The brain benefits of deep sleep -- and how to get more of it | Dan Gartenberg

Mastering the Art of Sleep: Finding the Perfect Balance of Deep, Light, and REM Sleep

REM Sleep - How Much Sleep Do You Need

What's REM Sleep - How Much Do You Need?

How much sleep do you really need? | Sleeping with Science, a TED series

Mayo Clinic Minute: What are the stages of sleep?

A walk through the stages of sleep | Sleeping with Science, a TED series

2-Minute Neuroscience: Stages of Sleep

REM Sleep Disorder

Stages of Sleep - non-REM, REM, Sleep Studies

"Get Quality and Sufficiently Long Deep Sleep" by Dr. Andrew Huberman

Is Too Much REM Sleep An Issue? | Cabral Concept 2336

Are you Getting Enough Deep Sleep?

Too much REM sleep: why do depressed people wake up exhausted? | Human Givens

Are naps actually good for us? | Sleeping with Science

Study helps explain sleep problems in the elderly

Why you're still tired after getting 8 hours of sleep

How lack of sleep affects health and tips for a good night's rest

The Danger of Sleeping Too Much

The surprising health benefits of dreaming | Sleeping with Science