身边有这么一些人，看见熟人都会张口喊一句“那谁！”然后盯着人家半天叫不出名字。这世界上还有那么一些人，他们无法辨认别人的容貌，就算是每天相见的熟人，他们也认不出来。如果说前者是一时语塞，后者却是实实在在的一种病症。

Face blindness refers to difficulty recognizing faces or telling faces apart.

脸盲症（face blindness）指难以辨认或分别人的容貌的状况。

New findings from researchers at Harvard and elsewhere suggest that a surprising number of people are face-blind, so bad at recognizing faces that they routinely snub acquaintances and have trouble following movie plots. In extreme cases, they may greet siblings as strangers and struggle to discern which child is theirs at school pick-up time.

来自哈佛及其他地方的研究人员发现，有相当一部分人都患有脸盲症，而且这个数目是惊人的。这些人完全无法辨识脸部容貌，以至于经常对熟人视而不见，看电影时也跟不上情节。在一些极端案例中，他们会把自己的兄弟姐妹误当成陌生人，到学校接孩子时经常无法判断哪个孩子才是自己家的。

The syndrome, known medically as prosopagnosia, was long thought to be a rare neurological curiosity that resulted from brain damage.

这种综合征的医学学名为prosopagnosia，长期以来一直被看作是罕见的神经科奇症，且由脑损伤引起。

Research has begun to suggest that most face-blindness stems from genes, rather than brain injury, and that it is far more widespread than previously suspected, with up to 2 percent of the population affected to some degree.

不过，有研究显示，大部分脸盲症不是脑损伤引起的，而是由基因导致的；另外，其发病规模也远远超出之前的预测，全球人口中有2%的人都患有不同程度的脸盲症。