Illusions and Other Visual Defects

CITA 6016

Food Sensory Analysis

University of Puerto Rico

Food Science & Technology

Visual Illusions

Brain misinterpretation of the presented visual information

See http://www.michaelbach.de/ot/ for a full tour of examples

Count the black dots!

Are the wheels turning?

Which side is up?

Which end is closer to you?

Parallel or sloping lines?

How many legs?

Look at the dot. Where’s the haze?

Focus on the dot and move.

Are purple lines straight?

Which center is larger?

Ghostly dots?

Man or Liar?

How many tines in the fork?(two, but can you see three?)

More examples

What does this say? Look again.

Are the sides of the square curved or straight? Check with a straight edge.

More examples

How many colors?(two)

Are the diagonal lines parallel?

(yes)

Do you see a man playing a sax or a woman in shadow?

Can you see both an old lady and a

young lady?

Right or Left Brain

The brain is a great parallel processor for visual information.

Identifies differences Fill in blanks

…but can get in trouble

Identifies differences

Fill in blanks

Aoccdrnig to a rscheearch at an Elingsh

uinervtisy, it deosn't mttaer in waht oredr the

ltteers in a wrod are, the olny iprmoetnt tihng

is taht frist and lsat ltteer is at the rghit pclae.

The rset can be a toatl mses and you can

sitll raed it wouthit porbelm. Tihs is bcuseae

we do not raed ervey lteter by it slef but the

wrod as a wlohe

Internal fight

Blindness

Some people cannot see some colors

… can you?

NormalColorVision

Red/GreenColorBlind

Blue/YellowColorBlind

Blindness

NormalColorVision

Red/GreenColorBlind

Blue/YellowColorBlind

Blindness

NormalColorVision

Red/GreenColorBlind

Blindness

What numbers do you see?

What numbers do you see?

What numbers do you see?

What numbers do you see?

What shapes do you see?

What shapes do you see?

What shapes do you see?

What shapes do you see?

Carry Over Effects

Vision sensors saturate and keep “memory” of the previously seen image with contrasting colors

Look at the four dots for 10 seconds.

What do you see?

Try this one…

What do you see?

…and this one?

What do you see?

…and this one?

What do you see?

Conclusion

Don’t believe everything you see Be aware that panelists are human too and

may unadvertedly make mistakes