title: Mindfulness Meditation-Based Pain Relief Employs Different Neural Mechanisms Than Placebo and Sham Mindfulness Meditation-Induced Analgesia.
abstract: Mindfulness meditation reduces pain in experimental and clinical settings. However, it remains unknown whether mindfulness meditation engages pain-relieving mechanisms other than those associated with the placebo effect (e.g., conditioning, psychosocial context, beliefs). To determine whether the analgesic mechanisms of mindfulness meditation are different from placebo, we randomly assigned 75 healthy, human volunteers to 4 d of the following: (1) mindfulness meditation, (2) placebo conditioning, (3) sham mindfulness meditation, or (4) book-listening control intervention. We assessed intervention efficacy using psychophysical evaluation of experimental pain and functional neuroimaging. Importantly, all cognitive manipulations (i.e., mindfulness meditation, placebo conditioning, sham mindfulness meditation) significantly attenuated pain intensity and unpleasantness ratings when compared to rest and the control condition (p < 0.05). Mindfulness meditation reduced pain intensity (p = 0.032) and pain unpleasantness (p < 0.001) ratings more than placebo analgesia. Mindfulness meditation also reduced pain intensity (p = 0.030) and pain unpleasantness (p = 0.043) ratings more than sham mindfulness meditation. Mindfulness-meditation-related pain relief was associated with greater activation in brain regions associated with the cognitive modulation of pain, including the orbitofrontal, subgenual anterior cingulate, and anterior insular cortex. In contrast, placebo analgesia was associated with activation of the dorsolateral prefrontal cortex and deactivation of sensory processing regions (secondary somatosensory cortex). Sham mindfulness meditation-induced analgesia was not correlated with significant neural activity, but rather by greater reductions in respiration rate. This study is the first to demonstrate that mindfulness-related pain relief is mechanistically distinct from placebo analgesia. The elucidation of this distinction confirms the existence of multiple, cognitively driven, supraspinal mechanisms for pain modulation.
  
  
  CONCLUSIONS
  Recent findings have demonstrated that mindfulness meditation significantly reduces pain. Given that the "gold standard" for evaluating the efficacy of behavioral interventions is based on appropriate placebo comparisons, it is imperative that we establish whether there is an effect supporting meditation-related pain relief above and beyond the effects of placebo. Here, we provide novel evidence demonstrating that mindfulness meditation produces greater pain relief and employs distinct neural mechanisms than placebo cream and sham mindfulness meditation. Specifically, mindfulness meditation-induced pain relief activated higher-order brain regions, including the orbitofrontal and cingulate cortices. In contrast, placebo analgesia was associated with decreased pain-related brain activation. These findings demonstrate that mindfulness meditation reduces pain through unique mechanisms and may foster greater acceptance of meditation as an adjunct pain therapy.
authors.affiliation: Department of Neurobiology and Anatomy and fzeidan@wakehealth.edu.
authors.forename: Fadel
authors.initials: F
authors.lastname: Zeidan
authors.affiliation: Department of Neurobiology and Anatomy and.
authors.forename: Nichole M
authors.initials: NM
authors.lastname: Emerson
authors.affiliation: Department of Neurobiology and Anatomy and.
authors.forename: Suzan R
authors.initials: SR
authors.lastname: Farris
authors.affiliation: Department of Psychology, University of North Carolina at Charlotte, Charlotte, North Carolina 28262, and.
authors.forename: Jenna N
authors.initials: JN
authors.lastname: Ray
authors.affiliation: Department of Radiology, Wake Forest School of Medicine, Winston-Salem, North Carolina 27157.
authors.forename: Youngkyoo
authors.initials: Y
authors.lastname: Jung
authors.affiliation: Department of Neurobiology and Anatomy and.
authors.forename: John G
authors.initials: JG
authors.lastname: McHaffie
authors.affiliation: Department of Anesthesiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio 45229.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Coghill
mesh_terms: D000328:Adult; D001921:Brain / Q000098:blood supply / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D064866:Mindfulness / Q000379:methods*; D010100:Oxygen / Q000097:blood; D010146:Pain / Q000523:psychology / Q000534:rehabilitation*; D010147:Pain Measurement; D017288:Pain Threshold / Q000502:physiology*; D010812:Physical Stimulation / Q000009:adverse effects; D015990:Placebo Effect; D011601:Psychophysics; D012044:Regression Analysis; D012119:Respiration; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: arterial spin labeling; fMRI; mindfulness meditation; pain; placebo; psychophysics