Parasomni-Activity: The Real Story Behind Your Sleep Demon

Picture this: After a long and stressful day you finally climb into your cozy, safe bed for a goodnight’s sleep. You switch off the light, snuggle under your covers, and prepare for hours of peaceful rest. Except, they never come. Instead, you’re faced with something much, much scarier. An instinctive feeling comes over you as if something is very wrong. You try to move, but you can’t. You try to breathe, but it feels as if a boulder has been lowered onto your chest. Then you see it: A dark figure, standing in the corner of the room, staring at you through the darkness. You try to scream, but nothing comes out. You feel adrenaline and fear rushing through every part of your body as you lie there motionless, defenseless, exposed. 

Believe it or not, the scenario I’ve described is not uncommon for an individual undergoing a combination of sleep paralysis and hypnagogic hallucinations. Although I’ll define these terms later, you may better know this phenomenon as a ‘Sleep Demon.’ 

If you have browsed Instagram, Twitter, or TikTok in recent months, chances are that you’ve happened upon some variation of the “Sleep Paralysis Demon” meme. These memes feature a comical take on hallucinations that some individuals experience on the cusp of sleep. The ‘sleep paralysis demon’ trend spread across several content-sharing sites, seemingly enjoyed by a wide audience—and not just by those who have experienced the phenomenon firsthand. Of thousands of posts listed under this hashtag, the majority stick to a standard format: the main subject wakes up in bed (unable to move) and meets his or her very own ‘sleep demon.’ However, as content producers have recycled and augmented this meme, many of the resulting portrayals have become unrealistic, illustrating that some do not fully grasp the concept behind ‘sleep demons’ and the science that makes them possible. So, what causes these hellacious hallucinations? What is the science behind them, and how likely are you to come face-to-face with your own?

The Science of Sleep Demons

Sleep demons are not demonic intruders. Instead, they’re the result of an individual experiencing sleep disorders. There are actually six different categories of sleep disorders, but when analyzing the causes behind sleep demons, we need only look at Parasomnias: a group of sleep disorders that involve unwanted events or experiences that occur while you are falling asleep, sleeping or waking up (AASM). Common parasomnias include nightmares, sleep walking, sleep talking, and for our purposes: sleep paralysis and sleep hallucinations.

Before I discuss these two parasomnias, it is important to understand the circumstances in which they occur. Basically, there are three “main states of being: awake, REM (rapid eye movement) sleep, and non-REM sleep” (Cabotaje). Every night, we go through several sleep cycles lasting about 90-minutes. These cycles are mostly composed of non-REM sleep. In non-REM sleep, brain waves slow down and your muscles relax; this part of sleep handles healing and resting. The other 20% of your sleep cycle is REM sleep: the part of sleep where (most) of our dreams occur. REM sleep is a fascinating process where brain waves come alive while breathing, heart rate, and blood pressure increase. During this phase, your eyes move ‘rapidly’ as if they’re following the images in your dream. At the same time, your body becomes paralyzed; this prevents you from acting out your dreams and potentially hurting yourself. The two parasomnias required for sleep demons occur when your brain is in an ‘awake’ state, but your body is in a REM sleep state: you feel conscious, but you’re paralyzed. 

The Parasomnias that Make Them Possible

Now, an overview of these parasomnias. The first, sleep paralysis, is “the sensation of being awake, but unable to move your body” (Cabotaje). This parasomnia occurs during the transition from wakefulness to sleep (hypnagogic) or the transition from sleep to wakefulness (hypnopompic). In layman’s terms, when you are either falling asleep or waking up. Feelings of fear and anxiety often accompany sleep paralysis, due to the subject’s inability to control her own body. Many individuals also report feeling a force weighing on their chest, limiting their ability to breathe. Often while experiencing sleep paralysis, people will hear, see, or even feel things that aren’t really there. This leads to our second parasomnia: sleep hallucinations.

When one experiences a sleep hallucination, they may see, hear, feel, taste, or smell things and events that seem real but are, in fact, imagined. Due to their proximity to sleep, it can sometimes be hard to distinguish these hallucinations from dreams or, more commonly, nightmares. However, “when you wake up from a nightmare, you are aware that it occurred while you were asleep. It is clearly recognized as a dream. It is not thought to be real” (AASM). With sleep hallucinations, the individual often has trouble distinguishing the hallucination from reality. Sleep hallucinations alone sound terrifying. When combined with the immobility, confusion, and fear of sleep paralysis, it’s no wonder that some individuals suspect a demon of preying upon them in the night.

Sleep Demons and You

Despite how spooky sleep demons can be, they pose no threat and are actually pretty common. In fact, sleep demons have been a part of human history for centuries, often appearing in art or folklore (de Sá, Mota-Rolim). Many ancient cultures saw sleep demons as malevolent, supernatural beings who would sit upon your chest while you slept. Through medical advancements, we now know that they’re caused by stress, poor sleeping habits, and (sometimes) narcolepsy.

According to studies by University of Pennsylvania professors Brian A. Sharpless and Jacques P. Barber, as much as 7.6% of the general population experience at least one episode of sleep paralysis. While this rate is somewhat low, 28.3% (over one quarter!) of students reported at least one episode of sleep paralysis. But fear not: sleep demons seldom last longer than a couple minutes and can cause you no harm. Until we learn more about preventing the parasomnias that cause this phenomenon, the best approach may be to embrace your sleep demon with open arms and a comedic spin. 

Sources

AASM. “Sleep Hallucinations – Overview & Facts.” Sleep Education, sleepeducation.org/sleep-

disorders-by-category/parasomnias/sleep-hallucinations/overview-facts/.

AASM. “Sleep Paralysis – Overview & Facts.” Sleep Education, sleepeducation.org/sleep-disorders-by-category/parasomnias/sleep-paralysis/overview-facts.

“Brain Basics: Understanding Sleep.” National Institute of Neurological Disorders and Stroke, U.S. Department of Health and Human Services, www.ninds.nih.gov/Disorders/patient-caregiver-education/understanding-sleep.

Cabotaje, Angela. “Why Those Late Nights Are Causing Your Sleep Paralysis.” Right as Rain by UW Medicine, 19 Oct. 2018, rightasrain.uwmedicine.org/body/sleep-paralysis.

Davis, Kathleen FNP. “Sleep Paralysis: Causes, Symptoms, and Tips.” Medical News Today, MediLexicon International, 12 June 2015, www.medicalnewstoday.com/articles/295039.

de Sá, José F R, and Sérgio A Mota-Rolim. “Sleep Paralysis in Brazilian Folklore and Other Cultures: A Brief Review.” National Center for Biotechnology Information, U.S. National Library of Medicine, Frontiers Media S.A., 7 Sept. 2016, www.ncbi.nlm.nih.gov/pmc/articles/PMC5013036/.

Elliott, Josh K. “Why the Paralyzing 'Sleep Demon' Still Haunts Humans in the Age of Science.” Global News, Global News, 20 Apr. 2019, globalnews.ca/news/5177498/sleep-paralysis-demon-science/.

Sharpless, Brian A, and Jacques P Barber. “Lifetime Prevalence Rates of Sleep Paralysis: a Systematic Review.” Sleep Medicine Reviews, U.S. National Library of Medicine, Oct. 2011, www.ncbi.nlm.nih.gov/pmc/articles/PMC3156892/.