Patients will usually present with bouts of paralysis in periods before sleeping and before awakening. They are unable to move, speak and react in this transition which usually last for a few seconds to a few minutes. This paralysis spells conclude on their own or when the patient is touched or moved. The characteristic hypnogogic and hypnopompic hallucinations are often seen in sleep paralysis and are often revered as a terrifying experience in most patients.

• Falling

  This usually occurs as you're waking up, but can happen when falling asleep. [nhs.uk]

  The supine position was also 3-4 times more common during SP than when normally falling asleep. [ncbi.nlm.nih.gov]

  Medical attention may help when: sleep paralysis happens regularly there is anxiety about going to sleep or difficulty falling asleep the individual falls asleep suddenly or feels unusually sleepy during the day Suddenly falling asleep during the day [medicalnewstoday.com]

  You may feel the weight of some alien body pressing down on your chest -- or even kinesthetic sensations, such as feelings of being dragged from your bed, vibrating, flying or falling. [science.howstuffworks.com]

• Nightmare

  The overall response rate was 62.6%, and the prevalence of nightmares and sleep paralysis was 35.2% and 8.3%, respectively. [ncbi.nlm.nih.gov]

  Here's the teaser trailer for Rodney Ascher's The Nightmare, originally from Apple : The Nightmare is directed by Rodney Ascher ( Roomy 237 ). You are very tired. The pillow is soft. It’s late at night, and you start to drift off in your bed. [web.archive.org]

  When I wake up from a nightmare, I often find myself in a seated position. Or with my legs up. Or my arms up. It's because I jerk myself out of my nightmare. [topuniversities.com]

• Pain

  Another factor, Incubus, comprising pressure on the chest, breathing difficulties, and pain, is attributed to effects of hyperpolarization of motoneurons on perceptions of respiration. [ncbi.nlm.nih.gov]

  Sleep paralysis and “the bedroom intruder”: the role of the right superior parietal, phantom pain and body image projection. Med. [doi.org]

• Weakness

  It is most often due to prolonged compression of the radial (musculospiral) nerve, and, depending upon the site of nerve injury, is sometimes accompanied by weakness and extension of the elbow. [medical-dictionary.thefreedictionary.com]

  The Khmer ‘weak heart’ syndrome: Fear of death from palpitations. Transcultural Psychiatry, 39, 323 - 344. Google Scholar | SAGE Journals Hinton, D., Hsai, C., Um, K., & Otto, M. ( 2003 ). [doi.org]

  This causes the sudden bouts of unexpected sleep as well as temporary muscle weakness, another condition known as cataplexy. [scmp.com]

  If the patient is weak, let him have a generous diet, with wine, porter, bark, etc. Psoas Abscess. Symptoms. - A weakness across the loins, accompanied by a dull pain. [web.archive.org]

• Crying

  The hallucinations can also take the form of sounds like a loud bang or a child’s cry. These episodes frequently begin with a falling feeling followed by a “hypnic jerk” where the body’s muscles violently contract. [gotquestions.org]

  Cataplexy (a condition in which strong emotion like laughing and crying causes a person to physically collapse suddenly but remains conscious). [pyroenergen.com]

  I can’t cry for help. I can only breath heavily as fast as I can. Hoping someone will hear me breathing so loud and will come shake me out of it. I try and move a finger. Come on finger! Why won’t you just move?! It’s going to get me! [ Source ] 13. [thoughtcatalog.com]

  If you have ever woken up in the middle of the night and found you can’t move, or even cry for help, you have experienced sleep paralysis. [realitysandwich.com]

  SP episodes are generally accompanied by intense anxiety, inability to perform voluntary movements (even to scream or cry out for help), and, in some cases, fear of impending death ( Sharpless et al., 2010 ; Jalal and Hinton, 2013 ). [doi.org]

• Snoring

  Read Also: Why Do People Snore? Find Out What Causes Snoring How do I prevent sleep paralysis? Get enough sleep. Try to get at least six to eight hours of sleep per night. You can check out some tips to help fix your sleep schedule. [25doctors.com]

  Stress, sleep deprivation, alcohol and drug abuse are known to be the triggers, and it also can be linked to other sleep disorders, from snoring to narcolepsy. [thesleepstudies.com]

  Snoring in twins. Respir Med. 1995 May; 89 (5):337–340. [ PubMed ] [ Google Scholar ] Fredrikson S, Carlander B, Billiard M, Link H. CSF immune variables in patients with narcolepsy. [ncbi.nlm.nih.gov]

• Dyspnea

  For example, they associated dyspnea with near-drowning experiences during monsoon periods typical to Southeast Asia, or with their witnessing executions in which victims wore a bag over their head. [doi.org]

• Choking

  They may feel pressure or a sense of choking. Typically, this phenomenon is a symptom of narcolepsy. [nssleep.com]

  These include: sensing an intruder in the room – footsteps, voices, shadows etc a weight or pressure on the chest floating, levitation or out-of-body-experience sensation of being choked, strangled or sexually assaulted These hallucinations are most likely [sleepjunkies.com]

  Some people may also feel pressure or a sense of choking. Sleep paralysis may accompany other sleep disorders such as narcolepsy. Narcolepsy is an overpowering need to sleep caused by a problem with the brain's ability to regulate sleep. [webmd.com]

  You feel like you can’t breathe Part of what makes sleep paralysis so panic-inducing is that in addition to being immobile, many people feel like they can’t catch their breath or are choking. [rd.com]

  The individual's senses and awareness are intact, but they may feel as if there is pressure on them, or as if they are choking. It may be accompanied by hallucinations and intense fear. [medicalnewstoday.com]

• Muscle Weakness

  This causes the sudden bouts of unexpected sleep as well as temporary muscle weakness, another condition known as cataplexy. [scmp.com]

  Ask your doctor if this could be a possibility. [15] Other symptoms of narcolepsy can include hallucinations when you're falling asleep or waking up and cataplexy, which is sudden muscle weakness often brought on by strong emotions. [wikihow.com]

  weakness triggered by emotions). [ncbi.nlm.nih.gov]

• Visual Hallucination

  A modern manifestation of SP is the report of "alien abductions", experienced as inability to move during awakening associated with visual hallucinations of aliens. [ncbi.nlm.nih.gov]

• Delusion

  It pays to probe for the core experiences or events that patients may be explaining by devising "delusions". Acute, nocturnal-onset, first-time psychopathology warrants inquiry for sleep paralysis and hypnic hallucinations. [ncbi.nlm.nih.gov]

  Girard, Paranoid delusions and threatening hallucinations: A prospective study of sleep paralysis experiences, Consciousness and Cognition, 16, 4, (959), (2007). Todd A. Girard, Désirée L.M.A. Martius and J. [doi.org]

• Grieving

  Few pleasures can surpass that of comforting a grieving family with a near-perfect reproduction of their loved one as he was in life— why he looks almost alive, are the words that every undertaker treasures the most, and I longed to hear them once again [nightmare-magazine.com]

• Sleep Disturbance

  STAI-T >or= 75th percentile), and self-reported sleep disturbances. [ncbi.nlm.nih.gov]

  Keywords: sleep paralysis, parasomnia, sleep disturbance, REM sleep Oxford Scholarship Online requires a subscription or purchase to access the full text of books within the service. [oxfordscholarship.com]

  […] the treatment needs of a child with disturbed sleep. 50 This is a generally under-researched area and knowledge is very incomplete. [doi.org]

  When sleep paralysis causes severe sleep disturbance, a physician may order the following tests: Polysomnogram, an overnight sleep study measuring heart, brain and lung activity Electromyogram, a test showing muscle activity Multiple Sleep Latency Test [tuck.com]

• Screaming

  You stare at the blood, the jagged wound in her throat, her wide, staring eyes, mouth opened in soundless scream. You survived your Old Hag Syndrome. She didn’t. [creepypasta.wikia.com]

  "Every movement became impossible, and every scream was smothered by the plant material that was growing around his mouth and throat. [theguardian.com]

  I don't know what happened … I Try To SCREAM But Can't! [end-your-sleep-deprivation.com]

  And you can't even scream! This is sleep paralysis, a creepy but common phenomenon caused by an overlap in REM sleep and waking stages. [ed.ted.com]

  Unable to move, speak, or scream, the condition is often accompanied by vivid hallucinations. This is the condition Bruno suffers from, and when he first began to deal with it, he turned to the Internet for answers. [petapixel.com]

• Insomnia

  Abstract Sleep disturbances are important correlates of depression, with epidemiologic research heretofore focused on insomnia and sleepiness. [ncbi.nlm.nih.gov]

  It's not clear why REM sleep can sometimes occur while you're awake, but it has been associated with: not getting enough sleep (sleep deprivation or insomnia ) irregular sleeping patterns – for example, because of shift work or jet lag narcolepsy – a [nhs.uk]

  Sleep paralysis is also linked to: not getting enough sleep (sleep deprivation or insomnia ) or having regular disturbances to sleep such as shift work irregular sleeping patterns, for example those experienced by shift workers or students, or because [healthdirect.gov.au]

• Night Terrors

  Although sleep paralysis is terrifying and can happen at night, this condition is no relation to night terrors. The two are opposites, in a sense: in a night terror, you are asleep but moving around. [vitals.lifehacker.com]

  Night Terrors 00:19 5. Brain Fog 02:15 6. A Moment Of Clarity 00:32 7. Approached From Behind 01:37 8. Echoes Of The Past 00:39 9. Hallucination 00:55 10. Ancient Texts 00:49 11. Dysphoria 00:47 12. You Fall Off 00:56 13. [occasionallytapes.bandcamp.com]

  Sleep paralysis differs from dreaming and night terrors mainly due to the fact that the brain is awake, even if it hasn’t told the body just yet. “When people have a nightmare, they sleep, have a dream, and then wake up,” Bender says. [futurity.org]

  Sleep paralysis isn’t uncommon and it’s closely related to night terrors. Past theories about sleep paralysis have covered everything from hallucinations to evil spirts stealing your soul. [healthyway.com]

  Additional resources Cleveland Clinic Disruptive Sleep Disorders Fact Sheet Night Terrors Top Sleep Myths, Debunked [tuck.com]

• Confusion

  These views have resulted in confusion in the scientific literature on sleep paralysis with regard to its prevalence and core features. [ncbi.nlm.nih.gov]

  Often these images are of black smudges, which the confused mind interprets as human figures, sometimes called “shadow people.” The hallucinations can also take the form of sounds like a loud bang or a child’s cry. [gotquestions.org]

  That panic, that fierce attempt to move your limbs when it’s physically impossible, confuses your brain. So it tries to fill in the gaps by creating hallucinations of things like a presence in the room. [whyy.org]

  People between the ages of 14 and 25 are the most affected by sleep paralysis Irregular sleep patterns: All those late nights followed by early mornings followed by early mornings are bad for you and they’ll confuse your natural bodily functions such [howtolucid.com]

The diagnosis of sleep paralysis is reached when all other sleep disorders that potentially give rise to paralysis have been ruled out. The most common medical condition investigated upon with sleep paralysis is narcolepsy which actually includes sleep paralysis as one of its major diagnostic criteria. The following sleep study tests and diagnostic modalities are implored in the investigation of sleep paralysis:

• Nocturnal polysomnography: This device records the lung, heart, and brain activities during sleep. Breathing patterns are graphed while nocturnal patterns of arm and leg movements are also recorded. The blood oxygen levels are measured during the test process to assess the clinical impact of sleep paralysis or narcolepsy on the patient.
• Home sleep test kits: These test kits are very similar to the nocturnal polysomnograph, although only the heart rate, breathing patterns, airflow, and blood oxygen saturation are the only parameters which are being measured. Sleep experts may accompany the patient at home and makes a detailed observation of the sleep paralysis event. 

In the majority of patients suffering from sleep paralysis, treatment may not be required because it is clinically benign. For cases where the underlying causes are identified like the lack of sleep, some lifestyle modifications may be effected to increase the duration of sleep to avert the paralytic spells [8]. Patients having a mental health condition suffering from sleep paralysis may benefit from pharmacotherapy, psychotherapy, and family support that greatly reduces the incidence of the disorder. In severe cases of sleep paralysis, tricyclic antidepressants and selective serotonin reuptake inhibitors (SSRI) are commonly given to control the recurrence of the disorder [9].

Although the experience of sleep paralysis is adjudged to be most dreadful and terrifying to most subjects, there has been no scientific evidences linking it to serious medical events or disorders. Sleep paralysis has a good prognostic outlook for all cases.

Physiologically, muscles relax and becomes periodically paralyzed during normal sleep patterns. In some instances, these mechanisms of paralysis may temporarily persists during the transition of awakenings. Moreover, there are many events or risk factors that increase the likelihood for the development of sleep paralysis. Among these:

• Irregular sleeping patterns
• Sleep deprivation
• Teenager and young adults
• Narcolepsy
• Strong familial history

Among patients diagnosed with narcolepsy, 30 to 50% have experienced a form of isolated sleep paralysis [1]. Sleep paralysis has a worldwide incidence of 6.2% of the population, with any of them experiencing a paralytic attack of at least once a month or once a year. Of these patients, only 3% suffers from recurrent isolated sleep paralysis (RISP) which is a type of sleep paralysis that occurs nightly [2]. There is no sexual predilection in sleep paralysis. The adolescents and the young adult’s age group are more prone to sleep paralysis compared to any other age segments. The prevalence of sleep paralysis peaks at a mean age of 25 to 44 years old, representing 36% of all the cases recorded [3].

The researches done in sleep sciences have afforded several theories in the pathogenesis of sleep paralysis. The more common theories links sleep paralysis as a type of parasomnia or sleep walking which emanates from the dysfunctional overlap of the rapid eye movement (REM) stage of sleep and the waking stage of sleep [4]. Some current polysomnographic studies have made observations that any disturbances done in the regular sleeping pattern can induce sleep paralysis among its respondents [5].

Another major theory postulates that sleep paralysis stems out as a result of the neural signaling imbalances between the cholinergic neural populations that facilitates wakefulness and the serotonergic neural populations that maintains normal sleep [6]. The patterns of REM sleep fragmentations and the occurrence of hypnogogic and hypnopompic hallucinations among family lines have catered the idea that isolated sleep paralysis may involve genetic mechanisms in its pathogenesis [7].

Patients who are at risk of sleep paralysis may extend their sleeping hours to prevent its recurrence. One should avoid stimulants like alcohol, tobacco and recreational drugs that may alter one’s sleeping patterns. Patients are strongly advised to stay supine during sleep to reduce attacks of sleep paralysis and lessen the upper airway obstructions [10].

Sleep paralysis is a dreadful form of paralysis that clinically occurs upon waking up or just before going to sleep. Patients who undergone sleep paralysis complain of sensation of noise, olfaction, levitation and paralysis during the attacks. Sleep paralysis is not usually associated with a severe medical condition but the whole event will usually be frightening to the patient. Sleep paralysis occurs either before falling asleep which is also referred to as hypnogogic sleep paralysis or predormital sleep paralysis, or just before waking up otherwise known as hypnopompic or postdormital sleep paralysis.

Definition

Sleep paralysis is a dreadful and terrifying form of paralysis that periodically occurs upon waking up or just before going to sleep.

Cause

Sleep paralysis is commonly seen among the young adult population with high familial tendencies. Patients with variable sleeping patterns and those who have some form of sleep deprivation may also be prone to the disease.

Symptoms

The disorder occurs in the period just before sleeping or in the period just before awakening. Patients may be unable to move, speak, and react to any stimuli within a few seconds or minutes.

Diagnosis

Patients may offer a detailed medical history of the event at home. Sleep studies that makes use of the polysomnographs and the home sleep test kits may elucidate the disorder.

Treatment and follow-up

In majority of cases of sleep paralysis, treatment may never be required. Lifestyle modifications may be done to correct abnormal sleeping patterns. Medications like tricyclic antidepressants and SSRI’s may be given for severe cases of sleep paralysis.

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