So, getting back to your regular dreamy programming will often require first getting back to your regular sleep schedule, as the two go hand-in-hand.
And with that additional time in REM, the brain can spin more elaborate dreams to boot. “Each REM period through the night is longer than the one before, so anyone sleeping longer than eight hours as they catch up will also have extra-long REM periods not seen on other nights,” says Dr. The longer you sleep on your catch-up days after sleep loss, the more potent that effect can be. In other words, you’re having dreams in a haphazard or jarring way, without being able to really digest the material. “In regular REM sleep, the brain acts like a second gut, chewing and digesting waking-life experiences and consolidating those memories as dreams,” he says.īut in REM rebound? It’s almost like you’re fast-forwarding that process, with dream content showing up in “bursts or quick releases, in a way that’s not comfortable or rhythmic,” he says. Usually, these dreams arising during REM rebound aren’t exactly great or high-quality, according to Dr. “This means that both the eye movements in this stage and the brainstem electrical activity causing them will increase, all of which is correlated with more intense dreams.” “On nights when we’re catching up on sleep, we have greater ‘REM density,’” says Dr. Why sleep deprivation and the resulting 'REM rebound' can trigger more vivid dreamsĪs the body begins to make up for lost REM sleep by moving you more quickly into REM during the nights following sleep loss, you’ll also experience this dreaming stage more intensely. Barrett, whereas those getting anywhere from 12 to 24 hours of sleep deprivation are far more likely to experience REM rebound and the more intense dreams that come with it. Remember how the body first prioritizes catching up on non-REM sleep after a bit of sleep loss? That’s likely why sleepers deprived of only a couple hours of sleep usually experience only non-REM rebound, says Dr. But, in a non-lab setting, she caveats, REM rebound (and its vivid dreams) may require greater levels of deprivation to show up. Scientists have identified this particular rebound phenomenon by selectively depriving (consenting) folks of REM sleep in a sleep lab (that is, waking them up every time their brain waves showed them dipping into REM sleep), and then monitoring their sleep afterward, says dream scientist Deirdre Barrett, PhD, author of The Committee of Sleep and Pandemic Dreams. The result? REM becomes “increasingly pressurized, and starts to push back against that deficit, leading eventually to REM rebound, which is when REM sleep shows up earlier in the night and to a greater depth and intensity, even displacing deep sleep in the process,” Dr. (The same is true if you’re frequently waking up during the middle of the night, which often happens right at the onset of REM, essentially cutting it off and bringing you back to the beginning of your sleep cycle whenever you fall back asleep, Dr. Naiman, leading you to experience shorter and shorter periods of REM sleep. “REM rebound is when REM sleep shows up earlier in the night and to a greater depth and intensity, even displacing deep sleep in the process.” -Rubin Naiman, PhD, psychologist and dream scientistīy contrast, once you start to experience some sleep deprivation-say, cutting back from your usual seven hours of sleep to five hours per night for a few nights in a row-the body starts to prioritize deep sleep (the last stage of non-REM) over REM, says Dr. “In this case, you’re rhythmically moving through all the stages of non-REM sleep, being dipped into more profound levels of serenity and deep sleep before the dreaming process really begins,” he says. On a night of average sleep, in which you’re not making up for any sleep deprivation, you’d typically get five minutes of REM at the end of the first 90-minute sleep cycle, 10 minutes at the end of the second, and so on, until you’re getting somewhere around 45 minutes at the very end of the night, which is when you’d experience most dreaming, says psychologist and dream scientist Rubin Naiman, PhD. To grasp how, exactly, REM rebound occurs and why it can deliver such vivid dreams, it’s helpful to know how REM typically shows up (when it's not rebounding).