Something is chasing you, but your legs feel cumbersome. It’s closing in, but you just can’t seem to move fast enough. Right when it’s about to catch you, you startle awake.
In the vestiges of those visions in your sleep, all you can think is, “What was that all about?”
The realm of dreams is fascinating, and slews of professions are dedicated to prying into every corner, from the origins of dreams to their functions, to the actual content our minds conjure every night.
It turns out nightmares, typically thought of as childhood plagues, can follow you even as you grow older. When you can’t seem to outgrow these dreams, or when you can’t manage to shake the frightening images returning week after week – what does it mean to have recurring nightmares, and is there a way you could avoid them?
What Is a Nightmare?
The simple definition of a nightmare is a negative dream, often resulting in the dreamer awakening in a startled or fearful state.
There’s two main types of nightmares, according to Michael Nadorff, an associate professor at Mississippi State University. There are post-traumatic nightmares or idiopathic nightmares. For idiopathic nightmares, their origins aren’t traumatic but their true sources for the dream are unclear.
However, even the thresholds for what’s considered a nightmare blur. Nadorff says, “It’s one of these things that nightmare nerds like me debate over.”
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Nightmares vs Bad Dreams: Understanding the Difference
The technical difference between a nightmare and, say, a bad dream is that you don’t awaken startled from the latter, he explains. But, whether that difference does exist, or if it matters, is uncertain.
“We get into this wonky debate of, well, maybe people just can’t differentiate [between the two]. But how different are they, really, if people can’t tell the difference?” he asks.
Nadorff personally believes that the two types of nightmares likely stem from the same phenomenon – they are a severe manifestation.
“But there are people that would disagree with me on that,” he says. “The actual, by-the-book definition is a nightmare would be a negative dream that leads to a startled awakening, but just know that bad dreams also exist, and they might be the same thing.”
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What Causes Recurring Nightmares?
The fascinating thing about dreams is how elusive they are to remember – even our dark and disturbing nightmares.
Francis Crick, best known for his Nobel Prize-winning DNA work, also studied sleep. He once floated a theory that, “We dream in order to forget.” He theorized that dreams could be our brain’s way of getting rid of accumulating false associations and excess information, thereby strengthening our existing memories.
Effectively, dreams were how our mind threw out the “garbage,” summarizes Rafael Pelayo, a sleep specialist at Stanford’s Sleep Medicine Center.
Since dreams tend to reflect our waking experiences and concerns, if we linger on them while we are awake, we could feed into an ongoing cycle of dwelling on an experience. We’re taking out the trash, thinking about it again, and bringing the trash back in to where it started. If we have a nightmare and dwell on it, it may return too.
“The fact that dreams are meant to be forgotten is the thing,” Pelayo says. “By dwelling on them, you’re just bringing them back into your head. That may be what recurring nightmares are about.”
Can Stress Cause Nightmares?
Periods of stress or emotional distress are also linked with recurring nightmares and anxiety is a major nightmare trigger.
For nightmares stemming from trauma, Nadorff adds they may also be a form of exposure therapy, the body’s attempt at healing and moving on from distressing events.
“But some people just get stuck in it, where they aren’t able to move on,” Nadorff says. “Because of that, they end up just getting tortured by their dreams.”
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The Body’s Role in Nightmares
Our bodies may also be responsible for recurring nightmares. If a patient approached Pelayo with nightmare troubles, he says his first question would be, “Why are you even aware of your dreams?”
Every night, we run through four to six sleep cycles. One cycle comprises of non-REM phases (which encompass drifting off to deep sleep) followed by the REM, or rapid eye movement, phase.
When Do Nightmares Occur?
Though dreams don’t exclusively occur during REM, we tend to experience our most vivid dreams then. Consequently, that’s when nightmares tend to manifest too.
After each of these sleep cycles, according to Nadorff, you awaken briefly – though not fully to the point where you’re aware of it. If you sleep through these cycles without fully waking up between them, you probably wouldn’t remember most of your dreams.
“If we’re not up for at least five minutes, we’ll never remember having it, because there’s not enough time to encode the awakening,” he explains. “So we know that there’s something about the need for being conscious to have memory.”
If you’re aware and remember your dreams – good or bad – then something may be fragmenting your sleep, according to Pelayo. Therefore, figuring out why you’re aware of your dreams in the first place is one way to address the issue. For example, sleep apnea is one sleep disruptor and can even spawn drowning or choking nightmares, due to breathing difficulties.
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How To Stop Having Nightmares
Maintaining a regular sleep schedule, on top of easing daytime anxiety, is helpful in any case. Losing hours of sleep can tip you into what’s called REM rebound, where your body attempts to restore balance by spending more time in REM – which could lead to more vivid dreams.
Nightmare Therapy
Another recommendation Nadorff emphasizes is seeking treatment. He is an expert in one particular nightmare treatment: image rehearsal therapy (IRT).
Patients using IRT re-imagine the outcome or narrative of their nightmares during the day, even if it’s just one scene – essentially rewriting the ending of their story when they go to sleep.
Lucid dreaming and practices like Exposure, Relaxation, and Rescripting Therapy (ERRT) – similar to IRT but especially well-suited for treating trauma – are other possible methods.
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Are Nightmares Normal?
While treatments like IRT have proven effective for alleviating nightmares, Nadorff suspects most aren’t aware they exist – or that nightmares are even treatable in the first place. He conducted a study in 2015 where he and his team asked college students and adults if they had discussed their nightmares with a healthcare professional before. They found a majority of individuals from both groups had never talked to a provider about their nightmares.
“I would get a fair number of these responses where people would say, ‘Well, I have nightmares every night, but doesn’t everybody?’” Nadorff says. “No, they don’t!”
We might not know yet what baseline “normal” is for nightmares, but, he adds, “If you don’t realize that what you’re experiencing is abnormal, you’re less likely to ask for help with it.”
Medication for Nightmares
While nightmares may render us feeling powerless in their midst, we have more control over them than we might think.
Many sleep physicians focus on treating sleep disorders like apnea, Pelayo says, but those board-certified in sleep medicine are equipped to handle nightmares. If anyone is struggling with nightmares, he encourages them to reach out to specialists.
“Modern sleep medicine has reached a point now where it’s unusual for patients not to get better,” he says. “My job as a sleep doctor is fun. Almost all of our patients improve. It’s unusual that I have somebody I can’t help.”
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