Felicitas Goodman (1990) observed that naive participants experienced unique trance states, characterized by specific visionary content, when they assumed particular postures and listened to monotonous rattling. Students (n = 284), enrolled in various sections of the course Introduction to Psychology, experienced one of four conditions with their eyes closed: Sitting Quietly with and without Drumming, Standing (Feather Serpent) Posture plus Drumming with and without Suggested Experiences. Participants completed the Phenomenology of Consciousness Inventory (Pekala 1982(Pekala , 1991c and wrote narratives following their respective stimulus conditions. Participants reported less imagery, joy, and absorption, but more internal dialogue, self-awareness, and muscular tension in the posture, compared to the sitting quietly, conditions. Goodman's results of specific posture (content-related) effects with naive participants were not replicated. Summary StatementThe major purposes of this study were to examine: (a) if monotonous percussion drumming for 15 minutes is associated with phenomenological effects different from a baseline condition of sitting quietly without such drumming; (b) if a certain standing body posture, when combined with monotonous percussion, is associated Anthropology of Consciousness 8(Z-3):69-87. Anthropology of Consciousness UK 2-3)]with phenomenological effects different from baseline and monotonous percussion drumming; and (c) if the inclusion of specific suggestions regarding the unique effects to be achieved by the posture and percussion drumming was associated with phenomenological effects different from posture and drumming without those suggestions.

Participants (N = 206) experienced 15-min of monotonous drumming either before or after hypnosis (Harvard scale). Participants completed the Phenomenology of Consciousness Inventory (PCI) in reference to the last 4-min of drumming. Stimulus order did not affect the objective trance levels as measured by the Harvard scores. The subjective trance level as measured by hypnoidal scores (predicted Harvard scores from the PCI) was significantly higher when drumming preceded hypnosis. Participants' estimated average trance level achieved during drumming fell in the medium range of susceptibility (5-8) (Pekala, 1995). Participants who achieved higher hypnoidal and Harvard scores were more likely to report relaxed feelings and shamanic-type experiences in narratives about their subjective experiences during drumming.

In the 1970s, Goodman rediscovered sacred, ancient, ecstatic trance postures (also called ritual body postures). A ritual body posture is an ecstatic trance 329