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

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.

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.

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.

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.

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

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.

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 ...

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...

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? ...

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...

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

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.

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 ...

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.

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...

Over our lifetimes, our bodies undergo a series of extraordinary metamorphoses: we grow, experience puberty, and many of us reproduce. Behind the scenes, the endocrine system works constantly to orchestrate these changes. Emma Bryce explains how this system regulates everything from your sleep to the rhythm of your beating heart, exerting its in...

If the brain takes care of the body, how does the brain take care of itself? Find out the remarkable things the brain can do to stay in tiptop shape.

Arianna Huffington's small idea to help you unlock your big ideas: Sleep more. "I learned the hard way the value of sleep," said Arianna Huffington at TEDWomen in 2010. "Two and a half years ago, I fainted from exhaustion, and I hit my head on my desk." (Watch: Arianna Huffington: How to succeed? Get more sleep.) Since then, the media mogul has...

Spellbinding, stimulating, seductive … science? Here, the 10 most-watched science talks on TED.com. See why.

Worn out? Exhausted? Bleary-eyed? If you need a little something to ease your frustration and get you back in the spirit, this collection of talks should help.

Neuroscientist Russell Foster opens a session of TEDGlobal all about ... us, asking the question: Why do we sleep? Thirty-six percent of our lives are spent asleep, which means, if you live to 90, you'll have slept for 32 years. But we don't appreciate sleep enough, says Foster. He quotes Thomas Edison -- "Sleep is a criminal waste of time, ...