Pain

Conditioned pain modulation (CPM) paradigms provide a proxy measure of activity in the descending pain modulatory system. Cuff-pressure-algometry offers a standardised CPM assessment tool although comprehensive validation in large samples is lacking. To address this, we pooled cuff-algometry CPM data from 324 healthy participants across 8 studies. CPM magnitude was calculated as pain detection (PDT) and tolerance (PTT) threshold changes, assessed on the dominant leg in the presence and absence o...

ObjectivesMindfulness-based interventions (MBIs) have emerged as promising prophylactic episodic migraine treatments. The present study investigated biopsychosocial predictors and outcomes associated with formal, daily-life meditation practice in migraine patients undergoing MBI, and whether augmented mindfulness mechanistically underlies change. MethodsSecondary analyses of clinical trial comparing data 12-week mindfulness-based stress reduction (MBSR+; n = 50) to stress management for headach...

New-onset chronic pain is a common and debilitating symptom of Long COVID (LC) that remains not fully understood in terms of pathophysiology and therapeutic targets. A growing body of evidence in chronic pain syndromes similar to LC demonstrates an association between EEG alpha oscillatory activity and the experience of pain, with clinical studies showing maladaptive changes in oscillatory activity, particularly a slowing of alpha activity. This study aims to investigate the association between ...

The concept nociplastic pain has been developed for patients in whom clinical and psychophysical findings suggest a predominant central sensitization type of pain that is not fully explained as nociceptive or neuropathic. Here we tested, how well the recently published grading system differentiates between chronic primary pain or chronic secondary pain conditions. We recruited patients with Fibromyalgia (FMS, 41), Complex Regional Pain Syndrome (CRPS, 11), Osteoarthritis (OA, 21) or Peripheral ...

Complex Regional Pain Syndrome (CRPS) exhibits persistent disproportionate limb pain and hyperalgesia associated with neuroinflammatory and autonomic changes, typically after inciting limb injury. However, little is known about the progression of somatosensory changes over time. We reviewed cross-sectional studies employing standardised Quantitative Sensory Testing (QST) in accordance with the DFNS comprehensive somatosensory test protocol, stratified for CRPS duration. This study was registere...

Chronic pain conditions are complex syndromes characterized by a mosaic of biological, psychological, and social factors. We derived predictive models for the number of co- existing pain sites in the UK Biobank and identified a common risk score that classified different chronic pain conditions in cross-sectional data, predicted the development of chronic pain in pain-free individuals, and determined the spreading of chronic pain to multiple sites or its recovery nine years later. The features w...

Over 100 million Americans suffer from chronic pain (CP), which causes more disability than any other medical condition in the U.S. at a cost of $560-$635 billion per year (IOM, 2011). Opioid analgesics are frequently used to treat CP. However, long term use of opioids can cause brain changes such as opioid-induced hyperalgesia that, over time, increase pain sensation. Also, opioids fail to treat complex psychological factors that worsen pain-related disability, including beliefs about and emoti...

Childhood adversity is linked to persistent pain in adulthood. Nociceptive upregulation may play a role in this relationship. We investigated whether childhood adversity is associated with measures of nociceptive processing, and whether these associations differ by sex. In this experimental observational study, we enrolled pain-free adults with varying severity of childhood adversity, scored on the Childhood Trauma Questionnaire-Short Form. Measures of nociceptive processing included the surface...

IntroductionChronic pain in fibromyalgia may be driven by abnormal ongoing activity in a subclass of C-fibre nociceptors known as Type1B or CMi nociceptors. As is common in C-nociceptor microneurography studies, the modest patient numbers in these prior studies generate large confidence intervals around the point estimate of the prevalence of this abnormal activity. This complicates the interpretation of the relative importance of this ongoing nociceptor activity as a pain generating mechanism i...

ImportanceBiomarkers would greatly assist decision making in the diagnosis, prevention and treatment of chronic pain. ObjectiveThe present study aimed to undertake analytical validation of a sensorimotor cortical biomarker signature for pain consisting of two measures: sensorimotor peak alpha frequency (PAF) and corticomotor excitability (CME). DesignIn this cohort study (recruitment period: November 2020-October 2022), participants experienced a model of prolonged temporomandibular pain with ...

Chronic pain (CP) is a multidimensional condition characterized by physical, emotional, and cognitive symptoms. However, many neuroimaging studies investigating the brain mechanisms of CP have focused on single-domain measures, most commonly pain intensity. Incorporating multidimensional symptom profiles may advance the understanding of CP, its neural underpinnings, and the development of clinically actionable biomarkers. Here, we aimed to empirically derive symptom dimensions of CP and relate t...

Dysregulated brain reward systems have been observed in chronic pain. Using functional magnetic resonance imaging (fMRI) and a monetary incentive delay (MID) task, Martucci et al. (2018) showed that neural responses to reward anticipation and outcome are altered in patients with fibromyalgia. The current study aimed to replicate these results in a separate cohort of patients with fibromyalgia recruited at a new location using a similar study design. Twenty patients with fibromyalgia and 20 healt...

NFL players have a traumatic injury rate approaching 100%; chronic pain with decreased concentration occur commonly. This study examined the role of a novel focused muscle contraction therapy for the treatment of chronic pain and identified its impact on brain activity. Chronic pain was assessed by numerical score, neuropathic component, and impact on daily activities in 8 retired players. Brain activity was characterized by QEEG with low-resolution electromagnetic tomography analysis and functi...

BackgroundChronic pain is a global health priority. Mapping pain occurring at different body sites, and variability in brain circuitry related to widespread chronic pain, can elucidate nuanced roles of the central nervous system underlying chronic pain conditions. Chronic pain triples suicide risk; however, whether brain circuitry can inform this risk relationship has not been investigated. Methods11,298 participants (mean age: 64 years (range: 58-70), 55% female) with brain MRI from the UK Bio...

BackgroundChronic pain is a major healthcare problem associated with maladaptive brain circuit changes - many patients are unresponsive to all available therapies. Deep brain stimulation (DBS) is a promising treatment, but traditional targets have not proven consistently effective. DBS for pain may be improved by individualizing location and timing of stimulation based on real time brain measurements and patient reports. MethodsTo optimize personalized stimulation targets, we first performed a ...

Previous research has demonstrated the importance of the corticostriatal circuit in chronic pain. By focusing on nucleus accumbens (NAcc) circuits related to reward, we aimed to clarify how altered brain reward systems contribute to chronic pain. Using resting-state functional magnetic resonance imaging, we compared NAcc-medial prefrontal cortex (MPFC) functional connectivity in patients with fibromyalgia vs. healthy controls. Among patients, we analyzed the extent to which functional connectivi...

BackgroundNeuropathic pain (NP) is a debilitating chronic pain condition caused by injury or disease of the somatosensory nervous system. Accumulating evidence indicates that astrocytes play a central role in neuroinflammatory regulation and synaptic remodeling, thereby critically influencing the initiation and persistence of neuropathic pain. However, a comprehensive overview of research trends and knowledge structures in this field is still lacking. MethodsThe analysis was conducted based on ...

Chronic widespread pain (CWP) remains challenging due to its heterogenous causes and complex mechanisms. We analysed 2,923 plasma proteins from 29,254 UK Biobank participants. We first identified 811 proteins correlated with the presence of CWP cross- sectionally. We then created a sparse (top 10 proteins) and intricate (all significant proteins) proteomic-based score (ProtS) for CWP, both outperforming and improving the traditional clinical score (AUC: 0.82 and 0.88 vs 0.81 individually, and 0....

Repetitive transcranial magnetic stimulation (rTMS) to the primary motor cortex (M1) provides significant pain relief in [~]45% of chronic pain patients. Identifying biomarkers that predict treatment response before starting rTMS is essential for guiding clinical decision-making. Here, we used TMS combined with electroencephalography (TMS-EEG) to assess pre-treatment cortical function in 43 patients with chronic pain before receiving 12 sessions of therapeutic 10 Hz rTMS to M1 over eight weeks a...

Transcranial direct current stimulation (tDCS) might modulate neural activity and promote neural plasticity. This factorial randomized clinical trial compared a-tDCS on the left dorsolateral prefrontal cortex (l-DLPFC) or sham (s-tDCS), and a-tDCS or s-tDCS on the primary motor cortex (M1) in the connectivity analyses in eight regions of interest (ROIs) across eight resting-state electroencephalography (EEG) frequencies. We included 48 women with fibromyalgia, aged 30 to 65, randomly assigned to...