How Much Can You Really Learn While You're Asleep?

In Aldous Huxley’s 1932 novel Brave New World, Polish boy Reuben Rabinovitch falls asleep next to a radio receiver. When he wakes up, he is able to recite the entire broadcast. He has no idea what any of it means, though – it’s all in English.

Maria Zarnayova/EPA

Countless articles today claim that you can actually learn music, hone your foreign language skills, or cram for tomorrow’s math exam during sleep. And there is a whole industry trading on this idea. Subliminal message tapes, popularized by self-help guru Tony Robbins, promise to help you stop smoking, lose weight, and even brush up your golf skills and find love – all the while catching some shut eye.

The big sell of “sleep learning” is seductive – how lovely it would be to be productive while we lie like lifeless lumps in bed. But is it actually based on any evidence?

Read the rest at The Guardian here.

Sleep Cycle App: Precise, or Placebo?

Thanks to the Internet, it's the age of self-diagnosis. People like to learn about (and treat) themselves through technology.

Especially when pretty graphs are involved (see fancy screenshot at right).

As a sleep researcher, I was interested in my friends' use of sleep-tracking apps, and I received a pretty positive response when I prompted them for their thoughts:

"I'm a believer."

"When I use it right, I feel less groggy."

The website sleepyti.me and smartphone apps like Sleep Cycle use the average human's sleep pattern to determine the best window of time that you should wake up. The idea is that interrupting the "wrong" sleep cycle stage, such as slow-wave ("deep") sleep or REM (rapid eye movement, when dreaming occurs), results in grogginess upon awakening, as many of us can attest. Sleep researchers call this phenomenon "sleep inertia."

It's such a big deal that, in the sleep laboratory, we as techs are instructed not to wake participants if they're in REM, even if the experimental recording time is over.

So when a friend told me that he only feels refreshed after (according to his sleep-tracking app) eight REM cycles, I got a little skeptical, given the average person will only experience four or five REM periods per night.

What's the verdict on sleep-tracking apps? How do they work, and how accurate are they? Is it all a big scam, or perhaps the placebo effect at work?