The Effects of Psilocybin on Shared Experience in Film Processing

The goal of this clinical trial is to learn whether certain methods of detecting awareness in vegetative or minimally conscious patients (using neuroimaging) are sensitive to the effects of psilocybin (a psychedelic drug). One of these methods includes scanning peoples\' brains while they watch a film. When different individuals watch a film, their brains become synchronized with each other as they watch the plot unfold. Most importantly, if a seemingly unconscious patient also shows the same brain-synchronization, it means they might actually be conscious and aware.

To approach this goal, the investigators will be carrying out this trial in healthy volunteers. This will help better understand whether psilocybin may be a potential treatment for restoring awareness in these patients. The main questions it aims to answer are:

* Does psilocybin enhance or diminish brain synchrony during a film? * Do changes in brain synchrony reflect differences in each individual\'s conscious experience?

Participants will be asked to:

* Attend two brain scanning sessions and watch a series of film clips, perform a brief mental imagery task, and listen to music - once under a placebo, and once under psilocybin. * Play a series of games that assess their cognition (memory, reasoning, planning, etc.). * Perform a series of visual illusions tasks.