Imperial College London
Centre for Psychedelic Research
“Trial of Psilocybin versus Escitalopram for Depression”
Carhart-Harris RL, Giribaldi B, Watts R, et al.
New England Journal of Medicine · 2021
The science
The science behind psychedelic transformation.
Peer-reviewed psilocybin and ayahuasca research from Imperial College, Johns Hopkins, and MAPS, translated into a retreat protocol you can read in plain English.
Pexels · Anna Shvets
The three pillars
How healing happens.
Three forces work together. Removing any one makes the other two less durable.
Pillar 1, Pharmacology
What the molecule does
Psilocybin binds 5-HT2A receptors in cortical neurons, increasing global functional connectivity and elevating BDNF, the protein that builds new synapses. The window of plasticity lasts 2–6 weeks.
Pexels · Edward Jenner
Pillar 2, Set & setting
What the conditions create
Mindset entering ceremony and the safety of the container determine the quality of the experience. Decades of research, Leary, Pahnke, Carhart-Harris, confirm that environment is not optional, it's load-bearing.
Pexels · Pixabay
Pillar 3, Integration
What the work makes durable
The plasticity window closes within weeks. What you practice, IFS parts work, somatic regulation, journaling, community accountability, is what gets written into the new wiring. Insight without action evaporates.
Pexels · Cottonbro Studio
Pexels · Anna Shvets
The default mode network
The brain's self-narrating engine.
The default mode network is a cluster of midline brain regions — medial prefrontal cortex, posterior cingulate, precuneus — that activates when you are not focused on a task. It is the source of the running inner monologue, autobiographical memory, and self-referential thought.
In depression, anxiety, and chronic rumination, the DMN is hyperactive and rigid. fMRI studies from Imperial College London show that psilocybin temporarily reduces DMN activity and increases communication between brain networks that normally do not interact — measured as a rise in global functional connectivity and a decrease in modular segregation.
The lived experience: rumination softens, ego boundaries become porous, and stuck patterns become visible from a vantage point outside the usual self-story. The window closes within hours, but what was seen from outside often cannot be unseen.
Psychedelics shake the snow globe. The molecule itself doesn't fix anything, it loosens what was rigid, and then it's up to the conditions, the support, and what you practice in the weeks that follow to determine whether the new pattern sets.
Robin Carhart-Harris, PhD
Founding Director, Centre for Psychedelic Research, Imperial College London
Neuroplasticity
The window where new wiring forms.
Ly et al. (Cell Reports, 2018) showed that classical psychedelics increase dendritic spine density and synaptic signaling in cortical neurons within 24 hours of a single dose. The effect is mediated by 5-HT2A receptor activation and a surge in BDNF — brain-derived neurotrophic factor, the molecule that builds new synapses.
Behaviorally, this is the “plasticity window.” Habits that took decades to form become unusually editable. Trauma responses can be re-coded. New self-narratives can take root with less resistance than usual. The rat literature shows the structural changes peak around 24 hours; the human phenomenology suggests the lived window of integration runs roughly two to six weeks.
The implication is practical, not magical. The molecule does not install change — it makes change cheaper. What you practice during the window is what gets written. This is why Ceremonia treats integration as load-bearing, not aftercare.
Pexels · Edward Jenner
The mystical-type experience appears to be a key mediator of the therapeutic effect. The depth of personal meaning and the felt sense of unity people report do not seem incidental, they correlate with the magnitude and durability of clinical improvement.
Roland R. Griffiths, PhD
Founding Director, Center for Psychedelic & Consciousness Research, Johns Hopkins Medicine
Modality comparison
Three medicines. Different doors.
Same underlying pharmacology — partial 5-HT2A agonism — but the phenomenology, time course, and integration demand vary considerably. Choosing the right modality for a given person is its own discipline.
The most studied
Psilocybin
- Mechanism
- Prodrug for psilocin. Partial agonist at 5-HT2A. Quiets the default mode network and elevates BDNF and dendritic spine density.
- Clinical evidence
- FDA Breakthrough Therapy designation. Phase 2 / 3 trials at Imperial, Johns Hopkins, Compass Pathways. 71% clinical response rate in TRD (Davis et al., 2021).
- Typical experience
- 4–6 hour journey. Vivid imagery, ego softening, autobiographical insight. Body load typically light to moderate.
DMT + harmala MAOIs
Ayahuasca
- Mechanism
- DMT (5-HT2A agonist) made orally active by beta-carboline MAOIs in B. caapi. Distinctive activation of limbic and visual cortex networks.
- Clinical evidence
- Palhano-Fontes et al. (Psychol Med 2019): single-dose ayahuasca produced rapid antidepressant effects in TRD. Long observational record from Brazilian church studies.
- Typical experience
- 4–6 hour ceremony. Strong somatic and visionary content; purga (purge) is common and integral. Intensely embodied.
Brief, non-dual
5-MeO-DMT
- Mechanism
- Endogenous tryptamine. Strong 5-HT1A and 5-HT2A activity. Triggers a short, often non-dual altered state with reduced narrative content.
- Clinical evidence
- Early-stage trials (Beckley Psytech, GH Research). Reckweg et al. (2021) characterized tolerability and phenomenology in a controlled setting.
- Typical experience
- 10–30 minutes. Frequently non-dual: dissolution of subject/object boundary. Minimal visual content; high integration demand afterward.
How we cite
Every clinical claim on this page is sourced. Click any citation to read the original paper. If a study is paywalled, the DOI is the permanent identifier — it will resolve at any institutional library you have access to.
We do not paraphrase results to make them friendlier. If a number is here, it appeared in a peer-reviewed publication. If a mechanism is described, the underlying study is one click away.
Browse the full research library →The research
Where the evidence comes from.
Three flagship trials. Public DOIs. Read them yourself.
Johns Hopkins Medicine
Center for Psychedelic & Consciousness Research
“Psilocybin produces substantial and sustained decreases in depression and anxiety in patients with life-threatening cancer”
Griffiths RR, Johnson MW, Carducci MA, et al.
Journal of Psychopharmacology · 2016
MAPS Public Benefit Corporation
Multidisciplinary Association for Psychedelic Studies
“MDMA-assisted therapy for severe PTSD: a randomised, double-blind, placebo-controlled phase 3 study”
Mitchell JM, Bogenschutz M, Lilienstein A, et al.
Nature Medicine · 2021
The medicine is a catalyst. What heals is the trust between the participant and the therapy team, and the willingness to stay present with what arises. We are not curing trauma with a molecule, we are making it possible to do the work.
Michael C. Mithoefer, MD
Senior Medical Director (former), MAPS Public Benefit Corporation
What's in trial
The active registry.
A snapshot of the late-stage trials moving toward regulatory review. Sourced from ClinicalTrials.gov and sponsor disclosures; verify current status before citing.
Compass Pathways
COMP360 (synthetic psilocybin, 25 mg)
Treatment-resistant depression
Phase 3Enrolling
Primary readout expected late 2026
Lykos Therapeutics (MAPS PBC)
MDMA-assisted therapy
Severe PTSD
Phase 3 completeUnder FDA review
Resubmission planned 2026 following August 2024 CRL
Usona Institute
Psilocybin
Major depressive disorder
Phase 2Active
NCT04489862 — Phase 3 design in development
Beckley Psytech
BPL-003 (5-MeO-DMT)
Treatment-resistant depression
Phase 2bOpen-label extension
Topline 2026; partnered with atai Life Sciences
How it works
What happens in the brain.
Default Mode Network softens
Psilocybin temporarily quiets the brain's self-referential narrator, the source of rumination, opening space for new perspectives.
Functional connectivity rises
Brain regions that don't normally talk to each other start communicating, producing the felt-sense of connection and insight.
BDNF + neuroplasticity surge
Brain-derived neurotrophic factor builds new synapses; structural plasticity peaks in the first 24 hours post-dose.
Window of integration
Heightened plasticity persists 2–6 weeks. What you practice during this window, somatic regulation, IFS, community, gets encoded.
The outcomes
71%
Clinical response rate
Davis et al., JAMA Psychiatry 2021
2×
Faster than SSRIs
Carhart-Harris et al., NEJM 2021
6mo
Effect from one dose
Griffiths et al., J Psychopharmacol 2016
0
Severe adverse events
Phase 2/3 supervised trials
Full citations: see published studies below.
Frequently asked, briefly answered
Is psychedelic therapy evidence-based?
Yes. Modern psychedelic therapy is grounded in peer-reviewed neuroscience and has produced positive Phase 2 and Phase 3 results at Imperial College London, Johns Hopkins University, NYU Langone, and MAPS. Three short reasons why that matters:
Peer-reviewed
Every clinical claim on this page links to a study published in a peer-reviewed journal. Editorial review and statistical scrutiny precede publication.
Replicated
The DMN-quieting effect, the BDNF / plasticity surge, and the durability of single-dose treatment have been replicated across at least three independent research groups.
Regulated
Psilocybin holds FDA Breakthrough Therapy designation for treatment-resistant depression. MDMA-assisted therapy completed Phase 3 trials. These are not anecdotal claims.
Frequently asked
The questions people search for.
Is psychedelic therapy FDA approved?
Not yet for general practice. Psilocybin holds FDA Breakthrough Therapy designation for treatment-resistant depression (Compass Pathways, Usona). MDMA-assisted therapy completed Phase 3 trials with Lykos / MAPS PBC and is under FDA review. Esketamine (Spravato), a dissociative related to ketamine, is FDA-approved for treatment-resistant depression.How do psychedelics work in the brain?
Classical psychedelics (psilocybin, LSD, DMT) are partial agonists at the 5-HT2A serotonin receptor on cortical pyramidal neurons. This temporarily reduces activity in the default mode network, increases functional connectivity between brain regions that don't normally communicate, and triggers a surge in BDNF and dendritic spine density (Ly et al., Cell Reports 2018).Can psychedelics help with PTSD?
Phase 3 trials of MDMA-assisted therapy showed roughly two-thirds of severe PTSD participants no longer met diagnostic criteria after three sessions paired with structured therapy (Mitchell et al., Nature Medicine 2021; DOI 10.1038/s41591-021-01336-3). Results have not yet translated into FDA approval — the agency issued a Complete Response Letter in 2024.Are psychedelics addictive?
Classical psychedelics (psilocybin, LSD, DMT, mescaline) are not considered chemically addictive. Tolerance develops rapidly within 24 hours, which discourages repeated dosing. Nutt et al. (Lancet 2010) ranked psilocybin lowest in addiction potential among 20 commonly used drugs. They are not benign — they amplify whatever you bring, which is why preparation and integration matter.What is microdosing?
Sub-perceptual dosing — typically 1/10 to 1/20 of a ceremonial dose, taken on a schedule (often three days on, two off). Reported benefits include improved mood and focus, but placebo-controlled studies (Szigeti et al., eLife 2021) suggest much of the effect is expectancy. Microdosing is not what Ceremonia practices; we work with full-dose ceremonial protocols.What is the difference between psilocybin and LSD?
Both are partial 5-HT2A agonists with overlapping subjective effects. Psilocybin lasts 4–6 hours; LSD lasts 8–12. LSD has higher affinity for dopamine receptors and a longer body load. Most modern clinical trials use psilocybin because the shorter duration is logistically more practical and the molecule is found endogenously in fungi.What is set and setting?
Set is the participant's mindset — preparation, intention, current emotional state. Setting is the external container — physical space, music, the people present, and the trust relationship with facilitators. Decades of research (Leary, Pahnke, Carhart-Harris) confirm that set and setting are not mood lighting; they materially shape outcomes.What is integration after a psychedelic experience?
The structured practice of translating ceremony insight into daily life. The plasticity window after a single dose lasts roughly two to six weeks. What you practice during that window — somatic regulation, IFS parts work, journaling, community accountability — is what gets encoded. Ceremonia treats integration as load-bearing, not aftercare.How long do psychedelic effects last?
Acute effects: psilocybin 4–6 hours, ayahuasca 4–6 hours, LSD 8–12 hours, 5-MeO-DMT 10–30 minutes. Persistent effects on depression, anxiety, and well-being have been measured 6 months to 4 years out from a single supervised dose (Griffiths et al., J Psychopharmacol 2016 and 2018 follow-up).Are there people who shouldn't take psychedelics?
Yes. Personal or first-degree-relative history of psychosis, schizophrenia, or bipolar I is the strongest contraindication. Active SSRIs, MAOIs, and lithium interact with serotonergic psychedelics. Cardiac conditions and some other medical conditions require clearance. Ceremonia screens for all of these before accepting any participant; see /safety for the full protocol.
Go deeper
Browse 12 deep-dive science pages.
Pharmacology, neuroscience, psychology, frameworks, written for curious participants and clinical professionals alike.
Explore the full library
Pharmacology
Psilocybin Research
Clinical evidence from Johns Hopkins, Imperial College, and FDA Breakthrough Therapy trials.
Neuroscience
The Default Mode Network
Your brain's self-referential storytelling engine, and how psilocybin temporarily quiets it.
Neuroscience
Neuroplasticity
The brain's window of rewiring after psilocybin, and why the weeks after ceremony matter most.
Psychology
Internal Family Systems
IFS maps the inner world as a system of parts, how ceremony insights become lasting change.
Psychology
Trauma-Informed Care
Why trauma history changes everything in psychedelic work, window of tolerance, nervous-system safety.
Psychology
Somatic Experiencing
Trauma lives in the body. SE teaches the nervous system to complete interrupted stress responses.
Psychology
Mindfulness & ACT
Acceptance and Commitment Therapy, the cognitive framework for integrating ceremony insights.
Pharmacology
Ayahuasca Research
DMT, beta-carboline MAOIs, and the distinctive somatic / visionary signature of ayahuasca.
Framework
Circling
A structured relational practice: the community container for integration.
Framework
The Three Pathways
Mind, body, spirit, Ceremonia's integration framework. Sustainable change requires all three.
Framework
Map of Consciousness
David Hawkins' calibrated scale, how Ceremonia frames the arc of healing.
Framework
Research Library
Curated peer-reviewed studies, Imperial College, Johns Hopkins, MAPS. Searchable reference.
Begin
Ready to apply this to your life?
The science is compelling. The real question is whether you're ready to do the work, and we built a 5-minute readiness quiz to help you find out.