One night in July 2016, I woke up in a cold sweat. A hooded man was standing over me. His face was only about a foot away from mine. There was a handkerchief covering his entire face and head, tied around his neck like a sack. It was purple silk with a yellow paisley pattern, I can still picture it clearly.

The man and his handkerchief were both a hallucination. I hadn’t been dreaming about anything in particular, but when I woke up and opened my eyes, I saw him standing there, leaning over the bed. He stayed above my head, three-dimensional and opaque, for about a minute after I woke up.

Naturally, I was screaming the entire time.

That night, there was someone else in the room to tell me that what I was seeing wasn’t real. The next few times, I wouldn’t be so lucky. The next morning, we looked up what had happened to me, and were able to figure out that I’d had my first night terror.

Night terrors affect only 5% of adults — they’re more commonly experienced by children. They aren’t something you can wake up and brush off, like you would a nightmare. Often, the hallucinations brought on in a night terror appear entirely real, and adults who experience night terrors can see whatever it is for several minutes after waking up.

“Night terrors are a largely misunderstood and neglected parasomnia,” writes George Dvorsky for Gizmodo. “Much of this has to do with the fact that it’s a very challenging condition to study and that it’s often confused with nightmares. But the only similarities between the two is that they happen during sleep.”

The condition is not unlike sleep paralysis in many ways, but the main difference is that during a night terror, you’re able to move — though this may not work in your favor. Those who experience night terrors have been known to react violently to their hallucination, often by screaming, but people even run out of the house in the middle of the night, convinced their home is being raided by demons or ghosts.

For this reason, night terrors have even been used as a defense in murder cases. People convicted of stabbing or strangling whoever was sleeping next to them claimed they were hallucinating a monster attacking their loved one. I’ve never done anything in response to a night terror but scream, but thinking about it does always make me feel glad I currently live alone.

My night terrors aren’t the same thing as sleepwalking, in that I can remember what I saw and how I reacted clearly; I sleepwalked once, as a kid, but I did feel like I was asleep, because I woke up in my parents’ room without any memory of getting there, and then I returned to my room, again with no memory of walking back. But during my night terrors, I feel very much awake. My eyes are wide open, and I can perfectly register all of the other, non-hallucinatory details about the room I’m in.

I experienced my second night terror less than a month after the first, while visiting family in Chicago. I woke up in the middle of the night and saw a man standing at the foot of the bed, staring directly at me. At the time, I was somehow certain he was a rapist, but I didn’t think I’d ever seen him before. I saw him for a few minutes before a family member came into the room to make sure I was okay.

Like the previous hallucination, I still vividly remember what he looked like. Much later on, I suspected I had, in fact, seen him somewhere before, and did some Googling to find that he was one of the convicted in a widely-covered rape case from a few years before the time of my night terror. I didn’t remember ever paying much attention to his face while seeing stories about the case, but there he was in the mug shots, exactly as he had appeared in my hallucinations, so I can only assume that my subconscious had tucked it away somewhere.

That summer, I couldn’t figure out why this was happening to me. The fact that I’d never experienced night terrors before, and that they were occuring in tandem with regular nightmares, suggested there was some direct cause. I suspect it was the stress I was feeling at the time around my upcoming move to India, but to this day, I still don’t know why I’d never had night terrors when I’d been stressed before.

Very little is known about night terrors, and even less about why they happen. According to Healthline, “the cause of night terrors is often unknown, but the condition may result from lack of sleep or high levels of stress.” Contributing factors are believed to range from depression and anxiety to alcohol consumption. They’re also thought to be triggered by other sleep disorders, like sleep apnea and restless leg syndrome, and prescription drugs that alter your sleeping pattern, like antihistamines and antidepressants.

In general, adults seem to forget what they see during their night terrors by the next morning, although others, like myself, have a clear image of what they saw. I’ve never given much thought to my strongly visual sense of memory, but it certainly could explain why I’m able to remember my night terrors, and why the hallucinations are sometimes exact matches of images I’ve seen in the past.

Immediately after I moved to India, I woke up to see a shadowy girl with long black hair sitting on my bed. I put it down to my difficulty adjusting to the move. Since no one was home that night to convince me she was a hallucination, I kept the lights on and read a book to try and make myself forget about it, but needless to say, I didn’t get much sleep.

It happened again, a few months later, at my grandmother’s house in Kolkata. By this point, I was an old hat at the night terror game, and felt noticeably calmer in face of possibly the most frightening hallucination yet: a broad-shouldered, long-haired, mustachioed man holding a golden club. I didn’t even scream. We stared at each other mildly for a few seconds, and then, after I blinked a few times, he vanished.

This time, I knew who he was right after I stopped hallucinating him: Yama, the god of death. I wasn’t raised particularly religious, so I’d only seen an image of him once, when I was a little kid, in one of those educational Hindu comic books. I didn’t even own the comic — I’d flicked through it at the bookstore out of curiosity, and had barely thought of it since. But my memory had held onto it, and when I Googled Yama to verify, he looked just as he did in my hallucination.

It has been surprisingly easy to fight the instinct that Yama was some sort of omen — my grandmother passed away very suddenly a month later — perhaps because he wasn’t an isolated incident. That is, ultimately, the most reassuring fact about night terrors. It’s been almost two years since I had my first one, and in that time, out of sheer necessity, I’ve become adept at calming myself down after them.

Healthline suggests different kinds of therapy to help manage night terrors, such as Cognitive Behavioral Therapy or even hypnosis. (I saw a hypnotherapist recently and couldn’t be more emphatic about how unhelpful it was.) I did talk to a few psychotherapists about my night terrors, but they were only able to help me in the way they help patients with regular nightmares, by asking if anything had been causing me stress and if I’d been sleeping regularly. I haven’t spoken to a doctor or psychiatrist, but I know it’s an option if the night terrors ever become unbearable; prescriptions for certain antidepressants, benzodiazepines, and even Valium can help.

Weirdly, the most comforting thing has been to identify the pattern, and remind myself that this is probably an indication of my highly visual memory and a poor quality of sleep, more than it is a sign of paranormal activity. It helps to know others experience it too, even if it’s only 5% of us. (I’m not ashamed to admit that learning Kirk from Gilmore Girls gets them also has helped considerably.) Night terrors have even been beneficial on occasion, because now, after I have one, I force myself to evaluate any overlooked problems in my life that might be causing me more stress or discomfort than I’d realized.

A few weeks ago, I woke up to find a sort of demon Red Riding Hood (with a black hood, no face) crouched by my nightstand. I got up, fetched myself a glass of water, and slept with the lights on that night. The next day, I was able to think nothing of it, beyond being impressed with my imagination for dreaming up such creative imagery.