Sleep Paralysis and  Associated Hypnagogic and Hypnopompic Experiences 

(Revised August 20, 1998)

In this site we describe many of the features of sleep paralysis and associated experiences. The material below has been gathered from many sources, but much of it from our own research into the sleep paralysis experience. As data is collected we update the information provided at this site. Thanks to the many people who have shared their experiences with us we have recently been able to provide a very much expanded account of our understanding of sleep paralysis. 
It will be very much appreciated if you will take some time to fill out the Waterloo Unusual Sleep Experiences Scale before reading on. You might actually find the information more relevant if you take a few minutes to fill out the questionnaire now.

To your protection I commend me, gods. 

From fairies and the tempters of the night Guard me, beseech ye!

Imogens's prayer, Cymbeline, Act II, Scene 2

The Bewitched Groom 

The True Night-mare: Sleep Paralysis with Hypnagogic and Hypnopompic Hallucinations

J. A. Cheyne
Department of Psychology
University of Waterloo

    Sleep Paralysis

      Hallucinations (HHEs) during Sleep Paralysis 
      Frequency of HHEs

    SP and REM

    The True Night-Mare: SP in Myth and Legend

    The Intruder

      "Mere" Presence 
      A Monitoring Presence 
      Realistic Interpretations 
      An Evil Presence 
      The Presence and the Terror 
      Auditory Hallucinations 
      Visual Hallucinations 
      The Intruder and REM

    The Incubus

      Chest Pressure and Breathing Difficulty 
      Incubus and REM 
      SP and Tonic Immobility 

    Unusual Bodily Experiences

      Out-of-Body Experiences 
      Unusual Bodily Experiences and REM

    Preventing Sleep Paralysis

Other Articles about and Resources for Sleep Paralysis
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