This post is also available in Dutch.
1. Blinking is one of the fastest movements
The phrase in the blink of an eye doesn’t come out of nowhere: a blink can last for as little as one-tenth of a second and is thus one of the fastest movements the human body produces.
2. We blink to wet and protect the eye
The main reason we blink is to protect the eye from things that don’t belong there, such as allergens, pollutants or small insects. Blinking also importantly provides moisture to the eye and cleans it. Each time our eyes close, salty secretions from the tear glands are swept over the surface of the eye, flushing away small dust particles and lubricating the eyeball.
Interestingly, we blink more often than is necessary to keep our eyes clean, moist, and protected. So, what else makes us blink?
3. How often we blink depends on the task we do
Scientists have shown that blink frequency (i.e. how often we blink) and duration (i.e. how long our blinks last) vary under different conditions.
We normally blink approximately 8 to 21 times per minute. However, when engaging in more difficult tasks or conversations, blink frequency can double.
On the contrary, when we are visually focusing on something, our blink frequency often drops. For example, when reading or (binge-)watching Netflix, we blink less (4.5 blinks per minute on average).
We typically blink during breaks: when finishing reading a sentence or at the end of movie scenes. One suggestion is that blinking may indicate a form of momentary rest for the brain, allowing the mind to wander and go offline. In this way, blinks are like punctuation marks of the mind, signalling a pause in brain activity related to the task at hand.
4. How often we blink is influenced by our emotions
Although the impact of mental processes on blink frequency is still under investigation, we know that blink frequency can also be influenced by internal factors such as fatigue, stress or emotions. For example, when we experience emotional excitement, anxiety or frustration, we blink more often. When we day dream, on the other hand, we apparently blink less.
5. Blinks are important in face-to-face communication
Blinks also seem to be important feedback signals in interactive face-to-face communication. During a conversation, for example, when listeners blink more slowly speakers react by giving a shorter answer. In this situation, long blinks seem to signal: “I’m good, I have received enough information”.
As you can see, a lot can happen in the blink of an eye. Although blinking seems minor to us, it’s essential for keeping our eyes healthy. Blinking also helps us focus and is even an important tool for communication. So what about you? Did you blink enough today?