The author Nicholson Baker has written about writing with earplugs:
"I’ve always been helped by sensory deprivation. I used to wear earplugs a lot. Sometimes I would write with my eyes closed. But writing in the early morning is different because you haven’t been able to see anything for hours. I would get up and feel my way around. The only help was the moonlight, if it was a moonlit night. You think differently if you can’t see."
http://www.amazon.com/Howard-Leight-MAX-1-plugs-Uncorded/dp/...
You're welcome.