Hypnosis in Autonomic Function

Study Summary

This study will investigate the relationship between susceptibility to hypnosis and regulation of the autonomic nervous system (nerves that control involuntary body functions, such as heart rate and sweating). Hypnosis is a state of mind in which the individual is highly focused, relatively unaware of his or her surroundings, and possibly more able to accept and use therapeutic suggestions. People vary in their responsiveness, or susceptibility, while in hypnosis. People with certain conditions, such as chronic fatigue syndrome (CFS), chronic pain, posttraumatic stress disorder (PTSD), and generalized anxiety disorder (GAD) have altered hypnotic susceptibility. Patients with chronic orthostatic intolerance (COI) often have symptoms similar to those of individuals with CFS, chronic pain, PTSD, and GAD, and this study will examine how patients with COI respond to hypnosis as compared with healthy normal volunteers. COI is a group of disorders characterized by intolerance to prolonged standing. Among them are neurocardiogenic syncope (NCS), in which patients have recurrent episodes of sudden loss of consciousness, and postural tachycardia syndrome (POTS), in which patients have a sustained increase in heart rate after standing. In addition to the comparison of COI and normal volunteer responses to hypnosis, the study will examine how hypnotic susceptibility is related to the ability to control autonomic functions such as blood pressure, heart rate, and sweating. The autonomic nervous system is activated when the body is stressed, not only from physical stimuli such as cold temperature, but also from mental stimuli, such as seeing a rattlesnake up close. Hypnosis may, therefore, be a useful tool to understand how the mind controls the autonomic nervous system. Healthy normal volunteers and patients with NCS or POTS who are 18 years of age or older may be eligible for this two-part study. In part 1, participants complete a questionnaire and are then tested for hypnoti