The average adult spends more than 220,000 hours - or roughly 25 years - in bed sleeping. That's one-third of your life spent in slumber! But what exactly is sleep? Why do you spend so much of your time doing it? And what happens to your brain and body if you don't get a full night's rest? In what could be our most ambitious Brain Games experiment ever, we keep three volunteers awake for 36 hours in order to test the effects of sleep deprivation on human performance. Join them in our special Sleep Lab, and play along as we put them through a battery of physical and mental tests. Will their scores hold up, or will the lack of z's cause them to crash? You're going to want to stay up for this special episode of Brain Games.

Streaming video file encoded with permission for digital streaming by Infobase on September 04, 2015.

Sleep: Introduction --(1:16) -- Sleep Deprivation Experiment -- (2:17) -- Baseline Testing -- (3:54) -- Driver Fatigue -- (3:10) -- Sleep-Deprived State -- (2:21) -- Microsleep -- (2:12) -- Evidence of Sleepiness -- (2:30) -- Sleep Testing -- (4:52) -- Illusion Game -- (Credits) (1:26).