They Only Come Out at Night
Cambridge University Press eBooks March 1, 2026 DOI: 10.1017/9781009322348.005 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Theoretical or philosophical paper Peer reviewed |
|---|---|
| Keywords | Liminality Sleep paralysis Perception Sensation Narrative Sleep system call Perspective graphical Aesthetics Cognitive science Distressing |
| Key points | Argues that sleep paralysis experiences arise from the collision of REM-sleep paralysis persisting into wakefulness and perceptual ambiguity, with the temporoparietal junction involved in out-of-body experiences and sensed presence. |
Abstract
Sleep paralysis is one of the most terrifying experiences a person can have—and it’s surprisingly common. Cultures around the world describe eerily similar episodes: waking up unable to move, a crushing pressure on the chest, and the overwhelming sense that someone—or something—is in the room. This chapter explores how those experiences may arise from the collision of sleep architecture and perceptual ambiguity. It covers the basic neurobiology of REM sleep, explains what happens when paralysis persists into wakefulness, and investigates how hallucinations can emerge in these liminal states. The chapter also examines the role of the temporoparietal junction in out-of-body experiences and the sensation of a nearby presence. Rooted in both science and cultural context, this chapter offers a grounded explanation for a deeply human phenomenon—one that’s haunted people for centuries and continues to blur the line between brain and belief.