what I need you to do is stare at the
screen there's gonna be a dot in the
middle of the screen and you're gonna
keep your eyes on that dot before we
hear from our volunteers let's give you
a chance to play along just like before
stare at the dot in the center of this
image are you staring at the dot here's
a tip to make the colors appear for
longer when the image changes to black
and white make sure your eyes remain
focused on the dot
ready here we go
do you see this Castle in full color now
if you move your eyes you'll see it's
actually just a black and white image
pretty wild huh let's see if our
volunteers experienced what you just did
keep your eyes on the dot I just our
color everything is colored the trees
were green and everything that way what
if I was to say that the colors were put
there by your brain they were never on
the screen I won't believe you what if I
was to promise you can promise all you
want I know what I saw
that's crazy are you as surprised as
they are our volunteer Paul says it best
if you're telling me I didn't see color
then where is it coming from that's a
good question how was your brain
painting this black and white picture in
full color when there isn't any color at
all
we've asked Yale psychologist Brian
Scholl the same question
we have millions of photoreceptors in
our eyes that help us to see color
now when you stare at the same color for
a long time the cells that are
responsible for that color they get
tired and they don't respond as strongly
when you stare at this image some of
your photoreceptors like the ones that
handle reddish orange get tired then
when the image flips back to black and
white those tired cells can't pull their
weight and it's the cells for the
complementary colors that are more
active orange and blue are complementary
colors so when the orange tones go away
your brain adds blue to this
black-and-white image the result is that
we experience a vivid sensation of color
even when in this case the colors not
really there
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