Khyaak - The Demon Of The Dark

Here in Nepal, people often believe it to occur due to covering of the body by “Khyaak” when they have similar experience of sleep paralysis. “Khyaak” is a kind of ghost/demon that is believed to reside in the dark. Sleep paralysis is something of different cultures have constantly reported about for thousands of years. Different cultures at different parts of the world have different figures associated with such kind of experience. But is sleep paralysis really caused due to demon or is there some medical reason?

Medical Concept:

Medically, sleep paralysis is a neurology flaccid paralysis at sleep onset or on waking and in otherwise healthy person characterized by an inability to ‘kickstart’ the voluntary muscles, resulting in a transient ‘locked-in’ syndrome. It is associated with narcolepsy, Pickwick syndrome, sleep apnea, cataplexia and hypnagogic hallucinations. When considered to be a disease, isolated sleep paralysis is classified as MeSH D020188. When there is an absence of narcolepsy, sleep paralysis is referred to as isolated sleep paralysis (ISP). Cases of reported alien abduction are also commonly associated with this condition.

Alien Abduction Report may be a case of Sleep Paralysis

Your Concern:

An attack of sleep paralysis is usually harmless and self-limited. It tends to be over in a minute or two as soon as the brain and body re-establish connections and the person is able to move again.

Types:

a. Hypnagogic or predormital sleep paralysis: It occurs while you are falling asleep and as you fall asleep, your body slowly relaxes. Usually you become unaware of the change but if you remain aware while falling asleep, your motion and speech is ceased.

b. Hypnopompic or postdormital sleep paralysis: It occurs when you are waking up. During sleep, your body alternates between REM (rapid eye movement) and NREM (non-rapid eye movement) sleep. One cycle of REM and NREM sleep lasts about 90 minutes. NREM sleep occurs first and takes up to 75% of your overall sleep time. During NREM sleep, your body relaxes and restores itself. At the end of NREM, your sleep shifts to REM. Your eyes move quickly and dreams occur, but the rest of your body remains very relaxed. Your muscles are “turned off” during REM sleep. If you become aware before the REM cycle has finished, you may notice that you cannot move or speak.

Occurrence:

• Around 40% people experience sleep paralysis and is often noticed for the 1st time in teenage.
• In a research conducted, the responses of 80 1st year medical students, 16.25% had experienced predormital, postdormital, or both types of sleep paralysis.
• Most people experience sleep paralysis once or twice in their life time.

Symptoms:

• Paralysis: as described above
• Hallucinations: strange electrical noise (sound), pressure on chest, false sensation of someone standing by or moving, etc.

Causes:

• Lack of sleep
• Irregular sleeping schedule
• Sleeping in supine position (with face upwards)
• Sudden stress
• Sudden environmental/lifestyle changes
• Nacrolepsy
• Medications and alcohol

Treatment:

• Improving sleeping habits and avoiding chronic sleep deprivation
• Use of anti-depressants like clonazepam at night time and ritalin at day time
• Evaluation and treatment of nacrolepsy
• Preventing stress (Relieve yourself from stress)

Sources and sites for reference:

a. Various researches
b. WebMD
c. Wikipedia