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A PHYSIOLOGICAL BASIS FOR
EDUCATION has hitherto for the most part been treated as having no physiological basis, and only an empiric psychology; the time seems to have arrived when an attempt should be made to bring it into line with other arts, since unscientific methods mean waste of material and energy, and the material wasted is that of which the nation should be built. As the development of the muscles and other organs of our bodies depends on the kind of physical culture they receive, so also does the development of our psychical or mental powers depend on the systematic training, or education, which the living substance of our brains receives. Included in this living matter there are elements whose function it is to receive and to become impressed by energy derived from the outer world and from the movements of our limbs and bodies; these impressions are reproduced when these charged elements are re-excited by appropriate stimuli. Action of this kind is well known and is included in the term Memory. In addition to these mnemic elements the human brain contains a large mass of living matter whose function it is to transform the energy derived from our sensations and ideas into psychical force, that is, into thoughts and into intellectual processes which act on certain motor cerebral centres and become manifest in the movements of our limbs, or, it may be, in silent or articulate language. Lastly, the function of other parts of the human brain-substance is to elaborate those hereditary instinctive and primitive emotional tones of feeling which, to a large extent, form our personal character and that of the race or society to which we belong.1
The Psychology of Education, by J. Welton, M.A., Professor of Educa tion in the University of Leeds, pp. 7, 40, 70. Throughout the following pages the term personal character is employed to signify those hereditary instinctive and emotional processes which, it is conceived, form the substratum of our actions, and to a large extent rule our whole life. (See International Scientific Series, vol. xcvii. p. 2.) These primitive emotions include among others anger, hate, fear, joy, sorrow, disgust, etc. To these instinctive hereditary processes Mr. Edmond G. A. Holmes would add from his experience of child-life the following-communicative, dramatic, artistic, aesthetic, inquisitive, and constructive instincts. What is and what might be, by Edmond G. A. Holmes, late Chief Inspector of Elementary Schools, pp. 165-188.
Our subject may be treated in two sections: in the first place, the explanation of the nature and the development of that form of living matter the orderly working of which is necessary for the manifestation of our instinctive and emotional faculties; and the consideration how far this kind of matter can be influenced by education. We shall then proceed to show that thoughts and reasoning powers result from work performed by elements of our central nervous system, whose development depends on the culture they receive, especially during childhood.
In the first place, however, it is necessary to refer to memory, without which neither mental nor emotional tones of feeling could have come into operation; it is not confined to elements of the nervous system, but appears to be common to all forms of living matter-in fact, to constitute one of its fundamental properties.
Professor F. Darwin, when referring to the nature of the memory-like character of movements made by the leaves of sleeping plants, states that if plants of this kind are placed in a dark room after they have gone to sleep at night they will be found next day in the diurnal position, and they again assume the nocturnal position as evening comes on." These plants normally drop their leaves at the stimulus of darkness, and raise them at the stimulus of light. But here, as we see the leaves rising and falling in the absence of the accustomed stimulation, these movements must result from the internal 'physiological' conditions which habitually accompany them.
The possession of memory is indicated by the fact that the result of the stimulation of light on the living substance of the leaves of these plants was not momentary in its effect, but left a trace of its action which regulated the subsequent movement of the leaves; not only does the living matter of these plants retain impressions it has received from former stimuli, but it is in consequence of the action of these impressions that its subsequent movements are effected.
The movements of many of the simplest forms of animal and vegetable beings indicate the possession of memory. An amoeba, for instance, consists of a minute particle of protoplasm, which has been seen to seize a smaller amoeba: the latter escaped from its grasp, but was pursued and re-captured. In Professor Jenning's opinion, these movements of the amoeba indicate a power on the part of its living substance to act on former experience, or by the aid of its memory. Another of these unicellular beings, known as the stentor, possesses vibrating hair-like processes which encircle the opening leading into its body cavity; these processes move in such a way as to direct 2 Presidential Address of the British Association for the year 1908.
particles of food floating in the surrounding water into the stentor's body-cavity, or, by a reversed movement, to push objectionable materials away from this opening. This power of choice involves the use of memory, a fact which is confirmed by an experiment made by Professor Jennings on a stentor, in which he subjected this being to the influence of a stream of water containing grains of carmine. The stentor did not at first react, or move away from the stimulus or impact on its body-substance of the carmine particles; but after a time it bent its body first to one and then to the other side, as if to avoid the shock caused by the grains of carmine. After this mode of treatment had been repeated several times, the stentor at once responded to the stimulus, reversing its ciliary movement, and finally contracting into its tube. The important thing to note is, that after several repetitions of the above treatment, the stentor 'contracted directly the stream of carmine came in contact with its body.' We refer such a movement as this, in the case of the higher animals, to the result of memory, association, habit, and learning.'
Mnemic and purposive elements appear to be distributed throughout the living substance of the bodies of unicellular organisms; in the lowest class of multicellular beings we find that these elements have separated into structures, each of which possesses the power to do a particular thing, and to work in a particular way. This separation of living elements into definite forms appears to result from the action of the environment. Thus we conceive that the mode of energy we call light, by its action on those elements of living substance which possess a special aptitude for receiving such stimuli, has gradually produced coloured structures such as those known as eye-spots, which are common in unicellular beings; from these simple structures the complex eyes of the higher animals have gradually been evolved. In the same way energy derived from contact or touch has in the course of time effected molecular changes in certain of the living elements of the simplest form of multicellular beings, and has moulded these elements into 'receptors' of this mode of energy, or into tactile sense-organs with their system of nerve cells and fibres. For example, a network of nervecells and fibres exists in polyps beneath their outer or skin layer of cells. These nerve-cells consist of small nucleated masses of protoplasm from which fibres extend in all directions, like wires from a central telegraph station. There are on the surface of the polyp's body upstanding protoplasmic processes adapted to receive the impact of energy from the outer world, and to conduct such stimuli to the mnemic and purposive 3 International Scientific Series, vol. xcv. pp. 108, 113.
elements of a subjacent nerve-cell, thus setting free some of its working energy, which becomes manifest in the movement of a contractile muscle-cell or fibre under the control of this particular form of energy. A structural arrangement of this kind constitutes the simplest form of what is called a tactile senseorgan, with its corresponding nervous and muscular system. By a sense-organ, therefore, we mean an arrangement of elements adapted to receive, sift, and transmit energy derived from various sources to corresponding nerve-cells; this energy is transmuted into nerve-force by the constituent elements of the nerve-cell, and is conducted to muscular structures, producing definite movements of the animal's body. These movements are, as a rule, purposive, that is, they tend to promote the well-being of the organism. The brain of higher animals, including human beings so far as our subject is concerned, consists of a vastly complex arrangement of nerve-cells and fibres. The living substance of these cells consists of elements adapted by their molecular arrangement and motion to transform physical forms of energy into specific modes of nerve-force, which becomes manifest in mnemic, purposive, psychical, motor, or other kinds of work. The whole of these cells are brought into relation with one another by means of their communicating fibres. Energy discharged by the living matter of a nerve-cell passes along those nerve-fibres which, from constant use, have become highly tuned as conductors of that special form of energy which controls the action of certain groups of muscles, and thus causes the movements of the body and limbs of the animal.
Experiments on ants demonstrate that the action of the instinctive and emotional elements of insects depends on energy they receive through means of the sense-organs acting on their brain. M. Forrel has proved that the olfactory-sense-organs of these insects are located in their antennæ, and that it is through these organs that the ants' instinctive actions and emotional feelings are brought into play. If an ant's body is smeared over with fluid pressed from the bodies of its companions and the insect is then returned to its nest, its companions take no notice of the stained ant. But if an ant is smeared with fluid pressed from the body of ants of a hostile species, and is then returned to its nest, its companions immediately attack and kill it. Different genera of ants, which under ordinary conditions are deadly enemies, live together on friendly terms after having their olfactory organs removed; having no olfactory-sense-organs they fail to distinguish friend from foe; the mnemic, instinctive, and emotional elements exist in the nervous matter of their brain,
The Evolution and Functions of Living Purposive Matter, by N. C. Macnamara, pp. 60, 67, 68.
but can no longer be brought into play, because the natural source of their excitation has been destroyed. From these senseorgans nerve-fibres extend to sensori-motor nerve-cells, located in what is known as the insect's mid-brain; this corresponds to the portion of the brain of vertebrates hereinafter called the cerebral basal system or primitive brain. It is, we contend, the function of this part of the brain to elaborate the hereditary instinctive and emotional processes displayed by all orders of animals, and out of this matter the psychical areas of the human cerebrum have been evolved.
In the three lower classes (fishes, amphibians and reptiles) of the five into which vertebrate animals have been divided, the central nervous system may roughly be said to consist of a rod-shaped mass of nerve-cells and fibres known as the spinal cord, which, when it passes into the skull, expands so as to form the lower brain, and is continued into the mid- and inter-brain, which, with their associated lobes, form the primitive brain or basal nervous system. The brains of these three lower classes of vertebrates have no true cerebral hemispheres: that is, they do not contain nervous structures similar to those which in the higher orders of beings elaborate psychical processes. Consequently the nervous energy causing the hereditary instinctive and emotional movements of these beings is derived from their basal nervous systems, lower brain, and spinal cord. The movements of fishes, amphibians, and reptiles therefore, like those of insects, result from reflex or from automatic processes: that is, they are effected independently of psychical or mental nervous energy. Nevertheless, the animals included in these three classes possess retentive memories, and show by their actions not only instinct but also emotional feelings. For instance, Mr. Pennell states that, in company with the superintendent of the Zoological Gardens, he visited the building in which the glass tanks containing perch were located. The keeper of these fish was also present, and so long as he moved about in front of the tank the fish took no notice of him, but when he walked from the tank towards the cupboard where he kept the net used for introducing food into the tank, the perch swam rapidly across their tank with their fins erect, evidently in a state of high emotional excitement. The instinctive actions and emotional feelings of fish are still more conspicuous in the way sticklebacks build their nests and guard their young from injury. That these mnemic, instinctive, and emotional characters are hereditary qualities in fish and the two other classes of animals we have referred to, is shown by the fact that they are passed on by germcells from one to succeeding generations of the same order of beings inhabiting all parts of the world.
VOL. LXXI-No. 423