The Effect of Hypnosis on Blood Concentrations of Endocannabinoids
Condition: Hypnosis; Endocannabinoids; Analgesia
MeSH terms: Agnosia
Study type: Interventional

Summary: 
      Introduction: Many interventions such as hypnosis, mindfulness meditation, conditioned pain
      modulation and placebos have been shown to effectively reduce pain both in the laboratory and
      in clinical settings. However, little is known about their neurophysiological mechanisms of
      action. Analgesia induced by these techniques is thought to be based on opioidergic and
      non-opioidergic mechanisms (potentially endocannabinoid mechanisms). Objective: Our main
      objective is to evaluate the effect of hypnosis, meditation, conditioned pain modulation and
      placebo on blood concentrations of endocannabinoids (anandamide, 2-arachidonylglycerol,
      N-palmitoyl-ethanolamine, N-oleoylethanolamide), endogenous opioids (β-endorphins, met /
      leu-enkephalins, and dynorphins) and norepinephrine in healthy adults. Methods: This study is
      based on a single-group pre-experimental research design in which two experimental sessions
      including hypnosis or meditation, conditioned pain modulation and placebo interventions will
      be completed by all participants. In order to have a better description of the
      sociodemographic and clinical characteristics of the sample, information will be collected by
      questionnaires or tests filled by participants at baseline, including: age, sex, language,
      culture, religion, salary, menstrual cycle of women, medication (if any), mood, anxiety, pain
      catastrophizing, mindfulness, hypnotic susceptibility, and DNA information. Outcome measures
      will be collected before, during and after each intervention. The primary outcome is plasma
      concentrations of endocannabinoids. Secondary measurements include plasma concentrations of
      endogenous opioids and norepinephrine; change in pain intensity during the thermal noxious
      stimuli; and autonomic nervous system variability (as measured by heart rate variability).
      Anticipated results: The investigators expect a positive relationship between the change in
      pain intensity (analgesia) induced by the interventions (hypnosis, meditation, conditioned
      pain modulation, and placebo) and the change (increase) in plasma concentrations of
      endocannabinoids, opioids, and norepinephrine in healthy adults. It is also believed that the
      interventions will influence heart rate variability. Moreover, it is expected that there will
      be a relationship between the efficiency of the analgesic intervention and some gene
      polymorphisms associated to pain modulation and endocannabinoids, opioids or norepinephrine
      in healthy individuals.
    


Intervention name(s): Hypnosis; Meditation; Conditioned pain modulation; Placebo Oral Tablet
Intervention type(s): Behavioral; Behavioral; Other; Drug
Intervention description(s): Hypnosis is a therapeutic method in which the experimenter or therapist make suggestions to individuals after they have undergone a hypnotic induction. This induction is a relaxation procedure designed to focus one's mind and to induce a hypnotic trance in individuals. The hypnotic trance consists in a state of deep absorption, concentration and altered sensations, cognitions and behaviors. Hypnosis can be used for pain control in experimental and clinical settings. In this study, standardized hypnosis including a relaxation technique for the hypnotic induction and a direct hypnotic analgesia technique for the hypnotic suggestions will be used.; Meditation is a relaxation method that can be used to reduce pain symptoms and pain perception in clinical and experimental situations. In this study, a standardized mindfulness meditation session of 20 minutes will be used to induce a relaxation and an analgesic effect in participants. Mindfulness meditation is a practice intended to increase mindfulness and awareness of the self and the environment by techniques of controlled breathing, focus on neutral elements, and observation of one's thoughts and emotions without judgment.; Conditioned pain modulation (CPM) is a pain inhibition mechanism that is used to assess endogenous analgesia capacity. The method to evaluate CPM in healthy individuals and patients with pain includes both a conditioning stimulus (a noxious stimulus that induces CPM) and a test stimulus (a noxious stimulus used to evaluate the analgesic response to the conditioning stimulus). In this study, the conditioning stimulus will be a cold pressor test (two-minutes immersion of one hand in ice water) and the test stimulus will be a two-minutes thermal noxious stimulus delivered by a contact thermode.; A placebo is a substance (or treatment) with no active therapeutic effect. The placebo effect (analgesia) in this study will be induced by the oral administration of one inert tablet (sugar pill). The tablet is a round, hard, white, flat-faced tablet with no active ingredient. The participant is told that the tablet is an active drug, more specifically an analgesic or a painkiller, that is used to achieve analgesia, relief from pain. This placebo condition is used to induce a diffuse analgesic effect in participants.
Other intervention name(s): Hypnotic suggestions; Mindfulness meditation; CPM; Pain modulation; Diffuse noxious inhibitory control; DNIC; Hetero-segmental counter-irritation; Placebo analgesia; Placebo effect; Placebo
Intervention MeSH terms: Hypnotics and Sedatives
Intervention model: Single Group Assignment
Intervention model description: Repeated measures on a single group of participants
Masking: None (Open Label)
Primary purpose: Basic Science
Keywords: Hypnosis; Meditation; Conditioned pain modulation; Placebo; Endocannabinoids; Opioid peptides; Norepinephrine; Pain; Analgesia; Genes; Heart rate variability