5: Dreams
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Introduction
In the early moments of trying to fall asleep, we may experience a stunning hallucination that startles us back to reality, leaving us to wonder, “What was that?!” It is disorienting because we feel we were not yet sleeping. These hypnagogic hallucinations occur around sleep onset (Figure 5.1). They are a type of dream—if you define dreaming as something going through your mind while you are asleep—but some people refer to hypnagogic hallucinations as “sleep thinking.” We dream in all stages of sleep, NREM and REM, but during REM sleep, our dreams become more intense in their content and often bizarre in nature. Conversely, if awakened from NREM dreams, many report that it feels as though they were simply thinking about something rather boring. We know dreams occur throughout the night, but in this chapter, dreaming refers, unless stated otherwise, to the dreaming state associated with REM sleep. Let’s begin with a discussion of the importance of dreams to our mental well-being, because in the words of Nobel laureate Elias Canetti, “All things one has forgotten scream for help in dreams.”1
Emotional Healing
Dreams help us cope with, and better understand, our emotions. During the day, emotional events happen, but we rarely pause for reflection because we are pressed to continue with the business of the moment. When we are dreaming, it is an opportunity to take the emotions of the day and relate them to memories—even those from long ago—to see if we can make sense of the situation and be better prepared for the next time something similar occurs.
Imagine an emotional event during the day, such as a group activity in class in which you felt socially uneasy, like you did not fit in (Figure 5.2). Maybe you said something that was poorly received or were given a disapproving look by one of your classmates, but you had to continue with the work at hand. You may or may not have forgotten about it by the time you went to bed. Either way, that night, your dream might have an emotional theme of social rejection, but in a scene involving people you haven’t seen in years rather than your current classmates. Through dreams, your brain can create a mash-up of current and previous experiences to optimize your future behavior—the perfect harm-free dress rehearsal.
While our dreams are synthesizing such relationships between recent emotions and distant memories, the brain experiences its lowest levels of stress hormones over the course of twenty-four hours. One of these hormones, norepinephrine (also called noradrenaline), is present in the brain at various levels throughout the day and night—except during REM sleep. During our vivid emotional dreams, we can replay events without the stress response triggered by norepinephrine. Matthew Walker, a sleep scientist at the University of California, Berkeley, has led brain imaging research in this area to show how the brain takes advantage of this zero-norepinephrine condition to relate clear recollections of crucial events to previous memories without engaging the flight-or-fight brain circuits that would distract us from calm introspection. The result is that we are able to shed the emotionally painful layer of the memory and still retain details of the situation to help us be better prepared to face another day . . . or that judgy classmate!
Dreaming about emotional events brings us to a place where we are more comfortable with the situation. Psychologist Rosalind Cartwright, also a world-renowned sleep specialist and expert on dreaming, has published extensive research showing the benefit of dreaming for emotional recovery. Dreams mentally evolve us to a point where our daily activities, as well as our sleep, are less disturbed by feelings associated with challenging life events. She says a part of the purpose of dreaming is so that “negative mood [can be] down-regulated overnight.”2 Although, she is quick to clarify that recovery from difficult life events will take many nights, maybe months, of dreaming about them. Cartwright has done brilliant research and clinical work with patients experiencing despair at the time of an upsetting life event, such as a breakup with a partner (Figure 5.3). She found people who dreamt of the event, especially around the time of its occurrence, experience a significant amelioration of depression compared to those who did not dream of the event (even if they did still dream of other things).
This progression to recovery has a more complicated path for individuals faced with trauma and nightmares. If someone experiences a frightening or dangerous event, and feelings of being scared or stressed remain strong long after the danger has passed, they may have posttraumatic stress disorder (PTSD; Figure 5.4). People with PTSD have increased levels of norepinephrine in their brains during REM sleep. This is the opposite of the norepinephrine-free condition responsible for emotional healing during REM dreams, which is experienced by those without PTSD. For folks suffering from PTSD, the presence of norepinephrine during REM sleep disrupts the ability for dreams to reduce the emotional intensity associated with disturbing events. But because the mind still wants to work out the problem while dreaming, it will repeatedly attempt to do so with a dream, sometimes every night, resulting in recurring nightmares—one of the most common symptoms of PTSD.
Imagery rehearsal therapy (IRT) has been used successfully to help people with PTSD work with a therapist to transform nightmares into less disturbing dreams. The concept is to create a more comfortable version of the nightmare and retain enough nightmare details so the mind will slip into this new version. For example, if a person has a nightmare of being attacked by a shark, the new version will still have water splashing, a fin in the water, and the feeling of a strong bump against the body of an animal. However, in this new version, the splashing is from a dolphin playing nearby, not a shark thrashing; the fin is a dolphin fin, not a shark fin; and the bump to the body is gentle, from the friendly dolphin (Figure 5.5). People write out the new version of the dream, create an art piece depicting it, and tell the new dream as a story to another person. They meditate on the new dream before sleep to train the mind to shift over to this new set of details. Harvard psychologist Deirdre Barrett has written extensively about the benefit of working with dreams as a part of the recovery process for PTSD. She explains that dreams provide a “barometer” of a person’s mental state, delivering insight into a patient’s progress.3
Memory and Learning
Through dreams, our brains create connections between recent experiences and long-term memories. This equips us with new perspectives, allowing us to better respond to similar situations in the future. Our sense of self or identity also changes through dreams as we see our role in a recent situation through the lens of a memory from our distant past. Procedural memories—those for things like playing a song on the guitar or making your favorite cookies—are also processed and stored through dreaming. When we are learning a new procedure, let’s say a dance routine, we will notice the first time we try it after a night of dreaming, we will do much better than on the previous day. NREM and REM dreams both play a role in memory formation, but there is a difference. NREM dreams serve more to strengthen memories, and REM dreams restructure them, marrying fresh experiences to earlier ones.
Taking a deep look at how dream content has an impact on learning and memory, sleep science experts Erin Wamsley and Robert Stickgold studied navigation in a virtual maze (Figures 5.6a and 5.6b). Human participants trained on the virtual maze and then were allowed to sleep overnight. In prior animal studies on the subject, researchers had already shown that the animals’ brain firing patterns during sleep closely matched the patterns seen when they were learning a maze, but how could we know what the animals were dreaming about? Previous studies on animals and humans also provided evidence of improved performance being associated with sleeping after attempting a task. The novelty of Wamsley and Stickgold’s research was in asking participants about their dreams’ content during the night and establishing the clear relationship between maze-themed content in dreams and success in navigating the maze the next morning. They also found that the participants who did not perform well during practice sessions with the maze were more likely to see the maze in their dreams that night.4 If something is challenging for us, our brain knows we will be more likely to overcome the challenge if we dream about it. This fits well with Antti Revonsuo’s “threat simulation theory,” which posits that dreams help us develop better skills to behave successfully in the midst of difficult situations. He states that through dreams, we are able to rehearse threatening scenarios, with the result being improved outcomes in our next waking encounter with similar challenges.5
Knowing sleep has such a powerful influence on storing memories, University of California, Los Angeles, neuroscientist Gina Poe proposed a solution to help people with PTSD. The background for her theory is work from an assortment of scientists studying the relationship between sleep/dreams and memory. When trying to learn something, one way to increase memory capacity and accuracy is to sleep, and thus dream, shortly after exposure to the content. It turns out the timing of the sleep matters for optimal memory creation: the sooner, the better. This knowledge about timing is used to schedule sleep for someone who has experienced a traumatic event. Poe suggests it is beneficial to hold off—for around eight hours after the event—before sleeping.7 Delaying sleep onset diminishes the brain’s ability to store traumatic event details, so the person is less likely to create vivid and lasting memories that would haunt them.
With so much focus on dreams helping us create memories, we could overlook a theory from the 1980s stating one of the functions of dreaming is to “unlearn” information. Scientists Francis Crick and Graeme Mitchison present a model of dreams as a mechanism for sorting through information in order to discard unnecessary memories from the day. Consider when you are ready to leave campus: it is important you remember where you parked your car or locked up your bike. The next day, it is best if the parking information is not crowding up your memory space, but you still need to remember how to get to class; dreams, in this theory, are a way that parking information is culled while the route to class is maintained.
Problem Solving and Creativity
Stories of creative inspiration arriving through dreams are pervasive: Dmitri Mendeleev’s periodic table of elements, Mary Shelley’s idea for Frankenstein , Elias Howe’s design of the needle for the sewing machine, Friedrich Kekulé’s vision of benzene ring structure, Keith Richards’ guitar riff in Satisfaction , and more all are said to have come from dreams (Figure 5.7). Rather than take space here to provide the details of these worn-out stories, you may Google the topics—and when you do, you will find Google itself was born in a dream!
There is one story worth telling here. It is about an inspiring role model, Sarah Breedlove Walker (a.k.a. Madam C. J. Walker), who was a civil rights activist and philanthropist up through the early 1900s (Figure 5.8). The wealth she built to provide the financial resources to support herself and her philanthropy came in small part from a hair-loss remedy recipe that came to her in a dream. I say “small part” because most of her success is likely due to her fortitude. She started life as the daughter of freed slaves, living in financial poverty in Louisiana, and spent years working as a single mother, since her parents and husband died by the time she was twenty. Then after a hard day of work as a washerwoman, she had a dream where a recipe came to her, including ingredients she ultimately had shipped from Africa, for a product to help her restore her hair, which had fallen out. She ultimately became a successful businessperson and multimillionaire, dedicating herself to helping others. W. E. B. Du Bois said of Walker, “It is given to few persons to transform a people in a generation. Yet this was done by the late Madam C. J. Walker.”8
With scores of stories about dreams providing creative solutions, it is no surprise there is a bounty of research that shows sleeping and dreaming on a problem makes us more likely to gain insight into a solution. Psychologist Ullrich Wagner and his colleagues scheduled cognitive testing sessions so that one group of participants would sleep in between their first and second testing sessions, while the other would not. The test consisted of tiresome math problems. Rules were provided for generating the solutions, but it was still a tedious and prolonged experience. But there was a secret shortcut that could be used if the participant had an epiphany about an abstract rule. Such epiphanies, in which the solution to a seemingly unsolvable problem suddenly becomes clear, happen more often if we dream about our problems. Wagner’s team found that the people who slept between their first and second attempts had significantly more revelations that led them to the secret shortcut than those without the opportunity to sleep.9
But what if the participants’ epiphanies about the secret shortcut were due simply to the fact that they’d slept and had nothing to do with the brain restructuring memories of the test problems during their dreams? To factor this in, they needed to do additional data collection on participants who took the test only once. They divided participants who had not yet seen the test into two groups, those who slept before the test and those who did not. There was no difference between the two groups in terms of discovery of the hidden rule: the sleepers and nonsleepers had the same rate of epiphanies upon taking the test for the first time. In other words, a participant had to have seen the test problems before sleep (as in the protocol with people taking the test twice) in order for the rate of epiphanies to increase (as they did when those participants saw the problems again). Notice how the researchers included this essential part of the scientific method: seek to disprove your hypothesis and look for alternate explanations, even if it seems you have proven the hypothesis you were seeking to prove.
Emotional Intelligence
One of the pillars of healthy interpersonal relationships is emotional intelligence, which includes the capacity to understand and control one’s own emotions and to recognize and interpret the emotions of others (Figure 5.9). One aspect of this is being able to distinguish different facial expressions, such as for fear, anger, or joy. Without the benefit of time in our dream state, this ability drastically deteriorates to the point where not only do we lose the ability to tell the difference between a friendly or angry expression on someone’s face but also our tendency is to assume the more threatening option. This was discovered in Matthew Walker’s University of California, Berkeley, lab. Regarding how misinterpreting neutral facial expressions as threatening could cause harm, Andrea Goldstein, lead author on the study, urges, “Consider the implications for students pulling all-nighters, emergency-room medical staff, military fighters in war zones and police officers on graveyard shifts.” One of the fascinating aspects of the study was that they studied the participants in an MRI scanner, so in addition to having the evidence reported by the subjects themselves, the scientists could also see how well (or poorly in the case of less REM sleep) their brain structures were doing in terms of distinguishing between the different expressions.
How and Where Dreams Are Created
In the 1970s, Harvard medical doctors J. Allan Hobson and Robert McCarley postulated a neurobiological model of dreams. They described REM-associated bursts of electrical activity in cats as originating in the pons (a part of the brainstem), traveling through the thalamus, and arriving at the cerebral cortex (Figure 5.10). Along with this neuronal activity came twitches in whiskers and muscles, as well as jerky eye movements not typical of a cat tracking something visually, which therefore seemed random. The brainstem’s electrical activity patterns were not similar to those seen in animals processing real sensory information either; however, the cortex, influenced by this chaotic activation, was still trying to make sense of the activity and synthesizing the brainstem activity into a dream. This is the premise of Hobson and McCarley’s activation-synthesis model of dream creation. For some people, the activation-synthesis model makes a case for dreams being meaningless, since they are based on seemingly random activity. However, if we consider that the dreamer interprets dream content based on its relationship with their waking experiences, interpretations of dreams generated according to this model still provide an opportunity for personal insight.
Debate about the activation-synthesis model continues, but there is no debate about how the advent of magnetic resonance imaging (MRI) has increased awareness of many additional brain regions that are active during dreaming. Contemporary research has utilized MRIs to provide a window into dream-related brain activity, showing high levels of activation in brain regions associated with feeling emotions, creating movements, and comprehending visual scenery (Figure 5.11). Surprisingly, some of the brain structures, such as the amygdala, anterior cingulate gyrus, and hippocampus—parts of the “emotional brain” or limbic system—are even more active during dreaming than when we are processing information in our waking state.
In sharp contrast to the activation-synthesis model, neuropsychologist Mark Solms proposes that dreams are created in the cerebral cortex, specifically the ventromedial prefrontal cortex (Figure 5.12). This part of the brain is involved in a range of functions such as goal-seeking, regulating challenging emotions, recognizing facial expressions, and processing risk. It also provides connections between the limbic system and the frontal cortex. In the early half of the twentieth century, this was one of the brain regions destroyed in attempts to treat mental illness. Solms found that patients with damage to this area, whether from surgeries or other injuries, did not dream.
In this chapter, we are focused primarily on REM dreams, but let’s briefly consider the activity of the limbic system during NREM dreams, which we know are bland and lacking in emotion. So it follows that the limbic system is quite mellow during NREM dreams.
On the other hand, it turns out, if we look further, that there are brain areas that become inactive during REM dreams as well. When we consider the bizarre and sometimes embarrassing things we do in REM dreams, the deactivation of one of these brain regions in particular makes perfect sense: the prefrontal cortex, which guides you to use good judgment and be sensible and socially appropriate, has exceptionally low activity during dreaming (Figure 5.13). Another area that seems to almost drop out of the game during REM dreaming is the primary visual cortex. This region of your brain is involved in consciously detecting visual stimuli from your eyes, so it is logical that, since your eyes are closed while dreaming, the primary visual cortex has almost no activity at that time. The brain is still able to generate visual content for dreams, as it still relies on the visual association cortex—the part of the brain that processes more complex visual information.
Rather than looking at particular brain structures for the source of dreams, Harvard Medical School sleep researcher Robert Stickgold asked participants to look at the events and emotions of their days for the source of dream content. Participants kept diaries of their daytime activities and their dreams. The dreams were not a replay of daytime events. However, the worries and emotional themes of the day were often incorporated into the dreams. If we leave the activation-synthesis model behind in favor of theories such as Stickgold’s, suggesting dreams contain meaningful information, then it’s time to move to the next section for a discussion of how to interpret dreams.10
Interpretation of Dreams
Over five thousand years ago in Mesopotamia, people were having their dreams interpreted and looking to them for divine guidance (Figure 5.14). Throughout the years and around the world, dream interpreters and sometimes priests have been trusted to translate dream content into something meaningful for the dreamer. With the emergence of the discipline of psychology in the nineteenth century, the practice began to include psychologists as interpreters as well.
Sigmund Freud, an Austrian neurologist, believed dreams contained symbolic information requiring interpretation by an expert. He thought dream content would be too disturbing for the dreamer. For example, the dreamer may feel too ashamed to admit to a fantasy they are having, so the content has to come to the dreamer in symbols. (It was convenient for Freud that he, as a self-proclaimed expert, could charge people money for these interpretations.) According to his approach, dreams contain two categories of content: manifest and latent. Manifest content is the obvious material from the dream—the way the dreamer would describe the dream. Latent content is the hidden material that indicates the dreamer’s secret desires and fears. These repressed feelings, once revealed in a dream analysis session, could be used to identify and treat a person’s problems. There is great value in exploring and analyzing dream content, but Freud’s particular method of dream interpretation has been put to the test by scientific studies that have shown that different experts using his technique will come up with vastly different conclusions about the meaning of the same dream. These studies suggest a lack of reliability in his approach to dream analysis.
A psychiatrist colleague of Freud’s, Carl Jung, disagreed with Freud on the need for dreams to be deciphered. Jung was convinced that the same symbol means something different to each person, so there was no use in trying to create a book of dream symbols that could be applied as a part of dream analysis. Instead, Jung thought our instincts convey wisdom to our rational mind via dreams. He said we were disconnected from nature and our instincts because of modern society, so we should use our dreams to reconnect and be transformed.
At around the same time that Freud and Jung were placing emphasis on the deep psychological meaning of dreams, Mary Whiton Calkins, a pioneer in psychology, was developing an opposing theory. As a part of her project at Clark University in Massachusetts, she examined over two hundred dream reports and concluded that dream content is closely related to recent experiences, almost like a related replay of the day’s events and sensations, and that dreams do not contain hidden meaning. She said, “In fact, my study as a whole must be rather contemptuously set down by any good Freudian as superficially concerned with the mere ‘manifest content’ of the dream.” Calkins must have been courageous not only for challenging conventional wisdom about dreams but because she was attending psychology seminars at Harvard with special permission, since women were not often allowed at the then all-male college. She even fulfilled all the requirements for a doctorate in psychology at Harvard, receiving high recommendations from professors, including William James, but the institution still refused to grant her the degree since she was a woman. However, she went on to Wellesley College, where she created a psychology lab—one of the first in the nation—and became the first woman to serve as president of the American Psychological Association, soaring beyond Harvard’s discriminatory policy.
Dreams in Different Cultures
Looking around the world to consider diverse attitudes about dreams, a common theme is that many view dreaming as an opportunity to connect with the divine. In the Quran, one type of dream is called ru’ya. Rather than being created by the dreamer’s mind, a ru’ya comes from God or the angels, and therefore a ru’ya is believed to have a purpose and meaning. There is a parallel in Hawaiian culture in that dreams from spirits are thought to have significance, in contrast to dreams the dreamer created, which are thought to be meaningless and pupule (crazy). In Hawaiian tradition, dreams are part of the bond between the spirits of those who are living and those who have passed. While a living person is dreaming, the spirit leaves the body through the luaʻuhane (“pit for the spirit,” which is our tear duct) and travels to receive guidance from ʻaumākua (ancestral guardian spirits) and akua (gods).
Ancient Egyptians also used dreams to travel in their dream body and connect with gods and the spirits of the departed. People would visit the temple of a god or goddess, such as the goddess Isis (who has nothing to do with the Islamic State terrorist group) for dream interpretation or incubation (Figure 5.16). The dreamer might spend days preparing for dream incubation—a time to encourage dreams rich in guidance—by purifying themselves through ritualistic bathing, fasting, and praying before sleeping in a temple. After awakening from the dream, an oracle would be available to interpret the dream, which was especially valuable, since one of the strategies was to interpret dream content as the exact opposite of its literal meaning. The temples were also available for visitors who had slept and dreamt at home to consult with priests on dream interpretation.
Lucid Dreaming
Bringing awareness that we are dreaming into the middle of a dream, opens another world for learning, creativity, resolving trauma, and more. Lucid dreaming refers to the conscious realization that we are dreaming while still remaining asleep and deep in the dream. Taking things one step further, a person who is lucid dreaming can learn to control the content and progression of the dream. This control is particularly beneficial when working with persistent nightmares because dream scenery and outcomes can be resolved and transformed into something pleasant.
Here are some steps to take if you would like to learn to lucid dream:
Conducting a Dream Group
This is best done in a group of four to six people seated in a circle but is still satisfying and productive in groups of different sizes (Figure 5.18). It is reassuring to state at the beginning that nothing shared in the group will be discussed outside of the group. Everyone is responsible for keeping the group on track with the steps, but it is helpful to designate a leader to take that responsibility. A different person takes over the role of leader when the group finishes all the steps and finishes the analysis of one dream before moving on to the next person’s dream. Revelations about each dream’s meaning will arise throughout the process, usually in pieces, and the interpretation discussion can continue without structure after the final step. The group should work on one dream at a time, going through all the steps and including the final open discussion about interpretation before moving on to the next person and their dream.
1 Deirdre Barrett, ed., Trauma and Dreams (Cambridge, MA: Harvard University Press, 2001), 282.
2 R. D. Cartwright et al., “REM Latency and the Recovery from Depression: Getting Over Divorce,” American Journal of Psychiatry 148, no. 11 (November 1991): 1530–35, https://doi.org/10.1176/ajp.148.11.1530 .
3 Barrett, Trauma and Dreams , 282.
4 “National Suicide Prevention Lifeline,” accessed on December 3, 2021, https://suicidepreventionlifeline.org/ .
5 Erin J. Wamsley and Robert Stickgold, “Memory, Sleep, and Dreaming: Experiencing Consolidation,” Sleep Medicine Clinics 6, no. 1 (March 2011): 97–108, https://doi.org/10.1016/j.jsmc.2010.12.008 .
6 Antti Revonsuo and Katja Valli, “Dreaming and Consciousness: Testing the Threat Simulation Theory of the Function of Dreaming,” Psyche 6 (October 2000), www.researchgate.net/publication/232499090_Dreaming_and_consciousness_Testing_the_threat_simulation_theory_of_the_function_of_dreaming.
7 “Faculty: Gina Poe,” UCLA: Integrative Biology & Physiology, accessed June 6, 2021, https://www.ibp.ucla.edu/faculty/gina-poe/ .
8 W. E. Burghardt Du Bois, “A Great Woman,” Crisis 18, no. 3 (July 1919): 131, https://modjourn.org/issue/bdr512386/ .
9 Ullrich Wagner et al., “Sleep Inspires Insight,” Nature 427, no. 6972 (January 2004): 352–55, https://doi.org/10.1038/nature02223 .
10 Magdalena J. Fosse et al., “Dreaming and Episodic Memory: A Functional Dissociation?,” Journal of Cognitive Neuroscience 15, no. 1 (January 2003): 1–9, www.researchgate.net/publication/10896475_Dreaming_and_Episodic_Memory_A_Functional_Dissociation.