How to Change Your Mind Summary: Complete Psychedelics History
Based on Michael Pollan’s best-selling book “How to Change Your Mind”.
Michael Pollan concludes his bestselling book "How to Change Your Mind" with a striking warning: "The psychedelic experience has the remarkable ability to challenge nearly every fixed idea we hold about our identity."
What follows is a compelling and detailed chronicle of our journey with these transformative molecules—how we uncovered their potential as wonder drugs, demonized them as public enemies, and are now, in the 2020s, reigniting our understanding of their extraordinary capacity for healing and growth.
Prehistory and Indigenous Use (Thousands of Years BCE – 19th Century).
Pollan begins the story not in a laboratory, but in the deep past. Human beings have been intentionally altering consciousness with plants and fungi for at least ten thousand years, and probably far longer. The evidence is scattered across continents:
7,000–9,000-year-old rock art in the Tassili n'Ajjer plateau in Algeria shows bee-headed, mushroom-bearing dancers.
5 700-year-old peyote buttons were recovered from the Shumla Cave in Texas.
4,000–5,000-year-old ceramic vessels from coastal Ecuador contain traces of Banisteriopsis caapi (the ayahuasca vine).
2,000-year-old snuff tablets from the Tiwanaku culture in Bolivia contain DMT, bufotenine, and harmine.
The famous 1,000-year-old Chavín de Huántar temple in Peru is filled with carvings of the San Pedro cactus (mescaline) and snuff-taking jaguar priests.
In Mesoamerica, the Aztecs referred to psilocybin mushrooms as teonanácatl, meaning "flesh of the gods." Bernardino de Sahagún's 16th-century work, the Florentine Codex, details their use in coronation rites and divination. The Mazatec people of Oaxaca maintained this tradition into the 20th Century, and their most renowned curandera, María Sabina, gained international fame when R. Gordon Wasson visited her in 1955.
Peyote has been used by the Huichol, Cora, and Tarahumara peoples for thousands of years during their significant pilgrimages. Ayahuasca (known as yagé, natem, or caapi by different tribes) serves as the central sacrament for at least 72 Amazonian ethnic groups.
These substances were never intended for recreational use; instead, they were administered in sacred contexts by trained shamans, who often underwent years of apprenticeship and dietary preparation. In these practices, the container—consisting of ritual, song, and community—was just as important as the psychoactive molecule itself.
Western Rediscovery (1880s–1940s).
The exploration of these substances by the West occurred gradually and often accidentally:
1887–1897: American anthropologists James Mooney and Weston La Barre document the peyote rituals of the Native American Church.
1897: Arthur Heffter isolates mescaline, marking the discovery of the first pure psychedelic compound.
1920s: German pharmacologists Kurt Beringer and Ernst Späth publish detailed accounts of their self-experiments with mescaline.
1938: Albert Hofmann, while working at Sandoz in Basel, synthesizes LSD-25 while searching for a circulatory stimulant derived from ergot. The compound is shelved for five years.
April 16, 1943: Hofmann accidentally absorbs a trace of LSD through his fingertips, leading to the world's first LSD trip.
April 19, 1943: Known as "Bicycle Day," Hofmann deliberately consumes 250 µg of LSD and rides home through a visually distorted Basel, describing the experience as "an uninterrupted stream of fantastic pictures, extraordinary shapes with an intense, kaleidoscopic play of colors."
1947–1966: Sandoz markets LSD under the trade name Delysid and provides free samples to any licensed psychiatrist who requests them.
The First Wave – The Golden Age of Research (1949–1965).
Between 1949 and 1965, psychedelics became a groundbreaking tool in psychiatry, leading to the emergence of two distinct therapeutic approaches:
Psycholytic Therapy ("Mind-Loosening") – Practiced in Europe and Hollywood.
This method involved administering repeated low-to-medium doses of LSD (ranging from 50 to 200 micrograms) to reduce ego defenses and facilitate the process of psychoanalysis. In Los Angeles, psychiatrist Oscar Janiger treated over 900 patients, including Cary Grant, Jack Nicholson, Anaïs Nin, and Aldous Huxley. Cary Grant even stated to reporters that LSD therapy was "the greatest thing that ever happened to me."
In Europe, Hanscarl Leuner in Göttingen and Jan Bastiaans in Leiden also practiced psycholytic therapy, with Bastiaans focusing on LSD-assisted trauma work with Holocaust survivors.
Psychedelic Therapy ("Mind-Manifesting") – North America.
This is the classic psychedelic therapy model: one single, heroic dose—usually 300 to 800 micrograms of LSD—given in a setting that looks more like a tasteful living room than a hospital room. The patient lies on a comfortable couch, eyes covered with a soft mask, headphones feeding a carefully chosen playlist of classical music (lots of Brahms, Bach, and Vaughan Williams).
The idea is to eradicate external distractions and let the medicine take the person all the way in—past the chatter of the everyday mind and straight into what feels like full ego death and mystical rebirth.
The undisputed godfather of this high-dose approach was the mysterious Captain Al Hubbard—former OSS spook, uranium millionaire, and, bizarrely, a Knight of the Equestrian Order of the Holy Sepulchre (the Vatican gave him the sword and everything). Al turned into the Johnny Appleseed of LSD. He personally sat with over six thousand people, handing them the cup and talking them through the other side.
His guest list reads like a mid-century Who's Who: Bill Wilson (the co-founder of AA), Aldous Huxley, Catholic priests by the dozen, top psychiatrists, and even a few Canadian MPs. He was convinced the experience could cure alcoholism, awaken spirituality, and maybe even prevent nuclear war. Most of the time, he was right.
Major centers for psychedelic therapy include:
- Spring Grove State Hospital, Maryland (later known as the Maryland Psychiatric Research Center).
- Saskatchewan, where Humphry Osmond and Abram Hoffer conducted research.
- Hollywood Hospital in Vancouver.
- The International Foundation for Advanced Study in Menlo Park, led by Myron Stolaroff.
Key milestones:
1954: Aldous Huxley publishes The Doors of Perception – the philosophical bible of the movement.
1957: Humphry Osmond coined the word "psychedelic" in a letter to Huxley.
1955–1965: More than 1,000 peer-reviewed papers, 40,000 patients treated, six international conferences. Many psychiatrists genuinely believed they were witnessing the birth of a revolution in mental health.
Harvard, Timothy Leary, and the Beginning of the End (1960–1963).
In the summer of 1960, Timothy Leary, a 39-year-old Harvard University psychology lecturer, consumed psilocybin mushrooms in Cuernavaca, Mexico. He later described this experience as "the deepest religious experience of my life." Upon returning to Harvard, he and Richard Alpert (who would later be known as Ram Dass) initiated the Harvard Psilocybin Project using Sandoz pills.
They administered the drug to graduate students, artists, theologians, and prisoners. One of the most notable studies from this period is the 1962 Good Friday Experiment, which was part of Walter Pahnke's doctoral thesis. In this experiment, 20 divinity students participated; half received 30 mg of psilocybin, while the other half received a placebo. Nine out of the ten students who took the psilocybin reported having profound mystical experiences, compared to only one in the control group.
Leary quickly moved away from scientific rigor, embracing an evangelistic approach with the mantra, "Turn on, tune in, drop out." Undergraduates were dosed, parties spilled out of his home in Newton, and media attention intensified. Ultimately, Harvard fired Leary and Alpert in May 1963. This marked a pivotal moment when the therapeutic and countercultural movements began to merge, with a significant impact on society.
The 1960s Counterculture Explosion (1963–1970).
1963: Sandoz Pharmaceuticals halts all distribution of LSD in the U.S.
1964–1966: Augustus Owsley Stanley III produces tens of millions of doses of pure LSD in the San Francisco Bay Area. Ken Kesey and the Merry Pranksters tour America on their psychedelic bus, "Furthur," hosting Acid Tests.
1966: California bans LSD on October 6, an event now known as "LSD Day." A federal ban followed in 1968.
1967: The Human Be-In event takes place in Golden Gate Park, marking the Summer of Love, where 100,000 young people converge on Haight-Ashbury.
Media hysteria escalates, with claims that LSD causes chromosome damage (later debunked), as well as fears of "flashbacks" and exaggerated stories of children staring at the sun until they go blind.
Richard Nixon labels Timothy Leary "the most dangerous man in America."
By 1970, virtually all legal research involving psychedelics on humans had been shut down worldwide.
Schedule I and the Thirty-Year Dark Age (1970–1990).
October 27, 1970: The U.S. Controlled Substances Act classifies LSD, psilocybin, DMT, and mescaline (with the exception of peyote used by the Native American Church) as Schedule I substances, indicating they have "no currently accepted medical use and a high potential for abuse."
1971: The United Nations Convention on Psychotropic Substances mandates that nearly every country comply with these regulations.
As a result, research funding vanishes, and many careers are ruined. The term "psychedelic" becomes taboo in academic circles.
Pollan refers to this period as "the thirty-year dark age."
The Underground and the First Sparks of Revival (1970s–1990s).
Therapy does not disappear; it goes underground. A network of therapists trained in the 1950s and 1960s continues to treat patients illegally using LSD and later MDMA until the mid-1980s.
In 1979 and 1996, Alexander ("Sasha") and Ann Shulgin published "PiHKAL" and "TiHKAL," which are detailed synthesis manuals and trip reports that became crucial resources in the underground scene.
From 1985 to 1987, MDMA was classified as an emergency-scheduled substance after it gained popularity as "Ecstasy" in clubs in Texas and New York. This backlash leads to the founding of Rick Doblin's Multidisciplinary Association for Psychedelic Studies (MAPS) and spurs the modern drug-policy reform movement.
The Second Wave – The Renaissance (1990–2018).
A new generation of researchers, intent on learning from the mistakes of the 1960s, embarks on a fresh beginning:
1990s:
1990–1995: Rick Strassman obtains the first DEA Schedule I research license in decades, conducting the only legal DMT study in the U.S. at the University of New Mexico.
Meanwhile, Franz Vollenweider in Zurich receives special permission from Swiss authorities to conduct human brain-imaging studies using psilocybin and LSD.
2000s:
2000: The FDA approves the first modern human psilocybin study at Harbor-UCLA.
2001: Roland Griffiths restarts psilocybin research at Johns Hopkins University.
2006: Griffiths publishes a landmark paper demonstrating that high-dose psilocybin can induce genuine mystical experiences that lead to lasting positive personality changes. This paper becomes the most cited work of the psilocybin renaissance.
2008: Charles Grob publishes the first modern psilocybin study focused on cancer patients.
2010s:
2010–2016: Robin Carhart-Harris and David Nutt at Imperial College London publish groundbreaking fMRI studies demonstrating that psilocybin significantly suppresses the default mode network, which is associated with the sense of ego.
2014: The first European trial testing psilocybin for depression takes place at Imperial College.
2016: Landmark studies conducted by Johns Hopkins University and NYU reveal that one or two doses of psilocybin, combined with therapy, lead to substantial and lasting reductions in depression and anxiety in cancer patients, with response rates between 70% and 80%.
2017–2018: The FDA grants "breakthrough therapy" designation to psilocybin-assisted therapy for treatment-resistant depression (Compass Pathways) and later for major depressive disorder.
2018–2019: Johns Hopkins establishes the Center for Psychedelic and Consciousness Research with $17 million in private funding, while Imperial College opens the world's first academic psychedelic research center. In May 2019, Denver decriminalized psilocybin mushrooms, followed by Oakland in June 2019.
Where Pollan Leaves Us (2018 – and the Trajectory Since).
In 2018, when this book was published, psychedelics were no longer considered fringe substances. They emerged as some of the most promising developments in psychiatry in decades. Studies show that single-dose or short courses of psilocybin therapy have significantly greater effects on depression, addiction, and end-of-life distress than SSRIs and other existing treatments.
And right now, in 2025, MDMA-assisted therapy for PTSD is finishing Phase 3 with numbers that still feel unreal: roughly nine out of ten patients no longer meet the criteria for PTSD after three guided sessions. That's the kind of result that makes even the most jaded psychiatrist sit up straight.
Yet the big, unresolved question still hangs in the air: are we turning these molecules into expensive, patented pills locked behind a therapist's office and an insurance code, or are we finally ready to admit that sometimes the best medicine looks suspiciously like an ancient religious sacrament?
Walk into any of today's trials, and you'll see the ghost of the sixties sitting quietly in the corner.
The researchers wear pressed shirts and sensible shoes, they say "classic hallucinogen" instead of "psychedelic," and they flinch if anyone mentions the word "trip." They've learned the hard way: look too much like the past and the whole thing gets shut down again.
So the Renaissance is happening, but it's wearing a tie. Whether the tie ever comes off—that's the part none of us get to write yet.
Pollan offers a final reflection: "The psychedelic experience—in whatever dose, set, or setting—still has the power to unsettle just about every fixed idea we have about who we are and where we fit into the scheme of things."
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Aldous Huxley – The Doors of Perception (1954)
R. Gordon Wasson – "Seeking the Magic Mushroom" (Life magazine, 1957)
Stanislav Grof – Realms of the Human Unconscious (1975)
Alexander & Ann Shulgin – PiHKAL (1991) and TiHKAL (1997)
Roland Griffiths et al. – "Psilocybin can occasion mystical-type experiences…" (Psychopharmacology, 2006)
Robin Carhart-Harris et al. – various Imperial College fMRI papers (2012–2018)
The Johns Hopkins & NYU 2016 cancer-anxiety studies (published simultaneously in the Journal of Psychopharmacology)
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This entire article is a chapter-by-chapter synthesis of Michael Pollan's How to Change Your Mind (Penguin Press, 2018). All historical claims, dates, and study outcomes are drawn directly from the book and its 80-page bibliography and notes section.
