Altered state of consciousness
An altered state of consciousness (ASC), also called altered state of mind or mind alteration, is any condition which is significantly different from a normal waking beta wave state. By 1892, the expression was in use in relation to hypnosis but likely does not accord to the modern definition of ASC (see Concept). The next retrievable instance, by Dr Max Mailhouse from his 1904 presentation to conference, does however, as it was in relation to epilepsy, and is still used today (see Epilepsy). 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. A synonymous phrase is "altered state of awareness".
An altered state of consciousness is any mental state induced by physiological, psychological, or pharmacological maneuvers or agents, which deviates from the normal waking state of consciousness.
Revonsuo, Kallio, & Sikka (2009) arrived at three definitions,
What seems to be in common with these definitions is that there has to be a change in the content of consciousness (change in primary phenomenal consciousness) and at least an implicit assumption that the person being in an ASC should somehow recognize this and be able to give introspective reports about it (involvement of reflective consciousness) […] Thus, we arrive at three potential definitions of an ASC:
Definition 1.1: ASC as a state in primary phenomenal consciousness. ASC is defined by the changed (overall) pattern of subjective experience in primary phenomenal consciousness.
Definition 1.2: ASC is a phenomenal state in primary phenomenal consciousness and the corresponding cognitive state in reflective consciousness. ASC is defined by the changed (overall) pattern of subjective experience in primary phenomenal consciousness, coupled with the cognitive recognition of the change at the level of reflective consciousness, and classification of the experience as altered.
Definition 1.3: ASC is a psychological state and a neural state. ASC is defined as above in 1 or 2, but in addition to that, a corresponding altered pattern of neural activity must be involved and objectively detected.
Some observable abnormal and sluggish behaviors meet the criteria for altered state of consciousness. Altered states of consciousness can also be associated with artistic creativity or different focus levels. They also can be shared interpersonally and studied as a subject of sociological research.
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