Does Serotonin System Stimulation Increase Pro-social Behavior? – A Comparative Pharmacological Neuroscientific Study in Healthy Humans

This Phase I intervention trial (n=120) investigates whether stimulating the serotonin system influences pro-social behaviour compared to stimulating the dopamine system in healthy individuals.

Conducted by the University of Zurich, the study aims to determine if administering psychedelic substances like MDMA, psilocybin, and methylphenidate induces lasting effects on pro-social behaviour.

The trial involves administering single doses of these substances to participants and assessing their pro-social cognition using various measures, including the Multifaceted Empathy Test, Moral Inference Task, Zurich Prosocial Game, Social Gaze Task, Moral Expansion Task, Social Network Questionnaire, Pro-social Voting Behaviour scale, Oxford Utilitarianism Scale, Compassion Scale, and Inclusion of Others in the Self scale.

Additionally, subjective experiences of altered states of consciousness are evaluated using the 5-Dimensional Altered States of Consciousness Rating Scale, Mystical Experience Questionnaire, Persisting Effects Questionnaire, Epistemic and Personal Transformation questionnaire, Symptom Checklist 90-R, Positive and Negative Affect Schedule, FEELINGS scales, and Ego Consciousness Change of Perspective Questionnaire.

The trial commenced in October 2023 and is estimated to be completed by June 2025. Participants must be healthy adults aged 18-40 and meet specific inclusion criteria. The study employs a randomised, double-blind, parallel-group design, with interventions including psilocybin, MDMA, and methylphenidate.

The primary outcome measures include various tasks assessing pro-social cognition, while secondary outcome measures evaluate subjective experiences and psychological symptoms. The study aims to provide insights into the neuropharmacological mechanisms underlying pro-social effects of psychedelic substances.

Topic Healthy Subjects
Compound MDMA Psilocybin
Country Switzerland
Visit trial
Status Recruiting
Results Published No
Start date 24 October 2023
End date 30 June 2025
Phase Phase I
Design Blinded
Type Interventional
Generation First
Participants 119
Sex All
Age 18- 40
Therapy No

Trial Details

The study looks into whether administering psychedelic substances that stimulate the serotonin system influences pro-social behavior when compared to administering substances that stimulate the dopamine system in healthy individuals.

NCT Number NCT06081179

Sponsors & Collaborators

University of Zurich
Within the Department of Psychiatry, Psychotherapy and Psychosomatics at the University of Zurich, Dr Mialn Scheidegger is leading team conducting psychedelic research and therapy development.

Data attribution

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