A Painful Peek into the Underlying Mechanisms of Mindfulness

The burgeoning scientific interest in the clinical benefits of mindfulness has resulted in an extensive body of research linking mindfulness-based practices to improvements across a wide range of pain-related outcomes. Yet, a clear understanding of the mechanisms via which mindfulness conveys its purported effects is still lacking. Novel insights from neuroimaging studies suggest that mindfulness may alleviate pain via unique neural mechanisms characterised by increased pain-related sensory processing and abatement of evaluative and memory-related processes. In light of these observations, recently formulated predictive processing accounts posit that the non-elaborative sustained attention to present-centred experience during mindfulness practice may lead to a weighing of incoming sensory information over prior information during the perceptual process. This interpretation hence raises the intriguing possibility that mindfulness may mitigate the well-documented biasing influence of prior expectations and information on pain perception. We tested this hypothesis across three separate pain expectancy-manipulation paradigms.
Study 1 investigated whether the instructed use of a mindfulness strategy vs. an vsernative cognitive regulatory strategy (i.e., suppression) differentially modulates susceptibility to conditioned hypoalgesic and hyperalgesic effects during an implicit classical pain conditioning paradigm. The results revealed that while participants assigned to the suppression condition exhibited preserved cue-induced hypoalgesic effects, no such effects were observed for the mindfulness condition.
In Study 2, we employed a recently developed pain categorization paradigm to test whether trait mindfulness level modulates the influence of prior categorical information on pain perception and pain-related decision-making. Although the paradigm successfully elicited categorization-induced perceptual biases, modulation of these effects did not differ across individuals with high and low trait mindfulness.
Finally, in Study 3, we used an explicit pain-cueing paradigm in which we aimed to address some of the methodological limitations of Study 1. The analyses revealed that high trait mindfulness scorers reported smaller cue-induced hyperalgesic effects for pain unpleasantness ratings compared to low trait mindfulness scorers. There were, however, no group differences in cue-induced hypoalgesia.
Results from the pain conditioning studies provide partial support for the notion that mindfulness may mitigate the influence of prior expectations and information on pain perception. These findings add to growing evidence suggesting that mindfulness may alleviate pain via neuropsychological mechanisms opposite to those typically involved in conditioning/placebo-induced hypoalgesia. The discussion section explores potential methodological and mechanistic explanations for the asymmetric pattern of results observed across the three studies and considers the potential clinical implications of those findings.