This is an observational study which does NOT directly administer a psychedelic substance but rather recruits participants who are already participating in another clinical trial in which they may receive a serotonergic psychedelic. The goal of this observational study is to learn how the brain's information processing changes during and following administration of serotonergic psychedelics (psilocybin, N,N-Dimethyltryptamine/DMT, Lystergic Acid Diethylamide/LSD, etc.) for people with and without mental illness receiving serotonergic psychedelics through any clinical trial at Yale University. The main questions it aims to answer are: 1. Do serotonergic psychedelics cause the brain to rely on new information more than previously learned information while under the influence? What about 1 day, 5-14 days, and 4-6 weeks after use? 2. Do serotonergic psychedelics cause long-lasting side-effects in how people perceive (see, hear, feel, etc.) the world and how easily people change their beliefs? 3. How does the brain's electrical activity change after using serotonergic psychedelics? How does the balance between excitation and inhibition change while under their effect? 4. Can changes in how the brain uses information predict who will benefit from a psychedelic and who will have side effects from psychedelics? Researchers will compare with people given placebos to see what changes in brain processing are unique to serotonergic psychedelics. Participants will have the opportunity to do some combination of the following: 1. Online computer assessments consisting of games and questionnaires that probe how participants think. 2. Magnetoencephalography (MEG) or electroencephalography (EEG) with eyes closed and with repeated clicks, images, or sensations delivered. 3. A magnetic resonance imaging (MRI) scan. 4. Semi-structured qualitative interviews about their experience after taking a serotonergic psychedelic recorded via Zoom.
Age range
18 Years – 65 Years
Sex
ALL
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AI-rewrites the medical criteria so a patient or caregiver can understand them. Always confirm with the trial site.
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Generated to help you prepare — always confirm anything about your own eligibility and care with the study team and your doctor.
The trial coordinator is the person who runs the study day to day. These cover the practical side — logistics, costs, and what taking part would actually mean for your life. The study team confirms whether you meet the criteria; these are questions to ask, not a sign you qualify.
A starting point for the conversation — always confirm anything about your own eligibility, costs, and care with the study team and your doctor.
Hierarchial Gaussian Filter (HGF)-estimated average precision-weighted prediction error change in the conditioned hallucinations and probabilistic reversal learning tasks
Timeframe: Immediately post drug administration (when psychologically acceptable), 1 day post drug administration, 5-14 days post drug administration, and 4-6 weeks post drug administration
Auditory and visual conditioned hallucination rate change
Timeframe: Immediately post drug administration (when psychologically acceptable), 1 day post drug administration, 5-14 days post drug administration, and 4-6 weeks post drug administration
Perseverative and jumping-to-conclusion error total change in probabilistic reversal learning task
Timeframe: Immediately post drug administration (when psychologically acceptable), 1 day post drug administration, 5-14 days post drug administration, and 4-6 weeks post drug administration
Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q) score change
Timeframe: 1 day post drug administration, 5-14 days post drug administration, and 4-6 weeks post drug administration
Southampton Mindfulness Questionnaire (SMQ) score change
Timeframe: 1 day post drug administration, 5-14 days post drug administration, and 4-6 weeks post drug administration
HGF-estimated ratio of perceptual belief-to-sensory evidence weighting change
Timeframe: Immediately post drug administration (when psychologically acceptable), 1 day post drug administration, 5-14 days post drug administration, and 4-6 weeks post drug administration
Aberrant Salience Inventory (ASI) score change
Timeframe: 1 day post drug administration, 5-14 days post drug administration, and 4-6 weeks post drug administration
Change in the exponent of the 1/f power spectrum law from resting state EEG
Timeframe: Period of peak drug effect and 1 day after drug administration
Change in resting state delta, alpha, theta, low gamma, medium gamma, and high gamma bands
Timeframe: Period of peak drug effect and 1 day after drug administration