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Thursday, June 30
Evolution 2011: The Altruism-Fest, part two
One of the most popular of the participants in the Evolution 2011 meetings at Norman, Oklahoma was not even a human. She was a killdeer.
Killdeer are plovers (birds) whose nests are simple depressions on the ground. Their eggs are spotted, and the mothers choose splotchy-colored brownish places to lay their eggs (see photograph). Killdeer have been extremely successful, and are found along the edges of parking lots over much of North America. You have probably seen them, running along very fast, with white fronts and two black bars on their breasts, and calling out “killdeer, killdeer.”
A mother killdeer made her nest in the mulch near the parking lot at the convention center where Evolution 2011 took place. I parked my car right next to it a few times. When a human first approaches, the mother killdeer starts calling, then spreads her wings to threaten the intruder (see photograph). Then she runs off a few meters away, falls on her side, and exposes inner feathers in such a way that she appears to be injured. This behavior may draw the attention of the intruder away from the nest and toward the mother bird, who is pretending to be an easy piece of meat to catch. If the intruder approaches her, she runs off a little further and repeats the process.
As the mother killdeer was putting on her show and making a lot of noise, right as many attendees were leaving for lunch, a little crowd gathered around my car to watch and marvel. They were marveling at one of the most interesting examples of altruism.
The mother bird is putting her life at risk to protect her eggs. But it is worth the risk, because when the little birds hatch, they will carry many of her genes into the next generation. The evolutionary principles—kin selection and inclusive fitness—are east to understand, but always marvelous to behold.
I am the author of Life of Earth: Portrait of a Beautiful, Middle-Aged, Stressed-Out World, recently published by Prometheus Books. See my website for more information.
Sunday, June 26
Evolution 2011: The Altruism-Fest, part one
I recently returned from the Evolution 2011 meetings in Norman, Oklahoma. I previously described the excitement of learning about new research into evolutionary science. I now want to analyze the meeting as an example of altruism.
The papers and posters that were presented at the meeting were important, but the information in these presentations can be obtained from journals and online sources. There is no need for scientists and students to gather from all over the world just to get information. What is most important at meetings such as this is that evolutionary scientists get together to discuss one another’s work and benefit from one another’s criticism and encouragement.
In some meetings, scientists like to criticize one another’s papers; in particular, they like to criticize the papers presented by grad students and postdocs of their rivals. My sense is that this has become less common in recent years, and I saw none of it at the Evolution 2011 meetings. The entire atmosphere was encouragement and dialogue. I did not witness any verbal attacks, even when some of the presentations were clearly amateurish projects. Those projects will never get published, but we all considered it important to encourage the young investigators who did them. I think it is safe to say that all of the young graduate (and undergraduate) students who presented their work went away with encouragement for their dedication and intelligence. I made a special effort to praise instances of particularly good work by graduate students.
In other words, Evolution 2011 was not so much a gathering of competitors as it was an altruism-fest. Altruism is when animals do nice things for other animals in the same species, and benefit as a result of it. An altruism-fest is quite different from what critics of evolution might expect an evolution meeting to be. Creationist critics consider evolution to result from bloody fights and the law of the jungle, and they openly declare (as I showed in my March blog entries) that evolution leads to slavery and holocaust. If you can judge people by what they do more than by what they say, then it is clear that altruism is a prominent feature of modern evolutionary science. Evolutionary scientists freely share ideas, and develop bonds of friendship, even when these bonds offer no immediate promise of reciprocal benefit.
Of course, it was not all altruism. It was also a chance for graduate students to increase their visibility in the job market. All of the presentations used PowerPoint and most of them had clever illustrations that made their main points easily understandable. Many were humorous and many had imbedded video footage. The sessions functioned like leks, which are gatherings of male animals showing off while females walk around and check them out. Only in this case, the showing off was not reproductive but intellectual, and the presenters and observers were equally men and women. I do not get the sense that evolutionary biology has very much male bias anymore.
Not only is evolutionary science alive and well, but so is altruism. And where do you find it? As much at a meeting of evolutionary scientists as at a meeting of preachers, perhaps more so; and certainly more than at a meeting of businessmen and women or diplomats.
I did not stay for the banquet. Altruistically, I gave away my banquet ticket to a postdoc from Siberia. I expected nothing in return, but I believe I live in a better world in which I contribute to the general ocean of altruism. While everyone else was having their banquet in Norman, I was eating breaded frog legs at a Chinese buffet in Okmulgee. Frog legs at a Chinese buffet? Only in Oklahoma.
And, as described in the next blog entry, not all of the altruism at these meetings was human.
I am the author of Life of Earth: Portrait of a Beautiful, Middle-Aged, Stressed-Out World, recently published by Prometheus Books. See my website for more information.
The papers and posters that were presented at the meeting were important, but the information in these presentations can be obtained from journals and online sources. There is no need for scientists and students to gather from all over the world just to get information. What is most important at meetings such as this is that evolutionary scientists get together to discuss one another’s work and benefit from one another’s criticism and encouragement.
In some meetings, scientists like to criticize one another’s papers; in particular, they like to criticize the papers presented by grad students and postdocs of their rivals. My sense is that this has become less common in recent years, and I saw none of it at the Evolution 2011 meetings. The entire atmosphere was encouragement and dialogue. I did not witness any verbal attacks, even when some of the presentations were clearly amateurish projects. Those projects will never get published, but we all considered it important to encourage the young investigators who did them. I think it is safe to say that all of the young graduate (and undergraduate) students who presented their work went away with encouragement for their dedication and intelligence. I made a special effort to praise instances of particularly good work by graduate students.
In other words, Evolution 2011 was not so much a gathering of competitors as it was an altruism-fest. Altruism is when animals do nice things for other animals in the same species, and benefit as a result of it. An altruism-fest is quite different from what critics of evolution might expect an evolution meeting to be. Creationist critics consider evolution to result from bloody fights and the law of the jungle, and they openly declare (as I showed in my March blog entries) that evolution leads to slavery and holocaust. If you can judge people by what they do more than by what they say, then it is clear that altruism is a prominent feature of modern evolutionary science. Evolutionary scientists freely share ideas, and develop bonds of friendship, even when these bonds offer no immediate promise of reciprocal benefit.
Of course, it was not all altruism. It was also a chance for graduate students to increase their visibility in the job market. All of the presentations used PowerPoint and most of them had clever illustrations that made their main points easily understandable. Many were humorous and many had imbedded video footage. The sessions functioned like leks, which are gatherings of male animals showing off while females walk around and check them out. Only in this case, the showing off was not reproductive but intellectual, and the presenters and observers were equally men and women. I do not get the sense that evolutionary biology has very much male bias anymore.
Not only is evolutionary science alive and well, but so is altruism. And where do you find it? As much at a meeting of evolutionary scientists as at a meeting of preachers, perhaps more so; and certainly more than at a meeting of businessmen and women or diplomats.
I did not stay for the banquet. Altruistically, I gave away my banquet ticket to a postdoc from Siberia. I expected nothing in return, but I believe I live in a better world in which I contribute to the general ocean of altruism. While everyone else was having their banquet in Norman, I was eating breaded frog legs at a Chinese buffet in Okmulgee. Frog legs at a Chinese buffet? Only in Oklahoma.
And, as described in the next blog entry, not all of the altruism at these meetings was human.
I am the author of Life of Earth: Portrait of a Beautiful, Middle-Aged, Stressed-Out World, recently published by Prometheus Books. See my website for more information.
Wednesday, June 22
Evolution 2011: Evolution is Alive and Well
I have just returned from the Evolution 2011 meetings in Norman, Oklahoma. This is the pre-eminent meeting of evolutionary scientists in the world, sponsored by the Society for the Study of Evolution, the American Society of Naturalists, and the Society for Systematic Biology. Anyone who thinks that evolutionary science is based on very little evidence should experience the flood of data reported at the Evolution meetings every year. All over the world and in every group of organisms, the evidence continues to pour in that evolution is occurring all around us and has been occurring for billions of years. Those of us who have been around longer took special effort to encourage the graduate students and postdocs who have done amazing and creative research.
I will briefly mention three of the graduate student papers that I found particularly interesting.
Sarah Ann Bodbyl Roels (University of Kansas) conducted an experiment in which bees selected floral traits in a monkeyflower species for several generations. Both the treatment and control were inside of identical greenhouses, with the bumblebee hive inside one of the greenhouses. This is a particularly good example of experimental design.
Carolina Bonin (Scripps Institute, La Jolla) obtained DNA samples from seals near Antarctica to determine patterns of paternity in a population that had been driven nearly to extinction. Getting DNA from a male seal is not an easy task; you have to run up with a sample vial on a pole, poke the male to get a blood sample, and run like hell as the male flops along after you. Impressive work.
I was most impressed with the work of Kelsey Byers (University of Washington), who has figured out which chemicals stimulate the bumblebees that pollinate monkeyflowers. She did this by inserting electrodes into the exposed brains of bumblebees, and measuring electrical stimulation in response to different volatile chemical components of nectar. This is a very creative approach to the study of pollination.
The meeting was also an opportunity for people from all over the world to talk about what is happening on the creation/evolution front. Oklahoma is perhaps the world epicenter of creationism, and visitors from other countries wanted to know what is going on here. In the photograph, Vic Hutchison (the grand old man of evolution education in Oklahoma) talked with foreign students Bjorn Ostman (originally from Denmark) and Olga Dolgova (originally from Vladivostok, Siberia) about the evolutionary political scene in America.
Organizing this meeting and making sure that everything happened on time for the hundreds of participants was a big job, and I want to thank Rich Broughton, Larry Weider, and Ingo Schlupp, all faculty members at the University of Oklahoma, for their amazing work in making this meeting a success.
I will post two more entries about the Evolution 2011 meetings.
I am the author of Life of Earth: Portrait of a Beautiful, Middle-Aged, Stressed-Out World, recently published by Prometheus Books. See my website for more information.
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Friday, June 17
Critical Examination of the Near Death Experience, Part Four. How could Near Death Experiences Have Evolved?
As I established in previous blog entries, the Near Death Experience (NDE) is no mere delusion. But neither is it a glimpse into Heaven. It is entirely subjective, occurring within the brain of the person experiencing it. It is a highly structured, detailed, and intense subjective experience. It is something that the brain does in extremis, that is, when imminently threatened with death.
This immediately raises the question of how the capacity for humans to have such a highly structured set of brain experiences could have evolved. Natural selection cannot, after all, favor something that occurs just before death, since the person who experiences them cannot leave offspring.
I wish to suggest that the Near Death Experience evolved because it offered a fitness advantage to people who experienced them and then returned to life. Consider what would have happened back in cave man days. A warrior was killed. Then he came back to life! And he had such things to report! Such visions! Clearly, he had some special contact with the gods. He would be rewarded with high social status and all of the additional mating opportunities that this would afford. Something similar could have happened to any shaman, male or female, who might have gone a little bit too far with the Salvia divinorum or the mushrooms.
Someone who had mere delusions from a brush with death would not be nearly as credible as one who had specific and credible visions such as those associated with the Near Death Experience—credible enough that people still believe them, and books about them are best sellers even in an age of science.
It has been noted that people from many different cultures have similar near death experiences. While it is possible that this is because they have all seen Oprah, it could also be because the brain-based capacity for experiencing a near-death experience had already evolved before the common ancestral populations of all modern races left Africa about 100,000 years ago, before modern races had differentiated.
I have, therefore, offered in this series of blog entries first a medical then an evolutionary explanation for the Near Death Experience. It is neither mere delusion, as skeptics often claim, nor is it a glimpse into heaven.
This immediately raises the question of how the capacity for humans to have such a highly structured set of brain experiences could have evolved. Natural selection cannot, after all, favor something that occurs just before death, since the person who experiences them cannot leave offspring.
I wish to suggest that the Near Death Experience evolved because it offered a fitness advantage to people who experienced them and then returned to life. Consider what would have happened back in cave man days. A warrior was killed. Then he came back to life! And he had such things to report! Such visions! Clearly, he had some special contact with the gods. He would be rewarded with high social status and all of the additional mating opportunities that this would afford. Something similar could have happened to any shaman, male or female, who might have gone a little bit too far with the Salvia divinorum or the mushrooms.
Someone who had mere delusions from a brush with death would not be nearly as credible as one who had specific and credible visions such as those associated with the Near Death Experience—credible enough that people still believe them, and books about them are best sellers even in an age of science.
It has been noted that people from many different cultures have similar near death experiences. While it is possible that this is because they have all seen Oprah, it could also be because the brain-based capacity for experiencing a near-death experience had already evolved before the common ancestral populations of all modern races left Africa about 100,000 years ago, before modern races had differentiated.
I have, therefore, offered in this series of blog entries first a medical then an evolutionary explanation for the Near Death Experience. It is neither mere delusion, as skeptics often claim, nor is it a glimpse into heaven.
Friday, June 10
Critical Examination of the Near Death Experience, Part Three
This is the third essay in a series that examines evidence presented by Jeffrey Long and Paul Perry which, they claim, prove that the Near Death Experience (NDE) is an actual vision of the afterlife. In the previous essays, I explain that, while the NDE may contain information that the subject has picked up from his or her environment in some way not yet understood, the NDE itself is a subjective experience.
The authors make the claim that victims or patients that experience NDEs could not have been having a subjective brain experience, because these people were in fact brain-dead at the time that they had the experiences; that is, they were EEG (electroencephalogram) flat-liners. As they write on page 46, “It is medically inexplicable to have a highly organized and lucid experience while unconscious or clinically dead.” Now, if the people who had NDEs were brain dead at the time, then there is no other explanation than that given by the authors: that the people’s spirits had in fact left their bodies and begun their trip to heaven. This is because nerve cells produce electrical and magnetic fields. If the nerve cells were operating at all, delusionally or otherwise, they would have produced some trace on the EEG. Moreover, the authors are very inconsistent on this point. An entire chapter, chapter 4, is about visions that people have had during anesthesia. People are not brain dead during anesthesia. So is NDE something that happens when the spirit leaves the body, or isn’t it? Did my spirit leave my body when I was last under anesthesia?
But the authors have no direct proof that the subjects were brain dead while having their NDEs. The authors have relied upon stories submitted to their online website. Although I agree with the authors that the contributors were seldom if ever actually lying, we simply do not have medical corroboration for the claim that they had NDE during actual clinical death. It is possible that the victims were brain dead for a while, but they may have experienced their NDE either just before or just after their brain-dead period, at a time when they might have been capable of perceiving the things that they later reported.
I would also like to point out that, as I mentioned in the first essay, Persinger’s God Helmet and the drug ketamine produce some of the same mental images as those that appear in NDEs. Of course, NDEs are much clearer and more detailed than those that emerge from God Helmet and ketamine experiences. But this is not surprising, since the God Helmet and ketamine may only partially stimulate whatever brain circuits may be involved in the NDE.
The authors are correct in asserting that an NDE is no ordinary mental experience. They invite you to try closing your eyes and then describing the experiences around you. You cannot do it, even if you are alert, so you could not do so when you are in or in a coma. This is a good point. But the brain, when it experiences an NDE brain, is in extremis, which is a condition you cannot simulate. The mind might become hyper-aware as its last gasp before dying. Warriors sometimes enter an altered mental state when they are in the middle of a battle, one in which time seems to slow down and in which they do crazy things that actually work. The Viking word for such a warrior was “berserker.” It is an altered mental state that occurs under extreme conditions. Maybe the NDE is such a state also.
I would like to offer a possible explanation for the Near Death Experience. This hypothesis is not proven but will explain the phenomena outlined in Long and Perry’s book and in these blog entries.
• First, the patients experienced dreams or received sensations from around them just before clinical death. These sensations were time-distorted, with the result that they seemed to occur throughout the period of death.
• Second, when the patients entered clinical death, electrical imbalances were maintained in the brain, even though there were no impulses traveling along the neurons.
• Third, when the patients were revived, they remembered the things that happened in their brains just before the period of death, which were preserved in the electrical imbalances. This hypothesis would explain how the patients could experience NDEs without actually processing any new experience while they were clinically dead (with flatlined EEGs).
You are particularly encouraged to make comments on this hypothesis.
One important question remains. The NDE is a detailed mental experience that cannot be simply a delusion. It therefore must have evolved. I will approach this question in the next entry.
The authors make the claim that victims or patients that experience NDEs could not have been having a subjective brain experience, because these people were in fact brain-dead at the time that they had the experiences; that is, they were EEG (electroencephalogram) flat-liners. As they write on page 46, “It is medically inexplicable to have a highly organized and lucid experience while unconscious or clinically dead.” Now, if the people who had NDEs were brain dead at the time, then there is no other explanation than that given by the authors: that the people’s spirits had in fact left their bodies and begun their trip to heaven. This is because nerve cells produce electrical and magnetic fields. If the nerve cells were operating at all, delusionally or otherwise, they would have produced some trace on the EEG. Moreover, the authors are very inconsistent on this point. An entire chapter, chapter 4, is about visions that people have had during anesthesia. People are not brain dead during anesthesia. So is NDE something that happens when the spirit leaves the body, or isn’t it? Did my spirit leave my body when I was last under anesthesia?
But the authors have no direct proof that the subjects were brain dead while having their NDEs. The authors have relied upon stories submitted to their online website. Although I agree with the authors that the contributors were seldom if ever actually lying, we simply do not have medical corroboration for the claim that they had NDE during actual clinical death. It is possible that the victims were brain dead for a while, but they may have experienced their NDE either just before or just after their brain-dead period, at a time when they might have been capable of perceiving the things that they later reported.
I would also like to point out that, as I mentioned in the first essay, Persinger’s God Helmet and the drug ketamine produce some of the same mental images as those that appear in NDEs. Of course, NDEs are much clearer and more detailed than those that emerge from God Helmet and ketamine experiences. But this is not surprising, since the God Helmet and ketamine may only partially stimulate whatever brain circuits may be involved in the NDE.
The authors are correct in asserting that an NDE is no ordinary mental experience. They invite you to try closing your eyes and then describing the experiences around you. You cannot do it, even if you are alert, so you could not do so when you are in or in a coma. This is a good point. But the brain, when it experiences an NDE brain, is in extremis, which is a condition you cannot simulate. The mind might become hyper-aware as its last gasp before dying. Warriors sometimes enter an altered mental state when they are in the middle of a battle, one in which time seems to slow down and in which they do crazy things that actually work. The Viking word for such a warrior was “berserker.” It is an altered mental state that occurs under extreme conditions. Maybe the NDE is such a state also.
I would like to offer a possible explanation for the Near Death Experience. This hypothesis is not proven but will explain the phenomena outlined in Long and Perry’s book and in these blog entries.
• First, the patients experienced dreams or received sensations from around them just before clinical death. These sensations were time-distorted, with the result that they seemed to occur throughout the period of death.
• Second, when the patients entered clinical death, electrical imbalances were maintained in the brain, even though there were no impulses traveling along the neurons.
• Third, when the patients were revived, they remembered the things that happened in their brains just before the period of death, which were preserved in the electrical imbalances. This hypothesis would explain how the patients could experience NDEs without actually processing any new experience while they were clinically dead (with flatlined EEGs).
You are particularly encouraged to make comments on this hypothesis.
One important question remains. The NDE is a detailed mental experience that cannot be simply a delusion. It therefore must have evolved. I will approach this question in the next entry.
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Thursday, June 2
Critical Examination of the Near Death Experience, Part Two
This is the second essay in a series that examines evidence presented by Jeffrey Long and Paul Perry which, they claim, prove that the Near Death Experience (NDE) is an actual vision of the afterlife. In the previous essay, I interpreted the evidence to indicate that people who experience NDEs are in fact perceiving something, but not the afterlife; they are perceiving, in some way not yet understood, their immediate environment. But there are several reasons to believe that the NDE is a subjective experience inside of the brain. This does not mean that it is a mere delusion or dream. It is clearly a unique kind of experience.
But it is probably subjective. Here are some reasons.
First, not everyone has the same visions. This is hardly surprising for a subjective experience, but cannot be true of someone actually looking into the afterlife, unless, that is, each of us has our own private heaven waiting for us. The authors say that nearly all people who have an NDE report intense joy. Only about one-third report the tunnel, and two-thirds report the bright light. Fewer than one in four reports the stereotypical life-review (see previous essay). And I suspect that there may be even more diversity of experience than the authors report. Long and Perry say that NDEs are blissful experiences, but I remember reading somewhere that a small but significant percentage of people have what they think is an encounter with Hell. The authors, moreover, report a woman who heard, in her NDE, the universe saying Allah ho akbar! Really? Is the afterlife a Muslim one? Obviously, if there is an afterlife, it was experienced as such—and experienced subjectively—by this Muslim woman. Finally, most NDE reports include an altered sense of time. This is a trick that our brains play on us all the time, for example in dreams that seem to last for a long time but which had to occur during a brief minute or so of rapid eye movement.
Second, suppose that we do in fact have our own private heavens waiting for us. If this is the case, then the people in the NDE visions cannot be actual people. How can Granny actually be existing within MY private heaven? Doesn’t she have her own heaven to live in and experience? Why should my dead relatives be sitting around waiting for me to go rocketing up through the tunnel of light? One person reported having seen her grandmother back in the house in which she lived before her death (Chapter 4). How likely is it that her dead grandmother in heaven lived in a house exactly like the one she had on Earth?
The kind of subjectivity experienced during an NDE is probably not a mere cultural phenomenon. Some careless critics dismiss NDEs as the “Oprah effect,” in which people are very likely to report their NDE in terms that they have learned from watching Oprah’s frequent coverage of this phenomenon. This may sometimes occur. A person who experiences an NDE, one that consists of vague sensations, may subsequently interpret these sensations in terms of a life review, tunnel, loved ones, etc., based on what they have seen on television or read in books. The authors claim that since many of the components of an NDE are the same in people from many different cultures proves that it is not something upon which they have imposed their own interpretations. The problem with this claim is that many different cultures have seen western television. The authors point out, however, that NDEs reported from before 1975, when Raymond Moody wrote the first thorough book on the subject (Life after Life), are essentially the same as those reported in the post-Oprah era. But the fact that people who have NDEs are not merely repeating what they have heard on Oprah’s show does not prove that they are really seeing into the afterlife.
I believe the evidence demonstrates that the NDE is a subjective experience—a very unique one, and which may incorporate information from sensory modalities we do not yet understand. At the very least, if they are seeing into the afterlife, each person is seeing it in his or her own way. Still, there remain some unexplained questions, which I will address in upcoming essays.
But it is probably subjective. Here are some reasons.
First, not everyone has the same visions. This is hardly surprising for a subjective experience, but cannot be true of someone actually looking into the afterlife, unless, that is, each of us has our own private heaven waiting for us. The authors say that nearly all people who have an NDE report intense joy. Only about one-third report the tunnel, and two-thirds report the bright light. Fewer than one in four reports the stereotypical life-review (see previous essay). And I suspect that there may be even more diversity of experience than the authors report. Long and Perry say that NDEs are blissful experiences, but I remember reading somewhere that a small but significant percentage of people have what they think is an encounter with Hell. The authors, moreover, report a woman who heard, in her NDE, the universe saying Allah ho akbar! Really? Is the afterlife a Muslim one? Obviously, if there is an afterlife, it was experienced as such—and experienced subjectively—by this Muslim woman. Finally, most NDE reports include an altered sense of time. This is a trick that our brains play on us all the time, for example in dreams that seem to last for a long time but which had to occur during a brief minute or so of rapid eye movement.
Second, suppose that we do in fact have our own private heavens waiting for us. If this is the case, then the people in the NDE visions cannot be actual people. How can Granny actually be existing within MY private heaven? Doesn’t she have her own heaven to live in and experience? Why should my dead relatives be sitting around waiting for me to go rocketing up through the tunnel of light? One person reported having seen her grandmother back in the house in which she lived before her death (Chapter 4). How likely is it that her dead grandmother in heaven lived in a house exactly like the one she had on Earth?
The kind of subjectivity experienced during an NDE is probably not a mere cultural phenomenon. Some careless critics dismiss NDEs as the “Oprah effect,” in which people are very likely to report their NDE in terms that they have learned from watching Oprah’s frequent coverage of this phenomenon. This may sometimes occur. A person who experiences an NDE, one that consists of vague sensations, may subsequently interpret these sensations in terms of a life review, tunnel, loved ones, etc., based on what they have seen on television or read in books. The authors claim that since many of the components of an NDE are the same in people from many different cultures proves that it is not something upon which they have imposed their own interpretations. The problem with this claim is that many different cultures have seen western television. The authors point out, however, that NDEs reported from before 1975, when Raymond Moody wrote the first thorough book on the subject (Life after Life), are essentially the same as those reported in the post-Oprah era. But the fact that people who have NDEs are not merely repeating what they have heard on Oprah’s show does not prove that they are really seeing into the afterlife.
I believe the evidence demonstrates that the NDE is a subjective experience—a very unique one, and which may incorporate information from sensory modalities we do not yet understand. At the very least, if they are seeing into the afterlife, each person is seeing it in his or her own way. Still, there remain some unexplained questions, which I will address in upcoming essays.