Key Researchers in Psilocybin Science

Albert Hofmann (1906–2008)

Swiss Chemist — Sandoz Laboratories, Basel, Switzerland

Albert Hofmann is perhaps the single most consequential figure in the history of psychedelic science. Born in Baden, Switzerland, Hofmann spent his career at Sandoz Pharmaceuticals in Basel, where he was investigating ergot alkaloids in search of respiratory and circulatory stimulants. On 16 April 1943 — a date now celebrated annually as “Bicycle Day” — he became the first person to experience the effects of lysergic acid diethylamide (LSD), a compound he had first synthesised in 1938 but set aside as seemingly unremarkable.

His contribution to psilocybin research came fifteen years later. Working with samples of Psilocybe mexicana mushrooms provided by the ethnomycologist R. Gordon Wasson, Hofmann successfully isolated, identified, and chemically synthesised both psilocybin and psilocin in 1958 and 1959 respectively. This was not merely a laboratory achievement: by producing a chemically pure, standardisable form of the active principle, Hofmann made it possible for other researchers worldwide to conduct controlled scientific studies without relying on raw mushroom material of variable potency. Every modern psilocybin clinical trial traces its scientific lineage directly to this work.

Hofmann described his experiences in his landmark autobiography LSD: Mein Sorgenkind (published in English as LSD: My Problem Child, 1980), which remains essential reading for anyone interested in the history of psychedelic science. He also co-authored The Road to Eleusis (1978) with Gordon Wasson and classicist Carl Ruck, proposing that an ergot-based psychedelic potion called kykeon may have been used in the ancient Greek Eleusinian Mysteries. Hofmann lived to 102 and in his final years expressed measured optimism about the renewal of medical research into LSD and psilocybin, telling interviewers that he hoped to see these compounds rehabilitated as therapeutic tools before he died.

Key legacy: Chemical isolation and synthesis of psilocybin (1958) and psilocin (1959); provided the pharmacological foundation for all subsequent controlled research; authored the definitive memoir of psychedelic discovery.

R. Gordon Wasson (1898–1986)

American Banker & Ethnomycologist — New York; fieldwork in Oaxaca, Mexico

Robert Gordon Wasson was a vice-president at J.P. Morgan & Co. who pursued ethnomycology as a lifelong passion alongside his banking career. His obsession with fungi — sparked by a honeymoon discovery that his Russian wife Valentina was enthusiastically mycophilic while he, like most Anglo-Americans, was deeply mycophobic — led him across decades of research into the cultural role of mushrooms across civilisations.

In 1955, Wasson and his colleague Allan Richardson became among the first outsiders to participate in a traditional Mazatec velada (healing ceremony) in Huautla de Jimenez, Oaxaca, Mexico, led by the revered curandera Maria Sabina. Wasson later arranged for Hofmann to visit Oaxaca, leading to the chemical identification of the active principles. His 1957 Life magazine article, “Seeking the Magic Mushroom,” was the first widely-read English-language account of the psychedelic mushroom experience and introduced millions of Americans to a practice that had existed in Mesoamerica for millennia. This article is often cited as the starting gun for the 1960s Western psychedelic movement.

Wasson spent the remainder of his scholarly life documenting the mycological dimensions of human spiritual experience. His major work, The Wondrous Mushroom: Mycolatry in Mesoamerica (1980), remains a standard reference in ethnomycology. He also co-authored Soma: Divine Mushroom of Immortality (1968), arguing controversially that the Vedic ritual drink Soma was derived from the fly agaric mushroom Amanita muscaria. Wasson’s work bridged two worlds that had never spoken to one another: ancient indigenous healing traditions and Western pharmacological science. His relationship with Maria Sabina has been subject to subsequent ethical scrutiny — the exposure she received following the Life article brought unwanted attention to her community — and this tension remains an important reminder about the ethics of documenting indigenous practices.

Key legacy: Documented participation in Mazatec psilocybin ceremony (1955); “Seeking the Magic Mushroom” (1957, Life); provided the biological specimens from which Hofmann isolated psilocybin; pioneered ethnomycology as a discipline.

Alexander “Sasha” Shulgin (1925–2014)

Chemist & Pharmacologist — Lafayette, California, USA

Alexander Theodore Shulgin is one of the most prolific and consequential chemists in the history of psychoactive drug research. Holding a doctorate in biochemistry from UC Berkeley and having worked at Dow Chemical (where he developed the profitable pesticide Zectran), Shulgin negotiated a DEA Schedule I researcher licence that allowed him to legally synthesise and study controlled substances. From a private laboratory on his farm in Lafayette, California, Shulgin personally developed and, with his wife Ann, bioassayed hundreds of novel psychoactive compounds over four decades.

His contributions to tryptamine pharmacology — the chemical class that includes psilocybin — were encyclopaedic. He synthesised and characterised the subjective and pharmacological effects of dozens of tryptamine variants, providing the research community with a vast map of structure-activity relationships. His two-volume magnum opus, PIHKAL: Phenethylamines I Have Known and Loved (1991, co-authored with Ann Shulgin) and TIHKAL: Tryptamines I Have Known and Loved (1997), are part autobiography, part chemistry textbook, and part pharmacological encyclopedia. TIHKAL in particular includes detailed synthesis routes and pharmacological notes for 55 tryptamine compounds. Both books remain standard references for researchers in psychedelic pharmacology.

Shulgin is also credited with reintroducing MDMA to therapeutic research in the late 1970s, after learning of Leo Zeff’s use of the compound in psychotherapy and spreading the knowledge to a network of therapists. His DEA licence was ultimately revoked in 1994 following a critical inspection of his laboratory. He continued to lecture and write until advancing dementia curtailed his activities. Ann Shulgin continued his advocacy work after his death in 2014.

Key legacy: Synthesis and bioassay of hundreds of psychoactive tryptamines and phenethylamines; PIHKAL (1991) and TIHKAL (1997) remain essential references; reintroduced MDMA to psychotherapy; established the self-experimentation tradition in psychedelic pharmacology.

Amanda Feilding (born 1943)

Founder & Director — The Beckley Foundation, Oxford, UK

Amanda Feilding, Countess of Wemyss and March, has been one of the most persistent and influential advocates for psychedelic research since the field was effectively shuttered in the early 1970s. She founded the Beckley Foundation in Oxford in 1998 with the dual mission of advancing scientific research into altered states of consciousness and developing evidence-based drug policy reform. The Foundation operates as an independent think tank and research charity, collaborating with academic institutions worldwide.

Feilding’s most consequential strategic move was co-founding the Beckley/Imperial Research Programme with Professor David Nutt and Dr Robin Carhart-Harris at Imperial College London. This collaboration produced several landmark studies, including the first neuroimaging study of psilocybin’s effects on brain activity (Carhart-Harris et al., 2012, PNAS) and the first fMRI study examining psilocybin in treatment-resistant depression (Carhart-Harris et al., 2016, The Lancet Psychiatry). Feilding personally funded or co-funded these studies at a time when government grants for psychedelic research were essentially unavailable.

She has also engaged at the policy level for decades, making formal submissions to the UN Commission on Narcotic Drugs and engaging with the UK Advisory Council on the Misuse of Drugs. She edited the academic volume Neuroscience of Consciousness (Oxford University Press, 2017) and has been awarded honorary doctorates in recognition of her contributions. Her approach — combining philanthropic funding, scientific collaboration, and policy advocacy — created the template that organisations like MAPS subsequently adopted at larger scale.

Key legacy: Founded the Beckley Foundation (1998); co-founded Beckley/Imperial Research Programme; privately funded the first psilocybin neuroimaging studies; UN-level drug policy advocacy since the 1990s; edited Neuroscience of Consciousness (2017).

Rick Strassman (born 1952)

Clinical Associate Professor of Psychiatry — University of New Mexico School of Medicine

Rick Strassman holds a singular place in the history of modern psychedelic research: he conducted the first human psychedelic study approved by the US government in more than two decades. Between 1990 and 1995, at the University of New Mexico under FDA and DEA approval, Strassman administered intravenous N,N-dimethyltryptamine (DMT) to 60 volunteers in a controlled clinical setting. This study broke a prohibition that had effectively frozen human psychedelic research in the United States since the early 1970s, demonstrating that such research could be conducted safely and responsibly within regulatory frameworks.

Strassman had trained in conventional psychiatry and psychopharmacology, and his methodological rigour — standardised screening, trained session monitors, structured rating instruments, careful attention to set and setting — established a template that subsequent clinical trials, including all the major Johns Hopkins and Imperial College psilocybin studies, largely adopted. His sessions produced an extraordinary range of reports from volunteers, many describing contact with apparently autonomous non-human intelligences, experiences that Strassman documented without explanation but with meticulous care.

His popular account of this research, DMT: The Spirit Molecule (2000, Park Street Press), became one of the best-selling books in psychedelic science and was adapted into a documentary film in 2010. While the “endogenous DMT” hypothesis he explored — the idea that the pineal gland produces DMT as a neurochemical mediator of spiritual experience — remains speculative and contested, it stimulated significant discussion within both scientific and popular communities. His later work includes Inner Paths to Outer Space (2008) and DMT and the Soul of Prophecy (2014). He has remained an active commentator on psychedelic science while maintaining clinical practice in New Mexico.

Key legacy: First US government-approved human psychedelic study in 20+ years (1990–1995); established clinical methodology for human DMT/psychedelic administration that informed subsequent trials; DMT: The Spirit Molecule (2000) popularised endogenous psychedelic research.

Roland Griffiths (1946–2023)

Professor of Psychiatry & Neuroscience — Johns Hopkins University School of Medicine, Baltimore, MD

Roland Griffiths was arguably the most important figure in the modern revival of psilocybin research. Having spent more than 30 years conducting rigorous behavioural pharmacology research on caffeine, sedative-hypnotics, and drug self-administration, Griffiths brought unimpeachable scientific credibility to psychedelic research at a moment when it desperately needed it. His 2006 paper in Psychopharmacology — “Psilocybin can occasion mystical-type experiences having substantial and sustained personal meaning and spiritual significance” — was a watershed. Published in a peer-reviewed pharmacology journal, it reported that a majority of healthy adult volunteers rated a psilocybin experience among the most meaningful of their entire lives, with effects on well-being persisting at 14-month follow-up. The paper formally reopened a scientific conversation that had been closed for 35 years.

His subsequent research deepened and broadened these findings. A 2011 paper in Journal of Psychopharmacology documented lasting increases in openness — a personality trait not typically considered malleable in adults — following psilocybin sessions. His 2016 study in Journal of Psychopharmacology, conducted in parallel with the NYU study by Stephen Ross, examined psilocybin for existential distress in cancer patients and found dramatic, durable reductions in anxiety and depression. A 2020 study (Davis et al.) in JAMA Psychiatry demonstrated rapid antidepressant effects in major depressive disorder in an open-label design.

In 2019, Griffiths founded the Johns Hopkins Center for Psychedelic and Consciousness Research, the first such centre at a major US university in the modern era. The centre drew significant private philanthropic funding and quickly became the world’s most productive psychedelic research programme. Griffiths was diagnosed with stage 4 glioblastoma (brain cancer) in 2023. Rather than retreat from research, he continued working and, in a detail that encapsulates the profound humanity of his scientific life, used psilocybin himself to address end-of-life anxiety. He died on 16 October 2023. Obituaries in The New York Times, The Lancet, and Nature recognised him as the father of the modern clinical psilocybin research movement.

Key publications: Griffiths et al. (2006, Psychopharmacology); Griffiths et al. (2011, J Psychopharmacol); Griffiths et al. (2016, J Psychopharmacol); Davis et al. (2021, JAMA Psychiatry).

Matthew Johnson

Susan Hill Ward Professor in Psychedelics and Consciousness — Johns Hopkins University School of Medicine

Matthew Johnson joined the Johns Hopkins research group as a postdoctoral fellow under Roland Griffiths and has since become one of the most prolific and versatile psilocybin clinical researchers in the world. He holds a PhD in psychology from the University of Vermont and has published extensively across a range of clinical applications of psilocybin, with a particular focus on substance use disorders.

His 2014 pilot study on psilocybin-facilitated smoking cessation, published in Drug and Alcohol Dependence, produced results that startled the addiction research community: 80 percent of participants had abstained from tobacco at six-month follow-up, a rate that substantially exceeded anything achieved by standard smoking cessation pharmacotherapies or behavioural interventions. A 2017 follow-up confirmed that these effects were largely maintained at 12 months. While the study was uncontrolled (no placebo comparison) and involved a highly selected and motivated sample, the effect sizes were large enough to justify a full randomised controlled trial, which is currently underway.

Johnson is also co-author of the foundational safety guidelines for psychedelic research, published in 2008 in Psychopharmacology (Johnson, Richards, & Griffiths), which have been widely cited and adopted as the de facto standard for human psychedelic administration protocols. These guidelines cover screening, preparation, session management, and integration, and have been updated in subsequent reviews. As current director of the Johns Hopkins Center for Psychedelic and Consciousness Research, he leads multiple active trials examining opioid use disorder, eating disorders, and the psychological and neurobiological mechanisms of psilocybin action.

Key publications: Johnson et al. (2014, Drug and Alcohol Dependence — smoking cessation pilot); Johnson et al. (2017, follow-up); Johnson, Richards & Griffiths (2008, Psychopharmacology — safety guidelines).

Robin Carhart-Harris

Director, Psychedelics Division — UCSF; formerly Imperial College London

Robin Carhart-Harris is the most cited neuroscientist working specifically on psychedelics and has produced the field’s most ambitious theoretical frameworks. He completed his PhD at the University of Bristol and joined David Nutt’s group at Imperial College London, where he remained until 2021 before moving to the University of California San Francisco as founding Director of the Psychedelics Division at Neuroscape.

His 2012 paper in PNAS — the first study to image the brain under psilocybin using fMRI — was revelatory. It revealed that psilocybin does not simply excite the brain but causes paradoxical decreases in activity in the default mode network (DMN), a set of interconnected brain regions associated with self-referential thought, mind-wandering, rumination, and the sense of self. This finding provided a neurobiological correlate for the often-reported dissolution of the ego boundary under psychedelics and suggested a mechanism by which psilocybin might interrupt the ruminative thought patterns characteristic of depression.

He subsequently developed the “entropic brain” hypothesis (2014, Frontiers in Human Neuroscience), proposing that psychedelics increase the entropy — i.e. the complexity and unpredictability — of brain activity, temporarily destabilising habitual neural patterns and enabling new ones to form. In 2019, he and Karl Friston extended this into the REBUS (“Relaxed Beliefs Under Psychedelics”) model (Pharmacological Reviews), which proposes that psychedelics work by attenuating the brain’s top-down predictive processing, allowing suppressed bottom-up sensory and emotional signals to reach consciousness. REBUS has become the most widely debated theoretical framework in the field. His 2021 randomised controlled trial in The New England Journal of Medicine directly compared psilocybin therapy to the SSRI escitalopram in patients with moderate-to-severe depression over six weeks, finding comparable reductions in depression scores but significantly greater improvements in emotional processing and well-being in the psilocybin group — a result with major implications for psychiatry.

Key publications: Carhart-Harris et al. (2012, PNAS — first psilocybin fMRI); Carhart-Harris (2014, Frontiers Human Neurosci — entropic brain); Carhart-Harris & Friston (2019, Pharmacol Rev — REBUS); Carhart-Harris et al. (2021, NEJM — psilocybin vs SSRIs).

David Nutt (born 1951)

Edmond J. Safra Chair in Neuropsychopharmacology — Imperial College London; Founder, Drug Science

David Nutt is one of Britain’s most prominent and periodically controversial pharmacologists. He trained in medicine at Cambridge and completed his psychiatric and research training in the UK and at the National Institutes of Health in Bethesda, Maryland. He held the position of Chair of the UK Advisory Council on the Misuse of Drugs (ACMD) from 2008 until his dismissal in 2009 — an event that generated substantial public and scientific commentary.

The dismissal arose from his publication of a paper in the Journal of Psychopharmacology calculating that, on a range of harm metrics, horse riding caused comparable or greater societal and individual harm than ecstasy, and that alcohol caused far greater harm than cannabis, LSD, or ecstasy. Home Secretary Alan Johnson dismissed him on the grounds that “it is not the role of the ACMD to challenge government drug policy.” The scientific community largely rallied behind Nutt, and five other members of the ACMD resigned in protest. The episode became a celebrated case study in the tension between evidence-based policy and political drug policy.

Following his dismissal, Nutt founded Drug Science, a charity that promotes independent scientific evidence on drugs. He continued his research programme at Imperial College London, including the Centre for Psychedelic Research. His 2010 paper in The Lancet ranking 20 drugs by overall harm to self and others placed alcohol at the top of the list, ahead of heroin and crack cocaine — a finding widely cited in drug policy debates worldwide. His psychedelic research includes studies on psilocybin’s safety profile and a major programme of neuroimaging research in collaboration with Carhart-Harris. He has also published on the potential use of LSD microdosing and has been a consistent advocate for rescheduling psilocybin under UK law to facilitate research.

Key publications: Nutt et al. (2010, The Lancet — drug harm rankings); Nutt et al. (2016, psilocybin safety review); multiple neuroimaging studies with Carhart-Harris at Imperial College London.

Franz Vollenweider

Professor of Psychiatry — University of Zurich; Director, Heffter Research Center Zurich

Franz Vollenweider has been conducting neurobiological and pharmacological research on psilocybin and other classical psychedelics since the early 1990s, making him one of the longest-serving active researchers in the modern era of the field. His group at the Psychiatric Hospital of the University of Zurich (the Burghölzli, famous in psychiatric history) has been particularly important for establishing the neurobiological underpinnings of psychedelic action.

His early work in the 1990s used positron emission tomography (PET) to study metabolic brain activity under psilocybin, finding paradoxical patterns of hyperactivation in fronto-parietal and striatal regions. A landmark 1997 paper in Neuroreport provided among the first quantitative neuroimaging data on a classical psychedelic in humans. He also developed a four-factor model of psychedelic phenomenology based on systematic administration of the Altered States of Consciousness (ASC) questionnaire, which has been used in numerous subsequent studies to characterise the quality of psychedelic experiences.

Vollenweider’s group has been instrumental in characterising the role of the 5-HT2A serotonin receptor in psychedelic action, demonstrating through ketanserin (a 5-HT2A antagonist) pretreatment studies that blockade of this receptor prevents psilocybin’s perceptual and psychological effects. This mechanistic work established the 5-HT2A receptor as the critical pharmacological target of psilocybin and has informed the development of next-generation psychoplastogens — compounds designed to promote neuroplasticity without producing a full psychedelic experience. His 2010 review with Michael Kometer in Nature Reviews Neuroscience remains the definitive overview of the neurobiology of psychedelic drug action.

Key publications: Vollenweider et al. (1997, Neuroreport); Vollenweider & Kometer (2010, Nat Rev Neurosci — neurobiology of psychedelic action); multiple 5-HT2A mechanism studies from the Zurich group.

Rosalind Watts

Clinical Psychologist — Founder, Awakened Futures; formerly Imperial College London

Rosalind Watts brings a fundamentally different perspective to psychedelic research from most of her colleagues: she approaches the field as a clinical psychologist and therapist rather than a pharmacologist or neuroscientist. Her contribution has been to articulate, from the inside of the therapeutic encounter, what actually happens psychologically during and after psilocybin-assisted therapy — and to build theoretical and practical frameworks around those observations.

Watts was the lead therapist on the Imperial College London psilocybin depression study (2016–2017), a milestone open-label study that treated 20 patients with treatment-resistant depression who had failed at least two prior antidepressant treatments. Her qualitative analysis of participants’ accounts produced a conceptual framework centred on the idea that depression is fundamentally a state of “disconnection” — from self, others, world, and a sense of meaning — and that psilocybin uniquely enables “reconnection” along all these dimensions. This reconnection framework, published in Frontiers in Psychiatry and related journals, has been influential in shaping the therapeutic models used in subsequent studies.

She subsequently developed the ACE (Accept, Connect, Embody) therapeutic model, a structured approach to psilocybin-assisted therapy that emphasises surrender, interpersonal warmth between guide and participant, and somatic awareness. She also introduced the concept of ecological awareness as a meaningful therapeutic outcome — many patients reporting not just personal healing but an enhanced sense of connectedness to the natural world. Her “Dimensions of Consciousness” framework provides therapists with a phenomenological map of the psychedelic experience space. Since leaving Imperial College, she has led Awakened Futures and the ACER Integration programme, which trains therapists internationally in psilocybin-assisted therapy methods.

Key contributions: Lead therapist, Imperial College depression study (2016); disconnection/reconnection framework for depression; ACE therapeutic model; ecological awareness as therapeutic outcome; ACER Integration therapist training programme.

Michael Pollan (born 1955)

Author & Journalist — Harvard University (visiting); University of California Berkeley

Michael Pollan is not a scientist by training — he is the author of celebrated books on food, agriculture, and the human relationship with the natural world, including The Omnivore’s Dilemma and In Defense of Food. His inclusion in any list of key psychedelic researchers reflects the unusual fact that his 2018 book How to Change Your Mind: What the New Science of Psychedelics Teaches Us About Consciousness, Dying, Addiction, Depression, and Transcendence (Penguin Press) probably did more to shift mainstream American and European attitudes toward psilocybin research than any individual scientific paper published in the preceding decade.

The book, which spent months on the New York Times bestseller list and has sold millions of copies worldwide, combined investigative reporting on the state of psychedelic science with memoir: Pollan underwent personally guided psilocybin, LSD, ayahuasca, and 5-MeO-DMT experiences in the course of his research and wrote about them with characteristic literary intelligence and intellectual honesty. By framing the subject through the lens of a sceptical, middle-aged, non-counterculture voice, Pollan made the topic accessible and credible to an enormous general readership that would never have encountered a peer-reviewed pharmacology paper.

The downstream effects were concrete: donations to psychedelic research institutions increased significantly after the book’s publication; legislative initiatives in Oregon (Measure 109, 2020), Colorado, and other jurisdictions to legalise therapeutic psilocybin use gained momentum partly on the basis of public sentiment the book helped shape; and a Netflix documentary series based on the book (2022) extended its reach to an even wider global audience. Pollan co-founded the UC Berkeley Center for the Science of Psychedelics in 2020, which conducts both scientific research and public science communication. His willingness to discuss his own psychedelic experiences publicly, at an age and from a professional position that made such disclosure personally risky, modelled a new kind of public engagement with the topic.

Key contributions: How to Change Your Mind (2018) — NYT bestselling science communication; co-founded UC Berkeley Center for the Science of Psychedelics (2020); Netflix series (2022); pivotal role in shifting mainstream public and legislative attitudes toward psychedelic research.

Michael Bogenschutz

Professor of Psychiatry — NYU Grossman School of Medicine / NYU Langone Health, New York

Michael Bogenschutz is one of the leading clinical researchers applying psilocybin to the treatment of alcohol use disorder (AUD), a condition that causes enormous global morbidity and for which existing pharmacological treatments have modest effect sizes. His research trajectory moved from standard addiction psychiatry into psychedelic-assisted therapy over the 2010s as preliminary evidence accumulated suggesting that a single or small number of high-dose psilocybin sessions could produce significant reductions in drinking behaviour.

His 2015 pilot study published in Psychopharmacology was among the first modern controlled examinations of psilocybin for AUD, reporting significant reductions in drinking days and heavy drinking days in a small open-label sample. His team at NYU then designed and executed a landmark randomised, double-blind, placebo-controlled trial (placebo: antihistamine diphenhydramine) that was published in JAMA Psychiatry in 2022. The trial enrolled 93 participants with AUD and found that two doses of psilocybin, combined with psychotherapy, produced significantly greater reductions in heavy drinking days compared to placebo over a 32-week period, with effect sizes that were large and clinically meaningful. This represented one of the strongest designs and most convincing efficacy signals yet produced in the psychedelic addiction literature. His group is now extending this work to opioid use disorder, for which the therapeutic need is arguably even more acute given opioid-related mortality statistics.

Key publications: Bogenschutz et al. (2015, Psychopharmacology — AUD pilot); Bogenschutz et al. (2022, JAMA Psychiatry — landmark AUD RCT).

Stephen Ross

Associate Professor of Psychiatry & Director, Addictive Disorders — NYU Langone Health

Stephen Ross is a dual-board-certified psychiatrist and addiction medicine specialist who has been instrumental in advancing psilocybin research within the medical mainstream. His 2016 study, published in the Journal of Psychopharmacology simultaneously with the Johns Hopkins study by Griffiths and colleagues, administered psilocybin to cancer patients with life-threatening diagnoses who were experiencing clinically significant anxiety and depression. The results were striking: a single moderate-to-high dose of psilocybin produced rapid and sustained reductions in anxiety, depression, hopelessness, and demoralization, with effects persisting at 6.5-month follow-up in the majority of patients. A long-term follow-up (Ross et al., 2021) confirmed that a majority of participants maintained therapeutic benefits at approximately 4.5 years post-treatment.

As Director of the NYU Langone Center for Psychedelic Medicine, Ross oversees a multi-study research programme and is also heavily invested in training the next generation of psilocybin therapists. He conducts training programmes for clinicians in psilocybin-assisted therapy, emphasising the importance of the therapeutic relationship, careful preparation, and skilled integration support as determinants of outcome. His research group is also conducting studies on psilocybin for major depressive disorder, tobacco use disorder, and — in collaboration with Bogenschutz — alcohol and opioid use disorders.

Key publications: Ross et al. (2016, J Psychopharmacol — cancer anxiety); Ross et al. (2021, long-term follow-up); ongoing NYU addiction and depression trials.

Charles Grob

Professor of Psychiatry & Biobehavioral Sciences — David Geffen School of Medicine, UCLA

Charles Grob occupies a particular historical position in the modern research renaissance: his 2011 study on psilocybin for anxiety in advanced cancer patients, published in the Archives of General Psychiatry, was the first modern randomised controlled investigation of psilocybin’s therapeutic potential. Conducted at the Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, this within-subjects crossover study used an active placebo (niacin) rather than an inert substance, found significant reductions in anxiety at one and three months post-treatment, and established that psilocybin could be administered safely to a medically ill population within appropriate safeguards. It was a critical proof-of-concept study that enabled the more fully powered designs at Johns Hopkins and NYU that followed.

Grob has also conducted research on the therapeutic and cultural contexts of ayahuasca, working with members of the União do Vegetal (UDV) religious group in Brazil and the United States. This cross-cultural work reflects his broader interest in the relationship between indigenous healing traditions and contemporary psychedelic medicine — an interest he shares with researchers like Wasson in the ethnographic tradition. He edited the volume Hallucinogens: A Reader (2002, Tarcher/Putnam) and has been an important mentor and facilitator of early-career psychedelic researchers at UCLA and elsewhere.

Key publications: Grob et al. (2011, Arch Gen Psychiatry — first modern psilocybin RCT); research on ayahuasca and UDV.

Katrin Preller

Research Group Leader — University of Zurich & ETH Zurich

Katrin Preller is a neuroscientist and experimental psychologist whose research examines how psilocybin and other serotonergic psychedelics affect social cognition, emotion processing, and self-related processing. Her work bridges the detailed neuropharmacology of the Vollenweider group (within which she trained) with questions of clinical relevance for conditions characterised by social impairment or emotional dysregulation, including depression, social anxiety disorder, and autism spectrum conditions.

Her key finding, published in a series of papers using fMRI and computational modelling, is that psilocybin substantially alters the way the brain processes social signals and self-other boundaries — specifically by modulating activity and connectivity within the 5-HT2A-dense medial prefrontal cortex and the temporal-parietal junction, regions central to mentalising (understanding others’ mental states) and self-referential processing. She has shown that these changes are directly mediated by 5-HT2A receptor activation and can be reversed by pre-treatment with ketanserin. Her research on how psychedelics alter music perception and social bonding has also been influential in the therapeutic context, where music and interpersonal connection between guide and participant are considered important mediators of therapeutic outcome. She is a regular collaborator with Vollenweider and an increasingly prominent independent voice in European psychedelic neuroscience.

Research focus: Social cognition, 5-HT2A receptor mechanisms, self-referential processing, music and social bonding under psilocybin; implications for depression and autism.

Boris Heifets

Associate Professor of Anesthesiology — Stanford University School of Medicine

Boris Heifets leads one of the most mechanistically focused research programmes in psychedelic science, using rodent models to investigate the precise biological pathways through which psilocybin and related compounds produce their antidepressant-like effects. His approach involves surgical, pharmacological, and genetic manipulations that are not possible in human studies, allowing a level of mechanistic resolution unavailable from neuroimaging or clinical trial data alone.

His most controversial and discussed finding, published in Nature in 2023 with co-investigator Robert Malenka, was that psilocybin produced antidepressant-like effects in mice even when its subjective, perceptual effects were blocked by prior administration of a 5-HT2A antagonist. If replicated and translatable to humans, this would suggest that the subjective psychedelic experience — the “trip” — may not be a necessary mediator of the therapeutic effect. This is highly controversial because most clinical researchers and many patients believe the qualitative character of the experience is central to therapeutic benefit. The finding raises the possibility of developing “psychedelic-adjacent” compounds that produce neuroplasticity benefits without perceptual alterations, potentially removing barriers related to medical supervision requirements and patient acceptance. His group continues to investigate the cellular and circuit-level mechanisms of psilocybin action, particularly in relation to synaptic plasticity in prefrontal cortex.

Key publications: Heifets et al. (2023, Nature — subjective experience not required for antidepressant effect in mice); multiple mechanistic rodent studies from the Stanford group.

Gül Dölen

Associate Professor of Neuroscience — Johns Hopkins University School of Medicine (now Columbia)

Gül Dölen is a neuroscientist whose 2023 paper in Nature published one of the most conceptually significant findings in recent psychedelic science: that psychedelics — including MDMA, ibogaine, ketamine, and psilocybin — reopen “critical periods” of brain plasticity in adult mice. Critical periods are windows during development when the brain is especially sensitive to experience and capable of rapid learning and reorganisation; after these windows close, the brain becomes less plastic and more resistant to change. Dölen’s finding that psychedelics can transiently reopen such a critical period (specifically for social reward learning) provides a compelling neurobiological explanation for why the therapeutic effects of single or small numbers of psychedelic sessions can persist for months or years in humans.

The concept also has implications for timing and context: if psychedelics create a temporary window of heightened plasticity, then what happens during and immediately after a psychedelic session (the learning, the therapeutic work, the integration) may be particularly important in determining long-term outcomes. Dölen’s research on octopuses — demonstrating that MDMA produces prosocial behaviour even in this evolutionarily distant species that normally lacks the mammalian oxytocin system — has also illuminated the deep evolutionary roots of social reward circuits and suggested that the therapeutic effects of entactogens (MDMA-like compounds) may operate via more ancient and conserved mechanisms than previously recognised.

Key publications: Dölen et al. (2023, Nature — psychedelics reopen critical periods of brain plasticity); Dölen et al. (2019, octopus/MDMA social behaviour); ongoing critical period and plasticity research.