state of consciousness altered state of consciousness http://id.loc.gov/authorities/subjects/sh89006368 http://purl.bioontology.org/ontology/MEDDRA/10001854 https://en.wikipedia.org/wiki/Altered_state_of_consciousness https://www.wikidata.org/wiki/Q852859 ASC BF1045.A48 Any condition considered significantly different from a normal waking state. The term "altered state of consciousness" (ASC) as an expression has been used in many different circumstances, both scientific and pseudoscientific. By 1892, the expression was in use in relation to hypnosis although an ongoing debate about hypnosis as an ASC based on modern definition exists. The next retrievable instance, by Dr. Max Mailhouse from his 1904 presentation to conference, however, is unequivocally identified as such, as it was in relation to epilepsy, and is still used today. In academia, the expression was used as early as 1966 by Arnold M. Ludwig and brought into common usage from 1969 by Charles Tart. It describes induced changes in one's mental state, almost always temporary. altered state of mind altered states of consciousness