A very nice piece of trivia that i enjoyed. The actual article is short and to the point. The following excerpt explains enough.

Humans blink every four seconds, on average. How come they never notice? University College London scientists have solved the riddle. When the eyes shut, even for a fraction of a second, the visual system of the brain shuts down too. So you cannot know that you are fleetingly in the dark, they report in Current Biology. Read moreā€¦