Imagine waking up at 3 a.m. to find a shadowy figure standing in the corner of your bedroom. You try to scream, but nothing comes out. You try to move, but your body refuses to cooperate. At this moment, you might be thinking that you need an exorcist. However, before jumping to conclusions, you might want to see a neurologist instead, what just happened was likely sleep paralysis.
This eerie experience, known as sleep paralysis, is something most children fear. However, that daunting figure may be more of a neurological phenomenon than a supernatural one.
To understand why our brains turn bedtime into a horror movie, we first need to look at what happens while we sleep.
Every night, your body cycles through three stages of non-REM (rapid eye movement) sleep as shown in Figure 1. After returning to stage one, your body enters a period of REM sleep (Denis 2015). During this stage, brain activity increases and you begin to experience your most vivid dreams. While the brain generates these dreams, the body enters a state of REM atonia, a temporary paralysis affecting most voluntary skeletal muscles. This process is regulated by two inhibitory neurotransmitters in the central nervous system: gamma-aminobutyric acid (GABA) and glycine, which reduce the activity of motor neurons. This prevents you from physically acting out most of your dreams (Jalal 2018). When you begin to wake up, the body gradually regains awareness and movement. Sleep paralysis occurs when awareness is gained before voluntarily movement.
So where might this mysterious presence come from? One possible explanation involves the body schema, an internal representation of your body’s position and movement. This system relies on brain regions such as the superior parietal lobule and the temporoparietal junction. These regions help integrate sensory information to construct the brain’s representation of your body (Taylor 2026).
However, during sleep paralysis, the usual relationship between movement and sensory feedback may be disrupted. Your central nervous system sends efferent signals to your limbs, but due to the temporary paralysis, your brain does not receive the expected afferent signals back. According to one hypothesis proposed by Jalal and Ramachandran(2017), this mismatch may distort the brain’s representation of the body. This causes it to project its internal body map, known as the homunculus (see Figure 2), into the surrounding environment.
The amygdala, a brain region involved in processing fear, may then amplify the threat created by this mysterious presence. The fear of being unable to move, combined with your cultural beliefs and expectations may shape this presence into something frightening, such as a demon or shadowy figure (John Fakoya et al. 2018).
This is one of many proposed explanations for these hallucinations, and the exact mechanisms remain a mystery. So, the next time you spot a shadowy figure in your room, it may just be your brain. But then again, I don’t recommend tossing that exorcist’s number just yet.
References
Baugh, Sue. 2023. “Homunculus | Description, History, Models, & Importance | Britannica.” Www.Britannica.Com. Accessed October 18, 2026. https://www.britannica.com/science/homunculus-biology.
Denis, Dan. 2015. “Understanding Sleep Paralysis: A Terrifying but Unique State of Consciousness.” The Conversation, October 5. https://theconversation.com/understanding-sleep-paralysis-a-terrifying-but-unique-state-of-consciousness-48509.
Jalal, Baland. 2018. “The Neuropharmacology of Sleep Paralysis Hallucinations: Serotonin 2A Activation and a Novel Therapeutic Drug.” Psychopharmacology 235 (11): 3083–91. https://doi.org/10.1007/s00213-018-5042-1.
Jalal, Baland, and Vilayanur S. Ramachandran. 2017. “Sleep Paralysis, ‘The Ghostly Bedroom Intruder’ and Out-of-Body Experiences: The Role of Mirror Neurons.” Frontiers in Human Neuroscience 11 (February). https://doi.org/10.3389/fnhum.2017.00092.
Olunu Esther, Ruth Kimo, Olufunmbi Onigbinde, et al. 2018. “Sleep Paralysis, a Medical Condition With a Diverse Cultural Interpretation.” International Journal of Applied and Basic Medical Research 8 (3): 137. https://doi.org/10.4103/ijabmr.ijabmr_19_18.
Taylor, Kenji. 2026. “Sleep Paralysis Hallucinations Aren’t Random—Here’s What Triggers Them. | Ubie Doctor’s Note.” Ubiehealth.Com, Ubie, Inc., January 16. https://ubiehealth.com/doctors-note/sleep-paralysis-hallucination-trigger-cause-37-why122e3.
Comments
17 Responses to “The Haunting on REM Street”
Hi Isci!
I chose this topic because I thought it would be nice to embrace the scary halloween and exam season through a spooky read. This topic is also one I can relate to, as I’ve experienced sleep paralysis frequently for almost two years now, and yes, I have seen the shadow figure hallucinations. Despite experiencing this myself, I never really looked into the hows or the why behind it and thought this would be the perfect chance to explore its science.
This topic connects to isci through its psychological concepts and our lesson on the nervous system. Specifically, in our psychology lesson we learned about the inhibitory neurotransmitter GABA. This topic allows me to bring together different areas of science to understand a common personal experience. Feel free to leave me any suggestions, I hope you enjoy reading!
Zahra Imthiyas
Hi Zahra,
This is a very well written post. I especially loved your hook! It was really intriguing. My only suggestion to further polish your blog would be to add a little more detail to your figure captions! They are not a part of the word count and are really useful to add more context to your post. Excited to read the final draft!
Joycee
Hey Joycee, I appreciate you telling me figure captions are not a part of the word count because I was unaware of that fact. I have added a lot more detail to both my figure captions. Thank you so much for the helpful feedback, I am glad you enjoyed the read.
Thank you,
Zahra
Hi Zahra,
Great work. This is a well-written draft. Here is some feedback:
– Make sure to define any acronyms you use. GABA in paragraph 3 is not defined, and most likely not common knowledge.
– I recommend splitting the last sentence into 2 by removing the “however”, for better flow. Consider rewording the last portion to: “Sleep paralysis occurs when awareness is gained before voluntary movement.”
– Make sure to hyperlink your citations. I should be able to click them and visit the page you sourced.
I am excited to read the final draft! Happy editing!
Angie
Hey Angie, thank you for your helpful suggestions, especially telling me to hyperlink my citations. I have made the following improvements and really appreciate the help.
Thank you!
Zahra Imthiyas
Hey Zahra,
This is a super interesting topic! Some suggestions I have:
– Ensure to define your acronyms before the first time you mention it (e.g ” rapid eye movement (REM)”)
– In your citation “John Fakoya..” I believe that John Fakoya Adegbenro Omotuyi is one person, and Esther Olunu is the primary author of the paper you cited, so they should be listed first.
Have a good time editing!
Hanna
Hi Hanna, I have fixed the author list on my citation as well as defining the term GABA. Thank you for the helpful feedback!
Zahra
Hi Zahra,
Great job on your blog post – you chose a fascinating topic and did a great job captivating the reader from the start! Here are just a few small suggestions I had for your edits:
– Make sure to reference both figures somewhere in your text.
– Consider expanding on your figure caption for Figure 1 to explain the different stages of sleep so the reader can better understand the chart.
– In the last sentence of paragraph 4, I would suggest adding a comma between the words “movement” and “that”.
Overall, great job and good luck with your edits!
– Kristen
Hey Kristen, I have created a more detailed figure caption for both Figure 1 and Figure 2, and reference them in my text. However, I am not able to do the last suggestion because I reworded it as recommended previously. Thank you for your helpful suggestions.
Zahra Imthiyas
Hi Zahra!
This was a great blog post on an interesting topic! A few small things:
– In the paragraph directly below figure. 1 there is some awkward wording in “before voluntary movement that is when sleep paralysis occurs.” at the end. I think removing the that in the section or rewording it will be more correct and make your paragraph more clear.
– In psychology during one of the lectures we went over inhibitory neurotransmitters such as GABA! Not feedback, just something interesting to add that further connects to lecture.
– The Baugh Britannica page you cited actually does have a date that you can add, as you can check the history of the article, which was last updated in 2026 and added in 2023.
– In your second to last citation, you forgot to put a space in the name AdegbenroOmotuyi. You may also want to recheck the rules looking at listing multiple authors of an article in a citation.
– I think you struck a really good balance between engaging the audience and being scientifically accurate!
Overall I’m excited to see where this goes!
Nima
Hey Nima, Thank you for all your helpful feedback! I have made the following corrections, and added a comment relating GABA to our psychology lesson to my comment. For my second last citation I corrected the order of authors so it reflects the rules of citation better.
Thank you
Zahra
Hi Nima,
What a fun read! You did an amazing job making your writing super engaging and clearly articulating your ideas! Here are a few suggestions:
-P1: For better flow, I would suggest combining your last two sentences!
-I think P1 and P2 could also be combined together!
-Make sure that you are introducing figures in the text before showing the figure! This might mean moving your body paragraphs so they come before your figure. Ex. P4
Overall, you did a fantastic job and I cannot wait to read your final copy.
Happy editing,
Via
Hi Via, thank you for your helpful feedback! I combined the last two sentances of my first paragraph and switched the order of my paragraphs so the figure is introduced first. However, I think keeping paragraph 1 and 2 separate keeps a strong voice when introducing my topic. I really appreciate you taking time to give me suggestions!
Zahra
Hi Zahra,
This was a great read, always wondered what exactly caused sleep paralysis and enjoyed reading about some of they hypotheses you researched! I did notice some things that you could correct though:
– In the first sentence of P1 – “Imagine waking up at 3 a.m” there is a missing period after the m (should be 3 a.m.)
– There is a missing comma on the first sentence of P2 – “This eerie experience known as sleep paralysis, is something…” should be “This eerie experience, known as sleep paralysis, is something”
– “Hypnongram” is misspelled in Figure 1. It should be corrected to “Hypnogram”
Overall great blog post!
Daniel
Hi Daniel, thank you for your feedback, I have made the following adjustments to my draft. I hope my read helped explain sleep paralysis a little more.
Thank you,
Zahra
Hi Zahra,
I love the title, it’s a great hook! Especially for the Halloween season!
I just have a couple of suggestions for you:
I would explain your figure a bit better by defining the three different sleep stages and what they mean, as well as clarifying what a SOREM period is in sleep.
After the sentence, “This process is regulated by two inhibitory neurotransmitters in the central nervous system: GABA and glycine, which reduce the activity of motor neurons,” I would briefly explain what these inhibitory neurotransmitters are.
For the sentence, “According to one hypothesis proposed by Jalal and Ramachandran, this mismatch may distort the brain’s representation of the body,” I would consider adding a citation.
Lastly, if the word count permits, I would explain how we experience more REM sleep in the morning hours, which is why sleep paralysis often happens around 3 AM.
Overall, great job and happy editing!
Hey Abbie! Thank you for your helpful comments, I have made some changes based on your suggestions. I explained what SOREM is in my figure caption and added a citation after introducing the hypothesis. However, unfortunately I do not have the word count to further explain sleep paralysis, and GABA and glycine.
I appreciate your help!
Zahra