England – We have long believed that the main reason we blink is to keep our eyes moist, and to clean out dust and impurities to help prevent infection and injury, when needed.
But a team of scientists at the University of Rochester discovered an unexpected reason why we blink so much, and they said it actually helps us process visual information.
The team explained that if the function of blinking were simply to prevent dry eyes, we would blink less.
On average, humans blink regarding 14-17 times per minute, which amounts to more than 20,000 times per day.
Although each blink lasts only between 0.1 and 0.4 seconds, in total this means that we spend approximately 8% of our waking hours with our eyes closed.
To investigate this extra time with our eyes closed, researchers in the new study tracked human observers’ eye movements as they viewed a range of stimuli, such as patterns, that had different levels of detail.
They then linked this to computer models and spectroscopy that estimates the strength of the signals, to find out how blinking affects vision and the way the brain processes it.
They found that blinking helps people take in the “big picture” of a scene, and notice large-scale patterns that change slowly.
“By modulating the visual input to the retina (the back of the eye), blinking effectively realigns visual information,” said Professor Michele Rucci, co-author of the study.
The researchers discovered that the rapid movement of the eyelid during blinking changes the light patterns that stimulate the retina. This sends a different type of visual signal to the brain compared to when our eyes are open and focusing on something.
“Contrary to common assumption, blinking improves – not disrupts – visual processing, and significantly compensates for the loss in exposure to stimuli,” explained the study’s lead author, Bin Yang.
The study was published in the journal PNAS.
Source: Metro
#Discover #unexpected #reason #blink
2024-04-18 18:18:34
