Have you ever woken up only to find yourself unable to move a muscle? This is not a case of having difficulty getting up in the morning. Sleep paralysis can happen when entering sleep (hypnagogic paralysis), or when waking (hypnopompic paralysis).
For the sake of clarity it is necessary to distinguish between two kinds of sleep paralysis. The one is normal and absolutely necessary and occurs during REM sleep in order to essentially disconnect the body from the dreaming mind so that it wont thrash about attempting to enact the rigors of dream-life and hurt itself doing so.
Dysfunctional sleep paralysis, sometimes known as "awareness during sleep paralysis", occurs when the mechanism that disconnects the brain from the body fails to reconnect upon awakening. The brain has left the REM state behind but the body paralysis persists.
Though this 'out of synch' stage may only last a very short time - normally no more than two minutes - it can seem much longer to the consciousness having the experience. Sleep paralysis, the inappropriate kind, is often associated with perceptual inaccuracies that can range from fleeting illusions to full blown hallucinations.
Studies show that hallucinations may range from the "full-blown", where the hallucinatory believes that the experience is 100% real and objective, to the pseudo which is still vivid but lacking the substantial quality of regular perceptual experience.
Most experiences of sleep paralysis fall into the pseudo-hallucinatory category where there is an almost ethereal quality that does little to detract from the powerful level of fear that typically accompanies the experience.
Statistics report that 20% to 40% of people report having had some or other version of sleep paralysis. For a third of them the experience is nothing more than a momentary fear of the possibility of paralysis followed by a swift return to normal. Because the experience may be barely noticeable, or simply ignored, it is considered entirely possible that everyone has experienced sleep paralysis in one form or another.
A substantial two thirds of those who report having experienced sleep paralysis describe episodes of hypnagogic and hypnopompic hallucinations of varying degrees. In simple language the hallucinations are similar in nature, distinguished only by their association with those experienced at sleep onset and those upon waking.
Features of the hallucinations have often been postulated as an explanation for the proliferation of reports of alien abduction and demon visitation. The reason for this is the characteristic nature of the hallucination. There tends to be certain uniformly experienced features that include the "sense of a presence" that is felt to be malevolent in nature.
People who suffer from sleep paralysis often report the sense of there being someone in the room with them. They speak of a pressure or weight felt on the body, often in the vicinity of the chest area.
Hearing and seeing things will often accompany these hallucinations. Less common is the sense of floating out of the body and the tactile experience of being touched or grabbed.
A rare number of sufferers speak of a falling sensation or vibrations. Whatever the particular configuration of symptoms all report a vivid level of fear. This is shared by all, even those who, on some level, recognize that the experience is not altogether real.
This vivid and horrific experience of sleep paralysis is not culture specific. It affects people across the world and literature and mythology are full of references to it. In Canada it is called "a visit from the old hag", in Japan it is being "bound and fastened in metal". The Mexicans use a phrase that means " the dead getting on top" and in the southern United States it is known as "the witch riding your back".
Often associated with the serious disorder, narcolepsy, the occurrence of sleep paralysis is thought to be associated and exacerbated by sleeping in a supine position coupled with increased stress levels, disturbed sleep schedules and/or sudden changes in environment or lifestyle.
Studies show that sleep paralysis tends to be reported from an early age, around ten years old, peaking at 17 and then reducing markedly thereafter. Although the experience is a disturbing one and may even trigger a search for meaning that may include suppositions of alien abductions or demon possession the actual disorder is considered to be terrifying but benign.
People who suffer the condition on a regular basis sometimes form support groups where ways of coping are discussed and exchanged. The basis of this informal treatment is principally centered on ways of coping with the high levels of fear. Learning to relax, breathe and let the situation resolve itself are suggested along with a step by step physical exercise beginning with the extremities and working towards the core.