Down syndrome is the most common genetic cause of mental retardation.

VOA: special.2009.09.09

But when it was all said and done he wasn't blind, he wasn't deaf, didn't lose language, didn't become aphasic, no paralysis, no retardation.

手术完成,他没有失明，没有失聪，没有失去语言能力，没有患失语症，没有麻痹，没有反应迟钝。

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So, it's not really a developmental ... it's not really a developmental delay in the way that it might make sense to think about certain forms of retardation.

孤独症并非发展延迟,不应当把它理解为,某种形式的发育迟缓

耶鲁公开课 - 心理学导论课程节选