Have you ever wondered how or why sleep paralysis occurs? I have always been curious about the idea of it and how it is possible. Different psychological theories are behind the cause of visioning “spooky sensations” floating outside your body or gazing down at you. Sleep paralysis is more than just a nightmare. Instead, it is “…a nightmare coming alive before your eyes” (“Why Sleep Paralysis…”). When you experience sleep paralysis, your brain temporarily paralyzes your body. So, when you see a surreal sight, you physically cannot move to try to “fight” it because your brain is stopping your body from hurting yourself. The motor cortex in your brain sends signals to the body to escape the paralysis when you realize you’re paralyzed. This brain area isn’t detecting any movement in your limbs, where temporary paralysis comes in. Sleep paralysis is an out-of-body experience where the “self” leaves the physical body. The temporoparietal junction is a brain region in the parietal lobes, the top middle part of our brain, that helps us build our “body image” or sense of self. Generally, this region in your brain is turned off during REM sleep, so we lose our “body image.” During sleep paralysis, disturbances to your sense of self can occur, causing those surreal visions. The brain can be compared to a prediction machine in which it is “…always in the business of generating internal models of the world and what your body might be up to next and will try to live up to those expectations” (“Why Sleep Paralysis…”). Moreover, your brain will construct your body image for you, causing eerie hallucinations.

Baland Jalal, the author of “Why Sleep Paralysis Makes You See Ghosts,” has three possible theories regarding how you can see ghosts. The first is the idea that circuits in your brain that are critical for understanding the intentions of others are involved. Jalal emphasizes, “Ordinarily, when you “see” the world from another person’s perspective, you don’t feel like you’re leaving your body-you don’t have an out-of-body experience. This is because the activity of these circuits is kept in check by sensory feedback from your body and front brain areas” (“Why Sleep Paralysis…”). During the stage of REM sleep, there’s no feedback from your body and front brain regions, causing the barrier between your sense of self and others to dissolve. Moreover, imagining “…a ‘virtual body’ (a bedroom intruder) may manifest as a literal (hallucinated) body with agency and intentions” (“Why Sleep Paralysis…”).

The second theory is that our brains are a “…statistical machine and master storyteller” (“Why Sleep Paralysis…”). Remnants of REM sleep can be twisted into a coherent story your brain wants to believe. Your brain can spin a story by pulling from memory regions and completing the narrative. The things your vision does not come from only the outside world but also from the inside out. Essentially, it is “…your brain’s best guess of what is out there” (“Why Sleep Paralysis…”).

The third and final theory is about neurochemical fluctuations in our brain, which create the right environment for surreal visions. The brain uses serotonin to wake someone up, and during sleep paralysis, invasion of wakefulness while in REM sleep can flood the brain with too much serotonin. This can stimulate serotonin “talking” with the brain, the so-called “serotonin 2a receptor.” Jalal asserts that “Intensely tickling this receptor is known to make you prone to ascribe meaning to otherwise ‘meaningless’ things and triggers irresistible fear” (“Why Sleep Paralysis…”). This serotonin receptor is also linked to psychedelic drugs such as LSD and psilocybin, causing mystical experiences. The receptor can turn a physiological experience into a supernatural encounter.

Overall, the psychology behind sleep paralysis is sometimes challenging and unbelievable. Baland Jalal expresses his final opinion and emphasizes that the theory fits previous observations. He claims, “When the temporoparietal junction is disrupted using an electrical current, instead of having an out-of-body experience, you sense a shadowy figure. This ‘ghost-like double’ is perceived to stand behind you, mimicking your postures. Similarly, there is a striking resemblance between sleep paralysis hallucinations and those triggered by hallucinogenic drugs, suggesting shared neurobiology.