5 Sleepless Facts About Nightmares and Other Parasomnias

Everyone will have bad dreams at some point (or many points) in their lives. They can range from uncomfortable to horrifying to downright dangerous. Some bad dreams are severe enough to be considered parasomnias, or sleep disorders. Here's a glimpse at what some of the most unsettling parasomnias have in store for the people who experience them.


A nightmare is indeed a bad dream, but not all bad dreams are nightmares. Specifically, a nightmare is a dream with a vivid and disturbing plot that most often wakes the dreamer from their sleep. Upon waking from a nightmare, a person may be sweaty, out of breath, and feel afraid. A bad dream, on the other hand, is simply a non-medical catchall term for dreams that are unpleasant.

Nightmares take place during the final and deepest phase of sleep (rapid eye movement, or REM), when the brain shuts off communication with the spinal cortex, causing our limbs to be temporarily paralyzed for sleep. Research has linked PTSD, anxiety, and certain medications to nightmares in adults. Nightmares can also be caused by eating before bed. Eating triggers a metabolic response and increases the brain’s activity, even during sleep.


Frequent nightmares among children ages 5 to 12 are pretty common, affecting 20 to 30 percent of kids, according to the American Academy of Family Physicians. Nightmares most often taper off as children reach adolescence though, so in adults, frequent nightmares are somewhat rare: Only about 5 to 8 percent of adults will experience frequent nightmares, and generally only certain personality types will have this experience.

Overall, adults who are most likely to suffer from frequent nightmares are those who are "creative" (those who on psychological tests, as this sleep study says, are more likely to reject rigid understandings of the world and interpret life in shades of gray), or might have an underlying psychological problem. A 2015 study of Finnish adults found that adults who deal with depression, exhaustion, and insomnia are much more likely to have nightmares. Another study from 2009 demonstrated a link between anxiety and increased nightmares for women. This same report found that adult women are more likely to experience nightmares than men.


Anyone who has had sleep paralysis knows how terrifying an experience it can be. The sleeping person’s mind is essentially awake, but the body is immobile and in a state of sleep (hence “paralysis”). Sleep paralysis only occurs in stages of light sleep and is most likely to happen during a nap or close to the end of a night’s sleep. A person will experience visual and auditory hallucinations that are universally fearsome in content. The body is unable to move during an episode of sleep paralysis, making the experience all the more surreal and terrifying. Neurobiologists have found evidence suggesting that the paralysis experienced during sleep paralysis could be caused when shifts between REM stages don’t happen as they should, resulting in a brain that is awake and a body that remains asleep.

A very common sleep paralysis hallucination is of a demon sitting on the chest of the sleeper; it's often accompanied by the sound of whispers, train horns, or bells. Across cultures, hallucinations that result from sleep paralysis involve an intruder that is perceived as a threat, whether it's the succubus of medieval Europe, the Old Hag of Newfoundland, the alien abductor of America, or the Batitat of the Philippines.


Night terrors are a whole other level of body and brain activity that are highly disturbing—but unlike nightmares, night terrors don't awaken the sufferer, despite manifesting as an extreme experience. During a night terror, a person might thrash, scream, or yell, have open eyes, and be extremely difficult to awaken. It’s also not uncommon for someone in the throes of night terrors to physically act out, which could be very dangerous if the person were to leave bed or the home while still asleep. Night terrors are not dreams, per se, but the result of a malfunction in the brain that occurs when the sleep stage moves from light to REM sleep.


One of the most unsettling forms that dreaming can take is REM behavior disorder (RBD). Brought into the mainstream by comedian Mike Birbiglia’s 2012 film, Sleepwalk With Me, RBD is present when sleeping people act out the narrative of their dreams, which is likely to include risky behavior (such as jumping out of a closed second-floor window, as Birbiglia did). The experience of RBD is similar in some ways to night terrors, but the content of RBD dreams will be generally involve a lot of action—running, jumping, playing sports—and its manifestations can be violent.

As the name suggests, RBD occurs during REM sleep and is commonly associated with disorders such as sleep apnea, narcolepsy, and periodic limb movement disorder. When a person suffers from RBD, typical muscle atonia does not occur during deep sleep, which results in physical action. It is not uncommon for sufferers to hurt themselves—or anyone they share a bed with.

Any of this ring a bell? Check in with your doctor. The occasional nightmare isn’t cause for concern, but a doctor will want to know about any sleep disorder behavior that persists—or causes injury. But if you’re in the majority of fortunate adults who have pleasant dreams without incident each night, continue to sleep tight!

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6 Historical Methods for Contacting the Dead (and Their Drawbacks)
Hulton Archive/Getty Images
Hulton Archive/Getty Images

'Tis the season for getting in touch with the spirit realm. (This applies no matter what month we're in right now; 'tis always high time to get your séance on.) But there are several different ways you can go about it. Do you Ouija? Should you go wandering around a haunted house? No, you should probably pick up the psychic telephone.

Lapham's Quarterly helpfully charted out some of historical ways you could (supposedly) go about contacting the dead, from Chinese Fuji writing—a method that's kind of like a Ouija board, but using a stylus to make letters in sand instead of a board—to past-life regression via hypnosis. The chart lays out how each ghost-whispering concept works, and its theoretical drawbacks. Because there are always drawbacks.

Transfiguration, for instance, lets you see a spirit's face through the body of a medium, but that's a whole lot of hard work for your medium. You can listen for electronic voice phenomena via a recorder, but you have to buy the recorder first. F. R. Melton's 1921 invention, the balloon-powered psychic telephone, was a great option—except when his son George wasn't around to work it. And past-life regression, as you might imagine, holds “potential for new levels of self-hatred." No one wants to find out that their past self was a total jerk.

There are plenty of scientific and cultural explanations for seeing ghosts that don't involve the actual spirits of the dead returning to the Earthly plane, but if you're into the history of the occult, this is a great primer on spirit-conjuring traditions.

[h/t Lapham's Quarterly]

Michael Tackett - © 2012 Warner Bros. Entertainment Inc. All rights reserved.
9 Horror Movies Inspired by Real-Life Events
Michael Tackett - © 2012 Warner Bros. Entertainment Inc. All rights reserved.
Michael Tackett - © 2012 Warner Bros. Entertainment Inc. All rights reserved.

While most horror movies are complete works of fiction, the genre occasionally offers up stories that are based on terrifying and jaw-dropping real-life events, like the nine collected here.


Premise: A supernatural killer stalks his prey while they dream during deep sleep. 

Real-Life Inspiration: Wes Craven based A Nightmare on Elm Street on a series of newspaper articles from the Los Angeles Times about a strange phenomenon where young Asian refugees would mysteriously die in their sleep. It was reported that many would refuse to sleep, citing terrifying nightmares that they feared would lead to death.

According to Craven, the paper "never correlated [the three articles], never said, ‘Hey, we’ve had another story like this'":

The third one was the son of a physician. He was about twenty-one; I’ve subsequently found out this is a phenomenon in Laos, Cambodia. Everybody in his family said almost exactly these lines: "You must sleep." He said, "No, you don’t understand; I’ve had nightmares before—this is different." He was given sleeping pills and told to take them and supposedly did, but he stayed up. I forget what the total days he stayed up was, but it was a phenomenal amount—something like six, seven days. Finally, he was watching television with the family, fell asleep on the couch, and everybody said, "Thank god." They literally carried him upstairs to bed; he was completely exhausted. Everybody went to bed, thinking it was all over. In the middle of the night, they heard screams and crashing. They ran into the room, and by the time they got to him he was dead. They had an autopsy performed, and there was no heart attack; he just had died for unexplained reasons. They found in his closet a Mr. Coffee maker, full of hot coffee that he had used to keep awake, and they also found all his sleeping pills that they thought he had taken; he had spit them back out and hidden them. It struck me as such an incredibly dramatic story that I was intrigued by it for a year, at least, before I finally thought I should write something about this kind of situation.

2. CHILD'S PLAY (1988)

Premise: A serial killer's soul possesses a toy doll and wreaks havoc.

Real-Life Inspiration: In 1909, Key West painter and author Robert Eugene Otto claimed that one of his family's servants placed a voodoo curse on his childhood toy, Robert the Doll. Supposedly, the doll would mysteriously move from room to room, knock furniture over, and conduct conversations with Otto. Robert the Doll was left in the attic until Otto's death in 1974, when new owners moved into his Florida home. The new family also claimed mysterious activities would happen in the house connected to the doll. Today, Robert the Doll is on display at the Custom House and Old Post Office in Key West, Florida.


Premise: A young family moves into a house where a murder was committed, and experiences strange and terrifying occurrences.

Real-Life Inspiration: Based on the book of the same name, The Amityville Horror follows the paranormal events that terrorized the Lutz family. In 1975, the family moved into 112 Ocean Avenue where, unbeknownst to them, Ronald DeFeo, Jr. had brutally murdered his family 13 months before they arrived. While in their new home, the family claimed that they saw green slime on the walls and red-eyed pigs staring into their kitchen and living room. After less than a month, the Lutz family moved out of the small town of Amityville, New York.

4. PSYCHO (1960)

Premise: A secretary goes on the run after she steals $40,000, only to wind up in a motel where the innkeeper and his mother are more than they appear to be.

Real-Life Inspiration: Psycho's Norman Bates is loosely based on convicted murderer and grave robber Ed Gein, who, during the late 1950s, killed women and unearthed corpses in Wisconsin. He also fashioned human skin into tiny keepsakes and knickknacks, such as face masks, belts, and chair coverings. Psycho's novelist Robert Bloch based Bates on Gein, but changed the character from a grave robber and murderer into a serial killer who dressed like his mother. The Texas Chainsaw Massacre and The Silence of the Lambs also based their serial killers—Leatherface and Buffalo Bill, respectively—on Gein.

5. THE EXORCIST (1973)

Premise: Two Catholic priests perform an exorcism on a young girl who is possessed by the devil.

Real-Life Inspiration: The Exorcist's author and screenwriter William Peter Blatty based the novel and film on a Washington Post article from 1949 headlined, "Priest Frees Mt. Rainier Boy Reported Held in Devil's Grip." The article followed Jesuit priests William S. Bowdern, Edward Hughes, Raymond J. Bishop, and Walter H. Halloran participating in the rite of exorcism on a boy with the pseudonym "Roland Doe" in Maryland. According to the priests, they allegedly experienced the boy speaking in tongues, the bed shaking and hovering, and objects flying around during the ordeal. The exorcism was one of three official Catholic Church-sanctioned exorcisms in the United States at the time.

"Maybe one day they’ll discover the cause of what happened to that young man, but back then, it was only curable by an exorcism," William Friedkin, the director of The Exorcist, told Time Out. "His family weren’t even Catholics, they were Lutheran. They started with doctors and then psychiatrists and then psychologists and then they went to their minister who couldn’t help them. And they wound up with the Catholic church. The Washington Post article says that the boy was possessed and exorcised. That’s pretty out on a limb for a national newspaper to put on its front page ... But you’re not going to see that on the front page of an intelligent newspaper unless there’s something there."


Premise: An aunt tortures and abuses her niece, and a neighborhood boy fails to alert the authorities.

Real-Life Inspiration: Based on Jack Ketchum's novel of the same name, The Girl Next Door is based on the murder of Sylvia Likens, a 16-year-old girl from Indiana in 1965. Sylvia and her sister Jenny were left in the care of Gertrude Baniszewski, a family friend, when their parents left town as traveling carnival workers. Baniszewski, along with her children and a few neighborhood kids, locked Sylvia in the basement, where they tortured and abused her until she died of a brain hemorrhage and malnutrition.


Premise: Two paranormal investigators help a family who move into a secluded home plagued by weird events.

Real-Life Inspiration: The Conjuring is based on real-life paranormal investigators Ed and Lorraine Warren and their experience with the Perrons, a family who moved into a Rhode Island farmhouse and experienced ghostly and terrifying occurrences in 1971.

"When Insidious came out and was successful the story about the Warrens came to me and I was like, 'Oh, my gosh, this is really cool,'” director James Wan told Entertainment Weekly in 2013. "But I didn’t just want to make another ghost story or another supernatural film. One thing I had never explored was the chance to tell a story that’s based on real-life characters, real-life people. So those were the things that led me to The Conjuring."

The Warrens also had a possessed Raggedy Ann doll that was the inspiration for the spin-off film Annabelle. Allegedly, a demon spirit possessed the Raggedy Ann doll, which is currently on display and under lock and key at the Warrens' Occult Museum in Monroe, Connecticut.

8. OPEN WATER (2003)

Premise: Two scuba divers become stranded in shark-infested waters after their tour group accidentally leaves them behind.

Real-Life Inspiration: Open Water is based on American tourists Tom and Eileen Lonergan, a couple who were lost at sea when their tour group left them behind while scuba diving near the Great Barrier Reef in Australia in 1998. When the diving company realized the mistake two days later, they organized a search party, but the Lonergans were never found. The only thing that was found was a diver's slate (an underwater communication device) with a S.O.S. message on it that read, "[Mo]nday Jan 26; 1998 08am. To anyone [who] can help us: We have been abandoned on A[gin]court Reef by MV Outer Edge 25 Jan 98 3pm. Please help us [come] to rescue us before we die. Help!!!"

9. THE BLOB (1958)

Premise: A mysterious alien life-form terrorizes a small town and consumes everything in its path as it grows bigger and bigger.

Real-Life Inspiration: Believe it or not, The Blob is based on a New York Times article from 1950 titled, "A ‘Saucer’ Floats to Earth And a Theory Is Dished Up." The story followed four Philadelphia police officers who came into contact with a strange gooey material, which is now believed to be "Star Jelly," a transparent gelatinous substance. When one of the officers tried to move the goo, it started to dissolve and evaporate, so there was nothing to show the FBI when they arrived on the scene except a spot on the ground.


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