For a few years now I have experienced sleep paralysis. Every time it happens it is usually the same thing: I feel like I am awake but I am unable to breathe, move, or speak, and I struggle to kick my leg to snap myself out of it. Once, along with this feeling of paralysis, I couldn’t tell if I felt the presence of something demonic in the room with me or if I fell back to sleep and simply dreamed about it – but it is an occurrence I am not alone in experiencing based on stories I’ve read. I have met people who have never endured sleep paralysis, even though it is something I seem to undergo very often. It makes me wonder many things, but one of the more prevalent questions I have is, is sleep paralysis associated with hallucinations?

By research from the Periodic Paralysis Association, who conducted studies to observe patients with sleep paralysis, they were able to define, find symptoms, prevention, why and when sleep paralysis occurs. For those who do not know, sleep paralysis is a moment of time when you are in between sleeping and waking, unable to move or talk. The Association supports my inquiry that the phenomenon causes hallucinations for some people. There are even three different types of these illusions, including the incubus, the intruder, and unusual bodily experiences. These findings first influenced me to find how many people suffer from hallucinations during paralysis.

According to a study by Ethan Green, he surveyed people who faced sleep paralysis and asked several questions, including what they experienced during their episodes. Almost 30% of the thirty thousand voters answered that they believed there was a demonic presence or entity – the same thing I encountered. This is due to the brain activating its flight-or-fight response when REM sleep is interrupted, increasing the body’s adrenaline and creating a hallucination that poses as a threat when you are falling asleep. This further creates the feeling that whatever you think is in the room with you is evil because while you are scared about being unable to move or breath, it is overdramatizing your perception of what is going on.

Image source from World of Lucid Dreaming

Now that I’ve discovered evidence that people have hallucinations during sleep paralysis, I’m going to discuss the three types. Another survey presented by Cheyne, Rueffer, and Newby-Clark in 1999, summarized by Mental Health Daily, questioned people who had gone through sleep paralysis, creating categories under which their hallucinations fell. The first is intruder, where subjects believe they have company in the room with them, aka the demon sensation that’s been explained. While you are stuck in the in-between state, one can also hallucinate by hearing talking or strange noises. For the incubus group, it entails feeling such intense pressure upon one’s body that he or she cannot breathe and may even experience pain. A surprising characteristic, which connects to the intruder group, is that sufferers sometimes think something is trying and about to succeed in killing them. Lastly, the category found more positive than the others, is that of unusual bodily experiences. People report feeling dissociated from their bodies, as if they are flying around their rooms, for example, or feel completely peaceful during their paralysis.

Image source from Thought of Interest

First and foremost, polls and surveys are observational, so the data is reliant on the samples questioned. If there is anything I learned about surveys in my past psych and stat classes, it’s that response bias is a huge confounding variable. Research is skewed based upon how many people who experienced sleep paralysis actually responded, and also whether their answers were truthful or not. So looking at my sources, surveys are not always reliable and some of the research comes from around 1999, which isn’t terribly old but also is not the most recent information. The evidence is in favor of my question; sleep paralysis seems to correlate with hallucinations, but nothing is ever “proven” by researchers. Also, from what we’ve learned in class, there are easily other confounding variables here, and I wonder if reverse causation is possible, in that hallucinations are actually making people experience sleep paranoia. That doesn’t seem plausible, though, for the hallucinations occur once a person is already falling into or waking up from REM sleep.

From what I learned, it seems like I may go through sleep paralysis again in my lifetime, with hallucinations as a symptom from it. If you read this and you suffer from sleep paralysis occasionally like me or are experiencing extreme fear from it, I would recommend going back to the Period Paralysis Association page and reading their section on prevention. Especially as a college student, make sure you follow some of their advice – your homework probably already has you on edge, and I’m sure you don’t want to add hallucinating about demons to it.