Vincent Verroust

Psychedelic Science Consultant, Science Historian, Ethnobiologist,
Lead Coordinator of the French Psychedelic Society


"Will you give me again some of these mushrooms, doctor?" the experiments of Heim and Thévenard on healthy volunteers, Paris, 1959

Talk date & time:
Friday 15:00-16:00


Professor Roger Heim (1900 - 1979) was invited by the Wassons to participate in the multidisciplinary study of the Mexican divinatory mushrooms rediscovered in the early 1950s. He identified or described and named the species collected, developed their cultivation and enabled Albert Hofmann and his colleagues to isolate psilocybin and psilocin. After conducting experiments on himself, he worked on a documentary film on the hallucinogenic mushrooms in collaboration with Dr Thévenard of the Pasteur Institute. Vincent Verroust has recovered the film and proposes to screen and comment on the experiments carried out on healthy volunteers who agreed to consume Psilocybes mexicana in front of a camera, in Paris, in 1959, with a follow-up four years later. The filmed sequences illustrate the diversity of psychological reactions to psilocybin mushrooms as well as their medical, scientific and philosophical interest.


Vincent Verroust is a PhD candidate in the history of sciences at the Centre Alexandre-Koyré (Paris), an associate researcher at the Institut des humanités en médecine (Lausanne), and a consultant at the Paul Brousse hospital for the resumption of clinical trials with controlled substances. He is also a teacher and a founding member of the French psychedelic society. His investigations focus on the discovery of psilocybin fungi and the naturalization of a psychological experience.