J. A. Cheyne

2 papers in the library · publishing 2002-2005

Papers

Sleep paralysis episode frequency and number, types, and structure of associated hallucinations

Journal of Sleep Research September 1, 2005 J. A. Cheyne

Sleep paralysis hallucinations fall into three categories thought to stem from REM sleep processes, but prior studies mixed people with different levels of experience. This survey of 5,799 current sleep paralysis experiencers compared novice and frequent experients. Hallucination types and variety differed with episode frequency, yet the three-factor structure remained consistent across groups. Novices showed clearer separation between hallucination types, while frequent experients tended to blend experiences across episodes. Earlier onset of sleep paralysis was linked to more frequent episodes. The findings support the idea that the basic organization of sleep paralysis hallucinations arises from intrinsic REM-related processes, independent of prior experience.

DOI: 10.1111/j.1365-2869.2005.00477.x

Situational factors affecting sleep paralysis and associated hallucinations: position and timing effects

Journal of Sleep Research June 1, 2002 J. A. Cheyne

Sleep paralysis (SP) is a temporary inability to move or speak when waking up or falling asleep, often accompanied by frightening hallucinations. Two studies involving 6730 subjects, including 4699 who had experienced SP, examined how body position and timing affect SP. More individuals reported SP while lying on their back (supine) than in all other positions combined. The supine position was three to four times more common during SP than during normal sleep. SP episodes occurring in the middle or at the end of sleep were more likely to involve the supine position than those at the beginning, suggesting later episodes may arise from brief awakenings during REM sleep possibly triggered by apnea.

DOI: 10.1046/j.1365-2869.2002.00297.x