Dennis McKenna, an ethnopharmacologist, research pharmacognosist, lecturer & author of The Brotherhood of the Screaming Abyss about his and his brother Terence's life and journeys together. His brother Terence McKenna is well-known psychedelics proponent.

Dennis is also the founding board member and the director of ethnopharmacology at the Heffter Research Institute, a non-profit organization concerned with the investigation of the potential therapeutic uses of psychedelic medicines.

Also Check out his new project called The McKenna Academy (www.McKenna.Academy).

Dennis has also been in two great documentaries worth checking out, Neurons to Nirvana: Understanding Psychedelic Medicines, and DMT: The Spirit Molecule.