How do blind people know the law of day and night? How is it formed?

Everyone knows that blind people can't see images with their eyes, so some people are curious. Since the blind can't see, can they know the law of day and night? How to perceive the beginning and end of a day? With questions, let's look down together.

First of all, blind people have a circadian rhythm, which mainly depends on the internal biological clock and social information perception, such as three meals a day, and conversations with friends can let them know the changes of day and night.

Let's first understand the relationship between light (photosensitivity) and circadian rhythm: light will be projected on the retina and transmitted to the suprachiasmatic nucleus (SCN), and then the suprachiasmatic nucleus will transmit rhythm signals to various parts of the body such as melatonin secretion, liver function and intestinal peristalsis.

Cells have their own rhythms, and these genes will change when cultured in a small medium. But without light, when SCN is adjusted, they will be chaotic. The rhythm of each cell will have different changes, and the important role of SCN is to synchronize the rhythm of its downstream cells through neural signals.

When the time clues from the environment are not fully accepted, the human body's own circadian rhythm will run in a cycle of nearly 24 hours, which will actually be slightly more than two hours.

Because the blind can't see or feel light, and the biological clock is not regulated by light, the blind are more regulated by external information, such as social activities, clocks, eating and so on. However, this adjustment can not completely replace the function of light, so some blind people will sleep upside down day and night and lose sleep at night.

Blind people live hard in this world because they have no ability to see this beautiful world clearly, which is unfair to them. So we should care about them. If we see blind people in trouble on the road, we should try our best to help them and let them feel the beauty of the world.

After reading the little knowledge about the blind, do you have it now? Blind people can feel the change of day and night.