Language Point 24

Shocked awake by the sound, he would immediately sketch the images seen in his mind in that fertile world of semi-sleep. (Para. 9)

Meaning: The sound woke him up, and then immediately he made a quick drawing of the images in his mind. He had the images when he was almost asleep, which is a good source of creative ideas.

"Awake" is an adjective here; it is not a verb. In Paragraph 7 we have the same word used as a verb in "But scarcely did I awake when away flew the tune and I could not recall any part of it.".

"Shocked awake by the sound" is a past participle phrase placed at the beginning of the sentence. Other examples of similar structure:

Moved by their speech, we did not know what to say.

他们的话使我们很感动，我们不知说什么才好。

Encouraged by his example, hundreds of others began to work again.

在他的带动下，其他数以百计的人也开始工作了。