Neurologist and University of Toledo Neuroscience Researcher, Dr. John Greenfield considers the EEG data from patients with near death experience (NDE).
For near death experience skeptics, medical evidence of a flat EEG during an out of body experience has always been a stumbling block. After all, a brain dead patient can’t hallucinate. But, does a flat EEG really mean no brain activity? NDE doubters have claimed activity deep inside the brain, beyond the reach of EEG instruments, must account for the complex “realer than real” experiences reported by those who briefly pass into the afterlife. Now, University of Toledo Neuroscience researcher, and EEG expert, Dr. John Greenfield explains why this claim doesn’t hold up.
“It’s very unlikely that a hypoperfused brain [someone with no blood flow to the brain], with no evidence of electrical activity could generate NDEs. Human studies as well as animal studies have typically shown very little brain perfusion [blood flow] or glucose utilization when the EEG is flat. There are deep brain areas involved in generating memories that might still operate at some very reduced level during cardiac arrest, but of course any subcortically generated activity can’t be brought to consciousness without at least one functioning cerebral hemisphere. So even if there were some way that NDEs were generated during the hypoxic state [while the brain is shut off from oxygen], you would not experience them until reperfusion [blood flow] allowed you to dream them or wake up and talk about them”, Greenfield stated.
NDE Researcher, Dr. Penny Sartori, examines memories of resuscitation by patients suffering cardiac arrest.
With near death experience cases making there way into the, New England Journal of Medicine, Journal of Psychiatry, and other major medical journals, NDE doubters have looked to the timing of patient memories as a way of explaining this unexplainable phenomena. If memories of out of body travel, and all embracing love occur after ones brush with death, NDEs may still fit within our medical science worldview.
The timing of NDE memories is the research question Dr. Penny Sartori sought to answer, “I worked in the intensive care unit and because of the nature of my job, of course, I’d come across a lot of death. And of course makes you wonder what happens when we die. For five years I gathered data, where I spoke to patients in the intensive care unit and particularly patients who’d had a cardiac arrest. When these patients revived, as soon as they were medically fit, I approached them and asked the simple question, ‘Did you have any memory of the time that you were unconscious?'”
“For the people who had a near-death experience and out of body experience [their recollection of resuscitation] was really quite accurate and I decided then to ask the control group, the people who’d had a cardiac arrest but had no recollection of anything at all. I asked them if they would reenact their resuscitation scenario and tell me what they thought that we had done to resuscitate them. And what I found is that many of the patients couldn’t even guess as to what we’d done. They had no idea at all. And then some of them did make guesses, but these were based on TV hospital dramas that they’d seen. I found that what they reported was widely inaccurate. So there was a stark contrast really in the very accurate out of body experiences reported and then the guesses that the control group had made.”, Dr. Sartori reported.
While research like this may never be enough to convince dogmatic skeptics, the medical evidence for near death experience continues to challenge us to reexamine our beliefs about what lies beyond death.
Play it:[audio: http://media.blubrry.com/skeptiko/content.blubrry.com/skeptiko/skeptiko-90-Penny-Sartori.mp3]
Alex Tsakiris: Welcome to Skeptiko, where we explore controversial science with leading researchers, thinkers, and their critics. I’m your host, Alex Tsakiris, and I want to start by thanking those of you who’ve contacted me directly since the last episode of Skeptiko and have joined me on Facebook or joined me on Twitter. It’s been great to get to know you, to dialogue a little bit, and I hope we can keep that going.
So any of you who are interested in connecting with the show, connecting with me, please feel free, drop me a note either by e-mail – many of you did that – or Facebook, Twitter, follow me on Twitter, whatever you like. Let’s try and further this effort of really building a community of folk who are interested in approaching these topics we cover on Skeptiko in an open-minded way that is critical of both bunky science as well as bunky skeptics because that’s really our agenda here.
But let’s get on to today’s episode because today we have two very interesting interviews that address the near-death experience topic. We’re going to dig into a couple issues that have been coming up in the previous episodes of Skeptiko.
Now as a little bit of a background, if you wind up talking about near-death experience with any well-informed skeptics, your dialogue is likely to go in a couple of directions. First, any well-informed skeptic is going to acknowledge the existence of the near-death experience phenomena. At this point, case studies have been published in the New England Journal of Medicine, Journal of Psychiatry, just about every major medical journal. So there’s no getting around the phenomena. What well-informed skeptics will focus on, instead, are two issues.
The first centers around the issue of whether the near-death experiencer really is brain dead. So for example, on the last episode of Skeptiko you heard from Dr. Michael Persinger and he made a claim that I’ve heard several times before, and it seemed very absurd to me, but a lot of folks wanted me to pursue it, so I did.
And that’s the claim that even though someone may be presenting a flat EEG they still may be having a near-death experience, a complex, coherent dream-like hallucination, but it just isn’t showing up on their EEG. Now again, I think that idea is way out there, but we’re going to have a guest come on and address that issue a little bit.
Now the second point that your well-informed skeptic is likely to make about near-death experience is the timing issue. So they’re likely to kind of postulate that maybe they’re having this near-death experience when their brain was back online and they’re just remembering it and they’re thinking it happened when they were brain dead, but it really didn’t happen that way. And for that I have a very interesting interview with Dr. Penny Sartori, who’s done some very, very interesting research that I’ve referenced before but never really had a chance to talk with her directly. So we’ll hear from her.
But first, let’s get to this short interview I did with a Professor of Neurology at the University of Toledo, a very highly-regarded guy, Dr. John Greenfield.
I’m fortunate enough to have on the phone Dr. John Greenfield from the University of Toledo, who is the author of Reading EEGs, A Practical Approach, and he has a list of qualifications about as long as my arm, as they say. So I’m going to ask Dr. Greenfield to tell us a little bit about your background, what you do there at the University of Toledo, and your qualifications in terms of addressing questions about EEG use.
Dr. John Greenfield: Okay, again, my name is John Greenfield. I’m a Professor of Neurology at the University of Toledo, College of Medicine. I have trained in both neurology and clinical neurophysiology and EEG, so I’m board certified in reading EEGs. So I suppose that’s my qualification.
Alex Tsakiris: Great. I contacted you because as folks who listen to this show regularly know, we’ve been kind of delving into EEGs because they crop up when we start looking at near-death experience and possible explanations for what’s going on in someone’s brain. So what I really wanted to focus on, and you provided a great insight in your e-mail, is this question of whether it’s likely that a near-death experiencer is having a complex near-death experience, as it’s described, without anything showing up on their EEG.
Dr. John Greenfield: Well, as I mentioned to you before, I think the likelihood of that is pretty low. Most patients, when the EEG is flat, when it’s not showing any activity, that really suggests that the brain is not doing very much. The likelihood of having any sort of experiences at all in that setting is pretty low.
Alex Tsakiris: You referenced in your e-mail to me, you said, “It’s very unlikely that a hypo-profused brain with no evidence…”
Dr. John Greenfield: Right. So when the brain is not getting much blood, it pretty much shuts down. And whether that ends up being permanent depends on how long the blood flow is shut off. But in that time when it’s not getting very much, there’s really very little activity going on and it would be very unlikely that somebody could have a complex sort of dream-like state as described for most near-death experiences, at least during that time.
Alex Tsakiris: Right. And you kind of alluded to both human studies and I was alluding to animal studies that would back up that conclusion. Is that right? Do you want to elaborate on that at all?
Dr. John Greenfield: Well, so there are a few studies. There’s not much really published on this very much but when we suspect that patients may be brain dead or very near brain death and they have flat EEGs, often we’ve done studies to look at blood flow to the brain or glucose utilization in the brain. There are a few radio isotope kind of tracer studies that let you look at those questions and very often they show very little brain activity. So a flat EEG typically correlates with a very inactive brain.
Alex Tsakiris: Great. That’s exactly what we were kind of driving at, so thanks again for joining us today on Skeptiko for this short little interview. And for those folks who are interested more in this topic, would the book that you’ve published, Reading EEGs, I take it that’s more of a technical manual for neurologists?
Dr. John Greenfield: It’s really an introduction for neurologists and EEG fellows and people who read EEGs to get them educated in how to do that.
Alex Tsakiris: Well, we’ll definitely point people to that if they are interested. Thanks so much for joining us.
Dr. John Greenfield: Absolutely. Thanks very much.
Alex Tsakiris: Okay, that should really put this issue to rest. You know, he’s a little bit circumspect in the first answer that he gives, but really as he gets into it more and more you can tell he’s trying to couch it in careful medical, scientific terms and not being completely certain, but in the dialogue that I had with him and in the e-mail exchange with him, he made it quite clear that it just makes no sense to suggest that someone is having a near-death experience as we generally understand it and they’re having a flat EEG. That’s a dead issue. If you’re pushing that, you’d better bring some new fantastic data because it contradicts everything we know about how the brain works.
Okay, so on to issue two, and that is could the near-death experiencer be remembering things after their brain is back online? That is, not during the time while they’re having a flat EEG? Now some very good research that directly addresses this issue has been done by Dr. Penny Sartori, who was working under Dr. Peter Fenwick, who you’ve heard on this show before.
Now Dr. Sartori was nice enough to join me for an interview today, and the interview starts with me kind of jumping right in and you’ll hear her response to the e-mail question that I sent her regarding whether Michael Persinger’s claim of the flat EEG could possibly be true. You’ll hear her say you know, very proper and qualifying and say, “We really don’t know, and maybe not and who knows,” but as you just heard, if you really talk to a neurologist, if you really look at any of the evidence, that really doesn’t make any sense. But listen to that and then listen to the other parts of what she has to say about her research. Fascinating stuff. Here goes.
Dr. Penny Sartori: And yeah, it’s quite interesting really, what he said and you know, at the moment he’s quite right. We don’t know with EEGs, it does only measure the surface of the brain function and so yeah, sure, there could very well be deeper processes going on that we’re unaware of at this present time. That’s why it’s so important to continue with this sort of research, really, to find out more and answer these questions.
Alex Tsakiris: To me that’s inadequate and it feels like sometimes we spend time on the other guy’s playing field, if you will. I mean, Dr. Persinger, I had a delightful conversation with him and he’s very knowledgeable in his view of things, working with the God Helmet and all that. But to me he’s suggesting a whole different interpretation of the way the brain works, particularly with such lucid, coherent experiences as are reported in the near-death experience.
And then to suggest that that wouldn’t show up in an EEG, in my understanding, my limited kind of hobbyist understanding of it, goes against all the human research on EEGs, plus some really more tightly controlled animal research on EEGs and how the brain works. I don’t know how you can just proclaim that if you’re him and suggest well, there’s some big mystery out there that we haven’t solved in terms of how the brain works.
Dr. Penny Sartori: Yeah, at the moment we really don’t have such a great understanding of how the brain works, especially in relation to consciousness. I think you know, the current newer scientists are looking at the brain from our current viewpoint that consciousness is a by-product of the brain. And I think the more we research that we’re doing into near-death experience and is showing that perhaps this view of consciousness is perhaps not correct. It could be that rather than consciousness being a by-product of the brain, maybe the consciousness is just mediated through the brain.
Alex Tsakiris: To me, that seems obvious, an obvious interpretation of the results. Even Dr. Persinger – and I don’t want to focus our entire interview on the follow-up with what he had, but he suggested that some of his other work has been highly suggestive that telepathic communication happens. He connects two people up to the God Helmet in different rooms and flashes light on one and it shows up on the EEG of the other, kind of replicating the Ganzfeld work that’s been done by Dean Radin and a number of other people. So I guess the question would be aren’t we ready to kind of overturn that mind equals brain model, or do we have to still kind of carry it around and defer to these existing belief that so many neuroscientists have that to me just seems completely overrun by the data that is mounting daily, that comes in.
Dr. Penny Sartori: Yeah, I think you’re quite right there. You know, the more research that is being done is showing that our view is really perhaps inadequate and I think it’s really exciting that all this research is being done, because it’s given us new answers as well, and it’s given us new avenues to pursue. So I think it’s really important to continue with this research. And as you quite rightly said, it is an overwhelming database there now showing us that these things perhaps we need to take forward and perhaps we need to review our current views of science.
Alex Tsakiris: You know, Dr. Sartori, one of the most fascinating pieces of research in this whole area is some work that you did with patients who had been recently resuscitated from a cardiac arrest and then you asked them to recount the resuscitation process. For those folks who maybe aren’t familiar with that research, can you tell us a little bit about why you embarked on that research and what you discovered when you did that survey?
Dr. Penny Sartori: Actually, yeah, I worked as a nurse in the intensive care unit and because of the nature of my job, of course, I’d come across a lot of death. And of course, you see so much death, it just makes you wonder what happens when we die. It was a patient in particular who I was looking after and it really upset me a lot and it made me ask these philosophical questions about life and about death. Then I started reading about death and then I came across near-death experiences and I thought, ‘Wow, these people are telling us that death is nothing to be frightened of.’
And I thought to myself, ‘Well, with regards to my scientific training as a nurse I just thought that these experiences were just some sort of hallucination or some kind of wishful thinking as you come close to death.’ Indeed, I remember as a student nurse a patient confiding in me about her near-death experience, and at the time I listened to her but I didn’t think that there was anything in it. I just thought it was some sort of hallucination on her behalf. And although I listened I didn’t actually ask any further questions because I didn’t think there could be anything true about this experience. It was only later when I actually started reading about near-death experiences that I realized what this lady had told me.
I just thought, ‘Well, I’m working in the perfect environment to research these experiences.’ So I decided to undertake my own research project. For five years I gathered data, where I spoke to people who had been patients in the intensive care unit and particularly focused on patients who’d had a cardiac arrest. So these patients had been clinically dead for some period of time and that their heart had stopped beating and blood wasn’t circulating around their bodies. When these patients revived, as soon as they were medically fit, I approached them and I introduced myself and I asked them the simple question, “Did you have any memory of the time that you were unconscious?”
Now a lot of these patients didn’t remember anything at all, but there were a few patients who did report some very interesting experiences. This is something that really does fascinate me. In total, out of the five years, I interviewed over 300 patients. Not all of these patients had had a cardiac arrest because during the first year I interviewed everyone who had been a patient and survived in the intensive care unit regardless of how close to death they came. I wanted to see if maybe just the thought that they could be close to death could in itself precipitate an experience. This didn’t seem to be the case.
Then for the next four years I concentrated solely on the patients who had had a cardiac arrest and so had survived clinical death. What I found is that although the sample is a lot smaller than the first year’s data I found that quite a large group of these people did report experiences consistent with a near-death experience.
Alex Tsakiris: And what about the work that you did in comparing their recollections of the resuscitation process versus the control group being people who hadn’t recalled any near-death experience?
Dr. Penny Sartori: Yeah, that’s right. Well, what I did is the people who had a near-death experience and the out of body experience, that what they recorded was really quite accurate and I decided then to ask the control group, the people who’d actually had a cardiac arrest but had no recollection of anything at all. I asked them if they would reenact their resuscitation scenario and tell me what they thought that we had done to resuscitate them.
And what I found is that many of the patients couldn’t even guess as to what we’d done. They had no idea at all. And then some of them did make guesses, but these were based on TV hospital dramas that they’d seen. I found that what they reported was widely inaccurate. Some people just made educated guesses. What I found was that some people are sort of under the misconception that they had had a dc shock when in fact they had only had chest compressions and drugs administered. Then the ones who did have a dc shock I found that the patients guessed the wrong position of where these shock paddles would be placed on the body. So there was a stark contrast really in the very accurate out of body experiences reported and then the guesses that the control group had made.
Alex Tsakiris: You know, Dr. Sartori, in the past I’ve spoken with a couple of guests who’ve worked in hospice, either as a nurse or physicians who’ve worked with people who are close to death. What they reported is that the culture and the common understanding among people who work with folks who die, they just have a different sensitivity and a different openness to this kind of information. I’m wondering if you’ve found that in intensive care? Are doctors and nurses who work with a lot of patients who’ve passed or pass and come back, are they more accepting of this kind of strange survival of consciousness phenomena?
Dr. Penny Sartori: Yes, certainly. When I was my first day on the ward as a student nurse I can remember we were having handover in the office from the shift before us and the nurses handed over, she said, “The man in bed 2, he’ll die shortly because he’s already started communicating with his dead mother.” Now I thought this was something to scare me because it was my first day on the ward. But I looked around and the other nurses just carried on as if this was something normal. Then lo and behold, within two or three hours of the shift beginning, this man actually did die. That is something that’s always stuck with me.
Certainly throughout my training and my career as a nurse, when I worked on the wards, when patients were expected to die it was common to see them communicating with people that we couldn’t see. For example, very often they’d have big smiles on their faces or they’d be gesturing to someone that we can’t see. It’s not quite so common in intensive care because a lot of the patients towards the end of their life are sedated, but certainly for patients who are not sedated and are coming to the end of their life, that is something that has been witnessed by many nurses and many doctors. It is very much accepted.
Alex Tsakiris: You know, I find that kind of disparity between medical knowledge and folks who are working with folks who are close to dying and those who are not as being just another interesting aspect of this whole puzzle.
I mean, one of the things in this whole field that just intrigues me is how there can be this willful ignorance on the part of so many folks who really should know better about this phenomena. I wonder if you have any thoughts or explanation for why there is this seemingly unexplainable lack of acceptance and knowledge about this? Obviously, it’s a controversial area. It’s a scary area. Why can’t we get closer to it from a scientific medical standpoint? And I know we are inching closer to it but it just seems like it’s such slow, slogging through the mud kind of progress.
Dr. Penny Sartori: Yeah, well, I think a lot of people are just sort of very much set in their ways, perhaps, and they don’t think about things like this, you know? It’s only when I actually started thinking deeply about death that I got a real interest in these sort of experiences. Prior to that I just thought, ‘Oh, no,’ I just dismissed them and just thought, ‘No, these are just hallucinations. There can’t be any truth in them.’ But I think you know, it’s only when you start looking at them very deeply and you start thinking a lot about them and then you relate what you read and what you see and what you actually encounter in the work area of the hospital.
So I think a lot of people certainly don’t think very deeply about it. They’re not exposed to it, either, you know? Not many people work as – well, people do, obviously, there are doctors and nurses who don’t believe in these sort of things and just continue to dismiss them. But I think a lot of people are still sort of entrenched in that belief system that these things can’t possibly be true. You know, it’s only recently really that this sort of research has become quite formal and been quite – how can I say it? It’s sort of like taking off, this kind of research really compared to what it’s been in the past.
Alex Tsakiris: Right. And we can only hope that it’ll continue in that direction and really catch up with the public because I think the public has been much more accepting of this phenomena as a whole than has the medical community and the scientific community. Which also leads into maybe you want to comment on what I perceive as a certain disenchantment that the public has with science in general. You don’t see it in all areas.
Certainly I think people are very accepting of the wonderful technological toys that we have, but I think this especially maybe more in the States than in Europe and the UK, but there’s this sense that gee, science, if you haven’t solved this thing that I know is real because someone in my family had it or someone very close to me experienced this, then how can I be so sure that you’re right about some of your other conclusions? I wonder if you have any comments on this disenchantment that many experience with the scientific explanation when they encounter directly experiences like this that science up until very recently has been very closed to explaining.
Dr. Penny Sartori: Yeah, I think a lot of people do become disenchanted really with science’s perceptions and current stance on these things, but I think a lot of people now are looking for alternative explanations, if you like. I think that perhaps this is why this sort of research is so popular with people out there, the general public. They want answers. They’re not satisfied with the current scientific explanations because of experiences that they’ve had or encountered with members of their own family. So I think a lot of people are looking for other answers as well.
Alex Tsakiris: Yeah. So thanks so much for joining us. Tell us what’s coming up for you in terms of future research or maybe writing projects?
Dr. Penny Sartori: Well, I’m currently sort of working on more writing and working on a mainstream book to do with my research. I’m currently involved with the Global Aware Project which is headed by Dr. Sam Parnia. You’ve probably heard of this project. It’s basically a global scale project on the work that I did.
Alex Tsakiris: Yes, we had Dr. Fenwick on the show several months ago and he talked about it. Maybe you want to tell us a little bit about your involvement in that and what you see coming up with that and when we might expect to see some early results from that.
Dr. Penny Sartori: Well, the hospital research is underway at the moment. It’s been up and running for approximately two years and it’s gathering data from different hospitals throughout the UK. I think there’s about 15 hospitals from the UK involved. There are hospitals in America. There’s hospitals in Vienna. And there’s a part of Europe taking part in this research. We hope to get a large database of people who’ve had cardiac arrest and examine the sort of experiences that they have had and the impact that these experiences have on their life as well. We’re hoping to publish something on this project sometime in the next few months, hopefully.
Alex Tsakiris: Wow, that’s great. I didn’t realize some early findings were going to be out that soon. That’s certainly exciting to look for that.
Dr. Penny Sartori: Yes, yeah. But you’ll have to speak to Dr. Sam Parnia about that. He’s heading that aspect of it.
Alex Tsakiris: Well, thanks again so much for joining us. Very interesting work and we certainly wish you well with it.
Dr. Penny Sartori: Oh, thank you. Thank you very much.
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