Page 29 - (DK) How to be a GENIUS?

Ouch!
If you move your eyes around this pattern, called
d
the Ouchi illusion, the circle in the middle seems to
move or separate from the rrectangular background,
and even hovers in front of itt. This illusion is not fully
understood, but it probably arises from the brain
a
being unsure of where the circle ends when you
i
are not looking directly at it.

Jumping goldfish
Stare at the pink dot in the centre of the goldfish’s head for 15 seconds
and then look at the black dot in the empty bowl. You should see the
goldfish in its new home. This happens because an impression of the
goldfish, called an afterimage, is still left on the back of your eye.

Seeing spots
This picture is called a scintillating grid because when
you look at it, dark spots seem to flash (scintillate) in
the intersections between the squares. The reason for
this is yet to be explained, but if you tilt your head to Color contrasts
either side, it seems to lessen the effect. Which of these green crosses is lighter? Most people would
say the cross on the right. It might seem strange, but there is
actually no difference between them. This illusion is known as
simultaneous contrast, and it shows that the way we perceive
colors is based on their surroundings.

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