Brain Activity Effects of Psychedelic Medicines in Healthy Volunteers

This interventional trial (n=0, withdrawn) aimed to investigate the brain activity effects of psychedelic medicines, specifically psilocybin or MDMA, in healthy volunteers.

The trial was initiated to understand changes in neural activity associated with a single session of psychedelic drug exposure, utilising electroencephalography (EEG) measurements taken before and after exposure. Participants were to undergo a single drug exposure session, either individually or in small groups, with support from two therapists.

The primary outcomes included EEG measures such as N100 and N170 obtained during various tasks, alongside secondary outcomes covering personality, side effects, trust, mindfulness, and metaphysical beliefs.

The trial’s design involved non-randomised allocation, and while it was planned to recruit participants until August 2025, the recruitment was later withdrawn due to a lack of funding, staff, or facilities.

The study was funded by Transcranial Magnetic Stimulation Clinics Australia and Mind Medicine Australia and was conducted under the leadership of Dr Neil Bailey. The data sharing statement indicated that both EEG data and self-report data would be made available to the public, with individual participant data being shared three months after the main results publication, with no specified end date.

Trial Details

The objective of this project is to investigate changes in neural activity associated with a single session of psychedelic drug exposure, in particular with psilocybin or 3,4- methylenedioxymethamphetamine (MDMA). Specifically, the study aims to use electroencephalography (EEG) to measure neural activity both before and two weeks after psychedelic exposure. EEG activity during a latent inhibition task will be measured, as decreased latent inhibition has been associated with the personality trait of openness to experience, a trait which previous research has shown is increased by exposure to psychedelics. Similarly, EEG activity during an auditory oddball task will be measured, as previous research has shown that exposure to psychedelics reduces neural adaptation to familiar stimuli. Neural activity associated with processing of facial emotions will also be assessed, as this activity has been suggested to be modified by MDMA and could be a potential explanation for therapeutic effects. Additionally, resting EEG measures will be used to test whether psychedelic exposure is associated with changes to the excitation/inhibition balances that underpinning healthy neural activity. We hypothesize that the measures of neural activity listed above will differ from pre to post psychedelic exposure. Since both psilocybin and MDMA are becoming more commonly used to treat psychiatric illnesses, this study is important to both improve our understanding of the potential mechanisms of action of these drugs. As such, this study will have the potential to be highly beneficial in improving our understanding of these drugs as they transition towards broad scale implementation as therapies for psychiatric conditions.

NCT Number ACTRN12622000883718p

Data attribution

A large set of the trials in our database are sourced from ClinicalTrials.gov (CTG). We have modified these post to display the information in a more clear format or to correct spelling mistakes. Our database in actively updated and may show a different status (e.g. completed) if we have knowledge of this update (e.g. a published paper on the study) which isn't reflected yet on CTG. If a trial is not sourced from CTG, this is indicated on this page and you can follow the link to the alternative source of information.