Altered State(s) of Consciousness (ASC): Expression popularized by Charles T. Tart which can refer to virtually any mental state differing from that of the normal waking condition; of parapsychological interest as possibly psi-conducive states; they include dreaming, hypnosis, trance, meditation of the yoga or Zen tradition, the hypnagogic-like state induced by the ganzfeld, and drug-induced states.

References

1. Parapsychology by Michael A. Thalbourne, Republished by Puente Publications, Charlottesville, VA, USA, 2003