Nervous system

“ All the operations of the nervous system are performed by the influence of the nervous fluid, which is generated in the gray portions of the brain and ganglia. Whenever a nerve is cut off from its connection with these nervous centres, its power is gone, and the part to which it ministered becomes lifeless and incapable of motion. ”

“ The Sympathetic Nervous System.—Connected with the central nervous system is that part of the nervous apparatus that controls the muscles of the digestive tract and blood vessels, the secretions of gland cells, and all functions which have to do with life processes in the body. ”

“ The nervous system emerges at length freely above the other systems, and it is no longer its mass, but its organs which impart character to the animal. The nervous organs are, however, simply the organs of sense. ”

“ Yet, no one denies that each is a morbid affection of the central nervous system; this being granted, the rejoinder to those who insist on the extreme unlikeness is that the lesion in one is at the very bottom, in the other at the very top, of the central nervous system ”

“ Because the nervous system has accumulated, during the hours of rest, a fresh amount of that vital force which we call the nervous fluid, and by which the various organs of the body are excited to perform the duties assigned to them. ”

“ In short, a careful review of all the facts available to date leads us decidedly to the conclusion that the nervous system is the toughest and most resisting tissue of the body, and that its highest function, the mind, has the greatest stability of any of our bodily powers. ”

“ That what has been called nervous system consists of two parts, one purely sensorial, the other conveying impressions.
That the three powers are combined in the most perfect animals. That the muscular may be destroyed through the nervous system, and the nervous through the sensorial; and though each is not strictly dependent on the others, they are so connected that no one can exist long without the others. ”

“ As we are brought face to face with almost every possible condition of the nervous system, our opportunities for investigating the various manifestations of nervous energy, its source and supply, may we not equal any other specialty in solving the great problem of cause and effect manifesting nervous energy? ”

“ It is now generally conceded that the nervous system controls all of the physical functions to a greater or less extent, and also that most of the symptoms encountered at the bedside can be explained and interpreted from the stand-point of nervous physiology. ”

“ When studying the physiology of nerve-action as we see it in animals, children, and men, and the pathology as we see it in various nervous disorders, as acute insanity, 'delirium tremens, and the like, we soon become aware of the fact that the well-being of the entire nervous system depends mainly on its renovation during a state of repose; and that for the higher portion of the brain, at any rate, this state of repose and rest is synonymous with healthy sleep. ”

“ The brain and nervous system are divided into distinct portions, each having different offices to perform, and each acting independently of the others; as, for example, one portion is employed by the mind in thinking, and in feeling pleasurable or painful mental emotions; another in moving the muscles; while the nerves that run to the nose, ears, eyes, tongue, hands, and surface generally, are employed in seeing, hearing, smelling, tasting, and feeling all physical sensations. ”

“ The physiology, however, of the brain and nervous system is in a state of such rapid advance, and is continually bringing forth such new and interesting results, that if there be really a connection between mental peculiarities and any varieties cognizable by our senses in the structure of the cerebral and nervous apparatus, the nature of that connection is now in a fair way of being found out. ”

“ Nerve Supply and Health.—We know now that when a part of the body is cut off from its connections with the central nervous system, it begins at once to be lowered in vitality and gradually tends to dissolution. ”

“ We must suppose, in short, that physical processes constitute a locked system, every subsequent state of which is fully accounted for by the immediately preceding state; that the nervous system is a highly complex mechanism for adapting the movements of an animal to environing conditions in a manner useful to the animal; and that consciousness is a parallel manifestation, concomitant to certain processes in the highest nerve-centres. ”

“ But, when we have got to nerve element and nerve force, it behooves us not to rest content with the general idea, but to trace, with attentive discrimination, through the nervous system the different kinds of nervous cells, and their different manifestations of energy. ”

“ By the state of the nervous system volition is modified or controlled, the operation of the senses accelerated or retarded, the muscular movements rendered feeble and uncertain, or strong, vigorous, and energetic; in fine, the chief manifestations of life, thought, volition, and independent22 motion, are all regulated by the condition and structure of the central nervine masses. ”

“ The next thing which we have to consider is how knowledge of the external world reaches the central nervous system. Sensations of touch, temperature, and pain are fairly easy to understand, since the nerves which convey such impressions have numerous endings in the skin. End organs of nerves in the joints and muscles doubtless enable the animal to perceive and estimate strain and resistance in moving or lifting things. ”

“ For the entire nervous system is nothing but a system of paths between a sensory terminus a quo and a muscular, glandular, or other terminus ad quem. A path once traversed by a nerve-current might be expected to follow the law of most of the paths we know, and to be scooped out and made more permeable than before ”

“ STRUCTURE.—The nervous system includes the brain, the spinal cord, and the nerves. It is composed of two kinds of matter— the white, and the gray. The former consists of minute, milk-white, glistening fibers, sometimes as small as 1/25000 of an inch in diameter; the latter is made up of small, ashen-colored cells, forming a pulp-like substance of the consistency of blancmange. ”

“ whilst the study a posteriori of the distribution of consciousness shows it to be exactly such as we might expect in an organ added for the sake of steering a nervous system grown too complex to regulate itself. ”