What kind of experience is it to be “scared stupid”

　　Tonic palsy is an instinct that can be mastered without learning, and this emergency mechanism is beyond your control, not something you can move if you want to.
　　In fact, many animals exhibit this defense response, including many insects, fish, reptiles, amphibians, birds and mammals, and one of the domestic animals most prone to tonic paralysis is chickens.
　　When ankylosing paralysis occurs, the animal will stiffen, have a weak voice, close its eyes from time to time, and lose response to the outside world. In severe cases, it will begin to tremble like Parkinson’s disease.
　　As early as the 17th century, some people discovered the phenomenon of tonic paralysis. In 1636, an Italian discovered that if you let the chicken lie on the ground, stroke the chicken’s beak with your finger, and then draw a line on the ground, the chicken will always stare at the line stupidly. Therefore, at first everyone thought this was a kind of “hypnotism” for chickens, but later everyone discovered that it was a form of animal defense.
　　The methods of putting animals into ankylosing paralysis are similar. Generally speaking, you must imitate the actions of predators and grab them, or press them on the ground, or stick them in the V-shaped groove for more than 15 seconds. Paralysis of the whole body.
　　In the wild, killer whales have been spotted turning sharks up to make them unable to move. This shark does not like to be touched, but has entered a state of tonic paralysis.
　　If it is a rodent such as a mouse, pinching the skin on their neck and imitating the movement of a cat scratching them can also paralyze their whole body. When ankylosing paralysis occurs, the body will become rigid and unable to move involuntarily, sometimes even unable to speak.
　　How can you be stiff and unable to move when you are in danger? Isn’t it easier to get caught?
　　Generally speaking, when confronted with danger, many spine and invertebrates, including humans, have a fight or flight response, that is to say, they either step forward to beat the opponent or escape.
　　When responding to fight or flight, the brain enters a very alert but analgesia mode (non-opioid analgesia). Therefore, it makes sense for many people with red eyes on the battlefield to fight heroically despite being seriously injured, because in this state of fighting or fleeing, the human brain has not noticed the pain of the wound.
　　But when it is neither possible to escape nor to be a hero, such as when the body receives a lot of creepy information (such as smell, touch) at once, the brain will enter another state (low-energy sleep mode) , And began to produce many opioids to paralyze oneself, making oneself feel no pain and fear.
　　When tonic paralysis occurs, the animal’s body becomes motionless and blends with the environment, making it difficult for the enemy to find itself, which can bring a ray of life.
　　Many predators do not like to eat dead food. For example, cats like to bite lively quail instead of pretending to be a dead body.
　　Therefore, generally speaking, after an animal struggles for a period of time, if it finds that it cannot escape, it will enter a state of tonic paralysis. After entering this state, even if they are let go, they will be “paralyzed” for a few seconds or even hours.
　　Most scientists believe that the meaning of ankylosing paralysis is to increase the probability of survival of animals when encountering predators, but in fact it is also the last gentleness that nature gives life.
　　Think about it, after many animals are bitten in their throats, their brains will produce a lot of opioids, so that they will not feel the pain of death and die in the final calm. This is equivalent to a natural euthanasia.