Sleep paralysis (Article from the trustable "Guardian")

Definition of Sleep Paralysis:
Sleep paralysis: A frightening form of paralysis that occurs when a person suddenly finds himself or herself unable to move for a few minutes, most often upon falling asleep or waking up. Sleep paralysis is due to an irregularity in passing between the stages of sleep and wakefulness.

The symptoms of sleep paralysis include sensations of noises, smells, levitation, paralysis, terror, and images of frightening intruders. Once considered very rare, up to half of all people are now believed to experience sleep paralysis sometime during their life. Sleep paralysis is not considered to be a sign of a serious condition, although it can be frightening.

Yesterday night I was so shaken I wanted to look for the medical reason for it. This is a brilliant article I found on the Guardian.
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By the time Matthew Jones-Chesters switches off the light, it's late. He's overtired and tense, anxious about the day ahead. Slowly he slips off, but then suddenly he's awake - and he's not alone.
Rooted in bed, he watches as, yet again, the horror unfolds. 'A black shape gathers in the corner of the room, as if from nothing. I can see it, like a huge bat, massive and caped. It fills the room and comes closer and eventually it's around me, cloudy and dark. I feel its pressure and it's holding me and then, under its weight and power, I feel I'm sinking and being dragged down.


'I fight to bring myself back round, but I can't - and this is the awful part - I can't because I'm totally paralysed. The best I can do is make a noise in my throat in the hope I'll bring myself round. It's horrible.


'Every few months, Dr Jones-Chesters, 30, endures this nocturnal torture. A neuropsychologist who works for North Essex Mental Health, he knows perfectly well he isn't being visited by devils, ghosts or anything from the realms of the X Files. But that doesn't make the experience any less spine chilling, and it's only mildly comforting to know that it has a name.Sleep paralysis is perhaps one of the last closet conditions. Few admit they have it, for fear of being labelled mentally ill or scaring off potential friends and lovers. But the chances are those friends and lovers have had similar experiences, too, for sleep paralysis (SP) is remarkably common.Various studies all over the world have shown that between 25 and 40 per cent of the general population have experienced SP at least once. One study in Japan - a country where much of the research has taken place - surveyed 8,162 people and found that just under 40 per cent had experienced SP. Thirty per cent of 870 university students surveyed by the psychology department of the University of Waterloo in Canada, another centre which takes an interest in sleep paralysis, had experienced at least one episode, and a recent survey at Goldsmiths College, London, showed that 40 per cent of a sample of undergraduates had had the experience at some stage.The 1990 International Classification of Sleep Disorders reports that sleep paralysis happens all the time to people with the sleep disorder narcolepsy, is a once or twice in a lifetime event for 40 to 60 per cent of the population, and is frequent in about three to six per cent of the rest of us. 


This means that in Britain, around 3m people could be experiencing once or twice a week what Dr Jones-Chesters endures every couple of months.'It's a very profound and frightening experience,' says Dr Chris French, a psychologist at Goldsmiths who specialises in the psychology of paranormal experiences and is collecting data on sleep paralysis. 


'People are very reluctant to talk about it, either because they think it really is an alien or nocturnal visitation, or because they think they are going mad. The truth is, though, that it's a very, very unpleasant experience, but certainly not indicative of any serious long-term psychological problems.'Sleep paralysis usually happens when someone is just entering or leaving sleep, and lasts from a few seconds to a couple of minutes. 


Most research has linked it with REM, or rapid eye movement, sleep which indicates dreaming. When the body and brain enter REM sleep, the muscles relax and the brain blocks signals that would normally allow the limbs to move, so preventing the body from acting out its dreams.


One suggestion for the cause of sleep paralysis is that the firewall between sleeping and wakefulness temporarily drops, so that some sleep phenomena, of which paralysis is one, breaks into wakefulness.'The connection with the environment switches on and the dream world off and you become self-aware and awake and wanting to go - and then you find you can't,' explains psychologist and pharmacologist Dr Chris Idzkowski, director of the Sleep Assessment Advisory Service. 'Which, in turn, is likely to lead to your being anxious and fearful.'But what about the visitations? Are they brought about by fear or are they dreams seeping into reality? If so, why are they always so gruesome? Why isn't Matthew Jones-Chesters visited by a magnificent angel?These questions have taxed Dr Al Cheyne from the University of Waterloo, one of the leading researchers into the phenomenon. He says recent evidence from neuroimaging studies during REM shows that the amygdala and several related limbic structures in the brain - the centre of our emotional being - are active during REM sleep. These structures are associated with instinctual responses, including fear, and what is called the 'threat-activated vigilance system'. This is thought to be activated by subtle cues for threat, which the system then attempts to corroborate by searching for further cues for danger. Such cues are especially active during anxiety dreams and nightmares and probably stimulate unpleasant memories, including culturally conventional images of threat, such as ghosts and aliens.'The fear of undetected threat is exacerbated because the person is awake, paralysed and usually in a helpless, supine position,' says Dr Cheyne. 'These are hardly circumstances to generate pleasant hallucinations. This throws up ghostly images. The conventional Grim Reaper and other hooded figures are popular - some people have even seen Darth Vadar.'Along with the hallucinations are feelings of being touched, pulled or a pressure on the chest. Some people even have out of body (OBE) experiences, though this is rare and often a sign of impending narcolepsy.Sarah, 25, had her first OBE experience when she was a student in Edinburgh. She now works with adults with learning disabilities and prefers not to reveal her surname. 'It just happened one night. I was falling asleep and my heart started pounding and I started floating upwards. I couldn't move. I was getting closer and closer to the ceiling, looking up, not down. I screamed inwardly to go down, and I did, but went straight through the bed, through the floor and down to the kitchen. It was incredibly frightening.'Once there was something awful and cloaked sitting on my armchair. Another time, I could see a pair of hands. All the time I thought there was something trying to get me, some deviant, awful thing trying to get me.'Sleep paralysis usually starts between the ages of 16 and 17. It increases dramatically through the teens and declines sharply during the twenties. It's comparatively rare after the thirties, but some people report episodes well into their seventies. 'You can't overlook the fact that adolescents are among the most sleep- deprived people in the population,' says Dr Cheyne. 'Sleep deprivation and disruption is a fairly effective way to increase the probability of sleep paralysis.'So common is sleep paralysis among shift workers that it is known as 'night-nurse paralysis', named not after the flu remedy, but the frequent reports of sleep paralysis among nurses doing night shifts. Lying on the back is supposed to increase the likelihood of an episode, but there is no link with anxiety, panic disorder or any other mental condition.There is, however, a genetic link. Akosua Serbeh-Baah, 20, a third-year psychology student at Goldsmiths and one of Dr French's students, suffers from sleep paralysis, as does her mother. Once you have experienced one attack, the fear that you might have another predisposes you to have more. Sufferers are consequently plagued by insomnia. But despite the unremitting nature of the condition, few sleep specialists take an interest in it, mainly because sleep paralysis, though debilitating, is essentially harmless. Few GPs, if any, have even heard about it.Consequently, those who live in terror of the night often keep quiet for fear of being labelled unstable. Sleep paralysis is one step away from mental health problems and for men, in particular, a sign that you can't deal with your sleep, as you should, along with everything else in your life.Dr Susan Blackmore, a research psychologist and visiting lecturer at the University of the West of England, carried out a large study between 1996 and 1999 of 'paranormal' experiences, most of which clearly fell within the definition of sleep paralysis. After she was interviewed on the radio about her findings, she was deluged with letters from grateful listeners. 'The most touching letter I got was from a young woman who said her boyfriend had asked her to marry him lots of times, but she didn't want to because she was afraid she was mentally ill. She kept getting this thing and she never dared tell anybody about it. Now she knew what it was and that it had a name and that it was perfectly normal, she was going to marry him.'Why the ignorance? 'It's transient, infrequent, never fatal and it's only rarely that people are affected by it,' explains Dr Adrian Williams, a consultant physician and director of the Sleep Disorders Centre at St Thomas's Hospital. 'Most GPs would refer these people on to a neurologist, or to one of the few sleep clinics.'But others, says Dr Blackmore, get referred to psychiatrists and misdiagnosed with mental health problems and prescribed drugs. 'This is tragic, because you don't need medication,' she says.This is not entirely true. Severe sleep paralysis can be treated successfully with Prozac-type anti-depressants which inhibit REM sleep, but sometimes the most effective way to deal with it is to understand what it is and develop techniques for waking yourself or your partner.'The vicious circle can be broken through by knowing what it is and being reassured that lots of people have it and you are not alone,' says Dr French.But for those with sleep paralysis, waking up is indeed hard to do. Akosua Serbeh-Baah manages to move a finger to flip her into wakefulness. Dr Jones-Chesters makes a noise in his throat in the hope that he'll bring himself round. It usually works.Sarah decided that she was going to have fun. Instead of her nocturnal wanderings along the cornices and through the floorboards of her Edinburgh house, she went to bed one night, determined to float around Scotland's magnificent capital. 'I decided this could be really cool and I could float around the city and enjoy myself. Of course, it stopped and I've never had it again.'· 


Dr Idzikowski's website, which gives general information on sleep disorders, is at www.neuronic.com. To contact the Sleep Advisory Service, phone 02892 622266.