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Table of Contents

Chapter 1

Chapter 2

Chapter 3

Chapter 4

Chapter 5

Chapter 6



Further Reading


The Mysterious Matter of Mind

Chapter Five

Laying the Experimental Foundations

      One of Sherrington's most notable pupils was the Canadian neurosurgeon Dr. Wilder Penfield. He is best known for his remarkable studies of, and successful treatment of, hundreds of patients afflicted with epilepsy. This work involved surgical exposure and electrode stimulation of brain tissue in fully conscious patients. By observing the patient's reaction as the electrode was moved gently from point to point over the temporal lobe, it proved possible in many cases to locate the area of damaged tissue causing the epilepsy.
     Excising these damaged tissues reduced and sometimes halted the recurrence of fits. An unexpected discovery was the finding that in many cases there was involuntary recall of extremely vivid and often dramatic scenes from the patient's past life, which scenes he or she was able to describe in great detail, being fully conscious of the surgeon's activity. This work was carried out in the Montreal Neurological Institute over a period of thirty years.
     In his training at Oxford under Sir Charles Sherrington

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and for a short period under Dr. Santiago Ramon-y-Cajal in Spain, Penfield absorbed and wholly accepted the principle that all such experimental work must be conducted with the assumption that mind is in the brain, that mind will in due course be entirely explained in terms of physics and chemistry and electrical circuitry.
     At the close of active surgical practice he observed:

     Throughout my own scientific career, I, like the other scientists, have struggled to prove that the brain accounts for the mind. But now, perhaps, the time has come when we may profitably consider the evidence as it stands, and ask the question: "Do brain mechanisms account for the mind?" Can the mind be explained by what is now known about the brain? If not, which is the more reasonable of the two possible hypotheses: that man's being is based on one element, or on two?

     This shift in point of view was not made easily. In 1950 Penfield outlined briefly but eloquently an entirely mechanistic interpretation of the brain's functioning. But subsequent evidence gradually convinced him that this mechanistic and monistic view did not adequately account for the facts. He wrote subsequently, "Something else finds its dwelling place between the sensory complex and the motor mechanism. . . .  There is a switchboard operator as well as a switchboard." (50)
     In his Mystery of the Mind, there is a frank discussion of the thoughts which went continually through his mind as he probed the brain tissues of epileptic patients in the search for root causes. He wrote that, while agreeing with Lord Adrian that we must always guard against introducing ideas into our science which are not part of science, yet we must subject our research to our own speculation at times and that, where we do, critical evaluation is still possible.
     He then describes very briefly the procedure which he came to adopt in the operating room and the rationale behind it. The object was to locate, in epileptic subjects, the cause and location of the point of irritation of the neuron bombardment which is the trigger of the epileptic fit, and, having precisely located it, to excise the tissue in that area. The procedure

49. Penfield, Wilder, The Mystery of the Mind, Princeton University Press, 1975, p.xiii.
50. Penfield, Wilder, The Physical Basis of Mind, edited by P. Laslett, Oxford, Basil Blackwell, 1950, p.64.
51. Penfield, Wilder, The Mystery of the Mind, Princeton University Press, 1975, pp.4—5.

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was found to be successful in hundreds of cases without further ill effect, provided that only one hemisphere had been damaged. The contralateral tissue in the other hemisphere (when the triggering site lay in the temporal lobe) was able to take over the function of the excised tissue. (See Figure 2 for area identity.)

Figure 2. Showing the relation of the
temporal lobe to the rest of the brain.

     Penfield said further that, for safety's sake and a fair likelihood of cure, the surface of one hemisphere of the brain needs to be bared extensively in order to study and possibly excise a damaged part. This operation was considered less dangerous and more helpful if the patient was conscious and alert during the entire procedure, so only a local painkiller was injected into the patient's scalp. Penfield emphasized that a great amount of doctor-patient trust and communication were necessary to make such an operation both successful and humane. (52) This procedure sometimes revealed the site that caused epileptic seizures by triggering one.
     To the layman, it seems an awesome undertaking. But the secret of success depends on the patient's being able to tell the surgeon what his conscious experience is as the operator explores the exposed cerebral tissue with the electrode. [A single contact point is used, carrying a 60-cycle 2-volt current.] Without this, the only guide to the surgeon would be spasmodic and involuntary muscular

52. Ibid., p.12.

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movements. Since the stimulation of the temporal lobe does not produce such movements, only the conscious patient can tell the surgeon of the effects of exploration. (See Figure 3 for map of motor-control areas).

Double Consciousness

      This has produced the surprising and remarkable experience in the subject of a form of double consciousness, as Penfield termed it. The patient is not only fully aware of his immediate surroundings, operating room, the surgeon and his assistants — whole local scene in fact — but also of the suddenly re-enacted scene from the past, a scene so vivid that it includes sounds, and in one case even included the odour of coffee being brewed!
     He records one such occasion in which "a young South African patient lying on the operating table exclaimed, when he realized what was happening, that it was astonishing to him to realize that he was laughing

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with his cousins on a farm in South Africa, while he was also fully conscious of being in the operating room in Montreal." Penfield observed: "The mind of the patient was as independent of the reflex action as was the mind of the surgeon who listened and strove to understand. Thus, my argument favours independence of mind-action." (53)
     Penfield was thus driven to conclude that the stimulus of the electrode was responsible in effect for a kind of TV program which the subject was watching objectively, while the subject's own mind was directing the production of an equally complete record of the events occurring in the room around him. Just as we can objectively watch a TV program in the company of others whose presence we are fully conscious of, so here were two different kinds of consciousness. The mind was observing by its own will a program presented to it mechanistically by electrode stimulation much as the TV operated independently of the viewer. As Penfield put it, if we liken the brain to a computer, man has a computer, not is a computer.
     This discovery was totally unexpected. But it was in no way singular. It was repeated again and again for hundreds of patients, each of whom could identify the scene recalled with ease and virtually instantaneously. Patients could elaborate on what they saw and explain the circumstances, much as a TV viewer seeing a serial program might explain the circumstances to a watching companion who was ignorant of the previous events. In such a situation there are clearly two elements. The viewer is not part of the TV program but an observer. Yet he is more than an observer insofar as the viewer can adjust the set, clarify the image, change the program, and (in a recall situation) shut it off at will under normal circumstances by a shifting of attention (i.e., turning to another program). Here, then, we have a dualism of object and subject, of brain and mind.
     It is no longer safe to view the mind as a computer, though the brain is indeed a computer of extraordinary refinement. But this computer has a programmer and an operator who is using it as a tool of recall and of motor control.

53. Ibid., p.55.
54. Ibid., p.108.
55. Ibid., p.40.

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Supervisory Control by the Mind

      Epileptic subjects may sometimes experience total "blackout" as to consciousness, the mind apparently ceasing entirely to control the brain. Provided that the brain has already been programmed, the subject becomes an automaton and completes it in a state of total mindlessness. Patients may even complete a journey from work by car. Provided the journey is a habitual one and that no unexpected interference occurs, navigating the traffic and road turns is done by means of purely conditioned reflexes; afterwards nothing whatever of the journey will be recalled. The efficiency of the brain as a computer is truly remarkable. Penfield observed that the continual functions of the normally active mind were apparent in such journeys. (56) But he emphasized that it is the mind that must first program the computer brain, sin computer is only a thing and, on its own, has no ability to make totally new decisions for which it is programmed. (57)
     Wonderful though the brain is as a computer, we see its limitations and its dependence upon the conscious directives of the mind for purposeful levels of activity normal to human life. It is indeed something the individual possesses but not something that possesses the individual.
     Penfield was led to believe that only what the mind has "attended to" is apparently programmed into the brain.
(58) If the subject has walked through traffic, consciously observing avoidance patterns for maintaining his own safety, this motor activity will be programmed in the computer automatically and in the event of epileptic automatism the subject, though wholly unconscious, will still navigate safely through traffic unless some previously unexperienced complication arises. Penfield described the normally healthy person as an individual who goes about his world constantly depending on his own personal computer which he programs to fit into his own continually changing objectives and concerns. (59) *

56. Ibid., p.45.
57. Ibid., p.47.
58. Ibid., pp.39-40, 58-59.
59. Ibid., p.61.
*It should, however, be noted that under hypnosis some recall of details that are only with difficulty attributed to attentive observation in the past is possible. For example, under hypnosis a man drew accurately every lump and grain on the top surface of a brick he had laid in a wall twenty years before. Since his trade was bricklaying, it is difficult to believe he consciously attended to the surfaces of each brick he laid day by day. Ralph Gerard. who reported this instance, in which the accuracy of reporting was verified because the building was being demolished, observed, "Men remember and recall innumerable details never consciously perceived" ("What is Memory?" Scientific American, September 1953, p.118). It seems unlikely that we consciously perceive all that idly strikes our senses. But there is no way of knowing this. Possibly the past is not recoverable in its entirety if only because we would need a second lifetime to recover it, and much of it is worthless.

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     Penfield made many surprising discoveries about the potential of temporal lobe exploration in this way. A particular site when contacted by the electrode produces a specific recollection. It is so specific that the re-lived experience begins always at precisely the same point in the sequence of events. There is not a continuation where the last scene finished off, but a repeat performance. In one subject this occurred sixty-two successive times! (60) This seems to indicate a very specific localization within the cortex, like setting the needle down in the same spot on a record. (See Figures 4 and 5)
     However, it was not always so. One subject, stimulated in the same area, had four apparently unrelated experiential responses. First he heard "footsteps"; secondly, "a company of people in the room"; thirdly, "like being in a gymnasium"; and finally, "a lady talking to a child at the seashore."
(61) In the case of repetitious recall, nothing has been lost, nor has anything been added. As Penfield says, "Events are not a bit fancifully elaborated as dreams are apt to be when recalled." (62) And again, elsewhere, Penfield wrote: (63)

     The vividness or wealth of detail and the sense of immediacy that goes with its evoked responses serves to set them apart from the ordinary process of recollection which rarely displays such qualities. Thus with stimulation at Point No. II in subject J. V. (Case No. 15) the patient said, "There they go — yelling at me. Stop them!"

     The individual is able consciously to identify the meaning of the re-lived experience not as a kind of hallucination but as something as real as life from which he nevertheless stands apart. A woman listening

60. Penfield, Wilder and Phanor Perot, "The Brain's Record of Auditory and Visual Experience: A Final Summary and Discussion," Brain, vol.86, part 4, December, 1963, p.685.
61. Ibid., p.682.
62. Penfield, Wilder, "Epilepsy; Neurophysiology and Some Brain Mechanisms Related to Consciousness," in Basic Mechanisms in Epilepsies, edited by. Jasper, Ward, and Pope, Toronto, Little, Brown, 1969, p.796.
63. Penfield, Wilder and Phanor Perot, "The Brain's Record of Auditory and Visual Experience: A Final Summary and Discussion," Brain, vol.86, part 4, December, 1963, p.679.

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to an orchestra under Penfield's stimulating electrode hummed the tune she heard, verse and chorus, thus accompanying by an act of conscious effort the very music which was being recalled so vividly. Such recallings were entirely involuntary. They are not memories voluntarily brought to the surface. They are detailed and more vivid than such memories ever are. Penfield reports the experience of one patient who experienced an occasion on which she was sitting in a room and listening to the children playing outside. The sounds of motor traffic and all the other noises of urban living provided the "natural" background. She discussed all this with Dr. Penfield while it was happening, and so real was the experience that it took some time to convince her afterwards that he had not actually arranged the whole thing, including the noises outside at the time. Needless to say, he had not done so. (64)
     Sometimes the re-lived experience is so complex that the patient has to explain the background of it later. One 23-year-old woman re-lived what she called a "fabulous" event when she smashed a plate at dinner with her elbow and tremendously enjoyed the experience!
(65) She wanted to explain why she so enjoyed it. Another patient suddenly found herself sitting in the right-hand rear seat of a car, with the window slightly down, waiting at a level crossing for a train to pass. She could even count the train cars as they went and all the characteristic sounds and noises were there. After the train had passed and they crossed the tracks into town, even an old familiar smell was experienced — the odour of brewing coffee. Penfield says this was the only case of a re-experienced smell he came across in over a thousand patients whose brain surface was exposed in this way in an effort to locate the cause of epileptic attacks. (66)

Figure 5. Summary maps to indicate where,
in the two cerebral hemispheres,
experiential responses of all types
were produced by electrical stimulation.

64. Ibid., pp.645—46.
65. Ibid., p.643.
66. Ibid., pp.648—49.

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Figure 4. Diagram of the brain of one of Penfield 's epileptic patients. (Top: right hemisphere, side view; bottom: right hemisphere, bottom view.) The letters A-F identify points on the brain stimulated by means of an electrode. The verbal responses of the patient to such stimulation are given below.

Reaction of patient upon contact at individual points as shown in Figure 4.

A: "I heard something, I do not know what it was."

A: (repeated without warning) "Yes. Sir, I think I hear a mother calling her little boy somewhere. It seemed to be something that happened years ago." When asked to explain she said, "It was somebody in the neighbourhood where I live." Then she added that she herself "was somewhere close enough to hear."

B: "Yes. I heard voices down along the river somewhere — a man's voice and a woman's voice calling. . .  I think I saw I river."

C: "Just a tiny flash of a feeling of familiarity and a feeling that I knew everything that was going to happen in the near future."

D: (a needle insulated except at the tip was inserted into the superior surface of the temporal lobe, deep in the fissure Sylvius, and the current was switched on) "Oh! I had the same very, very familiar memory, in an office somewhere. I could see the desks. I was there and someone was calling to me, a man leaning on a desk with a pencil in his hand."

I warned her I was going to stimulate, but I did not do so. "Nothing."

E: (stimulation without warning) "I had a little memory someone in a play — they were talking and I could see it — I was just seeing it in my memory."

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     Penfield found that if the cortical area which had been the site of stimulation for the re-living of some experience was subsequently removed surgically (when it was believed to be for the benefit of the epileptic patient), the patient could still voluntarily recall the experience afterwards. Evidently the memory itself was not at this point but was stored in some area to which the site was connected. Cutting the connection made it impossible to obtain recall by electrical stimulation, but it did not eradicate the memory itself which could still be recalled voluntarily.
     Penfield was forced to conclude that, while he had spent years trying to explain the mind totally on the basis of brain-action, his years of study made it far simpler and more logical to explain mind and brain as two basic elements instead of one. This proposition seemed to offer the best path to lead scientists to a final understanding of the brain/mind issue. He believed it would never be possible to explain the mind from neuronal action within the brain, since the mind seems to develop independently throughout a person's life as if it were a continuing thing and since a computer, which the brain is, must have a controlling agency capable of independent comprehension.
     Penfield has never suggested that mind can get along without the brain, though clearly brain can continue for some time without mind, as it does in epileptic automatism. But the mind is the agent that programs the brain, that decides what engrams [an engram is a memory trace] shall be encoded in the computer for future retrieval.

Brain Does Not Account for Mind

     As Penfield pointed out, and as the monist would expect, if man's being consists of only one fundamental element, then brain neuronal action must account for everything that the mind does.
(68) But in that case is there not some evidence of specific neuronal activity corresponding to the thinking that the individual is doing? To this Penfield answers no. Such evidence had

67.Penfield, Wilder, The Mystery of the Mind, Princeton University Press, 1975, p.80.
68. Ibid., p.78.

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not been found in any of his patients. Yet he is careful to admit that there may be such neuronal activity not yet demonstrated. Moreover, he has observed that substantial areas of the cerebral cortex can be removed without any loss of consciousness by the subject even during the operation, a fact which suggests that consciousness is not specifically localized.
     He summed up his conclusions by emphasizing that his own surgical experience never revealed any area of matter in which local epileptic discharge resulted that might be described as mind-action.*
      Since there is no evidence for such action, Penfield concluded that the only explanation must be that there is indeed another basic element and another form of energy, that as a programmer acts independently of his computer, even if he depends on the computer's action for certain things, so the mind seemingly can act independently of the brain. (70)
     If the dualistic view is never explored, we shall never design experimental tools to uncover the mechanism of interaction between the two elements. It before seems logical to allow dualism as a working hypothesis and to see whether new avenues of approach to the problem may not be invented in the more open climate that such an allowance would generate. Penfield was convinced we must broaden our hypothetical base.
     In this spirit he then turns to a consideration of some more subtle and perhaps more fundamentally important questions that the evidence invites us to ask. He

*The question of whether there is an actual memory trace in the form of RNA specifically relating to each memory is still an open one. The experimental evidence that planaria which have learned some avoidance action have a particular RNA which, when fed to untaught planaria, gives them a head start in the learning is still a matter of debate. See for further reading: Arlene L. Harty, Patricia Keith-Lee, and W. D. Morton, "Planaria: Memory Transfer Through Cannibalism Reexamined," Science, vol.146, 1964, p.75; Allan L. Jacobson et al., "Planarians and Memory," Nature, vol.209, 1966, p.599—601; G. Ungar and L. N. Irwin, "Transfer of Acquired Information by Brain Extracts," Nature, vol.214, 1967, p.435—55; Ejnar J. Fjerdingstad, Chemical Transfer of Learned Information, New York, Elsevier, 1971; R. M. Yaremiko and W. A. Hillix, "Reexamination of the Biochemical Transfer of Relational Learning," Science, vol.179, 1973, p.305.
69. Ibid., pp.77—78.
70. Ibid., pp.79—80.

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points out that the history of the mind's development during life as opposed to the brain's course of development is rather different. (71) For example, if one plots a curve showing the excellence of human performance, one sees that the body's performance (and the brain's) improves with time as maturing takes place, until after a certain stage in life when a decline begins to set in and ultimately senility. By contrast, the mind reveals no characteristic or inevitable decline. In fact, in old age it reaches toward its fullest potential of understanding and judgment, while the body and the brain are slowing and sometimes failing to perform. (72)
     He makes a final observation that he had worked as a scientist trying to prove that the mind was accounted for by the brain and, demonstrating as many brain mechanisms as possible, he hoped to show how it was thus explained. He ends his reflections by saying:

     In the end I conclude that there is no good evidence, in spite of new methods, such as the employment of stimulating electrodes, the study of conscious patients, and the analysis of epileptic attacks, that the brain alone can carry out the work that the mind does. I conclude that it is easier to rationalize man's being on the basis of two elements than on the basis of one.

     Such, then, is the much examined and carefully stated opinion of a man who has had perhaps more first hand experimental knowledge of the data than any other person at the present time.

71. Ibid., p.86.
72. Ibid., p.87.
73. Ibid., p.113.

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Copyright © 1988 Evelyn White. All rights reserved

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