Popular Science Monthly/Volume 46/April 1895/Some Curiosities of Thinking
THE
POPULAR SCIENCE
MONTHLY.
APRIL, 1895.
SOME CURIOSITIES OF THINKING.[1] |
By M. ALLEN STARR, M. D.,
PROFESSOR OF DISEASES OF THE MIND AND NERVOUS SYSTEM, COLLEGE OF PHYSICIANS AND SURGEONS, COLUMBIA COLLEGE.
IT is evident to any one who has kept abreast with the recent progress in psychology that the advance in the knowledge of mental processes has been greatly aided of late by contributions from certain collateral branches of science. The older method of introspection had, indeed, resulted in establishing many facts and in formulating numerous laws of psychical action. But this method had many defects, and it must be admitted by any candid observer that the debt which psychology owes to more modern methods of research is a deep and lasting one. To these methods also we owe much of our present knowledge of what may be termed the mechanism of thinking.
It may not be without interest, therefore, to review some of the results which modern studies have reached, especially as such a review will bring before us some entertaining curiosities of thinking.
And, first, we must mention the remarkable discoveries in regard to the localization of brain functions which may be traced to physiological experimentation upon the lower animals. It was long ago determined by Fritsch and Hitzig, Ferrier, Munk, and Beevor and Horsley that in the lower animals certain districts upon the surface of the brain could be laid down, to each of which a definite sensory or motor function could be assigned. Within the past decade it has been absolutely proved by pathologists, among whom Charcot, Nothnagel, and Ferrier must be named, that the same statement may be made with regard to the brain of man. To-day a practical application is being constantly made in our hospitals of these important discoveries. For they not only enable us to determine the position of disease in the brain, but also afford a guide to the surgeon, who can cut through an apparently healthy head and skull and remove the diseased tissue. The results of brain surgery form one of the triumphs of medical science of which physiologists may justly take the credit. It is now well determined that from the eye, or from the ear, or from the skin definite nerve tracts can be traced to special regions of the brain. It is well known that all impressions received by the eye, or ear, or skin set up impulses which traverse these tracts and reach these special areas of the brain surface or cortex. When an impulse reaches the cortex a conscious perception is produced, and of this perception a definite memory remains, which memory is necessarily connected with the brain cells in the special area primarily excited. If disease destroys a sensory area, perceptions are no longer possible in the sensory organ to which it belongs, and memories stored up in that area are permanently lost. From this loss of particular perceptive power and of memories it is possible to determine the position of disease in the brain so exactly that it has been found feasible and justifiable to proceed to the removal of the disease, such as a clot or tumor, producing the symptoms.
It would afford material for an entire paper to study defects of memory and to describe some of the curiosities of thinking which result from such defects. A few examples may be related.
I saw lately a business man of keen mind and good general memory, who was not paralyzed in any way, and was perfectly able to understand and to talk, but who had suddenly lost a part of his power of reading and of mathematical calculation. The letters d, g, q, x, and y, though seen perfectly, were no longer recognized, and conveyed no more idea to him than Chinese characacters would to us. He had great difficulty in reading—had to spell out all words, and could not read words containing three letters. He could write the letters which he could read, but could not write the five letters mentioned. He could read and write some numbers, but G, 7, and 8 had been lost to him; and when asked to write them his only result, after many attempts, was to begin to write the word six, seven, or eight, not being able to finish these, as the first and last contained letters (x and g) which he did not know. He could not add 7 and 5 together, or any two numbers of which 6, 7, or 8 formed a part, for he could not call them to his mind. Other numbers he knew well. He could no longer tell time by the watch. For a week after the onset of the disease he did not recognize his surroundings. On going out for the first time the streets of the city no longer seemed familiar; on coming back he did not know his own house. After a few weeks, however, all his memories had returned excepting those of the letters and figures named; but as the loss of these put a stop to his reading and to all his business life, the small defect of memory was for him a serious thing. Experience has shown that such a defect is due to a small area of disease in one part of the brain. Such cases are not uncommon, and illustrate the separateness of our various memories and their dependence upon a sound brain.
Among the curiosities of thought which the physician meets with, unexpected perceptions suddenly appearing before the mind with the same vividness as ordinary perceptions, but without any accompanying external excitant, are not uncommon. A person may look at an empty chair and yet see a familiar form seated in that chair, and may even hear remarks made by this imaginary figure and not doubt for a moment that the figure is an actual entity.
I have seen persons talking with such imaginary individuals, and have had them assure me that they were as sure of their presence and of their voices as they were of my own. I have seen persons manifest the greatest alarm at the presence of animals about them, and refuse to believe from assurance that those animals were not there.
A young woman, having once been frightened by the sudden presentation to her of a white mouse, has been troubled for years by seeing this mouse running about her, upon her clothing, upon anything she is handling, and even upon her food; and, as a result, she is in a state of constant agitation and perplexity, though at times convinced that this is the product of her mind. She washes her hands and her clothing frequently because she is convinced that this animal has made them dirty; and she can not divest herself of the belief that it is real.
I have sometimes been able to convince persons that such fancied figures were not real by asking them to push one eyeball up a little with the finger. This makes all objects about them seem double, as any one can prove to himself, but it does not double the false image—the product of the mind. The young woman just mentioned was much comforted by this device.
Argument alone does not suffice in such a condition to convince one that an impression is erroneous. Thus, a woman who had gradually become totally blind, and was willing to admit that she could see nothing whatever, could not be convinced that she was not surrounded constantly by multitudes of little gnomelike pygmies, whom, she persistently declared, she saw before her, and whom she was afraid that she would step upon or crush by any movement of her body. Yet she was blind. And when these false perceptions occur in the domain of hearing, either taking the form of definite commands, such as "You shall not eat" "You can not move," "You are a lost soul" or such a terrible order as "You must cut your throat," the impression which is produced may be so intense as to dominate the mind and hamper all mental action; and if these commands are not recognized as products of internal disease, they may lead to actions, such as suicide or homicide, which a sound judgment would condemn.
Our knowledge of the localization of brain functions, so far as sensory impressions are concerned, has enabled us to explain not only defects of perception and of memory, but also these false perceptions which we term hallucinations. It has made it evident that such hallucinations are the result of irritative disease in the definite region of the surface of the brain in which the memory pictures were stored. Disease excites the cortical cell to activity. The mental result is a perception which consciousness has no means of distinguishing from an actual perception, and which in a diseased state it regards as real.
The localization of motor functions is no less precise than that of the sensory functions. Every movement of a voluntary character, from the coarse act of grasping an object to the fine touch of the pianist, or the delicate stroke of the artist, or the graceful balancing and light movements of the dancer, originates in a well-defined portion of the brain surface. Destroy this portion of the surface and no amount of volition will produce the desired act; or let this portion be irritated by disease and, without the will, the act will be performed over and over again in an automatic manner and apparently without purpose.
The mechanism of speech has also been determined by these investigations into the localization of brain functions. We know that the understanding of words when spoken or when seen in print, and the articulation of words in speech or their production in writing, are all dependent upon the integrity of definite regions upon the brain surface. So positive are we of this that in certain cases, when either the comprehension of language is suddenly suspended by disease or the power of utterance of language is hampered by disease, we can put our finger upon the spot in the brain which is affected; and if that spot is pressed upon by a clot of blood or by a new growth, we can remove it and thus restore the power of understanding speech or the power of utterance. Dr. McBurney has reported[2] the case of a physician whose speech was thus restored after three months of silence by the removal of a clot from the motor speech center.
It is thus evident that research in experimental physiology has had an extent and an application to human psychology which were hardly dreamed of by the original investigators twenty years ago; and it is clear that as, little by little, the facts to which I have just alluded have been established, they have been seen to throw much light upon psychological processes, and to make our knowledge of the mechanism of thinking both wider and more precise.
Secondly: There is another field of investigation from which rich results for mental science have recently been reaped—namely, physiological psychology. The determination of the special function of different parts of the brain, and the fact ascertained by anatomists that each of these parts is related to other parts by means of great bundles of nerve fibers which pass throughout the brain in many directions, joining the different functional areas with one another, have led to the study of the association processes which lie at the basis of most of our thinking.
Mental images never occur singly, but are usually in close relation with other images, the result of simultaneous perceptions. The various qualities of an object perceived by different senses are united in our concept of the object. The beautiful form of the rose, its charming color, its delicate odor, the soft, velvety feel of its petals, and the sharp prick of its thorns all come into my consciousness through various channels, but, being simultaneous in their perception, are all joined with one another in a complex unit—the concept; and when I call to mind a rose, it is not one memory of a single sensation which comes into my consciousness, but it is the associated memory pictures of sight and smell and touch which, by a flash of consciousness, rise together into the mind. And since it is possible to analyze these sensations, it is also possible to trace the association between them. I do not hesitate to call to mind the appearance of the rose, even though I merely perceive its delicate perfume, and there is hardly a flower whose name is not brought up the moment I see or smell it. Yet this process of calling up the image of the flower from its odor, or of calling up its name when I see it, involves a process of transmission of physical impulses from one region of the brain to another—a process of which the physiological psychologist has actually determined the time. We measure associations in hundredths of a second, and with decided accuracy. The mental act of ordinary single association may be said to occupy an eighth of a second The time of the transmission of these impulses varies decidedly at different periods of life, though it requires no delicate apparatus to convince one of the contrast between the quick, acute association of the young man and the slow, uncertain, halting memory of the aged. It has been found by Kroepelin that the rapidity of the association processes can be altered by the use of certain drugs. Thus alcoholic beverages make the sensory perceptions and the process of thought slower than normal. They increase the rapidity of motor acts for a short time, but finally retard these, too. Tea has just the opposite effect, making sensations and intellectual acts more rapid, while it delays the motor actions. Morphine has at first much the same effect as tea, but soon after it delays all mental acts.
I have noticed that one of the early signs of beginning disease in the brain is a decided lengthening in the processes of association, even where none of these processes are absolutely suspended.
The number of associations permanently established with any given idea has been made the subject of tests, and it has been said that it is a better measure of the mental capacity of an individual to ascertain the number of associations which he possesses with any given subject than to require him to pass an examination upon his knowledge of the subject.
Among the curiosities of thought we may mention some queer disturbances in these processes of association. We may find that association tracts are apparently blocked so that a perception which should call up a certain concept fails to do so.
I have seen a man look at his own son and yet fail to recognize him—that is, the perception of the face no longer resulted in the quick spreading outward over a thousand associated tracts to other parts of the brain of impulses calculated to call up the numerous memory pictures usually associated with that face. Not long ago I asked a man who had one of these forms of defective association what his occupation was. He replied: "What I do? My business? I know just as well as I know all of it, but I can't tell," The idea of his occupation was unable to carry him on to its name. He was a printer. He assured me that he could call to mind his office with its presses and frames, but he could not name his occupation; yet he recognized the word printer at once when I spoke it, and knew it was what he wanted to say. One process of association, at least, in his brain was suspended.
Some of the extraordinary disturbances of consciousness in which an individual's personality appears to be divided, instances of which I shall give later, seem to be explicable only on the theory of the cessation of activity of the association fibers of the entire brain for a time.
I may mention here an unexpected association, a sort of spontaneous association between unrelated perceptions, which is observed in some minds. You may have heard that there is such a thing as color-hearing—i. e., persons subject to this forced association find that certain colors awaken forcibly the memory of certain sounds, which memory may be so vivid as to be a hallucination. A color may cause a shrill sound to be heard. I was told lately of a lady who was overcome by such a sound on entering a room where decorations, hangings, and furniture were red in color. On the other hand, certain sounds may awaken the idea of colors. I have heard of a man who seemed to see the color green when he heard a violin played; another person always had a sensation of red at the sound of a trumpet. Another person,[3] who had become blind, had retained this persistent association, and when the vowel sounds were pronounced slowly he had, accompanying each, a sensation of color like a transparent colored sheet a short distance in front of his face. Each vowel sound had its own corresponding tint, which was always the same for that vowel: a was red; e, gray; i, black; o, white; u, green. When the vowel sounds were uttered in rapid succession there appeared to be a confused, rapidly changing faint screen of color, but it did not obtrude itself on his consciousness unless he expressly directed his attention to it. This association persisted after this man had become blind. Many such instances have been recently collected by Flournay in his interesting book, Des Phénomènes de Synopsie. It is said that twelve per cent of people have such a power of color-hearing. It is certainly a fact that the most of us have an unpleasant involuntary feeling on hearing certain sounds. We all dislike the creaking noise of a slate pencil drawn across the slate or the sound produced by a man filing a saw, I think this is more than mere dislike of sound—it is a real sensation of a non-auditory and painful character a forced, unnatural association.
Thirdly: The study of child life and of the mental development of the infant is the third line of research which has been of great service in the investigation of mental action. It is not possible for one accustomed to think without regarding his mental processes to suddenly stop in the course of thought and analyze accurately his methods of thinking. The rapidity of associations, their determination in certain lines by habit and by use, and their enormous number in the active mind, baffle all analysis. But if we watch the growth of thought in the child, if we notice the accumulation of memory pictures, the gradual building up of concepts and the formation of the links in the chain of reasoning, we can get at the elements of many complicated mental processes Thus the study of the mental growth of the child throws light upon the study of adult thinking.
And here, too, the value must be recognized of the study of those imperfect minds which are arrested in their development at certain points. Thus, there are children whose powers of perception appear to grow with their growth, whose powers of recognition of persons and objects about them are good, but who seem to stop short at the point where these individual perceptions and memories should be grouped together into general ideas. There is an inherent activity in the brain of a child which leads to thought and soon to actions and speech; yet there are children who never get to the point of definite purposeful activity. Such children are usually in constant motion, but their movements have no object. Such children can not be taught to talk, or, if they can be instructed in repeating words after another, they seem to attach little significance to the words that they say, and appear to have no spontaneous wish to talk. Back of any spontaneous desire to speak, there must be the idea which presses for utterance, and thus we conclude from the study of these defective, speechless creatures that while perception may be active, the mind has not grasped the subjects perceived, has not gone on to any generalization about them, or initiated a train of thought to issue in action or articulation. Such a child, then, reveals to us the order of progress in mental growth. It has the rudimentary power of simple perception and memory and association of memories; but it lacks the next higher power of thought, the power to group ideas together, to contrast them with each other, to generalize. And since it is this generalizing and analyzing power which stimulates thought and leads to natural curiosity, we find such children fail to give evidence of that desire for knowledge which a healthy child displays.
Another type of child far less defective is not uncommonly seen, who has nevertheless failed to reach that point of development which is evidenced by the power of self-control. These children may have the power to recognize objects, to analyze their qualities, to reason upon them, and to accumulate a little store of knowledge. They can talk, and learn to do many acts of a complex nature and of delicate manipulation. But the power of concentration of the mind upon a definite subject, the power of paying strict attention to one thing to the exclusion of all recognition of the thousand impressions which ordinarily press in upon consciousness and which the attentive mind ignores, this power they seem to lack, and hence, because of this defect in the attentive faculty, or of the power of controlling and directing mental action, these children are incapable of giving any stable direction to their life and conduct. I have a young man under my observation who is capable and active mentally in many directions, has apparently no gross intellectual defects, yet who complains that he is utterly unable to direct his mind continuously to any topic. He is a college graduate, but for the past ten years he has drifted about from one occupation or profession to another—eager for a time in each, then losing all interest, finding himself unable to fix his attention any longer on his work, lapsing into a state of apathy and mental inertia, disappointed at himself and at his failure of interest, but incapable of arousing himself to effort. This is not laziness—it is an inherent mental defect.
Again, there is a type of mind which seems deficient only in the perception of the true relation between events and actions. These people are the victims of their fancies. They are constantly originating most impracticable undertakings. They expend their energy in devising and attempting to carry out the most useless, absurd, and extravagant schemes—sometimes selfish, sometimes apparently philanthropic. They appear to ignore or else can not appreciate the force of common-sense objections, or the reality of insuperable obstacles to their projects; and, finally, if they are defeated, they never blame themselves, but either complain of the lack of human sympathy, or become the victims of a delusion that they are the objects of a conspiracy by enemies whose existence is purely imaginary. The patent office contains a striking museum of such hopeless and visionary schemes and inventions.
It is impossible in the study of defective minds to draw any sharp lines between different individuals; and we can not help feeling that between the man of giant intellect on the one hand, and the speechless idiot on the other, there is an unbroken line of descent, and every possible variety of mental defect.
It is in some of these degenerate brains that we find some of the strangest curiosities of thinking, and some of those extraordinary developments in one line of mental capacity with a corresponding suppression of all other lines. One has only to think of such an individual as "Blind Tom," the pianist, who was a genius in music, able without instruction to reproduce upon the piano with marvelous elaboration of harmony almost anything musical which he had heard, and yet who was almost a brute so far as his moral nature was concerned, and almost an idiot so far as his intellectual powers could be measured. We might also cite a remarkable person recently seen in New York, "Inaudi," who, though until the age of twenty unable to read or write, because too stupid to learn, and manifestly defective in mental capacity, has a power of mathematical calculation which is most extraordinary and inexplicable. The most abstruse problems m arithmetic, such as cubes of numbers in four figures, or a square root of figures in millions, it takes him but a few seconds to solve and this he has been able to do ever since a little boy, without being able at all to explain his methods of doing it. He is as accurate as a calculating machine (and just about as intelligent on other subjects). He relates his history as follows:[4]
"I was born at Onorato, in Piedmont, on October 13, 1867.
"I began life as a shepherd boy, and when about six years old I went with my father into France. There I made a little living by wandering about from café to café dressed in my Savoyard's costume, and exhibiting some white mice which I had taught to perform some tricks.
"My brother taught me the names of the figures and their values, but the symbols which represent them were quite unknown to me. Indeed, it is only within the last five or six years that I have become at all familiar with them.
"As a matter of fact, the sight of figures embarrasses me even yet. It is through the sound, through the name of a figure, that my mind recognizes its value. If I see the sign which stands for it, I have to translate it, as it were, into a name familiar to my ear. Indeed, my eyes play no part at all in my process of calculation. 'Nine' conveys a distinct impression; the figure 9 has to be translated into 'nine' before I can do anything with it.
"The instant the names of the figures strike my ears the process of calculation begins. As one thing after another is disposed of, I place it on one side ready for reference in getting at the final result—not by mental vision, but by mental audition. I never, in thinking about numbers, see the figures; I hear them.
"My processes of calculation I had to invent. You see, I never learned arithmetic. When I had been taught the names of the figures by my brother my education came to an end. Instinctively I began to perform certain simple calculations. And, like all uneducated persons, I always calculate from left to right, instead of from right to left, beginning with the highest value instead of with the unit."
He himself, although perfectly conscious of the process through which his faculties work out the desired result, can not explain how he can arrive at that result so quickly. "It is there," he said, touching his head, "but the answer comes mechanically, without effort, without research, mechanically even."
"After a difficult calculation, do you experience any fatigue, M. Inaudi?" he was asked.
"Not the least in the world. I am quite unconscious of anything that is going on. Even the methods by which I arrive at the required result are so mechanically employed that it is simply like reading a newspaper." This indifference is proved by the fact that no interruption deranges M. Inaudi. He will listen and join in the conversation while continuing his unraveling of the problem. As an example of the rapidity of his power of calculation, it may be mentioned that it took him but twenty-three seconds to reckon the square of 5,892.
"When I take a pencil I work much slower than you would, and am not at all reliable. When I make a calculation mentally, the least error seems to strike my organ of hearing. I feel, if I can so express myself, the inaccuracy. When, on the other hand, I work with pen and paper, I might make several errors and should not discover them until I made the proof mentally."
This was naturally to be expected from one who frankly avowed that until a few years ago he was perfectly illiterate.
"I have no memory, however, for other things except figures," said M. Inaudi. "Nothing else seems to make any impression upon me. If I read anything, I forget it almost immediately. If anything is told to me, the result is the same. Few things interest me save numbers. In fact, I have no aptitude for anything else."
It is evident that Inaudi has a mind developed largely in one direction, but undeveloped in others.
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The more the processes of thought in such minds are analyzed and contrasted with those in normal minds, the more apparent it becomes that each individual has his preference m mental imagery, and that in each person the mind habitually works more actively through one sense than through the others. This distinction was most acutely drawn by Charcot, who classified people into "visualists"—those whose recollections were chiefly of things seen, who had to read a name in order to remember it; "audists"—those whose memories were of things heard, whose auditory sense was paramount; and "motors"—whose powers were greatest in acts of expression, whose memory depended upon writing a thing down, whose talents lay in action. One can easily determine to which class one belongs by ascertaining in any act of memory whether he sees or hears or feels the thing remembered most easily, and by watching one's habitual references to memory. It may be remarked that such a discussion as that concerning universals in logic, in which the logicians ranged themselves in the rival camps of nominalists, realists, and conceptualists, probably had its origin in the various methods of habitual thinking in different minds. And in view of the facts of localization already described, it may be asserted that these inherent differences of thinking depend on various degrees of development of various districts of the brain cortex, or of the association fibers in these districts.[6]
Fourthly: From this type of mental development—presenting an excess in one direction, with or without defects in other directions we will pass to another type of defective mind which has of late been most carefully studied, especially by M. Magnin, of Paris, the foremost French alienist.
There are certain persons in the community, usually the children of nervous or alcoholic parents, who present mental peculiarities which force upon us the conviction that there is a lack of equilibrium in their mental acts. They are not defective in faculties of sensation, memory, reasoning power, or action. They are often persons of brilliant qualities in certain directions, and perhaps have attained distinction in art or in the professions. But they may be the victims of sudden, unreasoning impulses, desires, doubts, or fears, which so dominate for the time their thought and acts as to lead one to the conclusion that their minds are not well balanced, though it can not be said that they are insane.
Let me give some examples from my own experience. A nervous woman began to notice her breathing, and for three months was beset with the fear that it would cease to continue if she did not watch it. She moved one of her fingers synchronously with her respiration; or else rocked in a chair, keeping time with the act of breathing. It was impossible to take her mind off of it. If she talked of something else, she was thinking of it all the time and watched it. If she tried to stop thinking, she became anxious and distressed and had to continue. Finally, this condition passed away as suddenly as it came.
This, then, is an example of a fear relating to a simple physiological act, which calls the attention to the act, and gives rise to great distress of mind, I have seen persons who were unable to talk or to move a hand, or to walk, because of such a fear that they could not move; the fear appearing to suspend the power of volition. When the fear was quieted, and assurance regained, the power returned. In other cases, an imperative desire to do some absurd or useless thing seems to take possession of the mind. Thus, a little girl of delicate nervous organization, and who had been studying rather too earnestly in school, was suddenly seized with the impulse to count everything. If she enters a room she counts the chairs, the objects on a table, the bric-a-brac, or the pattern in a carpet. If she begins to talk, she has to count the words she says, or the words spoken by any one else, so that she is obliged to talk slowly, and is often so occupied in counting that she forgets what she is going to say before it is done. If she is made to stop, she feels great distress and a sense of anxiety which is painful.
Such fears may extend to higher mental acts involving volition.
One of the postmen whose duty it is to collect letters from the corner boxes in New York was recently discharged because he was always behind time on his rounds. He was much distressed at this, and finally revealed the reason: As he went about he would empty a box and lock it, but after going a few steps he would be seized with a fear that he had not locked the box, so he would go back and feel of it and assure himself that it was locked, and then start on again, but only to be again seized with this fear, which led to the impulse to return and try the box again. Thus, he would often return three or four times to each box emptied, and, of course, the delay made him so late on his rounds that he lost his place. He could not control the fear, or reason against it. The anxiety overcame him each time, and it was impossible to avoid the return.
A middle-aged lady, of much intellectual force and a keen power of analysis, had suffered from distressing mental tendencies ever since a child. These became very intense about her fortieth year, and remained for five years. She is abnormally conscientious—constantly imagines things which she ought to have done, and reproaches herself with not having done; or thinks of things which are wrong which she might do, and then reproaches herself for the thought. She once thought that she might thrust a needle into the eye of a person whom she loved; she then reproached herself for this idea, felt that she had done this person a wrong, felt that she must make amends in some way, confessed her idea to the person, and was met by natural remonstrances which increased her distress. She lives with some relatives, and has a frequent impulse to go behind them and push them downstairs. She has never done so, but reproaches herself for the idea. If she sees a rug on the floor lying crooked, the idea comes to her that one of these relatives may stumble on it, and this for the moment gratifies her; then she reproaches herself for the thought, goes and fixes the rug; is not satisfied with the way she has fixed it; wonders if she could have placed it so that it could trip up this relative; fixes it again, over and over, sometimes twenty or thirty times, and can not get rid of the idea that after fixing it she would be guilty if her relative slipped upon it. The doubts extend to other things. She will turn out the gas on going to bed, then has to go back and feel of the fixture to be sure that it is turned out, and often repeats this twenty times before she can get rid of the idea that it is really turned on. In her room she has to arrange everything in a very precise manner, and often spends hours placing and replacing objects before she can satisfy herself that they are right. It is impossible for her to argue with herself regarding these matters, and if she resists the tendency to repeat an act she gets into a state of distress, with palpitation of the heart and every evidence of intense anxiety, which nothing will quiet except the repetition of the act.
A lady aged twenty-nine had mental symptoms since the age of eighteen, when great timidity in driving began. She gets nervous at any excitement. She is subject to morbid fears; sees a match-box, wonders if the matches are safe—might they get out, and be lighted and set things on fire?—hence, goes to the matchbox, and makes sure it is shut; then goes back again, and so may repeat this twenty times. She can not reason with herself. Or, she wonders if the windows are shut; has to go and put her hand on the window to be sure, and this she does again and again. If she has medicine, she fears it will get out of the bottle; she goes and feels to see if the bottle is corked. She has the constant fear that things are not right, and has to reassure herself. Has to say things in a special way, and over and over, so it is hard for her to talk, and she repeats words. In reading she notices each word and can not read fast, but must read exactly; hence, she takes no pleasure in reading. Her condition makes her restless and melancholy. She is perfectly sane, but she is the victim of a morbid tendency to doubt the certainty of any idea which presents itself to the mind.
In all these cases the act which is done, and which is apparently absurd, is the outcome of a process of reasoning starting from a premise, which premise is an absurd fear or doubt. There is nothing wrong in the act or in the process of logical conclusion, granting the premise. The premise is, however, a false idea forced upon the consciousness so intensely as to carry conviction. It is quite analogous to a hallucination in the domain of sensory perception, but it belongs to the ideational sphere, or to the emotional sphere of mind. You will have noticed that the same sort of doubts occur to different minds.
It may be said that such fears, doubts, or impulses might occur to any one, but could be at once discarded. In the fact that they are not discarded, that there is a lack of self-control and mental balance which allows of their taking possession of the mind, lies the proof that in such cases there is a defect of mental development. Such cases show us clearly how important it is to sound normal mental action that a firm control over the tendencies of the mind to wander foolishly, to indulge in absurd doubts and fears, should be constantly exercised; and such control should be inculcated upon the child's mind as it develops, lest the individual come to yield to or to foolishly fear these abnormal impulses. That self-control is the highest quality of mind is evident from the fact that the first evidence of mental deterioration is seen in a beginning failure of this power.
You are all familiar with the fact that many acts of an insane kind are spontaneous, and not the result of a process of logical reasoning. Thus, a sudden impulse to steal, or to set fire to an object, may come upon one and lead to the act, for which no explanation can be given except the sudden onset of an abnormal and irresistible desire. These acts are in a way as unexpected as the hallucinations or the doubts or fears, and like them must be ascribed to sudden excitation of brain functions beyond our control from internal causes, the effects of disease. Such acts are not of much interest to the student of psychology, for they do not involve a process of thought. They are most commonly observed, however, in persons of the degenerate type which we have been studying. In these persons, then, of degenerate type we observe an imperfect mental equilibrium, which prevents a successful resistance of sudden impulses, and a successful suppression of sudden doubts and fears, and which thus deprives the victim of his liberty of action in spite of his conscious knowledge that the impulses or doubts are absurd or wrong. From time to time in their lives these persons suffer for weeks and months from their mental distress; then, for unknown reasons, they may be free from it, but usually it returns, and it is an annoyance through the entire life. One of the most interesting studies of the mental processes of a person thus afflicted has been published by Prof. Royce, of Harvard, in the American Psychological Review—the case of John Bunyan.
Lastly, there is one other curiosity of thinking which as yet remains unexplained, but which at present is exciting a considerable degree of interest. I refer to the condition known as double consciousness. Let me give an illustration.
A young man, a carpenter by trade, of fair intelligence and good physique, had a severe fall upon the head in January, 1879, and subsequently to that time suffered from occasional attacks of unconsciousness with convulsions, which were thought to be epileptic. He was treated from July, 1884, until January 10, 1885, for this disease, and during that time had no attacks. On January 10th he came home from work as usual, ate his supper, and went to bed. He slept with his brother, who is sure that during the night he had no convulsion. The patient says that when he woke up on the 11th of January he found himself in Bellevue Hospital, and learned to his surprise that it was evening. He has no recollection of anything which occurred beween going to bed on Friday night and waking in the hospital on Saturday night. From his family, however, it was ascertained that he got up as usual on Saturday morning, and while it was noticed that he acted a little strangely at breakfast nothing was said to him, and he went as usual to work. His employer thought that his eyes looked brighter (possibly his pupils were dilated) and that he did not appear natural, but he took no special notice of this, and soon after his arrival at the shop in Twenty-fourth Street he sent him up to a house in Forty-sixth Street (about a mile) on an errand, to obtain a carpenter's bit and brace. He went up to Forty-sixth Street, did the errand, and evidently explained himself intelligently, for he was given the bit and brace. The next trace he has of his movements was at Eighth Avenue, near Bleecker Street (about two miles away), though how he got there he does not know. He there went into a plumber's shop, and asked to be allowed to sit down and rest. He had nothing in his hands, so must have lost the bit and brace on the way. He soon got into a lively talk with the plumber, and became quarrelsome, so that he was told to go out. He went away, but in an hour came back, entered the shop, and tried to strike the plumber. This was for him an unusual proceeding, as he is of a mild and gentle disposition. An officer was summoned, who took him to the police station, where it was evident that he was out of his head; so they sent him to St. Vincent's Hospital, whence he was at once transferred to Bellevue. He fell asleep soon after admission to Bellevue, and on waking in an hour or so was surprised to find where he was. His manner of talking made it evident that nothing was the matter with him, and he was discharged at once and went home, rather indignant at having been sent to a hospital, and anxious to find out the reason. Being a very intelligent lad, ho became interested in his own case at once, on learning a few of the facts, and ascertained by inquiry the various occurrences which have just been described. Soon after this I lost track of him, and do not know whether any similar attacks have since occurred.
It would be easy to offer other illustrations of a condition of mind very properly termed double consciousness. It is as if a single individual had two separate and distinct personalities, neither of which has anything in common with the other. All associations, all memories of one condition seem to be blotted out or suspended when the person is in the other condition. It is a remarkable fact that such a state is usually produced by a blow or a fall, and it is a well-recognized complication of railway injuries and of severe accidents that such a state of secondary consciousness may follow for several hours or days, but in the case here related nothing of this kind preceded the onset. And it must be remembered that such a state of secondary consciousness or abnormal personality may also be produced by hypnotic suggestion. Persons who are hypnotized are in a condition quite similar to that described as a state of secondary consciousness—that is, they have no recollection of what has happened before they were put in the hypnotic condition, and after they are awakened they have no recollection of what has happened in the hypnotic condition. Yet in that condition they are able to reply to questions intelligently, and if they are hypnotized a second time their memory of what has occurred on the first occasion is continuous with their memory of what occurs upon the second. Such cases have been described with much care by Paul Janet.
The same phenomena are observed in a less degree in somnambulists, for what a sleep-walker may do one night he may undo on a second night, though having absolutely no recollection of either occurrence in his waking hours.
There is no satisfactory explanation as yet found for these extraordinary alterations of consciousness and personality, and there is much opportunity for study and research in regard to these peculiar conditions. They remain among the curiosities of thinking, inexplicable yet interesting.
- ↑ Read before the Philosophical Club of Princeton.
- ↑ Brain, 1891, p. 284.
- ↑ Lancet, March 31, 1894.
- ↑ New York Herald, March 25, 1894.
- ↑ Revue Philosophique, March, 1894.
- ↑ The examination of Laura Bridgman's brain supports this assertion. For this woman, who was unable to see or to hear, but whose means of communication with the external world was entirely by touch and by motion, had a brain whose visual and auditory regions were undeveloped, but whose sensori-motor region far exceeded in size that of a normal brain.