面孔失認(rèn)癥是一種神經(jīng)心理性疾病,表現(xiàn)為對(duì)熟悉面孔的識(shí)別能力降低或喪失。一般來講,面孔失認(rèn)癥病人不能再認(rèn)出以往熟悉的知名人士及親朋好友的面孔 。雖然面孔失認(rèn)癥病人在看一個(gè)面孔時(shí),他們?nèi)钥擅枋雒婵椎奶卣鳎撬型怙@意義上的識(shí)別卻不能進(jìn)行或功能下降,對(duì)非常熟悉人的面孔也沒有任何的熟悉感 。但一些病人解釋面孔表情的能力或者匹配不熟悉面孔的能力仍相當(dāng)完好。除了識(shí)別面孔外,識(shí)別其它物體的能力可能也相當(dāng)完好,并且很多面孔失認(rèn)癥病人閱讀也毫無困難。幼年時(shí)因腦損傷發(fā)生的病例不能識(shí)別任何面孔,盡管如此,他們?nèi)钥梢詫W(xué)會(huì)閱讀 ;這個(gè)現(xiàn)象說明了閱讀和面孔識(shí)別實(shí)際上屬不同類型的視覺分析。面孔失認(rèn)癥常伴隨的一般功能障礙包括左上視野缺陷、全色盲和地形判斷的功能異常(topo-graphical disorders)。病人所表現(xiàn)出的障礙是不能將熟悉面孔再認(rèn)出來,在社交活動(dòng)及工作中常常遇到一些問題,多數(shù)病人依賴其它線索來彌補(bǔ)面孔失認(rèn)方面的缺陷 ,根據(jù)個(gè)體的其他特征,如聲音、發(fā)型、服飾、步態(tài)等將其鑒別出來。
You wake up one morning to find a strange man standing in your kitchen; worse than that, he seems to have made himself completely at home.
Someone’s child is sitting in the living room watching television, on which somebody or other is giving a speech while standing next to a bust of some old guy. Who are these people? And where’s your family?
If you suffered from the neurological disorder called “facial agnosia,” a twilight-zone style experience of this sort might be a reality. Facial agnosia typically occurs to people who have received damage to the right hemisphere of the brain due to stroke or injury. People with facial agnosia lose the ability to recognize even the most familiar faces: in this case a husband and daughter, the president of the United States and a bust of Abraham Lincoln. In severe cases an examining physician will be able to hold up a photograph of him or herself and, seated in front of the patient with facial agnosia, ask if they recognize this person — to no avail.
What’s especially interesting to researchers about this condition is its specificity. Visual ability itself is not damaged, and the person with facial agnosia can still recognize anything else — except a face. Indeed, they can still describe faces very accurately, but only in the way one describes an object: “He needs a shave. He has droopy eyes. He has a small scar,” but never “Wait a minute — this is my high school yearbook picture.” Facial agnosia strongly suggests the existence of a mechanism in the brain devoted specifically to recognizing individuals we’ve seen before, a mechanism thought to exist in many other animals and even some insects.
譯文:
你一早醒來,發(fā)現(xiàn)你的廚房里站著一個(gè)陌生人。更糟糕的是,他似乎像在自己家一樣隨意。
不知誰家的孩子正坐在客廳看電視,電視里播放著一個(gè)人站在一位老者的半身像旁高聲演講著。這些人是誰?你的家人去哪兒了?
如果你患上了一種腦神經(jīng)失調(diào)的面孔失認(rèn)癥,那么像這樣模糊不清的“過渡”式的經(jīng)歷或許是一個(gè)事實(shí)。面孔失認(rèn)癥常出現(xiàn)于人們大腦的右半球被打擊或損傷后?;加忻婵资дJ(rèn)癥的人會(huì)失去辨認(rèn)面孔的能力,即使是最熟悉的人也不列外:比如丈夫或者女兒,美國的總統(tǒng)或者亞伯拉罕林肯的半身像。在嚴(yán)重的情況下,檢查的醫(yī)生會(huì)拿著一張自己的照片,坐在面孔失認(rèn)癥患者的前面,詢問他們是否認(rèn)識(shí)這個(gè)人,但是完全不起作用。
對(duì)于研究者來說這種情況最有趣的就是它的特殊性。視覺能力本身沒有損壞,面孔失認(rèn)癥患者仍然能夠辨別別的事物-除了臉。事實(shí)上,他們?nèi)匀豢梢苑浅?zhǔn)確地描述面孔,但是就像描述物體似的。“他需要刮胡子,他有雙下垂的眼睛,他有一個(gè)小疤痕”。但是從不會(huì)聽到“等一下-這是我高中的畢業(yè)照。”面孔失認(rèn)癥患者暗示了人類大腦里存在著一種專門用于辨認(rèn)見過的人的機(jī)制,這種機(jī)制也被認(rèn)為存在于別的動(dòng)物甚至一些昆蟲中。