Hallucination: The human brain’s travel through reality


Hallucination is the feeling of something appearing out of nothing. Things that clearly do not exist appear in the brain constantly, as if you have traveled to another world. The famous Nobel Prize winner John Nash suffered from severe visual and auditory hallucinations, which prevented him from working normally for 30 years. After the age of 60, his condition gradually improved and he was able to resume research. Hallucinations do not only "favor" geniuses, ordinary people may also be troubled by them and suffer from nightmares.

There are two main theories on the origin of hallucinations: one is the out-of-control theory, in which the sensory pathways are controlled by the prefrontal cortex. When the control disappears, the sensory cortex and subcortical nuclei of the brain will be overactive and cause hallucinations; the other is that the brain According to the cortical stimulation theory, pathological stimulation causes abnormal excitement in the sensory cortex and association cortex of the brain, activating past memory traces and recreating vivid and vivid images. When the image reaches the same vivid level as the real-life stimulation, the patient believes that it was transmitted through the senses.

Auditory hallucinations are the most common hallucinations and one of the common symptoms of schizophrenia. There were a considerable number of schizophrenia patients in the process of human evolution. The living environment at that time was harsh, and there were no tools to soothe the soul such as philosophy and psychology. Wizards used craniotomy to release the "evil spirits" in the patients' brains. Some patients Miraculously survived. There are traces of healing on the edge of the "brain hole", indicating that he lived for a longer period of time after the operation. Modern medicine has discovered that some patients with schizophrenia have reduced temporal lobe volume and are accompanied by auditory hallucinations. Electrophysiological experiments have proven that stimulating the temporal lobe can cause auditory hallucinations in patients. The temporal lobe is where the auditory center is located, adjacent to the limbic system (the brain area that produces emotions). Temporal lobe abnormalities are related to auditory hallucinations and emotional disorders, but pathologically, no characteristic lesions have been found, and the specific pathogenesis is unclear.

In addition to auditory hallucinations, humans also have various hallucinations such as visual hallucinations, olfactory hallucinations, phantom tastes, and tactile hallucinations.

Drugs such as omeprazole, voriconazole, and amantadine may cause visual hallucinations, as may puffer fish, poisonous mushrooms, datura, and black-feathered cactus. After some people eat Amanita muscaria, the things in front of them become larger or smaller, like a magic mirror. The poisoned person sometimes dances with excitement and sometimes becomes dejected. The common name of the small American boletus mushroom is "seeing hands green", which will make the person who eats it by mistake "there are busy little people everywhere in front of you. There are countless little people on the table, on the walls and even on the big trees, just like walking into a fairy tale." "Description of Lilliput".

The phantom smeller often smells disgusting smells such as rotting food, corpses, chemicals, etc. This makes the phantom smeller depressed and often has delusions of persecution, thinking that someone is using poisonous gas to harm him. People who phantom smell are usually conscious and have normal expressive abilities. Hallucinations may be caused by drugs, epilepsy, brain tumors and other diseases. If you have hallucinations for more than a week, you should go to the hospital for detailed examination.

People with hallucinations taste a special strange smell that does not exist in food or water, and often refuse to eat or drink. Hallucinations may be a symptom of diseases such as schizophrenia and epilepsy.

A tactile person experiences being touched without actual tactile stimulation. Anesthetics or sedatives such as chloroform, diazepam, laughing gas, propofol, ketamine, and fentanyl can all trigger phantom touch. Anesthetics that act on the central nervous system mostly interfere with the body's perception of pain by inhibiting the cerebral cortex. It is possible that while inhibiting the cerebral cortex, there may be deinhibition of subcortical nuclei.

Hallucinations are not entirely a disease, and normal people occasionally experience hallucinations. When we look forward to our loved ones coming home soon, we hear footsteps and knocks on the door, and sometimes we can’t help but go to the door to take a look. Various hallucinations are also prone to occur after fatigue or drinking. People with rich imagination and creativity are more likely to have hallucinations. Artists such as Yang Ningshi, Mi Fu, Liang Kai, Xu Wei, Bada Shanren, and Gu Minzhi are all known as "crazy"; foreign artists such as Van Gogh and Munch , Eugene O'Neill, Camus, and Beckett have all been diagnosed with mental illness.

In real life, we encourage "fantasy" and do not welcome hallucinations. How to avoid hallucinations? Protecting physical and mental health is the basis for preventing hallucinations, which requires cultivating good living habits in daily life, paying special attention to the maintenance of sensory organs, which are the normal sources of various sensations. If there is a problem with the sensory organs, it is easier to be disconnected from the real world. The brain will smear and tamper with it on its own initiative, and hallucinations will take advantage of it.

Hallucinations are not surprising. If the human brain followed the rules like a machine, there would be no advanced functions such as association, reasoning, and enlightenment. Occasionally, we can allow ourselves to escape from the tedious or monotonous reality and appreciate the splendor of daytime shooting stars.