Psychology
Chapter 3: A Sketch of the General Relations of Consciousness to Neural Action
James Rowland Angell
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It will greatly facilitate our subsequent understanding of the operations of consciousness if we pause to examine at this point some of the things which the nervous system is able to accomplish without the direct assistance of the mind, together with certain general relations of consciousness to neural action. Such an examination will bring us face to face with one or two of the fundamental principles, or laws, which control neural action.
A Matter of Terminology.-- Let it be understood once and for all that wherever we speak, as occasionally we do, as though the mind might in a wholly unique manner step in and bring about changes in the action of the nervous system, we are employing a convenient abbreviation of expression which harmonises with the ordinary everyday methods of thinking and speaking about these relations. The real fact appears to be, as we observed in the previous chapter, that whenever we have mental activity, we have also neural activity in the cerebral cortex. The basal distinction in the two kinds of nervous action to which we are referring in this chapter is, therefore, not primarily between a form in which the mind suddenly produces changes in the nerves as against one in which it does not, but rather a distinction between certain kinds of neural activity involving consciousness, e. g., cortical activity of the cerebrum, and certain other kinds not involving it, e. g., spinal cord reflexes. To use on every occasion the long modifying phrases necessary to precise accuracy on this matter
(48) would evidently be unduly cumbrous, and so we shall employ the commoner modes of expression, but the fundamental facts which lie behind these convenient metaphors must not be forgotten.
Automatic and Reflex Acts. -- If we take up the general character of neural action from the genetic point of view, we shall have our attention at once called to the fact that the new-born babe does not come into the world so completely helpless as is sometimes implied. There is a small group of acts which the little stranger is at once able to perform. Respiration, circulation, and digestion are three physiological functions which are carried on from the first. They all involve muscular movements, and constitute what are commonly known as automatic acts. The nervous stimulus for such activities is wholly, or in part, within the organism itself. Thus, the chemical condition of the blood may be responsible for changes in circulation and respiration, the presence of food in the stomach incites its digestive processes, etc. We are as a rule under normal conditions entirely unconscious of those automatic activities whose effects terminate inside the organism, although if anything goes wrong with them they ordinarily cause us pain and in this way we become cognisant of them.
Other motions can be excited by stimuli outside the organism. Thus the sucking movements necessary for the child to obtain its food are capable of being aroused by touching the lips. The fingers will clasp firmly any object put into them, an act said to be reminiscent of the days when our ancestors lived in trees, and the young had to cling to the branches. Acts of this kind are called reflex. A reflex act, as we remarked in the previous chapter, is definable as an act in which a movement is made in direct response to a stimulus outside the organism, without the interposition of consciousness. Of course consciousness sometimes takes cognisance of reflex acts, but it does not produce them. We may be conscious that
(49) we have winked, and still the closure of the eyelids be due to a reflex. We are very unlikely not to remark that we have sneezed. Oftentimes, however, reflex acts escape our notice altogether, just as the automatic acts do.
Now such acts as these, few in number and simple as they are, evidently furnish the child with a nucleus of coordinations by means of which to begin the conquering of his world. They are evidently hereditary and, as every normal child possesses them, we may regard them unhesitatingly as racial, or phylogenetic, in nature. The animals generally possess at birth a larger equipment of such inherited coordinations than does man, and certain ones we commonly call instincts. These instincts we shall have occasion to examine with greater detail at a later point in the book, so we may pass them by here with the single remark that they are, as regards their origin, undoubtedly akin to the reflexes and the automatic acts. They represent thus the outcropping of the universal racial characteristics in the individual.
Development of Reflexes.-- Were we to observe closely the growth of any child, we should find that from time to time new reflexes were added to his original stock. Thus, winking and sneezing would after a time put in an appearance, and finally at about twelve or fourteen years of age the full store of these reflexes as displayed by the adult would be complete. This course of development undoubtedly runs parallel to the development of the several nerve centres and the intercommunicating pathways.
Continuous Nature of Organic Activity. -- In the light of the foregoing statements it may, perhaps, arouse no special surprise, although it is certainly a striking thing, that from the moment of birth until death there is never complete quiet throughout the organism. Always do we find muscular movements, always something is being done, always activity of some kind is going forward. In sleep itself, which we commonly associate with complete repose, respiration and circula-
(50) -tion are occurring, and although each specific muscular contraction is followed by a period of recuperation for that particular muscle, viewing the organism as a whole there is never entire quiet. When awake, these automatic activities are augmented in the new-born child by such reflexes as we have mentioned. The reflexes naturally occur but infrequently and as for consciousness, it appears during the first weeks of a child's life only for brief periods, most of the time being devoted to deep sleep. Nevertheless, the points at which it does appear are of fundamental importance for our correct apprehension of its function, and we must examine them with care.
The Appearance of Consciousness. -- Evidently the equipment of coordinations with which we have found the new-born infant supplied cannot carry him very far in his adjustment to the complex surroundings amid which he finds himself placed. Why he should have been limited by nature to just the special group of inherited coordinations which we observe in him, is a question for the biologist to answer. We cannot at present go behind the facts. But it is clear at once, that in our list of muscular activities over which the babe has control, there is no mention of means for responding very effectively to auditory or visual stimuli, to mention no others. A closer inspection of the situation will suggest to us the generalisation, which is undoubtedly correct, that we shall find consciousness appearing at those points where there is incapacity on the part of the purely physiological mechanism to cope with the demands of the surroundings. If the reflexes and the automatic acts were wholly competent to steer the organism throughout its course, there is no reason to suppose consciousness would ever put in an appearance. Certainly consciousness would ever put we never find it intruding itself where these conditions are observed, except in pathological instances.
Let us examine as a typical case what happens when the consciousness of sound first occurs. We know that many chil-
(51) -dren are unable to hear for several days after birth, partly because the middle-ear is filled with mucus. When the time comes, however, that the ear is able to receive the auditory "stimulus, we have at once an excitation of the organism for which there is no definite preformed muscular response. Some children, to be sure, early display a tendency to move the head, as does an adult in localising a sound, and this may possibly be a partially hereditary propensity. But it is problematic whether this ever occurs immediately after birth, and certainly it is quite rare. The usual thing under such conditions is unquestionably the appearance of vague consciousness dominantly of the auditory kind; the stimulation having the tendency, if it be intense, to discharge itself according to the law of "diffusion" (of which more anon) throughout many motor channels, involving movements of the muscles in various parts of the body.
Now these movements require coordination. If they are ever to be turned to account they must be controlled and ordered. The new stimulus has broken rudely in upon the coordinated reflex and automatic activities already going on. It has probably affected the circulation and the respiration. If the child were feeding, it may have shocked him into cessation and, in place of the sucking, set up the unwelcome wailing. Such a case is typical of the occasions where consciousness comes to light. The organism has end-organs sensitive to sound stimulations, but no ready-made physiological arrangements for responding effectively to such stimuli. Consequently, when a stimulus of sound bursts in upon its activities, some of which, as we have seen, are always in progress, it finds itself helpless and unable to act in any save a random and disordered way. Straightway appears consciousness with its accompanying cortical activities, taking note of the nature of the stimulus and of the various kinds of muscular response which it called forth. From this point on, the development is steady and uninterrupted toward the at-
(52) -tainment of those fixed and intelligent modes of reaction, which we call habits.
Were we to examine in the same way the appearance of visual consciousness, we should find a precisely similar state of things, save that in this case the fully developed process involves certain reflexes which are not perfectly matured at birth, like the accommodation of the lens of the eye. But the essential point is the same. Consciousness appears in response to the needs of an organism sensitive to certain kinds of physical stimuli, i. e., in this case light. These stimuli breaking in upon the operations of the organism find it incompetent to cope with them immediately. It has the power of making movements in response, but none of those which are inborn meet the case, and among all the other potential ones there must be intelligent adaptive selection. This is the field of conscious action, and we should find, were we to take time for a thorough exploration of all the sensory forms of consciousness, e. g., taste, smell, touch, etc., that they are all called forth, under the same conditions of inadequacy on the part of the purely hereditary physiological mechanisms of movement, to meet the demand of the physical and social environment.
It shall be our next business to trace in outline the process by which consciousness brings order out of this threatened. chaos and leaves the organism a group of habits to which additions are continually made and by means of which the organism becomes increasingly master of the situation. This account will be only a sketch, however, for all the rest of our study will really be devoted to filling in the details. In the chapters upon volition we shall return specifically to these very points.
The Formation of Habits. -- It will be remembered that in the previous chapter, when we were studying the nervous system, we observed that in its simplest forms the nervous organism appeared to be little more than a device to connect
(53) a sense organ with a muscle and so to enable the discharge of movements in response to stimulation. When we examined complex systems, like that of man, where memory processes are clearly in evidence, we noticed that this same principle was everywhere in evidence, although it gained its expression through the most elaborate arrangements in the nervous tissues. We remarked, also, that the normal fate of every incoming sensory stimulus was to find its way out again sooner or later in the form of muscular movements and glandular activities. This tendency is in no way modified by the complexity of the neural structure, except as regards the ease with which we detect such reappearance of the stimulus in the form of motion. If we bear these facts in mind, a considerable part of the mystery seemingly surrounding the processes we are now to investigate will fall away at the outset.
The Beginning of Motor Control. -- Let us take as a typical instance of the development of motor control the series of events which occur when a baby first learns to connect a visual impression with a movement of his band and arm. Suppose a bright, coloured ball is held before his eyes. This stimulus sends strong sensory currents over the optic tracts to the brain centres and somehow or other, as we have seen, these currents must get out again in the form of movements. But we have also seen that there are few or no preformed reflex pathways over which such neural excitement may be discharged. Consequently, instead of some single relatively simple movement like that of reaching, what we observe is precisely what the principle of " diffusion " postulates as normal, i. e., a mass of aimless, uncoordinated movements in a large number of muscles. The face is wrinkled in a frown or a smile, as the case may be, the fingers open and shut the arms jerk about, the body and legs move spasmodically and possibly the child cries out. This does not seem a very promising beginning for the development of intelligent
(54) control, and yet in point of fact it contains just the features most essential for progress. Speaking generally, we may say that such stimulations call out an excess reaction, a motor response in which are contained, almost without fail, the special small group of useful and important movements which subsequently become isolated from the general miscellaneous motor matrix in which they at first appear. The manner in which this result is attained we can detect by observing our illustrative baby still further in the light of our knowledge of how we, as adults, acquire new coordinations.
Presently, if the stimulus be made more exciting by moving it to and fro, some of these excess movements of the arms will result in the child's hand coming into contact with the ball. We have already noted the hereditary clasping reflex, and we shall not be surprised, then, to find that the tactual stimulus to the skin of the hand Yes-tilts in the closing of the fingers. Now undoubtedly this first successful grasping of the seen object may be wholly accidental, in the sense that it is wholly unforeseen by the child. He is much more surprised by the occurrence than any of his interested observers, who accredit him with a wealth of conscious purpose and intention of which be is completely innocent. But let us observe what fundamental consequences are bound up with this success.
In the first place, the mere shock of surprise and (generally) pleasure makes the connection of the tactual-motor sensations from his hand with the visual sensations from his eye extremely vivid. As lie moves his hand, be finds his visual impressions change. When his hand comes to rest, his visual object also remains quiet. There is no reason to I
pose that the child is in any definitely reflective way aware of these things. He does not say to himself: "When I see my hand move, I see the ball move; therefore, the two things are connected in some way." Indeed, it is probably impossible for it- in adult life. to portray accurately to ourselves
(55) the simple immediacy of such experiences as these in infant life. But the important point, after all, is this, that of all the sensations which his whole acquaintance with the ball has brought the child up to this point, the ones connected with -his seeing it when he grasps it, and his seeing it change when .his arm-and-hand-feeling changed, are the ones most intensely connected in his consciousness.
if we read backward into his mind, then, what we all know about our own adult experiences, we may be sure that the child's memory is extremely likely to retain the highly vivid connection of the visual sensations of the ball with these tactual-motor feelings which accompanied the successful grasping of it. Moreover, the genuineness of this connection is indicated by the evident tendency to make the successful kind of arm movement, rather than any of the dozens of other movements with which he started his response to the ball, provided we give him at once an opportunity to get again the same visual impression from which he set out. To be sure, many of the irrelevant movements persist for a time, but they rapidly become less frequent and finally disappear. The perfect result is of course rarely attained without many trials. In this way, however, the child speedily does for himself what nature did in the case of the reflexes, i. e., gives himself a neural pathway through which sensory impulses may flow out over motor channels for the production of effective coordinated muscular movements. In this case we have observed the establishing of a control connection between eye and hand. The sight of the ball will henceforth tend to call out the appropriate reaching and grasping movement.
The more firmly this connection becomes established, and the more deeply the pathway is cut between the visual sensory 4 centres and the hand-arm motor centres, the more do the irrelevant movements of face, legs, and body tend to drop away. They are inhibited, as we say. Probably this inhibition is in largest measure due to the fact that the newly formed channel
(56) is increasingly able to carry off all the neural excitation, and in consequence less remains to overflow into other channels. But the result is certainly beyond question, whatever the means by which it is attained. Moreover, just in proportion as any such coordination becomes perfect, consciousness tends to drop out of the supervision altogether, and to turn the process over to the purely physiological mechanisms of the organism. Figure 32 illustrates certain of the relations which have been described.
Characteristics of Habit. -- The nervous system is not only sensitive to the various forms of stimulation which we call light, sound, temperature, etc., it also manages in some way or other, as we have already observed, to store up the modifications which the stimulations produce in it. These modi-
(57) -fications which are thus preserved manifest themselves in the disposition of nervous impulses to run in the same channel which predecessors have cut out. If the nervous system were an inanimate mass, we might liken that which occurs to the process by which a path is made across a meadow. The first wayfarer may have selected his special route for any cause whatsoever, and his course may have been devious, like those of the cows which are said to have laid out the streets of Boston. But he has left a mark in the downtrodden grass, which the next person to cross the field is likely to follow. Presently the grass is wholly worn away, and thereafter every- one follows the beaten path.
The action of nervous impulses is often spoken of as though this kind of thing were precisely what happened. But the moment we recall the fact that the nervous system is part of a living organism, in which processes of nutrition and repair are constantly going forward, and within which many intraorganic changes are producing from moment to moment relatively new conditions, we see that the metaphor of the pathway in the meadow must be abandoned in favour of some idea in which the vital processes of the organism are recognised and the living tissues treated as something other than so much static, plastic clay, which the accidents of the external world can mould to their own exclusive purposes. It is undoubtedly true that when avenues, or channel, of nervous activity become once established, they tend ever after to remain and be employed. But the point which we must emphasise is, that the organism itself largely decides which pathways shall in the first instance become thus established. When one recalls the large number of sense organs on the one hand, and the large number of muscles on the other, between which the central nervous system affords connections, it will at once be appreciated that, if the establishment of dominant connections in the new-born child were left to the accidents of the first external stimulations and to the vagaries of merely pas-
(58) -sive nervous centres, the chances would favour the acquirement of insane and harmful habits of reaction. Objects which burn would be just as likely to produce movements of grasping as movements of retreat.
We may summarise the general purport of habit as a fundamental principle of nervous action in two propositions. (1) Nervous currents tend to employ those pathways which have been previously employed. (2) The organism itself plays a governing part in determining what pathways shall become thus fixed.
Results of Habit.-- The advantages which accrue from habit are almost self-evident. When we compare such habitual coordinations as are involved in writing the familiar English script with those employed in writing the German characters with which most of us are far less familiar, we note that the former letters are much more rapidly executed, that they are much more accurately made, and that they produce far less fatigue. It is evident, therefore, that habit is a most valuable contributor to efficiency in action. Any process which increases speed and accuracy, while at the same time it diminishes the fatigue of labour, is a possession to be cherished.
But more important, if possible, than any of these results is the fact that through the mediation of habits the physiological organism is enabled to cope almost unaided with situations which originally required the assistance of conscious processes, and consciousness is thus left free to go about further attainments, which will in their turn become habits and be handed over to certain of the relatively non-conscious processes of the nervous system. Consciousness is thus ever going on in advance and building up coordinations, which are necessary to the most effective reactions upon the environment. The whole course of mental development could truly enough be described as made up of this process of acquiring habits, which once imbedded in the tissues of the nervous system become
(59) the permanent possession of the individual, ready, when need arises, to step in and deal with the necessities of any particular situation.
Acquired and Hereditary Habits.-- If we now look back over the ground covered in this chapter, we shall see that consciousness occupies a curious middle-ground between hereditary reflex and automatic activities upon the one hand and acquired habitual activities upon the other. The organism comes into the world with a small capital of these hereditary coordinations. These suffice to meet the most immediate and pressing needs in the conservation of life, but they are hope. lessly defective for the attainment of anything beyond these immediate necessities. Now and again the world of light and sound and contact breaks in upon the coordinations which our hereditary neural mechanisms are executing, because the adaptive responses made by these mechanisms are inadequate to the organic necessities of the situation, and at such points we find consciousness appearing. Consciousness immediately enters 'upon its characteristic cycle. At first of course its activities are vague and crude. But presently it has selected from out the masses of motor responses created by the sensory stimulations to which the sense organs are sensitive, those particular ones which issue in effective muscular control over the environment, and straightway we are confronted with habits. As soon as these habits are firmly established, consciousness betakes itself elsewhere to points where habitual accommodatory movements are as yet wanting and needed.
Thus the progress of events is marked by the emergence of consciousness from a matrix of movements which are apparently unconscious and hereditary and its disappearance again after a period of activity in the creation of the quasireflexes, which we call habits. It is an interestin- fact incidental to this development, that when we attempt to inject consciousness into a process which is either reflex or habitual, we upset the accuracy of the coordination and mutilate its
(60) efficiency. Thus, to direct attention to the act of swallowing, which is a reflex, is to render it for many persons all but impossible of performance. Witness the common difficulty in taking pills. Similarly, to direct attention to one's mode of walking often results in producing a thoroughly artificial gait quite unlike one's normal manner. The early experiences of appearance before the public, as on the stage, also illustrate this point.
Habit and Will. -- Although we do not commonly think of it in this way, a moment's reflection will show us that all expression of the will depends upon our ability to command habitual muscular coordinations. For example, I decide after careful consideration that duty bids me refuse a friend's request. Now note, that if I speak to my friend, I must fall back upon habits of articulation, which cost me much labour as a child to attain, but which now largely take care of themselves. If I decide to write my decision, again I must employ habitual activities, and I cannot by any device communicate intelligibly with my friend without employing these or other similar muscular movements which are essentially habits. Neural habit, therefore, is not only the great emancipator of consciousness from the necessities of endless control over the same trivial round of acts, it is the great tool by which that feature of consciousness which we call the will executes its behests and renders our mental decisions and choices effective in the world of action. Without habits, consciousness could never get beyond the borders of the inevitable daily routine. With habit, however, it is able to pass from victory to victory, leaving behind in captivity the special coordinations it needs.
Intellectual Habits.-- We cannot linger to develop the matter, but it may be helpful simply to point out that the mastery of any subject matter, such as mathematics, for instance, involves a precisely similar establishment of habits, which, as the material is thoroughly mastered, are left behind for use when required. We do not ordinarily regard such attain-
(61) ments as concerned in any fundamental manner with muscular movements, although we all recognise readily enough that the sole manner of assuring ourselves a reliable command over a subject matter is to use it, to do something with it. We sometimes think of such doing as purely mental. In reality, however, movements are involved in all cases, and, even were this not true, the general principle of habit, so far as this stands for a law governing the transmission of nervous currents, would still be valid. The gain in rapidity, efficiency, and lessened fatigue would remain, not to mention the freeing of consciousness for further achievements.
Apart from such command over special departments of information, what are known as " habits of thought," which we are often vaguely told we ought to cultivate, are in reality largely habits of exercising our attention. We are assured, for instance, that the pursuit of certain studies is valuable because it will teach us desirable habits of thought. Now when this assurance means anything more than the expression of a pious hope, it refers either to the attainment of a familiarity bordering on habit, with a useful field of information, or to the securing of general modes of approaching a new subject matter; habits of alert attention, habits of logical division and persistent search for relations, etc. Whether any special studies are preeminently valuable in the production of this second class of results is a question which can be answered more judiciously, if at all, at the end of this book. Meantime, we shall not err seriously if we assert that a wholly fallacious value has often been placed upon so-called formal disciplines, which are supposed to teach us how to do things in general, without any special reference to accomplishing particular results.
Ethical Aspects of Habit.--The moment one gets clearly in mind the physiological nature of habit and its basis in the nervous tissues, its ominous significance for morality becomes evident. To break up a bad habit means not only to secure a
(62) penitent, reformatory attitude of mind, -- this is often easy to achieve, -- it means a complete change in certain parts of the nervous system, and this is frequently a thing of utmost difficulty of attainment. No amount of good resolution can possibly wipe out at once the influences of nervous habits of long standing, and if these habits are pernicious, the slavery of the victim is sure to be pitiable and likely to be permanent. On the other hand, the momentous significance for the individual and society of deeply imbedded habits of a moral kind cannot be overestimated. The existence of such habits means stability, reliability, and the promise of the utmost possible confidence. It is all but impossible for one to break over the moral habits of a lifetime. One may at times be mildly tempted by the possibilities such breaches hold out, but actual violation in overt action is essentially impossible. The man who has been vicious all his life is hardly free to become virtuous, and the virtuous man is in a kind of bondage to righteousness. What one of us could go out upon the street and murder the first person he met? Such action is literally impossible for Lis so long as we retain our sanity.
In view of these considerations, no one can over-estimate the ethical importance of habit. To make the body, in which our habits are conserved, one's friend and ally and not one's enemy is an ideal which should be strenuously and intelligently held out to every young person. One never can say at what precise moment it may become literally impossible to shake off a bad habit. But we know with perfect certainty that our nervous tissues are storing Lip every day the results of our actions, and the time is, therefore, sure to come when no amount of merely pious intention can redeem us from the penalty of our folly. Meantime, for one who has fallen under the sway of a habit he wishes to escape from, this general advice can be given: begin the new regime at once, do not wait for a convenient season. If the result is not likely to be physically disastrous, stop wholly, do not taper off. Give
(63) yourself surroundings which will offer the least possible temptation. Do not try merely to suppress the bad habit. If possible, put something else which is good in place of it. See it that you are always occupied in some proper way until you feel sure that the grip of the bad habit is loosened.
On the other hand, it is to be frankly admitted that viewed in a broad way the benefits of habit have their limitation. If the world always did things just as they have been done in the past our civilisation would approach that of the Chinese. But the changes which by the consensus of intelligent persons are beneficial to mankind, the alterations of habit which are progressive, are rarely such as have to do with those purely personal forms of action whose perversion constitutes the most flagrant form of vice.
Moral progress always consists in a harmonised action of wider and wider interests, the securing of broader and truer visions of life. Such progress, while it may change old and accepted habits of life, does not for a moment involve any departure from those rules of personal honesty, sobriety, and ,chastity which the world's history has demonstrated again and again as the foundations of all sane, happy human life.
