our interviews for the dream hypothesis of NDEs, we may confidently reject it as a potential explanation for our findings.

Is it possible, then, that what our respondents report is actually a form of blindsight? Further scrutiny of the results of research into blindsight shows very quickly that although it seems to be a legitimate form of perception, it can by no means account for our findings. First of all, patients manifesting the effect typically cannot verbally describe the object they are alleged to see, unlike our respondents who, as we have noted, were usually certain about what they saw and could describe it often without hesitation. In fact, a cortically blind patient, even when his or her object identification exceeds chance levels, believes that it is largely the result of pure guesswork. 

Kenneth Ring & Sharon Cooper, "Near-death and Out-of-Body Experience In the Blind: A Study of Apparent Eyeless Vision" Journal of Near-Death Studies 16/2 (December, 1997), 101-147.

The same article gives examples of veridical NDEs and OBEs of people who weren't born blind, but nevertheless were blind at the time of the reported experience, and describe seeing things which were corroborated by witnesses. You can read it for yourself:

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