Abstract
The study examines the effects of emotional challenge under hypnosis on patients presenting symptoms of hyperventilation. Hypnosis proved a highly effective method of uncovering triggers for hyperventilation attacks, which were not easily apparent from either personal histories or the subjects' own awareness and recollection of events. Subjects who hyperventilated to hypnotic presentation of a situational stressor, but were negative to forced hyperventilation provocation testing, were found to differ significantly on aspects of the Leary Adjective Check List, when compared to those subjects who were positive to the forced hyperventilation provocation test. The authors conclude that there may be two quite different groups of hyperventilators, which would account for differences of opinion in the literature, and they briefly assess the implications of this proposal.