The Nahua word recorded by the Spanish was teonanacatl, ordinarily rendered as flesh of the gods, and it named mushrooms eaten at feasts to produce visions. Bernardino de Sahagun's informants described their use, and the friars catalogued the practice in order to end it, treating it as an obstacle to conversion rather than as an object of study.
It survived, quietly, in the Sierra Mazateca of Oaxaca and in neighbouring highland communities, where it was folded into a Catholic surface that made it survivable. The ceremony is the velada, a vigil: it runs through the night in darkness, the mushrooms are eaten in pairs, and it is led by a healer who sings almost continuously. The singing is again not decoration. The songs name saints, Christ, the earth, and the mushrooms themselves, and the healer speaks as much for the mushrooms as to them.
The purpose is not experience. A velada is held for a reason, most often a sickness that has not resolved or a question about a person or an event, and the patient and the healer take the mushrooms together so that the healer can see what is wrong. The idea of taking them for their own sake, without a question and without a healer, has no place in the tradition and would have made little sense inside it.