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What happens when a piece of brain tissue is cut off?

  In the movie “Hannibal”, there was such a frightening scene: a person’s skull was opened, and the chief knife cut off a piece of his brain tissue, roasted it and fed it to him, and he ate it with relish. Is this scene believable? Can a person’s brain tissue be cut off and still be able to “taste” his own brain tissue comfortably?
multi-function brain

  The brain is a very complex organ, and so far scientists have not fully understood the functions of each area of ​​the brain. According to existing cognition, we tentatively divide the brain into frontal lobe, temporal lobe, parietal lobe and occipital lobe. What will happen to people if these places are dug up?
  The frontal lobe is the center of people’s advanced intellectual activities, and controls the key functions of the human body such as consciousness and communication, memory and attention, and voluntary movement. Therefore, if the removed brain tissue is located in the frontal lobe area, the consequences are the most difficult to estimate. It may become a fool, it may become dumb, it may become a lunatic, but it may not change at all, just like ordinary people.

  An American railroad worker named Gage suffered severe damage to his frontal lobe when an iron rod was accidentally pierced through his brain. After five months of treatment, he finally survived. But after recovering from the illness, Gage’s temperament changed drastically, from a mild-mannered, polite gentleman to an irritable, foul-mouthed nuisance whose friends and family found it difficult to accept. This is exactly the consequence of damage to the frontal lobes. People lose the ability to self-control and self-awareness. In the past, doctors have performed multiple frontal lobotomies to treat mental illness. Most of the patients survived after surgery, but there were more unforeseen consequences. Such operations are now banned.
  The function of the temporal lobe is similar to that of the frontal lobe, and it is also responsible for important functions such as language and memory, the most obvious of which is the ability to control listening, speaking, reading, and writing. When the temporal lobe is removed, the patient first loses hearing, and also becomes incoherent and speaks incomprehensible words. In addition, although the patient’s vision and movement are fine, he is unable to read or write and becomes “illiterate” because he cannot understand the meaning of words.
  The “vegetative people” we often see in movies and TV dramas are often patients with damaged parietal lobes. The parietal lobes control the five senses and movement, so vegetative people will show motionless, unconscious state. Of course, if the parietal lobe is not completely destroyed, but some functions are left, there will also be a dumb robot or a semi-vegetative person who can’t move but is conscious.
  The occipital lobe is mainly related to vision. When the brain is strongly oscillated, there will be the illusion that there are small stars in front of the eyes, which is caused by the abnormal operation of the occipital lobe neurons under the shock wave. But if the occipital lobe is removed, people are not blind, because the photoreceptor system is not damaged and there are other areas of the brain that can process visual information, but the information will be confused, and people will “call it a horse”. In 2011, scientists once treated a peculiar mental patient. In her eyes, everyone has a “dragon face” with a blue face and fangs, and even various common things in life, such as TV sets, ceilings, desks and chairs, etc. , once you stare at it for a long time, these things will also turn into “weird dragons” and rush towards her. It was diagnosed that the patient had an abnormality in the occipital lobe region.
part that cannot be ignored

  We have divided the brain into four major regions, but in addition to these places, the brain has many scattered brain tissues and cranial nerves. Although these places are too small to be divided into any lobe, if one of them is arbitrarily removed One, there will be serious consequences.
  In fact, if you open the human skull, the first thing you see is not the four major divisions of the brain, but the white bundles of nerve fibers that connect the left and right sides of the brain. In fact, if you open the human skull, the most What you see first is not the four major divisions of the brain, but the white bundles of nerve fibers that connect the left and right sides of the brain in

  If the corpus callosum is removed or ruptured, the two cerebral hemispheres will no longer be able to communicate. That is to say, the two hemispheres can complete learning and memory independently without being disturbed, which improves the ability of learning and memory to a certain extent, but cannot Live in harmony. In the movie “Rain Man”, there is a character with extraordinary memory but low intelligence, Raymond. He can accurately remember people and things ranging from phone numbers to every corner of the city, but he can’t understand the information and take care of himself. This character has a prototype, and he is Kim Peake, an autistic patient in the United States. Pique showed the same symptoms as Raymond, but he had an excellent memory but was unable to communicate with people and deal with the little things in life, and he did so because the corpus callosum was severely underdeveloped, and there was even no nerve tract.
  In 1861, the French doctor Paul Broca received a poor patient. He was completely paralyzed on the right side of his body, had a serious skin disease all over his body, had no relatives to take care of him, and could not speak a complete sentence, but could only utter something like “tan”. ”, so the doctors and nurses in the hospital called him “Tan”. This kind of disease is very strange, why can’t you say other words when you can speak clearly? Broca ruled out intellectual disability because Tan could clearly remember the length of the hospital stay and the sequence of paralysis in various parts of the body; Tan’s vocal organs were fine, and once Broca accidentally poured hot water on the tank. On his thigh, Tan reflexively scolded a foul language; Tan’s auditory comprehension ability was also very good, and he could answer questions with gestures according to Broca’s questions. None of these possible reasons for aphasia were wrong, and Broca was puzzled.
  It was not until Tan’s unfortunate death that after dissecting his brain, Broca learned the truth. It turned out that an area between Tan’s frontal and temporal lobes had been damaged, and the nearby brain cells had been necrotic. Soon another of Broca’s patients with a similar condition died, and Broca also found lesions in the same area of ​​his brain. So Broca reasoned that this area was the site of language production, and if it was damaged, people would not be able to speak normally. Since then, this area has been named “Broca District”.
  There are also many important scattered pieces of the brain, such as the hippocampus located near the temporal lobe and near the brain limbs, which have the role of memory and spatial positioning. Once removed, people’s past memories can be retained, but there is no way to learn new things. Next to the hippocampus are the amygdala and the nucleus accumbens, which are the emotional perception centers of the human body. After being cut off, people will become indifferent, and there is nothing that can make him feel happy or fearful.
Other areas of the human brain

  Speaking of which, it seems that the removal of various parts of the brain will produce various defects, but it will not be life-threatening. If the frontal lobe or nucleus accumbens is removed, maybe the patient will be able to happily eat his own brain. Organization. So what happens when the rest of the brain is removed?
  The thalamus is located on both sides of the brain and is the most important sensory relay station, transmitting signals from sensory nerves to the cerebral cortex, so that people can develop the five senses. The hypothalamus is the nerve center that regulates visceral and endocrine activities, and many basic physiological functions are regulated by it, including thermoregulation, food and water intake, and sleep awareness. It can be seen from this that if the thalamus is removed, the patient may not have any problems for the time being, but he must be dead soon. Think about it, a person who does not eat well, sleep well and has no perception, what fun would he have in life? Can it be said?

  The cerebellum is located at the back and lower part of the brain and is mainly responsible for motor regulation and balance maintenance. If the cerebellum is removed, the person loses the ability to regulate physical activity. Even if he can stand up, he can only be like a robot. Every step he takes, he has to work hard to coordinate his limbs and think in a direction. Maybe he can’t go very far. It will fall down staggering like drunk, and because of the inability to exercise, the muscles will slowly atrophy until finally paralyzed in bed.
  Now, we have finally cut to the last part of the brain – the brain stem, which is located between the brain and the spinal cord. Its function is to maintain the individual’s life, including essential physiological functions such as heartbeat, breathing, and digestion. Therefore, if the removed brain tissue is located in the brain stem , Basically, this person is out of luck. Basically, because the brainstem is also divided into four parts according to the location, the midbrain, the pons, the reticular system and the medulla. will die immediately. And if other parts of the brainstem are cut off, there will only be “slight” reactions such as not sleeping well, not blinking, etc. But these parts are so close to the medulla oblongata, how can they not accidentally injure the medulla oblongata?
  The structure of the brain is very precise and closely related. It can be said that “one hair can move the whole body”. Therefore, whenever the brain is injured or there is a brain disease that requires surgery, doctors are cautious and ready to go, and the sequelae of brain surgery are also The most unpredictable, so we have to take good care of our brains.

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