The discussion now turns back to the question of subtle consciousness. The tantric systems of physiology that are important in Tibetan Buddhism recognize manifestations of subtle consciousness in deep, nondreaming sleep, and in other states including orgasm. These are seen as opportunities to familiarize oneself with subtle consciousness in preparation for its manifestation at death.
The long-standing confusion surrounding the term subtle consciousness begins to clear in this discussion. Tibetan Buddhism understands a broader range of meaning in the term consciousness than Western science, and subtle consciousness in particular may include mental activity that occurs in the realm that Western science classifies as subconscious or even during states which we normally consider unconscious.
DALAI LAMA: In a certain body of Buddhist treatises known as tantra, there is one called the Kālacakra Tantra. A theory of this system identifies the following four states: the waking state, the dreaming sleep state, the nondreaming sleep state, and, finally, the orgasm. There is a kind of physical substance in the body, called “drops,” associated with each of these four states, and each of those four kinds of substances has its specific source and location within the body.
You have established the relationship of brain states and functions with certain mental states, specifically the waking state, the dreaming sleep state, and the nondreaming sleep state. But, so far, we have not discussed the mind or brain state relating to orgasm.
In these same tantric treatises there is a lot of emphasis on the state of mind at the point of orgasm. Now there has been some discussion here concerning whether or not subtle states of mind exist. In Buddhism, the subtle state of consciousness is often not manifest, not evident. However, it is posited in these tantric treatises that at the point of orgasm, the subtle awareness then becomes evident. In fact, there are four occasions in which to varying degrees the subtle form of awareness manifests itself: orgasm, yawning, sneezing, and deep, dreamless sleep. In each of these four cases, to varying degrees, the subtle consciousness does become evident. Somehow the consciousness deepens.
ALLAN HOBSON: This is interesting. I would say that both orgasm and sneezing are state-dependent behaviors, and they are subsumed in our way of thinking among the other states. For example, sneezing only occurs in the waking state, and never occurs in sleeping. Orgasm occurs in the waking state, and it can occur in dreaming, but it does not occur in nondreaming sleep. Yawning occurs in the waking state, when one is sleepy.
DALAI LAMA: Do you see any physiological differences in the state of the brain during those four different states?
ALLAN HOBSON: The only work that has been done is in relation to yawning. There is some evidence of changes in the brain associated with yawning. Not very much has been done on orgasm in any state. The incidence of orgasm in dreaming sleep is so low that it is not easy to study. But lucid dreamers are very good subjects for this study because they can induce orgasm at will. It is one of the reasons people enjoy lucid dreaming, because they can have sexual pleasure without a partner, without social consequences.
ANTONIO DAMASIO: There are changes that happen during yawning and sneezing, but brain changes associated with orgasm are much more marked. They have to do with changes in oxygen delivery to the brain associated with changes in breathing patterns, changes in heart rate, sweating, vasodilation, and tremendously complex changes in chemical mediators, including dopamine, serotonin, acetylcholine, and endorphins. There is a tremendous change in a variety of chemical substances that directly affect the actions of neurons in different circuits. So you really can alter consciousness in the broad meaning of the term. Yawning and sneezing occupy much briefer periods.
DALAI LAMA: Do you find a common denominator in these states?
ANTONIO DAMASIO: It would be difficult to give an adequate answer. I believe that the knowledge needed to answer that question is too limited. Certain things come to mind: changes in oxygen delivery and distribution within the brain and vast chemical changes. So at least those two global shifts which can influence brain functions occur in each of the four states.
LEWIS JUDD: There isn’t fully substantial data on these problems. And sneezing, at least, is of quite short duration.
ALLAN HOBSON: That is an important point. States relating to sleep might be said to be tonic in that they endure for long periods of time. In contrast, the first three examples you gave—sneezing, yawning, and orgasm—are phasic events which occur relatively rapidly and are over fairly soon. The neural mechanisms have to reflect that difference.
I should like to understand what, according to the Buddhist tradition, is the state associated with nondreaming sleep? How is it experienced? What are its characteristics?
DALAI LAMA: Within the Buddhist tradition, we don’t speak in terms of the brain but rather of subjective awareness and also energies as these are experienced subjectively. Within that context, a distinction is made between grosser and subtler states of consciousness associated with grosser and subtler states of energy within the body. In deep sleep, the five sensory modalities have become inactive, and correspondingly the centers associated with them have become inactive. These changes are considered relatively gross. They also take place in a sequential process of going into deep, dreamless sleep, with these grosser states of awareness going dormant and the more subtle state of purely mental awareness becoming evident.
In the mind that is untrained in meditative practice, this sequence of the mind becoming more subtle will frequently not be evident. There are eight stages in this process of going into deep sleep. For a mind that is very finely disciplined in meditation, each of those stages will become evident experientially. In relation to the nondreaming sleep state, the dreaming state is understood to be somewhat more gross. And according to certain texts, there are physiological processes that correspond to these different mental states, and these are associated with subjectively experienced energies in the body.
To explain this more elaborately, we need to go into the whole system of channels and energy centers in the body, the chakras. But, without going into that for the time being, it can be said that in the waking state, these energies tend to be drawn into a locus here in the center of the head, at the level of the forehead. In the dreaming stage, these energies will be even more drawn to a point in the throat. In the deep sleep state, these energies are more drawn into the heart. The location is not the physical heart, the organ, but the heart center which is right in the center of the chest.
Certain events are experienced in meditation that seem to corroborate this theory. For example, in meditation, it is possible to bring your awareness into the heart chakra, and sometimes when this happens, the person will faint. On other occasions, the meditative awareness, finely concentrated, may be brought into the area of the navel. And at this juncture, it has been found experientially that heat is produced by such concentration. If you look at the anatomy of the body, you don’t find these chakra points.
ALLAN HOBSON: I would like to come back to the question of the meditation associated with the eight levels of sleep in a trained subject. Tell us, for example, what are the characteristics of the deepest state so we can respond from the point of view of Western science.
DALAI LAMA: I don’t know! Through training, at that deep level, awareness eventually becomes deeper, deeper, deeper. Then, finally, at the deepest experience, breathing stops.
ALLAN HOBSON: In general, I think that our experience is the same. But we must be very careful about the terminology. We distinguish objectively five stages in our formulation: waking and four stages of sleep.
DALAI LAMA: From a Buddhist point of view, the eight stages are associated with the dissolution of the five elements within the body. The five elements are the elements of earth, water, fire, air, and consciousness. Bear in mind, “earth” doesn’t mean dirt, it refers to the solid constituents of the body; water refers to the fluid constituents, and so on. The dissolution of these elements takes place through five sequential states, and there are three more, corresponding to more and more subtle states of consciousness. The eighth is the most subtle.
ALLAN HOBSON: It might interest you to know that in nontrained subjects, when we perform awakenings in the various stages of sleep, we get less and less evidence of conscious experience. In other words, the deepest stage of nondreaming sleep, defined physiologically, is associated in our untrained subjects with very low levels of consciousness. And in 50 percent of the awakenings there is no evidence of consciousness at all. That doesn’t mean that it couldn’t be changed by training the subjects. But the evidence, from the point of view of the brain, is that you would need to provide a lot of training relating to the physiology.
THUPTEN JINPA: I think there is a certain misunderstanding of this term consciousness. In the Western philosophical or psychological term, consciousness is conscious, whereas, when Buddhist translators use the term, it has a wider meaning. It includes both the subconscious and unconscious levels as well.
ALAN WALLACE: The terms conscious and unconscious are not used in Buddhism. Rather, one speaks of differing degrees of clarity and subtlety of awareness. Even when someone has fainted, for example, and is regarded, in Western terms, as unconscious, from a Buddhist perspective a subtle level of consciousness is still present.
DALAI LAMA: As early as the seventh stage approaching deep sleep, you would say that your awareness has declined. That is, the mind is not clearly apprehending anything.
In Buddhist psychology, we refer to sleep as one of many mental factors. There are fifty-one mental factors, among which sleep is one. But it is said that the mental factor of sleep precedes the deep sleep state, meaning the nondreaming state, just as fear may proceed fainting without going into it. Consider an analogy: Once you have fainted, you feel no fear. However, it can be fear that leads to your fainting. So the fear doesn’t go with you into the fainting. Thus, analogously, in the nondreaming deep sleep state, the mental factor of sleep has already passed.
It is a matter of terminology. Just how this mental factor of sleep in Buddhist terminology corresponds to Western terminology remains to be seen.
ANTONIO DAMASIO: I have a question, for clarification. When you have the very subtle consciousness that one is supposed to have just before death, that really does not mean that you have heightened, greater awareness, but rather the contrary. It means that in fact you are reducing perception to very low levels, right?
DALAI LAMA: Yes.
ALLAN HOBSON: That is very important.
PATRICIA CHURCHLAND: I had assumed exactly the reverse.
ANTONIO DAMASIO: I also had the opposite idea.
DALAI LAMA: One of the purposes of tantric meditation is to prepare you to be able to utilize the death opportunity. The point is to transform that stage of mind into wisdom, because it is the most subtle state of the mind. There is less influence of conditioning, so it is more pure.
ANTONIO DAMASIO: Mental exercise in preparation for death.
DALAI LAMA: Yes, it is very strong.
LARRY SQUIRE: Certainly, modern neuroscience is very sympathetic to the importance of the unconscious. The specialization and differentiation of the brain tells us that things are going on sometimes automatically, or sometimes in ways that we just don’t have access to, given that we are using language mostly for our understanding as well as communication.
This is dramatically brought out in experiments with patients who have had the two halves of their brains separated surgically. In those people you can show that the right side of the brain can be getting information and doing things that the left side of the brain, which is the speaking half of the brain, does not understand. The left side may then make up things, confabulate, to explain behavior for which it cannot see the origins.