Psychedelic experience sources of some psychedelic drugs such as ayahuasca and mescaline-containing cacti are sometimes referred to as "plant teachers". Similarly, in a follow-up to the psilocybin and mysticism study at Johns Hopkins, researchers observed that psilocybin: "occasions personally and spiritually significant mystical experiences that predict long-term changes in behaviors, attitudes and values". Psychedelic experience includes the full range of mystical or religious experiential phenomena. Two scientific studies have concluded that psilocybin (a typical psychedelic compound that occurs naturally in psilocybin mushrooms) reliably triggers mystical-type experiences. The more recent study at Johns Hopkins University identified mystical experiences by means of several questionnaires
Mescaline so contemporary users will often grind it into a powder and pour it in capsules to avoid having to taste it. The usual human dosage is 200–400 milligrams of mescaline sulfate or 178–356 milligrams of mescaline hydrochloride. The average button contains about 25 mg mescaline. Mescaline was first isolated and identified in 1897 by the German chemist Arthur Heffter and first synthesized in 1918 by Ernst Späth. In 1955, English politician Christopher Mayhew took part in an experiment for BBC's "Panorama", in which he ingested 400 mg of mescaline under the supervision of psychiatrist Humphry Osmond. Though the recording was