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The areas concerned in language include both sensory and motor areas. These areas of different but related function are found rather widely distributed over the cortex. They occupy parts of almost or quite all of the overflow areas, including certain areas in the right cortex as well as the left. The auditory overflow extends posteriorly toward the occipital lobe, inferiorly on the surface of the temporal lobe, and upward toward the parietal lobe, from the posterior part of the temporal lobe. (Figs. 12, 14.) That part of the upper and middle temporal convolutions which is continuous with the anterior occipital lobe and the inferior parietal lobe of the left hemisphere is concerned in the memories of the sounds of words and of their significance. Injuries of this area cause loss of the power to understand spoken words, though no deafness is present. The person so injured has the same relationship to his mother tongue that normal people have to a foreign language. The words may be distinctly heard, but they have no significance. This area seems to be the one primarily developed in the beginning of the use of language. It is not well developed in idiots of the lower classes, among whom there is no possibility of learning to understand more than the simplest heard language. Lower-class idiots are not capable of using spoken language in the expression of thought, though they may use a few simple expressions indicative of their wants or their affectional states. Very closely associated with the auditory language
area is the motor language area. This occupies the foot of the third frontal
convolution, or Broca’s convolution, as it is called This area lies within
the motor overflow for the laryngeal muscles, and the muscles of the tongue,
lips and face. The motor speech area is associated with the auditory speech
area by the superior longitudinal fasciculus. This bundle is composed of
the axons of cells of the auditory overflow, of the visual overflow and
of the somesthetic overflow, as they pass to the frontal lobes, to form
synapses with cells of the frontal cortex. By means of this bundle the
cells stimulated by the memories of words and their significance are able
to initiate the activity of the motor speech center at the foot of the
third frontal convolution, as well as certain other adjacent areas to be
mentioned later.
The motor speech center is developed with the beginning of active speech. The activity of this center must depend upon the activity of the auditory speech center. In disturbances of the motor speech center the person is able to remember how words sound, and he knows what words to use, but he is not able to coordinate the movements needed for their pronunciation. He is not able to think of the movements needful for the pronunciation; in other words, his motor speech memories are lost. (Fig. 14.) Cases of actual paralysis of the speech muscles are recorded. In these cases speech is lost, but the motor memories remain. The patient is able, in these cases, to form a mental image of the movements needful for speech, but the movements are impossible. The cortical lesions found in such cases involve the inferior part of the precentral convolution. In other cases paralysis of the muscles of the larynx, lips, tongue, etc., may be associated with injuries of the lower centers. The motor speech center is concerned in the first
use of language, in the normal person, and it is subject to stimulation
by the other centers. At first, the development of the centers used in
writing and in other forms of expression are initiated by way of the motor
centers. As development of the secondary center proceeds, the activity
of the first motor center is either not initiated by the transmission of
impulses through it on the way to other centers, or the impulses come to
be carried by other shorter paths, which do not include the original center.
It is noticed in poorly-educated people, who write with difficulty, that
the movements of the fingers are associated with movements of the lips,
tongue, etc., which are concerned in the pronunciation of the words they
are writing. This is true of children learning to write. It is only when
the impulses concerned in writing have become able to travel a pathway
which either does not include the motor speech center, or to traverse that
center without causing its stimulation, that writing becomes easy and as
if without thought for the act itself. This is, of course, the ideal of
expression, that the means of expression should be apparently without thought,
and that only the thing to be expressed should be represented in consciousness.
There is certain clinic evidence that in learning
a new language new neuron groups are functionally developed. At first,
as new languages are usually taught, the impulses are carried by way of
the older center to the neighboring neuron groups. This is the case in
the process of increasing the vocabulary of the language already used.
The new language is not to be considered as learned until it is possible
to express thoughts by the use of the new language without reference to
the old one. Thus, the habit of learning a new language by translating
the words of the old language into the words of the new necessitates the
transmission of the impulses underlying the thought to be expressed to
the auditory speech center, then to the motor speech center, where are
placed the cells for the coordination of the muscle movements of the words
of the language already familiar; then the impulses must be sent from this
center, either directly or, more probably, by way of the center for the
memories of words heard again, to the neuron groups, themselves in the
motor speech center, but somewhat removed from those already educated.
All of this transmission of impulses requires time and nervous energy.
In the process of this transmission the neuron activity concerned in the
consciousness of the thing to be expressed is partly inhibited, and the
thought suffers greatly from this loss of proper coordination. In this
method of learning a new language it is hoped that ultimately the impulses
concerned in the new motor speech center may come to be primarily initiated
without reference to the centers concerned in the older speech movements.
But this shortening of the paths requires a great deal of time, and under
certain circumstances is never perfected.
Recently the so-called “natural method” has been
used in the teaching of new languages. The attempt is made to establish
from the very first a relationship between the thought and the expression
in the new words. No attempt is made to translate one language into another;
in fact, all tendencies to such translation are discouraged. In teaching
by this method the student sees an article and is told the name for it;
sees performed, or himself performs, an act, and is told the word for the
act; perceives qualities of any sort, and is told, and pronounces, the
name for those qualities. In order to prevent the tendency to the translation
of words from one language into the other, objects, qualities and acts
with which the student is not familiar are chosen as much as possible at
the beginning. Idiomatic expressions are employed in the beginning; these,
of course, are not capable of literal translation. The economy of this
system is apparent. No time is consumed in forming a series of paths by
way of the old language centers to the new. Paths which must be finally
eliminated if the new language is to become an efficient means of expression
are not formed, but the connections between the ideas to be expressed and
the motor impulses for their expression are made by the shortest possible
pathway from the very first. The use of the new language learned in this
way becomes easier, the idiomatic constructions seem simpler, and the person
thus taught has better command of the new language than if he had been
compelled to translate the new ideas into the old language first, the into
the new.
The application of this question in therapeutics is apparent. In dealing with those people whose long illnesses have affected the tenor of their thoughts in such a way as to prevent normal mental activity, it is of little value to try to translate their present ideas into healthy expressions and thoughts. In such cases the wisest thing is to try to teach, as if from the beginning, the expression of new ideas. It is like learning a new language for these people to use the expression of cheerful, and pleasant, and wholesome ideas. They must be educated into the expression of useful and healthful ideas by means of wholesome activities, and the use of the words and expressions characteristic of the saner mentality. Fig. 14. The language
centers.
The center for the memories of the appearances of words lies upon the occipital lobe, just posterior to the center for the memories of heard words; that is, in the left angular gyrus. Injury of this center causes visual sensory aphasia. The patient loses the power to recognize words as seen, though there is no true blindness. In uncomplicated cases the patient would yet be able to recognize the significance of words heard, but the proximity of the two centers renders uncomplicated cases of visual amnesia or of auditory amnesia extremely improbable. (Fig. 14.) These two centers are as intimately related in function as they are in location. Both are essential to the performance of the normal writing movements. As in the case of learning a new language, however, the methods of teaching writing should depend as little as possible upon an endeavor to translate the vocal motor speech impulses into the writing motor impulses. The endeavor should be to develop the coordinate activity of each center independently. The motor center for writing lies near the foot of
the second frontal convolution. Lesion of this area is associated with
a loss of the power to write, though the power to read things written is
not lost. (Fig. 14.) The muscles of the hands and fingers are not paralyzed.
The only loss is of the power to coordinate the movements in such a way
as to produce written words. This loss of coordination, in one of Gordinier’s
cases, did not affect the ability of the patient (a woman) to knit. She
was able to hold her pen properly and to make movements which looked as
if she were writing, but only unrelated curves were produced by the movements.
The memories for the appearance of the words and the power to read intelligently,
both silently and aloud, were not injured. The lesion was found, at autopsy,
to involve only the foot of the second frontal convolution.
The angular gyrus of the right hemisphere is concerned
in the memories of the uses, and perhaps also of the names, of objects.
Injuries of this area cause mind-blindness. Objects are distinctly seen,
but are not recognized; their names are not known and their uses can not
be remembered. The condition may be associated with word-blindness, or
it may be uncomplicated. The intimate association of the lateral areas
renders uncomplicated cases rather rare.
The normal activity of the speech centers, as of the other parts of the cortex, depends upon the maintenance of the normal nutritive conditions, and upon the normal relationship of the sensory, associational and motor impulses. It often occurs that the action of these centers, especially of the motor speech center, is incoordinated. This may result from any one or more of a number of different causes. Children who have been made self-conscious and awkward by excessive criticism, especially of an unkind nature, often begin to stammer. This is due to the inhibitory effect of the overstimulated frontal centers. Such inhibitions affect the speech centers in such a manner as to postpone the activity of certain neurons, while the stream of impulses associated with the idea to be expressed stimulates the same center to increased activity. Hence the irregular and incoordinated movements of the vocal muscles may be caused. Emotional states affect the speech mechanism adversely. The inhibitory impulses from the basal centers may be so powerful as to inhibit completely the power of speech. This is especially true of spoken language, though the same effect may be found in written language at times. Stammering may be caused from the presence of certain peripheral irritations. Abnormal sensory impulses may reach the cortex from almost any part of the body in such numbers or such force as to affect the entire cortical activity. Increased irritability results from excessive stimulation, in the absence of exhaustion, and the increase in irritability causes increased activity under slight stimulation. The inhibitory impulses mentioned in connection with the results of excessive adverse criticism are present as a result of excessive sensory stimulation. The presence of poisons in the blood stream, eye strain, overwork, excessive responsibility in children, and a number of other sources of abnormal functional activity on the part of the cortical neurons may be efficient factors in perpetuating the stammering habit The cure of stammering must depend upon the removal
of the abnormal nervous irritations, if any are present, and the education
of the centers.
The stammering person should be taught, first of
all, to recognize vividly in consciousness the actions which he performs
in the endeavor to speak. He should stand before a mirror, at first in
the presence of the doctor who has his case in hand, and should watch himself
trying to talk. He should do this until he is able to see clearly exactly
what manner of motions he is performing. This should be done in as kindly
a manner as possible; no ridicule should be permitted, and no person should
be present except those who must be. Preferably only the doctor in charge
of the case should be with the child when instruction is being given, especially
at the first.
The person in whom the speech centers have been acting in an incoordinated manner for any length of time is very apt to have a certain amount of difficulty in speech under emotional stress or times of fatigue for all his life. If this knowledge inculcates a certain amount of self-control, perhaps no great harm is apt to result from the slight impediment. It must be noted that the motor speech center occupies
part of the third frontal convolution, that the writing center occupies
part of the second frontal convolution, and that the visual overflow and
the auditory overflow are all concerned very markedly in the nervous mechanism
of language. The naming of words, object, actions and qualities makes the
language mechanism associated with practically all of the cortical areas.
So intimately is this language mechanism associated with other parts of
the cortex that the most efficient activity of the cortical neurons depends
upon the exactness and efficiency of the naming process.
In myths of every people whose myths have been studied in this connection there are found accounts of the efficiency of this naming process. In most myths there is a ferocious monster, or some devil, or some malevolent creature who assails, or attacks, or harasses a person or a country. Some wise or brave person calls him fairly and plainly by name, whereupon the malicious creature disappears with a howl, or the devil with an odor of brimstone, or the monster may commit suicide. The fact that giving a name to that which is a cause of disturbance lessens the cause for fear has its root in the fact that the naming process, relating, as it does, so many cortical areas, is associated with more efficient cortical activity, and thus with clearer consciousness than would be possible in the absence of language. Exact naming is one factor in securing vivid consciousness of sensory impulses, thus in appreciating the facts of environment and their significance. The use of words of doubtful meaning, or words which have different uses, without a clear understanding of the manner in which they are being used at any given time, the distortion of words from their commonly accepted significance, the endeavor to employ other terms for the sake of euphony, careless language at any time, all of these things make clear thinking, efficient activity of the cortical neurons, practically impossible. Only as spades are called spades is their use in digging clearly appreciated; only as a wrong is clearly seen can it be righted; only as faults are recognized and named can they be eliminated. The monsters of the myths were destroyed only by calling them by name; the monsters of our civilization, of our government, of our profession, of our individual lives, can be destroyed by calling them by name, and in no other manner. In the old myths, the good fairies, the benevolent
gods, the helpful angels, were to be called to one’s assistance if only
one knew their right names. All the good things of life were held to be
at the disposal of the person who was able to call by a true name the spirit
who had them in charge. This, too, is a truth. If the things which are
desired are called by their right names, the manner of securing them usually
becomes evident. It is true that things become often less desirable when
they are called by their right names. But desires which are truly and exactly
expressed become by that very fact rather more attainable, or their impossibility
becomes more certainly evident. The exact naming of ideals, of earnest
desires, of the objects of enthusiasm, is the first long step toward their
attainment.
In the teaching of children the most important factor to be considered in language is that they shall use words in their exact sense. Many words have more than one meaning; children must be taught to discriminate, and to know in what significance they employ the word. The time of childhood is the time for the teaching of the foreign languages and for the establishment of a large vocabulary. There is a certain educational value in the process of learning a new language. The use of the different neuron groups gives a broader field for the associational activities. The use of the vocabularies associated with the different vocations of life is of similar value, but this is less efficient than the use of the new language. The development of different neuron systems which is secured by the attainment of a new language is not to be found in any other line of education. In the training of the mentally deficient, attempts
should be made to increase the vocabulary in as great a degree as is consistent
with the powers of the child to understand the words. The words chosen
must always be those for which a clear use is possible, and the child must
use them in their exact sense. The more vividly the words can be appreciated
in consciousness, and the more exactly the expressions can fit the thought
to be expressed, the better is the educational value of the language in
the development of the mental capacities.
The use of language as an educational factor in therapeutics is fairly evident. When people are for a long time sick they are apt to become accustomed to answering those foolish questions concerning health which politeness seems to demand by a detailed and more or less truthful account of their sufferings. Now, the very fact of detailing symptoms lowers the liminal value of the neurons concerned in the appreciation of the discomforts, and thus increases their irritability. So that every time the sick person tells his pains to his neighbors, he adds just so much to his own discomforts, he increases the tendency of his neighbor to suffer in the same way, and he postpones certainly the hour of his own recovery. The neighbor usually listens with only half an ear, since he usually is thinking of the pains he himself has suffered, and is getting his thoughts in order for their recital, or he may frankly be bored by the uninteresting tale. This lack of sympathy does a certain amount of good, that it prevents too great an amount of the psychical contagion of suffering. Such people may need nothing in all the world so much as to forget their discomforts, and yet this is the most impossible thing for them to do. “I never allow myself to think of my sufferings, no matter how bad I feel. I just make myself forget it.” People who talk in that way are remembering, and suffering, and making themselves suffer all the day and most of the night. No one can ever forget by determination. The only forgetting comes by way of new and different remembering. If any one would empty a pail of air, he would best do this by filling it with water. The cortical neurons are constantly active. It is impossible to voluntarily prohibit the activity of any particular group of neurons. The neuron groups are stimulated according to their relative liminal values. If any neuron group has the lower liminal value, it is more affected by incoming stimuli. If it is desired to lower the liminal value of other and antagonistic groups of neurons, this is easily done. But it is probably impossible to increase directly the liminal value of neuron groups. So it is of little value to try to teach such people to try to forget their sufferings; they must actually forget them in the use of other neuron groups. It seems to be very successful in some cases to compel the patient to actually lie himself out of his pain. But there must be some lack of normal conditions in the person who is thus able to lie to himself, and the effect of deliberate self-deceit must be harmful. This attitude is unnecessary. There are enough good things in the world to think about without devising false things which are merely supposed to be good. Let the ideas of personal comfort or discomfort alone. It is not good even to attend to bodily sensations long enough to deny them. Let them alone. Let the patient attend carefully to things outside of his own bodily condition and tell others about them. Let him put into words everything which he can find which concerns things strong, and fine, and beautiful. He must not try to think himself well, or talk about himself as well, but he may think of himself as going to work, as engaging in some line of endeavor in which he is interested. He may plan for the future as much as he will, but he should cease at once and absolutely any consideration of his present feelings, either good or bad. He must answer the questions the doctor asks, but to every one else the question of personal sensations should be tabooed. Why should it be polite to ask after a person’s health any more than after his bank account? Persons who are ill for any length of time should be absolutely forbidden to answer any questions concerning their bodily states, or to permit others to talk about the subject of health or sickness. After recovery seems fairly well advanced, it may seem advisable to permit the expressions of strength and good health. The expressions of interest in work or play must always be of greater value than expressions of returning health, however good this may be. The best thing in the world for such people is for
them to begin to plan for the future. Make them talk about the future,
about the things they are planning. Make them talk about the emergencies
which they may meet, and how they will meet them. Make them use the larger
muscles, as has been explained in a previous chapter. Make them talk even
about other people, if they can not be interested in things better fit
for conversation Better the most exaggerated village gossip than talk about
their own physical conditions.
Physiologically, language serves much the same purpose which is served by muscular movements. It gives expression to the nerve impulses arising from the activity of the ganglionar centers and the intermediate areas, and thus eliminates the harm of the repressed emotions and judgments. The development of the neurons of the language centers makes possible the storing of memories and determinations in a more exact and powerful manner than is possible in the absence of language. In education and in therapeutics the language centers may be used as efficiently as are the other cortical or the ganglionar centers. In treating certain diseases characterized by mental symptoms the language centers may be employed, as osteopaths already are employing the spinal centers, for the modification of nervous activity, and thus, indirectly, for the improvement of the bodily state. |
