I'm writing a book about Rust. One phenomenon I've noticed while working on the book is that, after I've been working on a particular passage for a while and I've read it over many times, it becomes hard for me to really "see" the text of the passage clearly, and follow its flow the way a new reader would. The process of revision becomes difficult because it's harder to actually pay attention to the text that I've read so many times before. Subjectively, it's almost as if something in my mind has become saturated, and can't absorb any more.
From a cognitive science or psychological point of view, what's going on here? Is there anything I can do to help me work on my text more effectively?
What you're describing is a well-documented cognitive phenomenon known as textual habituation or perceptual fluency. Essentially, the brain becomes so familiar with the text that it stops processing it deeply. Instead of actively reading each word, your mind starts skimming or filling in gaps based on memory. This mak