title: Sensitivity and specificity of hypnosis effects on gastric myoelectrical activity.
abstract: OBJECTIVE
  The effects of hypnosis on physiological (gastrointestinal) functions are incompletely understood, and it is unknown whether they are hypnosis-specific and gut-specific, or simply unspecific effects of relaxation.
  
  
  METHODS
  Sixty-two healthy female volunteers were randomly assigned to either a single session of hypnotic suggestion of ingesting an appetizing meal and an unappetizing meal, or to relax and concentrate on having an appetizing or unappetizing meal, while the electrogastrogram (EGG) was recorded. At the end of the session, participants drank water until they felt full, in order to detect EGG-signal changes after ingestion of a true gastric load. During both conditions participants reported their subjective well-being, hunger and disgust at several time points.
  
  
  RESULTS
  Imagining eating food induced subjective feelings of hunger and disgust as well as changes in the EGG similar to, but more pronounced than those seen with a real gastric water load during both hypnosis and relaxation conditions. These effects were more pronounced when imagining an appetizing meal than with an unappetizing meal. There was no significant difference between the hypnosis and relaxation conditions.
  
  
  CONCLUSIONS
  Imagination with and without hypnosis exhibits similar changes in subjective and objective measures in response to imagining an appetizing and an unappetizing food, indicating high sensitivity but low specificity.
authors.affiliation: Department of Psychosomatic Medicine, University Hospital, Tübingen, Germany.
authors.forename: Paul
authors.initials: P
authors.lastname: Enck
authors.affiliation: Department of Internal Medicine II, University Hospital, Würzburg, Germany.
authors.forename: Jochen
authors.initials: J
authors.lastname: Hefner
authors.affiliation: Department of Health Psychology, Institute of Psychology and Education, University of Ulm, Ulm, Germany.
authors.forename: Beate M
authors.initials: BM
authors.lastname: Herbert
authors.affiliation: Central Research Department, Ivano-Frankivsk National Medical University, Ivano-Frankivsk, Ukraine.
authors.forename: Nazar
authors.initials: N
authors.lastname: Mazurak
authors.affiliation: Department of Psychosomatic Medicine, University Hospital, Tübingen, Germany.
authors.forename: Katja
authors.initials: K
authors.lastname: Weimer
authors.affiliation: Department of Psychology, Clemson University, Clemson, South Carolina, United States of America.
authors.forename: Eric R
authors.initials: ER
authors.lastname: Muth
authors.affiliation: Department of Psychosomatic Medicine, University Hospital, Tübingen, Germany.
authors.forename: Stephan
authors.initials: S
authors.lastname: Zipfel
authors.affiliation: Department of Psychosomatic Medicine, University Hospital, Tübingen, Germany.
authors.forename: Ute
authors.initials: U
authors.lastname: Martens
mesh_terms: D000328:Adult; D001066:Appetite / Q000502:physiology; D004435:Eating / Q000502:physiology / Q000523:psychology; D004576:Electromyography; D005260:Female; D005502:Food; D005769:Gastrointestinal Motility / Q000502:physiology; D006801:Humans; D006990:Hypnosis / Q000379:methods; D007092:Imagination / Q000502:physiology; D019518:Postprandial Period; D012063:Relaxation / Q000502:physiology / Q000523:psychology; D012680:Sensitivity and Specificity; D013270:Stomach / Q000502:physiology*; D055815:Young Adult