Kykeon is beer brewed from Barley which contains Ergot (LSD) (http://en.wikipedia.org/wiki/Kykeon) and was used during Eleusinian Mysteries (http://en.wikipedia.org/wiki/Eleusinian_Mysteries#Entheogenic_theories).
Sensory deprivation (light, sound, touch etc) (experienced as warmth and moving wind) taste was also used in the initiations. Sensory deprivation is, more accurately, no contrast of sensations over time i.e. a steady temperature, a steady light, a steady noise etc experienced by a person over time. No contrast means no ability to discern a thing, because there is nothing to contrast it with. Thus no sensation of a thing is a form of (or equivalent to) sensory deprivation. The psychotropic is then consumed and facilitates/enables some kind of turbulence in the calm mind. A chaotic state. In this state the only sentiments present are those that the individual took with them: both their character/personality and their current state of mind. Thus if the individual consumed the psychotropic has an aggressive character, and took a fearful state of mind with them, then they will be more likely to experience a terrifying scenario than someone who is of a jovial character who would probably have an experience more in line with their own temperament.