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 Ͻ 0.05). Mindfulness meditation reduced pain intensity (p ϭ 0.032) and pain unpleasantness (p Ͻ 0.001) ratings more than placebo analgesia. Mindfulness meditation also reduced pain intensity (p ϭ 0.030) and pain unpleasantness (p ϭ 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.

Mindfulness Interventions

“…Other active group-based interventions have been effectively implemented, ranging from relaxation interventions (Creswell et al 2016) to targeted health education programs (Morone et al 2016). The brief mindfulness intervention literature (consisting of interventions that last two weeks or less) also offers a number of well-matched active control interventions, ranging from attention control training programs (e.g., listening to the same guided mindfulness exercise with the instruction to count the number of verbs) (Koole et al 2009, Schofield et al 2015, to placebo conditioning (Zeidan et al 2015), and health education interventions (Mrazek et al 2013). One intriguing new approach in the brief mindfulness interventions literature offers sham mindfulness meditation training where participants are instructed periodically "to take a deep breath as we sit here in mindfulness meditation" without any explicit instructions on how to foster mindful awareness (Zeidan et al 2015).…”

“…The brief mindfulness intervention literature (consisting of interventions that last two weeks or less) also offers a number of well-matched active control interventions, ranging from attention control training programs (e.g., listening to the same guided mindfulness exercise with the instruction to count the number of verbs) (Koole et al 2009, Schofield et al 2015, to placebo conditioning (Zeidan et al 2015), and health education interventions (Mrazek et al 2013). One intriguing new approach in the brief mindfulness interventions literature offers sham mindfulness meditation training where participants are instructed periodically "to take a deep breath as we sit here in mindfulness meditation" without any explicit instructions on how to foster mindful awareness (Zeidan et al 2015). This sham mindfulness procedure has been effective in controlling for positive treatment expectancies in studies, yet does not show the same pain relief benefits as actual mindfulness meditation training (Zeidan et al 2010b(Zeidan et al , 2015.…”

“…One intriguing new approach in the brief mindfulness interventions literature offers sham mindfulness meditation training where participants are instructed periodically "to take a deep breath as we sit here in mindfulness meditation" without any explicit instructions on how to foster mindful awareness (Zeidan et al 2015). This sham mindfulness procedure has been effective in controlling for positive treatment expectancies in studies, yet does not show the same pain relief benefits as actual mindfulness meditation training (Zeidan et al 2010b(Zeidan et al , 2015.…”

“…Formal mindfulness meditation practices (e.g., mindful awareness of breathing) have been shown to activate a distributed network of brain regions, including the insula, putamen, somatosensory cortex, and portions of the anterior cingulate cortex and prefrontal cortex (Hölzel et al 2007, Tomasino & Fabbro 2016, Zeidan et al 2015. There is also some initial evidence that mindfulness interventions might structurally alter the brain, increasing gray matter density in the hippocampus (Hölzel et al 2011a), although well-controlled mindfulness intervention studies are lacking.…”

Predictors of Meditation Success: A Literature Review

“…Studies have shown mindfulness to activate the areas associated with pain management, such as the orbit frontal and cingulated cortices reduce cortisol levels and improve neuroendocrine responses to psychosocial stress [12][13][14]. Lazar et al, tested the hypothesis that regular meditation practice is associated with differences in the structures in the brain and with magnetic resonance imaging determined the thickness of the cerebral cortex of experienced meditators to be significantly different than non-meditators (significance, p<0.001) [15].…”