Why are the eyes not afraid of the cold?

Because there are no cold-sensing nerves in the eyeballs. There are no blood vessels in the cornea of ??the eyeball, so heat dissipation is relatively slow. No matter how low the outside temperature is, the eyes will not feel cold.

1. Reasons why people feel cold

The human body surface is unevenly distributed with many receptors (also called "cold spots" and 'hot spots') that can sense changes in cold and warm. Generally speaking, there are more cold spots than hot spots. When the outside temperature drops, the skin temperature also drops, which stimulates cold spots on the epidermis. The cold spots are then transmitted to the brain through the nervous system, making people feel cold.

2. The "warm-keeping method" of the eyes

The human eye is composed of the eyeball, conjunctiva and eyelid skin. The cornea and sclera of the eyeball are the same as the surfaces of the internal organs. There are no heat and cold receptors, and there are few cold and hot spots on the conjunctiva and eyelid skin.

So, when the external temperature changes, there are no receptors to report to the brain, and the eyes are extremely slow to feel the changes in hot and cold. Of course, the reason why the eyes are not afraid of cold is also because the eyelids are constantly opening and closing and the eyeballs are constantly rotating, thus generating abundant heat. Even in the cold weather, the temperature of the eyeball surface is above 10°C.

Extended information

To avoid eye injuries due to severe cold, you should do the following:

1. Keep warm when going out in cold weather

When cold air hits, keep warm and reduce or even avoid unnecessary outings. Especially the elderly with a history of glaucoma should avoid going from warm indoors to cold and windy outdoors immediately. When going out, you can Stand in the corridor or at the door for a while to allow your body to slowly adapt to the cold outside environment. In addition, you can also wear glasses when going out to protect your eyes from the cold air.

2. Pay attention to maintenance when using your eyes in daily life

When the weather is cold, be careful to avoid working in front of the computer for a long time and reading at close range for a long time. Especially for those who wear contact lenses for a long time, their eyes are very easy to dry. You can take a break and blink your eyes after working for a period of time, or apply hot towels to your eyes to relieve the symptoms of dry eyes. Pay attention to this in indoors with open heating. Very moisturizing.

3. Eye care for special groups

People with a history of hypertension, diabetes, etc. should pay attention to controlling blood pressure and blood sugar during the cold season to avoid abnormal retinal blood vessel shapes or Blockage can cause glaucoma. For those patients with a history of glaucoma, attention should be paid to reexamination and intraocular pressure monitoring. In addition, you must also regulate your emotions, pay attention to maintaining a happy mood, and avoid excessive mood swings.

People's Daily Online - The cold is coming? Your eyes are also afraid of the cold!