Popular Science Monthly/Volume 7/August 1875/Infirmities of Speech
|INFIRMITIES OF SPEECH.|
WHAT is necessary in order to our communicating ideas by speech? It is necessary, first of all, that ideas call up their appropriate symbols; secondly, that we remember how to say words; and, thirdly, that our organ of speech be entire—by which is meant, the whole of the muscular apparatus which is brought into action when one articulates.
Now, each of these three capabilities is liable to injury from disease. When the first is affected, the patient forgets words, or uses wrong words, in which a connection with the right ones may be more or less traceable. In the second case, an individual may have lost speech entirely, or he may retain a few words. It is no use helping him out: having forgotten how to use words, he cannot repeat them when they are used in his hearing. In the third case, there is paralysis, it may be, of muscles of the mouth, of the tongue, the larynx, etc. This last form we will exclude from consideration here. The two former constitute the disease called aphasia (as at least understood by some writers), and the study of it makes us acquainted with some curious facts connected with the working of that wonderful organism with which we have been endowed.
There are well-authenticated instances of persons who suddenly found that they could not remember they own names. An at St. Petersburg was once in this case, when calling at a house where he was not known by the servants, and he had to apply to his companion for the necessary information. The names of common things are sometimes strangely forgotten. The wife of an eminent jurist who consulted Dr. Trousseau, of Paris, told him that her husband would say to her, "Give me my—my—dear me! my—you know," and he would point to his head. "Your hat?" "Yes, my hat." Sometimes, again, he would ring the bell before going out, and say to the servant, "Give me my—umbrel—umbrel, oh dear!" "Your umbrella?" "Oh, yes! my umbrella." And yet at that very time his conversation was as sensible as ever. He wrote or read of, or discussed, most difficult points of law. A patient will often use a form of circumlocution to express his meaning; thus one man who could not remember scissors would say, "It is what we cut with."
It may be, however, that not only are the right words forgotten, but wrong ones are substituted. The mother-in-law of a medical man (we are told by Dr. Trousseau) labored under a very singular intellectual disorder. Whenever a visitor entered her apartment, she rose with an amiable look, and, pointing to a chair, exclaimed, "Pig, brute, stupid fool!" "Mrs. B——asks you to take a chair," her son-in-law would then put in, giving this interpretation to her strange expressions. In other respects, Mrs. B——'s acts were rational, and her case differed from ordinary aphasia in that she did not seem to grow impatient at what she said, or to understand the meaning of the insulting expressions of which she made use. Crichton mentions the case of an attorney who, when he asked for any thing, constantly used some inappropriate term; instead of asking for a piece of bread, he asked for his boots, and, if these were brought, he knew they did not correspond to the idea of the thing he wanted; therefore, he became angry, yet he would still demand some of his boots or shoes, meaning bread. One gentleman (a patient of Sir Thomas Watson) would say "pamphlet" for "camphor." Another would say "poker" when he meant the "fire;" Dr. Moore, of Dublin, has recorded the case of a gentleman who completely lost the connection between ideas and words. On one occasion the doctor was much puzzled by his patient saying to him, "Clean my boots!" Finding that he was not understood, he became much excited, and cried out vehemently, "Clean my boots by walking on them." At length it was ascertained that the cause of disquietude was the shining of the candle in his face; and that the object of his unintelligible sentences was to have the curtain drawn. When this was done, he appeared gratified. In this case, it will be noticed, the patient formed complete sentences, the power of coordination and articulation was perfect, and the intelligence was apparently unimpaired. But sometimes, where articulation may be retained, what is uttered is perfect jargon. A gentleman in Dublin, after an attack of apoplexy, was thus affected, and in the hotel where he staid he was mistaken for a foreigner. Dr. Osborn, with a view to ascertain the nature of his imperfection of language, asked him to read aloud the following sentence from the by-laws of the College of Physicians: "It shall be in the power of the college to examine or not to examine any licentiate previous to his admission to a fellowship, as they shall think fit." lie read as follows: "An the be what in the temother of the trothotodoo to majorum or that emidrate ein einkrastroi mestraits to ketra totombreida to ra from treido as that kekritest." Several of these syllables are difficult and unusual.
As indicated above, it is necessary to distinguish between the memory of words and the memory of how to say words. Where the latter memory is lost, the disorder is sometimes called atactic aphasia. The patient may retain a few words, and use only these. There was at the Bicêtre Asylum for many years a man who invariably used the monosyllable "Tan" when any question was put to him. (He went by the name of "Tan.") This, with the exception of an oath (S—N—d—D—!), composed his whole vocabulary. His history, long under observation, furnished some useful data with regard to the physiological relations of aphasia; but we cannot here dwell on this. Another instance, mentioned by M. Broca, was that of a man who had only four words besides his name (which he pronounced "Lelo" for "Lelong"); they were, yes, no, three, and always. He used yes and no at proper times, but he made use of the word three in order to express any number, although he knew well that the word did not always convey his meaning; and corrected the mistake which he made in speaking by holding up the proper number of fingers. Whenever yes, no, and three, were not applicable, he used the word always (toujours). M. Broca infers from this man's case 1. That he understood all that was said to him; 2. That he used with judgment the four words of his vocabulary; 3. That he was of sane mind; 4. That he understood written numeration, and at least the values of the first two orders of units; 5. That he had lost the faculty of articulate language alone. It is to this atactic aphasia alone that M. Broca limits the term aphasia. Another example of it may here be given from Dr. Trousseau. A lady came to consult him with her son, aged twenty-five. This young man could articulate two words only, no and mamma. "What is your name?" "Mamma." "What is your age?" "Mamma, no." He yet knew that he did not answer as he ought. He had taught himself to write with his left hand, the right being paralyzed, but had not got beyond signing his own name, "Henri Guénier." "Since you write your name," Dr. Trousseau told him, "say Guénier." He made an effort, and said, "Mamma." "Say Henri." He replied, "No mamma." "Well, write mamma." He wrote Guénier. "Write no." He wrote Guénier. However much he was pressed, nothing more could be got from him.
There are various remarkable phases of this inability to articulate. One man in the Paris asylum would say "Consisi;" and it might be expected that lie could easily say "con-con" or "sisi," but it was only after several days' trying that Dr. Trousseau got him to say the former, and he never could say "sisi" alone. Another aphasic patient, a woman, could say very well, "Bonjour, monsieur;" but could never be got to say "Bonbon."
Aphasic patients are, as a rule, beneath the average of other men, as regards intelligence, and considerably beneath their former selves, when the comparison can be instituted. There is, however, a very rare form of aphasia in which the intellect is unaltered, memory is good, the patient writes easily, and expresses his thoughts correctly in writing as educated deaf-mutes do. The recovery of the art of writing (where it is recovered) is gradual.
The physiology of aphasia is a subject that has been a good deal controverted, but it now appears possible to explain most of the phenomena by the nature of lesions, and by the very constitution of the nervous system. The following representation of the facts (which we take, in the main, from an eminent French observer, M. Charles Richet) will convey some idea of what medical men hold on this subject.
The nervous system (let it first be understood) is formed of a central part, the brain and spinal cord, and of a peripheric part, the nerves. The nerves are simple conductors, while the central part perceives sensations and determines movement. Now, in this central part, the cerebro-spinal, inclosed by the cranium and vertebral column, as in a case, there are two distinct elements; an active element, and a conducting element. The white substance is the conducting: element; the gray substance the active. The gray substance forms a thin column, which is the central part of the spinal cord, and is continued into the brain where it enlarges. The whole of this column is surrounded by white substance; and in the higher types of vertebrates we find added the so-called "cerebral convolutions." Here the white substance of the brain is folded in various directions, and its entire surface is covered with a thin layer of gray substance. To this elementary exposition it need only be added that the gray substance in brain or cord seems to be formed, not by a single cord, but by a series of nuclei, or centres, placed end to end and connected together. These are sometimes called ganglions. It is in the outer gray substance that will, intelligence, instinct, seem to reside. If the upper part of the cerebral hemispheres be cut in a pigeon, the bird loses all activity: it is incapable of moving voluntarily. It is an automaton which flies when thrown into the air, which swallows when a grain is placed in its throat; but which is without consciousness. Its existence is purely vegetative.
If, instead of the superficial part of the brain, it be the gray axis, the spinal cord, that is injured, all the nerves coming out from it are paralyzed; and, so long as the ganglion from which the respiratory nerves come is not affected, life is possible, however numerous the paralyses. Now, it appears that, for each of our functions, respiration, movements of the heart or of the eye, deglutition, etc., there is a special ganglion of the gray substance forming part of the central column, and. charged with the regular coordination of the movements necessary to the accomplishment of this function. Thus, e. g., in order to voluntary swallowing, it is first necessary that the will determine movements of deglutition, then that this order be transmitted to the nervous centre of deglutition, i. e., a small body of gray substance which anatomists have called the olivary body (on account of its form), and which presides over this function.
Between these two centres, however, of which one is producer and the other coördinator, there is a third, the centre of impulsion. The central gray substance, expanding in the brain, forms two large ganglions surrounded entirely by white substance, except at their base, which is connected with the central axis. These two large cerebral ganglions are called respectively the optic layers and the corpora striata. It is they that determine the motor impulsion, that transmit to such and such a ganglionic nerve-centre the order to put itself in motion. Thus the nervous influx arising from will proceeds from the superficial nerve-cells to the ganglionic centres of the brain, then to the ganglionic centres of the signal cord, issuing in regular movement. It is something like the case of an electric telegraph, with stations and intermediate relays.
Now, coming to aphasia, it seems to have been well established (from post-mortem examination) that there is a limited region of the superficial portion of the brain, on which the faculty of articulate language is dependent, and impairment of which gives rise to aphasia as understood by M. Broca. First of all, it is in the left hemisphere (a curious thing in an organ so symmetrical as the brain). Next, it is in the anterior part of this hemisphere; and, lastly, to be more precise, it is the third cerebral convolution. Agreeably with this, it is found that a great number of aphasic patients are paralyzed in the right side of the body. It must be understood that the nerve-fibres cross over from the left hemisphere.
We may regard the anterior convolutions of the left hemisphere as a sort of logopoietic, or word-forming apparatus, where the previously vague idea becomes precise and distinct, taking a word-form and becoming representative. Lordat distinguishes these two forms of intelligence as the interior logos and the exterior logos. It should be remembered that this conception is a pure hypothesis; but it is in accordance with the facts.
But, for a phrase thought by us to come to the ear of another, a second series of apparatus is required. This is the continuous chain going from the periphery of the convolutions to the central gray column. The nervous influx first goes into those two large ganglions of gray substance, the corpora striata and the optic layers. Probably these organs transform the phrase thought into voluntary movement. From the corpora striata the vibration is transmitted along the central axis to the olivary bodies, which are the coördinating apparatus, and which regulate and direct the movement. From the olivary bodies proceed nerves to the lips, the larynx, the tongue, the pharynx, the palate—all the vocal organs concerned in production of language. Pathological facts teach us that these different apparatuses may be destroyed separately, and there is then involved the absolute loss of such and such a function.
Thus in a case recorded by Dr. Winslow, the man had retained the faculty of language; he could write the words and phrases which he thought of; but, when he tried to speak, he only uttered confused sounds. In this instance the olivary bodies were alone affected. The faculty of language remained intact; the vocal apparatus was not injured; but the apparatus of transmission was profoundly altered.
In other cases, again, it is the organ of thought itself that is diseased. There is an affection well known to physicians who study the insane, and which is called general paralysis. This disease begins in the periphery of the convolutions, which are devoured (so to speak) by a slow inflammation characterized by intermittent extensions. One may take account of the disorders it causes by the state of intelligence of the patients. At first the inflammation produces an intellectual excitation, which expresses itself in mad acts. Each time a fresh access of madness is observed, one may pretty surely infer a new extension of the disease. But at length, when the whole outer surface of the hemispheres is destroyed, there is no longer either thought, or will, or instinct; the unhappy subjects are plunged in a state of somnolence and stupor, from which nothing can rouse them. They do not speak, because the organ of thought no longer exists.
It is probable, then, that between the organ of thought and the vocal organ there is a third organ—the organ of words, and it is a lesion of this which properly constitutes aphasia.—English Mechanic.