 |
| Fotografia ravvicinata di un dettaglio di Salvador Dalì, La persistenza della memoria, 1931 |
Il terzo sottosistema per un modello sistemico della coscienza esaminato da C.T. Tart, dopo l'estero-interocezione e l'elaborazione degli input, è la memoria:
Subsystems
Memory
The Memory subsystem is concerned with information storage, with containing residues of past experiences that are drawn upon in the present. Memory is thus a large number of semipermanent changes caused by past experience. We can think of memory as structures, presumably in the brain (but perhaps also in the body structure), which, when activated, produce certain kinds of information. And we should not assume that there is just one Memory; there is probably a special kind of memory for almost every subsystem.
Conventional psychological views of Memory also often divide memory functioning into short-term or immediate memory, medium-term memory, and long-term memory. Short-term memory is the special memory process that holds information about sensory input and internal processes for a few seconds at the most. Unless it is transferred to a longer-term memory, this information is apparently lost. Thus, as you look at a crowd, searching for a friend's face for a short time, you may remember a lot of details about the crowd. Then you find your friend's face, and the details about the crowd are lost. There is no point in storing them forever. This short-term memory is probably an electrical activity within the brain structure that dies out after a few seconds: no long-term structural changes occur. Once the electrical activity dies out, the information stored in the pattern or in the electrical activity is gone forever.
Medium-term memory is storage of from minutes to a day or so. It probably involves partial structural changes as well as patterns of energy circulation. You can probably recall what you had for breakfast yesterday morning, but in a few days you will not remember the contents of that meal.
Long-term memory involves semipermanent structural changes that allow you to recall things experienced and learned a long time ago.
This division into short-, medium-, and long-term memory is of interest because these kinds of memories may be differentially affected during d-ASCs. At high levels of marijuana intoxication, for example, short-term memory is clearly affected, although long-term memory may not be. Thus, a marijuana user often reports forgetting the beginning of a conversation he is engaged in, but he continues to speak English. There is little more we can say about differential effects of various d-ASCs on these three kinds of memory, as they have not yet been adequately studied. They offer a fruitful field for research.
A most important aspect of Memory subsystem functioning in various d-ASCs is the phenomenon of state-specific memory. In a number of studies, subjects learned various materials while in d-ASCs, usually drug-induced, and were tested for retention of these materials in a subsequent ordinary d-SoC. Generally, retention was poor. The researchers concluded that things were not stored well in Memory in various d-ASCs. it is now clear that these studies must be reevaluated. Memory is specific. The way in which information is stored, or the kind of Memory it is stored in, is specific to the d-SoC the material was learned in. The material may be stored, but may not transfer to another state. If material is learned in a d-ASC and its retention tested in another d-SoC and found to be poor, the nonretention may indicate either an actual lack of storage of the information or a state-specific memory and lack of transfer. The proper way to test is to reinduce the d-ASC in which the material was learned and see how much material is retained in that state. State-specific memory has been repeatedly demonstrated in animals, although the criterion for the existence of a "state" in such studies is simply that the animals were drugged to a known degree, a criterion not very useful with humans, as explained later.
There is now experimental evidence that for high levels of alcohol intoxication there is definite state-specific memory in humans. It is an experimental demonstration of the old folk idea that if you lose something while very drunk and cannot find it the next day, you may be able to find it if you get very drunk again and then search. Experiential data collected in my study of marijuana users also indicate the existence of state-specific memory, and I have recently received verbal reports that laboratory studies are finding state-specific memory for marijuana intoxication. There also seems to be state-specific memory for the conditions induced by major psychedelic drugs.
State-specific memory can be readily constructed for hypnosis that is, state-specific memory may not occur naturally for hypnosis, but it can be made to occur. If you tell a hypnotized subject he will remember everything that happened in hypnosis when he comes back to his ordinary state such will be his experience. On the other hand, if you tell a deeply hypnotized subject he will remember nothing of what went on during hypnosis or that he will remember certain aspects of the experience but not others, this will also be the case when he returns to his ordinary state. In any event he will recall the experiences the next time he is hypnotized. This is not a pure case of state-specific memory, however, because amnesia for hypnotic experiences in the waking state can be eliminated by a prearranged cue as well as by reinducing the hypnosis.
Another excellent example of state-specific memory is that occurring in spiritualist mediums. A medium enters a d-ASC in which his ordinary consciousness and sense of identity appear to blank out for a time. He may report wandering in what may be loosely called a dreaming state. Meanwhile, an alleged spirit entity ostensibly possesses him and acts as if it has full consciousness. Upon returning to a normal state, the medium usually has total amnesia regarding the events of the d-ASC. The alleged spirit communicator, however, usually shows perfect continuity of memory from state to state.
I suspect that state-specific Memory subsystems will be discovered for many or most d-ASCs, but the necessary research has not been done. The kinds of state-specific memories may vary in completeness. The ones we know of now—from marijuana intoxication, for example—are characterized by transfer of some information to the ordinary d-SoC but nontransfer of other information, the latter often being the most essential and important aspects of the d-ASC experience.
Ordinarily, when we think of Memory we think of information becoming accessible to awareness, becoming part of consciousness, but we should note that we "remember" many things even though we have no awareness of them. Your current behavior is affected by a multitude of things you have learned in the past but which you are not aware of as memories. You walk across the room and your motion is determined by a variety of memories, even though you do not think of them as memories.
Note also that you can remember things you were not initially aware of. When you scan a crowd looking for a friend's face, you may be consciously aware of hardly any details of other faces, being sensitive only to your friend's. A minute later, when asked to recall something about the crowd, however, you may be able to recall a lot of information about it. For this reason, Figure 8-1 shows a direct information flow arrow from Input-Processing to Memory.
We store in Memory not only things that have been in awareness, but also things that were never much in awareness to begin with.
An interesting quality of information retrieved from Memory is that we generally know, at least implicitly, that we are retrieving memories. We do not confuse these with sensations or thoughts. Some kind of operating signal or extra informational quality seems to be attached to the memory information itself that says "This is a memory." There is an intriguing analogy for this. In the early days of radio, when a newscast tuned you in to a foreign correspondent, there was an obvious change in the quality of the audio signal, a change that you associated with a foreign correspondent broadcasting over a long distance on short wave. The sound was tinny, the volume faded in and out, there were hisses and crackles. This was a noninformational extra that became so associated in listeners' minds with hearing a real foreign correspondent that many radio stations resorted to the trick of deliberately adding this kind of distortion years later when communication technology had improved so much that the foreign correspondent's voice sounded as if he was actually in the studio. The added distortions made the listeners feel they were indeed hearing a faraway reporter and made the broadcast seem more genuine. Similarly, memory information is usually accompanied by a quality that identifies it as memory. The quality may be implicit: if you are searching actively for various things in your Memory, you need not remind yourself that you are looking at memories.
This extra informational quality of memory can sometimes be detached from memory operation per se. It is possible to have a fantasy, for example, with the "this is a memory" quality attached, in which you mistakenly believe you are remembering something instead of just fantasizing it. Or, the quality may be attached in a d-ASC to an incoming sensory perception, triggering the experience of déjà vu, the feeling that you have seen this before. Thus you may be touring in a city you have never visited and it all looks very familiar; you are convinced you remember what it is like because of the presence of the "this is a memory" quality.
When information is actually drawn from Memory without the quality "this is a memory" attached, interesting things can happen in various d-ASC. Hallucinations, for example, are information drawn from memory without the memory quality attached, but with the quality "This is a perception" attached.
Much of the functioning of the Sense of Identity subsystem (discussed later) occurs via the Memory subsystem. You sense of who you are is closely related to the possession of certain memories. If the "this is a memory" quality is eliminated from those memories so that they become just data, you sense of identity can be strongly affected.
Other variations of Memory subsystem functioning occur in various d-ASCs. The ease with which desired information can be retrieved from memory varies so that in some d-ASCs it seems hard to remember what you want, in others it seems easier than usual. The richness of the information retrieved varies in different d-ASCs, so that sometimes you remember only sketchily, and at other times in great detail. The search pattern for retrieving memories also varies. If you have to go through a fairly complex research procedure to find a particular memory, you may end up with the wrong memories or associated memories rather than what you were looking for. If you want to remember an old friend's name, for example, you may fail to recall the name but remember his birthday.
Finally, we should note that a great many things are stored in Memory but not available in the ordinary d-SoC. The emotional charge connected with those memories makes them unacceptable in the ordinary d-SoC, and so defense mechanisms repress or distort our recall of such information. In various d-ASCs the nature of the defense mechanisms may change or their intensity of functioning may alter, allowing the memories to become more or less available.
Finally, we should note that a great many things are stored in Memory but not available in the ordinary d-SoC. The emotional charge connected with those memories makes them unacceptable in the ordinary d-SoC, and so defense mechanisms repress or distort our recall of such information. In various d-ASCs the nature of the defense mechanisms may change or their intensity of functioning may alter, allowing the memories to become more or less available.
sottosistemi del Tao - II
