Latest / Art of the Question / The Science Behind Near-Death Experiences - Dr. Charlotte Martial - #35

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The Science Behind Near-Death Experiences - Dr. Charlotte Martial - #35 · Art of the Question

• Julius Moorman: But yeah, Charlotte, like I said, thank you so much for meeting with me today. I think you have a very, very interesting field of work. And first of all, I was kind of curious to understand how you first got into studying near-death experiences and ⁓ what interested you about this field of science. Actually, I job in the field. kind of by chance. It was the other. I wanted to work on neuroscience and so I had this topic that was suggested by my previous thesis promoter. But as soon as I started to work on the topic, I was fascinated by the phenomenon and also seeing that while in research ⁓ there was They were very limited, empirical, rigorous research. So I really wanted to focus on the topic and help the field to understand the phenomenon. Yeah, I can imagine. And I can also imagine that it must be a pretty difficult field to study because I recently did an episode about the feeling of awe. So the feeling of being awe-inspired or feeling awe. And one of the topics there was that it was kind of difficult because awe is something you experience randomly. You can't really plan for it. And it's also highly personal, right? And I can imagine with a field like near-death experiences, It must also be quite challenging at times because obviously the subjects, you can really almost ⁓ kill a subject. that's why it must be very interesting. Is it indeed a very challenging field to study? Yes, I would say that it's very challenging. Because yes, first we depend on the first... a first-hand account of the person. So we depend on the memory of the phenomenon. So of course we have to set up our research based on that. And so we necessarily ⁓ depend on the memory, on the subjective experience of the person. Plus another difficulty is that ⁓ we can never plan ⁓ its occurrence. So it's a spontaneous naturally occurring phenomenon that ⁓ arise in extreme physiological stress. So as a researcher, it can be complex to set up some specific empirical research, but I guess we can also talk about that later. How to design, how to set up, how to approach the phenomenon. ⁓ Yeah, of course. Now I'm very, very happy to get into that. So I'm very curious about that. Before we get into the specifics of the field and what it entails and how we study it, ⁓ when did this field arise? Like when did scientists first start to seriously study near-death experiences? Like how long have we been doing this? Sorry. No worries. Actually, since the dawn of time, we can see representation of near-death experience. we think that for decades at least, humans have experienced such a phenomenon. But the particularity of the field is that it's only for the last 15 years that researchers and clinicians have been interested by the topic. So I think that all start with the publication of the bestseller ⁓ book of Professor Raymond Moody, ⁓ Life After Life, that was published in 1975. started from there, we can see the first researcher, clinician that start to ⁓ collect testimony that start to ⁓ analyze, characterize the phenomenon using the tool of psychology, but also more recently, neuroscience. And so we can clearly see, I would say, an increase of interest for the last 15 years, where I can see that researcher and clinician from different kind of field are now more and more interested by the topic. But for those who are familiar with the scientific literature, if today you go to the PubMed research website which gathers all the psychology and biomedical research, we can find only like 460 publications on the thematic, which is still very limited. ⁓ Okay. Okay. So it's, yeah, it is still a niche field of science. Yeah. Now I can imagine. if we're talking about ⁓ the scientific definition of a near-death experience, ⁓ what do we count as a near-death experience? When are we talking about ⁓ a near-death experience? So a near-death experience or NDE. is an episode of disconnected consciousness, meaning that it's a mental experience that ⁓ is distinct from the physical environment and that occur in a severe physiological crisis such as cardiac arrest, trauma, etc. And the particularity of the phenomenon is that they contain recurring prototypical features such as out-of-body experience. seeing entity, seeing a bright light, et cetera. However, this is, would say that it is my definition. But so far the scientific community has not, I would say, decided one single unique, one single definition for the phenomenon. Right. So it's an umbrella term that encapsulates a range of experiences. And what I was curious about, does someone actually have to be close to death to experience one? Or if someone believes they are about to die, can that also be enough to trigger it? Yes, good question. Because indeed we observe that people who just believe that they were close to death, report the same kind of phenomenology, so the same kind of subjective experience. And interestingly, ⁓ after a few years I ⁓ in the field, ⁓ I received actually, ⁓ I started to receive several emails by people who were, who don't even believe that they were in a life-threatening situation. And actually some people seem to report similar phenomenology in, I would say, random conditions where their lives were not threatening, such as ⁓ after ⁓ fainting or after just a high ⁓ anxiety, etc. So the idea is that we should see near-death experience and near-the-like experience phenomenology as a continuum of subjective experience where actually It seems that human can experience this subjective experience in any kind of particular condition or situation. Right. That's super interesting that it is when the body believes it is going there that these effects occur. And if we talk specifically about what happens and what people report to experience because obviously we've heard about a bright light and perhaps looking ⁓ on themselves from above. what is the experience that people usually report? Because I believe a lot of people, and that's part of what makes it so interesting. is that ⁓ many people across different cultures roughly report the same phenomenon, correct? ⁓ Yes. basically you have a series of, I would say about 20 features that seem to be recurring in the testimony. However, we don't observe one single feature that is there in every testimony. Yes, we have those kinds of, I would say, mystical features where the person is, for example, ⁓ meeting an entity, be it a presence of or a person that they know and that may be ⁓ diseased. ⁓ It can be also ⁓ sensory perception, as out of body experience, where the person has the impression to be out of their body, etc. ⁓ And it seems that the interpretation of the experience ⁓ is also influenced by the cultural background of ⁓ the person. the empirical literature in this field is very ⁓ limited, but we observe that for European and North American ⁓ person, we observe, for example, that the frontiers of ⁓ the impression to get at the frontiers or the impression to be close to death or in a getaway is ⁓ interpreted as, I would say, at least reported as a tunnel. While we can observe that in Asian testimony, it seems to be more like a river where we see that and we know that the river has a particular religious importance in those areas of the world. So ⁓ just to say that I think that there are some specific neurophysiological and cognitive mechanisms that lead to some specific feature. But then, of course, the interpretation of the person is ⁓ very important as any kind of subjective experience that we live in everyday life. Right. Now that makes sense. of course, and the river, for example, that sounds really peaceful. I believe the entire experience is described as quite calming and quite ⁓ peaceful, which for some people might sound strange because when we think about death, it seems like a horrible experience and seems like something out of a nightmare. But that's not really what people report, is it? People report, I believe, very intense, but also calm, like it was almost a serene moment. What do you make of that and is that a correct understanding of what's happening? Exactly. The idea is that most of the people indeed report this intense feeling of peacefulness and a calmness experience and something very serene, which is ⁓ which may seem actually paradoxical, right? However, now we can start to explain this impression, this sensation of peacefulness, notably by the massive release of some specific neurotransmitter, ⁓ such as endorphin and noradrenaline, that is actually there to help the person to face this. life-threatening or painful or stressful situation. ⁓ So I would say that at first glance, it seems paradoxical. However, we can now explain it, ⁓ I would say, ⁓ in a perspective that the phenomenon, the feeling is part of a more general, a more broad defense mechanism to face the life-threatening situation. Right. Because is that ⁓ Also the working theory or is that our current understanding of why we experience near-death experiences is that our body prepares itself for this moment and therefore it produces chemicals inside the body to make this experience less painful? Yes, that's exactly that. And we have notably some animal studies ⁓ in notably ⁓ asphyxiated rats. that show this massive release of ⁓ neurochemical that may permit in humans, at least this sensation of peacefulness. Super interesting. what kind of, you briefly mentioned them there, but ⁓ what exactly is being produced on a chemical level inside the body and how, what are the effects of that? ⁓ Yeah, mostly calming, but ⁓ maybe we can dig a little deeper into dose. Yeah. So the idea is that ⁓ we recently published a comprehensive model where we try to gather all the psychological, neurophysiological, but also evolutionary framework to explain the phenomenon. And so ⁓ the central idea of the the model is that near-death experience may emerge from a complex interaction between brain, body and mind process. ⁓ And so in short, when the brain is deprived of oxygen level rise, it creates a notably a lack of energy in brain cells. And so this may trigger a chain reaction of specific ⁓ neurochemical ⁓ a mechanism that will actually make certain brain areas, like those involving perception, consciousness and memory, ⁓ much more active. we can see, well, we hypothesize here that the brain will release this large amount of natural chemical that will ⁓ permit to ⁓ generate some specific feature. And in this model, what we propose as new was that we started ⁓ to link some specific neurotransmitter system to some specific features. And this is based on empirical literature in humans, but also animals and also what we know. about the neurophysiology. so basically, to give you some examples, we just talk about the impression, the sensation of peacefulness. But for example, we also suggest that ⁓ the glutamatergic neurochemical system may permit the dissociation, the mental dissociation from the physical environment to permit the mental experience to arise. We also suggest that, for example, the serotonin-ergic ⁓ system may permit all the vivid image. ⁓ Also, in terms of memory encoding, we suggest that the neuroadrenaline, but also endorphin may permit the memory to be ⁓ encoded in this severe physiological stress. Yeah, no, and that's interesting because so it is both obviously a lot of studies and a lot of science is done both on humans, also on animals, of course. we've seen animals do also experience a form of NDEs. Well, not really, because of course we cannot ask them properly in the deep experience. ⁓ a subjective experience like Andy ⁓ However, and this is part of our theory, ⁓ we actually suggest that Andy may be ⁓ actually the evolution of ⁓ what we have, what we can observe in animals, the behavior of Thanatosis, which is fainting death. So ⁓ you may know that in plenty of species, animal species, we can observe this tannotosis behavior, which is basically fainting death when a predator arrives ⁓ and ⁓ when the flight or fight response is not possible, the animal may faint to death. ⁓ in order to have the predator to live and let him alive. And so we suggest that ⁓ with the evolution of our brain that is, I would say, way more complex in humans, right? And the acquisition of language, etc. We can see that ⁓ this Thanatosis behavior may have evolved into a very complex subjective experience than maybe near-death experience. So basically what we suggest, even if I'm not sure we can like properly empirically prove it one day, but we suggest that tinnitus in animals versus, no sorry, tinnitus ⁓ in animals and near-death experience in humans have actually in common this biological, I would say biological purpose that permits the person to survive the light returning situation. That's cool. That's an interesting parallel. I can understand that. Yeah, that makes a lot of sense. And what I was curious about, because we're talking about science, of course, and what happens on a chemical level within the body. I believe at least from some people, from some remarks that it is also in different cultures associated and near-death experience with a religious one that the bright light that you see would be entering into heaven and depending on which religion you have it can have different meanings but I believe it is reported that ⁓ some religions interpret this as entering into the afterlife and that you're still conscious and that your soul kind of leaves your body and enters into this new world. Do you think that this can go hand in hand or have you met any resistance into studying this and like getting into the ⁓ sciency part of it or do you think like these interpretations can coexist? Well, I would say that it's difficult to say so far because, ⁓ well, ⁓ so far we don't have any empirical proof that it exists in life after life. So I think that here it's very important to dissociate science from ⁓ beliefs, right? Exactly. And so I would say that whatever the beliefs of the person, ⁓ science is trying to explain the phenomenon and of course the interpretation of the experience may depend on the spiritual ⁓ and religious beliefs of the person. But I think here it's very important to distinguish ⁓ both, right? We don't talk about the same thing. With science we are trying to approach the world to understand the phenomenon ⁓ using ⁓ some specific methodology. While ⁓ when we talk about beliefs, it's not the same perspective, right? No, I agree. I agree. understand. Yeah. And ⁓ I think one of the most famous examples of a near-death experience, I think the most classical one is I saw my life flash before my eyes. that's ⁓ one. that you read in books, you've seen in movies, like right before you die, you see a replay of your entire life. Is that more like an urban myth or is that actually what some people report? What's the data? What does the data say on? Well, indeed, we have some people that report this life review at some point. ⁓ during the near-death experience or just when they are close to death. But so far, from what we know ⁓ about neurophysiology and consciousness, ⁓ this is actually, I would say, a vivid imagery that ⁓ the brain created at that time. Yeah, no, I'm just curious too. Like it's to me, it's one of the most classical examples of what people describe as an NDE. And they said that right before it's over, you see your life flash before your eyes. And it would be some, think the most classical explanation or phenomenon is that ⁓ people see their life from, from birth. and then go all the way up to that moment or it is a replay just all the way from that moment. ⁓ It's like a fast forward imagery of their entire lives all the way to their time as a child again. So I was just curious to hear if that's something that we just hear about in movies and it's just basically a saying, I saw my life flash before my eyes. or if that's actually being reported and reflected in the data. So yeah, indeed this feature is sometimes reported by people who have been close to that. I would say that as compared to other features such as other body experience, it seems to be less common, less frequent, at least in the empirical study that we have so far. And from what I saw it seems that it may depend. ⁓ So sometimes it seems to be a very ⁓ short and rapid ⁓ succession of image and scenes of ⁓ the person's life. And sometimes I would say it's a more complex ⁓ scenes. So I would say that it really depends on the testimony on the person. Right. Now that makes sense. And you mentioned the outer body experience there. That's a very interesting one to me because I can understand why certain chemicals would produce ⁓ bright flashes or a very strong, like a serene feeling having a peaceful, but having an outer body experience where you can actually see yourself sitting and where people report their souls actually leaving their body and being able to look down on themselves in the very room that they're lying in that seems a more yeah that means whether that is like actually happening or whether it is some a form of hallucination but it seems harder to to explain to me i think that's that's a very interesting one within the things that people report ⁓ Can we maybe dive into those? What do people usually report when they have an outer body experience and ⁓ can it be explained in some way? Yes. Well, I would say that here again, it's very diverse what we can see as testimony. have those ⁓ simple self-perception, distorption ⁓ where the person not necessarily see properly imps his body as a third person. And we can have also like very complex, complete ⁓ dissociative experience where the person is, for example, clearly ⁓ out of his body, seeing imps his body from a ceiling perspective, right? And sometimes kind of observing what is going on around the body. ⁓ And so it's all about whatever the complexity of the subjective experience, it's all about dissociation ⁓ process. whatever the complexity and the vividness of the experience, ⁓ think this is, I would say, based on the self-perception, distortion. And so ⁓ it's a kind of what we say, connected consciousness, meaning that the person is sometimes aware of what is going on in the physical environment and later on will include some visual perspective that is sometimes like from a ceiling. so ⁓ here there is all this process that we call memory reconstruction that is happening to help the brain to ⁓ make sense of what is going on. ⁓ Yeah, super interesting. And ⁓ maybe if we talk about the specifics of studying it, we briefly touched on it in the beginning, but I'm curious to understand the process ⁓ of how the science is being done on ⁓ NDEs because it seems so challenging to me and therefore, yeah, extremely cool as well. ⁓ I would say that there are two kinds of empirical research we can do. ⁓ The first one is ⁓ laboratory experimental, sorry, the first one is lab control laboratory ⁓ experiments where we can induce phenomenology that resembles near-death experience. So for example, we can use ⁓ psychedelic substance, we can also use fainting, as I said at beginning, there is this phenomenon, this similar phenomenology that arises when people faint. So it's all a kind of method that permits to induce phenomenology that resembles ⁓ involunteers that we invite in laboratory settings. And since we are there, we can study the phenomenon prospectively, for example, using EEG so that we can see what is happening in the brain while experiencing this those near-death-like experience features. Next to that, we have the clinical research, of course, where we follow patients that are close to death. With my team, we have conducted several studies where we follow patients who were managed in emergency conditions and also in intensive care conditions. Basically, the idea is that we follow them as soon as they arrive at the hospital. We interview them ⁓ as soon as they are awake, conscious, and that they can reply to our question. And we can also, of course, ⁓ follow them for months or even years to study the impact of the experience. I would say that this is those two kinds of apical research. And ⁓ maybe a third kind is also simply using questionnaire that we can easily send to a large... a sample of patients who have experienced, near-death experience years or even decades ago that permit to characterize the phenomenon, but also the memory ⁓ and the consequence, etc. Yeah. And memory, because it is such a... Well, it is a profound experience, if anything, at least people report it to be. ⁓ Do people usually have very vivid memories of their NDE? Yes, it seems that they have very vivid memories of what is happening, at least in the retrospective study that we have so far. However, ⁓ would say that it's kind of limited. We have only like, I would say, three papers, empirical papers that focus on that question. So ⁓ we are actually conducting a prospective studies at the hospital to also better characterize this memory characteristics. So we are waiting the result to see if we confirm this vividness or not, to see if it's happened from the acute, so from the first hours just after the event. Right. And it also makes sense, right? From an evolutionary perspective is that usually when something requires our absolute attention or when we absolutely need to remind something, that's usually why it feels like if you have the adrenaline going, why time appears to slow down because we're in this hyper vigilant ⁓ status and our body is being told like you should pay attention now. And that's usually when I think back of maybe traumatic experiences or some things that made a huge impact on me. can usually replay those incidents in my head very accurately, which makes sense because it's our bodies are being told, hey, something important is happening. You better pay attention and don't forget that this has happened. Is that also why people think like we remember these NDEs so vividly? Indeed, that's clearly a possibility. Yes. Yeah. Makes sense. And of course we've been talking about what immediately happened during a near-death experience or shortly after, but it can often be a life-changing event, I assume. ⁓ What do people report after? Like how does it change their lives in any way? And is that sometimes positive or over negative or sometimes also positive? Yes. So indeed it seems that there are like acute, but also lasting ⁓ after effects of the experience. So if I have to sum up the main ⁓ consequence, I would say that the most frequently reported consequence is the fact that usually they are not afraid to die anymore. So it's really a decrease of fear of death. Also, other consequences are the fact that after the near-death experience, they may feel more connected with others, more connected to nature, but more so ⁓ connected to any kind of spiritual element. ⁓ So I would say that they consider themselves as less materialist after the experience. And from the negative consequences, I would say that the most frequently reported one is the fact that they have difficulties. The negative consequences, I would say that maybe the most reported ⁓ after effect is the fact that they have these difficulties to integrate this ⁓ experience that has, I would say, mystical and extraordinary aspect with them being out of their body, etc., into their daily life. So it's sometimes hard for them to integrate, to understand the phenomenon and ⁓ integrate it into their ⁓ daily life. ⁓ So I would say that the after effects report it really depends on the person, but those are the main one, I would say. Yeah, and I can imagine, right? Because also you sometimes hear people report having a life changing experience after a strong psychedelic experience, for example, when people just have a new perspective on life and see things in a different way. And I imagine that this can be pretty similar. Is there a relationship between psychedelics, for example, DMT, I see mentioned in this ⁓ regard as well. And if so, what is the relationship between ⁓ DMT and NDEs? Yes, so we have with my colleagues from the Paralympic College London and UCL, and notably Christopher Timmerman, we observed several years ago that it seemed that the phenomenology induced by specific ⁓ psychedelic substance may really result in near-death experience. So we compare it with a laboratory control experiment where volunteers were induced DMT experience with, I would say, typical ND report. And we observe that there is ⁓ a large overlap in terms of phenomenology, except that, for example, in this publication, we observed that there was only one single feature that seems to be more often reported in ND as compared to DMT, which is the impression to arrive at the frontiers, ⁓ so representing, I think, the dying process. ⁓ And so in general, more broadly, I would say that there are some specific psychedelic experiences that seem to really resound. NDE such as DMT, but also 5-MAO-DMT ⁓ or also ketamine or the salvia divinarium substance. ⁓ interesting. ⁓ ketamine has some similar effects as well? Indeed. Ketamine seems to ⁓ induce near death like experience feature. Well, it's mostly about the dissociation. the impression of being out of your body, but also some, ⁓ depending on the doses, we can see some specific feature, ⁓ typically reported in ND, reported in ketamine induced ⁓ experience. Interesting. And how does that help the science? So we understand like, some of the DMT experience is similar to an NDE. some of the ketamine experience can also be similar to experience an NDE. Does that help the science, for example, to maybe be able to better reproduce certain scenarios? Or what else is the benefit of finding those similarities in these substances? Yes, exactly. So I would say that it's helping two things. The first one is that it helps in developing the neurophysiological hypothesis that we have because ⁓ as you may know, the psychedelic literature is really emerging and we see more and more abirigal research that permits now to characterize what is going on in the brain for some specific ⁓ psychedelic substance. so knowing that, we can develop specific hypotheses for near-death experience. And then, as you said, ⁓ This can be used as a safe and reversible model in laboratory settings to induce similar phenomenology. And so that we have ⁓ a secure model in laboratory settings to ⁓ study the phenomenon. That's very, very interesting. And are there besides DMT and Academy and any other substances that are currently being looked into? I would say that that's the main one. ⁓ But actually we are trying to find funding to develop other psychedelic experience. But so far that's the main one. Okay. Yeah. Makes sense too. And when we talk about what we've talked about, obviously the chemicals that are being released inside of our bodies. But if we talk about the brain specifically, because it would make sense that if someone is almost going to die, that our brain shuts down basically. That's what you would expect. But is that also what is happening or what is actually happening inside the brain during these experiences? Yeah, that's a good question. Indeed, ⁓ we can think that it's the case. However, What we actually have learned ⁓ over the past decade from both humans and animal studies is that the brain is actually not immediately silent when the herd stops. So we observe ⁓ that cardiac arrest actually initiates a dynamic process ⁓ in the brain that permits some specific region of the brain to be ⁓ to be ⁓ active. And so it's not because you have your heart that stops that your brain ⁓ necessarily immediately stops. And so this is where I think we need more empirical research to really understand ⁓ this phenomenon. ⁓ Plus, we also know for now two decades, I think, or even more, ⁓ that with plenty of kind of empirical research that ⁓ Consciousness does not necessarily require the entire brain to be ⁓ functioning and experience subjective experience. So we have now evidence from neuroscience literature that suggests that some specific part of the brain, some specific network, and notably the temporal parietal network, that may be sufficient to generate complex conscious experience. And so even in a condition where a global brain function is severely compromised, ⁓ actually we would only need, I would say like pockets of activity within some specific network involving perception, self-awareness, consciousness, emotion to remain active and then permitting to ⁓ experience the phenomenon. Yeah. Wow. Okay. So, ⁓ There is evidence to suggest that we only need a very small portion of our brains, a small pocket of our brains to experience ⁓ consciousness. How did we figure this out? Because consciousness to me is one of the most interesting topics within science, within philosophy, within psychology, because it is first of all super hard to define and We kind of know what consciousness is, right? If I ask you or you ask me, are you conscious right now? The answer is probably a very easy yes. Yes, we are both conscious. We are having this conversation right now. But sometimes, and this is something I talked about with philosopher Henry Schevlin a couple episodes back, is you know that feeling when you're driving in your car on the highway. And then after maybe 20 minutes of driving or an hour, you kind of snap back into reality. You were driving, but you were on autopilot and you didn't crash into any cars. You were completely fine, but you weren't aware of the fact that you were driving. And another interesting one is, is sleeping, right? So if I'm sleeping, sometimes I'm Kind of conscious when I'm dreaming, when I'm having a very vivid dream, I would say that's some sort of a conscious experience because it feels like you're alive and you're doing stuff. But for the parts that you aren't dreaming. Yeah. Are you still conscious? it ⁓ like a light switch? Like, are you either conscious or you aren't conscious? Or is consciousness a skill? Can you be? somewhat conscious. to me, consciousness is like endlessly interesting. So I'm definitely very eager to hear more about this study that you just referred to and how they determine that only like small pockets of brain activity can produce consciousness. Yeah, well, I think here it's like the main question of this neuroscience decade where the conscious and the current ⁓ consciousness researcher and philosopher are really trying to understand that problem that we call the art problem of consciousness. this difficulty to explain. today, all the subjective experience may arise from the neurophysiological ⁓ mechanism, right? And so we have, for example, fields such as disorder of consciousness patients who show some patients who have severe ⁓ brain lesions but can show some specific ⁓ conscious experience. And so, ⁓ just to say that indeed, consciousness is a very complex phenomenon. this is actually why we have also those ⁓ famous consciousness theories. So, ⁓ I don't know to what extent you are aware, but there is, I would say, like ⁓ five or six main consciousness theories that try to explain how consciousness arise. And they are currently ⁓ fighting, I would say. ⁓ between them by comparing how they explain, how consciousness mirrorizes. So for sure we are at the beginning of this ⁓ understanding and of course ⁓ one of the limitations is that we depend on the tools that we have today to understand the phenomenon. So we have, for example, EEG, FMI, etc. And so we depend on those tools that can assess what they are designed to assess, what they aim to assess. so maybe we would also need more, ⁓ well, we would need different tools to better understand consciousness. And so ⁓ here I don't say that we have understood consciousness and which part of the brain are important, but at least ⁓ We know that we don't need our full brain to be conscious and we know that ⁓ some specific part of the brain seems to be more important ⁓ in some specific condition to ⁓ generate consciousness. We also know that some other parts are more associated with the sensory perception of our body, for example. I think that Andy here, here, sorry. I think that NDE is very important because if we want to understand consciousness, human consciousness, we also have to understand it ⁓ in conditions where we don't expect it to arise. As you said, we won't expect during a cardiac arrest to have this subjective experience, while actually it is the case. So I think ⁓ it's a unique opportunity to explore the minimal condition necessary. for ⁓ consciousness to occur. I agree. And I think that's part of the reason why it's such an important field, right? Because it also borders on ⁓ being in a coma, for example. So if we understand what's the bare minimum necessary to ⁓ within the brain on a physiological level to produce consciousness within humans, that might also be very interesting knowledge to have. ⁓ to know how we should treat certain patients who we deem to be brain dead and only physically alive, but they may very well be having ⁓ very conscious experiences. We are not brain dead, right? No, it's a good correction. ⁓ how do I know? No, no, no. What's the correct term of? when we obviously not when we're having a near-death experience, I should have worded it better, but I can imagine that there are certain scenarios where we assume that someone is so far gone that it would be unlikely that he or she would be able to produce a conscious experience, whereas This seems to imply that even if we only use small parts of our brain, that it can still produce such, which may be very important to help treat certain patients. Yeah, exactly. And I think that's why consciousness literature is so important, is not only to help those patients with disorder of consciousness. ⁓ And yeah, I think that Actually, we can cite ⁓ several conditions where we won't expect humans to have consciousness. While we now know that with their report upon awakening, did experience a ⁓ complex or subjective experience, conscious subjective experience. Yeah. Yeah. And I think it's also interesting. to know what happens during the near-death experience because it kind of seems like a ⁓ gateway moment in the sense that before you die you are presumably awake and therefore you are also likely to be conscious. ⁓ At least right now from a scientific point of view when we die we are not conscious anymore. After we die similar to the that we aren't conscious before we are born. Like I can't remember anything from before I was born. So therefore I probably wasn't conscious. At least I can't really remember anything from before I was born. And presumably I won't remember anything or won't be conscious after I die. So I think that's also an interesting moment because it seems to be a border, a passing, a gate. way between the two. And ⁓ I'm curious because ⁓ the consciousness problem is not only difficult because it is, yeah, we have many different definitions ⁓ of consciousness and I believe many different fields have different definitions. Within your field, how do people usually define consciousness? Yes, indeed it really depends on the field and I would say even ⁓ on specific researcher or clinician. ⁓ When we define consciousness, we like to, I would say, reduce it ⁓ through three components that we call wakefulness, ⁓ consciousness, self-consciousness, self-awareness. and awareness of the environment. And based on those three components, we can ⁓ define the different conditions. So for example, for near-death experience happening in a cardiac arrest, we will ⁓ observe that the person is not awake, is not conscious of the environment, but she is experiencing a complex conscious self-awareness with this ⁓ complex, near-death experience. And so, ⁓ we like to use those three components, but there are plenty of other ways to define consciousness, of course. And I would say that if I have to say a more general definition of consciousness, I will ⁓ define it as simply the subjective experience that the person may report. And so, be it ⁓ an emotion or ⁓ observing something or self, being aware of some specific self-awareness. Right, yeah, just being able to experience the feeling of touch or an emotion or a flavor like coelia. Like I said, is endlessly interesting to me. In preparation of this episode, I also came across the term disconnected consciousness. What does that mean? Yes. So ⁓ as I said at the beginning of the interview, when I defined NDE, I used this terminology to define it as an episode of disconnected consciousness, meaning that it's a mental experience that is distinct from the physical environment. And so, for example, when we talk about the dream during sleep, we can also define dream as a disconnected consciousness episode, even if of course they are not the same as mirrorless experience, but it's the same kind of ⁓ way to define this condition. Right. Okay. Okay. So that makes sense. Yeah. I see that. So you are experienced. You are experience a form of consciousness. You are doing something in a dream. You're driving, you're walking, you're visiting friends, whatever. can be literally anything. Usually it doesn't make much sense. There is an experience going on, but you are not actually doing that. You're just in your bed, presumably. Yes. Okay. Okay. ⁓ And yeah, I think, ⁓ ⁓ What would be interesting to know is ⁓ what are some of the things that we currently do not understand about ⁓ near-death experiences and that we would love to know? What is the holy grail of understanding NDEs? Yes, it's a good question because indeed so far we talk about what we know and some specific hypotheses, but... It's worth mentioning that even the Neptune model I was talking about at the beginning, this complete model is actually partly not yet empirically demonstrated. it was half of the model is based on hypothesis that we have to empirically test. And so ⁓ I think that there are of course a lot of ⁓ unanswered ⁓ questions that remain open regarding NDE and more generally consciousness. Notably, it's still difficult to explain some specific features such as ⁓ precognition, which is the fact to sometimes report during NDE the experience of a future event. ⁓ that will happen later. So all those kinds of features are difficult to explain. And I think that more generally, ⁓ researchers, even out of the scope of near-death experience, are still this difficulty to explain consciousness ⁓ simply. ⁓ And so this is all about the hard problem of consciousness, where today, even if we have good evidence of how the brain and our body is functioning, we still have difficulty to properly explain how human consciousness arises, how we link this subjective experience to the neurophysiological, neurochemical activity from the material. And so I think that's ⁓ of course ⁓ a big question. ⁓ Yeah, it's still a lot to be explored. I'm very curious to hear, compared to when you first started studying ⁓ NDEs compared to now, ⁓ how has studying them changed your view about what's happening? Well, that's a difficult question because it has been like 12 years I'm studying the phenomenon. Yes. To me, the main thing I think that I learned when studying ND is that ⁓ ND, but also maybe other phenomenon, can highlight something that I find kind of remarkable ⁓ about human physiology and human consciousness. To me, it's all about our extraordinary capacity for adaptation. ⁓ And so even when the body and the brain is pushed into condition that seems ⁓ incompatible with normal functioning, at least ⁓ at first glance, ⁓ individuals can nevertheless report experience that are so vivid, so structured and deeply meaningful. And so that's why I'm so passionate by this question. Yeah. No, it's a great answer. And is there something that most people who aren't in the field, people outside of the science usually get wrong about ⁓ near-death experiences that you would want to You mean what ear, sorry. Yeah. So maybe people, is there like a misunderstanding that a lot of people have about what's actually happening during a near-death experience? Well, I think that it's changing, I think it's still sometimes, ⁓ I will restart. I think that there is indeed something that is sometimes still less, not very clear about this phenomenon is that this dissociation between clinical versus brain death. Because people say, well, we experience ND when we die. Well, actually it's It's not true. Well, maybe, but so far we don't know because we don't know what happened after this, right? And so people who were born NDE have actually been in a condition that we call clinical death, meaning that the earth stopped, but the condition was still reversible. While when we talk about brain death, we talk about a near reversible ⁓ condition where actually so far at least we don't know what what humans can experience while ⁓ dying and while ⁓ being in this brain death condition. And I think this is a very important distinction to do because ⁓ this will permit the general public to understand the phenomenon and consciousness. more generally better. Yeah, it's exactly the mistake I made about 10 minutes ago. ⁓ So I'm happy I'm not the only one. I'm happy I'm not the only one. ⁓ Is there ⁓ anything before we ⁓ close the conversation today that you think is still very important to mention or something that you would like to emphasize? I think that with all your questions we were ⁓ ⁓ complete. However, if I may, I may add that I am still ⁓ searching for people who experience NDEE. We have like a database of more than 2000 ⁓ experiencers, but we would like to have more. So if you have, if you listen to us and if you have experience with NDEE and would like to share your experience, don't hesitate to contact me. Plus also, if I may, are also actively trying to find funding for this research. ⁓ That is actually hard to find funding for that, at least in the classical funding institutions. So if you have anything to share as an idea to find funding, don't hesitate to contact me. I'm so glad you brought that up. Yeah. So where can people go if they want to? contact you and also keep up with your work and perhaps be part of the work? Yeah, so I have my email address that I can share. it's cmarschall.be. ⁓ You can actually, I think, it ⁓ easily on Google. I also have my Instagram account, which is cmarschall.be. Simply there I'm trying to feed up the news, etc. Okay, perfect. I'll make sure to put all of the information in the show notes. And yeah, thank you so much for today, Charlotte. I thought it was incredibly interesting. I learned a lot and I think it's a very important topic that more people should know about. Thank you for today and yeah, like I said, I'll make sure to ⁓ guide everyone towards your pages so they can hopefully also be a part of it. Thank you very much.