Imagine that you’re at the end of a long night’s sleep. You find yourself in the same place you drifted off the night before and everything seems normal, as if you’re ready to get up and get started with your day—until you try to move. Nothing happens. You’re trapped in place, unable to move a muscle.
“It’s very scary and very frightening and extremely stressful,” says David Anderson, a 24-year-old freelance writer in Minneapolis who has had this experience repeatedly. “It’s always because of the idea that, you know, I’m completely unable to move. I’m very aware of that, so that’s where the stress and terror comes from.”
“In my head I believe I’m screaming,” he says. “Not in real life. I’ve never woken someone up because I’m screaming, but in my head what I can hear is me screaming or yelling. It’s not fun, man.”
Anderson first had the terrifying experience in 2010 when he was 18, the summer before he started his first year of college. After the same thing happened numerous times, Anderson did some light research and came to a self-diagnosis: he was suffering from sleep paralysis.
Sleep paralysis is just one of many sleep disorders known as parasomnias, characterized by abnormal brain functioning during sleep, which can result in some truly bizarre behaviors at bedtime. According to Michael Howell, M.D., a neurologist at the University of Minnesota and a sleep expert at the Fairview Sleep Center in Edina, parasomnias affect about 0.5 percent of the population. That’s 35 million people worldwide, or 25,000 people in the state
“Other studies have suggested that this number is too low, and if you look at people who are older than 60, you’re looking at somewhere between 4 to 6 percent of the adult population,” Dr. Howell says.
On Sept.11, 1982, Carlos Schenck, M.D., began his career in
He had been working at the Hennepin County Medical Center (HCMC) as a psychiatrist for about a year when he was informed that the center’s chief of neurology and head of the Minnesota Regional Sleep Disorders Center wanted to form a multidisciplinary sleep disorders center, and they needed a psychiatrist.
Dr. Schenck volunteered and began working with the team in September 1982. The second patient he met with, a 67-year-old man named Donald Dorff, had complained of having “violent moving nightmares.”
“After having a vigorous football dream ending with crashing into a bedroom dresser and gashing his forehead, he saw his doctor and then a psychiatrist, who both found no problem, and then he was sent to our center,” Dr. Schenck says.
The case was particularly strange because Dorff had never been a sleepwalker before, and his behavior went beyond simply getting out of bed and walking around. Five nights after meeting him, Dr. Schenck and his colleagues studied Dorff in their sleep lab. “Lo-and-behold, he demonstrated something never before documented in humans. He had lost the normal and protective paralysis of [rapid eye movement (REM)] sleep, and was jerking and twitching his limbs and sitting up, throwing punches, kicking while dreaming.”
The doctors at HCMC had discovered a new sleeping disorder: REM sleep behavior disorder, or RBD. It was the first of what would become a long list of strange parasomnias.
The World of Parasomnias
It is well-known that we don’t always sleep perfectly. Insomniacs find it difficult to fall asleep or remain sleeping throughout the night.
Many people are afflicted by sleep apnea, which makes it difficult or even impossible to breathe steadily while sleeping. There are even disorders like narcolepsy, where a sufferer will spontaneously fall asleep while going about their normal business.
But parasomnias represent some of the strangest examples of how sleeping can take a left turn.
Imagine waking up and finding out that your kitchen had been raided the night before—by no one other than yourself. Picture your bed partner talking to you about sex you had initiated—while you were asleep.
Or imagine watching a Spider-Man movie and then dreaming that you’re the web-slinger himself—except that in reality you are a naked college student who jumps out of your window and breaks your wrist.
That last case was one seen by Dr. Howell in his own practice.
According to Dr. Howell, “parasomnias are abnormal behaviors that occur during sleep or the transition into or out of sleep. They’re divided into two categories: parasomnias associated with REM sleep or parasomnias associated with non-REM sleep.”
Rapid Eye Movement sleep, or REM sleep, is the deep state of sleep during which individuals dream most vividly and is characterized by random movement of the eyes. During REM sleep, the body undergoes a self-inflicted atonia, or paralysis of the muscles. This keeps individuals from acting out the behaviors that they are experiencing in their dreams. But when that atonia fails, you see what Dr. Schenck first saw in the “moving nightmare” case of Donald Dorff: REM sleep behavior disorder.
A failing of the usual paralysis related with REM sleep causes RBD, and Anderson’s parasomnia is the result of the opposite.
“Sleep paralysis is a preservation of normal REM atonia, normal REM paralysis into wakefulness,” Dr. Howell says. “So people are still paralyzed and they wake up but they’re frozen, they feel like they can’t move, they can’t scream.”
Due to the semi-sleeping state during which sleep paralysis occurs, sufferers may experience strange things in their bedrooms. Some have visions of someone else in the room. Others experience a sense of a sinister, almost paranormal presence near them. But the terrors of sleep paralysis aren’t limited to the time after waking.
“I dreamt that I was in my parents’ then car and I was driving it and was slow motion like going toward a tree but couldn’t move my body so I had no ability to hit the brakes,” Anderson says. “I initially dismissed it as just a really weird, stressful nightmare.”
In fact, it was just a slightly different episode of the same bizarre phenomenon he has experienced repeatedly.
“Any time you have a dream where you have trouble moving, that’s actually sleep paralysis,” Dr. Howell says. “It’s that same awareness of inhibited motor skills.”
More Than Sleepwalking
While it may be terrifying to consider the realities of abnormal REM sleep atonia, like jumping out of your own window or feeling trapped in bed, non-REM sleep parasomnias include some pretty bizarre cases as well.
These parasomnias, “in particular sleepwalking, [are confusional arousals] that occur because the brain fails to wake up completely and people wake up in a disoriented state and they start ambulating,” Dr. Howell says. “During non-REM parasomnias you can do very complex behaviors, including sleep driving, sleep sexual activity, sleep related eating.”
Sleep related eating disorder, or SRED, is another parasomnia that Dr. Schenck has studied in his career. “In SRED, patients would eat cat food sandwiches, butter cigarettes, put napkins in a toaster and then eat the burnt napkins, eat spaghetti and meatballs bare-handed, put coffee grounds with Coca- Cola and raw eggs in a blender and then turn on the blender and drink the horrible concoction,” Dr. Schenck says.
Sexsomnia, something Dr. Schenck calls another “appetitive” parasomnia, illustrates how parasomnias can affect people other than the sufferers of the disorder themselves. “There is a full range of sexuality emerging from sleep that can disturb the sleep of the bed partner, and which can cause all sorts of medical morbidity, such as from violent masturbation, and interpersonal problems,” Dr. Schenck says.
Dreaming of a Cure
However whimsical or weird some parasomnias seem, there may be a much more significant reason for studying them.
Dr. Howell says he first became interested in studying parasomnias when he learned about their connection to neurodegenerative conditions like Parkinson’s disease.
“If somebody does indeed have REM sleep behavior disorder, or violent dream enactment, that is nearly universally caused by some degree of a pathology of the brainstem that controls the REM sleep circuits and this pathology is typically early neuropathology associated with Parkinson’s disease or conditions like it,” Dr. Howell says.
In other words, the same problems in the brain that cause RBD cause Parkinson’s.
“Thus, it’s very important for us to study and understand this condition because… hopefully by understanding REM sleep behavior disorder and the processes that lead to Parkinson’s disease, we can prevent them. Our ultimate goal is to help prevent and cure Parkinson’s disease with these studies.”
For Anderson, realizing that his waking nightmares were in fact sleep paralysis was the first step to improving his sleep.
“I think when something happens to you enough you’re able to start developing patterns and ways of dealing with it,” he says. “Am I able to move my arms and am I able to open my eyes and look around or can I move my head? If the answer is no, I can sort of calm myself and say all right, this means you’re dreaming.”
For others, especially those at risk of Parkinson’s disease, awareness of RBD may lead to a doctor’s visit. Dr. Schenck believes that sleep science is sufficiently recognized but believes that there needs to be more understanding of the significance of parasomnias.
“Better medical student education and more [continuing medical education] courses to educate practicing physicians, along with media exposure of all types can help raise further awareness about parasomnias,” he says.
“Many people when they have these conditions don’t know where to go,” Dr. Howell says. “Family members will often think that that’s just the way grandma is and there’s nothing to do about it, but in fact there is something very much wrong with grandma or grandpa if they’re doing this sort of behavior, and it can be identified