Question 1

Why can't you see your own eyes move in a mirror?

Accepted Answer

Because your brain briefly switches off your vision during each rapid eye movement, a process called saccadic suppression. The command to move your eyes also signals the visual system to ignore the resulting blur, so you never perceive the motion, even though a camera or a friend can see it clearly.

Question 2

What is saccadic suppression?

Accepted Answer

Saccadic suppression is the brain's habit of reducing visual sensitivity during the quick jumps your eyes make between fixations. It begins just before the eye moves, filtering out the motion blur that would otherwise smear across your retina hundreds of thousands of times a day.

Question 3

Why does a clock's second hand seem to freeze when you glance at it?

Accepted Answer

This is called chronostasis, or the stopped-clock illusion. After an eye movement, the brain fills the blind interval by stretching the newly seen image backward in time, so the first tick you land on appears to last longer than a normal second.

vision-science

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The Half-Second Your Brain Refuses to Show You