title: Pain modulation as a function of hypnotizability: Diffuse noxious inhibitory control induced by cold pressor test vs explicit suggestions of analgesia.
abstract: The aim of the present study was to compare the effects of explicit suggestions of analgesia and of the activation of the Diffuse Noxious Inhibitory Control (DNIC) by cold pressor test on pain perception and heart rate in healthy participants with high (highs, N=18), low (lows, N=18) and intermediate scores of hypnotizability (mediums, N=15) out of hypnosis. Pain reports and the stimulus-locked heart rate changes induced by electrical nociceptive stimulation of the left hand were studied in the absence of concomitant stimuli (Control), during suggestions of analgesia (SUGG, glove analgesia) and during cold pressor test used as a conditioning stimulus to the right hand (DNIC, water temperature=10-12°C) in the REAL session. Participants were submitted also to a SHAM session in which the DNIC water temperature was 30°C and the suggestions for analgesia were substituted with weather forecast information. Both suggestions and DNIC reduced pain significantly in all subjects; however, the percentage of reduction was significantly larger in highs (pain intensity=55% of the control condition) than in mediums (70%) and lows (80%) independently of the REAL/SHAM session and of the specific pain manipulation. Heart rate was not modulated consistently with pain experience. Findings indicate that both suggestions and DNIC influence pain experience as a function of hypnotizability and suggest that both sensory and cognitive mechanisms co-operate in DNIC induced analgesia.
authors.affiliation: Dept. Surgical, Medical, Molecular and Critical Area, University of Pisa, Pisa, Italy.
authors.forename: Fabrizia
authors.initials: F
authors.lastname: Fidanza
authors.affiliation: Institute of Clinical Physiology, National Council of Research, Pisa, Italy.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Varanini
authors.affiliation: Aplysia Onlus, GIFT Institute of Integrative Medicine, Pisa, Italy.
authors.forename: Antonella
authors.initials: A
authors.lastname: Ciaramella
authors.affiliation: Dept. Medicine, Surgery and Neuroscience, Siena University, Siena, Italy.
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Carli
authors.affiliation: Dept. Translational Research and New Technologies in Medicine and Surgery, Pisa University, Pisa, Italy. Electronic address: enricals@dfb.unipi.it.
authors.forename: Enrica L
authors.initials: EL
authors.lastname: Santarcangelo
mesh_terms: D000328:Adult; D000698:Analgesia / Q000523:psychology*; D003080:Cold Temperature; D059328:Diffuse Noxious Inhibitory Control / Q000502:physiology*; D005260:Female; D064368:Healthy Volunteers; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D006990:Hypnosis / Q000379:methods*; D008297:Male; D010146:Pain / Q000503:physiopathology / Q000523:psychology*; D059408:Pain Management; D010147:Pain Measurement; D010812:Physical Stimulation / Q000009:adverse effects; D011601:Psychophysics; D018709:Statistics, Nonparametric; D055815:Young Adult
keywords: Analgesia; Cold pressor test; Hypnotic susceptibility; Hypnotizability; Pain; Suggestions