Sechenov, Ivan Mikhailovich

Sechenov, Ivan MikhailovichThe great Russian physiologist, founder of the Russian physiology Years of life: 1829-1905 The experience of the "White lady" was the title of one of his experiments a scientist. Actually it involved not a lady, and ordinary kwakwa. On the lab table was a simple tripod, it was hanging frog. The name was given in jest: that day the scientist listened to Opera, Baldie "White lady". In the experiments on frogs Ivan Mikhailovich Sechenov - founder of Russian physiological school discovered the phenomenon of inhibition in the Central nervous system. I. M. Sechenov he received his medical education at the University of Moscow. After graduation, he went abroad and worked for several years in the laboratories of large German physiologists. He was engaged in studying the impact of alcohol on the human body. This work required a detailed study of changes in blood composition, in particular changes in the abundance and distribution of blood gases. How to trace these changes? It was necessary to draw blood, dissolved gases, so to speak, "deflate" them out. Sechenov invented for this particular device and worked with him for many years. These studies resulted in others, and the result was sechenovskiy the law of solubility of gases in solutions of various salts. The results of their work Sechenov reported in the thesis "Materials for future physiology of alcohol intoxication". He received his Ph.D. in Medical-surgical Academy in St. Petersburg and was appointed Professor. In the first years of its operation Professor Sechenov began to talk to students about the great role of the external environment in living organisms. It is associated with a living organism; to isolate the organism from the environment is impossible: they are inseparable. All complex manifestations of animal life associated with the activity of the Central nervous system. Received from the outside irritation entails the initiation of the corresponding part of the nervous system, it induces the activity of certain organs. Externally, it is expressed in different actions, movements. Any irritation causes one or the other "answer" of the nervous system is the reflex. Reflexes can be simple or complex, but any one of them passes through the reflex arc. It consists of a conductive path (from the point of stimulation to the brain), the switching part (corresponding to the part of the brain) and centrifugal (nerve and the body, through which will be given "the answer", i.e. implemented reflex). Here are a few simple examples. Decapitated frog draws back foot, if it is pinched. It also pulls the foot, which dripped acid. If her abdomen is to put a piece of paper moistened with acid, the frog looks like his foot. Obviously, the reflex arc is closed in the spinal cord, because the head of the frog is cut off and brain no. Really, is this frog to destroy the spinal cord, as the foot ceases to otdelyvatsya and pinch and from the acid. It was one observation. And here is another. If the annoying cardiac branches of the vagus nerve, heart "stops": it ceases to decrease its activity is suppressed, inhibited. Sechenov knew this fact, but he was interested in more. Man can by his will to suppress certain reflexes, for example, to delay the respiratory movements. Does the brain mechanisms that delay the movement"? This question asked a Sechenov. He opened the frog skull and exposed brain. As usual, the frog was pulling back his foot soaked in acid. The scientist began carefully, layer by layer to separate the brain from the spinal cord, starting with the frontal lobe. Every time he put on the cut crystal of table salt (salt is a strong irritant) and watched the foot. She jerked, as soon as it hit the drop of acid. And now cut the optic tubercles, crystal salt is put on the foot dripped acid, but... foot barely moved, and then only with great delay. New experiments again showed that severe irritation of the optic tubercles causes suppression of reflex foot, slowing it, and spinal cord in this inhibition does not participate. It became clear that the centers of the brake are in the brain. This phenomenon has received the name sechenovskiy braking. Opening Sechenov phenomena Central inhibition was of great importance.


  > > > >  

Похожие статьи

Ваше имя
Ваша почта
Город, область
Рассылка комментариев





Ввести код: