The far-reaching effects of motor expressions are too infrequently emphasized, but psychology forces us to give them prime consideration. We are first apprised of their importance when we study the nervous system, and find that every incoming sensory message pushes on and on until it finds a motor pathway over which it may travel and produce movement. This is inevitable. The very structure and arrangement of the neurones is such that we are obliged to make some movement in response to objects affecting our sense organs. The extent of movement may vary from the wide-spread tremors that occur when we are frightened by a thunderstorm to the merest flicker of an eye-lash. But whatever be its extent, movement invariably occurs when we are stimulated by some object. This has been demonstrated in startling ways in the psychological laboratory, where even so simple a thing as a piece of figured wall-paper has been shown to produce measurable bodily disturbances. Ordinarily we do not notice these because they are so slight, sometimes being merely twitches of deep-seated muscles or slight enlargements or contractions of arteries which are very responsive to nerve currents. But no matter how large or how small, we may be sure that movements always occur on the excitation of a sense organ. This led us to assert in an earlier chapter that the function of the nervous system is to convert incoming sensory currents into outgoing motor currents.
So ingrained is this tendency toward movement that we do not need even a sensory cue to start it off; an idea will do as well. In other words, the nervous current need not start at a sense organ, but may start in the brain and still produce movement. This fact is embodied in the law of ideo-motor action (distinguished from sensory-motor action), "every idea in the mind tends to express itself in movement." This motor character of ideas is manifested in a most thorough-going way and renders our muscular system a faithful mirror of our thoughts. We have in the psychological laboratory delicate apparatus which enables us to measure many of these slight movements. For example, we fasten a recording device to the top of a person's head, so that his slightest movements will be recorded, then we ask him while standing perfectly still to think of an object at his right side. After several moments the record shows that he involuntarily leans in the direction of the object about which he is thinking. We find further illustration of this law when we examine people as they read, for they involuntarily accompany the reading with movements of speech, measurable in the muscles of the throat, the tongue and the lips. These facts, and many others, constitute good evidence for the statement that ideas seek expression in movement.
The ethical consequences of this are so momentous that we must remark upon them in passing. We now see the force of the biblical statement, "Not that which entereth into the mouth defileth the man; but that which proceedeth out of the mouth, this defileth the man." Think what it means to one's character that every thought harbored in the mind is bound to come out. It may not manifest itself at once in overt action, but it affects the motor pathways and either weakens or strengthens connections so that when the opportunity comes, some act will be furthered or hindered. In view of the proneness to permit base thoughts to enter the mind, human beings might sometimes fear even to think. A more optimistic idea, however, is that noble thoughts lead to noble acts. Therefore, keep in your mind the kind of thoughts that you wish to see actualized in your character and the appropriate acts will follow of their own accord.
But it is with the significance of expressions in study that we are at present concerned, and here we find them of supreme importance. We ordinarily regard learning as a process of taking things into the mind, and regard expression as a thing apart from acquisition of knowledge. We shall find in this discussion, however, that there is no such sharp demarcation between acquiring knowledge and expressing knowledge, but that the two are intimately bound together, expressions being properly a part of wise and economical learning.
When we survey the modes of expression that may be used in study, we find them to be of several kinds. Speech is one. This is the form of expression for which the class-recitation is provided. If you wish to grow as a student, utilize the recitation period and welcome every chance to recite orally, for things about which you recite in class are more effectively learned. Talking about a subject under all circumstances will help you learn. When studying subjects like political economy, sociology or psychology, seize every opportunity to talk over the questions involved. Hold frequent conferences with your instructor; voice your difficulties freely, and the very effort to state them will help to clarify them. It is a good plan for two students in the same course to come together and talk over the problems; the debates thus stimulated and the questions aroused by mental interaction are very helpful in impressing facts more vividly upon the mind.
Writing is a form of expression and is one thing that gives value to note-taking and examinations. Its value is further recognized by the requirements of themes and term-papers. These are all mediums by which you may develop yourself, and they merit your earnest cooperation.
Another medium of expression that students may profitably employ is drawing. This is especially valuable in such subjects as geology, physiology and botany. Students in botany are compelled to do much drawing of the plant-forms which they study, and this is a wise requirement, for it makes them observe more carefully, report more faithfully and recall with greater ease. You may secure the same advantages by employing the graphic method in other studies. For example, when reading in a geology text-book about the stratification of the earth in a certain region, draw the parts described and label them according to the description. You will be surprised to see how clear the description becomes and how easily it is later recalled.
Let us examine the effects of the expressive movements of speech, writing and the like, and see the mechanism by which they facilitate the study process. We may describe their effects in two ways: neurologically and psychologically. As may be expected from our preliminary study of the nervous system, we see their first effects upon the motor pathways leading out to the muscles. Each passage of the nerve current from brain to muscle leaves traces so that the resulting act is performed with greater ease upon each repetition. This fact has already been emphasized by the warning, Guard the avenues of expression.
Especially is it important at the first performance of an act, because this determines the path of later performances. In such studies as piano-playing, vocalizing and pronunciation of foreign words, see that your first performance is absolutely right, then as the expressive movements are repeated, they will be more firmly ingrained because of the deepening of the motor pathways.
The next effect of acts of expression is to be found in the modifications made in the sensory areas of the brain. You will recall that every movement of a muscle produces nervous currents which go back to the brain and register there in the form of kinaesthetic sensations. To demonstrate kinaesthetic sensations, close your eyes and move your index finger up and down. You can feel the muscles contracting and the tendons moving back and forth, even into the back of the hand. These sensations ordinarily escape our attention, but they occupy a prominent place in the control of our actions. For example, when ascending familiar stairs in the dark, they notify us when we have reached the top. We are still further impressed with their importance when we are deprived of them; when we try to walk upon a foot or a leg that has gone "to sleep"; that is, when the kinaesthetic nerves are temporarily paralyzed we find it difficult to walk. But besides being used to control muscular actions, they may be used in study, for they may be made the source of impressions, and impressions, as we learned in the chapter on memory, are a prime requisite for learning. Each expression becomes, then, through its kinaesthetic results, the source of new impressions, when, for example, you pronounce the German word, anwenden, with the English word "to employ," in addition to the impressions made through the ear, you make impressions through the muscles of speech (kinaesthetic impressions), and these kinaesthetic impressions enter into the body of your knowledge and later may serve as the means by which the word may be revived. When you write the word, you make kinaesthetic impressions which may later serve as forms of revival. So the movements of expression produce sensory material that may serve as tentacles by means of which you can later reach back into your memory and recall facts.
We shall now consider another service of expressions which, though little regarded, nevertheless is of much moment. When we make expressive movements, much nervous energy is generated; much more than during passive impression. Energy is sent back to the brain over the kinaesthetic nerve cells, and the greater the extent of the movement, the greater is the amount of new energy sent to the brain. It pours into the brain and diffuses itself especially throughout the association areas. Here it excites regions which could not be excited by a more limited amount of energy. This means, in psychical terms, that new ideas are being aroused. The obvious inference from this fact is that you may, by starting movements of expression, actually summon to your assistance added powers of mind. For example, when you are called upon to recite in class, your mind seems to be a complete blank—in a state of "deadlock." You may break this "deadlock" and start brain-action by some kind of movement. It may be only to clear your throat, to ejaculate "well," or to squirm about in the seat, but whatever form the movement takes, it will usually be effective in creating the desired nervous energy, and after the inertia is once overcome the mental stream will flow freely. The unconscious application of this device is seen when a man is called on suddenly to make a speech for which he has not prepared. He usually starts out by telling a story, thus liberating nervous energy to pour back into the brain and start thinking processes. With increasing vehemence of expression, the ideas come more and more freely, and the result is a speech which surpasses the expectations of the speaker himself. The gesticulations of many speakers have this same function, being frequently of great service in arousing more nervous energy, which goes back to the brain and arouses more ideas.
The device of stimulating ideas by expressive movements may be utilized in theme- or letter-writing. It is generally recognized that the difficult thing in such writing is to get a start, and the too common practice is to sit listlessly gazing into space waiting for "inspiration." This is usually a futile procedure. The better way is to begin to write anything about the topic in hand. What you write may have little merit, either of substance or form. Nevertheless, if you persist in keeping up the activity of writing, making more and more movements, you will find that the ideas will begin to come in greater profusion until they come so fast you can hardly write them down.
Having tried to picture the neural effect of expression, we may now translate them into psychological terms, asking what service the expressions render to the conscious side of our study. First of all, we note that the expressions help to make the acts and ideas in study habitual. We find ourselves, with each expression, better able to perform such acts as the pronunciation of foreign words. Second, they furnish new impressions through the kinaesthetic sense, thus being a source of sense-impression. Third, they give rise to a greater number of ideas and link them up with the idea dominant at the moment. There is a further psychological effect of expression in the clarification of ideas. It is a well-attested fact that when we attempt to explain a thing to someone else, it becomes clearer in our own minds. You can demonstrate this for yourself by attempting to explain to someone an intricate conception such as the nebular hypothesis. The effort involved in making the explanation makes the fact more vivid to you. The habit of thus utilizing your knowledge in conversation is an excellent one to acquire. Indeed, expression is the only objective test of knowledge and we cannot say that we really know until we can express our knowledge. Expression is thus the great clarification agency and the test of knowledge. Before leaving this discussion, it might be well to remark upon one phase of expression that is sometimes a source of difficulty. This is the embarrassment incident to some forms of expression, notably oral. Many people are deterred from utilizing this form of expression because of shyness and embarrassment in the presence of others. If you have this difficulty in such excess that it hinders you from free expression, resolve at once to overcome it. Begin at the very outset of your academic career to form habits of disregarding your impulses to act in frightened manner. Take a course in public speaking. The practice thus secured will be a great aid in developing habits of fearless and free oral expression.
This discussion has shown that expression is a powerful aid in learning, and is a most important feature of mental life. Cultivate your powers of expression, for your college education should consist not only in the development of habits of impression, but also in the development of habits of expression. Grasp eagerly every opportunity for the development of skill in clear and forceful expression. Devote assiduous attention to themes and all written work, and make serious efforts to speak well. Remember you are forming habits that will persist throughout your life. Emphasize, therefore, at every step, methods of expression, for it is this phase of learning in which you will find greatest growth.