What is now called functional shift or word-class conversion ... when one part of speech is suddenly transformed into another with a different function but hardly any change of form. It sounds dull but in performance is almost electrically exciting in its sudden simple reach for a word. For example: an adjective is made a verb when in The Winter's Tale heavy thoughts are said to 'thick my blood'. A pronoun is made into a noun when Olivia in Twelfth Night is called 'the cruellest she alive'. Prospero turns adverb to noun when he speaks so wonderfully of 'the dark backward' of past time; Edgar turns noun to verb when he makes the link with Lear: 'He childed as I fathered.'
Subjects were wired up to an electroencephalogram, and read versions of a line from Coriolanus (hurrah!):
This old man loved me above the measure of a father, nay, godded me indeed
'Godded' is the example of enallage, and in the variations it was replaced with words which were correct ('he deified me') or nonsensical (eg 'he charcoaled me'). It was found that 'godded' alone triggered heightened neural activity - as the brain attempted to process the 'incorrect' word, but did not cease to engage with it (as it did when processing a word which made no sense at all).
the P600 surge means that the brain was primed to look out for more difficulty, to work at a higher level, whilst still accepting that, fundamentally, sense was being made. In other words, while the Shakespearian functional shift was semantically integrated with ease, it triggered a syntactic re-evaluation process likely to raise attention and extra emergent consciousness, and giving more power and sheer life to the sentence as a whole.
My feeling is that this is a real phenomenon, which you or I already understand intuitively. Interesting writing is challenging enough to keep readers on their toes, but still allows them to brain what is going on. Enallage is striking example.
Surreal or nonsense writing takes it a step further, but to my mind that only works in small doses and with a strong scaffolding (for instance a familiar form like a limerick) to keep the mind engaged.
Conversely much of the writing I have to do at work is grammatically smooth, unchallenging, designed to soothe and lull.