第二章结尾的时候，作者留了个问题：刻意练习到底让我们的大脑发生了什么样的变化呢？

What exactly is being changed in the brain with deliberate practice? The main thing that sets experts apart from the rest of us is that their years of practice have changed the neural circuitry in their brains to produce highly specialized mental representations, which in turn make possible the incredible memory, pattern recognition, problem solving, and other sorts of advanced abilities needed to excel in their particular specialties. 

专家之所以优秀是因为年复一年的刻意练习（deliberate practice），改变了他们的大脑神经回路，产生了高度专业化的心理表征（mental representations）。心理表征有助于短时记忆，规律识别，问题解决等能力的增强与提升，无形中让专家在特定领域越来越优秀。这就像是一种良性的循环。

A mental representation is a mental structure that corresponds to an object, an idea, a collection of information, or anything else, concrete or abstract, that the brain is thinking about. 

所谓的心理表征，是一种与我们大脑正在思考的某个物体、某个观点、某些信息或者其他任何事物（具体或抽象）相对应的心理结构。

最直观的一个例子就是视觉图像（visual image），比如当我们听到有人提起 “蒙娜丽莎” 的时候，我们的脑海中会不由自主的出现她的画像，而这个画像就是蒙娜丽莎在我们脑海中的心理表征。

只是，我们每个人在脑海中呈现的心理表征内容是不一样的，正如 “一百个观众就会有一百个哈姆雷特” 一样，同一概念同一事物，会因为我们的心理表征的质与量不同，而导致输出结果不同，这便造成了专家与普通人之间的差距。

Experts see the forest when everyone else sees only trees.

所谓的专家，总能在自己所长的领域里找到规律，“窥一斑而见全豹”，从而创建出更高效的心理表征；不会像绝大多数人一样局限于 “只见树木，不见森林”的小格局。

就拿阅读这件事来说，参加读书会的小伙伴们读的是同一本书，可是相同的内容折射回各自的脑海后呈现出来的心理表征就有很大的差异性。有的小伙伴可以很快很有效率的阅读完，吸收知识点后，与自己脑海中其他的相关信息融会贯通，重新整合并输出一份很高质量的读书笔记；而之于我，目前尚无法达到这种高度，常常是看的时候十分明白，看完要写笔记的时候就一脸懵逼。我想这主要还是因为以前太缺乏这种读书写笔记的刻意练习吧。

At first glance, the way that so many grandmasters develop the ability to play blindfold chess might seem nothing more than an artifact, an interesting footnote to the history of chess. But if you look more closely, you find that ...... Furthermore, the same sorts of highly developed mental processes are seen in expert performers in every field......

at first glance, 副词，也可用 at first sight or at first blush，表示“乍一看...初看之下...”的意思，the first time that you look at someone or something, before you noticeany details. 

例句：At first glance, the proposal seems ridiculous.

But if you look more closely, 表示 “但如果细看的话...”.

furthermore，副词，也可用 moreover，表示 “进一步说，此外，而且...” in addition to what has already been said. 

at first glance...but if you look more closely...furthermore...，层层递进，很适合写作用。

These hitters have just a split second to decide whether to swing and, if so, where to reflexes are faster.

a split second, 名词，表示 “一刹那，瞬间”，an extremely short period of time. 形容词是 split-second. 可搭配有：for a split second 有一瞬间；or in a split second 刹那间.

例句：For a split second the two men hesitated.

例句：In that split second Graham knew he had won.

仿造句：It took me a split second to decide that I could drive him a ride.

The more you study a subject, the more detailed your mental representations of it become, and the better you get at assimilating new information.

assimilate,  动词，原文中表示“吸收，消化”，to completely understand and begin to use new ideas, information etc. 

例句：It will take time to assimilate all these facts.

此外，还有 “同化” 的意思，to cause (a person or group) to become part of a different society, country, etc. 常见搭配有：assimilate into

例句：Schools were used to assimilate the children of immigrants.