We’re afraid of the unknown; what lies beneath our beds, and inside our closets. We fear tomorrow, change, reality, death, and what lies beyond. It’s difficult to understand, and easier to create, and confide in myth, legend, and folklore.

Like many odd scientific phenomena, sleep paralysis has been misinterpreted throughout the centuries and among varying cultures.

The experience has been the “paranormal-magnet” since ancient times; yes, sleep paralysis has been recognized for centuries, noted down, and observed in great depth by scientists throughout the ages. In fact it was the dawn of the nineteenth century, when psychology and the inner workings of the human mind had begun to be analyzed in greater depth, that the experience was considered sleep palsy for the first time.

Sleep paralysis can be a difficult condition to analyze under solely scientific terms. After all, it’s spooky as hell!

Imagine awakening in the middle of the night, unable to move, a boulder on your chest, accompanied by a supposed negative presence, swishing about the bedroom like a dark shadow; pretty damn freaky. Under such circumstances it’s unlikely that a victim won’t succumb to such compelling “external” stimuli.

However, people often attach bogus solutions to forces in nature we don’t quite understand. The result? An answer that makes sense to us, and an opportunity to justify our beliefs by analyzing the process through our own perceptual set, and thereby turning an independent system into something that coincides with our prior “truths.” Kind of like how we’ve turned something clearly neurologically linked, into something religious, spiritual, and paranormal.

Accounts of sleep paralysis can be traced as far back as to Persian medical texts dating back to the tenth century. The first clinical observation was made by a Dutch physician in 1664 who diagnosed a fifty year old woman with “Night-Mare.” It was believed to be caused by demons or spiritual possession, just like the many other cases observed around the world at the time.

It’s almost funny how blind humans can be; something can occur throughout the world regardless of one’s beliefs, faiths, and values, yet we continue to justify the false likelihood of the incident correlating to something like religion.

Fluctuating factors cannot influence consistent symptoms.

Whoever the victim, whatever their beliefs, wherever they reside, the basic symptoms of sleep paralysis, are the basic symptoms of sleep paralysis, everywhere.

Sleep paralysis is also surprisingly common. A friend of mine, Glen Harthorne, now a senior at Doherty Memorial High School in Worcester, Massachusetts, volunteered to share his own struggle with the condition.

“I usually have a dream of either something creepy, odd, (demonic maybe?), and I can feel myself snap awake. But I can't move. I try to remain calm but I can only move my eyes or sometimes can't even open my eyes and it's terrifying. I know I'm awake but I feel like I'm suffocating from panic. I've seen shadows move where they shouldn't move if that counts as hallucinations. I just feel so helpless and I can't control it. I just lay there, hoping for it to be over as fast as possible.”

Unlike many other sufferers, Glen understands that though terrifying, his condition, despite how extremely compelling and tempting it may be to label a spiritually, or religiously linked experience, it most likely is not.

So how does it really happen?

When victims of sleep paralysis enter deep REM sleep, their brain tells the body’s voluntary muscles to relax and go into a state of paralysis, which is called atonia.

Atonia actually protects the body from injury by preventing one from acting out the physical movements in their dreams. In other parasomnias, such as sleepwalking or REM sleep behavior disorder, atonia doesn’t occur properly and the voluntary muscles move while the mind remains asleep, which is why people may be prone to acting out insane actions in their sleep while remaining completely unaware.

In sleep paralysis, the body remains paralyzed in REM atonia while the brain awakens and the eyes start to open. Sufferers become alert in a transient conscious state, but they are unable to move voluntary muscles or speak. Although involuntary muscle movement, like breathing, is not affected, there is often a sensation of chest pressure, which is why many people wake up from sleep paralysis gasping to take a deep breath. Episodes can last anywhere from 20 seconds to a few minutes.

The mental shock sufferers undergo once they're aware of their paralyzed state, triggers fight or flight, and contributes to frightening hallucinations and increased heart rate. The victim's personal beliefs may definitely influence the hallucinations they see. For example, would a Buddhist monk see an image a Christian may label demonic? Would a skeptic see anything paranormal at all? These are valid questions that are yet to be researched in depth.

Though science has advanced to explain how sleep paralysis occurs, it is yet to uncover the why factor.

While some scientists believe sleep paralysis can be linked to prominent mental illnesses sprinkled throughout family history, others believe the cause may be linked to sleep deprivation.

Sleep deprivation correlates to the degradation of mood, and the two factors feed off one another to create a vicious cycle that can really take a toll on healthy neural function.

In fact when asked if he were more likely to undergo sleep paralysis under any specific circumstances, Glen interestingly noted, “It usually happens when I go to sleep upset over something. Angry or depressed is when it happens. I can't recall a time when I've gone to bed content and had it happen.” Those familiar with my former article, “Feeling Depressed,” may remember that negative moods are primary factors in many mood and anxiety disorders.

So if sleep paralysis is something you struggle with, make sure you’re getting enough sleep and you’re not doing things that compromise the quality of your sleep, like drinking a lot or eating right before bed.