Our 5 sensory organs that enable us to see, smell, taste, hear and feel are responsible for the way we perceive the world. They allow us to be aware of our environmental surroundings; even when we are a sleep. Our eyes, by far are the most important sense organ. 80 percent of all perceptions are due the impressions made by our sight. The primary function of the eye is to focus, project and then transform images received into electric impulses; that are carried by the optic nerve to the brain. However, there is another important function that the eye carries out, i.e. blinking. But have you ever wondered why do we blink?
How many times do we blink?
There are two major types of actions that the human body conducts- voluntary and involuntary. Actions we consciously conduct, like eating are voluntary actions. Since we do not consciously make an effort and can only partially control breathing or blinking, these become involuntary actions.
On an average infants blink once or twice every minute and adults blink 15-20 times in a minute, 1,200 times in an hour and about 28,800 times in a day. Researchers say, this is more than the required amount of blinking. On the basis of these numbers, it can be said that we spend 10% of our waking hours with our eyes shut.
What makes us blink?
Most often blinking takes place involuntarily. Sometimes it is in response to external stimuli, such as dust and other fragments. Other times, we blink voluntarily to relax our fatigued eyes or to clear our blurry vision.
We primarily blink to keep our clean, moisturised and lubricated. Each time we blink, a minuscule amount of tears from the tear glands are secreted, wetting the lower third of the cornea.
While tear secretion lubricates the eye, blinking also brings nutrients to the eye surface, keeping them healthy. A s result of this process, the images the retina receives is brightened and clear.
Why do we blink more often than required?
Blinking became a physiological riddle when scientists figured that we blink more than required for us to just keep our eyes lubricated.
Further research indicated that blinking also results in more focused attention on the task at hand. When we blink, we release attention from external stimuli, bring back our focus and also assimilate the information we have received. The happens because- when individuals blink, the ‘default mode network’ in the brain gets activated. As a result our brain enters a period of wakeful rest, helping us focus better. Hence, you would have found your self closing your eyes when you trying to focus, gather your thoughts or calm yourself down.
Research also showed that blinking does not take place randomly, but at regular intervals. This however depends on the activity we indulge in. We blink half as frequently when we are concentrating on something like reading. Also blinking takes place usually at the end of sentences while reading and when speakers pause.
You must have also wondered, how is it that we experience reality in continuity despite the momentary blackouts. This is because our brain has this amazing mechanism to suppress this blackout and keep the visual experience continuous.
Also, read about our previous blog The colours you see are different from mine. But Why?Subscribe to Engage Learning and improve the way your child learns.