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A PRELIMINARY CRITIQUE OF THE DOCTRINE OF FUNDAMENTAL AND ACCESSORY MOVEMENTS.
By EVERETT SHEPARDSON, Supervisor of Training School, Los Angeles State Normal School.
We hear much nowadays (2, 3, 32, 23, 30) in criticism of practices in our schools that involve the early use and too great use of the finer muscles, and the neglect to provide for the corresponding action of the larger muscles of the body. My own tendencies of thought were quite definite along this line. But when I attempted to give reasons for my belief that would stand the test of scientific criticism I could not give such reasons. This study was attempted with the hope of finding definite evidence and material for a constructive criticism of our curricula, methods, and administration with reference to the development of fundamental and accessory muscles. It is only fair to state at the outset that as this paper begins with questions, so it closes with questions; and so becomes not a thesis but a study preparatory to later ones.
It is not hoped to make any contribution to the science of education, but rather to make more definite the limits of knowledge (or of ignorance) so as to set off some of the things that are known from what is believed. The writer's motive is fourfold. I. That such opinions as we school people should hold might be more satisfactorily formed, based upon what is known, with a consequent result of greater faith in such opinions.
That we might regard certain other opinions as of a decidedly tentative nature and be on the lookout for evidence that bears upon the questions involved.
3. That certain gaps in knowledge might be located for investigation, or at least, noted so that we might be on the lookout for new material.
4. That we might have, to a greater degree than at present, the questioning attitude toward all of our schoolroom ideals and practices.
The terms Fundamental and Accessory, in the somewhat definite sense in which they are now used conjointly, were, so far as I have found out, first used by Ross (2, p. 15) at least as early as the early eighties and applied to parts of the nervous system. It is very evident that any consideration of the development of fundamental and accessory muscles must almost
necessarily take account of corresponding development of fundamental and accessory nervous structure, since movement is but a function of which the co-ordinating nervous parts are a portion of the structure, and structure and function, from the evolutionary point of view, are correlative.
"The portions of the nervous system which man possesses in common with the lower animals and which are well developed in the human embryo at nine months," Ross (8, p. 69, and 8a, p. 84) calls "the fundamental part; and the portions which have been superadded in the course of evolution, which differentiate the nervous system of man from that of the highest of the lowest animals, and that are either absent in the human embryo, or exist only in an embryonic condition," he calls "the accessory part of the nervous system."
He says (8, pp. 68-69, and 8a, pp. 83-84): "The main movements which distinguish man from the lower animals are those concerned in attaining and maintaining the erect posture, the varied movements of the hands as organs of prehension, the movements of voice and articulation concerned in speech and those which are active in the production of facial expression. All these movements must, therefore, be represented in the human nervous system by structural arrangements superadded to those which man possesses in common with the highest of the lower animals. Indeed all the complex movements first mentioned are acquired considerably after birth of the human infant, and we may consequently expect that the structural arrangements corresponding to them either do not exist at birth or exist only in an embryonic condition."
Such expectation has been realized. "Die Functionsfähigkeit einer Nervenleitung, ihre Fähigkeit Reize fortzuleiten an das Vorhandensein einer isolirenden Markhülle gebunden ist." (17, p. 227.) The investigations of Flechsig et al. (2, pp. 11, et seq. and 3, p. 234) have shown that the fibres connected with the centres that control reflexly the fundamental movements are medullated before birth, while fibres connected with the higher centres are not so medullated.
G. Stanley Hall (5, p. 154; cf. 19, p. 510) classes as accessory the movements "of the hand, tongue, face, and articulatory organs," thus agreeing with Ross except that Hall does not include the movements that have to do with erect posture. As a schoolroom problem we might, of course, eliminate from our consideration this non-included group, since the children when they come to us have already attained the erect posture, although, as we too sadly notice, at times they do not maintain it with sufficient exactness.
But why, when they are listing the accessory movements, do these leaders omit the fine muscular adjustments that come
with active attention? To me they seem as distinctively human as do the movements of the hands or of the larynx. One of the conditions that modern psychology has emphasized as a requisite for active attention is the muscular-tension-preparedness (44, 47). There is no indisputable evidence that animals, or children before they actively attend, have the muscular strains that you and I feel in the fine muscles used in attention, often especially in the scalp-particularly in the parts of the scalp covering the forehead and the occiput (7, p. 386, and 24, p. 374). Many of these muscles, it is true, are facial muscles, but some of them are not-in fact the same kind of tension is felt, although usually to a lesser degree, in various parts of the body. After all, it is not the differences in the muscular anatomy per se that are really distinctive, it is the differences in function; and it might be better to speak of fundamental and accessory movements than of fundamental and accessory muscles.
Those that emphasize the theory of the order of development of movements from fundamental to accessory, point as a confirmation of their theory to the fact that in the degeneration that comes either through old age or through gradually increasing general paralysis of the body there is a loss first of the most completely accessory movements-those controlled by the highest centres-toward the less accessory and the more and the most fundamental. The genetic and pathological loss of control should be paralleled in the loss of control due to temporary fatigue. In the schoolroom one of the first evidences of fatigue is the wandering attention of the pupils. Dissipation of active attention can arise only when the muscular tensions correlative to mental concentration are absent. Should not the muscular movements accompanying active attention be classed in the accessory movements for our purpose? It seems to me that they should be so classed and I shall so consider them.
If nerve and muscle structures corresponding to higher functions were merely superadded as children develop, our problem would be much simpler than it is. But these accessory movements do not replace fundamental ones. They always include certain fundamental movements, sometimes with marvellously wonderful combinations of fundamentals and less complex accessories.
Dr. Hughlings Jackson (1, 8), in 1872 (or earlier) presented a theory of control of the muscles that simplifies the problem for our consideration. His theory is most often spoken of as the Hughlings Jackson Three-Level Theory of the Nervous System. The nerve centres of the lowest level are those of the spinal cord, medulla and pons, so that the movements on this lowest level would be such 'vital' movements as those that are
involved in the circulation of the blood, respiration, crying, sneezing, coughing, sucking, digestion, excretion, and the grasping acts of infants. For all these the sensori-motor apparatus is perfectly organized before birth and the sensori-motor action is typically automatic.
He included in the centres of the middle level the basal ganglia of the brain, together with the 'sensori' centres of sight, hearing, and the other 'special sense' ganglia, with the convolutions that are in immediate relations to them. These centres receive impulses not directly from the periphery, but through the ganglia of the lowest level, and the movements controlled by these centres would be controlled through the centres of the lowest level. Such movements would be produced as might be exemplified by the grasping of a thing seen, the removal of an offensively smelling object, or other like movements such as any of the higher animals, some imbeciles and rather young, normal children might perform without much thought.
Jackson's investigations were carried on in the laboratory of clinical practice, especially in connection with cases of epilepsy. He realized that his classification was in some degree unsatisfactory and he pointed out some of its shortcomings, but these two lowest levels of control were fairly well established and upon the basis of the theory nearly every phenomenon involving these kinds of control could be explained.
He went farther, however, and claimed, hypothetically, that the remaining portion of the brain comprised the highest level.
As the lowest level sensori-motor centres "represented" external stimuli in both the reception of stimulation and the motor response, and as the centres of the middle level, being also sensori-motor, "re-represented" the external world by mediation of the lowest centres and fibres, so the other centres in the cerebrum must be also sensori-motor and must, through the mediation of the two lower levels, "re-re-represent' the external world. Thus, according to Jackson's theory, every muscle of the body is represented in each of the different levels of the nervous system both as to sensory stimulation and motor control (cf. 7, p. 394).
It may be of interest to note that Flechsig, attacking the problem in quite a different manner, found what might be considered corroboration of Jackson's theory concerning the control of these highest centres over the lower, in that he found that the highest centres connected with both the sensory periphery and the muscular mechanism not directly but through the next lower centres. And immediately he stated (in 1896) practically the same hypothesis for the portion of the cerebrum not included in Jackson's middle level.
FUNDAMENTAL AND ACCESSORY MOVEMENTS.
He says (13, pp. 22-23): "Nur etwa ein Drittheil der menschlichen Grosshirnrinde steht in direkter Verbindung mit den Leitungen, welche Sinneseindrücke zum Bewusstsein bringen und Bewegungsmechanismen, Muskeln anregen; zwei Drittel haben direct hiermit nichts zu schaffen; sie haben eine andere, eine höhere Bedeutung." And again, "Die (13, p. 24) geistigen Centren sind also Apparate, welche die Thätigkeit mehrerer innerer (und somit auch äusserer) Sinnesorgane zusammenfassen zu höheren Einheiten. Sie sind Centren der Association von Sinnes-Eindrücken verschiedener Qualität, von Gesichts-, Gehörs-, Tasteindrücken, etc.; und sie erscheinen insofern auch als Träger einer 'Coagitation,' wie die lateinische Sprache prophetisch das Denken bezeichnet hat, sie können also specieller auch Associations-oder Coagitations-Centren heissen." (See also 12, p. 112; 3, p. 176; 51.)
We should note that Jackson's theory would require that each and every part of the central nervous system should be at the same time sensory and motor. This would require that the 'motor' area in the brain should have sensory cell-elements and that the 'highest' centres should have motor elements. Modern anatomical and physiological investigations have shown that such an hypothesis is probably the expression of the truth (7, 12, 3).
The main features of the Jacksonian hypothesis have stood the tests to which they have been put. If we note especially that control (3, pp. 263-264) is exercised by each level over each part of the body, and its implication that each level is both sensory and motor, it seems to me that we might make a more helpful use of the terms fundamental and accessory, if, when we use the terms, we put more of the idea of control into their connotation. We should not then contrast so much the fundamental muscles with the accessories, central muscles with peripheral muscles, nor large muscles with small ones, nor large movements with small movements, nor few muscles with many muscles-all of which contrasts have been made by writers on the subject. Nor should we lay ourselves open to the criticism that Thorndike gives when he calls attention to the fact that one of the first movements that the child is capable of making after birth brings into play the fine movements of the fingers (36, p. 105, and 37, p. 76).
The child at birth has muscles strong enough to grasp a small rod and support its own weight for several seconds, but it has no voluntary control over such movements (20, p. 838). In fact it usually loses this power after a few days, and any one who remembers the difficulty he had in learning to hold his own weight upon the horizontal bar will realize how, had he known of his earlier powers, he might well have sighed for a retention of this remarkable Simian characteristic. Had there been care to think and speak of accessory movements in the sense of movements controlled by higher centres rather than to