You’re falling, you’re being chased, you’re lost, you’re drowning… then you wake up, the nightmare lingering as you come back from it by degrees, trying to forget the scary dream that gripped you moments before and, hopefully, go back to sleep.
Suddenly, you scream and flail yourself around, and when you wake up, you’re disoriented and don’t know why. You’ve just experienced a night terror and you have no memory of what’s happened.
Both infect your sleep, both are jarring and create a deep sense of unease, and on the surface, they seem like they’re the same thing.
They’re not.
Same group, different experience
Ever heard of parasomnias? It’s this group of sleep disorders that includes sleepwalking (somnambulism), bed-wetting (sleep enuresis), and sleep talking (somniloquy). Nightmares and night terrors are also part of that group, and while they both evoke fear, how and why they do that and what they leave behind are unique.
Nightmares: dark, memorable dreams
The true definition of a nightmare is “coherent, realistic dreams that become more disturbing the longer you experience it.” They force you to wake up. While you may not always remember exactly what happened in the dream itself, you know why you were pushed out of sleep, and you recognize your rest was interrupted because you had a bad, dark experience while you slumbered.
You know the drill of what they feature — some sort of impending danger, a sense of doom, or disturbing themes that distress you. When we wake, the essence of the dream lingers and we are left with feelings of fear, embarrassment, and even anxiety. We know why we have those feelings even if we can’t recall what happened in the dream itself.
Nightmares come at us regardless of our age, although they’re most prevalent in kids ages 5-10. They may continue to show up from time to time when we get older — 50-85% of adults have periodic episodes of bad dreams — but their frequency tapers off. These are usually brought about by some sort of trauma, underlying fear or concern, or deep-seeded anxiety. We could go into the whole subconscious thing, but we’ll leave that for another time. You get our meaning. Nightmares come because something deep inside prompts them. The bottom line is those once-in-awhile dark dreams that jerk you awake as an adult are pretty normal.
Persistent and recurring nightmares, however, can interfere with sleep and are often a sign of severe trauma and post traumatic stress disorder (PTSD). They may also be caused by certain medications or anti-depressants, substance abuse, or medical, psychiatric, or sleep conditions. The time to reach out for professional help is when you find yourself dealing with frequent disturbing dreams. These not only cause sleep disruption, but emotional, mental, and physical duress.
Night Terrors: fear with no memory
Night terrors are episodes of screaming or flailing/agitated movement that’s accompanied by an intense, overwhelming fear. They can last anywhere from a few seconds to a few minutes, and only happen while you are asleep. These often are mobile, which means someone experiencing them is sleepwalking at the same time.
You don’t wake up because of night terrors. Sleep continues for the duration and it is traumatic to interrupt someone while they are in the middle of them. Because they tend to be moving around the room or house at the same time, it’s important to keep their path clear for their safety. If you try to restrain someone in the midst of their terror, they may lash out even more and become more agitated. What can work is to gently, calmly speak to the person without touching them, slowly bringing them back to themselves. More often than not, it’s better err on the side of caution and let them wake naturally while maintaining a safe space as they move around. Once someone does come out of their terror, they may be confused or even disoriented, but with no memory of the episode.
Children experience night terrors more than adults, usually growing out of them when they enter adolescence. There may be a genetic component because kids who come from a family with a history of these dark episodes are more susceptible to experience them as well. Pre-existing sleep apnea may also contribute to it. Just as persistent nightmares are cause for concern and an indication of underlying issues — not to mention destructive to your natural sleep cycle — consistent night terrors wreak havoc on your mind and body. If your child or you are constantly going through these, this, too, is the time to reach out to a medical professional.
NREM vs REM: the where and how of night terrors and nightmares
What truly distinguishes a night terror from a nightmare is where they live in our sleep cycle and what they leave behind. We’re going to get a bit science-y, technical on you with this but it will hopefully not only help you understand the difference but help you manage them if you or your children are experiencing both or either on a consistent basis.
The Five Stages of Sleep
Our sleep is split between 2 cycles: Non-Rapid Eye Movement (NREM) and Rapid Eye Movement (REM).
NREM has four stages:
Stage 1: Transition from waking to sleep
Stage 2: Light sleep
Stage 3 and 4: Deep sleep
Respiration and blood flow decrease during NREM while the body remains in a state similar to wakefulness. These stages are where night terrors, sleepwalking and sleep talking occur, hence the frequent combination of all three at the same time.
The fifth stage of sleep is where REM occurs. It’s here that the random, rapid eye movements happen, bringing about dreaming, and what is called REM atonia or a state of paralysis in the extremities. It’s where our bodies completely give over to true, unfettered restfulness. We usually fall into REM 90 minutes after we first fall asleep and throughout the rest of our slumber, we move between NREM and REM. It’s here we experience nightmares.
Now that we know about the stages and where night terrors and nightmares fall in the sleep scheme of things, let’s see how this contributes to what they make us feel.
Separation of sleep cycles
| NIGHT TERRORS | NIGHTMARES |
| Occur during NREM, usually Stage 3 in the first 3 hours of sleep | Occur later in the sleep cycle during REM |
| Upon waking, confused and disoriented | Upon waking, reorient yourself |
| No recollection upon waking | Wake with the memory of dreaming, even if not of the actual dream itself |
| NREM unrestricted movement and frequently accompanied by sleepwalking and sleep talking | REM atonia, natural sleep paralysis and no movement |
Similar, yes, but different as you can see. Sadly, these hit kids hardest, which can often lead to their being afraid to even go to sleep. Calm, gentle approaches to bedtime with children can help them at least face these fears with more ease. Again, if your child is consistently dealing with either of these, discuss options on how to alleviate or at least manage them with your pediatrician or a sleep disorder specialist.
Turning fear on its head
Maybe we won’t all experience night terrors and you may not still be having nightmares, but the world of sleep takes us through unique and unusual spaces in our mind. The level of impact your nightly rest has on every single aspect of your physical and emotional well-being is unfathomable.
You close your eyes, your breathing slows, and off you go to a whole other place to rejuvenate, refresh, and rebuild. Its value to our life is, well, everything. This import is why we need to give it the attention and care it deserves, and why building a better understanding of the different hurdles to a restful night helps us overcome them to get the slumber that truly benefits us.
Take your rest seriously, pay attention to persistent interruption and unease during it, and remember to ask for help if you need it.
You’ll sleep better.
