For years now, I've had a habit of falling asleep on the sofa around 9:30pm.

The sleep comes on like a wave; it's closer to disappearing into unconsciousness.

I awake about an hour later, and then out of a confused impulse to wreak revenge on myself for falling asleep too early, I proceed to stay up for another hour or two.

I told my doctor about it, and her response to me was: "Do you know about sleep hygiene?"

I didn't. The words "sleep" and "hygiene" in combination only evoked images of dirty bedsheets.

The doctor's prescription for this was: