In "Flowers for Algernon" by Daniel Keyes, the protagonist Charlie Gordon is a special needs man who agrees to undergo an experiment that is meant to increase his intelligence. The narrative is composed of Charlie's progress reports, which at first reflects his low intelligence through limited vocabulary and incorrect writing. The author's language changes according to Charlie's mental progression; his grammar and spelling improve significantly, and his vocabulary increases.
I believe you have to write up your own. I hope this comes in handy^-^
