Precision Functional Brain Mapping in Psilocybin (Psilocybin PFM)

Precision Functional Brain Mapping to Understand the Mechanisms of Psilocybin

This project will employ functional brain imaging to study the mechanism and immediate and long-term effects of psilocybin, a serotonin receptor 2A agonist, on cortical and cortico-subcortical brain networks in healthy adults.

Study Overview

• Status: Completed
• Conditions: Psilocybin
• Intervention / Treatment: Drug: Psilocybin; Drug: Methylphenidate

Detailed Description

Psilocybin shows promise as a safe, transformational therapeutic across several psychiatric conditions. However, little is know about its mechanism of action. This study aims to establish a neuroimaging paradigm for use in future clinical research testing the effectiveness of psilocybin in various clinical applications.

In this study, we will assess both acute (during psilocybin exposure) and sustained (one week post-exposure) effects of 5-HT2A receptor agonism on brain circuits using resting state functional connectivity and precision functional mapping (PFM). Using a randomized, controlled crossover study design, a small number of healthy volunteers will receive either psilocybin or methylphenidate (MTP) and will undergo MRI (structural, task, blood flow, extended resting state). After two weeks, participants will return for a second exposure with the alternate of what they received in the first session. This study involves up to five separate imaging sessions.

Functional connectivity will be measured using the following PFM approach:

1. Extended functional magnetic resonance imaging (fMRI) image acquisition
2. Aggressive data cleaning
3. Analysis designed to examine functional brain connectivity at the individual level

This will allow us to map the effects of 5-HT2A receptor agonism on cortical and cortico-subcortical brain networks at the individual level with precision that is unparalleled in the current literature. This is the first step in developing a precision neuroimaging approach for mechanistic understanding of psilocybin's therapeutic effects.

If successful, this pharmacoimaging paradigm will have potential utility across psychiatric conditions, allowing us to better understand whether and how psilocybin might "bend the curve" in treatment course, preventing persistent suffering, disability, and suicide.

• Study Type: Interventional
• Enrollment (Actual): 11
• Phase: Early Phase 1

Contacts and Locations

Study Locations

• United States
  • Missouri
    • St Louis, Missouri, United States, 63110
      • Washington University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 40 years (Adult)
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. men and woman between 18 and 40 years of age;
2. Have used a psychedelic substance within the previous 5 years but not within the last 6 months
3. No active psychiatric conditions requiring treatment with psychotropic medications (may be included if psychiatric condition is stable and participant is willing to discontinue medication for 1 month prior to participation with permission from their treating provider);
4. Able to provide informed consent.

Exclusion Criteria:

1. Presence of medical conditions that may confound results of imaging study or that are contraindications to psilocybin exposure (e.g. neurological, renal, hypertension, metabolic or cardiovascular disease or pregnancy);
2. No prior exposure to classic psychedelics (psilocybin, LSD, ayahuasca, mescaline);
3. Presence of psychiatric conditions that may confound interpretation of results or that are contraindications to psilocybin exposure (e.g. major mood disorder, current substance use disorder, personal or immediate family history (parents, siblings) of any schizophrenia spectrum disorders);
4. Use of psychotropic medication during the study;
5. Presence of contraindications to MRI scanning (implantable devices, bone hardware, IUD).
6. Prior adverse reactions to psychedelics, based on the Challenging Experiences Questionnaire administered during initial screening

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Psilocybin first; Participants will receive 25 mg of psilocybin at the first of two neuroimaging sessions, taken orally in capsule form. Participants in this arm will receive the control drug (methylphenidate) at their second drug exposure neuroimaging session.	Drug: Psilocybin; Psilocybin is a naturally occurring psychedelic compound produced by psilocybin mushrooms, and has been shown to have antidepressant and anti-anxiety effects after one dose of 25 mg. Common side effects are slight elevations in blood pressure and heart rate. Participants will be randomized to receive either psilocybin or control at two separate imaging timepoints in this study.; Other Names: psilocin; Drug: Methylphenidate; Methylphenidate is a stimulant medication used to treat attention deficit hyperactivity disorder (ADHD) and narcolepsy, and is used as an active control for this study because it is metabolized similarly to psilocybin and has similar effects on heart rate and blood pressure. Participants will be randomized to receive either psilocybin or control at two separate imaging timepoints in this study.; Other Names: Metadate, Methylin, Ritalin, Concerta
Active Comparator: Methylphenidate first; Participants in this group will be randomized to receive 40 mg of methylphenidate at the first of two neuroimaging sessions, taken orally in capsule form. Participants in this arm will receive the active comparator (psilocybin) at their second drug exposure neuroimaging session.	Drug: Psilocybin; Psilocybin is a naturally occurring psychedelic compound produced by psilocybin mushrooms, and has been shown to have antidepressant and anti-anxiety effects after one dose of 25 mg. Common side effects are slight elevations in blood pressure and heart rate. Participants will be randomized to receive either psilocybin or control at two separate imaging timepoints in this study.; Other Names: psilocin; Drug: Methylphenidate; Methylphenidate is a stimulant medication used to treat attention deficit hyperactivity disorder (ADHD) and narcolepsy, and is used as an active control for this study because it is metabolized similarly to psilocybin and has similar effects on heart rate and blood pressure. Participants will be randomized to receive either psilocybin or control at two separate imaging timepoints in this study.; Other Names: Metadate, Methylin, Ritalin, Concerta

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Functional Connectivity	Our overall goal is to use a Functional Connectivity (very long scans to produce individual connectomes) to examine the effects of psilocybin on cortical and cortico- subcortical brain networks that could explain its rapid and sustained behavioral effects.	1 week

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mystical Experiences	Measured using Persisting Effects Questionnaire	1 week
Personality Change	Measured using International Personality Item Pool-Five-Factor Model	1 week

Collaborators and Investigators

• Sponsor: Washington University School of Medicine

Study record dates

Study Major Dates

• Study Start (Actual): June 1, 2021
• Primary Completion (Actual): March 19, 2023
• Study Completion (Actual): March 19, 2023

Study Registration Dates

• First Submitted: August 3, 2020
• First Submitted That Met QC Criteria: August 3, 2020
• First Posted (Actual): August 6, 2020

Study Record Updates

• Last Update Posted (Estimated): October 31, 2025
• Last Update Submitted That Met QC Criteria: October 29, 2025
• Last Verified: October 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Organic Chemicals; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Heterocyclic Compounds, 2-Ring; Heterocyclic Compounds, Fused-Ring; Carboxylic Acids; Alkaloids; Piperidines; Indoles; Indole Alkaloids; Indolizidines; Indolizines; Acids, Carbocyclic; Tryptamines; Phenylacetates; Methylphenidate; Psilocybin; psilocin
• Other Study ID Numbers: 202002165; GF0010787 (Other Identifier: Washington University)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No