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第25章 Appearance Can Be Recognized Like Words

Although they are dramatically different, words and faces are both recognized by parts, not by wholes①.

It has been suggested that faces and words are recognized differently, that faces are identified by wholes, whereas② words and other objects are identified by parts.

However, the neuroscientists find individuals③ use letters to recognize words and facial features to recognize faces.

To reach this finding, experiments were performed in which observers were asked to focus on a black dot, to the right of which was a letter. To the left of the dot was a three-letter word in which the letter to the right was in the middle of that word. The visual experiments also involved manipulated④ faces and facial features. In this case, observers would focus on a black dot. To the dot’s right were lips that were fat or thin, or smiling or frowning. To the left of the dot was an entire face.

When the words to the left were spaced normally and the face was of normal proportions, subjects had a great deal of difficulty identifying out of their peripheral⑤ vision the letter and the characteristics of the lips. Pelli concludes that context hinders identification and crowds what is to be identified.

In a second experiment, the observers were presented with a context that proved to make recognition easier. Where letter identification was involved, the letters comprising⑥ the word to the left of the dot were spread out. When faces were involved, the facial features similarly were spread apart. In this experiment, subjects found naming the letter and recognizing the type of lips to the dot’s right far easier. In this case, the neuroscientists note, to recognize a word or face, each letter or facial feature must be isolated from the rest.

These measures appear to be identifying what kind of computation is performed by the brain in doing this. The brainis recognizing these objects by parts, not as wholes. Our visual system recognizes “bite-sized⑦ pieces” of our world, and our brain assembles them into the perceptual objects that constitute our environment.

① wholen. 全部,全体\[the S\]\[(+of)\]

② whereasconj. 反之;却;而

③ individualn. 个人;个体

④ manipulatev. (熟练地)操作,运用

⑤ peripheraladj. [解]体表的;(神经)末梢的

⑥ comprisev. 包含,包括

⑦ bite-sizedadj. 一口可以吃下的

容貌像文字一样被识别认知

尽管文字和人们的容貌两者看起来是如此不同,但是科学家们发现,容貌和文字一样,都通过部分被识别认知的,而非被整体识别认知的。

人们曾经认为,人的容貌和文字是通过不同的方式被认知的,其中容貌是通过整体认知而文字和其它物体则是通过部分认知被人们识别的。然而神经科学家通过研究发现,人们是通过字母来识别文字的,同时也是通过面部特征来识别一个人的容貌。

在试验过程中,研究者要求参与者把注意力集中在一个黑色圆点上,在黑点的右边是一个字母,黑点的左边是一个由3个字母组成的词语,中间那个字母和黑点右边的字母相同。同样地,在第二组试验中,参与者也被要求把注意力集中在一个黑点上,黑点右边是或薄或厚或微笑或生气的嘴唇,而黑点左边是一整张面孔。

结果发现,当组成黑点左边单词的字母间隔正常,或一整张面孔呈标准比例时,参与调查者很难从他们的周围视觉对字母或是嘴唇的特征进行识别。神经学家由此得出结论,是背景环境阻碍了识别过程,同时影响了要被识别的东西。

第二个试验中,研究者提供给参与者一个被证实更容易认知的背景环境。黑点左边组成单词的字母被展开,人的容貌特征也相应地被分开。在这次试验过程中,参与者发现认清黑点右边的字母或是辨别嘴唇的特征就变得非常容易了。对此,神经学家们表示,要想识别一个单词或是一个人的容貌,组成单词的每个字母或是面部特征都要与其它字母或特征分隔开。人的大脑就是部分地来识别这些物体的,而并非全部。我们的视觉系统认知我们世界“非常小的部分”,而我们的大脑将它们集合成构成我们环境的感知物体。