According to scholars of mysticism, these shared traits generally include a vision of unity in which all things, including the self, are subsumed (expressed in the phrase “All is one”); a sense of certainty about what one has perceived (“Knowledge has been revealed to me”); feelings of joy, blessedness, and satisfaction; a transcendence of the categories we rely on to organize the world, such as time and space or self and other; a sense that whatever has been apprehended is somehow sacred (Wordsworth: “Something far more deeply interfused” with meaning) and often paradoxical (so while the self may vanish, awareness abides). Last is the conviction that the experience is ineffable, even as thousands of words are expended in the attempt to communicate its power. (Guilty.)
Before my journeys, words and phrases such as these left me cold; they seemed utterly opaque, so much quasi-religious mumbo jumbo. Now they paint a recognizable reality. Likewise, certain mystical passages from literature that once seemed so overstated and abstract that I read them indulgently (if at all), now I can read as a subspecies of journalism. Here are three nineteenth-century examples, but you can find them in any century.
Ralph Waldo Emerson crossing a wintry New England commons in “Nature”:
Standing on the bare ground,—my head bathed by the blithe air, and uplifted into infinite space,—all mean egotism vanishes. I become a transparent eye-ball. I am nothing. I see all. The currents of the Universal Being circulate through me; I am part or particle of God.
Or Walt Whitman, in the early lines of the first (much briefer and more mystical) edition of Leaves of Grass:
Swiftly arose and spread around me the peace and joy and knowledge that pass all the art and argument of the earth;
And I know that the hand of God is the elderhand of my own,
And I know that the spirit of God is the eldest brother of my own,
And that all the men ever born are also my brothers . . . and the women my sisters and lovers,
And that a kelson* of the creation is love.
And here is Alfred, Lord Tennyson, describing in a letter the “waking trance” that descended upon him from time to time since his boyhood:
All at once, as it were out of the intensity of the consciousness of individuality, the individuality itself seemed to dissolve and fade into boundless being; and this was not a confused state, but the clearest of the clearest, the surest of the surest; utterly beyond words, where death was an almost laughable impossibility; the loss of personality (if so it were) seeming no extinction, but the only true life.
What had changed for me was that now I understood exactly what these writers were talking about: their own mystical experiences, however achieved, however interpreted. Formerly inert, their words now emitted a new ray of relation, or at least I was now in a position to receive it. Such emissions had always been present in our world, flowing through literature and religion, but like electromagnetic waves they couldn’t be understood without some kind of receiver. I had become such a one. A phrase like “boundless being,” which once I might have skated past as overly abstract and hyperbolic, now communicated something specific and even familiar. A door had opened for me onto a realm of human experience that for sixty years had been closed.*
But had I earned the right to go through that door, enter into that conversation? I don’t know about Emerson’s mystical experience (or Whitman’s or Tennyson’s), but mine owed to a chemical. Wasn’t that cheating? Perhaps not: it seems likely that all mental experiences are mediated by chemicals in the brain, even the most seemingly “transcendent.” How much should the genealogy of these chemicals matter? It turns out the very same molecules flow through the natural world and the human brain, linking us all together in a vast watershed of tryptamines. Are these exogenous molecules any less miraculous? (When they come from a mushroom or a plant or a toad!) It’s worth remembering that there are many cultures where the fact that the inspiration for visionary experiences comes from nature, is the gift of other creatures, renders them more meaningful, not less.
My own interpretation of what I experienced—my now officially verified mystical experience—remains a work in progress, still in search of the right words. But I have no problem using the word “spiritual” to describe elements of what I saw and felt, as long as it is not taken in a supernatural sense. For me, “spiritual” is a good name for some of the powerful mental phenomena that arise when the voice of the ego is muted or silenced. If nothing else, these journeys have shown me how that psychic construct—at once so familiar and on reflection so strange—stands between us and some striking new dimensions of experience, whether of the world outside us or of the mind within. The journeys have shown me what the Buddhists try to tell us but I have never really understood: that there is much more to consciousness than the ego, as we would see if it would just shut up. And that its dissolution (or transcendence) is nothing to fear; in fact, it is a prerequisite for making any spiritual progress.
But the ego, that inner neurotic who insists on running the mental show, is wily and doesn’t relinquish its power without a struggle. Deeming itself indispensable, it will battle against its diminishment, whether in advance or in the middle of the journey. I suspect that’s exactly what mine was up to all through the sleepless nights that preceded each of my trips, striving to convince me that I was risking everything, when really all I was putting at risk was its sovereignty.
When Huxley speaks of the mind’s “reducing valve”—the faculty that eliminates as much of the world from our conscious awareness as it lets in—he is talking about the ego. That stingy, vigilant security guard admits only the narrowest bandwidth of reality, “a measly trickle of the kind of consciousness which will help us to stay alive.” It’s really good at performing all those activities that natural selection values: getting ahead, getting liked and loved, getting fed, getting laid. Keeping us on task, it is a ferocious editor of anything that might distract us from the work at hand, whether that means regulating our access to memories and strong emotions from within or news of the world without.
What of the world it does admit it tends to objectify, for the ego wants to reserve the gifts of subjectivity to itself. That’s why it fails to see that there is a whole world of souls and spirits out there, by which I simply mean subjectivities other than our own. It was only when the voice of my ego was quieted by psilocybin that I was able to sense that the plants in my garden had a spirit too. (In the words of R. M. Bucke, a nineteenth-century Canadian psychiatrist and mystic, “I saw that the universe is not composed of dead matter, but is, on the contrary, a living Presence.”) “Ecology” and “coevolution” are scientific names for the same phenomena: every species a subject acting on other subjects. But when this concept acquires the flesh of feeling, becomes “more deeply interfused,” as it did during my first psilocybin journey, I’m happy to call it a spiritual experience. So too my various psychedelic mergings: with Bach’s cello suite, with my son, Isaac, with my grandfather Bob, all spirits directly apprehended and embraced, each time with a flood of feeling.
So perhaps spiritual experience is simply what happens in the space that opens up in the mind when “all mean egotism vanishes.” Wonders (and terrors) we’re ordinarily defended against flow into our awareness; the far ends of the sensory spectrum, which are normally invisible to us, our senses can suddenly admit. While the ego sleeps, the mind plays, proposing unexpected patterns of thought and new rays of relation. The gulf between self and world, that no-man’s-land which in ordinary hours the ego so vigilantly patrols, closes down, allowing us to feel less separate and more connected, “part and particle” of some larger entity. Whether we call that entity Nature, the Mind at Large, or God hardly matters. But it seems to be in the crucible of that merging that death loses some of its sting.
CHAPTER FIVE
THE NEUROSCIENCE
Your Brain on Psychedelics
WHAT JUST HAPPENED in my brain?
&nb
sp; A molecule had launched me on each of these trips, and I returned from my travels intensely curious to learn what the chemistry could tell me about consciousness and what that might reveal about the brain’s relationship to the mind. How do you get from the ingestion of a compound created by a fungus or a toad (or a human chemist) to a novel state of consciousness with the power to change one’s perspective on things, not just during the journey, but long after the molecule has left the body?
Actually, there were three different molecules in question—psilocin, LSD, and 5-MeO-DMT—but even a casual glance at their structures (and I say this as someone who earned a D in high school chemistry) indicates a resemblance. All three molecules are tryptamines. A tryptamine is a type of organic compound (an indole, to be exact) distinguished by the presence of two linked rings, one of them with six atoms and the other with five. Living nature is awash in tryptamines, which show up in plants, fungi, and animals, where they typically act as signaling molecules between cells. The most famous tryptamine in the human body is the neurotransmitter serotonin, the chemical name of which is 5-hydroxytryptamine. It is no coincidence that this molecule has a strong family resemblance with the psychedelic molecules.
Serotonin might be famous, as neurotransmitters go, yet much about it remains a mystery. For example, it binds with a dozen or so different receptors, and these are found not only across many parts of the brain but throughout the body, with a substantial representation in the digestive tract. Depending on the type of receptor in question and its location, serotonin is liable to make very different things happen—sometimes exciting a neuron to fire, other times inhibiting it. Think of it as a kind of word, the meaning or import of which can change radically depending on the context or even its placement in a sentence.
The group of tryptamines we call “the classical psychedelics” have a strong affinity with one particular type of serotonin receptor, called the 5-HT2A. These receptors are found in large numbers in the human cortex, the outermost, and evolutionarily most recent, layer of the brain. Basically, the psychedelics resemble serotonin closely enough that they can attach themselves to this receptor site in such a way as to activate it to do various things.
Curiously, LSD has an even stronger affinity with the 5-HT2A receptor—is “stickier”—than serotonin itself, making this an instance where the simulacrum is more convincing, chemically, than the original. This has led some scientists to speculate that the human body must produce some other, more bespoke chemical for the express purpose of activating the 5-HT2A receptor—perhaps an endogenous psychedelic that is released under certain circumstances, perhaps when dreaming. One candidate for that chemical is the psychedelic molecule DMT, which has been found in trace amounts in the pineal gland of rats.
The science of serotonin and LSD has been closely intertwined since the 1950s; in fact, it was the discovery that LSD affected consciousness at such infinitesimal doses that helped to advance the new field of neurochemistry in the 1950s, leading to the development of the SSRI antidepressants. But it wasn’t until 1998 that Franz Vollenweider, a Swiss researcher who is one of the pioneers of psychedelic neuroscience, demonstrated that psychedelics like LSD and psilocybin work on the human brain by binding with the 5-HT2A receptors. He did this by giving subjects a drug called ketanserin that blocks the receptor; when he then administered psilocybin, nothing happened.
Yet Vollenweider’s discovery, important as it was, is but a small step on the long (and winding) road from psychedelic chemistry to psychedelic consciousness. The 5-HT2A receptor might be the lock on the door to the mind that those three molecules unlock, but how did that chemical opening lead, ultimately, to what I felt and experienced? To the dissolution of my ego, for example, and the collapse of any distinction between subject and object? Or to the morphing in my mind’s eye of Mary into María Sabina? Put another way, what, if anything, can brain chemistry tell us about the “phenomenology” of the psychedelic experience?
All these questions concern the contents of consciousness, of course, which at least to this point has eluded the tools of neuroscience. By consciousness, I don’t mean simply “being conscious”—the basic sensory awareness creatures have of changes in their environment, which is easy to measure experimentally. In this limited sense, even plants are “conscious,” though it’s doubtful they possess full-blown consciousness. What neuroscientists and philosophers and psychologists mean by consciousness is the unmistakable sense we have that we are, or possess, a self that has experiences.
Sigmund Freud wrote that “there is nothing of which we are more certain than the feeling of our self, our own ego.” Yet it is difficult to be quite so certain that anyone else possesses consciousness, much less other creatures, because there is no outward physical evidence that consciousness as we experience it exists. The thing of which we are most certain is beyond the reach of our science, supposedly our surest way of knowing anything.
This dilemma has left ajar a door through which writers and philosophers have stepped. The classic thought experiment to determine whether another being is in possession of consciousness was proposed by Thomas Nagel, a philosopher, in a famous 1974 paper, “What Is It Like to Be a Bat?” He argued that if “there is something that it is like to be a bat”—if there is any subjective dimension to bat experience—then a bat possesses consciousness. He went on to suggest that this “what it is like” quality may not be reducible to material terms. Ever.
Whether or not Nagel’s right about that is the biggest argument going in the field of consciousness studies. The question at its heart is often referred to as “the hard problem” or the “explanatory gap”: How do you explain mind—the subjective quality of experience—in terms of meat, that is, in terms of the physical structures or chemistry of the brain? The question assumes, as most (but not all) scientists do, that consciousness is a product of brains and that it will eventually be explained as the epiphenomenon of material things like neurons and brain structures, chemicals and communications networks. That would certainly seem to be the most parsimonious hypothesis. Yet it is a long way from being proven, and a number of neuroscientists question whether it ever will be: whether something as elusive as subjective experience—what it feels like to be you—will ever yield to the reductions of science. These scientists and philosophers are sometimes called mysterians, which is not meant as a compliment. Some scientists have raised the possibility that consciousness may pervade the universe, suggesting we think of it the same way we do electromagnetism or gravity, as one of the fundamental building blocks of reality.
The idea that psychedelic drugs might shed some light on the problems of consciousness makes a certain sense. A psychedelic drug is powerful enough to disrupt the system we call normal waking consciousness in ways that may force some of its fundamental properties into view. True, anesthetics disrupt consciousness too, yet because such drugs shut it down, this kind of disturbance yields relatively little data. In contrast, someone on a psychedelic remains awake and able to report on what he or she is experiencing in real time. Nowadays, these subjective reports can be correlated with various measures of brain activity, using several different modes of imaging—tools unavailable to researchers during the first wave of psychedelic research in the 1950s and 1960s.
By deploying these technologies in combination with LSD and psilocybin, a handful of scientists working in both Europe and the United States are opening a new window onto consciousness, and what they are glimpsing through it promises to change our understanding of the links between our brains and our minds.
* * *
• • •
PERHAPS THE MOST AMBITIOUS neuroscientific expedition using psychedelics to map the terrain of human consciousness is taking place in a laboratory at the Centre for Psychiatry on the Hammersmith campus of Imperial College in West London. Recently completed, the campus consists of a futuristic but oddly depressing network of buildings, linked by glass-walled aerial walkw
ays and glass doors that slide open silently at the detection of the proper identification. It is here in the lab of David Nutt, a prominent English psychopharmacologist, that a team led by a thirtysomething neuroscientist named Robin Carhart-Harris has been working since 2009 to identify the “neural correlates,” or physical counterparts, of the psychedelic experience. By injecting volunteers with LSD and psilocybin and then using a variety of scanning technologies—including functional magnetic resonance imaging (fMRI) and magnetoencephalography (MEG)—to observe the changes in their brains, he and his team have given us our first glimpses of what something like ego dissolution, or a hallucination, actually looks like in the brain as it unfolds in the mind.
The fact that such an improbable and potentially controversial research project ever got off the ground owes to the convergence of three most unusual characters, and careers, in England in the year 2005: David Nutt, Robin Carhart-Harris, and Amanda Feilding, a.k.a. the Countess of Wemyss and March.
Robin Carhart-Harris’s path to David Nutt’s psychopharmacology lab was an eccentric one, having first passed through a graduate course in psychoanalysis. These days psychoanalysis is a theory few neuroscientists take seriously, regarding it less as a science than as a set of untestable beliefs. Carhart-Harris felt strongly otherwise. Steeped in the writings of Freud and Jung, he was fascinated by psychoanalytic theory while at the same time frustrated by its lack of scientific rigor, as well as by the limitations of its tools for exploring what it deemed most important about the mind: the unconscious.