What are the causes of reflexes? Detailed answer

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What are the causes of reflexes? Detailed answer

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What are the causes of reflexes?

Remember when you go to the doctor for a checkup, he asks you to cross your legs and then hits your knees with a rubber mallet? This doctor checks for reflexes. In this case, this is a manifestation of a special reflex called the knee reflex, since the hammer strikes the knee nerve.

What happens when a hammer hits a nerve? Excitation is transmitted from the nerve ending to the spinal cord. There it is instantly transmitted along the motor nerve to the muscles of the leg. The leg twitches as if you are kicking someone in self-defense.

Such an action is reflex, i.e. automatic. We don't control it. This action is not subject to awareness. For example, when you go to bed and close your eyes, it happens by your will. But if a speck of dust gets into your eye, then you, regardless of your desire, immediately close it.

This automatic movement is a reflex. We can characterize a reflex as a response of the body to external stimuli in the absence of our influence on it. How does this happen?

The spinal cord is the transmission point of our reflexes. When the nerve endings located on the skin are irritated, the irritation passes through the spinal cord, and then is transmitted to the motor nerves. Through the motor nerves, the excitation reaches certain muscles, which sets them in motion. Nerve impulses cannot bypass the brain. More than 90% of all actions that are controlled by the human nervous system are reflexes!

Author: Likum A.

Random interesting fact from the Great Encyclopedia:

Why did the Pentagon initially have twice as many toilets as needed?

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