THE HUMAN EYEHow Do We See?

Black and White Tights Dance

If you stare at the following picture long enough,you should see a giraffe...

Gotcha! But the rest of these optical illusions are on the level.

The famous "Stroop Effect" is named after J. Ridley Stroop who discovered this strange phenomenon in the 1930s. Here is your job: name the colors of the following words. Do NOT read the words... rather, say the color of the words. For example, if the word "BLUE" is printed in a red color, you should say "RED". Say the colors as fast as you can. It is not as easy as you might think!Why?The words themselves have a strong influence over your ability to say the color. The interference between the different information (what the words say and the color of the words) your brain receives causes a problem. There are two theories that may explain the Stroop effect:Speed of Processing Theory: the interference occurs because words are read faster than colors are named.Selective Attention Theory: the interference occurs because naming colors requires more attention than reading words.

More experiments to try:Turn the words upside down or rotate them 90 degrees.

Turn the words "inside out."Use non-color words such as "dog" or "house."Use nonsense words such as "kiw" or "thoz."

Compare long words to short words.Use emotional words such as "sad" or "happy" or "depressed" or "angry."

Color only half of the word or color only the first and last letter of each word.

What do you see?

If your eyes follow the movement of the rotating pink dot, the dots will remain only one color, pink. What happens if you stare at the black plus?

What does this say?

What does this say?

What does this say?

Can you find a man's face among the beans? Some say that if you find the man in 3 seconds or less, the right half of your brain may be more well developed than most.

This picture is NOT animated!

Neither is this one.

Or this one.

Or this one.

And here is another type of illusion.Count the people in the picture below.

After they shift, count them again!

Looking up, or looking down?

Can you count the black dots?

Are the horizontal lines parallel, or do they slope?

How many legs does the elephant have?

Stare at the black dot...after awhile, the gray haze around it will appear to shrink.

Man playing a horn?Or woman's face?

A rabbit, looking right?Or a duck, looking left?

A skull? Or a woman looking into a vanity mirror?

A Native American profile? Or an Eskimo entering a cave?

One face? Or two profiles facing each other?

Which direction is she spinning?

Is the book face-down?Or face-up?

Do you see one man in this picture...or several people?

If you look very carefully, you'll find 9 different faces in the picture; the 9th belongs to a dog.

Which of the figures in the picture do you think would measure the tallest with a ruler?

What do you see?

What do you see?

Which of the MIDDLE circles looks bigger, the one on the left, or the one on the right? Wait, look again!

How many horses can

you find in this picture?

You should see 7

Look at the middle column...where does

it end?

Is this woman old...or young?

This is called an "impossible object", which means that it's impossible to build. But drawing it is not impossible, as you see in the image.

How many human faces can you find in this picture?There are 11

Focus on the dot in the center, and move your head forwards and backwards.

What happens?

Two elderly faces, or a larger scene?

Faces or places?

What do you see?

What do you see?

What do you see?

Where does the puzzle begin and end?

Perpetually ascending staircase...how can the man go up all the time

and come back to the same place over and over?