Something amazing happens when the rest of the world is sleeping. I am glued to my chair. I forget that I ever wanted to do anything but write. The crowded city, the crowded apartment, and the crowded calendar suddenly seem spacious. Three or four hours pass in a moment; I have no idea what time it is, because I never check the clock. If I chose to listen, I could hear the swish of taxis bound for downtown bars or the soft saxophone riffs that drift from a neighbor's window, but nothing gets through. I am suspended in a sensory deprivation tank, and the very lack of sensation is delicious.
Anne Fadiman, At Large and at Small: Familiar Essays
concentration, night, sensory-deprivation, sleeplessness