Study Shows Faces Are Processed Like Words
儘管文字和人們的容貌兩者看起來是如此不同，但是美國紐約大學的科學家們日前發現，容貌和文字一樣，都通過部分被識別認知的，而非被整體識別認知的。
Although they are dramatically different, words and faces are both recognized by parts, according to a study published in February in the Journal of Vision, an online, free access publication of the Association for Research in Vision and Ophthalmology (ARVO).
據美國“每日科學”網站日前報道，人們曾經認為，人的容貌和文字是通過不同的方式被認知的，其中容貌是通過整體認知而文字和其它物體則是通過部分認知被人們識別的。然而，美國紐約大學的3位神經科學家，Marialuisa Martelli、Najib Majaj和丹尼斯·培裡日前通過研究發現，人們是通過字母來識別文字的，同時也是通過面部特徵來識別一個人的容貌。
在試驗過程中，研究者要求參與者把注意力集中在一個黑色圓點上，在黑點的右邊是一個字母，黑點的左邊是一個由3個字母組成的詞語，中間那個字母和黑點右邊的字母相同。同樣地，在第二組試驗中，參與者也被要求把注意力集中在一個黑點上，黑點右邊是或薄或厚或微笑或生氣的嘴脣，而黑點左邊是一整張面孔。
研究發現，當組成黑點左邊單詞的字母間隔正常，或一整張面孔呈標準比例時，參與調查者很難從他們的周圍視覺對字母或是嘴脣的特徵進行識別。培裡由此得出結論，是背景環境阻礙了識別過程，同時影響了要被識別的東西。
在第二個試驗中，研究者提供給參與者一個被證實更容易認知的背景環境。黑點左邊組成單詞的字母被展開，人的容貌特徵也相應地被分開。在這次試驗過程中，參與者發現認清黑點右邊的字母或是辨別嘴脣的'特徵就變得非常容易了。對此，培裡表示，要想識別一個單詞或是一個人的容貌，組成單詞的每個字母或是面部特徵都要與其它字母或特徵分隔開。他說：“人的大腦就是部分地來識別這些物體的，而並非全部。我們的視覺系統認知我們世界"非常小的部分"，而我們的大腦將它們集合成構成我們環境的感知物體。”
Although they are dramatically different, words and faces are both recognized by parts, according to a study published in February in the Journal of Vision, an online, free access publication of the Association for Research in Vision and Ophthalmology (ARVO).
It has been suggested that faces and words are recognized differently, that faces are identified by wholes, whereas words and other objects are identified by parts.
However, Marialuisa Martelli, Najib Majaj, and Denis Pelli, three neuroscientists from New York University, conducted a study that finds individuals 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 manipulated 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 peripheral 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 comprising 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, Pelli notes, 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," says Pelli. The brain, he says, is recognizing these objects by parts, not as wholes. Our visual system recognizes "bite-sized pieces" of our world, and our brain assembles them into the perceptual objects that constitute our environment.
