Blinking gives your brain a break
Blink. Blink blink blink. Every minute, we blink our eyes 15 to 20 times. But we only need to blink two to four times a minute for adequate lubrication. So what's happening when we blink those other times? (Blink blink blink)
Source: NBCNews.com: Health
Why the lights don't dim when we blink
Every few seconds, our eyelids automatically shutter and our eyeballs roll back in their sockets. So why doesn't blinking plunge us into intermittent darkness and light? New research shows that the brain works extra hard to stabilize our vision despite our fluttering eyes. Ref. Source 3z.
Why it doesn't get dark when you blink. About every five seconds we close our eyes and blink to moisten them. During this brief moment no light falls on our retina yet it is not constantly dark and we continue to observe a stable picture of our environment. The brain seems to remember the percepts that have just happened. Scientists have now identified a brain area that plays a crucial role in perceptual memory. Source 2y.