Pain
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The current study applied a model of pain communication to examine the distinction between verbal and nonverbal pain expression in their prediction of punishing, empathic, and solicitous spouse responses to patient pain. It was hypothesized that on days when patients engaged in more nonverbal expression, spouses would respond more positively (ie, with less punishing and more solicitous and empathic behavior). The same pattern was predicted for verbal expression. ⋯ The predicted positive main effect of nonverbal expression on empathic and solicitous responses was supported by the data, as was the positive main effect for verbal pain expression. Results from moderation analyses partially supported our hypothesis in that patients' nonverbal pain expression was even more strongly related to empathic and solicitous spouse responses on days of high verbal pain expression, and patients were buffered from spouse punishing responses on days when both nonverbal and verbal expression were high. These findings suggest that pain expression in both verbal and nonverbal modes of communication is important for positive and negative spousal responses.
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Randomized Controlled Trial
Perceptual bias in pain: A switch looks closer when it will relieve pain than when it won't.
Pain is fundamental to survival, as are our perceptions of the environment. It is often assumed that we see our world as a read-out of the sensory information that we receive; yet despite the same physical makeup of our surroundings, individuals perceive differently. What if we "see" our world differently when we experience pain? Until now, the causal effect of experimental pain on the perception of an external stimulus has not been investigated. ⋯ The critical result was a strong interaction between reaching and pain [F(1,181)=4.8, P=0.03], such that when participants experienced pain and were required to reach for a switch that would turn off the experimental stimulus, they judged the distance to that switch to be closer, as compared to the other 3 conditions (mean of the true distance 92.6%, 95% confidence interval 89.7%-95.6%). The judged distance was smaller than estimates in the other 3 conditions (mean±SD difference >5.7%±2.1%, t(181) >3.5, P<0.01 for all 3 comparisons). We conclude that the perception of distance to an object is modulated by the behavioural relevance of the object to ongoing pain.
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Chronic pain often accompanies immune responses and immune cells are known to be involved in chronic pain. Store-operated calcium (SOC) channels are calcium-selective cation channels and play an important role in the immune system. YM-58483, a potent SOC channel inhibitor, has been shown to inhibit cytokine production from immune cells and attenuate antigen-induced hypersensitivity reactions. ⋯ YM-58483 diminished CFA-induced paw edema, and reduced production of TNF-α, IL-1β and PGE2 in the CFA-injected paw. In vitro, SOC entry in nociceptors was more robust than in nonnociceptors, and the inhibition of SOC entry by YM-58483 in nociceptors was much greater than in nonnociceptors. Our findings indicate that YM-58483 is a potent analgesic and suggest that SOC channel inhibitors may represent a novel class of therapeutics for pain.
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We previously discovered that when faced with a challenging cognitive task in the context of pain, some people prioritize task performance, while in others, pain results in poorer performance. These behaviours, designated respectively as A- and P-types (for attention dominates vs pain dominates), may reflect pain coping strategies, resilience or vulnerabilities to develop chronic pain, or predict the efficacy of treatments such as cognitive behavioural therapy. Here, we used a cognitive interference task and pain stimulation in 80 subjects to interrogate psychophysical, psychological, brain structure and function that distinguish these behavioural strategies. ⋯ Brain imaging revealed structural and functional brain features that characterized these behavioural strategies. Compared to the performance-oriented A group, the P group had (1) more gray matter in regions implicated in pain and salience (anterior insula, anterior midcingulate cortex, supplementary motor area, orbitofrontal cortex, thalamus, caudate), (2) greater functional connectivity in sensorimotor and salience resting-state networks, (3) less white matter integrity in the internal and external capsule, anterior thalamic radiation and corticospinal tract, but (4) were indistinguishable based on sex, pain sensitivity, neuroticism, and pain catastrophizing. These data may represent neural underpinnings of how task performance vs pain is prioritized and provide a framework for developing personalized pain therapy approaches that are based on behaviour-structure-function organization.
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The perception of pain changes as people age. However, how aging affects the quality of pain and whether specific pain-processing brain regions mediate this effect is unclear. We hypothesized that specific structures in the cerebral nociceptive system mediate the effect of aging on the variation in different pain psychophysical measures. ⋯ The analyses of gray matter volume revealed that key nociceptive cerebral regions did not undergo significant age-related gray matter loss. However, the volume of the cingulate cortex covaried with pain perception after adjusting for corresponding neural activity to pain. These results suggest that age-related functional alterations in pain-processing regions are responsible for changes in pain perception during normal aging.