Apparently, you can dream in any stage of sleep, but REM sleep is the point at which you have the most vivid dreams. It is also what your brain tries to catch up on first when you haven’t been getting enough sleep.
Eventually, if you don’t catch up on dream-sleep, you get daytime hallucinations. I’ve gotten these. When I have slept particularly badly for three days or so, I start to see people in my periphery who aren’t real. I know they aren’t real, and are just my brain trying to make sense of random input; the random input probably comes from darkening of my peripheral vision when I’m fighting drowsiness. But nonetheless, I see fake people. They disappear when I turn to look at them directly.
I do everything I can to avoid driving when I am this tired, but I have work to get to, and a kid who needs to get to school, and other people are remarkably unsympathetic. I have been in an accident before, falling asleep behind the wheel, albeit, it was plain old falling asleep behind the wheel, it wasn’t braking for a phantasm.
I’m terrified of doing that—braking for a person who isn’t really there, and getting rear-ended by a person who is.
Anyway, the REM sleep—one of the problems that popped up in a sleep study I had done is that I tend to wake up when I go into REM sleep—as though entering REM itself startles me into wakefulness. This is why I have a medication that is supposed to reduce my startle reflex.
Another fact about REM sleep and sleep deprivation is that when you are deprived of REM sleep, you can enter it immediately upon falling asleep. It isn’t supposed to work that way– you go through other stages of sleep, and after a couple of hours, enter REM– but if you are deprived enough, you’ll go straight to REM. So, some mornings, after sleeping from about 8pm-1 or 2 am, getting up and doing some things—I do laundry, clean the living room, change the cat’s litter, clean the fish tanks, and walk the dog– I will go back to bed for an hour, maybe 90 minutes, and will have terrifying, beautiful, vivid dreams—dreams worthy of the major prophets—dreams that could keep me writing novels for years—cranial near-event horizons I manage to claw back from. Flavors jump out of my mouth and dance in technicolor, smells drip from my fingers. I fly until my wings ache, and converse with water. And I wake up rested. Rested the way I imagine a full night’s sleep would make me feel.
So cramming some really powerful dreaming into an hour seems to make up for a lot of things. It’s probably not great for me to get my sleep piecemeal like that, but I’m hoping it’s at least better than nothing.
Rapid cycling into REM sleep is a symptom of sleep deprivation, so it goes hand in hand with insomnia, but it’s also a symptom of narcolepsy, so if you cycle rapidly into REM sleep during a sleep study, you can get a narcolepsy diagnosis, which is exactly what you don’t want if you are an insomniac in the midst of very bad sleep deprivation.
In the midst of very bad sleep deprivation is when insomniacs tend to get sleep studies done, though.
When I went in for my first sleep study, I was told to bring all my medications. That didn’t seem quite right to me—didn’t they want to see me not sleeping? No; they wanted to see what my brainwaves looked like when I was sleeping, however I got there.
I don’t remember what I took in the way of PRNs to get to sleep during the study, but I took something, and still lay awake for a while, albeit, who wouldn’t with all the electrodes glued to their head? But I fell asleep. No white noise machine, no reading before bed, and with the knowledge I was being watched.
I’m not quite sure how many hours of sleep I got, but it was enough for them to get data. And I did not rapid-cycle into REM sleep.
Apparently, I did wake up once early in the morning, fall back asleep, and rapidly cycle into REM sleep, and that set off bells, in spite of the fact that they’d just watched me get an inadequate amount of sleep on heavy medication.
They made me finish off the morning with some kind of narcolepsy test that consisted of getting me to wake up fully, then lie back down, and see if I’d, first of all, fall back asleep, and second, if I’d rapidly cycle into REM sleep if I did. I never did fall back asleep, tired as I was, though, so I “passed” the narcolepsy test. I had told them it was ridiculous—I was there specifically for insomnia, pretty much the opposite of narcolepsy. But everybody gets the same test. I was checked for sleep apnea as well, which I don’t have, and didn’t have symptoms of—I’m not a snorer, for example. But as long as they have you there, having spent over an hour gluing all those electrodes in place, they’re checking for everything.