Joan Didion: “I write entirely to find out what I’m thinking, what I’m looking at, what I see and what it means. What I want and what I fear. Why did the oil refineries around Carquinez Straits seem sinister to me in the summer of 1956? Why have the night lights in the bevatron burned in my mind for twenty years? What is going on in these pictures in my mind?”
Check this out too: http://www.nytimes.com/2014/06/19/science/researching-the-brain-of-writers.html?_r=0
But writing hurts! Why are positive things painful? Struggle uncomfortable? Because change requires effort, which is energy expended and evolutionarily speaking, the conservation of energy has survival benefits, and so sloth is rewarded? Don’t be a sloth. Your brain needs you. Get on that mental hamster wheel called writing, and churn till you burn.