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What do dreams do? Dreams are a way for our brains to process stress and emotionally charged memories.
This is one of the most well studied, commonly held theories about dreaming—that our brains employ dreams to work through emotionally difficult and stressful experiences, to reduce their psychological load and make them less disruptive to daily functioning.
Clearly, most of us are coping with unusual levels of stress right now, and our brains are using dreams to process it. As unwelcome as nightmares and disturbing dreams feel, they may be a sign of the brain doing some essential, important work to ease the intensity and emotional charge of our currently heavy daily load of stress and worry. And our nightmares can also serve the purpose of alerting us to anxieties we haven’t yet become aware of, or given name to.
Research into trauma and its relationship to dreaming and sleep has shown that the more closely and directly people are affected by traumatic events, the more likely it is for their sleep to be disrupted and for nightmares to be intense. Nightmares are highly common among people with post-traumatic stress disorder. Nightmares associated with PTSD also are more likely to be direct replays of the trauma triggering event. In 2009, researchers looked at the impact of an earthquake in Italy, and found the most disturbing dreams and disrupted sleep occurred in people who were nearest the epicenter of the quake.
The people in the “epicenter” of the coronavirus pandemic include health care workers and other first responders, people who are sick or who are close to someone who is sick. There are also millions of people who have been laid off from jobs, and people who are facing economic crises that place them in an economic “epicenter.”
But it’s important to note: You don’t need to be at any of these “epicenters” of the crisis to experience trauma, sleeplessness, anxiety, and nightmares from the effects of the pandemic. Trauma and its fallout on sleep and dreams is in no way exclusive to first responders or the sick and their families. We’re living through unprecedented, frightening times, with a future outlook that is deeply uncertain. That’s a universal—and potentially traumatic—reality right now.
How does the brain process emotions during sleep and dreams?
We know something about these mechanisms, and it’s pretty interesting. During stages of sleep, areas of the brain enter a state of what’s known as “emotional disinhibition.”
This occurs particularly during REM sleep, which is when we do most of our vivid, complex, emotionally-laden dreaming. To achieve this state of emotional disinhibition, a region within the brain known as the dorsolateral prefrontal cortex shuts down. This part of the brain performs many complex executive functions involving memory, self-awareness, attention, and inhibition and control of emotional responses. The effect of this part of the brain shutting down creates an unselfconscious free flow of emotion within dreams. Basically, it’s “Party Time” for your brain, and it can now go outside the realm of reality (because you are in the unconscious) where the laws of physics simply do not apply.
Bottom line: Dreams are where your brain processes information.
An important exception is lucid dreams. During these dreams, part of the dorsolateral prefrontal cortex appears to become more active, not less, which scientists think contributes to the self-awareness and ability to control and direct activity within lucid dreams. I’ve written about lucid dreams—what they are, how they work, and how to encourage your brain to dream more lucidly.
Dreams are a "rehearsal" for real-life threats and challenges
This well-established, long-held theory of dreams provides another explanation for why so many people’s dreams are so heightened, intense, and disturbing right now.
So much of the study of dreams revolves around the question: Why do we do it? Amazing as it may sound, we don’t yet know for sure the purpose of dreams. Here’s a primer I wrote a few years ago on the basics of dreaming, including the most popular and well-researched theories about the purpose of dreams.
One of the most interesting and compelling hypotheses of dreaming is this one, known as the threat-simulation dream theory.
According to this theory, and the scientific evidence that supports it, dreams are a rehearsal space for the mind to “game out” threats and obstacles it anticipates facing in waking life, and practice how to best respond to these challenges. In this theory, dreams are a kind of virtual reality “training camp” simulation in the brain, with a focus on tackling the challenges the brain has identified as the most pressing and important to prepare for.
When you think about it in evolutionary terms, this theory makes a lot of sense. Imagine our ancient human ancestors living under constant and immediate threats–from animal predators, from human rivals, from forces of nature. Today’s predators and challenges are somewhat different, but the capacity for the brain to run simulations when faced with threats and danger remains intact.
Keep in mind, the body does not distinguish between the stress and agitation caused by thinking about losing one’s job or a loved one becoming sick, and the stress and agitation caused by being chased across an open field by a wild animal. When we’re constantly anxious and worried, our bodies take up residence in “fight or flight” mode, and dreams may take up the work of helping us rehearse our way out of our problems.
Bottom line: Dreams are a good place to “practice” or “train” for real-life situations.
We draw heavily on daily life for dream material
Pieces of our daily experiences show up in dreams all the time, a well-studied phenomenon known as “dream incorporation.” Dream research has shown that some memories from daily life show up in dreams immediately, that same night. This immediate transfer of memories into dreams is known as “day residue.” Other memories from waking experience are subject to what scientists refer to as a “dream lag.” That’s a delay, typically of about 7 days, between a memory being created in the waking day and it showing up in a dream.
Stay Safe and Have Sweet Dreams,
Michael J. Breus, PhD, DABSM
