During the 16 hours of the day when we’re awake, we’re mindful of our actions, movements, and thoughts. What about the other 8 hours that we spend sleeping? A compilation of random thoughts, images, and memories appear to the sleeping mind. This perplexing nocturnal experience is known as dreaming. ‘The royal road to the unconscious’, as Freud had once proposed, is a universal human mental activity that has been a topic of scientific, philosophical, and religious dialogue throughout history. Despite extensive research, scientists still lack a clear understanding of why we dream. However, from evidence, technological advancement, and new research methodologies, researchers have constructed some interesting theories that may widen our understanding of the reasons that lie behind dreaming.
During the 16 hours of the day when we’re awake, we’re mindful of our actions, movements, and thoughts. What about the other 8 hours that we spend sleeping? A compilation of random thoughts, images, and memories appear to the sleeping mind. This perplexing nocturnal experience is known as dreaming. ‘The royal road to the unconscious’, as Freud had once proposed, is a universal human mental activity that has been a topic of scientific, philosophical, and religious dialogue throughout history. Despite extensive research, scientists still lack a clear understanding of why we dream. However, from evidence, technological advancement, and new research methodologies, researchers have constructed some interesting theories that may widen our understanding of the reasons that lie behind dreaming.
A dream can be described as a state of consciousness characterized by sensory, cognitive and emotional occurrences which are formulated through images, ideas, events and sensations.. During certain phases of sleep, particularly in the REM phase, which stands for Rapid Eye Movement, certain circuits in the brain become activated in the brain stem, creating an array of electrical impulses. The brain synthesizes and interprets this internal activity and attempts to create a meaning from these signals, which results in dreaming. As aforementioned, we are not entirely sure why we dream, however, there are many theories which may bring us closer to deciphering this puzzle. Varying theories have emerged over time, we dream to…
Fulfill our desires
As proposed by Sigmund Freud, in the 20th century, dreams represent unconscious desires, thoughts, wishes, and motivations. According to Freud’s view, what dreams include from images and random thoughts propose symbolic meanings, which relate to the fulfillment of our subconscious wishes. He also theorized that everything we recall once we’re awake from a dream is a symbolic representation of our unconscious primitive thought and repressed desires, such as fear, sexual instincts, and insecurities. In his famous book “The Interpretation of Dreams”, Freud said that dreams are ‘disguised fulfillments of repressed wishes’. Researchers claim that the appearance of these underlying thoughts suggests that there is a dream rebound effect, also known as dream rebound theory, in which unconscious content tends to be revealed in our dreams. The purpose of dreams under this theory is to bring about these deep desires to the conscious mind, in order for such repressed feelings to be confronted and reconciled by the dreamer. A research study funded by The University of East London presents an experiment that aims to investigate whether emotional valence of a suppressed thought affects dream rebound, and whether dream rebound subsequently influences subjective emotional response to the suppressed thought. 77 participants who were randomly assigned to pleasant or unpleasant thought suppression conditions, suppressed their target thought for five minutes prior to sleeping every evening. Each participant reported the extent to which they successfully suppressed their thoughts and reported their dreams every morning, for seven days. It was found that unpleasant thoughts were more prone to dream rebound than pleasant thoughts. Dream rebound and successful suppression were each found to have beneficial effects for subjective emotional response to both pleasant and unpleasant thoughts.
“The dream is the liberation of the spirit from the pressure of external nature”
Sigmund Freud
Rehearse
The vast majority of emotions experienced in people’s dreams are negative; most people label their dreams as “stressful”, “scary”, and “confusing”. As counterintuitive as it may seem, dreams involving negative emotions, such as fear and panic, actually prepare us to confront dangerous scenarios. This is called “the primitive instinct rehearsal theory”, which suggests that rehearsing these skills in our dreams allows us to practice our fight or flight instincts, giving us an increased potential for survival by building mental capability for handling such scenarios. The more you practice (dream), the more you are reprogramming your brain to face frightening and embarrassing situations if they happen for real. This theory works well to make sense of the often weird, daunting, and discomforting dreams that many of us experience, such as drowning and being incapable of breathing, showing up in public naked, or being chased by chucky. To sum it up, according to this theory, these dreams are intended to prepare us to cope with these experiences in the real world.
Remember
Oneirology mainly argues that sleeping benefits the retention of memory. Sleeping allows us to consolidate and process all of the information that we have collected during the previous day, and some experts suggest that dreaming has a dominant role in this processing experience. Initial theories have shown that certain memory processes can only happen when we are asleep as memories undergo a process of system consolidation. This consolidation originates from the reactivation of recently encoded memory, short-term memories, which are formed in the hippocampal gyrus and then transformed into permanent links in the cerebral cortex to form long-term memory. Newer findings revealed that this occurs during SWS (slow-wave sleep). Current Biology published a study in 2010 in which researchers asked 99 participants to play a virtual reality maze. The investigators tested the participant’s memories by asking them to remember objects in the maze. Then, half of the participants took a nap. The scientists tested all of the participant’s memories of the maze and realized that the people who had napped had better memory than those who stayed awake. Moreover, those who dreamed of the maze were up to ten times better than those who were awake between attempts and who napped but did not dream.
Forget
Contrary to the ‘Remember’ theory, our brains also help us forget certain things by condensing and filing away all the unnecessary information. We come by a multitude of data on a daily basis – too much to remember each one vividly. At the risk of being overloaded, our brain must go through an unlearning process, which results in our dreams. In 1983, an article written by Francis Crick and Graeme Mitchison talked about a neurobiological theory of dreaming called ‘Reverse Learning’. According to this theory, about 10,000 trillion neural connections are created in the neocortex in a semi-random way from our constant thinking and learning. Through dreaming, nonessential connections in the neocortex are eliminated. This happens because during REM sleep, the neocortex’s major connections to the external world are shut off. The brain stem sends random stimuli to the neocortex, causing some of the connections to weaken, this in turn eliminates some thoughts. Without this unlearning process, our brain would be overrun by useless connections and parasitic memories that might harm our mental health. The bizarre or nonsensical dreams may be a flash of memories as they are being erased.
“They do not deceive, they do not lie, they do not distort or disguise… They are invariably seeking to express something that the ego does not know and does not understand,”
Carl Jung wrote about dreams.
Heal
Sometimes we experience emotionally fraught and upsetting dreams, reflecting real emotions that we develop from stress, anxiety, and traumatic experiences. Dreams in this case work as a form of overnight therapy. During our REM-sleep, stress-triggering transmitters, like noradrenaline and norepinephrine, are vacant in the brain, leaving the brain in a relaxing and calm area. This state allows troubling events to be reactivated, which allows the dreamer to reprocess them to allow for psychological healing. Mathew Walker, a neuroscientist at the University of California Berkeley, conducted sleep research. Walker says that he got the idea for the study when he heard that a side effect of a blood pressure drug is known to reduce norepinephrine levels in the brain. He concluded that somewhere between the initial event and the later point of recollection, the amygdala- a brain region responsible for emotion and stress- activity was reduced, leaving levels of norepinephrine very low. Reprocessing upsetting experiences in this safe environment leaves us feeling better about our thoughts the following day. Studies that reference this notion have helped scientists to understand how PTSD (post-traumatic stress disorder) works in the brain. Indeed, many PTSD patients have difficulty in sleeping, and some researchers speculate that a lack of dreaming may contribute to their illness. The REM “therapy” is important for both PTSD patients who are coping with extremely stressful memories and for regular people coping with stressful situations in their daily lives.
As we have seen it’s still not clear why we dream, but as the world faces rapid progression in technology it may be possible to reveal the whole picture behind it one day. But what about recording our dreams? Would it be beneficial for us to be able to record them, and play them back? Scientists still haven’t made advancements in dream-recording techniques, but they’re marching towards the right path to reaching their goal. For example, in 2011, at Gallant Lab at The University of California, Berkeley researchers had participants watch movie trailers. The researchers reconstructed low-resolution videos of what the subjects were watching using only their brain activity. The videos were very low quality and undefined reproductions of the trailer. Still, this experiment uncovered novel approaches for other scientists looking to record dreams. In April 2017, a couple of scientists from The University of Wisconsin- Madison discovered that a decrease in low frequency activity in the “posterior cortical hot zone” of the brain serves as a signal for when dreams are occurring similarly to an illuminating red recording light. In addition to identifying cues from the brain that indicate a dreamstate, these researchers have also found that parts of the brain involved in perception during our waking hours behave the same way during sleep.
Yukiyasu Kamatani, who is a neuroscientist at Kyoto University, has conducted interdisciplinary research which combines neuroscience with computer science. He and his colleagues used artificial intelligence algorithms to explore the unconscious realm. Kamatani and his team say they have decoded the categorical contents of dreaming. They have developed a means of deciphering imagery from a walking person’s mind, by using the same means, they hope to develop the technique for those in slumber. “I think at least some visual aspects of dreaming can be captured in the form of a movie at low spatial and temporal resolution. It should be noted that a movie might be just a coarse approximation for a dream”, says Kamatani.
As interesting as all this is, dreams are fascinating things both for the individual and for scientists in general. As more efforts are spent on unveiling the secrets of dreaming, giving us a deeper understanding of the reasons that lie within, a lot of new questions arise, and the answers aren’t exactly satisfying. What we know is that the future holds new capabilities and features moved along for flow. Until that time comes, we’ll just have to keep on dreaming.