You’re drifting lazily through hazy dreams when you abruptly become aware of your surroundings. Annoyed that your nocturnal sojourns are coming to an end, you roll onto your side – only it doesn’t happen because you are suddenly, inexplicably, unable to move. You may sense an evil presence in the room, perhaps something heavy upon your chest or hands around your neck. As panic mounts you attempt to cry out for help, only that doesn’t work either because you are also unable to speak.
Ever experienced this? It’s called sleep paralysis, and it’s perfectly natural.
What is Sleep Paralysis?
Sleep paralysis (SP) refers to the condition in which a person, usually lying on his back (in a supine position), is about to fall asleep or has just awoken to find himself incapable of movement or speech. It may last anywhere between several seconds to several minutes, during which time the individual may experience mounting fear and panic as well as various forms of sensory hallucination that may be either fantastical or horrific.
The Symptoms of Sleep Paralysis
Sleep paralysis is characterised by inability to the body or limbs at the onset of sleep or upon awakening, brief episodes of partial or complete skeletal paralysis, and very often episodes of hallucinations, known as hypnagogic and hypnopompic experiences (HHE). It is frequently accompanied by panic, heightened by the inability to speak or cry out. A polysomnograph (sleep recording) will also demonstrate the suppression of skeletal muscle tone, a sleep onset Rapid Eye Movement or ‘REM’ period and dissociated REM sleep.
All too often the hallucinations manifest in the form of an evil presence nearby, which may be engaged in the relatively benign activity of keenly observing the sleeper – or they may become malevolent and attack the individual. Various other forms of hallucinations may also be encountered, including exosomatic (waves, vibrations and tremors), acoustic (high-pitched ringing, loud or irritating noises), visual (blobs of light, perception of extreme detail in objects), somatosensory (the feeling of one’s body being twisted, rotated or compressed, or the sensation of flying or floating), dissociative (out-of-body experiences) and physical (sudden pain in parts of the body) hallucinations1. In some cases, extreme effort to move parts of the body may result in phantom movement whereby the individual feels as though the body part involved were indeed moving even though visual confirmation reveals the contrary. These hallucinations range in intensity from fleeting illusion to full-blown, true hallucination (prior knowledge of this condition tends to soften the blow). However, so vivid are some of these barrages of sensory hallucination that even after the paralysis wears off, the individual is left with a lingering anxiety or dread – especially if that person has never before heard of sleep paralysis – an individual may feel that their sanity is hanging by a thread.
A Short History
‘[Those] taken with this disease, imagine that a man of monstrous stature sitteth on them, which with his hands violently stoppeth their mouth, that they can by no meanes cry out, and they strive with their armes and hands to drive him away, but all in vain.’
– Ludwig Lavater, 16th-Century Swiss minister.
There are numerous documentations of sleep paralysis and associated hallucinations throughout history. In the East, descriptions of these conditions date as far back as 400BC, accounted in a Chinese book of dreams. The famous Greek physician Galen attempted to study the cause of nightmares; both the Greek historian Herodotus and the Roman poet Horace chronicled appearances of the evil entities associated with this condition. Similarly, the word ‘nightmare’ was originally conceived in the West to describe sleep paralysis. The word ‘mare’ from the Anglo-Saxon word ‘merran’, meaning ‘to crush’, dates back to old English belief that witches or other supernatural beings were responsible for the chest-crushing sensations experienced in sleep paralysis. The term has since transformed into ‘nightmare’ (the crusher in the night), which we have now come to associate with horrific dreams of monsters and mishap.
Although most of these documentations attribute sleep paralysis to supernatural phenomena, several key figures have attempted to explain it logically. Galen thought the condition was caused by gastric disturbances. Even in the age of religious superstition, 16th Century Swiss minister Ludwig Lavater asserted that, ‘physicians do affirme, that these are nothing else but a disease’, an opinion that (strangely enough) both the enthusiastic witch-hunterJames I and the Elizabethan sceptic Reginald Scot agreed upon. Samuel Wesley chose to remain neutral on the subject, claiming that the experiences could have a natural or supernatural cause depending on particular personal circumstances. Ernest Jones, a Freud pupil, was convinced repressed sexuality was to blame.
And then came the invention and development of electroencephalography the 1950s, which paved the way for research on sleep patterns and, coupled with the anthropological work of researchers such as Robert Ness and David J Hufford, opened up a new understanding of what we now know to be a neurological glitch.’