Russell Foster is a circadian neuroscientist: He studies the sleep cycles of the brain. And he asks: What do we know about sleep? Not a lot, it turns out, for something we do with one-third of our lives. In this talk, Foster shares three popular theories about why we sleep, busts some myths about how much sleep we need at different ages -- and h...

Wendy Troxel specializes in behavioral treatments for insomnia and other sleep disorders.

Sleep is your life-support system and Mother Nature's best effort yet at immortality, says sleep scientist Matt Walker. In this deep dive into the science of slumber, Walker shares the wonderfully good things that happen when you get sleep -- and the alarmingly bad things that happen when you don't, for both your brain and body. Learn more about...

Far better than counting sheep, these talks on the importance of sleep may well help you get your zzzzs tonight.

In this short talk, Arianna Huffington shares a small idea that can awaken much bigger ones: the power of a good night's sleep. Instead of bragging about our sleep deficits, she urges us to shut our eyes and see the big picture: We can sleep our way to increased productivity and happiness -- and smarter decision-making.

Imagine you're fast asleep and then suddenly awake. You want to move but can't, as if someone is sitting on your chest. And you can't even scream! This is sleep paralysis, a creepy but common phenomenon caused by an overlap in REM sleep and waking stages. Ami Angelowicz describes just how pervasive (but harmless) it is and introduces a cast of c...

In the United States, it's estimated that 30 percent of adults and 66 percent of adolescents are regularly sleep-deprived. This isn't just a minor inconvenience: staying awake can cause serious bodily harm. Claudia Aguirre shows what happens to your body and brain when you skip sleep. [Directed by TED-Ed, narrated by Addison Anderson, music by C...

Can you cram for a test while you sleep? Our intrepid neuroscientists attempt to enhance memory by running experiments on subjects while they sleep. You'll be surprised by the results.

It's 4am, and the big test is in 8 hours. You've been studying for days, but you still don't feel ready. Should you drink another cup of coffee and spend the next few hours cramming? Or should you go to sleep? Shai Marcu defends the latter option, showing how sleep restructures your brain in a way that's crucial for how our memory works.

TED Resident Dan Gartenberg has spent his adult life trying to make seven and a half hours feel like eight hours.

There's nothing quite like a good night's sleep. What if technology could help us get more out of it? Dan Gartenberg is working on tech that stimulates deep sleep, the most regenerative stage which (among other wonderful things) might help us consolidate our memories and form our personalities. Find out more about how playing sounds that mirror ...

In the last century, our sleep patterns have been heavily influenced by artificial light sources. (Think about your smartphone.) In this instructive talk, sleep researcher Dragana Rogulja outlines the damage this does to our health and suggests some ways to combat the problem.

What keeps you up at night? Pondering deep questions? Excitement about a big trip? Stress about unfinished work? What if the very thing keeping you awake was stress about losing sleep? This seemingly unsolvable loop is at the heart of insomnia, the world's most common sleep disorder. So what is insomnia? And is there any way to break the cycle? ...

Teens don't get enough sleep, and it's not because of Snapchat, social lives or hormones -- it's because of public policy, says Wendy Troxel. Drawing from her experience as a sleep researcher, clinician and mother of a teenager, Troxel discusses how early school start times deprive adolescents of sleep during the time of their lives when they ne...

The same resolutions every year -- get more sleep, eat healthier -- we know the drill. Let these talks inspire you to keep with those goals and perhaps add a few more to your list too.

The brain uses a quarter of the body's entire energy supply, yet only accounts for about two percent of the body's mass. So how does this unique organ receive and, perhaps more importantly, rid itself of vital nutrients? New research suggests it has to do with sleep.

In today's world, balancing school, work, kids and more, most of us can only hope for the recommended eight hours of sleep. Examining the science behind our body's internal clock, Jessa Gamble reveals the surprising and substantial program of rest we should be observing.

Silence is a rare commodity these days. There's traffic, construction, air-conditioning, your neighbor's lawnmower ... and all this unwanted sound can have a surprising impact on your health, says noise researcher Mathias Basner. Discover the science behind how noise affects your health and sleep -- and how you can get more of the benefits of th...

Behind the "big house" in pre-Civil War America, there was often another house, smaller, rougher, and filled with chattel slaves, people who lived and died as another person's property. It's a large piece of American history, but it's too often overlooked or even hidden. How can modern people feel the weight of this history? Joseph McGill, found...

Mathias Basner researches the effects of noise on sleep, health, neurobehavioral and cognitive functions and more.

Matt Walker is a brain scientist trying to understand why we sleep.

The new breed of high-tech self-monitors (measuring heartrate, sleep, steps per day) might seem targeted at competitive athletes. But Talithia Williams, a statistician, makes a compelling case that all of us should be measuring and recording simple data about our bodies every day — because our own data can reveal much more than even our doctors ...

Russell Foster studies sleep and its role in our lives, examining how our perception of light influences our sleep-wake rhythms.

Lighting, which is often selected based on installation costs, can actually help us improve how we work, help with jetlag, and even improve our sleep. Researcher Sarah Klein believes we need to think of light differently — not just as illumination, but as a tool for our emotional and biological well-being.

In a moving and madly viral video last year, composer Eric Whitacre led a virtual choir of singers from around the world. He talks through the creative challenges of making music powered by YouTube, and unveils the first 2 minutes of his new work, "Sleep," with a video choir of 2,052. The full piece premiered a few weeks later (yes, on YouTube!).

Natalie Merchant sings from her poetry-inspired album "Leave Your Sleep," which pairs lyrics from poets -- from Gerard Manley Hopkins to a near-forgotten 10-year-old girl in Brooklyn -- with simple melodies and her unmistakable voice. Stay for an encore performance of her hit "Thank You," dedicated to a notable philanthropist in the audience.

Nicole Paris was raised to be a beatboxer -- when she was young, her father, Ed Cage, used to beatbox her to sleep at night. Now the duo is known for their beatbox battles and jam sessions, which mix classic rap beats with electronic dance sounds. Prepare yourself for a bit of a hip-hop history lesson, and enjoy the show.

We have over 600 muscles in our bodies that help bind us together, hold us up, and help us move. Your muscles also need your constant attention, because the way you treat them on a daily basis determines whether they will wither or grow. Jeffrey Siegel illustrates how a good mix of sleep, nutrition and exercise keep your muscles as big and stron...

You've stealthily descended into the darkness of a vampire cave, setting a sequence of mirrors as you go. When the sun reaches the right angle in the sky, a beam of light will ricochet along the mirrors, strike a diffuser, and illuminate the great chamber where the vampires sleep. Can you place the diffuser correctly and flood the lair with sunl...

When Richard J. Berry, the mayor of Albuquerque, saw a man on a street corner holding a cardboard sign that read "Want a job," he decided to take him (and others in his situation) up on it. He and his staff started a citywide initiative to help the homeless by giving them day jobs and a place to sleep -- and the results were incredible. Find out...