What's the reason behind our frequent blinking? It's not just to maintain moisture!

• Published date: 18 April 2024
• Author: JUDY SIEGEL-ITZKOVICH
• Publication title: Jerusalem Post, The: Web Edition Articles (Israel)

But why do we do it? Obviously, blinking lubricates the eyes and protects them from dust and dirt. But researchers at the University of Rochester in New York State -- adding to a growing body of evidence revising our conventional views of vision – have discovered that blinking plays a key role in processing visual information

Prof. Michele Rucci in the brain and cognitive sciences department and colleagues have just published their findings in the Proceedings of the National Academy of Sciences under the title "Eye blinks as a visual processing stage."

Since blinks prevent an image of the external scene from forming on the retina, it's a peculiar quirk of evolution that we spend so much time in this seemingly vulnerable state, "by modulating the visual input to the retina, blinks effectively reformat visual information.

This yields luminance signals that differ drastically from those normally experienced when we look at a point in the scene," explained Rucci who with his colleagues tracked eye movements in human observers and combined this data with computer models and spectral analysis.

They analyzed the various frequencies in visual stimuli to study how blinking affects what the eyes see compared to when the eyelids are closed.

First, they measured how sensitive people are at perceiving different types of stimuli like patterns at different levels of details.

How sensitive are people in perceiving different types of stimuli?

They found that when people blink, they become better at noticing big, gradually changing patterns – blinking supplies information to the brain about the overall big picture of a visual scene.

The results show that when we blink, the rapid motion of the eyelid alters the light patterns that are effective in stimulating the retina.

This creates a different kind of visual signal for our brain compared to when...