Hey, Vsauce. Michael here.
And today I've got a brand new episode
of Vsauce Leanback.
You can click this annotation
or the link at the top of the
description to start it and then you can
just lean back
and the autoplay playlist bring the
knowledge right to your brain.
As you already know, it doesn't really
work on mobile phones yet so wait until
you are in a better position to lean back.
In the meantime, let's get saccadic.
No, not psychotic, saccadic,
referring to what is known as
a saccade, the quick
movements that our eyeballs make
when we move from one
object to the other. As you may remember
from a previous Leanback, some animals,
like most birds,
cannot move their eyeballs. And so to look
from one thing to another they have to
move their head really really fast
and to keep the world from being blurry
when their bodies move, they have to keep
their heads completely stationary.
But here's the neat thing about saccades.
When our eyes move,
there's a quick blur between
one destination and the other. And that
blur is completely incomprehensible to
our brain.
So what are visual system does is erase it
from our memory and instead replace that
little fraction of a second that our eye
moved during
with the very next thing we see.
This leads to a really amazing illusion
called
'The Stopped Clock Illusion."
You may have noticed this before
if you've ever been in a room with a
clock with a second hand, like in a
classroom,
darting your eyes back and forth
waiting for class
to be out. Now here is what happens.
Right when you dart your eyes to the clock,
that very first second, that very first
movement of the second hand
that happens when your eyes reach it
seems longer
than every other second afterwards.
Look away from the clock
and then look.
And that first second will seem to linger,
as if time itself has stopped.
The reason for that
is that your brain replaces the time
it took for your eye to go from here
to the clock with an image of the
first thing you saw, which was the second-hand.
And so, that little fraction of a
second of time is added
to length of time it takes the second-hand to
move. What's really mind-blowing about
this entire
effect is that it happens all the time.
All day,
as you look around the world from one
point to another, that little fraction of
a second
that your eyeball was moving is lost
and your brain just replaces it with the very
next thing
that you see. Now, it might just be
a tiny tiny amount of time,
but over the course of an entire day
those little fraction of a second
add up to almost 40 minutes.
40 minutes of everyday that you're awake
are lost
because our eyeballs move.
And as always,
thanks for watching.
So what are you waiting for,
click here to start the Leanback or click
the link at the top of this
video's description.
You know what? I totally
never say this... Yeah, I'm totally heterosexual, but..
You are really attractive!
