The Marginalian
The Marginalian

What Birds Dream About: How Evolution Invented REM in the Avian Brain So We May Practice the Possible in Our Sleep

This essay originally appeared in The New York Times

I once dreamed a kiss that hadn’t yet happened. I dreamed the angle at which our heads tilted, the fit of my fingers behind her ear, the exact pressure exerted on the lips by this transfer of trust and tenderness.

Freud, who catalyzed the study of dreams with his foundational 1899 treatise, would have discounted this as a mere chimera of the wishful unconscious. But what we have since discovered about the mind — particularly about the dream-rich sleep state of rapid-eye movement, or REM, unknown in Freud’s day — suggests another possibility for the adaptive function of these parallel lives in the night.

Yellow-crowned night heron “divination” from An Almanac of Birds: 100 Divinations for Uncertain Days, also available as a stand-alone print.

One cold morning not long after the kiss dream, I watched a young night heron sleep on a naked branch over the pond in Brooklyn Bridge Park, head folded into chest, and found myself wondering whether birds dream.

The recognition that nonhuman animals dream dates at least as far back as the days of Aristotle, who watched a sleeping dog bark and deemed it unambiguous evidence of mental life. But by the time Descartes catalyzed the Enlightenment in the 17th century, he had reduced other animals to mere automatons, tainting centuries of science with the assumption that anything unlike us is inherently inferior.

In the 19th century, when the German naturalist Ludwig Edinger performed the first anatomical studies of the bird brain and discovered the absence of a neocortex — the more evolutionarily nascent outer layer of the brain, responsible for complex cognition and creative problem-solving — he dismissed birds as little more than Cartesian puppets of reflex. This view was reinforced in the 20th century by the deviation, led by B.F. Skinner and his pigeons, into behaviorism — a school of thought that considered behavior a Rube Goldberg machine of stimulus and response governed by reflex, disregarding interior mental states and emotional response.

Archaeopteryx specimen, Natural History Museum, Berlin. (Photograph: H. Raab)

In 1861, just two years after Darwin’s publication of On the Origin of Species, a fossil was discovered in Germany with the tail and jaws of a reptile and the wings and wishbone of a bird, sparking the revelation that birds had evolved from dinosaurs. We have since learned that, although birds and humans haven’t shared a common ancestor in more than 300 million years, a bird’s brain is much more similar to ours than to a reptile’s. The neuron density of its forebrain — the region engaged with planning, sensory processing, and emotional responses, and on which REM sleep is largely dependent — is comparable to that of primates. At the cellular level, a songbird’s brain has a structure, the dorsal ventricular ridge, similar to the mammalian neocortex in function if not shape. (In pigeons and barn owls, the DVR is structured like the human neocortex, with both horizontal and vertical neural circuitry.)

Art by Jackie Morris from The Lost Spells

Still, avian brains are also profoundly other, capable of feats unimaginable to us, especially during sleep: Many birds sleep with one eye open, even during flight. Migrating species that traverse immense distances at night, like the bar-tailed godwit, which covers the 7,000 miles between Alaska and New Zealand in eight days of continuous flight, engage in unihemispheric sleep, blurring the line between our standard categories of sleep and wakefulness.

But while sleep is an outwardly observable physical behavior, dreaming is an invisible interior experience as mysterious as love — a mystery to which science has brought brain imaging technology to illuminate the inner landscape of the sleeping bird’s mind.

The first electroencephalogram of electrical activity in the human brain was recorded in 1924, but EEG was not applied to the study of avian sleep until the 21st century, aided by the even more nascent functional magnetic resonance imaging, developed in the 1990s. The two technologies complement each other. In recording the electrical activity of large populations of neurons near the cortical surface, EEG tracks what neurons do more directly. But fMRI. can pinpoint the location of brain activity more precisely through oxygen levels in the blood. Scientists have used these technologies together to study the firing patterns of cells during REM sleep in an effort to deduce the content of dreams.

Zebra finch by F. W. Frohawk, 1899. (Available as a print and as stationery cards, benefitting The Audubon Society)

A study of zebra finches — songbirds whose repertoire is learned, not hard-wired — mapped particular notes of melodies sung in the daytime to neurons firing in the forebrain. Then, during REM, the neurons fired in a similar order: The birds appeared to be rehearsing the songs in their dreams.

An fMRI study of pigeons found that brain regions tasked with visual processing and spatial navigation were active during REM, as were regions responsible for wing action, even though the birds were stilled with sleep: They appeared to be dreaming of flying. The amygdala — a cluster of nuclei responsible for emotional regulation — was also active during REM, hinting at dreams laced with feeling. My night heron was probably dreaming, too — the folded neck is a classic marker of atonia, the loss of muscle tone characteristic of the REM state.

But the most haunting intimation of the research on avian sleep is that without the dreams of birds, we too might be dreamless. No heron, no kiss.

The passenger pigeon by John James Audubon, 1842. (Available as a print and as stationery cards, benefitting The Audubon Society.)

There are two primary groups of living birds: the flightless Palaeognathae, including the ostrich and the kiwi, which have retained certain ancestral reptilian traits, and Neognathae, comprising all other birds. EEG studies of sleeping ostriches have found REM-like activity in the brainstem — a more ancient part of the brain — while in modern birds, as in mammals, this REM-like activity takes place primarily in the more recently developed forebrain.

Several studies of sleeping monotremes — egg-laying mammals like the platypus and the echidna, the evolutionary link between us and birds — also reveal REM-like activity in the brainstem, suggesting that this was the ancestral crucible of REM before it slowly migrated toward the forebrain.

If so, the bird brain might be where evolution designed dreams — that secret chamber adjacent to our waking consciousness where we continue to work on the problems that occupy our days. Dmitri Mendeleev, after puzzling long and hard over the arrangement of atomic weights in his waking state, arrived at his periodic table in a dream. “All the elements fell into place as required,” he recounted in his diary. “Awakening, I immediately wrote it down on a piece of paper.” Cosmologist Stephon Alexander dreamed his way to a groundbreaking insight about the role of symmetry in cosmic inflation that earned him a national award from the American Physics Society. For Einstein, the central revelation of relativity took shape in a dream of cows simultaneously jumping up and moving in wavelike motion.

Art by Tom Seidmann-Freud — Sigmund Freud’s niece — for the philosophical 1922 children’s book David the Dreamer

As with the mind, so with the body. Studies have shown that people learning new motor tasks “practice” them in sleep, then perform better while awake. This line of research has also shown how mental visualization helps athletes improve performance. Renata Adler touches on this in her novel Speedboat: “That was a dream,” she writes, “but many of the most important things, I find, are the ones learned in your sleep. Speech, tennis, music, skiing, manners, love — you try them waking and perhaps balk at the jump, and then you’re over. You’ve caught the rhythm of them once and for all, in your sleep at night.”

It may be that in REM, this gloaming between waking consciousness and the unconscious, we practice the possible into the real. It may be that the kiss in my dream was not nocturnal fantasy but, like the heron’s dreams of flying, the practice of possibility. It may be that we evolved to dream ourselves into reality — a laboratory of consciousness that began in the bird brain.

BP

How Patterns Change

How Patterns Change

“There is no description of a life without an account of the changes that are possible within it,” Adam Philips writes in his superb meditation on our ambivalent desire for change — ambivalence brilliantly rendered in the Vampire Problem thought experiment, illustrating the paradoxical psychology of why have such a hard time changing, breaking the patterned ways of being by which we hedge against the fear of not knowing who we are, what we want, and how to be safe.

Our paradox is that we are the pattern-seeking animal — a kind of superpower conferred upon us by our complex consciousness, which came with a high price. Like the hero of the Greek myths eternally bedeviled by his tragic flaw, we pay for our power with our vulnerability. The patterns we discover — fractals, the harmonic scale, the laws of planetary motion — give us a firmer foothold on reality, set us free to know the world as it really is, in all its fearsome unknowns. But the patterns we invent — in our habits, in our relationships, in our myths and power structures and organizing principles of civilization — cage us, stiffen us with certainty until we grow too ossified to change.

Art from An Almanac of Birds: 100 Divinations for Uncertain Days, also available as a stand-alone print.

In a world doing its best to make us mistake being sure for being safe, living with the courage of uncertainty — the courage to break the pattern of the familiar in order to release the possible — is a radical act, an act not only of resistance but of redemption. The building blocks and practice of that courage, as an antipode to the reflex of fear, are what therapist, teacher, and organizer Prentis Hemphill reflects on in the inaugural episode of trauma therapist Mariah Rooney’s wonderful MOVD podcast:

The fear is absolutely there, and the fear is often the driver toward isolation, toward my old patterning, toward the thing I think will keep me comfortable and alleviate the fear. But what changes our patterns, ultimately, is the courage to feel that fear and do something different anyway. You step into the unknown and you don’t know what is going to happen — that is the act of courage.

This reorientation is not merely a cerebral decision but an embodied action — something that renders the courage to change, or simply the courage to get real, all the more difficult and all the more urgent in a neo-Cartesian culture that keep driving us further and further away from the lush life of the body as disembodied artificial intelligences make more and more decisions for us and the real world — the world of fireflies and owls and lichen, trembling with aliveness — takes up less and less space in our mental model of reality. Hemphill celebrates this necessary reclamation of the body as the instrument of transformation:

Everything that we do towards recovering aspects of ourselves that we have disowned or parts of our body that we have vacated, every act that we take where we work through and with the fear rather than succumb to the isolation that fear recommends — those are the moments where we start to change our patterning.

Art by Charlie Mackesy from The Boy, the Mole, the Fox and the Horse

In What It Takes to Heal: How Transforming Ourselves Can Change the World (public library), Hemphill considers the psychophysiology that makes fear such a powerful default:

When what we face overwhelms our ability to respond and/or to escape unscathed, or when we are given the message to suppress the body’s reactions, our nervous systems don’t know that the traumatic experience has ended, and our survival response continues to exist in our bodies. We live then in a near-constant state of reaction, either scanning for an indication that the threat has returned or reproducing aspects of the experience in our relationships and lives in what many understand to be an attempt to complete the threat we feel. It is alive in our tissues, our muscles, our thoughts, and our moods. It lives on in our behavioral patterns, our habits, what we do and don’t do, what we say and what we are afraid to say… You can have a region of your body living out of time, out of step, with the rest of you… A physiological memory from ten or twenty years earlier can be lodged in the structure of your fasciae, and therefore in your actions and relationships… Trauma stays… lingers long past its welcome in our bodies.

Against this backdrop, courage may just be the refusal to partition ourselves, to vacate our embodiment or cede it to our ideas about what life should look like, ideas programmed by our unexamined and uncontested defaults. Insisting that “every inch of progress, every ounce of love, every truly meaningful action from here on out will happen through courage, not comfort,” Hemphill writes:

Courage changes things and courage changes us. It’s how we become. I have found that there is a “right-sized” fear inside any vision for change, and in taking courageous action we develop a part of ourselves that can talk back to and hold the fear without letting it lead… The courage we need is the courage to fail and stay… The courage to exit the safety of our dying delusions… The courage to surrender… The courage to love and be loved.

Complement with George Saunders on the courage of uncertainty and how to unbreak our hearts by breaking our patterns, then revisit Charlie Mackesy’s wondrous watercolor meditation on how to bear your fear and what it means to love.

BP

Necessary Losses: The Life-Shaping Art of Letting Go

Necessary Losses: The Life-Shaping Art of Letting Go

“The art of losing isn’t hard to master,” Elizabeth Bishop wrote in one of the great masterpieces of poetry. “Every mortal loss is an Immortal Gain,” William Blake wrote two centuries before her in his beautiful letter to a bereaved father.

We dream of immortality because we are creatures made of loss — the death of the individual is what ensured the survival of the species along the evolutionary vector of adaptation — and made for loss: All of our creativity, all of our compulsive productivity, all of our poems and our space telescopes, are but a coping mechanism for our mortality, for the elemental knowledge that we will lose everything and everyone we cherish as we inevitably return our borrowed stardust to the universe.

And yet the measure of life, the meaning of it, may be precisely what we make of our losses — how we turn the dust of disappointment and dissolution into clay for creation and self-creation, how we make of loss a reason to love more fully and live more deeply.

“Broken/hearted” by Maria Popova. (Available as a print.)

That is what Judith Viorst explores in her 1987 consolation of a book Necessary Losses (public library) — an inquiry into the profound and far-reaching relationship between our losses and our gains, revealing renunciation as a fulcrum of growth. She paints the vast landscape of loss upon which life plays out:

When we think of loss we think of the loss, through death, of people we love. But loss is a far more encompassing theme in our life. For we lose not only through death, but also by leaving and being left, by changing and letting go and moving on. And our losses include not only our separations and departures from those we love, but our conscious and unconscious losses of romantic dreams, impossible expectations, illusions of freedom and power, illusions of safety — and the loss of our own younger self, the self that thought it always would be unwrinkled and invulnerable and immortal.

[…]

These necessary losses… we confront when we are confronted by the inescapable fact… that we are essentially out here on our own; that we will have to accept — in other people and ourselves — the mingling of love with hate, of the good with the bad;… that there are flaws in every human connection; that our status on this planet is implacably impermanent; and that we are utterly powerless to offer ourselves or those we love protection — protection from danger and pain, from the in-roads of time, from the coming of age, from the coming of death; protection from our necessary losses.

These losses are a part of life — universal, unavoidable, inexorable. And these losses are necessary because we grow by losing and leaving and letting go.

As a sculpture is shaped by what is chiseled off from the block of stone, so too are we shaped by what we lose — by choice, with all the complexities and difficulties of letting go, or by the scythe of chance, which takes away as impartially as it gives. Viorst writes:

The road to human development is paved with renunciation. Throughout our life we grow by giving up. We give up some of our deepest attachments to others. We give up certain cherished parts of ourselves. We must confront, in the dreams we dream, as well as in our intimate relationships, all that we never will have and never will be. Passionate investment leaves us vulnerable to loss. And sometimes, no matter how clever we are, we must lose… It is only through our losses that we become fully developed human beings.

Art by Giuliano Cucco from Before I Grew Up — a soulful illustrated elegy for loss and our search for light

We enter the realm of loss the moment the umbilical cord is cut to sever what Viorst calls the “blurred-boundary bliss of mother-child oneness” — the primal loss that sets off the ongoing task of becoming ourselves. From this origin point, she traces the lifelong vector of losses and gains:

Exchanging the illusion of absolute shelter and absolute safety for the triumphant anxieties of standing alone… we become a moral, responsible, adult self, discovering — within the limitations imposed by necessity — our freedoms and choices. And in giving up our impossible expectations, we become a lovingly connected self, renouncing ideal visions of perfect friendship, marriage, children, family life for the sweet imperfections of all-too-human relationships. And in confronting the many losses that are brought by time and death, we become a mourning and adapting self, finding at every stage — until we draw our final breath — opportunities for creative transformations.

In a sentiment the poet Mark Doty would echo — “you need to both remember where love leads and love anyway,” he wrote in his beautiful reckoning with love and loss — she adds:

We cannot deeply love anything without becoming vulnerable to loss. And we cannot become separate people, responsible people, connected people, reflective people without some losing and leaving and letting go.

Complement Necessary Losses, which goes on to explore the many regions of loss in human life and how they can become frontiers of growth, with Hannah Arendt on learning how to live with the fundamental fear of loss, Thoreau on living through a loss, and Alan Watts on learning not to think of gain and loss, then explore two uncommon lenses on loss: fractals and chlorophyll.

BP

The Other Significant Others: Living and Loving Outside the Confines of Conventional Friendship and Compulsory Coupledom

The Other Significant Others: Living and Loving Outside the Confines of Conventional Friendship and Compulsory Coupledom

We move through the world largely unaware that our emotions are made of concepts — the brain’s coping mechanism for the blooming buzzing confusion of what we are. We label, we classify, we contain — that is how we parse the maelstrom of experience into meaning. It is a useful impulse — without it, there would be no science or storytelling, no taxonomies and theorems, no poems and plots. It is also a limiting one — the most beautiful, rewarding, and transformative experiences in life transcend the categories our culture has created to contain the chaos of consciousness, nowhere more so than in the realm of relationships — those mysterious benedictions that bridge the abyss between one consciousness and another.

When we hollow the word friend by overuse and misuse, when we make of love a contract with prescribed roles and rigid, impossible expectations, we become prisoners of our own concepts. The history of feeling is the history of labels too small to contain the loves of which we are capable — varied and vigorously transfigured from one kind into another and back again. It takes both great courage and great vulnerability to live outside concepts, to meet each new experience, each new relationship, each new emotional landscape on its own terms and let it in turn expand the terms of living.

Art by Sophie Blackall from Things to Look Forward to

That is what Rhaina Cohen explores in The Other Significant Others: Reimagining Life with Friendship at the Center (public library) — a journalistic investigation of the vast yet invisible world of unclassifiable intimate relationships, profiling pairs of people across various circumstances and stages of life sustained by such bonds, people who have “redrawn the borders of friendship, moving the lines further and further outward to encompass more space in each other’s lives,” people who have found themselves in finding each other.

What emerges through this portrait of a type of relationship “hidden in plain sight” is an antidote to the tyranny of the “one-stop-shop coupledom ideal” and “an invitation to expand what options are open to us,” radiating a reminder that we pay a price for living by our culture’s standard concepts:

While we weaken friendships by expecting too little of them, we undermine romantic relationships by expecting too much of them.

A generation after Andrew Sullivan celebrated the rewards of friendship in a culture obsessed with romance, Cohen writes:

This is a book about friends who have become a we, despite having no scripts, no ceremonies, and precious few models to guide them toward long-term platonic commitment. These are friends who have moved together across states and continents. They’ve been their friend’s primary caregiver through organ transplants and chemotherapy. They’re co-parents, co-homeowners, and executors of each other’s wills. They belong to a club that has no name or membership form, often unaware that there are others like them. They fall under the umbrella of what Eli Finkel, a psychology professor at Northwestern University, calls “other significant others.” Having eschewed a more typical life setup, these friends confront hazards and make discoveries they wouldn’t have otherwise.

Illustration by Maurice Sendak from a vintage ode to friendship by Janice May Udry

Noting that her interest in the subject is more than theoretical, catalyzed by her own expansive relationship with another woman in parallel with her marriage, Cohen considers these category-defying bonds as a countercultural act of courage and resistance:

I began to see how these unusual relationships can also be a provocation — unsettling the set of societal tenets that circumscribe our intimate lives: That the central and most important person in one’s life should be a romantic partner, and friends are the supporting cast. That romantic love is the real thing, and if people claim they feel strong platonic love, it must not really be platonic. That adults who raise kids together should be having sex with each other, and marriage deserves special treatment by the state.

With an eye to the long lineage of people who have defied the categories of their time and place — the kinds of people populating Figuring, which I wrote largely to explore such relationships — she adds:

Challenging these social norms is not new, nor are platonic partners the only dissidents. People who are feminists, queer, trans, of color, nonmonogamous, single, asexual, aromantic, celibate, or who live communally have been questioning these ideas for decades, if not centuries. All have offered counterpoints to what Eleanor Wilkinson, a professor at the University of Southampton, calls compulsory coupledom: the notion that a long-term monogamous romantic relationship is necessary for a normal, successful adulthood. This is a riff on the feminist writer Adrienne Rich’s influential concept of “compulsory heterosexuality” — the idea, enforced through social pressure and practical incentives, that the only normal and acceptable romantic relationship is between a man and a woman. Some of the first stories we hear as children instill compulsory coupledom, equating characters finding their “one true love” with living “happily ever after.”

[…]

It can be confusing to live in the gulf between the life you have and the life you believe you’re supposed to be living.

In the remainder of The Other Significant Others, Cohen relays the stories of people who have sliced through the confusion to build lives that serve them through tailor-made relationships that reward the deepest and truest parts of them, relationships that reimagine what it means to love and be loved, to see and be seen — relationships like those of Rachel Carson and Dorothy Freeman, Clara Schumann and Johannes Brahms, Ralph Waldo Emerson and Margaret Fuller.

Complement it with poet and philosopher David Whyte on love and resisting the tyranny of relationship labels, then revisit Coleridge on the paradox of friendship and romantic love.

BP

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