Why Do We Dream?

Why do we dream? This is one of life's great unanswered questions. Given that we spend around six years of our lives in a dream state, it's no wonder people want to understand why we do it. Sure, there are theories, and I'll get to them, but there's no clear consensus on why we do it. No one really knows for sure. Or do they?

Dreams are strange, to say the least, and for many of us, they hold great significance. So much that we like to share them with others at length, if we can even remember them, and try to interpret their secret and hidden meanings. So, do they actually hold any real meaning? Well, I have some ideas.

Before we get to some of the bigger questions, let's just look at what goes on inside the brain as our nighttime adventures take their course. While sleeping, we go through different cycles of the five stages of sleep. These are divided into REM sleep and non-REM sleep. REM simply means the rapid eye movement; it explains itself, right? The first four stages are non-REM sleep. These are restorative and, for the most part, dreamless.

As we move through these initial stages, our brain activity slows. But about 90 minutes after we finally fall asleep, we hit stage five: REM sleep. This is when the dreaming really gets going. When we're in this stage, the body is, for all intents and purposes, paralyzed. Your heart rate goes up, your blood pressure rises, and brain activity returns to near waking levels.

The paralysis in REM sleep is caused by the release of glycine, an amino acid from the brain stem onto your brain's motor neurons. It's suggested that this paralysis is nature's way of preventing us from acting on our dreams, and that's probably for the best. The limbic system is a pretty primitive part of the brain that deals with emotions, and it's very active during REM sleep.

It's made up of the amygdala, which is mostly associated with fear; the hippocampus, which is heavily involved in the formation of long-term memory; and the cingulate gyrus, which is involved in our physical reactions to situations. Break down the roles of these bizarre brain structures, and we can start to paint a picture of why our dreams often take the bizarre and scary forms they do.

Couple this with the fact that the prefrontal cortex, the part of the brain that deals with logic and self-control, isn't really active during REM sleep, and things might just start to make sense. But understanding it isn't enough to prevent these nightmares from happening. It can also happen while you're awake.

Sleep paralysis is a terrifying concept. Like I just mentioned, when you fall asleep, your brain doesn't completely shut off. In order to prevent you from acting out your dreams while you sleep, the brain releases chemicals that leave you paralyzed. This paralysis is supposed to be lifted as soon as you wake up, but sometimes it doesn't, and that's where you get sleep paralysis. You wake up, you're aware of your consciousness, but you can't move. It feels as if there's a massive weight on your body preventing you from actually waking up.

Sleep paralysis is often most caused by disrupted REM sleep, so some people may believe they're still dreaming when they're, in fact, awake because of this. Some of your nightmares could leak into the real world while undergoing sleep paralysis. You'll often see things standing in the corners of your room or on the ceiling, or even closer. Luckily, this usually goes away pretty quickly.

So, is it just biology? Is that really the answer? Is there no secret window into our psyche? Everyone at one time or another has wondered what their dreams mean. Some believe that dreams have no meaning and serve no function; others believe that they're one of the most important things that human biology has allowed to happen.

There's, in fact, many theories of why we dream and what purpose it serves. I can't really go any further without mentioning Freud, whose theories of dreams are probably the most well-known around the world. It focuses on the content of the dreams themselves as an explanation of the function of dreaming.

German psychiatrist Sigmund Freud theorized that dreams represented a window into the unconscious mind, a reservoir of feelings, thoughts, urges, and memories that are beyond our conscious awareness—the bulk of the iceberg submerged deep underwater. Most of the contents of the unconscious mind are supposedly unacceptable or unpleasant, representing feelings of pain, anxiety, or conflict. When we're sleeping, the forces that keep these feelings in check are weakened, allowing us to live out our desires and even fears through our dreams.

Freud strongly believed that by exploring dreams, people could increase self-awareness and insight into their unconscious self, which would then help them deal with problems in their day-to-day lives. He also argued that the true meaning of our dreams is hidden within their actual content, and that interpretation is needed to understand how they relate to our unconscious fears or desires.

Many of you watching might even agree with this, despite the fact that there is absolutely zero evidence to back this account. It is pretty much unfalsifiable, even though more modern explanations now exist that are better informed due to a deeper understanding of how the brain works.

20th century Swiss psychiatrist Carl Jung also believed that dreams allow us to tap into the unconscious but argued that it was a collective unconscious that we were able to access through our dreams. According to Jung, this is a theoretical repository of information shared by everyone, in which certain symbols in dreams have meanings that are similar for all people regardless of culture or location. This could explain why so many of us share variations on common themes in our dreams, like falling, being chased, or our teeth falling out. Any of these sound familiar?

Dream interpretation is the process of assigning meaning to dreams. Even today, the practice plays an important role in various forms of psychotherapy, which is surprising given that there is only a little evidence so far that shows understanding of interpreting dreams has a positive impact on mental health. This could be because evidence also shows that people tend not to attribute equal importance to all dreams. Motivated reasoning comes into play; people are more likely to view dreams that confirm their waking beliefs and desires as meaningful compared to dreams that contradict them.

But just for fun, let's take a look at some interpretations of the most common dream themes. We've all had the falling dream, right? Well, this could be a warning from your subconscious and is common in people who are having a major life problem with work or relationships. It could be an indication of insecurities, instability, or worries. You might be feeling overwhelmed and out of control in some situation in your waking life. This type of dream could also reflect a sense of failure or inferiority in some circumstance or situation.

It's typically suggested that showing up to work or school naked represents vulnerability and anxiety. Clearly, research has demonstrated that this dream is common in people who have accepted a promotion, gone off to a new job, or who are coming into public view. Others argue that it means you may be hiding something and are afraid that others can see right through you.

And despite the nightmarish feel of dreaming that someone or something is chasing you, it can be considered a positive message—that would prompt from the unconscious to encourage the dreamer to face a problem they've been avoiding. It's suggested that who or what is chasing you and how far away they are is important.

These common themes barely touch the surface of the complexity and endless variety and variations of dreams we know. Dream interpretation can be entertaining, but there are definitely more contemporary theories about the purpose of dreaming that are probably important to consider. A better understanding of brain function and activity has allowed for the development of neurobiological theories in more recent years, one of which is the activation synthesis theory.

Not quite as intriguing as the psychoanalytic approach, in fact, it's pretty boring. This theory simply rejects the idea that dreams mean anything at all, which is disappointing. They can be merely electrical brain impulses that pull random thoughts and imagery from our memories. Activation synthesis suggests that humans could create dream stories after they wake up in a natural attempt to make sense of the absurd.

I kind of get it. There are some holes in this theory too, though. The main one being that there is vast documentation of the realistic aspects of human dreaming and evidence that dreams do reflect real-life events that are important or prominent for the dreamer.

For example, a study in 2006 asked women who were going through a divorce to report the degree to which their former spouses were on their minds over a five-month period. These same women were awakened during REM sleep on three nights and asked to provide a detailed account of their dream content. A positive correlation was found between the degree to which women thought about their former spouses during waking hours and the number of times their former spouses appeared as a dream character.

In another study, researchers demonstrated that dreaming can help solve complex mental tasks. Participants were much better—ten times better, in fact—at getting through a complex 3D maze if they had napped and dreamed of the maze before their second attempt. This strongly suggests that certain memory processes happen exclusively during sleep and that our dreams are not only a signal that these processes are taking place but seem to be crucial to better performance.

So, unconstrained by reality and the rules of conventional logic, the dreams your mind can create have the potential to lay out limitless scenarios to work through problems and produce solutions that you may not have even considered while awake. So it turns out that dreams can be influenced by pre-sleep emotions and can be really helpful for problem-solving. So that's another theory put to bed.

The continual activation theory proposes that the conscious and unconscious mind must remain continually active in order to maintain proper brain function. In this context, dreams function to consolidate working memories into long-term memories, and dreaming is simply an incidental result of the brain's need for continual activation. This means that if the brain's activity falls below a certain level, such as during sleep, it is stimulated to maintain activity through dreams.

The expectation fulfillment theory explains dreaming as a way to release emotional arousal that hasn't been expressed during the day. This frees up space in the brain to deal with the emotional arousal the next day. It allows instinctive urges to stay intact. In effect, the action we wanted to take is completed in a metaphorical form, and this prevents a false memory from being created because we perceive the action as a dream instead.

So, dreams are metaphors for unfulfilled arousals and expectations. But because sleep is not involved, the same stimulation of waking life, dreams draw memory instead of motor or sensory activity. It is this process that generates the unusual imagery, narratives, and thought patterns we experience in some dreams.

This explanation has received validation anecdotally through people's personal experiences. The same old story; it is essentially unfalsifiable. Interpretation of dream events is subjective, so we aren't able to put this theory through rigorous scientific testing. I could go on with the theories for days, but you get the point. No one really knows. It's very difficult to disprove most theories.

Maybe some of the more fascinating dream phenomena can shed light on the function of dreaming. The term lucid dreaming was coined by Van Eden way back in 1913, although people were writing about this kind of experience as far back as the 1800s. It describes a state in which the dreamer is aware they're asleep and sometimes has the ability to control events and actions, most commonly occurring during late-stage REM sleep, and essentially allowing your conscious mind to control something your unconscious mind normally controls.

Lucid dreamers report being able to fly, taste, smell, and touch pretty much anything they want. It's more common than you think, with about 55% of people having experienced the state at one time or another. For starters, participants were asked to perform specific ocular movements if they became lucid while dreaming. By ocular movements, I mean moving your eyes—that's literally it.

This is possible, actually, and it's kind of ingenious because eye muscles are free to move during REM sleep. By determining exactly when the sleeper was lucid dreaming, researchers were able to take recordings of brain activity during the state. The evidence showed some interesting and specific brain activity that represents a mixture of both waking and normal REM sleep.

It also seems that the brain undergoes a specific altered state of physiology during lucid dreaming that constitutes a hybrid state of consciousness. Studies have shown that the prefrontal cortex, as well as the frontal, parietal, and temporal zones, become activated. These areas of the brain are responsible for higher-order cognitive functioning, including working memory, cognitive flexibility, planning, inhibition, abstract reasoning—the list goes on.

So, besides being quite entertaining, why do it? Can we learn anything from it? Some advocate many potential benefits, including boosting creativity and confidence, reducing stress, and as a possible therapeutic technique to treat nightmares, PTSD, and other mental health disorders. Others view the practice as more spiritual and approach it the way they would meditation, with the intention of increasing the person's sense of the vastness of reality and opening up new realms of discovery.

It's even been suggested that some advanced meditation practitioners are able to become conscious of borders beyond the dream state—the deep formlessness of Delta sleep. This is questionable at best and in need of much further study. Given our current relatively limited understanding of the brain, it's hard right now to understand how it could be possible to be conscious of deep sleep because the brain is in a far more synchronized and deeply unconscious state compared to almost any other state of consciousness. But hey, who knows?

Despite the evidence, lucid dreaming remains a controversial topic. Alternative explanations have been suggested for the phenomenon. It may be that lucid dreamers are in a daydream-like state of semi-wakefulness, or they are dreaming normally but have a memory of the dream and believe that they were conscious and directing the dream when they were not. It could be a sleep state dissociation in which the person is both awake and asleep in the dream state at the same time.

I suppose it's even possible that people who aren't reporting true experiences, but I personally don't think this is what's going on. If lucid dreaming is as real as they suggest, I'm left wondering if dreaming serves any of the purposes I've already talked about, such as accessing the unconscious, acting out instinctive urges, solving problems, or whether they are simply electrical impulses keeping the brain from shutting down.

How does being a conscious witness affect how they play out? Does it hinder or help? Is it a state of heightened reflective consciousness that humans are meant to access so that we can enlighten ourselves about our life, our world, and our purpose? Or does lucid dreaming stand alone in its function to serve an entirely different purpose?

Have you ever dreamt of an event only to find out that it happens in your waking life? It's a weird occurrence. Precognitive dreams are dreams that appear to predict the future through a sixth sense, and there are some pretty famous examples of this happening. When the Titanic sank in 1912, hundreds of people came forward with reports of psychic dreams about its sinking. It was even possible to validate at least 19 of them, including a date-stamped letter. Several people apparently canceled tickets and decided to not travel based on their dreams.

Are all 19 of these people psychic? Well, no. In fact, in this case, it's likely to be simple math and the power of probability. Think about it: there are seven and a half billion people on this planet, each having an average of five dreams per night, whether you remember them or not. In turn, those dreams support multiple common dream themes, including events like sinking ships and airplane crashes.

When all of this is considered, in reality, it's highly likely that many thousands of people will dream about a sinking ship on any given night—probably tonight! Now, add a bit of unconscious insight and media suggestion for good measure. The Titanic was the world's largest ship on its maiden voyage and was in the headlines before it even undocked. The media had called it unsinkable. The power of suggestion is immense, and it's no surprise that all this news attention, and maybe even some nerves about taking such a huge trip, infiltrated more than just a few dreams.

So, the next time you dream about an event that has nothing to do with you and it comes true, it's probably just a coincidence. Probably. But what about dreaming of your own death? This is a deeply personal experience and probably not subject to extensive media attention. It's exactly what happened to Abraham Lincoln.

Two weeks before he was shot dead in 1865, Abraham Lincoln had a dream about a funeral at the White House. When he asked someone who was in the casket, they replied, "The President." He was killed by an assassin. Clearly, he didn't listen because, at the time he was assassinated, he had given his bodyguard the night off.

If the premonition dream is about something close and personal to you, some might argue that your subconscious mind is accessing a piece of information that you weren't consciously aware of in your waking state. You just missed it. The brain has so much to process every second you're alive. It only makes sense that some information is lost, so it's less psychic power and more inner feelings or intuition that you're experiencing through your dream.

And this takes us deeply full circle back to the question of why we dream. If you don't believe in psychic abilities that manifest in dreams, then precognitive dreams are essentially a window into our unconscious. Of course, as always, some disagree with these explanations of precognitive dreams and suggest that what matches across such a reliable and frequent basis can't be entirely down to coincidence.

Some of these people turn to a mix of philosophy and physics to understand how precognitive dreams might happen. To truly understand these theories, it is necessary to assume that the future consists of many possibilities and which one becomes reality is determined by the choices we make. The butterfly effect shows up yet again.

Ultimately, common sense would tell us that dreams likely serve many purposes as opposed to just a single one, and how we choose to understand our dreams and why they happen is largely a product of time and culture. The function of dreams may have even changed as humans have and continue to change across time itself. What once acted as a rehearsal system for evading predators is now serving to help us navigate the social and technological complexities of modern life.

And stress? Dreaming is vital. The link between dreaming and REM sleep is undeniable, as are the benefits of REM sleep for our health and well-being. So don't stifle them; they're only trying to help you. Sweet dreams!

Dreaming is something we all do, and some of the world's greatest discoveries have come from ideas during the dream state. Learning how the brain works is an ongoing journey, but we're already working on making our technology act more like our brains—for example, neural networks. But those can be hard to understand.

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