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Abstract
Table
of Contents
Part I
Part II
Part III
Part IV
Part V
Part VI
Part VII
Part VIII
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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.
 pg
1 of 8 
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.
pg.2
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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.
pg.3
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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.
pg.4
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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.
pg.5
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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.
pg.6
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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.
pg.7
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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.
pg.8
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Copyright © 1988 Evelyn White. All rights
reserved
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