Sleep Debt & The Biological Clock


Just as you can run up debt on your credit cards, you can borrow too much wakefulness from your brain. Learn how and when it gets "paid back," and also why, even after pulling an "all-nighter," you may find yourself unable to fall asleep at certain times of the day.


Podcast Lecture: The Somniloquy, Episode 4



Dement, The Promise of Sleep: Ch. 3-4

Lavie, The Enchanted World of Sleep: Ch. 5



1. What are some of the consequences of sleep debt?

2. Why can sleep-deprived individuals still feel alert during the day?

3. What were the results of the Naval sleep deprivation study and the Thomas Wehr study?

4. Explain jet lag in terms of the biological clock and the sleep drive.



Home Multiple Sleep Latency Test (MSLT): How much sleep debt do you have? You can approximate the MSLT that Dement describes in chapter 3. He describes this home method on p. 338-339. Lie down in a darkened room. Place one arm over the edge of the bed or couch. In that hand you should hold a metal spoon over a plate on the floor. You want it to be something that will make a noise loud enough to wake you up. Write down the time, and then close your eyes. Set an alarm for 20 minutes. If you do fall asleep, your hand will relax and release the spoon. Write down the time that this wakes you up. That's how long it took you to fall asleep. Repeat the test at different times of the day, over a couple of days. Are your numbers consistent? When are you most alert? Most drowsy? Check your results against the sleep latency chart on p. 340 of Dement.