“If you get into any trouble, try concentrating on your breath. Sometimes the breath is all you have.”

Brian looked concerned, though he also looked weirdly elongated, ­so it was hard to tell what was actually happening. I was on drugs, you see, and not just any drug. Thirty minutes earlier I had gulped back a cupful of ayahuasca, a plant-based hallucinogen that William Burroughs—no slouch when it came to chemical experimentation—once described as the most powerful he had ever experienced. This was my third trip in six days, and I’d taken half again as much as anyone else in the group. Now nobody would look me in the eye.

This was several years ago, during a perspective-altering ten-day workshop in South America. Today, most armchair adventurers will have heard of ayahuasca, which first escaped from the Amazon jungle in the 1930s and has recently leapt from underground curiosity to zeitgeist sensation. Following in the footsteps of celebrities such as Sting and Oliver Stone, every year thousands of people fly to countries like Peru, Brazil and Ecuador, where ayahuasca can be sampled in the company of professional shamans—some respectable, some not. Having had their fill of physical travel, Westerners now want to sail right out of their minds.

Others quaff more locally. British Columbia’s Pender Island, Toronto’s beaches and Montreal’s suburbs host gatherings of the curious (supervised by imported boutique shamans) and congregations of the two fastest-growing syncretic churches that use ayahuasca as a sacrament: the Santo Daime and the União do Vegetal. Both churches—part animist, part Christian—have outposts across Latin America, Europe and North America; none other than Jeffrey Bronfman, third-generation member of the famous Montreal whisky family, heads the Santa Fe chapter of the União do Vegetal. Ayahuasca’s precise legal status in the US and Canada is ambiguous. But, if you’re determined, getting your hands on the stuff isn’t hard.

Ayahuasca owes its popularity to its alleged psycho-spiritual benefits. As one retreat centre’s website puts it: “the equivalent of ten years of therapy in one night, ayahuasca can promote healing and transformation in areas of relationships, self esteem and creative potential, to name a few.” Claims like this (circulated in online forums and, increasingly, in feature-length documentaries and mainstream news outlets) are part of a larger renaissance in the world of psychedelic-drug research; clinical trials are now exploring the potential of drugs like LSD and ecstasy to treat everything from post-traumatic stress disorder to addiction to cluster headaches. Yet of all these drugs, it’s ayahuasca that has generated the most interest outside the world of test subjects and clinicians. Call it hippie Prozac: the must-have miracle cure for the new New Age.

This is startling enough. But ayahuasca may be at the nexus of an even deeper revolution, one that explores how indigenous forms of knowledge—long discounted in the West—could contribute to our understanding of consciousness and reality. That’s because, according to devotees, ayahuasca is a direct channel to nature’s interior aspect, to a whole pantheon of extrasensory intelligences: other human psyches, alien beings, the spirits of plants and animals. To update Aldous Huxley’s famous quip about mescaline, ayahusaca blows the doors of perception right off their hinges. It disables what Huxley called the “cerebral reducing valve” and plunges the stunned psychonaut into a seething ecology of other minds.

Of course, for every investigator who holds this rather unscientific point of view, there is another who points out that such testimonials are, after all, generated by people on drugs. Although sympathetic to some of the therapeutic claims made on behalf of ayahuasca, I wasn’t sure the plant mixture could support the West’s collective expectation of spiritual-satori-slash-psychological-analysis. I was even more skeptical about the metaphysical assertions. We don’t believe dreams are “real”—why should an ayahuasca vision be any different? Nevertheless, the rich history of ayahuasca usage has undeniable authority; in the end, the only way to really answer these questions was to launch into the psychedelic troposphere and find out for myself.

THE NAME OF MY DESTINATION, as well as its location, is secret. All I can say is that it was a family-run compound at the edge of a dark forest. Though ayahuasca is legal in this tropical country, there are politics surrounding its use, and the owner of the compound—I’ll call him Alejandro—prefers to keep a low profile. I learned about the workshop through word of mouth, though similar opportunities can be found online. Where once ayahuasca-seekers had to ford piranha-infested rivers and barter with locals, now, for a few thousand dollars, tour operators will pick you up in air-conditioned coaches, cook you delicious vegetarian meals and ensure your linen is changed daily.

My host was waiting in the parking lot when I stepped out of the taxi. Alejandro, brown-eyed and courteous, shook my hand, and in the fading light ushered me inside. Alejandro began studying with traditional Amazonian shamans—ayahuasqueros—in the seventies. The men showed him how the plant mixture can be used for healing and revelation, and he began to think that ayahuasca might also facilitate a kind of secular enlightenment.

Two hours after I’d arrived, our group gathered in a large room with hardwood walls. We were invited to explain why we had come. There were about a dozen of us, and perhaps a third were there for therapeutic reasons: therapists looking to incorporate ayahuasca into their practices, or patients seeking treatment. One forty-year-old woman had been abused as a child and wanted to make peace with her history. Another, a Finnish professor, sought insight into his embittered relationship with his wife. There was even an RCMP officer on a private mission to bring law and order to his own mind.

The rest were an eclectic collection of anthropologists, research psychologists and students. This group—the deep-cave spelunkers of consciousness—had more profound goals. They believed that ayahuasca didn’t simply lift users to new levels of perception, but also brought them into direct contact with a spirit realm inhabited by nonhuman intelligences. They dubbed it “DMT-space,” after one of the drug’s compounds. Most ayahuasca brews are made from two ingredients. The first is a leafy plant called Psychotria viridis, which contains the powerful psychoactive alkaloid dimethyltryptamine, or DMT. If eaten alone, the digestive system neutralizes DMT’s effect. But, when it’s combined with the Banisteriopsis caapi vine—which inhibits the enzymes that suppress DMT—the real trip begins. While other psychedelics might hint at this spirit realm, some claim that ayahuasca is unique in teleporting you directly inside it, providing multi-sensory initiations into landscapes of great beauty and complexity.

I felt conspicuously skeptical in my corner of the room. “Journalisto de consciousness,” I joked, pointing to my head, when it was my turn to explain my intent. I said that I had just finished writing a book on the waking and sleeping mind, and believed that what happened on ayahuasca could be explained by the neurological mechanics of Rapid Eye Movement sleep, recursive sensory feedback loops and the human brain’s amazing ability to build immersive models of the world during dreams. “With the careful application of reason,” I wrapped up, “we can shed some much-needed light on the phenomenology of this curious plant mixture.”

The room, I noticed, was mostly empty. Somehow I had not heard the dinner bell.

That night I had a dream. I stood in a dark room next to a flickering fire. Someone handed me a cup of muddy liquid. As I brought it to my lips I heard Alejandro repeat what he told us that day: “You will look different once you leave here. You will not recognize yourself in the mirror.” I woke with a start. I could hear sounds coming from the jungle outside, soft trills and staccatos. My belly was tight with expectation.

THE NEXT DAY we each signed a waiver, assuming all risks. Ayahuasca is in no way a recreational drug. Though I had never heard of it killing anyone, compounds in the plants react very badly with common antidepressants. It can also cause severe headaches and even cardiac arrhythmia if combined with beer, cheese, wine, coffee and a number of other foods. Two weeks before arriving, we had begun a salt- and sugar-free diet, and for the duration of our stay we ate no meat or spicy foods.

It was winter in South America; the sun set early. At 8:30 pm we met in the main room under soft yellow lamps. Along each wall was a row of evenly spaced mattresses, which fanned out toward the centre of the room like the spokes of a square wheel. Next to each mattress sat a plastic bucket. On a shelf at the front was a clear bottle filled with dark fluid.

We sat in a circle and discussed our intentions: who we were grateful to, what we hoped to accomplish. I felt reassured. One of the abiding lessons of sixties psychedelic experimentation—and something indigenous shamans have long appreciated—is that both your mindset and environment matter enormously when you ingest plant medicines. Positive outlook, controlled surroundings, supportive company: good trip. Terrified outlook, chaotic surroundings, hostile strangers: bad trip. The former is a recipe for profound insight retrieval. The latter is a recipe for ending up naked and raving in the back of a paddy wagon after a Grateful Dead concert.

Alejandro handed out plastic glasses and we gathered round to receive our portions. Everyone would start with around eighty millilitres, though we had the option of taking boosters later on in the night. I reached out my cup and watched as Alejandro filled it with purple liquid.

We raised our glasses—“Salud!”—and gulped the drug back, Alejandro included. Disgusting, but not as bad as I had expected; it tasted like rancid grapefruit juice. Each of us chose a mattress and settled down, sitting cross-legged to stave off the nausea. Vomiting and diarrhea—la purga, they called it—was part of the experience, and according to some a necessary catalyst. But first the drug had to snake its way down into our systems, a process that could take up to an hour. I looked around the dimly-lit room. Hunched, people looked as though they were meditating. I closed my eyes and waited.

After about forty minutes, Alejandro picked up a rattle and sang a short, haunting icaro—a shamanic chant. In Singing to the Plants, scholar Steve Beyer calls icaro “the language of the plant.” Natural spirits give the shaman these icaros, which become the voice of the shaman in ceremony.

Alejandro, defiantly modern, put down the rattle and selected an icaros playlist from his laptop. I felt something shift in the room. The jungle sounds were louder. I heard a faraway hiss. One indigenous group calls ayahuasca “the airplane” because the trip arrives from high overhead with a low buzzing. When I opened my eyes the room had a fuzzy, vibrating quality. The halo of colour around each lamp deepened. I realized I was holding my breath. As I exhaled I felt something pour into me, an upwelling of alertness. It felt vaguely sexual, as if I were being seduced from the inside. I knew my mouth was hanging open but I couldn’t close it. My body was heavy all over, my lips thick. There were no ideas and no visions, only a powerful physicality, a high not unlike what I’d experienced from ecstasy.

With his white robe and screen-lit features, Alejandro looked iconic, the eternally-presiding cosmic DJ. From the speakers, a low drumming began to build, a woman’s voice crying eerily overtop. Suddenly everyone was standing up. I was unsure how much time had passed, but saw that the group had clustered around Alejandro to receive boosters. I staggered across the room with my glass extended and shot back another forty millilitres of liquid. It was a mistake. The rush that followed flattened me to my mattress.

Someone was on the floor by my feet. I squinted and recognized Susan, a retired schoolteacher. A composed, white-haired woman in her sixties, she was now moaning and squirming like a lizard, hands pressed to her pelvis and breasts. Another woman, Masha, leapt up and began a slithery Medusa dance, her voice raised to a high-pitched keening, accompanied now by Alejandro’s furious bongo-playing, which echoed off the walls with percussive force.

As if on cue, the Estonian psychologist, Alar, vomited into his bucket, setting off a domino effect of throaty purges around the room. Susan began humping the air. The Mountie groaned and raised his arm, as if to ward off an assailant. Someone else started barking. The Finnish professor—also in his sixties—came spinning in from the sidelines, hair shocked upwards in an Elvis-style pompadour, and pranced around Susan’s undulating body.

It was all too much. I struggled to my feet, teetered, and fell sideways over a chair. On my hands and knees I managed to crawl to the bathroom, where I was noisily ill. I spent the next two hours slumped next to the toilet, disappointed by my lack of visions, but also giggling at the whole bizarre circus. Behavioural reality, at least, was beginning to shift.

IN THE MORNING, the group reported generally satisfactory experiences. As is customary with ayahuasca, many people saw snakes when they closed their eyes, and Masha matter-of-factly described transforming into a reptile.

The snake motif puzzles consciousness theorists. How is it possible that almost everyone seems to see serpents, regardless of cultural background or personal expectations? There are other recurring elements, too: jaguars, ancient cities, ornamentation. The first written description of an ayahuasca trip comes from an Ecuadorian geographer named Manuel Villavicencio, who, in 1858, perceived “the most gorgeous views, great cities, lofty towers, beautiful parks, and other extremely attractive objects.” Believers use accounts like this as proof of a coherent alternative reality.

The late psychedelic trickster and author Terence McKenna popularized what is perhaps the strangest meme associated with DMT: under its influence, people come into contact with alien beings he called “machine elves,” or more colourfully, “self-dribbling bejewelled basketballs.” By turns courteous, cruel or indifferent, these enigmatic characters beep and trill and execute various mind-boggling stunts in the drinker’s DMT space. They are not to be confused with the plant spirits, who have their own particular proclivities and personalities.

Are these entities ambassadors from other levels of reality, as shamans believe? Or are they dramatizations of our own interior processes, as is the standard Western judgment? James Kent makes a strong case for the latter. The battle-hardened psychonaut, editor of DoseNation.com and author of Psychedelic Information Theory argues that hallucinogens interfere with receptors in the visual cortex, provoking a cascade of phosphenes we then anthropomorphize into grinning human features. Psychologists call this “gap-filling.”

This, of course, is the rationalist perspective. But some Westerners closest to indigenous societies—the actual anthropologists who live and drink with them—have come to disagree with that view. Steve Beyer lists in his book at least four anthropologists who, in their own ways, argue that the spirit world is ontologically real. Even the respected Israeli cognitive psychologist Benny Shanon, who describes his own ayahuasca experiences in The Antipodes of the Mind, grudgingly admits his visions may “reflect patterns exhibited on another, extra-human realm.”

Beyer himself takes a slightly different tack. Yes, he says, after many encounters he has come to accept the spirit world as real. But reality itself cannot be confined to a single point or plane. We may actually live, he said recently, on a “spectrum of reality.”

AFTER A DAY OF REST, I took a second trip across the spectrum of reality. It unfolded in much the same manner, beginning with awe, a great sense of mystery, something stirring in the room. I felt as if I were strapped inside an enormous vibrating didgeridoo. Behind my closed lids, purple blobs of colour receded into a distant grid. When I opened my eyes, everything was bordered by concentric Aztec squares, recursive and symmetrical. They were similar to the geometric distortions I had perceived on magic mushrooms and LSD. Occasionally I thought I saw figures and shapes coalesce on the periphery of my gaze, straining toward some kind of incarnation. But no machine elves came.

And yet, near the end of my trip, as the music tapered into more reflective hymns, something did happen: I had a wave of insights about my relationship, my family, my friends. I saw my actions as if from far above and watched as they rippled out into other people’s lives. There was nothing recriminatory about the experience—rather, it had a gentle, matter-of-fact character that slipped through my usual psychological defenses. It was easy to see how this could be therapeutic. The supercharged circumstances of the ceremony only reinforced my realizations; it was like having my thoughts underlined with a psychic highlighter.

The next day, as before, we described our experiences. Brian had catapulted to a place where “language and syntax don’t exist.” Later, coming down, he had a vision of a tree heavy with fruit. Each piece, he knew, represented a different relationship in his life—his mother, his girlfriend, his peers. As he pulled each fruit from its stem he looked past the flesh to the pit and saw, systematically, how to manage each relationship with more love and compassion. He was grateful, he said, to the plant teacher.

We began to discuss the origin of our visions. I suggested the most prudent explanation lay with the brain’s chemistry and the intersection of the drug’s two active agents. One plant boosts the amount of serotonin in the body, creating a hyper-alert ecstatic feeling, while the other boosts the amount of DMT, a naturally-occurring brain chemical thought to play a role in REM sleep. “Thus,” I said, “the serotonin circle overlaps with the DMT circle, and we sit in the middle, submerged in a waking dream.”

Ayahuasca is a catalyst for therapeutic insight, I continued, because “normal” thinking—all our dependable assumptions about the world and the self—cannot proceed. We’re forced to make new connections. What’s more, this happens within a larger climate of what psychiatrist Daniel X. Freedman called, in a classic 1968 paper on LSD, “portentousness,” or “the capacity of the mind to see more than it can tell, to experience more than it can explicate, to believe in and be impressed with more than it can rationally justify.”

“Psychotropics like ayahuasca,” I concluded, “allow us to both see the world anew, and overlay that world with an abiding sense of its irreducible complexity and mystery. Isn’t that enough?”

Michael, a well-known anthropologist and author, shared his own theory. Psychedelics, he explained, acted as “psycho-integrators,” linking up three evolutionary layers of the brain: the ancient reptilian brain stem, the middle-aged mammalian limbic system and the relatively modern frontal cortex. Ayahuasca, he told the group, rerouted habitual ways of thinking down through the primitive brain stem. “That’s why you can’t put so many of these experiences into words,” he said. “The reptile brain stem can’t make words. It’s pre-verbal.”

Matt from San Francisco was shaking his head. “You guys have no idea. You can talk about the brain all you want, but it says nothing about the experience and the reality of these encounters.”

Brian joined him. “Ayahuasca shows that what we think of as boundaries are really borders. This reality here,” he said, gesturing around the room, “is just a container for one kind of order. There are others. The truth of this isn’t something you can ‘figure out.’ It works on you from the inside, until you arrive at a different way of seeing. It only seems strange because we don’t understand it.”

I wanted to believe them, of course. Who wouldn’t? The alternative was imprisonment in my own head—the crisis of the lab technician, cut off from a nourishing world of spirit and connection. I envied people like Brian and Matt. They were smart and informed, yet they also believed. Perhaps they had the best of science and spirituality. Could I arrive at this place too, without becoming some disorderly mystic? I didn’t know, but after our discussion I was hell-bent on finding out.

AT THE BEGINNING of the third trip, I asked for 160 millilitres—double what I’d started with the first time. Alejandro, hesitating, said I would need a straightjacket if I wasn’t careful. I laughed and told him to pour my rations. He obliged, shaking his head.

Within half an hour I knew I was in trouble. Shadows cast by a flickering candle crowded in on me. When I closed my eyes, the shadows were still there, moving closer, bent into impossible angles. My last coherent emotion was shame. “I am a fool,” I said out loud.

Brian told me to concentrate on my breath, but it was too late: I had no breath, or hands for that matter—both arms had dissolved into green and yellow pixels. A moving front of particulate matter surged up my neck and into my throat, my whole yapping head apparatus suddenly flipped inside out. Every category immediately became meaningless. There was no “up” or “down,” no “real” or “hallucinated.” My thoughts were no different from physical objects. Everything—mind and matter—was composed of the same omnipresent material, pressing and twisting against me.

Was I breathing? I couldn’t tell—that idea was inconsequential, too. So was the concept of my death, which felt imminent. I tried to summon an image of my mother, but her disappointment had too many dimensions. I began to laugh, hunched on my mattress, hands gripping my head as I peeled over sideways like a Picasso abstract. I recognized, even in my terror, the situation’s dark comedy, the spectacle of my rational mind scurrying through the maelstrom with its pathetic building materials. I wanted to ask for help but couldn’t formulate the words.

Finally, after what seemed like a very long time, it passed. My forehead was clammy with sweat. Alejandro squatted by my side and asked if I was all right. I was, but also not. I lay on my mattress, feeling very alone, as if I had been to the dark sub-basement of the mind, where all the big, clunky turbines operated. There was no intelligence there, just the hardware, the machinery, constructing a seamless hidden world, overtop of which glided our everyday minds, confident and oblivious. Once again, I had not seen the nurturing plant spirits. I felt forsaken.

I wasn’t alone. “This is my fiftieth ayahuasca session,” said Susan the next day, her voice cracking. “I can’t remember the last time I had a visit from the Mother. I keep drinking, but nothing helps.” She looked around the room for help, but no one knew what to say. This wasn’t in the brochure.

I was afraid to take ayahuasca again, but later that night I forced myself to drink. The brew tasted much worse now, foul beyond belief. Two hours in, something unexpected happened. Watching the others—Brian staring calmly into the room, Susan mumbling softly to herself, the professor on his back, turning his hands in front of his face—I felt a very present and immediate tenderness. I closed my eyes. I could sense them all, moving in their private worlds, but also brushing up against my own. It was an odd feeling. My skin tingled as if each person were right up against me, but when I opened my eyes everyone was still on their mattresses. Was this the feeling of unity they were talking about? Brian told me that in a session he had done the previous year, he “crashed” into the mind of a woman sitting next to him. Both of them could sense the other’s freaked-out thoughts, an event the two later discussed, even though, he said, “we didn’t need to.”

My heightened sensitivity persisted through the night. Toward dawn, after everyone else had gone to sleep, I went outside and stood at the edge of the forest next to the compound. Everything was very still, yet the trees had an uncommon expressiveness. They reached upward to the brightening sky, but remained protective of their many shadows. I strained my ears, trying to pick up the solemn vibes of some fibrous tree spirit. I wrapped my arms around what looked like a sympathetic araucaria. It had happened: tree-hugger. I whispered endearments into the smooth bark.

The following day we said our goodbyes, and I returned home feeling unusually calm and lucid. It was a sensation similar to what I had experienced after a meditation retreat, a state of composure I have heard described by other long-term consumers of psychedelics, the ones who hadn’t come unhinged. Many forms of intense introspection, it seems, lead to clearings. So what had become clear to me? What kind of knowledge do psychedelics like ayahuasca impart?

THE POET DALE PENDELL has a term for the practice of sacred plant use: “the poison path.” The poison’s first victim is certainty; it weakens pre-existing worldviews and self-conceits. This can be terrifying, and liberating, and desolating, sometimes in that order. Especially if—as in my case—the plant continues to confound our hopes and expectations. In the end, the psychedelic seeker must depend on her own capacity to discriminate, to artfully integrate the lessons and visions—and, sometimes, lack of visions—into her life. If you have a good shaman you don’t have to do this alone. Part of the shaman’s craft is to work creatively with plant energies as they interface with our own. Though the shaman keeps the energy moving, so much depends on individual context. It is not a case of taking your medicine and being handed the truth. This may be what Westerners seek, but it is not what the shaman—or the medicine—offers.

Ayahuasca, however, does leave one certainty intact: our kinship with nature. Like other psychedelic thinkers, Alejandro believes that ayahuasca and other organic psychotropics act as nature’s corrective. They bring us back into alignment with ecological reality, with the tangled web of biological dependencies—human and extra-human—through which we move so carelessly. This is why, Alejandro told me, so many of those who try ayahuasca end up changing careers, becoming environmental lawyers or field biologists or organic farmers. They see with new clarity how abusing the planet—dumping pollution into the air and sea, eliminating entire species, hacking down jungles—is a kind of self-harm. The reverberations of this truth depend on how far along the spectrum of reality you are willing to go. For some, the fact of ecological connection is enough. Others go further.

Ayahuasca has been called “one of the most sophisticated and complex drug-delivery systems in existence.” One oft-mentioned mystery is how indigenous people knew to combine the elements of the drug, since they grow in separate ecological niches and are just two of over eighty thousand plant species that exist in the Amazon basin. Shamans say the plants told them. When you delve into the anthropological literature on indigenous views of nature, from the Cherokee to the Iroquois to the Shipibo, shamans say the same thing: via visions and dreams and waking intuitions, the plants tell them things, things they have no way of knowing otherwise. They are not speaking metaphorically. Rather, they are literally saying that all things are alive and talking to one another. It may not even be necessary to ingest a plant to partake in this dialogue. The simple act of walking through the woods, if done with the correct attitude and sensitivity, can be a learning experience. It is a matter of bringing to the forest the same empathy and openness we should bring to human society. In this sense, all of nature is very subtly psychoactive.

This kind of knowledge relies heavily on one’s internal state, which drives hardcore skeptics batty—accessing it depends in part on one’s openness to the situation. But that’s the mind for you. You can’t escape it or even properly assess its influence. It’s like the eye trying to see itself. Amateur psychonauts, too, would do well to consider this: no matter how many perspective-expanding substances you take, no matter how many insights you generate and genuine multi-dimensional perceptions you entertain, you will never expand past the incontrovertible fact of your own subjective filter. This may be the central insight of psychedelic philosophy.

So where does all this leave the shaman’s anomalous spirits? I didn’t encounter any elves or vegetal entities. But ayahuasca did leave me with the sense that the world is humming with organizing patterns that affect our minds in ways we’ve hardly begun to appreciate. Our psychology and neurobiology, of course, shape how we receive and interpret these patterns. But my feeling is that we do not create them any more than we create the songbird’s call or the movement of wind in the trees. What seems like nature mysticism now could be the next generation’s environmental science: both an intimation of the biosphere’s complex information exchange and a glimpse into nature’s vast interiority, intelligence—maybe even agency.

These are grand claims, especially given the case I’ve just made for the mind’s fundamental indeterminacy. I recognize my own existential neediness; I’m not unbiased. No one is. The mind’s shaping power, however, is actually good news. It suggests that, when it comes to some aspects of consciousness and reality, you get to choose the kind of world you want to live in. I know what it’s like to follow a mechanistic outlook through to its logical conclusion: it’s lonely and scary and it made me want to roll up in a fetal position next to a bucket of my own barf. But in my tiny moment of connectivity with all things—my immersion in a shared world of living presence—I felt a consolation and a wonder I will not forget.