Sleep is unbelievably important for humans. As far as biological needs go, sleep is right up there with water and oxygen. It plays an important role in boosting our immune system, regulating metabolism, controlling appetite and so much more.
Unfortunately, good sleep is elusive to many Americans. According to the National Sleep Foundation, 45% of Americans report that “poor or insufficient sleep” affected their daily activities at least once in the last week. And according to a Consumer Reports survey of over 4,000 U.S. adults, 68% reported having trouble sleeping at least once a week.
Many people credit insomnia as the reason they turned to medical marijuana. Cannabis has been shown to effectively decrease sleep latency, or the time it takes for a person to fall asleep, in male chronic cannabis consumers.
And while cannabis can help you say hello to quality sleep, it could cause you to say goodbye to something else: dreams.
In one eight-hour night of sleep, we go through the sleep cycle about three times on average. There are five stages total: Stages 1, 2, 3, 4 and REM (Rapid Eye Movement) sleep; each stage has specific brainwaves associated with it.
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A study from 1972 used young adult male volunteers and dosed one group with tetrahydrocannabinol (THC) and another with a synthetic compound similar to THC, called synhexl. Each subject then had their brainwaves measured with an electroencephalogram (EEG) while they slept. Researchers found that varying levels of THC as well as synhexl increased Stage 4 sleep (deep sleep), but decreased REM sleep.
We know that dreaming happens during REM sleep. If THC decreases the amount of REM sleep a person gets, then it also decreases the amount of time a person has to dream.
Of course, these findings should be looked at with a critical eye. The study is from 1972, and there hasn’t been, so far as we can find, a study done like it since. Only a small handful of subjects—all of whom were young and male—were studied, so the sample isn’t representative of the entire population.
Let’s imagine that the results from the study above and the anecdotal evidence is correct, and cannabis consumers do experience a decrease in dreams. Is that a bad thing? How important is dreaming on a biological and emotional level?
The jury is still out on just how important dreams really are to humans. Researchers haven’t quite nailed down the exact function of dreams or determined their exact biological value. But there’s some interesting scientific literature on the topic.
Historically, most researchers have agreed that dreaming plays a role in processing emotional memories, balancing mood and learning. But David Maurice, Ph.D. and professor of ocular physiology at Columbia-Presbyterian Medical Center, believes REM sleep plays a different role: providing much needed oxygen straight to the cornea of the eye.
If dreams really do help process emotional memories, especially traumatic ones, dreaming could be an essential part of grief therapy and conquering post-traumatic stress disorder (PTSD). On the other hand, those experiencing PTSD with intense night terrors could be grateful for a break from the dreams.
One clear way that decreased REM sleep and increased Stage 4 sleep can adversely affect humans has nothing to do with dreams at all. Stage 4 sleep, while the deepest and most restorative stage in the sleep cycle, is very hard to wake up from. Forget waking up on the wrong side of the bed: If you wake up during the wrong stage of the sleep cycle, you’ll end up irritable and mentally foggy. If marijuana increases Stage 4 sleep like the 1972 study suggests, then that could explain why many cannabis consumers feel groggy when they wake up.
But don’t worry too much. Just because you consume cannabis now doesn’t mean you have to say goodbye to dreaming and REM sleep forever. If you abstain from marijuana, it’s likely you’ll eventually begin to dream normally again. In fact, you’ll probably experience a period of intense dreaming right after you quit consuming. This is known as REM rebound, which is known to occur after a person has been deprived of REM sleep.
So, if you’ve been using cannabis as a sleep aid and don’t think you’ve been dreaming as usual, there’s scientific research that says this can happen. If you miss your dreams, abstain from cannabis for a while and slide back into REM sleep.
Photo credit: Alexandra Gorn