Part 8

The problem of memory is closely connected with the question of the mechanical relation between thought and structure. How intimate is the alliance of memory with the material condition of the brain, is shown by the effect of age, of disease, of a blow, of intoxication. I have known an aged person repeat the same question five, six, or seven times during the same brief visit. Everybody knows the archbishop's flavour of apoplexy in the memory as in the other mental powers. I was once asked to see a woman who had just been injured in the street. On coming to herself, "Where am I? What has happened?" she asked. "Knocked down by a horse ma'am; stunned a little: that is all." A pause, "while one with moderate haste might count a hundred," and then again, "Where am I? What has happened?"--"Knocked down by a horse, ma'am; stunned a little: that is all." Another pause, and the same question again; and so on during the whole time I was by her. The same tendency to repeat a question indefinitely has been observed in returning members of those worshipping assemblies whose favourite hymn is "We Won't Go Home Till Morning."

Is memory, then, a material record? Is the brain, like the rocks of the Sinaitic Valley, written all over with inscriptions left by the long caravans of thought, as they have passed year after year through its mysterious recesses?

When we see a distant railway-train sliding by us in the same line, day after day, we infer the existence of a track which guides it. So, when some dear old friend begins that story we remember so well; switching off at the accustomed point of digression; coming to a dead stop at the puzzling question of chronology; off the track on the matter of its being first or second cousin of somebody's aunt; set on it again by the patient, listening wife, who knows it all as she knows her well-worn wedding-ring--how can we doubt that there is a track laid down for the story in some permanent disposition of the thinking-marrow?

I need not say that no microscope can find the tablet inscribed with the names of early loves, the stains left by tears of sorrow or contrition, the rent where the thunderbolt of passion has fallen, or any legible token that such experiences have formed a part of the life of the mortal, the vacant temple of whose thought it is exploring. It is only as an inference, aided by illustration which I will presently offer, that I suggest the possible existence, in the very substance of the brain-tissue, of those inscriptions which Shakespeare must have thought of when he wrote--

Pluck from the memory a rooted sorrow; Raze out the written troubles of the brain.

The objection to the existence of such a material record--that we renew our bodies many scores of times and yet retain our earliest recollections--is entirely met by the fact, that a scar of any kind holds it own nearly through life in spite of all these same changes, as we have not far to look to find instances.

It must be remembered that a billion of the starry brain-cells could be packed in a cubic inch, and that the convolutions contain one hundred and thirty-four cubic inches, according to the estimate already given. My illustration is derived from microscopic photography. I have a glass slide on which there is a minute photographic picture, which is exactly covered when the head of a small pin is laid upon it. In that little speck are clearly to be seen, by a proper magnifying power, the following objects: the Declaration of Independence, with easily recognized facsimile autographs of all the signers; the arms of all the original thirteen States; the Capitol at Washington; and very good portraits of all the Presidents of the United States, from Washington to Mr. James K. Polk. These objects are all distinguishable as a group with a power of fifty diameters: with a power of three hundred any one of them becomes a sizable picture. You may see, if you will, the majesty of Washington on his noble features, or the will of Jackson in those hard lines of the long face crowned with that bristling head of hair in a perpetual state of electrical divergence and centrifugal self-assertion. Remember that each of these faces is the record of a life.

Now recollect that there was an interval between the exposure of the negative in the camera and its development by pouring a wash over it, when all these pictured objects existed potentially, but absolutely invisible and incapable of recognition, in a speck of collodion-film, which a pin's head would cover; and then think what Alexandrian libraries, what Congressional document loads of positively intelligible characters--such as one look of the recording angel would bring out; many of which we can ourselves develop at will, or which come before our eyes unbidden, like "Mene, Mene, Tekel, Upharsin"--might be held in those convolutions of the brain which wrap the talent entrusted to us, too often as the folded napkin of the slothful servant hid the treasure his master had lent him.

Three facts, so familiar that I need only allude to them, show how much more is recorded in the memory than we may ever take cognizance of. The first is the conviction of having been in the same precise circumstances once or many times before. Dr. Wigan says, never but once; but such is not my experience. The second is the panorama of their past lives, said, by people rescued from drowning, to have flashed before them. I had it once myself, accompanied by an ignoble ducking and scrambling self-rescue. The third is the revival of apparently obsolete impressions, of which many strange cases are related in nervous young women and in dying persons, and which the story of the dog Argus in the "Odyssey," and of the parrot so charmingly told by Campbell, would lead us to suppose not of rare occurrence in animals. It is possible, therefore, and I have tried to show that it is not improbable, that memory is a material record; that the brain is scarred and seamed with infinitesimal hieroglyphics, as the features are engraved with the traces of thought and passion. And, if this is so, must not the record, we ask, perish with the organ? Alas! how often do we see it perish _before_ the organ!--the mighty satirist tamed into oblivious imbecility; the great scholar wandering without sense of time or place among his alcoves, taking his books one by one from the shelves and fondly patting them; a child once more among his toys, but a child whose to-morrows come hungry, and not full-handed--come as birds of prey in the place of the sweet singers of morning. We must all become as little children if we live long enough; but how blank an existence the wrinkled infant must carry into the kingdom of heaven, if the Power that gave him memory does not repeat the miracle by restoring it!

FOOTNOTES:

[3] Burns tell us how he composed verses for a given tune: "My way is, I consider the poetic sentiment correspondent to my idea of the musical expression; then choose my theme; begin one stanza. When that is composed, which is generally the most difficult part of the business, I walk out, sit down now and then, look out for objects in Nature that are in unison or harmony with the cogitations of my fancy, and workings of my bosom; humming every now and then the air with the verses I have framed. When I feel my Muse beginning to jade I retire to the solitary fireside of my study, and there commit my effusions to paper; swinging at intervals on the hind-legs of my elbow-chair, by way of calling forth my own critical strictures, as my pen goes on."--"Letters to G. Thomson," No. XXXVII.

MEMORY

HENRY MAUDSLEY, M.D.

[Dr. Maudsley, of London, is an eminent physician and psychologist. His works include "Body and Mind," "Body and Will," "Responsibility in Mental Disease," "Pathology of the Mind," all published by D. Appleton & Co., New York. From the work last mentioned the following is part of the chapter on Memory and Imagination.]

No mental development would be possible without memory, for if a man possessed it not he would be obliged to begin his conscious life afresh with each impression made upon him, and would be incapable of any education. We cannot perhaps better define memory than, following Locke, as the power which the mind has "to revive perceptions which it once had with this additional perception annexed to them, that it has had them before;" in other words, as the power or process by which that which has been once known is, when _re_presented to the mind, known as a previous mental experience, that is, is _re_cognized. When people speak of ideas being laid up in the memory, they of course speak metaphorically; there is no such repository in which ideas are stored up, ready to be brought out when required for use; when an idea which we have once had is excited again, there is simply a reproduction of the same nervous current, with the conscious addition that it is a reproduction--it is the same idea _plus_ the consciousness that it is the same. The question then suggests itself, What is the physical condition of this consciousness? What is the modification of the anatomical substrata of fibres and cells, or of their physiological activity, which is the occasion of this _plus_ element in the reproduced idea? It may be supposed that the first activity did leave behind it, when it subsided, some after-effect, some modification of the nerve element, whereby the nerve circuit was disposed to fall again readily into the same action; such disposition appearing in consciousness as _re_cognition or memory. Memory is, in fact, the conscious phase of this physiological disposition when it becomes active or discharges its functions on the recurrence of the particular mental experience. To assist our conception of what may happen, let us suppose the individual nerve-elements to be endowed with their own consciousness, and let us assume them to be, as I have supposed, modified in a certain way by the first experience; it is hard to conceive that when they fall into the same action on another occasion they should not recognize or remember it; for the second action is a reproduction of the first, with the addition of what it contains from the after-effects of the first. As we have assumed the process to be conscious, this reproduction with its addition would be a memory or remembrance.

Psychology affords us not the least help in this matter, for in describing memory as a faculty of the mind or the conservative faculty it does no more than present us with a name in place of our explanation. But we do get nearer realities when we go down to the organic aptitude which, in consequence of an action, there is to the recurrence of a similar action on another occasion. And physiology presents us with many illustrations of such organized aptitudes. Take, for example, the education of our movements: a designed movement is performed at first slowly and clumsily, and it is only by giving great pains to it and frequently repeating it that we acquire the skill to perform it easily and quickly; the aptitude thereto being at last so completely organized in the proper nervous centres that it may be performed without consciousness on our part, quite automatically. Thus it appears that memory in this case becomes less conscious as it becomes more complete, until, when it has reached its greatest perfection and is performed with the most facility, it is entirely unconscious. After which, if we are psychologists who are content to rest in words and forbear to pursue the facts which they denote, we must cease to speak of it as memory: it has become custom, or habit, or automatism. But if we go beneath words to the property of the motor nerve-centres whereby they react in a definite way to impressions made upon them, organically register their experience, and so acquire by education their special faculties, we perceive that we have not to do in the higher nerve-centres with fundamentally different properties of nerve element, but with different functions which depend upon the same fundamental property. Substitute the highest nerve-centres for the motor nerve-centres, and the complex idea for the complex movement, and what has been said of the latter is strictly true of the former; the idea, like the movement, is accompanied with less consciousness the more completely it is organized, and when it has been completely organized it takes its part automatically in our mental operations, being performed, as a habitual movement is performed, automatically. The physiological condition of memory is, then, the organic process by which nerve-experiences in the different centres are registered; and to recollect is to revive these experiences in the highest centres, the functions of which are attended with consciousness--to stimulate, by external or internal causes, their residua, aptitudes, dispositions, or whatever else we may choose to call them, into functional activity. Stimulated from without, they constitute recognition, that is, cognition with memory of former cognition; stimulated from within, they constitute recollection.

It must be borne in mind, as Dr. Darwin remarked many years ago, that in dealing with memory we have to do not with laws of light, but with laws of life, and that the misleading notion of images or ideas of objects being stored up in the mind has been derived from our experience of the action of light upon the retina. If we would understand the laws of organization in the highest nerve-centres, we shall certainly do well to study organic processes generally; it would be not less absurd to attempt to understand the higher processes without giving attention to the lower, than it would be to attempt to build a house without taking pains to lay its foundations securely. It is a plain matter of observation that other organic elements besides nervous elements perpetuate impressions made upon them, which they may accordingly in a certain sense be said to remember; the virus of smallpox, for example, makes an impression upon all the elements of the body, which they never lose, although it becomes fainter with the lapse of time; in some unknown way it modifies their constitution so that ever afterwards their susceptibilities are changed. The scar which is left after the healing of a wound in a child's finger keeps the same relative proportion to the finger through life, growing as it grows; for the elements of the new tissue not only renew themselves particle by particle, and thus perpetuate it, but they extend it in relation with the growth of the surrounding parts. We need not brave the fire of psychological scorn by calling this retention of impressions _memory_, or care greatly what it is called, so long as due heed is given to the fact; but we may be permitted to perceive in it the same physiological process which, in the cortical [outer] layers of the cerebral [brain's] hemispheres, is the condition of memory, and of habit in thought. Moreover, it may be fairly demanded of the psychologists that they be consistent, and that they no longer use the word memory to denote those mental processes which have been so completely organized that they take place without consciousness; if it be wrong, as they profess, to assume or imply an unconscious memory, it must be still more wrong to assume or imply an unconscious consciousness, as they sometimes do.

In any case, the foregoing considerations cannot fail to show how misleading it is to look upon perceptions as mere pictures of nature, and upon the mind as a vast canvas on which they are cunningly painted; the real process is one of organization, and it is rightly conceivable only by the aid of ideas derived from the observation of organic development--namely, the fundamental ideas of Assimilation of the like and Differentiation of the unlike. Nowhere is it more necessary than in the study of memory to apprehend clearly that what we call mind is the function of a mental organization; for thereby we get rid at once of many empty discussions which have been carried on without definite result; as, for example, whether memory is a knowledge of the past, or a knowledge of the present with a belief of the past, and the like. Moreover, this conception of a mental organization is indispensable to the explanation of the manifold varieties of partial or general loss of memory which are produced by injury, disease and decay of brain; for memory is good or bad according to bodily states, is impaired in various ways by disease, decays with the decay of structure in old age, and is extinguished with the extinction of life in the brain.

From of old two kinds of memory have been distinguished, according as the object remembered occurs to the mind spontaneously, or is voluntarily sought for; the former being known as _memory_ proper, the latter as _recollection_. It is certain that we do recognize this difference, which common language attests, between that which is revived without any effort, and that which we endeavour to recover by an effort; and that men differ much, by virtue of natural capacities, both in memory and in power of recollection. No doubt much of the difference in both cases is due to the degree of attention which is given to the subject when it is first presented to the mind, but this will not account satisfactorily for all the difference which is observed; some persons being able to repeat with great ease a row of figures, a number of dates, or several lines of poetry, after reading them over once, while others fail to do so with equal success after reading them over many times. Extraordinary instances have been recorded of this exactness of memory for details reaching back to the earliest periods of life. I have seen an imbecile in the Earlswood Asylum for idiots who can repeat accurately a page or more of any book which he has read years before, even though it was a book which he did not understand in the least; and I once saw an epileptic youth, morally imbecile, who would, shutting his eyes, repeat a leading article in a newspaper word for word, after reading it once. This kind of memory, in which the person seems to read a photographic copy of former impressions with his mind's eye, is not indeed commonly associated with great intellectual power; for what reason I know not, unless it be that the mind to which it belongs is prevented by the very excellence of its power of apprehending and recalling separate facts from rising to that discernment of their higher relations which is involved in reasoning and judgment, and so stays in a function which should be the foundation of its further development; or that, being by some natural defect prevented from rising to the higher sphere of comprehension of relations, it applies all its energies to the apprehension of details. Certainly one runs some risk, by overloading the memory of a child with details, of arresting the development of the mental powers: stereotyping details on the brain, we prevent that further development of it which consists in rising from concrete perception to conception of relations. However, it must be allowed that there have been a few remarkable instances of extraordinary men who have combined a wonderful memory for details with the possession of the highest intellectual powers.

If we now proceed to examine closely the nature of recollection, it will be found that the difference between it and simple memory is not fundamentally so great as appears on the surface. When we voluntarily try hard to remember something which has been forgotten, and succeed in the end, the actual revival is done unconsciously and, as it were, spontaneously; for it is plain that if we were conscious of what we want we should not need to recollect it, inasmuch as it would already be in possession; and it is furthermore plain that a definite act of volition recalling it must imply a consciousness of it, inasmuch as it is impossible to will what we are not conscious of. Arbitrary recollection by an act of will is therefore nonsense. What we really do when we try to recollect is to apply attention to words or ideas which have, in our past experience, accidental or essential relations to, or associations with, the forgotten word or idea, voluntarily to keep these ideas active by making them consciousness and to trust to their power of awakening into activity that which it is desired to recall; indeed, it is notorious that the best way of succeeding is, having held the related ideas energetically in attention for a time, to allow the thoughts to pass to other things, when the lost idea will, after a longer or shorter time--sometimes indeed after days--recur to the mind. The actual process of reproduction is therefore one of simple or spontaneous memory; we prepare the way for it by stimulating into action the related ideas, but we positively interfere with its success if, by continuing to keep them in attention, we do not permit them to do their work spontaneously; the reason of this being that we thereby hinder the propagation of their activity to other nerve-circuits. We shall understand this the better if we realize that consciousness is the _result_ of a certain activity of idea, not driven to it, but drawn by it, and get rid of the metaphysical notion that it is some mysterious power which we direct voluntarily to the idea in order to make it active.