《英语流行话题阅读:语境识词4500》73 You Make Mona Lisa Smile

　　Unit 73
You Make Mona Lisa Smile
For nearly 500 years, people have been gazing at Leonardo da Vinci's portrait of the Mona Lisa with puzzle. First she is smiling. Then the smile fades. A moment later the smile returns only to disappear again. What is it with this lady's face? How did the great painter capture such a mysterious expression and haven't other artists copied it? The Italians have a word to explain Mona Lisa's smile: sfumato. It means blurry¹, ambiguous and up to imagination.
But now according to Dr. Livingstone, a Harvard neuroscientist, there is another, more concrete explanation. Mona Lisa's smile comes and goes, because of how the human visual system is designed, not because the expression is ambiguous. Dr. Livingstone is an authority on visual processing, with a special interest in how the eye and brain deal with different levels of contrast and illumination.
In staring at the picture, Dr. Livingstone noticed a kind of flickering² quality. The smile comes and goes as a function of where the viewer's eyes are. The human eye has two distinct regions for seeing the world. A central area, called the fovea, is where people see colors, read fine print, pick out details. The peripheral³ area, surrounding the fovea, is where people see black and white, motion and shadows.
When people look at a face, their eyes spend most of the time focusing on the other person's eyes, thus when a person's center of gaze is on Mona Lisa's eyes, his less accurate peripheral vision is on her mouth. And because peripheral vision is not interested in detail, it readily picks up shadows from Mona Lisa's cheekbones. These shadows suggest and enhance the curvature of a smile. But when the viewer's eyes go directly to Mona Lisa's mouth, his central vision doesn't see the shadows, you'll never be able to catch her smile by looking at her mouth. The flickering quality -- with smile present and smile gone -- occurs as people move their eyes around Mona Lisa's face.
The actress Geena Davis also shows the Mona Lisa effect -- always seeming to be smiling, even when she isn't, because her cheek bones are so prominent.
"I don't mean to take away the mystery of Leonado," Dr. Livingstone said. "He was a genius who captured something from real life that rarely gets noticed in real life. It took the rest of us 500 years to figure out."
It is also not clear why other painters have not copied the effect more often. To make a good counterfeit⁴ Mona Lisa, one would have to paint the mouth by looking away from it. How anyone can do that remains⁵ a mystery.

1 blurry   

adj.模糊的；污脏的，污斑的

参考例句：

• My blurry vision makes it hard to drive. 我的视力有点模糊，使得开起车来相当吃力。 来自《简明英汉词典》
• The lines are pretty blurry at this point. 界线在这个时候是很模糊的。 来自《简明英汉词典》

2 flickering   

adj.闪烁的，摇曳的，一闪一闪的

参考例句：

• The crisp autumn wind is flickering away. 清爽的秋风正在吹拂。
• The lights keep flickering. 灯光忽明忽暗。

3 peripheral   

adj.周边的，外围的

参考例句：

• We dealt with the peripheral aspects of a cost reduction program.我们谈到了降低成本计划的一些外围问题。
• The hotel provides the clerk the service and the peripheral traveling consultation.旅舍提供票务服务和周边旅游咨询。

4 counterfeit   

vt.伪造，仿造；adj.伪造的，假冒的

参考例句：

• It is a crime to counterfeit money.伪造货币是犯罪行为。
• The painting looked old but was a recent counterfeit.这幅画看上去年代久远，实际是最近的一幅赝品。

5 remains   

n.剩余物，残留物；遗体，遗迹

参考例句：

• He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
• The remains of the meal were fed to the dog.残羹剩饭喂狗了。