The thermal grill elicits central sensitization.

The thermal grill, in which innocuous warm and cool stimuli are interlaced, can produce a paradoxical burning pain sensation-the thermal grill illusion (TGI). Although the mechanisms underlying TGI remain unclear, prominent theories point to spinal dorsal horn integration of innocuous thermal inputs to elicit pain. It remains unknown whether the TGI activates peripheral nociceptors, or solely thermosensitive afferents that are integrated within the spinal cord to give rise to a painful experience.

Peak Alpha Frequency Is Not Significantly Altered by Five Days of Experimental Pain and Repetitive Transcranial Stimulation of the Left Dorsolateral Prefrontal Cortex.

Repetitive transcranial magnetic stimulation (rTMS) holds promise as a noninvasive pain treatment. Given the link between individual peak alpha frequency (PAF) of resting-state electroencephalographic recordings and pain sensitivity, and the potential for rTMS to modulate PAF, we investigated these relationships through a secondary analysis of established rTMS-induced analgesia in an experimental model of sustained muscle pain. In a randomized, single-blind, sham-controlled experiment, 30 healthy adults underwent either active (n = 15) or sham (n = 15) high-frequency rTMS (20 min) to the left dorsolateral prefrontal cortex for five consecutive days following the induction of sustained experimental pain by nerve growth factor (NGF) injected into the right extensor carpi radialis brevis muscle.

Resting-state functional connectivity of the marmoset claustrum.

The common marmoset () has been recently developed as a nonhuman primate model useful for studying behaviour, neurology, and higher-level cognitive processes considering their phylogenetic proximity to humans. Here, we investigated the resting-state functional connectivity (RSFC) of the marmoset claustrum, a small, highly connected subcortical structure. Using an open resource of 234 functional MRI scans from awake marmosets, we found claustrum connectivity to the prefrontal cortex, posterior parietal cortex, temporal cortices, cingulate cortex, sensory cortices, limbic areas, basal ganglia, and cerebellum.

The effect of prolonged elbow pain and rTMS on TMS-evoked potentials: A TMS-EEG study.

Recent studies using combined transcranial magnetic stimulation (TMS) and electroencephalography (EEG) have shown that pain leads to an increase in the N45 peak of the TMS-evoked potential (TEP), potentially linked to changes in GABAergic activity. Conversely, 10 Hz repetitive TMS (10 Hz-rTMS), which provides pain relief, reduces the N45 peak. However, these studies used brief pain stimuli (lasting minutes), limiting their clinical relevance.

Salience or value: what drives priority in pain-cognition interactions?

The evolutionary function of pain is to protect against injury by capturing attention and motivating nocifensive behavior. This makes pain inherently salient and capable of disrupting the pursuit of competing goals. However, this interference can sometimes be overridden by concurrent demands.

The human claustrum initiates networks for externally and internally driven task demands.

Unlabelled: Cognitive control is believed to arise from interactions among multiple brain networks depending on task demands. Although several debilitating neuropsychiatric disorders are characterized by cognitive network dysfunction, the neural circuit mechanisms supporting task-dependent network activation are largely unknown. Because the claustrum possesses widespread connections with cortex and can synchronize distant cortical regions, we tested whether the claustrum activates task-dependent network states using fMRI during working memory ( = 420) and autobiographical memory ( = 35), tasks which elicit opposing responses from key cognitive control networks.

Consensus Recommendations to Establish Reporting Standards in fMRI of Migraine: A Delphi Study.

Background And Objectives: Migraine is a multifaceted primary headache disorder. In neuroimaging of migraine, fMRI has been used to elucidate pathophysiology or monitor treatment effects. The current literature, however, is highly heterogeneous regarding reported variables and methodologies.

Predicting Individual Pain Sensitivity Using a Novel Cortical Biomarker Signature.

Importance: Biomarkers would greatly assist decision-making in the diagnosis, prevention, and treatment of chronic pain.

Objective: To undertake analytical validation of a sensorimotor cortical biomarker signature for pain consisting of 2 measures: sensorimotor peak alpha frequency (PAF) and corticomotor excitability (CME).

Design, Setting, And Participants: This cohort study at a single center (Neuroscience Research Australia) recruited participants from November 2020 to October 2022 through notices placed online and at universities across Australia.

Posterior-superior insula repetitive transcranial magnetic stimulation reduces experimental tonic pain and pain-related cortical inhibition in humans.

High frequency repetitive transcranial magnetic stimulation (rTMS) to the posterior-superior insula (PSI) may produce analgesic effects. However, the alterations in cortical activity during PSI-rTMS analgesia remain poorly understood. The present study aimed to determine whether tonic capsaicin-induced pain and cortical inhibition (indexed using TMS-electroencephalography) are modulated by PSI-rTMS.

The effect of prolonged elbow pain and rTMS on cortical inhibition: A TMS-EEG study.

Introduction: Recent studies using combined transcranial magnetic stimulation (TMS) and electroencephalography (EEG) have shown that pain leads to an increase in the N45 peak of the TMS-evoked potential (TEP), which is mediated by GABAergic inhibition. Conversely, 10Hz repetitive TMS (10Hz-rTMS), which provides pain relief, reduces the N45 peak. However, these studies used brief pain stimuli (lasting minutes), limiting their clinical relevance.

A 5-day course of repetitive transcranial magnetic stimulation before pain onset ameliorates future pain and increases sensorimotor peak alpha frequency.

Repetitive transcranial magnetic stimulation (rTMS) has shown promise as an intervention for pain. An unexplored research question is whether the delivery of rTMS prior to pain onset might protect against a future episode of prolonged pain. The present study aimed to determine whether (1) 5 consecutive days of rTMS delivered prior to experimentally induced prolonged jaw pain has a prophylactic effect on future pain intensity and (2) whether these effects were accompanied by increases in corticomotor excitability (CME) and/or sensorimotor peak alpha frequency (PAF).

A 5-day course of rTMS before pain onset ameliorates future pain and increases sensorimotor peak alpha frequency.

Repetitive transcranial magnetic stimulation (rTMS) has shown promise as an intervention for pain. An unexplored research question is whether the delivery of rTMS might protect against a future episode of prolonged pain. The present study aimed to determine i) whether 5 consecutive days of rTMS delivered prior to experimentally-induced prolonged jaw pain could reduce future pain intensity and ii) whether any effects of rTMS on pain were mediated by changes in corticomotor excitability (CME) and/or sensorimotor peak alpha frequency (PAF).

Can non-invasive brain stimulation modulate peak alpha frequency in the human brain? A systematic review and meta-analysis.

Peak alpha frequency (PAF), the dominant oscillatory frequency within the alpha range (8-12 Hz), is associated with cognitive function and several neurological conditions, including chronic pain. Manipulating PAF could offer valuable insight into the relationship between PAF and various functions and conditions, potentially providing new treatment avenues. This systematic review aimed to comprehensively synthesise effects of non-invasive brain stimulation (NIBS) on PAF speed.

Pathological claustrum activity drives aberrant cognitive network processing in human chronic pain.

Aberrant cognitive network activity and cognitive deficits are established features of chronic pain. However, the nature of cognitive network alterations associated with chronic pain and their underlying mechanisms require elucidation. Here, we report that the claustrum, a subcortical nucleus implicated in cognitive network modulation, is activated by acute painful stimulation and pain-predictive cues in healthy participants.

Meditation Practice, Mindfulness, and Pain-Related Outcomes in Mindfulness-Based Treatment for Episodic Migraine.

Objectives: Mindfulness-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.

Methods: Secondary analyses of clinical trial data comparing a 12-week enhanced mindfulness-based stress reduction course (MBSR + ; = 50) to stress management for headache (SMH; = 48) were conducted.

Secondary analysis: heat and self-report pain sensitivity associate with biological sex and racialized sociocultural group but may not be mediated by anxiety or pain catastrophizing.

Introduction: Previous studies have demonstrated associations between sex and racialized group on pain sensitivity and tolerance. We analyzed the association of sex and racialized group on heat pain sensitivity, sensibility to painful suprathreshold mechanical pain (STMP), and pain sensitivity questionnaire (PSQ). We hypothesized that anxiety and pain catastrophizing reported by racialized minority groups and women would mediate enhanced pain sensitivity.

Intensive Mindfulness Meditation Reduces Frequency and Burden of Migraine: An Unblinded Single-Arm Trial.

Objectives: Preventing migraine headaches and improving the quality of life for patients with migraine remains a challenge. We hypothesized intensive meditation training would reduce the disease burden of migraine.

Method: An unblinded trial was analyzed as a single cohort exposed to a silent 10-day Vipassana meditation retreat that included 100 hr of sitting meditation.

Effects of Savoring Meditation on Positive Emotions and Pain-Related Brain Function: A Mechanistic Randomized Controlled Trial in People With Rheumatoid Arthritis.

Positive emotions are a promising target for intervention in chronic pain, but mixed findings across trials to date suggest that existing interventions may not be optimized to efficiently engage the target. The aim of the current pilot mechanistic randomized controlled trial was to test the effects of a positive emotion-enhancing intervention called Savoring Meditation on pain-related neural and behavioral targets in patients with rheumatoid arthritis. Participants included 44 patients with a physician-confirmed diagnosis of rheumatoid arthritis (n = 29 included in functional magnetic resonance imaging (fMRI) analyses), who were randomized to either Savoring Meditation or a Slow Breathing control.

Combined transcranial magnetic stimulation and electroencephalography reveals alterations in cortical excitability during pain.

Transcranial magnetic stimulation (TMS) has been used to examine inhibitory and facilitatory circuits during experimental pain and in chronic pain populations. However, current applications of TMS to pain have been restricted to measurements of motor evoked potentials (MEPs) from peripheral muscles. Here, TMS was combined with electroencephalography (EEG) to determine whether experimental pain could induce alterations in cortical inhibitory/facilitatory activity observed in TMS-evoked potentials (TEPs).

Pathological claustrum activity drives aberrant cognitive network processing in human chronic pain.

Aberrant cognitive network activity and cognitive deficits are established features of chronic pain. However, the nature of cognitive network alterations associated with chronic pain and their underlying mechanisms require elucidation. Here, we report that the claustrum, a subcortical nucleus implicated in cognitive network modulation, is activated by acute painful stimulation and pain-predictive cues in healthy participants.

Sex differences in visceral sensitivity and brain activity in a rat model of comorbid pain: a longitudinal study.

Temporomandibular disorder (TMD) and irritable bowel syndrome (IBS) are 2 chronic overlapping pain conditions (COPCs) that present with significant comorbidity. Both conditions are more prevalent in women and are exacerbated by stress. While peripheral mechanisms might contribute to pain hypersensitivity for each individual condition, mechanisms underlying the comorbidity are poorly understood, complicating pain management when multiple conditions are involved.