Page 30 - (DK) How to be a GENIUS?

HOW YOU Binocular vision

Each eye sees a slightly different image of the world. Try closing
one eye and framing a distant object with your hands. Then open
SEE that eye and close the other. You will find that your hands are
framing a different view. The images below show the different
seen

eye
each
by

the
same
setting

views of the same setting seen by each eye The left eye can
views

of
.

eye
ca
n

The

eft
l
see the palm trees behind the boat, while the right eye sees the
flowering trees. You might expect this to confuse your brain,
but it combines the images to create a 3-D view.
Your eyes turn visual images intoo an
electronic code that can be processed
s
and stored in your brain. It is this mental
processing that determines howw you
see the world. Without it, you could
not make sense of all the shapes
s
and colors. Your brain also
responds to some visual effects
by translating them into other
types of information. This enables
e
you to judge things like depth,
shape, and distance.

Perspective
A th
Another way your brain judges distance is by decoding perspective.
Parallax This is the effect you get when you look up at a tall building and
If you close one eye and look at a scene the walls seem to lean toward one another—even though you know
without moving your head, it looks flat they are vertical. Your brain makes an automatic calculation based
like a picture. But if you move your head on this knowledge and turns it into a perception of height.
from side to side, you get an impression
of depth. This is because objects that are
closer to your eye seem to move more
than objects that are farther away, and
your brain translates the difference into
a perception of depth. This parallax effect
is obvious if you look out of the side
window of a moving car—nearby objects
like these pillars zip past, but distant
objects like the trees move hardly at all.

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(c) 2011 Dorling Kindersley. All Rights Reserved.
(c) 2011 Dorling Kindersley. All Rights Reserved.