The volunteers of the Olympic awards ceremony will not be blind for 3 to 5 minutes. It may sound like you may not agree, but in fact, if you want to stay blind for a long time, it is a contest with the body.
Blinking is a normal physiological activity. It is called blinking movement in medicine. It is actually the opening and closing movement of the eyelid. The eyelids are like a pair of curtains hanging from the outside of the eyeball, and work to open and close according to a certain rhythm. The human eye is not like a fish, and there is no transparent film protection, so blinking action is very important and is a protective job. When the eyelids are closed, the tears can be evenly distributed on the cornea and conjunctiva to keep them moist.
Want to count your own blink of a minute? It is estimated that normal people should complete blinking actions more than ten times per minute, with an average of 2-6 seconds. It takes about 0.3-0.4 seconds to complete a blink. The speed of blinking is controlled by the “blinking center” in the brain. This is completely autonomous nerve reflex. In other words, when you should blink, you don’t have to care, the brain will handle it automatically. In the event of strong light stimulation and sudden arrival of sediment into the eyes, the blinking action occurs immediately and is intense. At this time, blinking is a protective reflection.
In general, blinking is synchronized with both eyes, but it can also be controlled by humans. You must have met a friend who blinked at you, usually with one eye. This is called "directory". As a kind of body language, it can effectively transmit signals and hints. It is unique to human beings.