Sense organ

“ The Adaptation of the Sense-organ.—This occurs not only in sensorial but also in intellectual attention to an object.
That it is present when we attend to sensible things is obvious. When we look or listen we accommodate our eyes and ears involuntarily, and we turn our head and body as well; when we taste or smell we adjust the tongue, lips, and respiration to the object; in feeling a surface we move the palpatory organ in a suitable way ”

“ The arrows pointing away from perception and emotion are intended to indicate the fact that the consciousness of sense-stimulus on the one hand, and of activity on the other hand, are accompaniments of the nervous processes in the brain, and are referred outwards to the sense-organ or the motor-organ, as the case may be. ”

“ The organs of sense sending their judgments by the sensory nerves from the exterior, the organ of feeling from the interior, and we are compelled to infer that every particle of matter in the animate body has judgment; and that in the organs of sense they have judgments of cognition, but in the mechanical organs they have judgments of good and evil. ”

“ Finally, though the figures of bodies are in truth resembled by the figure of the part of the organ of touch, which is stimulated into motion; and that organ resembles the solid body, which stimulates it, in its property of solidity; and though the sense of hearing resembles the vibrations of external bodies in its capability of being stimulated into motion by those vibrations; and though our other organs of sense resemble the bodies, that stimulate them, in their capability of being stimulated by them ”

“ By means of the nerves all impressions are conveyed to the brain and spinal cord; all impulses from this, whether conscious or unconscious, are conveyed to the muscles and other parts. The brain is the sole organ of psychical life; by means of its activity the impressions of the external world conveyed to it through the sense organs are converted into consciousness. ”

“ Hence the whole muscular system may be considered as one organ of sense, and the various attitudes of the body, as ideas belonging to this organ, of many of which we are hourly conscious, while many others, like the irritative ideas of the other senses, are performed without our attention. ”

“ The physiology of a sense, consists in an external organ,—as the eye or ear, its nerves of sensation which spread through the brain, and, the nervous fluid. To each of the senses there belongs a distinct cerebral organ, which, if deducted, leaves nothing to constitute the physiology, but the exter [Pg 18] nal organ, the nerves, and nervous fluid; such may be considered the physiology of all the senses, so far as the exciting mental perception is concerned. ”

“ An organ, swayed by slight impressions is an organ whose natural state is one of unstable equilibrium. We may imagine the various lines of discharge in the cerebrum to be almost on a par in point of permeability—what discharge a given small impression will produce may be called accidental, in the sense in which we say it is a matter of accident whether a rain-drop falling on a mountain ridge descend the eastern or the western slope. ”

“ The organs of sight and hearing are now by far the most important of our sense organs. They enable us to sense things that are at a distance. We shall therefore discuss defects of these two organs only. ”

“ The same may be said of the nervous system as a whole, whose function it is to translate into action the stimuli received through the sense-organs, whether directly or by means of intervening nerve-cells, which form central organs of ever-increasing complexity of composition. ”

“ Therefore, in order that a true perception may be experienced, an organ of sense, a nerve, and a mass of gray nerve-tissue are necessary, and no other organs are required.
It is rarely the case that an individual perceives an impression made upon any one of the organs of the senses without a higher mental operation being performed. ”

“ The physiology of the senses and sense-organs of animals is studied as preliminary to the psychical or mental accompaniments of affections of those organs, which are styled explosive disturbances in the brain or other aggregated mass of nerve-cells. ”

“ The brain, then, and the various nerves of sense in continuity with it, may, when taken together, be considered as forming one great organ, which I would term briefly the sensorial organ, essential to life, and to the immediate production of those mental phenomena which constitute our sensations, and, perhaps, too, modifying in some measure, directly or indirectly, all the other phenomena of the mind. ”

“ Let us hear what the two leading nervous physiologists, of this country, have to say upon this point:
'The brain is not, strictly speaking, the organ of the mind, for this statement would imply that the mind exists as a force, independent of the brain; but the mind is produced by the brain substance; and intellectual force, if we may term the intellect a force, can be produced only by the transmutation of a certain amount of matter ”

“ The sense organs and the nervous system are just as deeply concerned, therefore, in avoiding harm as in finding food materials, and it is as important for them to do their work well in the one case as in the other. When we think of the activities of animals, for whatever purpose they are carried on, we must think of them as made up of the combined actions of the muscles, the nerves, and the sense organs, and not of any of them working by themselves. ”

“ This experiment is not easy to be made at first, but by a few patient trials the fact appears very certain; and shews clearly, that our ideas of imagination are repetitions of the motions of the nerve, which were originally occasioned by the stimulus of external bodies; because they equally expend the sensorial power in the organ of sense. ”

“ According as we count the muscles, the joints,{65} the lungs, the digestive organs as several sense organs or as a single group, the number of classes of sensations is larger or smaller. However, it matters little whether we count them or not. We know that provision is made for everything needed. Information about the most distant things is obtained through the eye; information about the things in contact with the body or the body itself comes through the cutaneous and organic sense organs. ”

“ Sensations are necessary for intelligent and purposeful action and for acquiring all kinds of knowledge. To enable the stimuli to act to the best advantage in starting the impulses, special devices, called sense organs, are employed. These receive the terminations of the neurons, and by their special structure enable the most delicate stimuli to start impulses. The simpler forms of sense organs are those of touch, temperature, taste, and smell.
Exercises.—1. Compare sensations and reflex actions with reference to their nature and cause. Give steps in the production of each. ”

“ We human folk get so much pleasure from and through the employment of our sense-organs, that it is important to remember that the primary object of the process of reception of the influences from without was not the æsthetic one of ministering to the enjoyment of life by the recipient organism, but the essentially practical one of enabling that organism to respond to these influences. In [244] other words, the raison d'être of the sense-organs is to set agoing suitable activities—activities in due response to the special stimuli. ”

“ Moreover, as G.H. Lewes says, "It is the man, and not the brain, that thinks: it is the organism as a whole, and not one organ, that feels and acts." [33]
Every faculty manifests itself by means of matter, but it is important not to confound the faculty with the corporeal organ upon which the external manifestation of such faculty depends. The word organ is the name given to a part of the human frame by which we have sensation, and by means of which we do a certain act or work; such are the organs of sight, sound, smell, taste, and touch. ”

“ There are, in fact, people who appear to think only with the brain, or with whatever may be the specific thinking organ; while others think with all the body and all the soul, with the blood, with the marrow of the bones, with the heart, with the lungs, with the belly, with the life. And the people who think only with the brain develop into definition-mongers; they become the professionals of thought. ”

“ THE first task of physiology was to localize the functions of life in the various organs of the body which serve as their instruments. Thus digestion was assigned to the stomach, circulation to the heart, respiration to the lungs; thus, too, the seat of intelligence and thought was placed in the brain. Still, with regard to the latter organ, a reservation was thought proper, excluding the idea that the metaphysical expression of the intellectual and moral powers was the manifestation, simply and merely, of the cerebral function. ”

“ That the outer world is only for my organs appears inevitable. But what is an organ except so far as it is known? And how can it be known but as itself the state of an organ? If then you are asked to find an organ which is a physical object, you can no more find it than a body which itself is a body. ”

“ From a physiological point of view, those metaphysical phenomena of thought, consciousness, and intelligence, which serve for the various manifestations of the human soul, are nothing but ordinary vital phenomena, and can result from nothing but the action of the organ that expresses them. We shall show that, in fact, the physiology of the brain, like that of all the other bodily organs, is deduced from anatomical observations, from experiments conducted physiologically, and from the teachings of pathological anatomy. ”

“ From this, we advance to the nerve centre,—the brain,—to which the nerves of sensibility run up, and from which the nerves of motion come forth. Here also there is identity in the nature of the organ, while there is variety in its size, with more or less complicated plans of arrangement, according to the extent of the nerve system of which it is the central organ. Still keeping to the human body for illustration, we may find in the most complex organism known to us illustration of what holds good in the main so far as essential structure is concerned. ”

“ The nerves and brain, together, form one great organ; and a sound state of the whole organ, even from the analogy of other grosser organs, may well be supposed to be necessary for the healthy state and perfect function of each separate part. ”

“ Animal life is composed of the action of the senses which receive impressions, of the brain which perceives them, reflects, and wills, of the voluntary muscles and larynx that execute this volition, and of the nerves which are the agents of transmission. The brain is truly the central organ of this life. Digestion, circulation, respiration, exhalation, absorption, secretion, nutrition, calorification, compose organic life, which has the heart for its principal and central organ. ”

“ But as evolution proceeds and definite organs are formed in the physical body, in the nervous [155] system, and as later, in the astral body, chakras or astral centres of sensation are formed—as this goes on, we find a more specialised being developed with definite organs. Always the organ comes after the function, and through the organ the function expresses itself more and more perfectly. That is a fundamental principle. And do not forget that in this you are on what is thought the safer ground of western science. You do not find an organ appearing before the development of its function. ”

“ All organs, which are purely animal, are penetrated or traversed by the nervous system, just as the lower systems are by the tegumentary formation. No higher organ is the wholly pure evolution of one system, but the systems ever combine with each other ”

“ The surfaces of their bodies really are sources of perception, and seats of consciousness. Man must yet learn to see with his skin, taste with his fingers, and hear with the surface of his body. The dissected nerve, or the pupil of man's eye, offers to the physiologist no explanation of its intrinsic power. Is not man unfortunate in having to risk so much on so frail an organ? ”

“ The brain, therefore, instead of being the seat of sensation, the principle of sentiment, is only an organ of secretion and nutrition, but it is an [128] organ which is highly essential, and without which the nerves could neither grow nor be preserved. ”

“ They should see that the study of the organ of thought, microscopically, chemically, experimentally, in the lower animals, in individuals and races, in health and in disease, in every aspect of external observation, as well as by internal consciousness, is just as necessary as if the mind were known to be nothing more than a function of the brain, in the same way as digestion is of the stomach. ”

“ But he thinks that along with the power, or as part of the conception of Power, the material organ is also signified. It seems to me that the organ does not enter in either of these modes, into the signification of the word. We can imagine ourselves ignorant that we possess physical organs; or aware that we possess them, but not aware that our sensations of smell are connected with them. ”

“ The animal functions, as the physiologists call them, in distinction from the organic, tend, in the process of deterioration to which age and neglect united gradually lead them, to assume the periodical or rhythmical type of movement. Every man’s heart (this organ belongs, you know, to the organic system) has a regular mode of action; but I know a great many men whose brains, and all their voluntary existence flowing from their brains, have a systole and diastole as regular as that of the heart itself. Habit is the approximation of the animal system to the organic. ”