For a really great interactive online chart exploring the different stages of sleep, visit: http://www.pbs.org/wgbh/nova/body/sleep-memory.html  and click on “LAUNCH INTERACTIVE”.

What happens in your brain as you cycle through the various stages of sleep, and how does this activity affect learning and memory? See what scientists are learning about REM (rapid-eye movement) sleep and other phases, and explore recent research linking sleep—and sleep deprivation—to different types of memories.

Explore the stages of a good night’s sleep and the research linking sleep to memory.