Over a year ago, a friend told me a story that chilled me to the bone. She described a situation in which she was falling asleep and heard a noise from the direction of her closet.
She tried to turn and found herself paralyzed, but her eyes could see her open closet. As she stared, she realized two glowing red orbs, eyes, were staring back at her. She tried to scream, found she couldn't, and then the thing attacked.
It leapt upon her bed, smother her. For several terrifying seconds, she heard it's raspy voice, smelled it's putrid breath, and felt the weight of it on her chest, all the while unable to move. Eventually, it ended, leaving her so shaken with fear she didn't sleep for two nights.
Upon doing some reading on the Internet, she discovered she wasn't alone and the thing she experienced was a hag. In the paranormal world, it's known as a mara experience (mara derived from mare, an Old English word for a demon, which is also where the word nightmare comes from). The scientific world calls it sleep paralysis.
Whatever the cause, many experience something similar. There's been research into this type of experience in recent years. While there's much more to learn, science describe it as an area of sleep between awake and deep sleep. Research has shown that during REM sleep (when we dream), the brain sends transmitters to our bodies that target our muscles to 'shut off' so that we don't act out our dreams in the physical sense. Those who experience sleep paralysis enter this stage, but then their consciousness awakens, leaving their muscles in this dormant state, hence the paralysis.
In effect, they're still dreaming, so depending upon their fears, their nightmares become reality in a type of hallucination. Because of the awareness and paralysis, naturally a person panics. At least, this is the explanation that science offers, which makes sense to a degree.
There's still unanswered questions. The hag is not the only manifestation out there. People have reported vampires, aliens, dark shadows, and poltergeists. Some have no idea what's in the room with them. They can only sense an evil entity, but it remains out of their field of vision due to the paralysis.
What doesn't make sense, and the reason some refuse to accept the common medical explanation, is the very real after-effects. For example, the person attacked by a vampire may go to the mirror and find two puncture wounds in their neck. Those who experience an alien may find their bodies sore in places that later expel metal shards, as if from implants. And in the case of my friend, if they've been hag-ridden, they may find a variety of bruises and scratches from the attempted stangulation or suffocation.
Such discoveries seem to thwart an easy explanation, yet modern medicine still tries. The claim is that the experience is so real, the body reacts in a very real way, brought on by the powers of the mind. For example, blood vessels in the neck may break and bleed due to the strong belief in the vampire attack. Why is this mind-over-matter idea more viable than the possibility of a real attack?
Around the world, similar attacks happen, and they have for centuries, and it has roots in everyday language. Have you ever seen someone really tired-look and tell them they look haggard? This derives from the Old Hag, which many blame rather than the sleep paralysis.
In fact, some accuse Lilith of being the hag. There are stories that prior to Eve, Lilith was created for Adam, but because she refused to lay on her back for him, she was replaced with someone more suitable -- Eve. She's said to have the power of flight, and when she was thrown from Eden, she flew away, but still returns to seek revenge from unsuspecting persons.
Like so many things, we may never have an explanation that fits all the puzzle pieces together. Until then, many people can't disclude the possibility that these attacks are from otherworldly beings of some sort, my friend included.