From the effect of alcohol to its ability to enhance problem-solving, a report from The Huffington Post details seven interesting facts about REM sleep.

The mysterious phase of deep sleep when our most vivid dreams occur has long fascinated scientists and artists. But it wasn’t until the 1950s that sleep period — also known as rapid eye movement, or REM, sleep — was actually discovered and documented in a lab.

You’ve certainly heard the term REM before, but do you really know what it is — and what’s going on in your brain during this critical time?

During a typical night’s sleep, the brain goes back and forth between REM and non-REM sleep roughly every 90 minutes to two hours, with each cycle lasting anywhere from 10 minutes to an hour. The first REM cycle is generally the shortest of the night, and starts at least an hour and a half after you hit the hay.

As the name would indicate, it’s common for your eyes to rapidly move around in your head during REM sleep. Your heart rate and breathing quicken as well. But there’s much more to REM than than these small physical changes.

Read the full story at www.huffingtonpost.com