The botany of desire: a plant's-eye view of the world (18 page)

One of the things certain drugs do to our perceptions is to distance or estrange the objects around us, aestheticizing the most commonplace things until they appear as ideal versions of themselves. Under the spell of cannabis “every object stands more clearly for all of its class,” as David Lenson writes in
On Drugs.
“A cup ‘looks like’ the Platonic Idea of a cup, a landscape looks like a landscape painting, a hamburger stands for all the trillions of hamburgers ever served, and so forth.” A psychoactive plant can open a door onto a world of archetypal forms, or so they can appear. Whether or not such a plant or fungus did this for Plato himself is of course impossible to ascertain, and somehow impious even to speculate on. But one could do worse, surely, searching for the spring of a metaphysics as visionary and strange as Plato’s.

• • •

The Platonic cup and the Coleridgean imagination are both “memes,” to use a term coined by the British zoologist Richard Dawkins in his 1976 book,
The Selfish Gene.
A meme is simply a unit of memorable cultural information. It can be as small as a tune or a metaphor, as big as a philosophy or religious concept. Hell is a meme; so are the Pythagorean theorem,
A Hard Day’s Night,
the wheel,
Hamlet,
pragmatism, harmony, “Where’s the beef?,” and of course the notion of the meme itself. Dawkins’s theory is that memes are to cultural evolution what genes are to biological evolution. (Unlike genes, however, memes have no physical basis.) Memes are a culture’s building blocks, passed down from brain to brain in a Darwinian process that leads, by trial and error, to cultural innovation and progress. The memes that prove themselves best adapted to their “environment”—that is, the ones that are most helpful for people to keep in their brains—are the ones most likely to survive and replicate and become widely regarded as good, true, or beautiful. Culture at any given moment is the “meme pool” in which we all swim—or rather, that swims through us.

Cultural change occurs whenever a new meme is introduced and catches on. It might be romanticism or double-entry bookkeeping, chaos theory or Pokémon. (Or the notion of memes itself, which seems to be catching on today.) So where in the world do new memes come from? Sometimes they spring full-blown from the brains of artists or scientists, advertising copywriters or teenagers. Often a process of mutation is involved in the creation of a new meme, in much the same way that mutations in the natural environment can lead to useful new genetic traits. Memes can mutate when they get combined in new ways, or when someone working with them makes a mistake—misreading or misinterpreting an old meme in such a way as to yield something new. For instance, besides being itself a new meme, Coleridge’s transforming imagination has turned out to be an excellent technology for generating other new memes.

When I read Dawkins, it occurred to me that his theory suggested a useful way to think about the effects of psychoactive plants on culture—the critical role they’ve played at various junctures in the evolution of religion and music (think of jazz or rock improvisation), of poetry, philosophy, and the visual arts. What if these plant toxins function as a kind of cultural mutagen, not unlike the effect of radiation on the genome? They are, after all, chemicals with the power to alter mental constructs—to propose new metaphors, new ways of looking at things, and, occasionally, whole new mental constructs. Anyone who uses them knows they also generate plenty of mental errors; most such mistakes are useless or worse, but a few inevitably turn out to be the germs of new insights and metaphors. (And the better part of Western literature, if literary theorist Harold Bloom’s idea of “creative misreading” is to be believed.) The molecules themselves don’t add anything new to the stock of memes resident in a human brain, no more than radiation adds new genes. But surely the shifts in perception and breaks in mental habit they provoke are among the methods, and models, we have of imaginatively transforming mental and cultural givens—for mutating our inherited memes.

• • •

At the risk of discrediting my own idea, I want to acknowledge that it owes a debt—how large I can’t say—to a psychoactive plant. The notion that drugs might function as cultural mutagens occurred to me while reading
The Selfish Gene
while high on marijuana, which may or may not be an advisable thing to do. But whatever its value, it’s at least a fresh idea (itself a kind of mutation of Dawkins’s meme idea), and I seriously doubt it would have occurred to me had I not smoked a little pot the evening I was reading Dawkins. (I wish I could say the same about the earlier speculation on Plato, but I’m afraid I was straight as a post for that one.)

I know, I said that I didn’t much like smoking pot. But research is research, and besides, my personal relationship to cannabis underwent a sea change while I was in Amsterdam. I’d heard so much about the improvements made to marijuana that I felt I had to give it another try, and I promptly discovered that this pot, at least, left me feeling neither stupid nor paranoid.

The nonstupid part can, I think, be accounted for by advances in cannabis breeding that make it possible to develop strains eliciting distinctly different mental effects. At the top end of the market this has led to a connoisseurship of cannabis—not just of its taste or aroma, but of the specific psychological texture of its high. Some strains (typically those with a higher proportion of
indica
genes) are narcotic in their effects, tending to stupefy. Others (often the ones with more
sativa
genes) leave the mind clear and fluent and the body unimpaired. Some of the growers I met spoke in terms of “white-collar” and “blue-collar” pot. The strains I found personally sympathetic were stimulating and, evidently, conducive to mental speculation.

As for the nonparanoid part, remember that I was in a country where one can smoke marijuana openly and without fear. The effect of the American drug war on the experience of smoking marijuana—a drug notoriously susceptible to the power of suggestion—cannot be overestimated. Writing in
The Atlantic Monthly
in 1966 about the intellectual “uses” of marijuana (now,
there’s
a topic that’s moved beyond the pale; these days one may speak of marijuana’s medicinal uses, perhaps, but
intellectual
?), Allen Ginsberg suggested that the negative feelings marijuana sometimes provokes, such as anxiety, fear, and paranoia, are “traceable to the effects on consciousness not of the narcotic but of the law.” Researchers speak of “set and setting” as crucial factors shaping one’s experience of any drug, and marijuana in particular almost unfailingly fulfills one’s expectation of it, for better and worse. Lenson calls it “the great yea-sayer, supporting whatever is going on anyway, and introducing little or nothing of its own.” In my experience, cannabis can’t reliably be used to change one’s mood, only to intensify it. Smoking in a comfortable coffee shop with a dozen other people doing the same thing, I had no reason to feel paranoid, which is probably why I didn’t.

Taking account of this phenomenon, Andrew Weil describes marijuana as an “active placebo.” He contends that cannabis does not itself create but merely triggers the mental state we identify as “being high.” The very same mental state, minus the “physiological noise” of the drug itself, can be triggered in other ways, such as meditation or breathing exercises. Weil believes it is an error of modern materialistic thinking to believe (as both drug users and drug researchers invariably do) that the “high” smokers experience is somehow a product of the plant itself (or THC), rather than a creation of the mind—prompted, perhaps, but
sui generis.

The truth of the matter is probably where it usually is, somewhere in the middle. Certainly the psychological experience of marijuana is far too varied, not only from person to person but from time to time, to be explained purely in terms of a chemical. At the same time, the chemistry of this
particular
plant surely has something specific to do with, say, the novel perceptions of Cézanne’s pictorial space that Ginsberg describes in his
Atlantic
essay, the religious insights brought back by shamans, or even my own vagrant speculations on mutating memes. Opium would probably induce different kinds of thoughts in the same brains. We assume that there is some sort of cause-and-effect relationship between molecule and mind, but what it is no one really knows.

As the sorcerers, shamans, and alchemists who used them understood, psychoactive plants stand on the threshold of matter and spirit, at the point where simple distinctions between the two no longer hold. Consciousness is what we’re talking about here, of course, and consciousness is precisely the frontier where our materialistic understanding of the brain stops—at least for the time being, but possibly forever. What’s interesting about a plant like marijuana is that it takes us right up to that frontier and may have something to teach us about what lies on the other side. We tend to smile indulgently at poets like Allen Ginsberg for believing that cannabis is a useful tool for exploring consciousness. But it turns out they may be right.

• • •

In the mid-1960s, an Israeli neuroscientist named Raphael Mechoulam identified the chemical compound responsible for the psychoactive effects of marijuana: delta-9-tetrahydrocannabinol, or THC, a molecule with a structure unlike any found in nature before or since. For years Mechoulam had been intrigued by the ancient history of cannabis as a medicine (a panacea in many cultures until its prohibition in the 1930s, it has been used to treat pain, convulsions, nausea, glaucoma, neuralgia, asthma, cramps, migraine, insomnia, and depression) and decided it might be worthwhile to isolate the plant’s active ingredient. But it was the popularity of marijuana as a recreational drug in the sixties, and the attendant official worries, that freed up the resources to underwrite this kind of work—and a great deal of other cannabinoid research that, taken together, has yielded more knowledge about the workings of the human brain than anyone could have guessed.

In 1988 Allyn Howlett, a researcher at the St. Louis University Medical School, discovered a specific receptor for THC in the brain—a type of nerve cell that THC binds to like a molecular key in a lock, causing it to activate. Receptor cells form part of a neuronal network; the brain systems involving dopamine, serotonin, and the endorphins are three such networks. When a cell in a network is activated by its chemical key, it responds by doing a variety of things: sending a chemical signal to other cells, switching a gene on or off, or becoming more or less active. Depending on the network involved, this process can trigger cognitive, behavioral, or physiological changes. Howlett’s discovery pointed to the existence of a new network in the brain.

The cannabinoid receptors Howlett found showed up in vast numbers all over the brain (as well as in the immune and reproductive systems), though they were clustered in regions responsible for the mental processes that marijuana is known to alter: the cerebral cortex (the locus of higher-order thought), the hippocampus (memory), the basal ganglia (movement), and the amygdala (emotions). Curiously, the one neurological address where cannabinoid receptors
didn’t
show up was in the brain stem, which regulates involuntary functions such as circulation and respiration. This might explain the remarkably low toxicity of cannabis and the fact that no one is known to have ever died from an overdose.

On the assumption that the human brain would not have evolved a special structure for the express purpose of getting itself high on marijuana, researchers hypothesized that the brain must manufacture its own THC-like chemical for some as-yet-unknown purpose. (The scientific paradigm at work here was the endorphin system, which is tripped by opiates from plants as well as endorphins produced in the brain.) In 1992, some thirty years after his discovery of THC, Raphael Mechoulam (working with a collaborator, William Devane) found it: the brain’s own endogenous cannabinoid. He named it “anandamide,” from the Sanskrit word for “inner bliss.”

Someday soon Mechoulam and Howlett will almost surely receive the Nobel Prize, for their discoveries opened a new branch of neuroscience that promises to revolutionize our understanding of the brain and lead to a whole new class of drugs. Following on their work, neuroscientists are now busy trying to figure out exactly how the cannabinoid network works—and why we should have one in the first place.

I put that question to Mechoulam and Howlett and several of their colleagues in cannabinoid research, and their answers, while speculative, are richly suggestive. The cannabinoid network is unusually complex and varied in its functions, I learned, in part because it seems to modulate the action of other neurotransmitters, such as serotonin, dopamine, and the endorphins. When I asked Howlett what the purpose of such a network might be, she began her answer by listing some of the various direct and indirect effects of cannabinoids: pain relief, loss of short-term memory, sedation, and mild cognitive impairment.

“All of which is
exactly
what Adam and Eve would want after being thrown out of Eden. You couldn’t design a more perfect drug for getting Eve through the pain of childbirth or helping Adam endure a life of physical toil.” She noted that cannabinoid receptors had been found in the uterus, of all places, and speculated that anandamide may not only dull the pain of childbirth but help women forget it later. (The sensation of pain is, curiously, one of the hardest to summon from memory.) Howlett speculated that the human cannabinoid system evolved to help us endure (and selectively forget) the routine slings and arrows of life “so that we can get up in the morning and do it all over again.” It is the brain’s own drug for coping with the human condition.

For his part, Raphael Mechoulam believes that the cannabinoid network is involved in regulating several different biological processes, including pain management, memory formation, appetite, the coordination of movement, and, perhaps most intriguingly, emotion. “We know next to nothing about the biochemistry of emotion,” Mechoulam points out, but he thinks we’ll eventually discover that cannabinoids are involved in the process by which the brain “translates objective reality into subjective emotions.”