Talk:Ivan Pavlov

Latest comment: 15 years ago by Antiquary in topic Unsourced

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Wikiquote no longer allows unsourced quotations, and they are in process of being removed from our pages (see Wikiquote:Limits on quotations); but if you can provide a reliable, precise and verifiable source for any quote on this list please move it to Ivan Pavlov. --Antiquary 17:04, 29 August 2009 (UTC)Reply

  • After remaking the animal's organism in accordance with our design, which naturally caused more or less damage to the experimental animal, we had to find a modus vivendi for it that would ensure an absolutely normal and long life.
  • Appetite, craving for food, is a constant and powerful stimulator of the gastric glands.
  • As was to be expected, the discovery of the nervous apparatus of the salivary glands immediately impelled physiologists to seek a similar apparatus in other glands lying deeper in the digestive canal.
  • As we have seen, bread, and especially dry bread, evokes secretion of considerably larger quantities of saliva than meat.
  • At the same time this is an extremely important practical application of the power of human knowledge, which may also be of immediate use to man, who, due to the implacable fortuities of life, is often mutilated in similar, though more varied ways.
  • But man has still another powerful resource: natural science with its strictly objective methods.
  • Edible substances evoke the secretion of thick, concentrated saliva. Why? The answer, obviously, is that this enables the mass of food to pass smoothly through the tube leading from the mouth into the stomach.
  • Finally, as the digestive canal is a complex system, a series of separate chemical laboratories, I cut the connections between them in order to investigate the course of phenomena in each particular laboratory; thus I resolved the digestive canal into several separate parts.
  • From the described experiment it is clear that the mere act of eating, the food even not reaching the stomach, determines the stimulation of the gastric glands.
  • In the case of the stomach, however, the nerves of the glandular cells were always severed when constructing an artificially isolated pouch and this, naturally, affected the normal work of the stomach.
  • In this way we often had to perform very minute operations, sometimes several of them on one and the same animal.
  • It goes without saying that the desire to accomplish the task with more confidence, to avoid wasting time and labour, and to spare our experimental animals as much as possible, made us strictly observe all the precautions taken by surgeons in respect to their patients.
  • It has long been known for sure that the sight of tasty food makes a hungry man's mouth water; also lack of appetite has always been regarded as an undesirable phenomenon, from which one might conclude that appetite is essentially linked with the process of digestion.
  • It is clear to all that the animal organism is a highly complex system consisting of an almost infinite series of parts connected both with one another and, as a total complex, with the surrounding world, with which it is in a state of equilibrium.
  • It is not accidental that all phenomena of human life are dominated by the search for daily bread - the oldest link connecting all living things, man included, with the surrounding nature.
  • Long before us it was established that the work of the salivary glands is regulated by a complex nervous apparatus.
  • Mechanical influences are completely ineffective with regard to the gastric glands.
  • Only by observing this condition would the results of our work be regarded as fully conclusive and as having elucidated the normal course of the phenomena.
  • Our experiments not only proved the existence of a nervous apparatus in the above-mentioned glands, but also disclosed some facts clearly showing the participation of these nerves in normal activity.
  • Our success was mainly due to the fact that we stimulated the nerves of animals that easily stood on their own feet and were not subjected to any painful stimulus either during or immediately before stimulation of their nerves.
  • Physiology has, at last, gained control over the nerves which stimulate the gastric glands and the pancreas.
  • Precise knowledge of what happens to the food entering the organism must be the subject of ideal physiology, the physiology of the future.
  • So the stimulation effected by the act of eating reaches the gastric glands by means of the nerve fibres that are contained in the vagus nerves.
  • Thanks to our present surgical methods in physiology we can demonstrate at any time almost all phenomena of digestion without the loss of even a single drop of blood, without a single scream from the animal undergoing the experiment.
  • The digestive canal represents a tube passing through the entire organism and communicating with the external world, i.e. as it were the external surface of the body, but turned inwards and thus hidden in the organism.
  • The first stage through which the food substances introduced from without must pass, is the digestive canal; the first vital action on these substances, or to be more exact and objective, their first participation in life, in its process, constitutes what we call the digestion.
  • The physiologist who succeeds in penetrating deeper and deeper into the digestive canal becomes convinced that it consists of a number of chemical laboratories equipped with various mechanical devices.
  • Thus, the purposeful relationship of phenomena is based on the specificity of the stimuli, that correspond to similarly specific reactions.
  • When the dog is repeatedly teased with the sight of objects inducing salivary secretion from a distance, the reaction of the salivary glands grows weaker and weaker and finally drops to zero.
  • While you are experimenting, do not remain content with the surface of things. Don't become a mere recorder of facts, but try to penetrate the mystery of their origin.
  • With each meal, when edible substances find their way into the oral cavity, thick and viscous saliva containing much mucus flows out of these glands.
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