Oh, this is weird, I've no idea how long I've slept for now because I've slept twice in the night.
So let me have a little guess now what time it is.
I can't really know, can I?
It could be six in the morning. It could be one in the afternoon.
I've no idea how far through this experiment we are. But I don't really.
There is no real gauge of time.
That's why we need the sun, or a clock.
For university lecturer Brain Keenan, the lack of daylight had a profound effect
when he was taken hostage in Beirut and held in a windowless cellar.
I reckon I was in the dark about seven or eight months, I can't be sure.
It was very hard to tell time.
There was no daylight at all so I slept fitfully.
I didn't go to sleep and sleep for the eight hours. I catnapped.
I slept for ten minutes, woke, stayed awake for a couple of hours,
went to sleep for an hour or maybe three hours. It was that kind of random pattern.