Dreams of Meaning
We sleep. We dream. We do not know why.
Faith traditions have interpreted sleep and dreams as meaningful for millennia without the need for scientific grounding, though. Dreams are visits from angels, attacks by devils, and revelation from the divine. Some dreams predict the future while others seem like spiritual exhaust from the day. Dreams drove the Buddha toward enlightenment and saved Egypt from seven years of famine. They propelled Sigmund Freud to stardom through his writings on sublimated wish fulfillment and the royal road to the unconscious.
But the last century has shown a shift in focus from decoding dream content to mapping neuroanatomy, and the past two decades have produced much of the technology needed to begin preliminary exploration. When we sleep, proteins knit cells together, growth hormones release, and our bodies paralyze to give our brains room to roam without physically acting out dreams. When it comes right down to itâ€”we spend one third of our lives doing something the medical community currently understands only in scraps and pieces. Sleep researchâ€”and the cognitive sciences that engage in itâ€”are young but promising. Each new breakthrough drives this kind of question to the fore: If we can map the neurological processes correlated with dreaming, do dreams lose their religious meaning along the way?
I respond with a resounding no, but we need at least a cereal box understanding of neuroscience and memory before we can discuss why. Three years ago, Comedy Centralâ€™s Stephen Colbert opened his interview with cognitive scientist, Steven Pinker, like this: â€œYour specialty is the brain and how it works, right? Itâ€™s a complicated subject, so how does the brain work?â€ Colbert paused. â€œFive words or less.â€ Pinker did not miss a beat. He counted his answer out on his fingers: â€œBrain. . . cells. . . fire. . . in. . . patterns.â€ Five words or less? Pinkerâ€™s neurons fired fast.
Every neurological pattern is at least tethered to physical perception. Light bounces off of a dark liquid, my eyes translate that light into electrical impulses cascading across my optic nerves, and those impulses trigger patterns in my brain. The liquid looks black and slick in a brown ceramic mug. It feels hot against my palms and smells like rich soil. When I drink it, it tastes bitter and beautiful. Multiple senses package together into a seamless bundle of experience in my brain, and I label this liquid: coffee. Every sensory experience in our livesâ€”from an insignificant sip of coffee to burying someone we love in the groundâ€”enters our brains through sensory perception, and our neurons stitch memories together as patterns to match. Each bit of sensory input stores in distributed networks, soâ€”when we recall past memoriesâ€”we recreate thoughts by pulling together spare parts and knitting them back together.
This means that memory and imagination are the same neurological process. I can remember a horse, and I can remember an eagle, so I can imagine Pegasus. We human beings can borrow pieces of memory to knit something else together entirely. Einstein called the process combinatory play. Imagination makes it possible to forget most of lifeâ€™s minutia and then reconstruct memories of that minutia from scratch anyway. Do you need to remember the exact taste of your toothpaste each morning? The discrete texture of every doorknob you have ever touched? Of course you donâ€™t. You retain enough details to approximate these memories, and then you fill in the gaps with spare parts. You imagine. You borrow legs from this horse and wings from that eagle to form a composite memory. The taste of toothpaste that comes to mind from this morning is a collage of past experiences filling in the unimportant gaps in memory.
At some point in human history, our distant ancestors learned to recognize fruit as ripe by its color and texture. As a species, we track patterns in our surroundings and attribute meaning to those patterns. Soft means sweet. Warm coffee means comfort. I take my coffee without cream or sugar, so each sip should be bitter. The sensations wrapped up in drinking coffee couple with my history of insomnia and my deep love for all things warm to form a framework of expectation. Each confirmation digs those patterns deeper. We modulate pattern recognition into consolidated forms of memory, too. We inherit instinct, but intuition acts as a deep form of memory that allows accelerated responses to our surroundings based on previous experience. This means that we often connect the dots intuitively long before we recognize patterns consciously.
Neurons, memory, and intuition. Now we have the tools to engage at least one contemporary scientific dream theory:dreaming is an experience of memory consolidation. When we sleep, we shut off access to the outside world and all of the new memories it might offer. We turn inward. In this theory, dreams works like a multidimensional Etch A Sketch. Some lines shake out of view while others darken. Our brains mull over our experiences and draw connections without having to worry about bombardment by new stimuli. When we wake up, the Etch A Sketch dials start turning new lines to match experience again. Dreams strengthen some neurological patterns and erase others, modulating memories and connecting present experiences to past expectations, fitting the dayâ€™s internal and external memories into the deeper framework of intuition.
Matthew Wilson is a researcher at MITâ€™s Center for Learning and Memory. He monitored neurological patterns in ratsâ€™ brains while they navigated a maze, and then he found the same networks firing in the same order while they slept. The hippocampus, which helps with memory formation, lit up while the rats slept as well. They modulated memories of the mazes into faster, more efficient responses. When Wilson sent the rats through two mazes instead of just one, he noticed that they began combining neurological networks associated with both mazes while they slept. On a very rudimentary level, they seemed to create hypothetical mazes and practice twisting and turning to anticipate quick responses to future problems.
Dreams become combinatory play. Experiences bundle together during the day, and those connections loosen to reconfigure during sleep. When we dream, imagination has more room to play and make sense of the dayâ€™s experiences as conscious and non-conscious memories blend across deeply modulating levels. The process takes place during different phases of sleep as well, not simply during REM. Our brains shut off access to new sensory information and get to work tackling internal problems from new angles.
Robert Stickgold is a professor of psychiatry at Harvard Medical School. He believes that we mentally flag emotional and repetitious memories during the day and then review those memories again during sleep. His theory works like this: The first stage of dreaming filters out some memories as important and others as disposable. The distinct taste of toothpaste is insignificant. It is disposable. Perhaps you practiced piano for an hour this morning, though. Repetition flags that as important. Maybe you also arrived late to work, and your boss made a demeaning comment. The emotional rupture becomes as important as well.
The second phase pairs flagged experiences with deeper mental frameworks. How do playing the piano and anxiety at work fit into what you already know? Your brain experiments. It engages combinatory play. It works toward efficiency. Perhaps you practice the piano on an airplane in your dream as memories combineâ€”as patterns blur and intersect. Do piano-playing and airplane-riding pair well together? Maybe not. But patterns begin hitting matches in the deeper framework as the night progresses. Your boss was snide when you walked in lateâ€”just like your fifth grade teacher one morning when you arrived to class lateâ€”and emotional boundaries pile, intermingle, and overlap. They match. Your boss stands in front of the chalkboard and embarrasses you in your fifth grade classroom. Your entrenched expectations of authority figures blend together, and the dream becomes an imagined memory that you experience while you sleep. Neurological patterns shift to match current experience and past expectations, and then those memories consolidate and modulate into deeper intuition to anticipate the future. In this approach, both sleep and waking life become encoded rather than decoded. After dreaming, we will recognize fruit as ripe or bitter faster in the future. Stickgold and his colleagues are rapidly gaining experimental support for their theory.
We all dream every night whether we consciously remember it or not, andâ€”when we dreamâ€” boundaries blend, physical laws break, and imagination combines experiences freely. Emotional potency from dreams often spills over into waking life, too, and haunts us throughout the day. Dreams open windows into the self that often remain closed when we are awake. They force us to face difficult questions every night of our lives and engage imagination in response. Few other experiences can drive us to search ourselves so deeply and detach us from what we think we know so successfullyâ€”meditation, prayer, or a particularly moving liturgy, maybeâ€”but the experience of dreaming often feels spiritual whether or not dreamers know about brain cells firing patterns. Now: if we can map the neurological processes correlated with dreaming, do dreams lose their religious meaning along the way? It would be overly ambitious to say that we can comprehensively explain anything relating to the brain at this point, but the need for an answer still seems imminent.
This sort of question is not unique to dreams; it has plagued every area of human experience for centuries. How did humans come to be? God. Until evolution. How did the cosmos come to be? God. Until the Big Bang. When gaps in understanding of physical processes disappear, many peopleâ€™s God goes with them. Their sense of meaning diffuses like breath in the wind. In the future: if we can map the neurological processes correlated with waking experience, does all of life lose its religious meaning along the way, too?
I will leave debates about ideals and absolutes to Plato and Nietzsche for now and focus on what we can engage as internal participants in social systems instead. Academia and popular culture have treated science and religion as separate categories at least since both underwent revolutions and reformations and counter-revolutions and counter-reformations and cultural cross-pollinations some centuries ago. We might treat science and religion as separate categories nowâ€” at least on paperâ€”but those categories do not need to compete for primacy. They approach the same experienceâ€”dreaming in this caseâ€”from different angles and evaluate it using different criteria. Placing them in competition shows misunderstanding of both.
Brains interpret signals from the outside world during waking life, and they filter those signals into deeper patterns during sleep. Religious interpretations have accompanied dreams for millennia, but religious interpretations have accompanied all human experience for millennia. If we throw out religious significance for dreams because we can describe physiological processes, then we also have to throw out religious significance for waking life, whenever we can describe light bouncing off of coffee cups. Describing the mechanism does not displace the meaningâ€”unless the meaning can live under cover of absolute mystery. I wonâ€™t stop driving simply because I learn how car engines run. (Human brains are exponentially more complex than car engines, but all analogies are limited.) The experience of dreaming becomes no less magical when the scientists outline neurological underpinnings. I have no doubt that Stickgoldâ€™s dream life is as rich now as the Buddhaâ€™s was long before EEGâ€™s. If we understand physical processes wellâ€”or at least if we experiment with increasing accuracyâ€”then we create better opportunities to map meaning onto our sensory experiences of the world. Dreams are one especially liminal, liquid example.
Scientific paradigms shift with new information. Religious paradigms can, too. We need not assume that life is devoid of meaning simply because someone discovers a new gene therapy or documents a new pulsar. We map meaning onto these patterns. Our species has noticed fruit ripe for the picking for quite some time now; recognizing rhythms embedded in the cosmos can only make the potential for meaning all the sweeter.
 J. Allan Hobson, Dreaming: An Introduction to the Science of Sleep (Oxford; New York: Oxford University Press, 2002), 1.
 Daniel J. Siegel, The Developing Mind : How Relationships and the Brain Interact to Shape Who We Are (New York: Guilford Press, 1999), 37.
 Sidarta Ribeiro, Damien Gervasoni, and Miguel A.L. Nicolelis, “Neuronal Reverberation and the Consolidation of New Memories across the Wake-Sleep Cycle,” in Sleep Circuits and Functions, ed. Sidney A Simon and Miguel A.L. Nicolelis (Boca Raton, Florida: CRC Press, 2005), 201, 216; Mircea Steriade, “Sleep and Neuronal Plasticity: Cellular Mechanisms of Corticothalamic Oscillations,” in Sleep Circuits and Functions, ed. Sidney A Simon and Miguel A.L. Nicolelis(Boca Raton, Florida: CRC Press, 2005), 2, 18.
Hobson, J. Allan. Dreaming : An Introduction to the Science of Sleep. Oxford ; New York: Oxford University Press, 2002.
Ribeiro, Sidarta, Damien Gervasoni, and Miguel A.L. Nicolelis. “Neuronal Reverberation and the Consolidation of New Memories across the Wake-Sleep Cycle.” In Sleep Circuits and Functions, edited by Sidney A Simon and Miguel A.L. Nicolelis. Boca Raton, Florida: CRC Press, 2005.
Siegel, Daniel J. The Developing Mind : How Relationships and the Brain Interact to Shape Who We Are. New York: Guilford Press, 1999.
Steriade, Mircea. “Sleep and Neuronal Plasticity: Cellular Mechanisms of Corticothalamic Oscillations.” In Sleep Circuits and Functions, edited by Sidney A Simon and Miguel A.L. Nicolelis. Boca Raton, Florida: CRC Press, 2005.