Studies in the Osteopathic Sciences
The Physiology of Consciousness: Volume 3
Louisa Burns, M.S., D.O., D.Sc.O.
The Function of the Cortex
    The great value of the cortical coordinations lies in the fact that the exceptional occurrences may be met by appropriate answers. The reactions which occur as the result of racial inheritances and developmental processes can take no account of the exceptional cases. The projection of the sensory and motor impulses upon the widespread cortical area, with the infinitely complex fibers and tracts which relate its every part, either directly or indirectly, to every other part, makes it possible for those complex coordinations to occur which are needful for the determination of an efficient reply to the exceptional cases.

    By means of the activities of the intermediate areas, with the inhibitions which become possible through the presence of the complex structure of the cortex and the manifold inter-neuronic connections, the factors of any experience may be dissociated, and the elements of that experience associated with other elements of other experiences, and so on. Thus, the impulses associated with any given series of experiences may serve as a basis upon which may be built other experiences, which, though never present in the history of the individual, may serve him as sources of information, and may modify his reactions as efficiently as if they had been actual experiences.

    This power of dissociating and recombining the elements of actual experiences into new and imaginary experiences, which may act as determining forces in answering the exceptional demands, is the function of the cortical areas.

The Physiological Basis of Reason

    The simplest form of coordination is that found in the action of the centers in the spinal cod, and the homologous centers of the medulla, pons and midbrain. In these centers the nerve cells act according to the impulses reaching them; (a) from the sensory fibers of the same and adjacent spinal segments, (b) from association cells of the same and adjacent spinal segments, (c) from higher nerve centers. The manner of reaction of the spinal centers is affected also by the physiological condition of the cells themselves.

    The various visceral centers of the medulla and pons exemplify the next higher group of coordinating neurons. These centers receive impulses from the sensory neurons of the second order, the nucleus gracilis and nucleus cuneatus, the nuclei of the cranial sensory nerves, and from the higher centers. These centers—heart, respiratory, vaso-motor, etc.—are affected also by the character of the blood circulating through them. The higher development, the more elaborate functioning of the bulbar and pontine centers, depends upon this, that they coordinate the impulses governing a very large part of the body.

Ganglionar Centers
    The different centers of the basal ganglia display a still more elaborate form of oordination. In these ganglia the coordination depends upon the receipt by them of the impulses from ssensory neurons of higher than second orders. In these ganglia the results of the past experiences of the race have affected the relations of the neurons concerned in such a manner that the very appearance of danger in the environment initiates the motor impulses expressive of what in our own consciousness is called fear or anger. In the same way, the receiving by these centers of the impulses of bodily well-being, of comfortable environmental factors, initiates the discharge by these centers of the motor impulses which express what we call pleasure or satisfaction. This relationship between the environmental factors and the condition of the body has been established through ages of experiences. For those ancestors whose coordinating centers were so constructed as to secure the manifestations of fear in the presence of danger beyond the powers of resistance, or the manifestations of anger and the fighting reactions in the presence of danger which might result in victorious combat, were those whose descendants, transmitting that cause of strength, were most numerous and most ready to make use of that strength for the perpetuation of their characteristics.

    The activity of the centers concerned in the instinctive or emotional reactions, as they are variously called, depends upon the inheritance of those structural qualifications which have, in the history of the race, been found to be beneficial. While there is no reason to believe that there is any inheritance of those characteristics which result from the life history of the individual, there is great reason for the belief that there is an inheritance of those qualities which modify the reaction of the individual; in other words, the history itself is not a matter of inheritance, but the qualities which enable the individual to modify his history are inherited. In this sense, then, the ganglia in which are coordinated the emotional reactions retain a racial memory; that is, the manner of the ultimate motor impulses form these ganglia depends upon: (a) the sensory impulses, (b) the impulses from higher centers, mostly inhibitory, (c) the physiological conditions of the neurons concerned, (d) the racial memories as laid down in structural and physiological relationships.

Relations of Centers
    The higher centers differ from the lower in the increasing complexity of the reactions which are coordinated by them, and not in the increasing complexity of the impulses reaching them. The spinal centers are affected by impulses from the sensory nerves of the same and adjoining segments, and also by the impulses reaching them from the higher centers. The higher centers are themselves affected by impulses from over all the body; so the spinal centers may be affected indirectly by impulses from the entire body. Thus, ultimately, the origins of the impulses affecting the spinal centers are as varied and as complex as are the origins of the impulses affecting the cortical centers. But the reactions controlled by the spinal centers are comparatively simple, while the reactions controlled by the ganglionar centers and the cortical centers of the cerebrum are almost of infinite variety.

    The projection of the sensory impulses upon the cerebral cortex is associated with the development of the overflow areas. The visual area occupies the lingual and cuneate gyri, the auditory area occupies the first and perhaps part of the second temporal lobe, the somesthetic area occupies the postcentral gyrus, the olfactory area spreads over the inferior aspect of the brain, involving a number of cortical areas, and the motor area occupies the precentral gyrus.

Overflow Areas
    Probably in part during the development of the centers just enumerated, but chiefly since their fixed representation upon the cortex, there have been developed certain other areas in their immediate neighborhood. The primary sensory and motor areas lie upon the cortex like islands. Not one is continuous with any other, except the primary motor with the somesthetic areas. Thus, between the primary areas lie areas which seem, in animals, to have no known function.

    The term “overflow area” should suggest the picture of nerve impulses reaching the primary area and flowing over into the adjacent cortical regions. Since the areas neighboring upon any primary sensory area are of greater extent than the primary area itself, it is evident that the possibilities of association processes are increased by the presence of the overflows. There are also certain peculiarities of the cell structure of the overflow areas which increase their capacity for associating and for holding in escrow the effects of the stimulations reaching the primary areas.

    With the development of the overflow areas associated with the primary sense areas, the retention of the effects of the stimulation of certain neuron groups is possible. The physiological effect of the stimulation of any neuron or neuron group is the lowering of the liminal value of that neuron or neuron group. The stimulation of any neuron causes the initiation of a cellulipetal impulse over the axon of that neuron, and this impulse affects the neurons with which the axon forms synapses. If the axon forms synapses with a number of neurons, that one will be affected most which has the lowest liminal value. Thus, the stimulation of several neurons in series is associated with a lowering liminal value of the series, and the later stimulation of any neuron in that series is apt to cause the stimulation of the other neurons of the series. This is the physiological basis of memory. The question as to whether anything is ever forgotten, whether memories are stored in some “sub-conscious” reservoir, is puerile. The physiological condition of the neurons concerned is changed, but whether it is possible for the effect thus produced to be completely lost or not is something beyond the human power to determine. Are the fog drops lost when the sun shines brightly? Are the effects of the waves on the sand lost when the tide flows over them? In a philosophical sense nothing is lost; the fog of this morning, the last year’s bird song, the color of yesterday’s sunset, have place today in the effects of their past existence. In such a sense memories are existent, and in none other. As experiences affect the physiological conditions of neurons, the effects of all experiences are, in a certain sense, not lost during life. But it seems scarcely probable that the experiences of a lifetime should remain capable of stimulating the neurons concerned in affecting consciousness during a lifetime. Yet it is not possible to determine what experiences are completely lost and what are merely not recalled.

Interpretation of Experiences
    By means of the overflow areas the elements of experiences are stored, and by the repeated activities of the neurons of these cortical areas elements may be dissociated and recombined, and thus new images may be produced in consciousness. These new images, the result of the dissociation and recombination of elements of past experiences, may be recognized as being part of actual experiences, at times, and under slightly abnormal conditions. The power to dissociate and recombine is a necessary element in the processes underlying intellectual life. Imbeciles fail in this power. The wonderful memory of imbeciles is due to this lack of dissociation. The increased power of dissociation and recombination is found among people of increased imagination When this power is associated with a high degree of functional activity on the part of the posterior intermediate area, such persons are those of great mentality.
Intermediate Coordinations
    The development of the overflow areas precedes the development of the intermediate areas. By means of the activities of the intermediate areas, the memories, the dissociated ideas, and the abstractions resulting from the dissociations of the elements of past experiences are combined into the higher conclusions, the abstract judgments, the classification of the fats and the interpretation of things as perceived in the light of many relationships. By the activities of the intermediate areas hypotheses are formed, deductions are drawn, the relationships of environmental factors are perceived in their wider aspects, and the relation of the individual to his fellowman is decided upon in the light of the wisdom and understanding resulting from the activities of all parts of the cortex.
Anterior Intermediate Areas
    The anterior intermediate area is that last developed, so far as we are now able to determine. It seems, then, that at present the most complex activity of the cortical centers is that concerned in the proper correlation of the individual to his environment. The whole value of all the processes concerned in consciousness is to modify man’s behavior in the midst of the world in which he is placed.
The Right Hemisphere

    The intermediate areas of the right hemisphere and parts of the left hemisphere have not yet become developed, so far as our present knowledge goes. What psychological conclusions may be drawn from the lack of function of these areas we are not now in a position to say. Speculation is easy and safe, since there is no way to demonstrate the falsity of any speculations concerning things which are not known.

Phylogeny of Intelligence
    It is impossible to describe the phylogeny of intellectual attainments in any exact manner, since our accounts of the racial development are extremely imperfect. The first chapters are lost, and we do not even know how many are lost. The paleolithic man had fire, implements of stone, and a certain degree of skill in forming these implements. Cities have been uncovered concerning which the inhabitants of the region have no knowledge, and beneath these, built upon ruins imbedded in the slow drifting of the dust, are found other cities, and others still deeper, and these, even, have shown the use of metals, and the dishes and implements found show much skill and artistic merit in form and workmanship. The Egyptians had attained a high degree of civilization before they built the pyramids, and their scientific attainments were considerable, at least in physics and astronomy. So, in history, the first chapters of intellectual development are lost.
    In the study of the racial development of the human brain one difficulty is met which is perfectly avoidable. Anthropologists measure the skulls of prehistoric peoples with much accuracy from the outside. But these measurements do not indicate the size or shape of the brain with any accuracy at all. If the skulls found could be measured from the inside, or, better, of casts were made of the inside of each skull, our knowledge of the development of the brain during racial progress would be increased. The skulls vary in thickness of the bone and in the size of the various sinuses. These variations are sufficient, in skulls of present peoples, to invalidate any but the most crude conclusions concerning brain development. It may safely be concluded, then, that the same conditions are met in the prehistoric skulls.
Significance of Myths
    In myths and traditions some inkling of the beginning of intellectual development may be found. The truth of the conclusions drawn from the study of myths seems fairly apparent when the myths of distant countries and of races not known to be related are compared. They are found to display very marked resemblances, and these resemblances include the factors which appear to be most significant in explaining, or at least in illustrating, the phylogenetic development in function of the intermediate areas.

    Visual images seem to be considered, for the most part, as commonplace; auditory images are given more attention. The fact that the projection of auditory images upon the cortex followed the projection of the visual images is of interest in this connection. The auditory radiations become medullated at a later time than the optic radiations also. Thus, it is probable that the auditory overflow is of later development, both phylogenetically and ontogenetically, than the visual overflow. Savages dream of sights, but rarely of sounds, and they attribute greater significance to the things heard in dreams than they do to things seen.

    The great significance attached to the naming of things is of interest in this connection. The naming of objects, of ideas, the exact expression of things seen, and thought, and felt in language, is one of the most important factors in education to this day. In myths the relationship is recognized. The monster named was the monster conquered, the fairy named was made to serve, the good quality named was compelled to wait and serve.

    The conquering of evil spirits, or monsters, or powers of malicious intent by means of cunning is another idea which is found among myths. The conquering of good spirits is less often found. In these is found the characteristic of humanity to associate the ideas of the individual with what is good, and to attribute to the forces which impeded him malevolent qualities. The individual is the center of his own universe; the recognition of that fact may be delayed, but the reactions based upon any other supposition meet with disaster. This characteristic of egoism is naively displayed in myths of all races.

United Action
    Myths of somewhat later origin show mankind acting together against a common foe. The very oldest myths show no common humanity, but only individual triumphs. The hero, acting and saving his race or family, appears in the myths not of the most ancient. Thus, the unification of the family and of the race begins before the age of history, but at a later time than the recognition of personal bravery, or cunning in the conquering of personal foes.
No myths, have those of evidently comparatively modern times, portray individuals working together for a common end. Rarely a hero may compel his people, but the single hero is the essential characteristic of these myths.

    Loyalty to ideals is never found; a doglike, habitual sort of fidelity to a person, or obedience to a command, may be found, but rarely.

    Myths are characterized by personifications. The individual is unable to attribute qualities to inanimate objects; he simply fails to see any reason for not recognizing the qualities he sees. If the storm clouds act angry, they are angry. Why not? If the waves glisten like eyes, they are the eyes of a spirit. Why not? If the grain waves like beseeching arms, it is arms beseeching. Why not? Nowadays we see resemblances, and personification is a figure of speech; in myths there is no figure of speech; the things were seen as persons and are so described; the things were heard as speaking, and are so described. The whole saying is naïve and simple, like a child’s tale.
The Ontogeny of Intelligence
    It is true in part that the ontogeny of mental development repeats the phylogeny. The naïve and simple explanation of the various natural events of the days of mythology belong to the childhood of the race. The myths are essentially childlike, though probably they could not be duplicated by the child mind of today; yet the stories told by children now resemble the myths in considerable degree. The explanations of the thunder, the appearance, of the stars at night, the falling of the rain, all these are given by children with the same naïve simplicity, the same ideas of personality and ethics, the same superficial views of cause and effect, that characterize the myths of all races The peculiar stumbling upon truths afterward determined by scientific investigations belong to the childhood of the race, to the young children of today, and to those people of all races sometimes who are included under the class genius. Such stumbling and unbased coincidences are often cited as indicative of some supernatural source of knowledge possessed by children and persons of the genius type; but if the unbased statements made of such persons the world over should be placed in one list, and the facts as later determined to be true should be placed in another, it seems that the laws of coincidence would govern the situation completely. Those who assume the probability of some source of knowledge possessed by children, geniuses and some others use only those occurrences which appear to show the display of this unbased knowledge, but disregard the millions of unverified statements.
    Children and the men of the childhood of the race alike recognized a certain value in dreams. The manner in which this fallacy arises is this: The repetition of occurrences is associated with their recognition as a memory. The occurrences which are not repeated are not remembered. The dreams which are not followed by any occurrences which bring them into consciousness again are forgotten, while the dream which is followed by some occurrence which tends to bring the dream again into consciousness is remembered vividly Thus, the dreams which come true are remembered, while those which fail to come true are forgotten. So it is easy to see why the belief in dreams should be so unfailing a characteristic of myths, of savage peoples and of children. Thus, dreams were held to be expressive of the intentions of some personality beyond waking hours. The forms of clouds and waves, the sounds of wind and falling water, the flying of birds and bees, all natural occurrences which displayed no visible cause, were taken as other expressions of the will and the desires of the unseen. Thus arose the custom of divination in its various forms. This custom also has its place in children’s lives when they act without too exact oversight by pedagogical teacher or parents.

    Such habits of thought are to be considered as the result of the activity of the overflow areas in the absence of very marked function of the intermediate areas. Impulses reaching the primary sense areas were coordinated in the overflow areas; the simplest possible significance was attached to things seen, heard, etc., and the interpretations thus rendered were accepted. The attainment of a really very high scientific and artistic merit is not beyond the possibilities of the activities of the overflow areas. The interpretation of facts is possible to the overflow areas, but the criticism of the interpretation is due to the activities of the intermediate areas.

    The differences between the civilization of the ancient races and the civilization of modern times lies in the action of the intermediate areas. By the activities of the overflow areas abstractions were made and were personified, facts were recognized, conclusions were based upon the facts, but the conclusions were not subjected to any but the most superficial scrutiny. If any interpretation of a fact was offered, it was accepted, apparently, according to the rank of the person who offered it. Even now most of us find it difficult to judge any interpretation of observed facts without reference to the personality of the one who first offered it. It is evidence of the functional activity of the intermediate areas that one is able to view an interpretation of facts, after having verified the facts in the light of evidence, without referring to the personality of the inventory, and without referring to the prejudices or the feelings associated with the subject matter.

    The development of the coordinations in the individual must repeat in part the development of the cortical coordinations of the race.


    It is to be noticed that the evolution of the cortical area has apparently progressed from the posterior toward the anterior part of the hemispheres; or, rather, that the interposition of the anterior and more lately developed centers pushed the earlier centers posteriorly. The olfactory cortex first, then the visual, then the auditory, then the somesthetic areas, all preceded the development of the overflow areas, as the development of the overflows preceded the development of the intermediate areas. The progress of psychical development in any individual probably follows the same path. The commonly-accepted view is that the psychical ideas associated with self are first appreciated, then at a later time the ideas of things distant. It seems very improbable that this is true. The olfactory cortex does not seem to have any overflow area, and the olfactory impulses do not seem to be associated with any reactions apparently conscious for quite a long time. It is true that reflexes may be associated with tastes and smells at a comparatively early time. Visual images are apparently represented first in consciousness, then auditory, then the common sensations. Volitional movements are found latest developed. Reflex actions are present from the day of birth, and these may be associated with sensory stimulation, but these reflexes are not indicative of cortical activities.

Primary Sensations

    The activity of the primary sense areas is associated in consciousness with primary sensations, unassociated with past experiences, uninterpreted in any way, and not localized in relation either to the body itself or to any external condition. Probably this sensation is not to be experienced by any adult human being except under extremely abnormal conditions, and then it would not be possible to recognize the condition, since the very possibility of recognizing the experience necessitates the existence of associational processes.

    The development of the overflow areas depends upon the receipt of impulses from the primary sensory areas. The activity of these areas is associated in consciousness with the recognition of past experiences, the significance of the sensory impulses received, and through the neuron groups relating the sensory overflow areas to one another, the recognition of objects as being perceived by more than one sense. The identity of the thing which is seen with the thing which is heard, or felt, or tasted becomes recognized in consciousness through the activity of these areas. The mentality underlying the age of myths and early childhood depends upon the development of the overflow, but probably not the intermediate areas of the cortex.

    Since the development of the overflow areas depends upon the development of the primary sense areas, and since the development of the intermediate areas depends upon the activity of the overflow areas, it is evident that incoming sensory impulses make the foundation upon which the faculties resulting from the development of the intermediate areas can be built. During the development of the child mind the accumulation of facts is a matter of greatest importance. In the adult, taking up any new line of work, the accumulation of facts is the matter of the first consideration. In caring for those who are sick or who suffer from the psychoses it may be advantageous to develop new relationships among the cortical centers by adding new facts to the memories stored in the cortical neurons.
Upon a basis of observations is built the superstructure of what are commonly called the higher faculties. These observations are most efficient if they include the activities of as many primary sense areas as possible, and if they are related to as many motor impulses as possible.

Educational Principles

    Children should, then, be taught to see things from as many viewpoints as possible, and to interpret the things seen in action and in speech—spoken, written, picture language, and by modeling, if possible. The knowledge of the surrounding country which is gained by walking around over it, by making maps, by looking over the valleys from the hilltops, and by seeing it from the standpoint of the botanist, geologist, historian, artist, farmer, and in the eyes of as many other people as possible, makes the best possible foundation for the development of individual activity in whatever line the child’s characteristics lead him.

The Wider Environment

    In order that a solid foundation of these primary sensory images and memories may be laid, it is best that the environment shall not be too narrow. Probably with a certain amount of guidance a valley among high mountains may serve as a wide enough field for human observation; but this narrow valley is not usually the home of either teachers or parents capable of giving such guidance. The physical outlook should be wide enough to include the possibilities of seeing things from many standpoints, and it should include in its limits enough people of various characteristics and of enough varying outlooks to make the different points of view possible. This increasing of the environment depends very largely upon the manner in which the child’s life is circumscribed by his elders. Children of wealth, traveling with tutors, have probably narrower limits of contact with the world than the mountaineer, who travels at will over his little valley.

Environmental Limitations

    The position of people who are limited in possibilities by limitations of environment becomes extremely pitiable when they become sick, or placed out of the conditions to which they are accustomed. The person whose outlook has been broadened has at his disposal many memories and associative possibilities by means of which he may adapt himself to new conditions; but the narrow mentality, associated with narrow environment, is unable to adapt the individual to new surroundings without much suffering and labor. This is as true of those who do not employ the possibilities of education as it is of those to whom education is denied. The wealthy person whose life processes follow a narrow pathway is as greatly injured, and cramped, and bound in by his habits as is the ignorant, and poverty-stricken, and helpless mountaineer. The child whose every thought and observation have been subjected to the critical scrutiny of his elders is not less limited in his environment than the gamin who lives by his wits in the slums. Both are equally cramped by environmental limitations, both grow into persons of limited possibilities, of narrow outlook, of undeveloped powers.

    It is the duty of every physician to recognize the conditions needful for normal educational factors, and to use whatever influence he has in helping parents and teachers to provide these things for growing childhood. For the narrow grown person the physician can do much also. People have enough powers lying latent to provide for increased possibilities of development through all their lives, and new sensory impulses may be employed in the development of new association processes as long as one lives.

Development of the Intermediate Areas
    The development of the overflow areas is associated with the memories and with simple interpretations. The development of the intermediate area of the parietal lobe brings the possibility of the classification of environmental facts and of the appreciation of external relationships. The later development of the anterior area brings the possibility of coordinating the facts in regard to the place of the individual himself. It is of no use to appeal to the child’s ideas concerning his proper place among other children, or among the other members of his family; as well might one ask a blind man to criticize a painting. The child has no self-brain until about the age of puberty. Then he attains a rather absurd and excessive idea of himself in relation to his fellows; but the development of the neurons of this area in relationship with the development of the neurons of the posterior intermediate area is soon associated with the decrease of the absurdities.
Educational Principles
    In education, the thing to do is to place the child in such a position that the habits are formed which place him right in the world, so far as manners are concerned. If he has the basis of a series of right habits, the conservatism of habit will secure him a good place to start from in his determination of his own place in the midst of things. He should start out with the habits of manner, and thinking, and use of himself which are customary among the people among whom he lives, then whatever further place he has will depend upon his individual reaction to his individual environment.

    Education begins with the beginning of life. The transmission of nerve impulses from one nerve cell to another causes a lowering of the liminal value of the nerve cells concerned. The transmission of nerve impulses through any neuron series lowers the liminal value of that series. The performance of any reaction causes that reaction to be more easily performed at a later time. Every time any reaction occurs, that reaction becomes easier. Upon this physiological fact depends all of education. This is the reason for repetition in education. The liminal values of the neurons concerned is lowered until the reaction repeated becomes habitual. The teaching of little children can include practically nothing but the formation of right habits.

    The development of the habit of obedience is one which many parents insist upon. Doubtless many parents develop this virtue too greatly in their children, since too implicit obedience may lead to personal weakness in later years. But a sensible obedience is a thing which is natural to most children, unless they are spoiled by being constantly commanded to do unpleasant things. To teach obedience is usually unnecessary, for it is natural for a child to obey without question, under ordinary circumstances. The child who has become disobedient is not usually well trained to obedience by harshness. One of the best ways to deal with such children is that through repetition. He is told to do the thing which he would do anyway, but he is not compelled to do that which he dislikes. When everything he wishes to do is preceded by authoritative direction, he finds himself unable to do that which he wishes without obeying. The habit of obedience is soon secured; then rather gradually a certain amount of initiative may be permitted, and he may be told to do things which he might not find agreeable. If he obeys, well and good; if he does not obey, the dose must be repeated; he must be told to do everything which he wishes to do, without exception, until the habit of obedience is established again.
Excessive Subordination

    A fault of earlier times, which does not exist to so great an extent nowadays, is the habit of maintaining parental subjection for too long a time. In olden times children whose intermediate areas were becoming developed were kept in the most implicit subordination. The impulses aroused by environmental changes were transmitted into motor impulses, not as the result of the activities of the child’s own brain, but as he interpreted the probable decisions of his elders. During the last century it was not rare for the children of the most worthy parents, children of the most admirable training according to the opinions of the times, to grow into the most wicked reprobates. The maintenance of too great subjection after the intermediate areas begin to become developed is associated with the presence of antagonistic series of impulses due to the activities of these areas. The ultimate reaction is, for a time, that due to the predominant influence of the parental teachings, but with these are associated the antagonistic effects of the impulses concerned in the appreciation of the youth’s own thought. The reactions chosen are thus permitted to act upon the motor overflow areas; the liminal value of the neuron systems concerned in the reactions exactly antagonistic to all his teachings is lowered day by day, until finally the time comes when he is apt to find the neuron systems concerned in the expression of his own opinions and desires more efficient than the steadily-weakening influence of the teachings of his childhood, and he is apt to follow every impulse against which his early teaching was directed.

    The pendulum has swung too far in the other direction now, in some families. The children are thrown upon their own responsibility before the overflow or intermediate areas are capable of performing any duties of association or coordination. A number of avoidable errors is thus made a regrettable part of the child’s experience.

Development of Character

    The rational method is that indicated by the physiological development of the cortical areas. The child should not lose his tendency to obedience; if this does occur through wrong training, he should again be accustomed to the habit. This is done, as is given in another section, by telling him to do everything which he wishes to do, without exception. Let him not be able to find anything which he wishes to do, which he has not already been told to do. The habit of obedience is bound to follow, and this without any of the furious storms which usually are associated with the endeavor to compel an unwilling obedience in an obstinate, spoiled child. Such storms are harmful beyond measure, and usually the child is the real victor in the contest.

    Obedience should be absolute during the earlier years. With the beginning of evidences of reasoning, the endeavor should be made to let him use this power gradually, and, without his recognizing the fact, let him do practically the same things he has been doing obediently from the effects of the activities of his own brain. The environmental changes thus initiate appropriate reactions directly, the liminal value of the neurons concerned in rational and well-chosen reactions become progressively lower, and the rational actions become fixed in the physiological condition of the cortical neurons—that is, become an integral part of his character. No antagonistic impulses are thus permitted to affect the motor overflow, since he has been led to choose the rational reaction himself, and no inhibitory neuron systems enter into the situation at all.

    Obstinacy in children and in older people is the condition associated with the overactivity of the neurons of inhibition. It is probable that the inverted pyramids of Martinotti are the neurons most concerned in this reaction. Increased stimulation of the neuron series concerned stimulates the inhibitory cells all the more. The endeavor to cause obedience in the obstinate child or to limit certain crimes among grown people by the use of excessive punishments is productive of harin. The attempt should be made to secure the reaction desired without the intermediation of the inhibitory neurons. This is done by giving instruction to children while their muscles are relaxed, as after they are in bed at night sleepy and tired, or at any time when they are found to be “biddable” and well. No attempt at discipline or instruction should ever be made when a child is sick, or overtired, or hungry.

Development of Personality

    After puberty, when the anterior intermediate areas have become developed, the personality of the individual becomes fairly well fixed. The activities of the various intermediate areas relate his activities to the conditions of his environment and to the activities of his fellowman. The activities of the overflow areas constantly bring memories of the past events of his own life to be associated with present sensory impulses; the overflow areas also interpret the things perceived by present experiences. The activities of the intermediate areas interpret, and criticize, and modify, and control the reactions coordinated by the ganglionar centers. Deciding the propriety of any emotional reaction, he permits that emotional reaction full play, as previously decided upon. Thus life has in its emotional characteristics the force associated with the reactions controlled by the basic instinct and emotional states, but has none of the destructiveness due to the unbalanced activities of the ganglionar centers

    Any discussion as to the possibility of the inheritance of acquired characteristics is beyond the purpose of this paragraph. It is enough to say that the facts seem to indicate either the possibility of acquired racial characteristics, or that the forces of variations, survivals, deaths and choice act in practically the same manner in the perpetuation of certain characteristics of cerebral development. Since the inheritance of visible structural characteristics is practically proved beyond question, it may probably be granted that there is an inheritance of those structures which are not visible.

    The inheritance of the structural relationships which underlie the functional relationships of the neurons is quite as much a certainty as is the inheritance of a certain form of lip or of chin, or of any other feature. The inheritance of the neuron groupings which underlie the consciousness of certain facts is thus assured. The inheritance of certain paths through the central nervous system, by means of which certain environmental changes are easily and quickly followed by certain motor reactions, is also a matter which may be granted This inheritance is brought about, no doubt, by the same evolutionary forces, whatever they may be, which have produced the present development of the other parts of the body.

Affectional Reactions

    When it occurs that any sensory impulses arouse an immediate motor reaction which includes both visceral and somatic structures, a sense of emotional states arises in consciousness. This is due to the persistence of the primitive racial characteristics. Whenever any given association process is concerned in the coordination of certain facts, as of axioms, or of what are called “higher” truths, the neuron systems concerned are those whose liminal value is the lower because of the racial experiences. Thus it is found that such truths are greeted in consciousness with a sense of acquaintance, of pleasure or distaste.

General Statements

    In the progress of human development it has long been noticed that the study of the most distant objects, the stars, was the first scientific attainment of the race. This is true, to a certain extent, of all races. Many of the savage races are exceptions to the rule. Later the studies included subjects nearer at hand.
In artistic history it is found that the development of painting and sculpture preceded the development of music.

    In dreams, especially among savages, the auditory images are much less distinct than are visual images. Myths show a constant tendency to attribute to auditory hallucinations a mystic force, while visual hallucinations usually are dismissed as dreams.

    All of these facts are probably due to the fact that the auditory overflow becomes developed at a later time than the visual.

Developmental Precedence

    In the processes of the development of the cortical coordinations the functions of the overflow and intermediate areas follow a long way after the development of the primary areas. The progress of the race in civilization is indicative of the comparative slowness with which the attainment of anything like perfect functioning of the intermediate areas occurs. The steps in the development of the overflows follow in the order of the development of the primary areas with which they are associated and the development of the intermediate areas follows the same steps also. Since the overflow areas for the olfactory and gustatory impulses are not recognized, it is evident that we can not determine whether the same laws are concerned in these sense as in the others or not. Of the senses whose relationships are known, at least in part, the laws a given seem to be true.

Phylogeny of Visual Coordinations

    The visual area is developed first, and the visual overflow is concerned in the coordination of the visual images before the auditory areas are developed in anything like the same degree. This is shown in many ways; the characteristics of the older myths, the development of the visual ideas in the child, the comparative development of the visual functions in feeble-minded children, the facts of the phylogenetic development of the cortex, all show the greater age of the cortical projection of visual images.

Phylogeny of the Auditory Coordinations

    The auditory impulses follow the visual, and the development of the primary motor area of the cortex appears to become efficient at about the same time. The auditory overflow area is continuous with the visual overflow area, and the development of the area intermediate between the two is completed at a somewhat later time. The comparative youth of the auditory projection upon the cortex is associated with the facts of mythology, of the development of painting, sculpture, or architecture, all of which depend upon the visual cortex. In the average child, also, the sense of music is developed at a later time than is the sense of color or form.
The significance of things heard is developed at an earlier time than the significance of things felt, or of things as resistant to muscular effort.

Phylogeny of the Somesthetic Coordinations
    The projection upon the cortex of the common body sensation is a matter of later development. Among savage races and among those people who have neither the time nor the energy to attend to any but the merest necessities of life, the physical senses are of great importance in modifying the daily reactions, but not in adding to conscious knowledge in great degree. This condition, present now among the very poor and among savages who live with much difficulty, is associated with no particular attention to the body sensations, except as pain impulses compel a certain degree of attention. There is some reason to believe that these people do not suffer so great pain under the exigencies of life as people of higher nervous development do. This may be, perhaps, due to the fact that individuals who do suffer die off rather early in life among those people, while only those who feel comparatively little pain endure existence for a certain time. Among civilized people, on the other hand, every effort is made to perpetuate the physically unfit.

    The beginning of the development of the common sensory overflows and of the neighboring intermediate areas seems to be associated, first, with a tendency to the exaggeration of these sensations, and then with a tendency to their limitation in consciousness.

Bodily Injuries
    Thus, among savages of all races and among the primitive people there is found the care of the body which almost amounts to worship. This tendency is associated, later, with the decoration of the body in ways which add to the sensory stimulation and to the high esteem in which the body itself is held. The process of tattooing illustrates this condition. The painful process occupies many weeks, perhaps many months and years, and yet it is done with much pleasure. The wearing of earrings and nose rings, the slitting of the lips and cheeks for the sake of wearing jewelry and various decorations, the mutilation of sensitive parts of the body, with associated decorations or without these, all indicate the low pain threshold and the reactions characteristic of the cortex in which the common sensory areas were being developed.

    Later the common sensations became sufficiently developed to fail to arouse any of these incoordinated and injurious reactions. During the developmental period of any area the attainment of function is first associated with the performance of exaggerated function, then occurs the period of lessened function with increased association impulses, then the times of completed associations, with the associated consciousness of the sensory images and the employment of these sensations in the control of the daily life processes. In the development of the cortical areas for the common sensations the period of comparative inactivity is associated with a tendency to “mortify the flesh.” The people of the middle ages did this, and to this day the association of extreme goodness with bodily pain is present in the minds of most people.

    That great merit is to be attained by suffering alone is one of the ideas of the primitive mind, and it depends upon the developmental processes as they occur in ontogenetic as well as phylogenetic development.

Ontogeny of Sensory Coordinations
    Children pass first through a naïve and childish stage of bodily vanity, in which, with no apparent self-consciousness, they decorate themselves with bits of bright ribbon and feathers in a savage and outlandish manner. This is usually followed, in most children, by a period of self-depreciation and especially of bodily inattention. The repugnance to the bath of this period is as pronounced as in the days of the early martyrs. Probably something of the same reason lies at the base of both peculiarities.

    Later the fuller development of the common sensory overflows and the associated development of the anterior intermediate area is associated with the beginning of the extremely egotistical stage of consciousness. The body is then again a thing to be cherished and cared for, this time in the light of the most intense self-consciousness. This stage occurs at about the age of puberty, and the egotism of that period is due to the development of the anterior association areas, together with the initiation in the lower centers of those sensory impulses associated with the increased function of the sexual organs and the circulatory changes associated with this increased development.

    With the attainment of the adult life the normal individual undergoes the changes in his sense of personality which are necessarily associated with the development of the coordination of impulses from other parts of the cortex with the anterior association areas. Also, the changes in neuronic function initiated by varying environmental conditions cause the activities of the anterior association areas to become modified in accordance with the greater range of associational impulses; thus the reactions become saner and the consciousness of personality assumes something like a rational development.

Present View of Sensory Impulses

    At the present time, among the more highly-educated and civilized peoples, the care of the body assumes a fairly just importance in the conduct of life. The body, as a sort of complex machine, able to attend to the duties laid upon it by the activities of the cortical neurons, is beginning to be recognized as a thing to be cared for and saved, or to be mistreated and destroyed. The older ideas of diseases as entities, or as punishments sent for some strange purpose, are superseded by the newer thought, that the laws of cause and effect are as immutable inside the body as outside the body, and that the abuses of the body must be followed ultimately by a loss of usefulness.

    It is true that the body is still valued, by some races and by some individuals of all races, as if its chief worth lay in its lack of usefulness and in the value of the things which can be attached to it. There are other races and other individuals among all races who still hold to the older ideas that the body is a thing to be disregarded and kept subject to the so-called “higher” faculties, or to be considered as non-existent. The best thought today is that which sees in the body a thing whose chief value lies in its efficiency, the strength of its muscles, the keenness of its vision, the range of its environment and the perfect coordination of the cortical neurons, upon which depend the wisdom and efficiency of the daily answers to the daily demands of living.