Look at the center circles of Diagram A and Diagram B. Which of the centre circles looks larger?
Take a first look and you probably think that the centre circle in Diagram A is smaller than that in Diagram B. In fact, they are exactly the same size.
Then look at the picture on the left. What do you see? A vase? Or two faces? Does the picture change quickly from one to the other again and again? Maybe or maybe not, but you can never see them at the same time.
"What's happening? Is something wrong with my eyes?" You may wonder at what you see. Don't worry. Here is how it goes:
When we look at things, our eyes send messages to our brains and then our brains interpret (解读) the information. However, sometimes our brains interpret the received information in a wrong way. It seems that our eyes are playing a joke on us. This often happens and we call it "visual illusion (视觉错误)"
Movie makers often make use of illusions. They make the objects around actors much smaller or bigger than usual. This makes us believe that the actors are much larger or smaller than they usually are. The movies Jurassic Park and Honey I shrunk the kids just make use of illusions.
a. We look at things with our eyes.
b. Our brains interpret the messages.
c. Our brains tell us what we have seen.
d. Our eyes send messages to our brains.