Reality monitoring in hypnosis: a pilot investigation.

In a pilot investigation of reality monitoring in hypnosis, 10 high and 10 low hypnotizable participants were administered a hypnotic suggestion to hallucinate a visual shape on a wall. For half the participants, an image was subtly projected onto the wall at the commencement of the suggestion and then subsequently removed. For the remaining participants, the projected image was initially absent and subsequently projected. Participants completed ratings of belief in the suggestion during hypnosis and also provided subjective reports of the suggestion during a subsequent Experiential Analysis Technique session. High hypnotizable participants who had the projected image introduced at the end of the suggestion provided comparable belief ratings when the image was present and absent. In contrast, highs who had the projected image presented first reported less belief when the image was absent than when it was present. Low hypnotizable participants rated the hallucination more strongly when the image was projected than when it was not projected. These pilot data are discussed in terms of developing a paradigm to objectively index the perceived reality of hypnotically suggested experiences.