The structure of the brain

Let's put the rabbit to sleep. He is now lying motionless on the table. The sound of the bell does not cause him to move. Touching with a needle does not work. The rabbit does not move, but its sides rise and fall evenly. The large hemispheres are "sleeping", and the breath has been preserved. So it's controlled by some lower floor. The rabbit's large hemispheres are removed, leaving only the medulla oblongata — the area of transition to the spinal cord: the rabbit breathes as before. The experience continues. The rabbit has its medulla oblongata removed. And then the breathing stopped instantly. The pectoral muscles and lungs of the rabbit are not destroyed, but they are not able to work: the central control has died. So, the respiratory center lies in the medulla oblongata. Other experiments have shown that the medulla oblongata controls the work of the heart and blood vessels — their expansion and contraction. Chewing, swallowing, sneezing, coughing, blinking, sweating, sucking — all this depends on the medulla oblongata. And here's a dog who had his cerebellum removed. The dog can't walk. She's rocking all the time. Her paws are spreading in different directions. How will such an animal live? It turns out that a little time will pass and the dog will start walking almost normally. But there is no cerebellum. What part of the brain took over his work? Other overlying parts of the brain and the cerebral cortex came to the rescue. Receiving signal after signal of trouble, they began to do this work, and the movements got better. A person who has a damaged cerebellum resembles a person poisoned by alcohol. His hands and feet are shaking. He can't get a spoon in his mouth, fasten a button, walks, spreading his legs and arms wide. The brain stem is located directly under the large hemispheres of the brain. The lower floors — formations under the cerebral cortex — Pavlov called the subcortex. This includes the middle and intermediate brain. The midbrain lies above the medulla oblongata. His reflexes are more complicated. And even higher is the intermediate brain. He, together with the middle brain, carries out more complex and perfect motor reflexes. The intermediate brain is located in the path of all signals coming from the outside world and from inside the body to the large hemispheres. Therefore, he, as a controller, checks and clarifies all signals coming to the large hemispheres.

The most complex reflexes of nutrition, protection, reproduction — all this is the work of the intermediate brain. An important part of the brain is also laid here: the reticular formation — the "mesh". The same area of the brain, the trunk, is responsible for the thin nerves of the whole body — the autonomic nervous system. It can be called the keeper of internal order. Tissues, organs, cells in the body do not live an independent, separate life. Their work is interconnected through nerves. There are a lot of nerves. If we could look inside the body for a minute, we would see a lot of thin white laces, their knots and plexuses. These nets and meshes surround the heart, permeate the stomach, liver, intestines. They are both in the kidneys and in the small thyroid gland. These nerves are two or even five times thinner than others. The nerves of the internal organs have a special purpose — this is the autonomic department of the nervous system. We will begin to irritate one of these nerves — sympathetic: the pupil and bronchi will immediately narrow. And with irritation of other autonomic nerves — parasympathetic — on the contrary, the pupil and bronchi will expand, the heartbeat will slow down. Therefore, sympathetic and parasympathetic nerves were called antagonists. The autonomic nerves are part of the entire nervous system and perform one common task: they guard the order inside the body. The person was given a lot of physical activity and monitored for autonomic nerves. It turned out that some nerves turned on as soon as a person started working. Others came into effect somewhat later. Some nerves have actively started work, while others have finished it. So mutual opposition always goes alongside the commonwealth. We will cut out the frog's foot so that two nerves fit to the muscles of the foot — one motor from the spinal cord, the other vegetative. If we apply an electric shock to the motor nerve, the foot will pull back. If the current irritation is repeated for a long time, the muscle gets tired and stops moving. Then the autonomic nerve can be called to help. If you now irritate the autonomic nerve with a special technique, then in response to electric shock irritation of the motor nerve, the foot will begin to contract again. The autonomic nervous system has come into action. And the work immediately revived: the metabolism changed, new forces appeared. Similar phenomena are also frequent in human life. Homemade porn https://www.amateurest.com/ USA.