What’s the point of blinking?

Blinking, a reflex that we perform thousands of times a day without thinking about it, is nevertheless an important phenomenon for the functioning of our vision. This seemingly harmless movement plays a vital role in keeping our eyes healthy, protecting our eyes from external aggression, and even in our visual perception. Let’s look at the importance of this mechanism in detail.

Moisturizing and lubricating function

Blinking your eyes provides uniform distribution tear film, a thin layer of fluid that covers the surface of our eyes. This film, produced by the lacrimal glands, consists of three layers: lipid, aqueous and mucin. This ensures that the eyeballs remain moist, avoiding dry eyes and irritation.

• The outer lipid layer reduces evaporation.
• The aqueous middle layer moisturizes the cornea.
• The inner layer of mucin allows the aqueous layer to adhere to the cornea.

A full blink distributes these layers evenly, allowing the eyes to remain lubricated and comfortable. The average person blinks 10 to 20 times per minute, which is approximately 14,400 blinks per day. However, people who work in front of a computer screen tend to blink less, which often leads to dry eye syndrome.

Protection from external attacks

Blinking is also a protective reflex. When a foreign body, such as dust or an insect, approaches the surface of the eye, rapid blinking is automatically triggered to expel the unwanted element. This mechanism is critical to preventing corneal damage.

The eyelids act as a shield, preventing particles from entering the eyes. They also keep the surface clean by blowing away debris and dust when blinking. Fast reflexes (on the order of a few milliseconds) provide effective protection against many potential attacks.

Maintaining vision and concentration

Surprisingly, blinking helps too. stay focused and support this vision. When performing a task that requires increased visual attention, such as reading, blinking provides much-needed micro-breaks for our brain. By briefly interrupting visual input, the brain is able to interpret and process the information it has already received.

Neuroscience research shows that the brain uses these moments to organize visual information, thereby avoiding cognitive overload. During these breaks, brain activity in areas responsible for processing visual information decreases, while other areas associated with attention and relaxation are activated.

Neurological and behavioral coordination

The blinking process involves complex neurological coordination between different parts of the brain. Blinking can be voluntary, but in most cases it is involuntarily controlled by the brain stem. The circuits involved include the cerebral cortex, which controls voluntary blinking, and subcortical structures such as the oculomotor nucleus, which is responsible for reflexive blinking.

Behavioral factors such as anxiety or fatigue can also affect blink rate. For example, people under stress may blink more frequently, and fatigue tends to reduce this frequency. These changes are often indicators of overall well-being.

Eye blinking disorders

When blinking is impaired, it can lead to eye and neurological problems. The most common malfunctions include:

• Blepharospasm : Excessive, uncontrolled blinking, often associated with irritation or stress.
• Lagophthalmos : Inability to close the eyelids completely, often due to facial palsy or mechanical problems.
• Dry eye : Defect in tear production or change in tear film distribution.

These disorders often require medical attention because they can damage the cornea and impair vision.

Blinking, a daily automatic gesture, is essential for maintaining eye health, protecting against external aggressors, and facilitating visual processing. Understanding the basic mechanism and benefits of this reflex helps us realize the importance of our eyes and the critical role our eyelids play in protecting them.

During periods of intense work in front of screens or during activities that require prolonged visual concentration, it is extremely important to remember to blink regularly to keep your eyes well hydrated. This can be as simple as taking a break every 20 minutes and remembering to consciously blink, helping our eyes continue to provide clear and comfortable vision.