Psilocybin mushrooms are fungi that contain the psychoactive compounds psilocybin and psilocin. There are multiple terms for psilocybin mushrooms,the most common being shrooms or magic mushrooms. The mind-altering effects of psilocybin-containing mushrooms typically last anywhere from 3 to 8 hours depending on dosage, preparation method, and personal metabolism. In 1955, Valentina and R. Gordon Wasson became the first Westerners to actively participate in an indigenous mushroom ceremony. The Wassons did much to publicize heir discovery, even publishing an article on their experiences in Life magazine in 1957. In 1956 Roger Heim identified the hallucinogenic mushroom that the Wassons had brought back from Mexico as psilocybe, and in 1958, Albert Hofmann first identified psilocin and psilocybin as the active compounds in these mushrooms.