Before Timothy Leary came along, psychedelic drugs were respectable. The American public’s introduction to these substances was gradual, considered, and enthusiastic. Psilocybin appeared in an article, “Seeking the Magic Mushroom,” in a 1957 issue of Life magazine. The author of this first-person account of consuming mind-altering fungi at a traditional ritual in a remote Mexican village, R. Gordon Wasson, was a banker, a vice president at J.P. Morgan. The founder and editor in chief of Time-Life, Henry Robinson Luce, took LSD with his wife under a doctor’s supervision, and he liked to see his magazines cover the possible therapeutic uses of psychedelics. Perhaps most famously, Cary Grant underwent more than 60 sessions of LSD-facilitated psychotherapy in the late 1950s, telling Good Housekeeping that the treatment made him less lonely and “a happy man.” This wasn’t a Hollywood star’s foray into the counterculture, but part of an experimental protocol used by a group of Los Angeles psychiatrists who were convinced they had found a tool that could make talk therapy transformative. And they had the science—or at least the beginnings of it—to back up their claims.

Then came Leary and his Harvard Psilocybin Project. In his new book, How to Change Your Mind: What the New Science of Psychedelics Teaches Us About Consciousness, Dying, Addiction, Depression, and Transcendence, Michael Pollan recounts how nascent but promising research into the therapeutic uses of psychedelic drugs in the 1950s and early 1960s went off the rails. Leary, with Richard Alpert (who would later rename himself Ram Dass), conducted research in a methodologically haphazard and messianic manner, eventually alienating the university’s administration, who fired them. Leary then went on to become a guru (his term) for the hippie movement, urging America’s youth to “turn on, tune in, and drop out.” LSD came to be associated with the anti-war movement, free love, and a general rejection of Middle American mores, and the authorities no longer looked kindly upon it. By 1970, with the Controlled Substances Act, LSD, psilocybin, peyote, DMT, and mescaline were classified as Schedule I drugs—defined as substances with a high potential for abuse, with no currently accepted medical value in the U.S., and unsafe to use even under medical supervision. For four decades, psychedelics were associated with burnt-out cases shambling around college towns like Berkeley and Cambridge, chromosome damage, and the suicide of the daughter of TV personality Art Linkletter.

How to Change Your Mind is not your average pro-psychedelic book, of which there are multitudes.

Pollan is far from the first person to point out that none of the above characterizations are truthful representations of the most familiar psychedelic drugs. As Purdue’s David E. Nichols wrote in 2016 for the peer-reviewed medical journal Pharmacological Reviews, these drugs are “generally considered physiologically safe and do not lead to dependence or addiction.” There have been no known cases of overdose from LSD, psilocybin, or mescaline. The chromosome scare story turned out to be bogus, Diane Linkletter had a history of depression pre-existing her drug use, and while it’s probably a bad idea for any mentally disturbed person to take a powerful psychoactive drug recreationally, there’s no evidence that psychedelics cause mental illness in otherwise healthy people. To the contrary: After 40 years in the wilderness, psychedelics are once more the subject of serious scientific study, with early results suggesting that the drugs, when used under a therapist’s supervision, can help patients suffering from anxiety, depression, post-traumatic stress disorder, obsessive-compulsive disorder, and both alcohol and nicotine addiction.

How to Change Your Mind is not your average pro-psychedelic book, of which there are multitudes. The recently-published Trip by Tao Lin, a player on the small-time literary hipster scene, is more typical. It resembles the sort of predictably eccentric title people used to buy in head shops or order off the classified ads in High Times, albeit updated for the internet age. No doubt it’s difficult to make a case for psychedelic drugs without sounding like a kook. One of the defining qualities of a powerful trip is the sense that mere words can’t do justice to it. By the end of Trip, Lin, who during a period of weaning himself off of various pharmaceuticals became a devotee of the late psilocybin advocate Terence McKenna, has become both a bit happier and a bit daffier, in a decidedly hippie-ish mode. He expounds on the dubious goddess-worship theories of Riane Eisler and Marija Gimbutas, and maintains that daily doses of turmeric have enabled him to crack his knuckles for the first time. He believes that by consuming only plant-based psychedelics (which he doesn’t even consider to be drugs), he has established communication with “nature.” Just how much of this quirkiness can be attributed to using the substances isn’t clear; Lin reports, for example, that even before he began using psychedelics he suffered from a lifelong obsession with the belief that his teeth and tongue were too big for his mouth, signs of what he now regards as “degenerate” jaw formation caused by modern diets.

On its surface, Ayelet Waldman’s A Really Good Day, published in 2017, is the polar opposite of Trip. A middle-class mother of four (her husband is the novelist Michael Chabon), Waldman constructs her book around a diary she kept while experimenting for a few weeks with microdosing LSD. Microdosing, all the rage in Silicon Valley, involves taking small amounts of the drug (10–20 micrograms, about one-tenth of the dose consumed by most recreational users) every three days. Unlike Lin, Waldman has no desire to get high; the effects of LSD at this dosage are considered “subperceptual.” Instead, she wants to level out her mood swings, stop fighting with her husband and kids, and work more productively. But despite their differences in method, what Waldman and Lin want is essentially the same: to be less miserable, to form better emotional connections with the people in their lives, to pry themselves out of self-defeating patterns of thought, to be happier.

Can psychedelics do this? That’s one of the questions Pollan tackles in How to Change Your Mind. Figures like Leary and McKenna often claimed that widespread use of the drugs would lead to social, political, and even scientific revolution. McKenna reported that a paraphysical entity he called “the mushroom” possessed “the knowledge of hyperlight ships and how to build them.” This sort of nonsense doesn’t inspire much confidence in the average person, and even those of us who don’t think psychedelics ought to be Schedule I substances—even those of us who have taken the drugs occasionally ourselves—have learned to roll our eyes and check out of conversations where psychedelics are touted as tools of cosmic enlightenment. Nevertheless, Waldman’s modest expectations seem a bit timid. Surely Cary Grant counts as an equally reliable source, and he found LSD revelatory, not just a mood leveler. As the 2017 documentary Becoming Cary Grant, incorporating excerpts from the actor’s unpublished autobiography, testifies, the experience profoundly changed his life.

Pollan himself was no psychonaut when he became interested in the resurgence of scientific interest in psychedelics.

Pollan’s book is the baby bear’s bed in this triad: Neither too hard nor too soft, but just right. Like his previous two best-sellers, The Botany of Desire and The Omnivore’s Dilemma, it’s a mixture of history, profiles, first-person reportage, and wonder-struck rumination. The proportions of that chemical formula, it turns out, must be varied depending on the subject. There’s a certain species of popular social-science book published in the first decade of the 2000s—James Surowiecki’s The Wisdom of Crowds, Jonah Lehrer’s Proust Was a Neuroscientist, the entire oeuvre of Malcolm Gladwell—that now seems, for a variety of reasons, too wide-eyed and credulous in its championing of cutting-edge research that purportedly overturns our old suppositions and ushers in a new era of understanding humanity and its behavior. This approach felt fresh and fascinating when Pollan explored such seemingly mundane topics as plant reproduction and the food industry. His ability to reframe his subject in startling ways—for example, suggesting that agriculture can be seen as the wild success of certain plants in using humanity to propagate themselves—filled his books with intriguing intellectual novelties. But extravagant, utopian propositions about psychedelics are a dime a dozen. In this terrain, the hot commodities are common sense, skepticism, and scientific literacy.

How to Change Your Mind includes an account of how various psychedelic drugs found their way into American laboratories and homes, the great hiatus of research into their potential uses after they were outlawed in the ’60s and ’70s, and the “renaissance” of scientific interest in the drugs, beginning in the late 1990s and culminating in several government-funded studies today. Pollan himself was no psychonaut when he became interested in that resurgence. He’d tried psilocybin mushrooms twice in his 20s, then let the remaining stash of fungi molder in a jar in the back of a cabinet; the experience was “interesting” but not something he felt moved to repeat. What drew his attention to the subject later in life were two studies and a dinner party, where a 60ish “prominent psychologist,” married to a software engineer, explained that she and her husband found the “occasional use of LSD both intellectually stimulating and of value to their work.” One of the experiments, conducted at Johns Hopkins, UCLA, and NYU, found that large doses of psilocybin, when administered once or twice to patients who had received terminal cancer diagnoses, helped significantly reduce their fear and depression. The other study, conducted by some of the same researchers, observed the similarities between the results of high doses of psilocybin administered by teams of two therapists and what are commonly described as mystical experiences. The latter are episodes characterized by “the dissolution of one’s ego followed by a sense of merging with nature or the universe.” As Pollan notes, this hardly sounds like news to people accustomed to taking psychedelic drugs, but it marked the first validation of the idea in a rigorous scientific setting.

Further research using fMRI scanners has confirmed the similarity in brain activity between people meditating and people having certain kinds of psychedelic trips. But not all trips are the same, as anyone who has dropped acid can attest. Leary’s one great contribution to the understanding of psychedelics was his emphasis on what has become a mantra for contemporary researchers: set and setting. Set refers to what the person taking the drug expects or is told to expect from the experience, and setting refers to the circumstances of the trip itself: whether the subject is alone or with others, outside or inside, listening to particular kinds of music, wearing an eye mask, receiving guidance from someone they trust, being encouraged to explore ideas and feelings by a therapist, and so on.

Pollan took a couple of research trips himself in the course of writing How to Change Your Mind, with results that are interesting only to the extent that they help him make sense of other people’s accounts of their own journeys. The meat of the book is its chapters on the neuroscience of the drugs and their evident ability to suppress activity in a brain system known as the “default mode network.” The DMN acts as our cerebral executive, coordinating and organizing competing signals from other systems. It is, as Pollan sees it, the “autobiographical brain,” and the site of our ego. The long history of people reporting the sensation of their egos dissolving while under the influence of psychedelics meshes with this interpretation. It’s an experience with the potential to both terrify and, paradoxically, comfort those who undergo it.

Why should this effect prove so helpful to the depressed, addicted, and anxious? As Pollan explains it, these disorders are the result of mental and emotional “grooves” in our thinking that have become, as the DMN’s name suggests, default. We are how we think. The right psychedelic experience can level out the grooves, enabling a person to make new cerebral connections and briefly escape from “a rigidity in our thinking that is psychologically destructive.” The aerial perspective this escape offers doesn’t immediately evaporate either. The terminal cancer patients in the psilocybin study felt lasting relief as a result of the glimpse the drugs gave them of a vista beyond the limitations of their own egos—even the ones who didn’t believe in God or other supernatural forces. In this light, it’s easier to see how psychedelics helped both Lin and Waldman. Each describes newfound abilities to lift themselves out of patterns that made them miserable. At one point, Lin went so far as to delete his social media accounts, cut the cord on his Wi-Fi router, and toss his MacBook in a dumpster—which, if you know anything about Tao Lin, does sound like a step in the right direction. (That change, unfortunately, didn’t last, and by the next morning he was on his way to the Apple Store in SoHo.) It’s also worth noting that Grant retired from film acting at the age of 62, not long after his LSD therapy, and never seemed to miss it.

If How to Change Your Mind furthers the popular acceptance of psychedelics as much as I suspect it will, it will be by capsizing the long association, dating from Leary’s time, between the drugs and young people. Pollan observes that the young have had less time to establish the cognitive patterns that psychedelics temporarily overturn. But “by middle age,” he writes, “the sway of habitual thinking over the operations of the mind is nearly absolute.” What he sought in his own trips was not communion with a higher consciousness so much as the opportunity to “renovate my everyday mental life.” He felt that the experience made him more emotionally open and appreciative of his relationships. Both Waldman and Lin report similar effects, even though Waldman never actually tripped. The promise of hyperlight travel, revolution, and spiritual transcendence be damned: If psychedelics can help cure the midlife crises of disaffected baby boomers and Gen Xers, then it’s only a matter of time until we’ll be able to pick them up with a prescription at our local pharmacy.

How to Change Your Mind: What the New Science of Psychedelics Teaches Us About Consciousness, Dying, Addiction, Depression, and Transcendence by Michael Pollan. Penguin Press.

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