Your eyes help you see the world.
But you can't see this dot
No, seriously!
If you close your left eye,
stare at this cross here with your right eye
and slowly move your head towards or away from the screen,
the dot will disappear.
Revealing the exact location of your blind spot.
The cells of the back of your eye
transforms light into signals that are
sent to your brain.
But they are missing right here because
this is where nerves and blood vessels
connect to the eye.
So anything at that point in your vision you can't see;
a.k.a your "blind spot".
If we add a line through the image and you try again,
you'll notice that your brain fills in information
and makes you think the line is continuous
instead of there being a hole in your vision.
You also can't see all twelve of these black dots at once for a similar reason.
Go ahead and try; chances are, you'll only see a fraction
of them at once.
The exact point your eye looks at is focused,
But your peripheral vision isn't great and so your brain
often makes assumptions for whats there.
Because of the consistent grey line pattern
your brain assumes the rest of the image is just like that
and misses the black dots until you look directly at them.
These two rectangles are flashing out of phase with each other, right?
How about now?
For most, the rectangles will now seem to be flashing at the same time
in phase but they aren't at all.
And yet if we move these shapes beside them
just a few pixels you'll begin to
see them out of phase again.
The surrounding area has a direct impact on how you see
and perceive things, even if the result isn't correct.
Not convinced?
Look at these flashing squares.
Except what you might not have seen is that the
middle square isn't flashing at all.
If you remove the outer square we see it for what it is,
a solid colour.
Now try reading the sentence inside it.
Did you catch the extra word?
Your brain doesn't always notice extra mistakes like these
because it doesn't affect the comprehension of the sentence
and your brain would prefer to act quickly rather than be perfectly accurate.
Try staring at the middle dot in this illusion.
When the picture isn't moving the colours are clearly changing quickly
yet when the image starts rotating
the colour change either seems non-existent or much slower.
Our eyes and brain have evolved to see
but our vision makes assumptions based on learning, memory and expectation
and all of these illusions take advantage of this adaptation.
It's an advantage to have rapid information processing
so instead of taking in every bit of detail to be 100% accurate
which would cause a brain overload, your brain makes assumptions.
This faster perception allows for
faster reflexes and faster unconcious and unconcious decisions;
an integral aspect of human nature.
Much like this halo, if you stare at the centre dot long enough
the brain will simply make it disappear.
It makes an assumption the information is unchanging or unimportant and
as a result you can't see it.
Love tricking your brain with illusions?
We've put together a playlist of our favourite ones
that you can watch by clicking the screen.
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