If you've ever woken up unable to move or talk, you know the feeling can be absolutely terrifying. It is so alarming that it has become the subject of folklore across the world and is often associated with the supernatural. The good news is you're not being attacked by the unknown, what you're experiencing is a medical condition called sleep paralysis.

Dr. Manny Alvarez, senior managing health editor of FoxNews.com, recently received an email from a viewer about this phenomenon:

Q: There have been times when I wake up out of a dream and am not able to move. I am fully conscious and aware of my surroundings but I am completely paralyzed. Is there anything I can do to stop this from happening?

Sleep paralysis is a jarring occurrence that leaves you temporarily paralyzed while being fully conscious. It is often seen in people who have sleep apnea or narcolepsy and can also be found in those who suffer from bipolar disorder and are taking certain medications for conditions like ADHD and substance abuse.

In addition to the helpless feeling that one may have while being cognizant and unable to move, the fear surrounding sleep paralysis is heightened by the fact that it's usually coupled with a feeling of pressure or choking and troubling hallucinations. Visions ranging from home intruders to demons have plagued those who suffer from sleep paralysis.

Sleep paralysis usually occurs during REM (rapid eye movement) sleep, a phase where your "brain is active but your muscles are turned off,” Dr. Shelby Harris, a sleep specialist at Montefiore Medical Center, told FoxNews.com. It occurs when you mentally awaken before the REM cycle is finished, but your muscles remain turned off.

According to Harris, as long as there is no known underlying cause for sleep paralysis, there is no need for concern. She recommends maintaining healthy sleep habits and managing stress to reduce the frequency of the condition. She adds that if you are still bothered by it, you can consult a sleep specialist who can prescribe certain medications and treatments.