Psilocybin and Mystical Experiences: A Scientific Exploration
Psilocybin, the active hallucinogenic compound in so-called "magic mushrooms”, has become a focus of scientific research for its ability to induce mystical experiences under controlled conditions. Recent research has shown that high doses of psilocybin can trigger profound altered states that users often describe as life-altering, spiritual or mystical in nature.
Such experiences were once mainly the domain of mysticism, but modern science is now examining them in the lab, measuring their features, probing their neurological basis, and even testing their therapeutic potential.
This article by neuroscientist and researcher Tommaso Barba explores what mystical experiences are, where the concept comes from, how psilocybin can spark these states, and what research says about their benefits and limitations.
What are Mystical Experiences?
The term mystical experience refers to a specific kind of altered state of consciousness that has been described across cultures and spiritual traditions. Psychologist William James famously outlined four hallmarks of mystical experiences in The Varieties of Religious Experience (1902):
Transient: The experience is temporary, with a clear beginning and end. It feels outside ordinary time and space, and afterward one returns to normal consciousness.
Ineffable: The experience “cannot be adequately put into words”, defying expression and description. Mystics often stress that language fails to capture the depth of what was felt.
Noetic: The experiencer has a feeling of gaining profound insight or knowledge. There is a sense that some deep truth has been revealed or learned, even if it’s hard to articulate.
Passive: The experience happens to the person, beyond their deliberate control. It often involves a sense of surrender to a greater power or presence; even if one prepares via meditation or prayer, the ultimate experience feels like it comes from an outside agency.
Walter Stace and the Common Core of Mystical States
Later scholars expanded on these characteristics. Analyzing firsthand accounts from many religious traditions, philosopher Walter Stace found a common core of qualities that define mystical experiences across cultures.
In addition to James’ criteria, Stace emphasized a sense of unity (feeling “at one” with the universe or with the divine), a deeply positive mood (joy, peace, love), a sense of the sacred or holy nature of the experience, and a feeling of transcending normal time and space. In a mystical state, all feelings of separation or “otherness” may disappear, the person feels merged with a greater reality. As one description puts it, the individual discovers that he or she is not distinct from the cosmos or God, but one with it. Experiencers often describe an overwhelming sense of peace, awe, and reverence during such episodes.
The Subjective Yet Potentially Transformative Nature of Mystical States
Crucially, mystical experiences are highly subjective, they are private, interior events that can only be directly known by the person having them. However, their after-effects can sometimes be observed. People frequently report that a genuine mystical experience is transformative, bringing lasting changes in their attitudes, values, or behavior.
William James noted that although transient, these events can have a lasting impact, a sense of newfound meaning or knowledge that endures after the ecstasy fades. Modern research has borne this out: individuals often credit mystical-type experiences with boosting their life satisfaction, sense of purpose, or emotional well-being long after the fact.
How Science Studies Mystical Experiences
Because mystical experiences are spontaneous and relatively rare in everyday life, they were historically difficult to study under scientific conditions. Early psychologists and scholars had to rely on personal accounts from religious mystics, saints, and meditators.
James himself pieced together his four criteria by analyzing reports from diverse sources like Christian mystics, Sufi poets, and Buddhist practitioners. But there was no way to predictably induce a mystical experience in a laboratory, at least not until researchers turned to psychedelic substances.
The Good Friday Experiment: Early Psychedelic Research
In the 1960s, scientists began to explore whether psychedelic drugs could reliably trigger mystical-type states. In a famous 1962 experiment on Good Friday at Boston University’s Marsh Chapel (often called the “Good Friday Experiment”), 20 theology students were given a psychedelic or placebo before a church service.
Those who unknowingly received psilocybin had striking results: “Almost all” of the psilocybin group reported experiencing profound religious or mystical experiences, whereas none of the placebo (active placebo niacin) group did.
One participant, religious scholar Huston Smith, described his psilocybin-induced vision that day as “the most powerful cosmic homecoming I have ever experienced”. This early study provided empirical support for the idea that psychedelic drugs can facilitate genuine mystical experiences under the right conditions.
The study, however, was not without controversies, as further investigations showed that many subjects struggled with acute anxiety, and one had to be restrained and sedated due to the possible occurrence of a transient psychotic attack.
Measuring Mystical Experiences: The Mystical Experience Questionnaire (MEQ)
To quantify mystical experiences for research, psychologists developed standardized questionnaires. Walter Pahnke, who led the Good Friday Experiment, created one of the first surveys to rate the extent of mystical qualities in a person’s experience. Decades later, researchers at Johns Hopkins University refined these into the Mystical Experience Questionnaire (MEQ), a 30-item instrument that assesses mystical experiences across several dimensions (such as unity, transcendence of time/space, sacredness, noetic quality, positive mood, and ineffability).
The MEQ provides a validated, quantitative measure of how fully someone’s experience meets the criteria of a “complete” mystical experience. For example, questions ask to what degree the person felt a sense of unity, a loss of usual time and space, an encounter with something divine, etc., on a numerical scale.
If a person scores above a certain threshold on all the major dimensions, researchers classify it as a “complete mystical experience”. Using tools like the MEQ, scientists can compare mystical experiences across individuals and even correlate the strength of the experience with other outcomes.
Notably, the MEQ was validated using psilocybin itself. Roland Griffiths and colleagues at Johns Hopkins administered psilocybin to volunteers and confirmed that the questionnaire reliably captures the features of the induced mystical states.
This helped establish the MEQ as a standard measure in psychedelic science. In other words, psilocybin provided a research window into mysticism: by reliably occasioning mystical experiences in a lab, it allowed systematic study of their characteristics and consequences.
Clinical Research Findings on Psilocybin-Induced Mystical Experiences
Over the past two decades, a series of rigorous clinical studies have cemented the link between psilocybin and mystical-type experiences. In 2006, Roland Griffiths’ team at Johns Hopkins published a landmark double-blind trial in which spiritually active adults took either psilocybin or a placebo.
The outcomes were striking: a majority of those who received psilocybin (at a sufficiently high dose) had what the researchers classified as a “complete mystical experience,” as measured by the questionnaire. These participants commonly reported classic mystical features, unity, transcendence, ineffability, deep positive mood, etc, during their session.
Even more remarkable, when followed up 14 months later, most still ranked the psilocybin experience as one of the most personally meaningful and spiritually significant events of their entire life. Many placed it in the top five lifetime experiences, on par with the birth of a child or loss of a parent. Such lasting personal significance was almost unheard of for a single laboratory session.
The Role of Dose, Setting, and Safety in Mystical Experience Outcomes
Subsequent controlled studies reinforced these findings. Researchers found that psilocybin’s mystical effects are dose-dependent (higher doses more reliably induce full mystical states) and can be obtained safely with screening and preparation.
These effects were specific to psilocybin (as opposed to a placebo or non-hallucinogenic comparator) and were confirmed even under double-blind conditions controlling for expectations. In other words, the “mystical” outcome was not just due to hype or participant imagination; the pharmacology of psilocybin itself played a key role.
Therapeutic Implications of Psilocybin Induced Mystical Experiences
Beyond the intrinsic interest of inducing mystical states, scientists are very interested in how these experiences might be harnessed for healing. In recent years, psilocybin has been tested (in combination with psychotherapy) for treating various mental health conditions, from addiction to depression and end-of-life anxiety.
Intriguingly, across many of these studies, the occurrence of a strong mystical-type experience during the psilocybin session predicts better clinical outcomes for the patient. In other words, those who undergo a full mystical experience tend to have greater improvements in their symptoms.
The Links Between Mystical States and Better Psychedelic Therapy Outcomes
In a pilot study treating nicotine addiction, individuals who achieved a complete mystical experience with psilocybin had markedly higher success rates in quitting smoking compared to those who did not reach a mystical state. Similarly, trials in people with cancer-related depression and anxiety found that psilocybin sessions led to significant reductions in distress, and the degree of mystical experience correlated with the magnitude of anxiety/depression relief.
Scientists caution that this is a correlation (we can’t yet prove the mystical experience causes the improvement). However, the consistency of the pattern, across different studies and conditions, suggests that the mystical-quality experience might be a key mediator of psychedelics’ therapeutic effects.
Many researchers hypothesize that the profound insights or shifts in perspective that come with a mystical experience help “reframe” a patient’s mindset, making them more open to change and healing. Indeed, qualitative interviews often reveal that patients consider the mystical experience the “catalyst” for their positive life changes (such as breaking their addiction or coming to peace with mortality).
Variability in Psilocybin Induced Mystical Experiences and The Role of Preparation and Integration
It’s important to note that not everyone who takes psilocybin in these studies has a full-on mystical experience. There is significant variability; some may have more challenging psychological experiences or more moderate effects. But overall, a substantial subset do report intensely mystical feelings, and these tend to be the ones with the most striking and sustained improvements.
This has even led some experts to suggest that facilitating a mystical experience may be central to maximizing the therapeutic benefit of psychedelic-assisted therapy. Therapists now often explicitly prepare patients for the possibility of a “peak” or mystical-type experience, and integration sessions afterward focus on processing any insights gleaned during those moments of ego-dissolution and unity.
Beyond Psychedelics: Other Routes To Mystical Experience
Psychedelic drugs like psilocybin have proven to be a reliable trigger for mystical states, but they are not the only path. Mystical experiences have been reported throughout history via various religious and contemplative practices, intense meditation, prayer, fasting, chanting, and so on.
For instance, experienced meditators sometimes describe episodes of complete ego-loss and oneness with the universe during deep meditation retreats. There are also accounts of spontaneous mystical experiences occurring during near-death experiences or other extreme life events. However, such natural or spiritual avenues to mysticism tend to be unpredictable and infrequent.
By contrast, psychedelics offer a more dependable (if pharmacological) method to induce similar states, which is partly why they’ve become a research tool.
Orgasmic Meditation and Mystical Experience Research
Interestingly, recent research suggests that even some intense sexual experiences might qualify as “mystical.” A 2021 study applied the Mystical Experience Questionnaire to an practice called orgasmic meditation (OM), a partnered mindfulness technique involving 15 minutes of clitoral stimulation intended to induce a heightened state of consciousness.
The findings were surprising: across hundreds of participants, a significant fraction reported that their orgasmic meditation session met the criteria for a mystical-type experience. In one survey of 780 OM practitioners, 62% scored high enough on the MEQ30 to be classified as having a “complete mystical experience” during orgasm.
A follow-up laboratory study with paired partners found lower but still notable rates of mystical experience in both the stimulating partner and the recipient. In short, the data suggest that the OM practice, which blends aspects of sexuality and mindfulness, “can trigger a substantial mystical experience in both partners”.
The qualities reported (unity, loss of time, ineffability, etc.) closely paralleled those from psychedelic sessions. While this is a very different domain, it underlines that mystical-type experiences aren’t exclusive to drugs or spiritual retreats, they might emerge in any context that profoundly alters consciousness, even if that context is an intimate human experience.
Shared Features Across Mystical Experiences: Psychedelics, Meditation, and Sexual Practices
Comparative research has hinted that the mystical feelings from these different catalysts (psychedelics, meditation, sexual practices) share a common core.
People often describe a dissolution of the ego or usual sense of self, a merging with something greater, and a feeling of contact with a deeper reality or truth. Such similarities raise fascinating questions about the underlying neurobiology of mystical states, regardless of trigger.
The Brain on Psilocybin Induced Mystical Experiences: Clues From Neuroscience
What is happening in the brain during a psilocybin-induced mystical experience?
Modern neuroimaging studies have begun to shed light on how these transformative states arise from neural activity – and interestingly, the findings align with some theories from meditation research. One key player is the brain’s default mode network (DMN), a network of interconnected regions (including the medial prefrontal cortex and posterior cingulate cortex) that is most active during mind-wandering, self-reflection, and our normal “ego” or sense of self.
When people ingest psilocybin, activity in the default mode network tends to quiet down or desynchronize dramatically. Studies have shown that psilocybin (and related psychedelics like LSD) causes a strong decrease in connectivity within the DMN, essentially reducing the brain’s usual self-focused chatter.
At the same time, it transiently liberates other brain regions to communicate in novel ways, increasing global integration of brain networks. Some researchers describe this as a breakdown of the brain’s “default” model of reality, allowing a more fluid, unfiltered mode of consciousness.
The Default Mode Network and Ego Dissolution
The default mode network suppression is intriguing because it correlates with subjective reports of “ego-dissolution”, the feeling that one’s usual self-boundaries have dissolved, often a precursor to the sense of unity in mystical experiences.
In fact, when people report a complete mystical experience on psilocybin, fMRI scans typically show especially pronounced disruptions in the default mode network. Likewise, experienced meditators, when they attain a deep sense of no-self or unity, have been found to exhibit decreased DMN activity.
Scientists have proposed a neural model of mystical experience grounded in these changes to the DMN. As the DMN “ego-center” shuts down, the theory goes, the usual boundaries between self and world relax, making possible the intense feelings of oneness, timelessness, and connection that define mystical consciousness.
In essence, mystical experiences may emerge when the brain’s default mode network lets go of its tight grip on our perception, allowing a more unitive mode of awareness to flood in.
Debates and Criticisms on Psychedelic Mystical Experiences: A Critical Perspective
The growing evidence that psychedelics can induce mystical experiences and that these might have therapeutic value has generated excitement, but also debate.
Scientific Concerns About the Term “Mystical”
Some scholars caution against overusing the term “mystical” in a scientific context, worrying that it brings religious or supernatural connotations that could undermine scientific credibility. After all, mysticism historically links to theology and spirituality, not medicine.
A 2021 commentary titled “Moving Past Mysticism in Psychedelic Science” argued that researchers should be careful about framing results in terms of “mystical consciousness,” and instead use more neutral, “demystified” models of what psychedelics do to the brain-mind system.
The concern is that invoking mysticism might bias participants or lead to interpreting drug experiences through a religious lens, when science should remain agnostic about the ultimate nature of these experiences.
To maintain rigor, these critics suggest focusing on measurable psychological phenomena (like ego-dissolution, oceanic boundlessness, or self-transcendence) rather than labelling them outright as encounters with the divine.
Are Drug-Induced Mystical States “Authentic”?
There are also philosophical and cultural critiques. For instance, some definitions of “religious experience” would exclude drug-induced events on the grounds that they’re not situated in a traditional spiritual practice. From this perspective, taking a pill to have a mystical experience is fundamentally different from a monk achieving one after decades of meditation. The former might be seen as an artificial mimic.
Scholar Norman Habel, for example, argued that because psychedelic experiences aren’t embedded in a religious context or discipline, they shouldn’t be classified as true religious (or mystical) experiences. This view reflects a concern that the context and integration of an experience are what give it spiritual value, not just the phenomenology alone.
Alternative Predictors of Psychedelic Benefits
Another point of debate is whether the mystical experience is necessary or sufficient for the benefits of psychedelics. While correlations are strong, it’s possible that other aspects of the psychedelic experience (such as confronting emotional insights or simply the biochemical effects on neuroplasticity) also play a role in therapeutic outcomes.
Not every person who benefits from psilocybin reports a classic mystical experience; some may improve through psychological catharsis or heightened emotional processing even without feeling one with the universe. Over-emphasizing mysticism could lead to neglecting these other pathways. Researchers are actively investigating alternative outcome predictors (for example, feelings of “emotional breakthrough” or “psychological insight” during the trip) alongside mystical-unity scores.
How Psychedelic Science Navigates the Controversy Around Mystical Experiences
In summary, while the concept of mystical experience has been extremely useful for psychedelic science, it is not without controversy. Skeptics urge a balanced approach: acknowledge the profound subjective reports and their importance, but remain critical and open-minded in interpreting what they mean.
As the commentary put it, using a framework associated with “supernatural or nonempirical belief systems” carries risks, and scientists should mitigate these by careful language and a focus on data. The very word “mystical” can be polarizing, inspiring some, alienating others. Consequently, ongoing discourse in the field seeks to refine how we discuss these phenomena in a way that respects their ineffability but remains grounded in science.
Conclusion: Psilocybin, Mystical Experiences, and Human Consciousness
The intersection of psilocybin and mystical experience is a vivid example of modern science engaging with age-old questions of spirituality and consciousness. Research to date indicates that under the right conditions, a dose of psilocybin can catalyze an experience functionally identical to classical mystical experiences, complete with feelings of unity, transcendence, sacredness, and ineffability.
For many, these sessions rank among the most meaningful moments of their lives, and they have shown potential to help people break addictions, overcome depression, and cope with existential anxiety, seemingly by shifting perspectives at the deepest level.
Yet, as we have seen, this convergence of science and mysticism also raises challenging questions. What do we make of “spiritual” experiences induced by a drug? Are they neurochemical illusions or genuine windows into states of consciousness that humans have sought for millennia? The jury is still out.
What is clear is that people having these experiences, whether in a monastery or a research clinic, consistently report encounters with something beyond their ordinary self, often coming away with lasting changes for the better.
Moving forward, researchers will continue to explore not just how psilocybin induces mystical experiences (through brain networks like the DMN), but also why these states have the impacts they do. The dialogue between neuroscience, psychology, and spirituality is likely to deepen as we seek to integrate these extraordinary phenomena into our understanding of the mind.