She was wide awake and it was nearly two in the morning. When asked if everything was alright, she said, Yes. Asked why she couldnt get to sleep she said, I dont know. Neuroscientist Russell Foster of Oxford might suggest she was exhibiting a throwback to the bi-modal sleep pattern. Research suggests we used to sleep in two segments with a period of wakefulness in-between.

A. Roger Ekirch, historian at Virginia Tech, uncovered our segmented sleep history in his 2005 book At Days Close: A Night in Times Past. Theres very little direct scientific research on sleep done before the 20th century, so Ekirch spent years going through early literature, court records, diaries, and medical records to find out how we slumbered. He found over 500 references to first and second sleep going all the way back to Homers Odyssey. Its not just the number of referencesit is the way they refer to it as if it was common knowledge, Ekirch tells BBC.

He knew this, even in the horror with which he started from his first sleep, and threw up the window to dispel it by the presence of some object, beyond the room, which had not been, as it were, the witness of his dream. Charles Dickens, Barnaby Rudge (1840)

Heres a suggestion for dealing with depression from English ballad Old Robin of Portingale:

And at the wakening of your first sleepe/You shall have a hott drinke made/And at the wakening of your next sleepe/Your sorrowes will have a slake.

Two-part sleep was practiced into the 20th century by people in Central America and Brazil and is still practiced in areas of Nigeria.

night street
(Photo: Alex Berger)

Night split in half