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Abstract

Table of Contents

Part I

Part II

Part III

Part IV

Part V

Part VI

Part VII

Part VIII


     

Part VI: The Subconscious and Forgiveness of Sins

Chapter 2

What Can Be Erased and How?

     THE RESISTANCE OF memory to erasure by various experimental techniques is almost unbelievable. In fact, Ralph Gerard said that the brain of an animal can be so mutilated without apparently disturbing its memory of learned behaviour that it almost looks as though the skull might be filled with cotton batten for all the difference it makes how you poke at it. (16) Furthermore, the things which a dog has once learned to do it does not forget, even if it is robbed of its cerebral cortex altogether! (17) So can one erase memory at all?
     In one series of experiments performed by Gerard, hamsters were trained to run a maze to reach a source of food. Once they had memorized the proper course, various treatments of shock and surgery were employed to make them forget, but without success. Even more remarkable were experiments carried out with white rats which subsequently underwent the most severe cerebral mutilations imaginable. Incisions were made in the brain tissue itself in every conceivable direction, deep and long. Just to see the diagram of these incisions would convince anyone unfamiliar with the results of these experiments that the animals could not possibly have survived such operations. Yet the extraordinary thing is that not only did the rats survive, but there was no measurable impairment of memory. Dr. Gerard comments:
(18)

     Large sections of nearly any part of the brain can be destroyed without loss of particular memories, or, indeed, without disturbance of the memory function. Human brains have been extensively damaged by trauma, tumors, abscesses, by loss of circulation, operative removal, or by shriveling away in extreme age. . . . Yet the recollection of the past experience is likely to remain reasonably intact.

16. Ibid., ref.15, p.118-126.
17. Langer, Susanne, Mind: An Essay on Human Feeling, vol.1, Johns Hopkins Press, Baltimore, 1967, p.438.
18. Gerard, Ra1ph, ref. 15, p.124.

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     One might reasonably ask whether the seat of memory is really resident in the brain at all. It can hardly be questioned that the brain is necessary for the initiation of mind, but we may legitimately ask whether the brain is necessary for the continuance of mind once initiated. I am not suggesting that mind exists entirely apart from the body to which it belongs, for even from the Christian point of view it is clear that the resurrection of the body implies that it fulfills a significant role in the hereafter, as it does in this life. So one cannot positively assert that, once generated through the agency of a brain, the mind can thereafter function with full competence independently of it. There may be some independence, some functions performed with competence, but not entire independence which would allow all its functions to be performed. A body is required even in the world to come. Viktor E. Frankl, during a discussion in the Alpbach Symposium of 1968 made the following pertinent observation: "My contention is that the physiological basis does not cause anything mental, but it does condition it, and there is a great difference between causing and conditioning." (19)
     The usual interpretation regarding the mechanism of memory as seen by those who think only in terms of physics and chemistry is that there are four fundamental functions which such a mechanism must perform:
(20)

1. The configuration of external and internal stimuli impinging on an organism, which constitute experience, somehow coded into a neural representation (i.e., a nerve impulse equivalent)
2. The storing of this neural representation
3. Access to such stores available in a specific way
4. The retrieved data decoded into neural activity in such a form that it somehow revives the original experience, thus constituting a memory

     The assumption here is that we are dealing with an electro-chemical process entirely dependent upon some complex network of nerve chains. Destroy these, and one destroys their power to transmit and with it the power of recall.
     The complexity of this postulated network is almost beyond conception. It is estimated that 15 trillion impressions can be stored precisely and recoverably in an organ composed of perhaps at least 10 billion nerve cells. If we were to allot only one recollection to each cell, the brain would have to be approximately 1,500 times as large as it now is.
(21) Moreover, a real problem in the present context stems from the

19. Frankl: in Beyond Reductionism, edited by Arthur Koestler & J. R. Smythies, Hutchinson, London, 1969, p.254.
20. John, E. Roy, Mechanisms of Memory, Academic Press, 1967, reviewed by J. Z. Young in Nature, Dec. 23, 1967, p.1247.
21. Gerard, Ralph, ref. 15, p.118.

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fact that an estimated average of 30,000 nerve cells die in the cortex every 24 hours. (22) Yet a middle-aged individual having already lost about a half-billion cells can not only learn as well as a twenty year old but under the proper conditions can also recall just as well.
     Thus the question arises as to how cells which have received a message and tucked it away in coded form (if current theory is correct) can die off and leave the coded message intact and recoverable.
     Sometimes light is thrown on this kind of problem by studying the situation in the simplest possible form. Instead of experiments with a brain which has the complexity of man's, we can experiment with some simple creature that might be said to have no brain at all. Such a creature is the humble planarium flatworm. It has an exceedingly simple central nervous system distributed down the length of its body, with very little to indicate the head-end except the existence of two little bodies called ganglia. In higher forms the ganglia are quite distinct from the brain itself. The extraordinary thing about this little creature is that if it is chopped in two, the tail-end will form a head and the head-end will form a tail for itself. Now, these simple forms of life have been shown very clearly to have some kind of memory. This is demonstrated by the fact that, like all other animals, they must eat to live but tend to lose their appetite a little bit and for a little while when they are put into a strange environment.
(23) In short, as Ardrey has rightly observed, they know when they are in home territory and are upset when they are surrounded by what is unfamiliar. (24) It is generally conceded that this exhibits memory; that is, a memory of the familiar surroundings which can be "kept in mind," and compared and contrasted with the unfamiliar which is thus felt to be disturbing.
     Further experiments with these creatures have shown that they could quickly learn to avoid a situation which resulted in an unpleasant experience. Moreover, when one is chopped in two and recovers its wholeness again as two separate individuals, both pieces "remember" without having to be re-educated. As a matter of fact, a planarium can be cut up into at least 6 segments, each of which is capable of regenerating into a complete animal and each of which preserves its memory intact.
(25)
     A great deal of excitement in the scientific world arose by the discovery that these much chopped-up little animals can in fact be

22. Penfield, Wilder, ref.11, p.155.
23. Best, J. B. and Irvin Rubenstein, "Environmental Familiarity and Feeding in a Planarian," Science, vol.135, 1962, p.916-918.
24. Ardrey, Robert, The Territorial Imperative, Dell Publishing Co., New York 1966, p.327.
25. Koestler, Arthur, The Ghost in the Machine, Hutchinson, London, 1967, p.212.

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turned into mincemeat and fed to other planaria which appear to acquire memories from this "diet," memories which belonged not within their own experience but the experience of their dinner. (26) This really seems to indicate that memory is exceedingly diffuse, and though it may have always been initiated by the brain, it is thereafter sustained somehow by every part of the organism as a whole. It is true that scientists hypothesize that the memory is somehow stored chemically in molecules of ribonucleic acid (RNA) and that all that is transferred is a specially structured fragment of material substance and nothing more. And it is true that some scientists question the validity of the "chopped up planaria" experiments altogether. But the experiments have been repeated by others, and there seems little reason to doubt the validity of the results any more. (27) So perhaps we must conclude from this evidence that in simple forms of life, mind is resident rather specifically in the whole of the animal. As we move up the scale of complexity this total identity is gradually reduced until we reach man, where almost complete independence is evident. Of these planaria J. B. Best wrote: (28)

     If one finds that planarian behavior resembles behavior that in higher animals one calls boredom, interest, conflict, decision, frustration, rebellion, anxiety, learning and cognitive awareness, is it permissible to say that planarians also display these attributes?
     Suppose the apparent similarity between the proto-psychological patterns of planarians and the psychological patterns of rats and men turns out to be more than superficial. This would indicate that psychological characteristics are more ancient and widespread than the neurophysiological structures from which they are thought to have arisen. . .

     In other words, the seat of memory may in fact exist before the brain has even formed as an identifiable organ. Thus Best suggested that perhaps "memory" is everywhere, in every cell, as it were, dispersed throughout the whole organism: (29)

     Such patterns may stem from some primordial properties of living matter, arising from some cellular or sub-cellular level of organization rather than nerve circuitry. . . .

     There is one further piece of evidence which bears upon the

26. John E. Roy, ref.20, p.1247.
27. Jacobson, Allan L., C. Fried., & S. Horowitz, "Planarians and Memory," Nature, vol.209, 1966, p.599-601. See also G. Unger and L. N. Irwin "Transfer of Acquired Information Brain Extracts," Nature, vol.214, 1967, p.453-455.
28. Best, J. S., "Diurnal Cycles and Cannibalism in Planaria," Science, vol.131, 1960, p.1884-85.
29. Ibid.

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problem of animal memory, suggesting that memory will not be lost when its particular "storage bin" is destroyed, provided that some contralateral part of the brain capable of doing double duty remains intact. In a paper entitled "Central Nervous System: Recovery and Function," Donald G. Stein and co-workers found that if a particular area of the brain is necessary for the control of a behaviour sequence, its removal in a single operation appears to destroy the memory of the sequence. (30) But if the same area is removed in stages with time for recovery of the animal between each operation, the memory of the learned behaviour sequence is not destroyed. In other words, a succession of cortical lesions has no effect upon retention of learned discrimination under certain conditions, whereas a single operation in which the same total effect is induced at one time produces a marked deficit in performance. The authors wrote: (31)

     In our experiments sequential removal of cortical and sub-cortical associative areas of the brain did not render the animal different from normal . . . controls with respect to performance on a variety of tasks.
     In contrast, rats with single stage lesions (i.e., all at one time) at the same places showed marked and long standing deficits on these tests of learning and performance. Since no training intervened between first and second stages of the operations in the two-stage (or sequential) groups, and since all animals were handled in the same manner, the apparently normal behavior of the two-stage animal must be due to some naturally occurring re-organization of activity of the central nervous system.

     As Stein rightly observes, the explanation of this ability of the nerve cells somehow to transfer their learning "after" they have been removed suggests that what was remembered was not actually encoded in those particular cells in the first place.
     If memory is diffuse in this sense, then it is naturally exceedingly difficult to eradicate unless the whole cortex is destroyed. And even this will not always be sufficient, for as we have already noted, dogs which are operatively decerebrate will still remember how to perform tricks learned before the operation. Therefore, Stein observed:
(31)

     Such data would indicate that although a particular structure may be involved in the mediation of certain behavior, its absence [or deliberate removal] would not be a necessary condition for the elimination of that behavior.

     Although the dog's brain may be destroyed experimentally without

30. Bernstein, Donald G., et al., "Central Nervous System: Recovery of Function," Science, vol.66, 1969, p.528-529.
31. Ibid., p.528.


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total loss of memory of learned behaviour, a routine "destruction" is meanwhile occurring at a continuous rate and as a natural process in all brains, as we have already noted, since brain cells are constantly dying throughout life. Samuel H. Baronides in "The Relationship of Biological Regulatory Mechanisms to Learning and Memory" rightly observed: (33)

     One of the puzzling aspects of a memory is its permanent deposition within a nervous system which, except for its presumably immutable neuron DNA, is apparently being degraded and re-synthesized at a fairly rapid rate. The fact that the molecules of the nervous system are subject to the process of "turnover" has necessitated the notion that the molecular change in memory can reproduce itself, that is, can maintain its permanence by some form of self replication.

     It seems necessary to postulate that if memory can be destroyed or expunged by some operative technique, then the actual process of storing it should in some way chemically or electrically effect a change in the cortical substance itself. Admittedly the effect must be tiny, but it should at least be discoverable functionally just as in the electronic circuitry of a computer the effect would be discoverable. But James L. McGaugh has assured us that so far we have no evidence of such a change: (33)

     To a considerable degree research into physiological bases of memory has consisted of attempts to find evidence of some permanent change in neural functioning produced by experience. . . .
     Clear evidence of specific changes produced by specific experiences has so far eluded even the most imaginative researchers.

     Thus the whole question of "erasure" resolves itself into an even more difficult question. It is not merely, What can be erased? but Where is the eraser to be applied in the first place? The evidence at the present time seems to indicate that expurgation is exceedingly difficult if not quite impossible. Ralph Gerard spoke of various treatments, such as electro-convulsive shock, which in spite of their severity vis-à-vis the delicate tissues of the brain, seem quite incapable of destroying memory except under one set of circumstances namely, when the shock is given within a minute of the learning experience -- so that the brain simply did not have time to "fix" the impression. But he said, "In such instances stored experience traces seem [my emphasis] to be expunged, but whether they are really irrecoverable is perhaps not fully

32. Baronides, Samuel H., "Relationship of Biological Regulatory Mechanisms to Learning and Memory," Nature, Jan. 2, 1965, p.19.
33. McGaugh, James L., "Time-Dependent Processes in Memory Storage," Science, vol.153, 1966, p.1351.

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established. Recall alone may be at fault, as in simple forgetting." (34) In a planarium it seems that the whole animal has to be completely destroyed, its very molecular structure scrambled. But we know from Scripture that though our bodies return to their basic elements, the "individual" with all his memories remains in some way fully recoverable to reappear in the life to come as recognizably still the same individual person. That we shall be recognizable is borne out by the rich man's recognition of the poor man in Luke 16:19f., and such recognition means the persistence of memory through death even though death has destroyed the brain.
     Virtually all the experimental evidence thus far reviewed in this Paper is derived from animals rather than from human beings, and therefore it applies primarily to animals rather than man. Indeed, much of this evidence is from only one species of animal (rats), and it must be emphasized that experiments with one species of animal cannot even be applied across the board to other species of animals which are structurally alike, much less to man. Koestler wrote at some length, and eloquently, on what he terms the "rato-morphic view of man."
(35) He felt that the transfer of findings from rats to men is of very doubtful validity. So do others. McGaugh noted this when he said, "In our work with animals we have found no analog of human immediate memory." (36) It takes much longer for a learning experience to be encoded in the brain of an animal than it does for man. For example, a man can repeat back a surprisingly large number of digits immediately after hearing them only once. This power of instant recall has not apparently been found in animals. Thus all these lines of evidence require cautious assessment. This at least can be said: that according to the present evidence, memory is a far more diffuse and a far less organ-tied phenomenon than was formerly believed.
     Memory is by no means analogous therefore to a kind of programmed "recall" which can be built into a computer, with which the brain is being so frequently equated as a mechanism.
(37) In his book The Mind of Man Nigel Calder has a very effective illustration of how different the brain really is from the computer. He wrote: "Despite their enormous speed of calculation and their ability to carry out logical operations at high speed they depend completely on the people who write their programs for all their clever tricks. . . . You may not be much

34. Gerard, Ralph, ref.15, p.119.
35. Koestler, Arthur, ref.25, p.15.
36. McGaugh, James L., ref.33, p.1357.
37. Calder, Nigel, The Mind of Man, British Broadcasting Corporation, London, 1970, p.267.

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perturbed by the fact that their are several mipsprints and other mistake in this sentence but equivalent errors in a computer program could reduce a mighty machine to impotence." We are clearly dealing with a far more complex phenomenon. Roger W. Sperry, (38) in an essay on "Mind, Brain, and Humanist Values," pointed out that where we used to see purpose and meaning in human behaviour, "Science now shows us a complex biophysical machine composed entirely of material elements all of which obey inexorably the universal laws of physics and chemistry." But he felt that when science persuades us to accept such a view of behaviour, it "may have sold society and itself a somewhat questionable bill of goods." Lord Adrian, contributing a leading editorial to Science Journal, devoted entirely to the human brain, says without hesitation, "Our final aim is to bring human behaviour within the framework of the physical sciences." (39) What a frightful goal! Is it any wonder that a younger generation is turning from the sciences.
     All too frequently mind is equated with brain by the chemists, physicists and electronics people, and inevitably by the Public. But I think the evidence points increasingly in another direction because, as we shall see in the next chapter, it is even more difficult to equate mind with brain when one comes to think critically, not merely about the meaning of consciousness, but of self-consciousness
.

38. Sperry, Roger W., "Mind, Brain and Humanist Values," Bulletin of the Atomic Scientist, Sept., 1966, p.243.
39. Adrian, Lord, "The Brain as Physics," Science Journal, vol.3, no.5, 1967, p.3.

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Copyright © 1988 Evelyn White. All rights reserved

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