In the past entry we examined how “out-of-body experiences” (OBEs) might have an influence in the belief in a “soul” separated from the body. Now we shall take a look to the other two types of “abnormal” psychological experiences that are surely related to that belief: “near-death experiences” (NDEs) and “mystical experiences” (MEs).
Near-death experiences can, to some extent, be considered as a subclass of OBEs, for in them it is common that the subject perceives that she “abandons” her physical body; but this is not completely necessary to have a NDE, and there are other peculiar and interesting features (besides the proximity to death, of course) that make NDEs sufficiently different from OBEs to consider them as a different category. According to the few existing reliable statistics on the topic, it seems that between 6 and 12 per cent of the patients that have recovered from a cardiac arrest in a hospital report having had something like one of those experiences 1. It fact, it also seems that one of the most frequent factors leading to a NDE o an OBE are situations of big physical or psychological stress (e.g., loss of oxygen and heat in alpinists), and being closer to death must certainly be very stressful. NDEs, however, typically include other additional phenomena, like the famous feeling of traversing a tunnel, the meeting with dead relatives, the vision of the past life, the encounter with a “being of light”, and experiencing a feeling of deep serenity. According to the studies quoted by Nelson, these phenomena only occur together in a small proportion of the cases of NDE, i.e., in most of the cases some the phenomena are usually missing.
For obvious reasons, NDEs are not as easy to replicate in a laboratory as OBEs, and as a consequence, our scientific evidence about them is much more anecdotic and not reliable. In spite of this, there is a particular field of scientific experimentation that has contributed to understand, partially at least, what happens in the brain during a NDE: the studies about gravity induced loss of conscience (G-LOC), a typical training procedure in the case of astronauts and Formula-1 pilots, performed in the machines known as ‘centrifuges’, in which several g are reached (g is the standard acceleration of gravity at the earth surface: 9,81 m/s2). It has been confirmed that forces of 5 g kept during more than one minute make most experimental subjects faint, i.e., loss conscience. Experiments performed with centrifuges since the 90’s showed that about 60% of those subjects that fainted, also reported some type of hallucinations during the time they were unconscious, or within the brief period between consciousness and unconsciousness, and these reports were incredibly similar to the typical NDEs, including the perception of OBEs. Observing the brains of these subjects led to the suggestion that this type of experiences are caused by a sudden loss of oxygen in the brain (what is what happens in a cardiac arrest). In particular, blood starts to leave the retina from its periphery, what surely is what creates the well known “tunnel vision”. Furthermore, lack of oxygen in the limbic system induces loss of consciousness, a state similar to lucid dreams (dreams in which one is conscious of being dreaming), chance visions coming out of memory, and also the feeling of deep calm that usually comes with these experiences. It seems, hence, that near-death experiences can be a totally natural phenomena, not connected with the real “separation” of body and soul.
Lastly, mystical experiences (MEs) are much less frequent and phenomenologically rather different from OBEs and NDEs, though the former can be in some cases be united to some of the latter. In spite of their much smaller frequency, it is very likely that MEs have historically had a bigger influence in the development of religious ideas, because for the people experiencing them they are usually a very strong motive to communicate them through literature, theology, or by the creation of religious movements. According to the philosopher and psychologist William James, in his classic book The varieties of religious experience (1902)2, the main features of a ME are the following four:
- Ineffability: the contents of a ME cannot be expressed through ordinary language.
- Noetic quality: MEs are not experience as a mere subjective feeling, but as a kind of knowledge about the depths of being.
- Transiency: MEs tend to be extremely brief, though while the subject is experiencing them, she can feel that “time stops”.
- Passivity: The self seems to dilute and remain in a kind of absolute dependence from some kind of superior being.
I would like to add to the list another important feature: contrarily to OBEs and to NDEs, mystical experiences are not hallucinations, properly speaking; i.e., they are not a distorted perception of reality, in which the subject sees things that do not exist, or see them as they are not; MEs are, rather, a kind of radically different perspective of reality, not necessarily fake, but just abnormal. A totally different thing is that the intellectual interpretation the subjects give of their experiences after experimenting them may lead them to the conclusion that what is perceived during a ME is a being similar to the ones that are protagonists of one or other religious tradition (for example, Catholic mystics often report having seen the Virgin Mary or Jesus Christ, though Muslim or Buddhist mystics rarely provide such an interpretation of their visions), in spite of the fact that most of the content (‘abstractly described’, so to say) of the MEs is remarkably similar in the reports of mystics from all religions, and even from agnostic or atheist people, that also have this type of experiences.
The neurologist Kevin Nelson, that I have already cited, suggests that MEs are also triggered by some neural process in which the limbic system is involved, in this case not because of lack of oxygen, but by other chemical, physical or biological causes: chemical ones would be supported by the similarity with the experiences induced by some drugs, like mescaline, psilocibyn, or LSD; physical reasons may involve the intervention of strong magnetic fields; biological causes are suggested by the fact that MEs are usually associated to epilepsy, and hence, to alterations in the temporal lobe (the area just behind the ear). What I find more interesting in the interpretation that Nelson offers of MEs is that probably these experiences do not actually lead the subject to a “deeper” state of consciousness, or to the perception of a “deeper layer” of reality, but perhaps they simply reveal a more primitive (so to say, “animal”) state of consciousness than our ordinary mode of being. In other words, MEs would make subjects to perceive the world in a way more similar to the one in which “pre-verbal” animals do usually perceive it, animals that probably also lack a “sense of the self” as developed and intense as the one we have. This would, according to Nelson, all the properties of MEs listed by James. However, the experimental study of MEs is obviously difficult, and it is very probable that future investigation brings a lot of surprises.