A sociocultural neuroscience approach to pain

The Development and Validation of a Measure of Mental Health, Help-Seeking Beliefs in Arabic-Speaking Refugees

Despite reporting elevated rates of posttraumatic stress disorder (PTSD), refugees are less likely than other groups to seek psychological treatment. Relatively little attention has been paid to the role of negative help-seeking beliefs in influencing treatment uptake. The current study sought to develop and psychometrically validate a novel measure indexing negative help-seeking beliefs for refugees (Help-Seeking Beliefs Scale [HSBS]). In this study, 262 Arabic-speaking refugee participants completed an online survey consisting of the HSBS along with measures indexing similar constructs (self-stigma of PTSD and help-seeking, perceived stigma, negative help-seeking attitudes, and help-seeking intentions). Factor analysis revealed a three-factor structure aligning with key themes identified in the literature: (a) Fear of Negative Consequences, (b) Inappropriateness, and (c) Perceived Necessity. The scale demonstrated excellent internal consistency, convergent validity, and predicted reduced help-seeking intentions. Results support the utility of a novel measure capturing a prominent help-seeking barrier in a population with high psychopathology and low treatment uptake.

Pressure algometry in the general adult population: Age and sex differences

Experimental pain studies have revealed inter-individual variations in pain perception that are influenced by age, sex, and country of origin. This study aimed to explore the age and sex differences in pressure pain thresholds within the Iranian general population. To assess the pressure pain thresholds, a handheld pressure algometer was applied bilaterally to the middle fingers of both hands. The participants also completed the short form of the McGill Pain Questionnaire to provide a clinical pain rating. This cross-sectional study included 1610 adult subjects (54.96% female, mean age 40.13 ± 10.18 years). The findings indicated that females generally exhibited lower pain thresholds than males when assessing pain detection and tolerance parameters (P < .001). Females also demonstrated a significant lower pressure thresholds and clinical pain ratings compared with men (P < .001). Additionally, significant differences were observed between age groups in terms of pain detection and tolerance thresholds (P = .02 and P = .03, respectively). However, the interaction between sex and age was not significant. No significant differences in pain detection thresholds were observed between the right and left hand (P = .11). This study underscores the potential utility of algometry as a valuable tool for objectifying pain in the Iranian population.

The causal impact of shared decision making on pain outcomes: Gender matters

This national US study determined the causal impact of shared decision making (SDM) on pain outcomes, including any overall pain and the subcategories of any acute pain and any chronic pain. We additionally examined whether the causal impact of SDM on overall pain is moderated by gender, race-ethnicity, clinician-patient racial-ethnic concordance, and clinician-patient gender concordance. We used national US data from the 2003-2017 Medical Expenditure Panel Survey, which were externally valid to the US national non-institutionalized population, employed a standard measure of shared decision making, and applied an internally-valid two-stage least squares approach that used the peer SDM behavior of similar clinicians as an instrument. The instrument was sufficiently strong and statistically uncorrelated with patient characteristics. We found a large impact of SDM on both female and male chronic pain outcomes, where the effect for females was approximately 50% larger than for males, with a 10 percentage point increase in SDM quality resulted fewer females experiencing chronic pain that interfered with everyday activities (-24.8 percentage points; 95% confidence interval [CI]: 43.3, -6.4) than males (-16.5 percentage points; 95% CI: 32.9, -1.0). We estimated that a 10 percentage point national increase in the SDM index would thus result in 10.1 million fewer females and 5.7 million fewer males in the US experiencing chronic pain that interfered with their daily activities. Policy implications include both increasing the quality of SDM for all patients and educating male patients on the value of SDM.

Harnessing Children's Picture Books to Socialize Children About Pain and Injury: A Qualitative Study

Pain experiences are common during childhood (eg, "everyday" pain, vaccine injections) and are powerful opportunities for children to learn about pain and injury. These experiences likely inform fundamental and life-long beliefs about pain. There is scant research investigating the sociocultural contexts in which children learn about pain and injury. One unexplored context is the shared reading of picture books (eg, between parents/caregivers and children). In this study, we investigated whether shared reading of picture books that included depictions of pain and/or injury prompted parent/caregiver-child interactions. If interactions were observed, we explored what those interactions entailed. Twenty parents/caregivers (8 men, 12 women) and their children (n = 27; 10 boys, 17 girls) were recruited from libraries in South Australia. Parent/caregiver-child families chose from 8 books (7 fiction, 1 nonfiction) with varying amounts of pain/injury-related content. Shared reading interactions were video recorded, transcribed, and analyzed alongside analysis of the picture books using reflexive thematic analysis. Pain/injury-related interactions were observed between parents/caregivers and children during shared reading of picture books. Qualitative analyses generated 1 main theme and 3 subthemes. Findings identified that shared reading presented an opportunity for children's understanding of pain and injury to be socialized through discussion of characters' experiences. This included teaching children about pain and injury, as well as promoting empathy and emotional attunement toward characters who were depicted as being in pain. Finally, parents/caregivers often responded with observable/expressed amusement if pain/injury was depicted in a light-hearted or unrealistic way. Overall, shared reading of picture books presents an untapped opportunity to socialize children about pain and injury. PERSPECTIVE: Shared reading of picture books that have depictions of pain and/or injury can prompt parent/caregiver-child interactions about pain and injury. These interactions present critical opportunities that can be harnessed to promote children's learning of adaptive pain-related concepts and behaviors during a critical developmental period.

Pain neuroscience education for patients with chronic pain: A scoping review from teaching-learning strategies, educational level, and cultural perspective

OBJECTIVE

(1) To identify the characteristics of PNE programs in terms of teaching-learning strategies, session modality, content delivery format, number of sessions, total minutes and instructional support material used in patients with chronic musculoskeletal pain, (2) to describe PNE adaptations for patients with different educational levels or cultural backgrounds, and (3) to describe the influence of the patient's educational level or cultural background on the effects of PNE.

METHODS

The PRISMA guideline for scoping reviews was followed. Nine databases were systematically searched up to July 8, 2023. Articles that examined clinical or psychosocial variables in adults with chronic musculoskeletal pain who received PNE were included.

RESULTS

Seventy-one articles were included. Studies found benefits of PNE through passive/active teaching-learning strategies with group/individual sessions. However, PNE programs presented great heterogeneity and adaptations to PNE were poorly reported. Most studies did not consider educational level and culture in the effects of PNE.

CONCLUSIONS

Despite the large number of studies on PNE and increased interest in this intervention, the educational level and culture are poorly reported in the studies.

PRACTICAL IMPLICATIONS

It is recommended to use passive and/or active teaching-learning strategies provided in individual and/or group formats considering the patient's educational level and culture.

Does pain hurt more in Spanish? The neurobiology of pain among Spanish-English bilingual adults

We previously found Spanish-English bilingual adults reported higher pain intensity when exposed to painful heat in the language of their stronger cultural orientation. Here, we elucidate brain systems involved in language-driven alterations in pain responses. During separate English- and Spanish-speaking fMRI scanning runs, 39 (21 female) bilingual adults rated painful heat intermixed between culturally evocative images and completed sentence reading tasks. Surveys of cultural identity and language use measured relative preference for US-American vs Hispanic culture (cultural orientation). Participants produced higher intensity ratings in Spanish compared to English. Group-level whole-brain differences in pain-evoked activity between languages emerged in somatosensory, cingulate, precuneus and cerebellar cortex. Regions of interest associated with semantic, attention and somatosensory processing showed higher average pain-evoked responses in participants' culturally preferred language, as did expression of a multivariate pain-predictive pattern. Follow-up moderated mediation analyses showed somatosensory activity mediated language effects on pain intensity, particularly for Hispanic oriented participants. These findings relate to distinct ('meddler', 'spotlight' and 'inducer') hypotheses about the nature of language effects on perception and cognition. Knowledge of language influences on pain could improve efficacy of culturally sensitive treatment approaches across the diversity of Hispanic adults to mitigate documented health disparities in this population.

Clinical conversations in the management of chronic musculoskeletal pain in vulnerable patient populations: a meta-ethnography

PURPOSE

The purpose of this meta-ethnography was to synthesize the research exploring patient/provider perceptions of clinical conversations (CC) centered on chronic musculoskeletal pain (CMP) in vulnerable adult populations.

MATERIALS AND METHODS

A systematic search for qualitative/mixed method studies in CINAHL, PubMed, Scopus, Sociology Database in ProQuest, and Web of Science used PRIMSA-P guidelines. Data synthesis used eMERGe guidelines; findings were presented in nested hierarchal theoretical frameworks.

RESULTS

The included studies explored patients' (n = 18), providers' (n = 2), or patients' and providers' perspectives (n = 5) with diversity in patient participants represented (n = 415): immigrants, indigenous people, women, and veterans. Themes for each level of the nested hierarchal models revealed greater complexity in patients' perceptions about the CC in CMP relative to clinicians' perceptions. A unique finding was sociopolitical/historical factors can influence CC for vulnerable populations.

CONCLUSION

The combined nested hierarchical models provided insight into the need for clinicians to be aware of the broader array of influences on the CC. Key themes indicated that improving continuity of care and cultural training are needed to improve the CC. Additionally, due to patients' perception of how healthcare systems' policies influence the CC, patients should be consulted to guide the change needed to improve inequitable outcomes.IMPLICATIONS FOR REHABILITATIONHealthcare providers wishing to improve the clinical conversation in chronic musculoskeletal pain can more broadly explore potential factors influencing patients' experiences and perceptions.Screening during the clinical conversation can include assessing for sociopolitical and historical influences on patients' experiences with chronic musculoskeletal pain.Healthcare providers can explore how to minimize disjointed care in an effort to improve the clinical conversation and outcomes in chronic musculoskeletal pain.Healthcare providers and patients can work together to improve inequitable outcomes for vulnerable adults with chronic musculoskeletal pain.This may include cultural training for healthcare providers that is informed by patients.

Past Adversity Influencing Now (PAIN): perspectives on the impact of temporal language on the persistence of pain

Persistent pain is a significant healthcare issue, often unresponsive to traditional treatments. We argue for incorporating non-biomedical perspectives in understanding pain, promoting more comprehensive solutions. This article explores how language, specifically time-related terms, may affect the persistence (stickiness) of pain. We delve into how language influences one's experience of the world, especially in understanding pain through spatial metaphors. Notably, time perceptions differ across languages and cultures and there is no absolute construct of temporal pain experience. In English, time is viewed linearly as past, present, and future. We introduce a framework called Past Adversity Influencing Now (PAIN) which includes various temporal phases of pain; Past Perfect, Past Imperfect, Present, Future Imperfect, and Future Perfect. We suggest that past negative memories (emotional memory images) can "trap" individuals in a "sticky" pain state. We speculate that the process of diagnosing pain as "chronic" may solidify this "stickiness", drawing from the ancient Greek idea of "logos", where pain communicates a message across time and space needing recognition. Our PAIN framework encourages examining pain through a temporal lens, guiding individuals towards a more positive future.

Depression, Cognition, and Pain: Exploring Individual, Cultural and Country-Level Effects Across Europe

The aim of this paper was to investigate the role of economic (eg, GDP per capita), political (eg, healthcare spending), cultural (country-level aggregates norms) and individual correlates (eg, depression) of pain in a secondary analysis of a sample of 76,000 adults in 19 countries across Europe. The sample was aggregated from 2 waves of the Study of Health, Ageing and Retirement in Europe cohort, using multilevel models with cross-level interactions between individual and country-level effects. While there has been extensive focus on individual risk factors (eg, depression, cognition, BMI), the role of social, political and cultural contextual factors has been relatively underexplored. In addition to replicating well-established individual risk factors (eg, increased depression), we demonstrate that higher levels of depression, chronic pain diagnosis, and collectivism, aggregated at the country-level, are also associated with increased pain severity. There was evidence that these country-level effects moderate the effect of individual correlates of pain. These results contribute to the literature by identifying the importance of broader cultural factors alongside individual psychological indices of pain reporting. PERSPECTIVE: In this study we model how individual, political and cultural factors influence pain in a large cross-national sample. In addition to replicating established individual effects, it shows how cultural (ie, collectivism) and political (eg, GDP, healthcare spending) factors affect individual expressions of pain, and how the cultural and individual factors interact with each other.

Doctor trustworthiness influences pain and its neural correlates in virtual medical interactions

Trust is an important component of the doctor-patient relationship and is associated with improved patient satisfaction and health outcomes. Previously, we reported that patient feelings of trust and similarity toward their clinician predicted reductions in evoked pain in response to painful heat stimulations. In the present study, we investigated the brain mechanisms underlying this effect. We used face stimuli previously developed using a data-driven computational modeling approach that differ in perceived trustworthiness and superimposed them on bodies dressed in doctors' attire. During functional magnetic resonance imaging, participants (n = 42) underwent a series of virtual medical interactions with these doctors during which they received painful heat stimulation as an analogue of a painful diagnostic procedure. Participants reported increased pain when receiving painful heat stimulations from low-trust doctors, which was accompanied by increased activity in pain-related brain regions and a multivariate pain-predictive neuromarker. Findings suggest that patient trust in their doctor may have tangible impacts on pain and point to a potential brain basis for trust-related reductions in pain through the modulation of brain circuitry associated with the sensory-discriminative and affective-motivational dimensions of pain.

Cultural Influence on Nurses' Pain Observations Related to Dementia: An Integrative Review

BACKGROUND

Nurses play a pivotal role in pain observation in people living with dementia. However, currently, there is little understanding of the influence culture may have on the way nurses observe pain experienced by people living with dementia.

AIM

This review explores the influence of culture on nurses... pain observations experienced by people living with dementia.

SETTINGS

Studies were included regardless of the setting (e.g., acute medical care, long-term care, community).

DESIGN

An integrative review.

PARTICIPANTS/SUBJECTS

PubMed, Medline, Psychological Information Database, Cochrane Library, Scopus, Web of Science, Cumulative Index of Nursing and Allied Health Literature, and ProQuest were included in the search.

METHODS

Electronic databases were searched using synonyms for "dementia," "nurse," "culture," and "pain observation." The review included ten primary research papers following the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines.

RESULTS

Nurses reported that pain observation in people living with dementia is challenging. Four themes were identified by data synthesis: (1) using behaviors for pain observation; (2) information from carers for pain observation; (3) pain assessment tools for pain observation; and (4) role of knowledge, experience, and intuition in pain observation.

CONCLUSIONS

There is a limited understanding of the role of culture on nurses' pain observations. However, nurses take a multifaceted approach to observing pain using behaviors, information from carers, pain assessment tools, and their knowledge, experience, and intuition.

Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks-American Pain Society-American Academy of Pain Medicine Pain Taxonomy Diagnostic Criteria for Acute Needle Pain

Needle procedures are among the most common causes of pain and distress for individuals seeking health care. While needle pain is especially problematic for children needle pain and associated fear also has significant impact on adults and can lead to avoidance of appropriate medical care. Currently there is not a standard definition of needle pain. A taxonomy, or classification system, for acute needle pain would aid research efforts and enhance clinical care. To meet this need, the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks public-private partnership with the U.S. Food and Drug Administration, the American Pain Society, and the American Academy of Pain Medicine formed the Analgesic, Anesthetic, and Addiction Clinical Trial Translations, Innovations, Opportunities, and Networks-American Pain Society-American Academy of Pain Medicine Pain Taxonomy initiative. One of the goals of this initiative was to develop taxonomies for acute pain disorders, including needle pain. To accomplish this, a working group of experts in needle pain was convened. Based on available literature and expert opinion, the working group used a 5-dimenional structure (diagnostic criteria, common features, modulating factors, impact and/or functional consequences, and putative mechanisms) to develop an acute pain taxonomy that is specific needle pain. As part of this, a set of 4 diagnostic criteria, with 2 modifiers to account for the influence of needle associated fear, are proposed to define the types of acute needle pain. PERSPECTIVE: This article presents a taxonomy for acute needle pain. This taxonomy could help to standardize definitions of acute pain in clinical studies of patients undergoing needle procedures.

Confronting Racism in All Forms of Pain Research: Reframing Study Designs

This second paper in a 3-part series on antiracism in pain research across the translational spectrum focuses on study design factors. Although objectivity is a cornerstone value of science, subjectivity is embedded in every step of the research process as investigators make choices about who they collaborate with, which research questions they ask, how they recruit participants, which research tools they use, and how they analyze and interpret data. We present theory and evidence from disciplines such as sociology, medical anthropology, statistics, and public health to discuss 4 common study design factors, including 1) the dominant biomedical narrative of pain that restricts funding and exploration of social indicators of pain, 2) low diversity and inclusion in pain research enrollment that restricts generalizability to racialized groups, 3) the use of "race" or "ethnicity" as a statistical variable and proxy for lived experiences (eg, racism, resilience), and 4) limited modeling in preclinical research for the impact of social factors on pain physiology. The information presented in this article is intended to start conversations across stakeholders in the pain field to explore how we can come together to adopt antiracism practices in our work at large to achieve equity for racialized groups. PERSPECTIVE: This is the second paper in a 3-part series on antiracism in pain research. This part identifies common study design factors that risk hindering progress toward pain care equity. We suggest reframes using an antiracism framework for these factors to encourage all pain investigators to collectively make strides toward equity.

Nurses' management of children's acute postoperative pain: A theory of bureaucratic caring deductive study

BACKGROUND

Few studies have examined the translation of nurses' knowledge of pain management into clinical practice or how nurses negotiated the bureaucracy of caring to treat patients' acute pain.

PURPOSE

This study describes factors that influence pediatric nurses' actions in caring for hospitalized children's acute post-surgical pain.

METHOD

Ray's Theory of Bureaucratic Caring provided the theoretical framework for this mixed methods study of ethnography and human factors engineering. Fourteen nurses were observed throughout their shifts (175.5 h) to elucidate humanistic and bureaucratic influences.

FINDINGS

Of 105 pain assessments, nurses intervened with pharmacologic (n = 45) and biobehavioral (n = 13) interventions for pediatric patients' post-surgical pain in less than 11 min; and 25 assessments revealed patients did not have pain. Pain was assessed and no intervention was provided to 4 patients who were asleep, 5 patients who refused, 2 patients who had no ordered analgesics and 10 patients who were assessed prior to peak effectiveness of their prior analgesic. Overall pain was well-controlled. Of the 28 themes identified, the interplay of 6 categorized to the social/cultural humanistic, 7 political, and 6 technologic/physiological bureaucratic dimensions most strongly influenced pain care.

DISCUSSION

To achieve optimal pain care outcomes, nurses' and parents' pain management knowledge was less influential for clinical practice translation than nurses' negotiation of other dimensions of bureaucratic caring.

Culture and musculoskeletal pain: strategies, challenges, and future directions to develop culturally sensitive physical therapy care

BACKGROUND

Pain experience has a multidimensional nature. Assessment and treatment recommendations for pain conditions suggest clinicians use biopsychosocial approaches to treat pain and disability. The current pain research is overwhelmingly skewed towards the study of biological and psychological factors including interventions, whereas, cultural factors are often ignored.

OBJECTIVE

The aims of this Masterclass is threefold: (1) to discuss cultural influences on pain, (2) to provide strategies for delivering appropriate pain education and exercises in culturally diverse people with chronic pain, and (3) to present challenges and future directions to clinicians and researchers.

DISCUSSION

Cultural factors have a relevant influence on the way individuals experience and manage health and illness. Thus, people with different cultural experience perceive, respond, communicate and manage their pain in different ways. In this aspect, the contents of pain education should be presented using different culturally appropriate examples, metaphors, images, and delivery methods that may enhance the impact of the message. Efforts should be made to produce and spread culturally adapted evidence-based materials and resources. In addition, a culturally sensitive approach may help to introduce patients to graded activities, so that they can apply these strategies in culturally acceptable and meaningful ways. Future studies should investigate the effectiveness of culturally-adapted interventions in pain-related outcomes in different pain conditions in patients with different cultural backgrounds.

A social affective neuroscience lens on placebo analgesia

Pain is a fundamental experience that promotes survival. In humans, pain stands at the intersection of multiple health crises: chronic pain, the opioid epidemic, and health disparities. The study of placebo analgesia highlights how social, cognitive, and affective processes can directly shape pain, and identifies potential paths for mitigating these crises. This review examines recent progress in the study of placebo analgesia through affective science. It focuses on how placebo effects are shaped by expectations, affect, and the social context surrounding treatment, and discusses neurobiological mechanisms of placebo, highlighting unanswered questions and implications for health. Collaborations between clinicians and social and affective scientists can address outstanding questions and leverage placebo to reduce pain and improve human health.

The role of self-evaluated pain sensitivity as a mediator of objectively measured pain tolerance in Native Americans: findings from the Oklahoma Study of Native American Pain Risk (OK-SNAP)

Native Americans (NAs) are at increased risk for chronic pain. One mechanism contributing to this pain disparity could be personal pain beliefs, which may influence actual pain sensitivity. Thus, we examined whether self-evaluated pain sensitivity (SEPS) mediates the relationship between ethnicity [NAs vs. non-Hispanic Whites (NHWs)] and objectively-measured pain tolerance, and whether catastrophic thinking and pain-related anxiety influence these pain beliefs. 232 healthy, pain-free NAs and NHWs completed questionnaires measuring SEPS, catastrophizing, and anxiety. Objective pain tolerance was also assessed. Results suggested: (1) NAs reported higher levels of SEPS, catastrophizing, and anxiety, (2) catastrophizing may have enhanced anxiety and both catastrophizing and anxiety were associated with higher SEPS, and (3) anxiety and SEPS were associated with lower pain tolerance. A significant bootstrapped mediation analysis suggested NAs experienced higher pain-related anxiety, which may have promoted higher SEPS, that in turn reduced pain tolerance. Longitudinal research is needed to confirm this.

What is pain: Are cognitive and social features core components?

Pain is a universal experience, but it has been challenging to adequately define. The revised definition of pain recently published by the International Association for the Study of Pain addressed important shortcomings of the previous version; however, it remains narrow in its focus on sensory and emotional features of pain, failing to capture the substantial roles of cognitive and social core components of the experience and their importance to advances in pain management. This paper reviews evidence and theoretical models for the significant role social and cognitive factors play in pain experience and we argue that without explicit recognition of these core components in the definition, significant nuances are lost at a cost to understanding and clinical management of pain. A focus on sensory and emotional features perpetuates biomedical interventions and research, whereas recognition of cognitive and social features supports a multidimensional model of pain, advances in interdisciplinary care, and the benefits of cognitive behavioral therapy and self‐management interventions. We also explore the six Key Notes that accompany the new definition of pain, discuss their application to the understanding of pain in childhood, and, in doing so, further explore social and cognitive implications. Considerations are also described for assessment and treatment of pain in pediatric populations.

Clinician-Patient Racial/Ethnic Concordance Influences Racial/Ethnic Minority Pain: Evidence from Simulated Clinical Interactions

OBJECTIVE

Racial and ethnic minorities in the United States report higher levels of both clinical and experimental pain, yet frequently receive inadequate pain treatment. Although these disparities are well documented, their underlying causes remain largely unknown. Evidence from social psychological and health disparities research suggests that clinician-patient racial/ethnic concordance may improve minority patient health outcomes. Yet whether clinician-patient racial/ethnic concordance influences pain remains poorly understood.

METHODS

Medical trainees and community members/undergraduates played the role of "clinicians" and "patients," respectively, in simulated clinical interactions. All participants identified as non-Hispanic Black/African American, Hispanic white, or non-Hispanic white. Interactions were randomized to be either racially/ethnically concordant or discordant in a 3 (clinician race/ethnicity) × 2 (clinician-patient racial/ethnic concordance) factorial design. Clinicians took the medical history and vital signs of the patient and administered an analogue of a painful medical procedure.

RESULTS

As predicted, clinician-patient racial/ethnic concordance reduced self-reported and physiological indicators of pain for non-Hispanic Black/African American patients and did not influence pain for non-Hispanic white patients. Contrary to our prediction, concordance was associated with increased pain report in Hispanic white patients. Finally, the influence of concordance on pain-induced physiological arousal was largest for patients who reported prior experience with or current worry about racial/ethnic discrimination.

CONCLUSIONS

Our findings inform our understanding of the sociocultural factors that influence pain within medical contexts and suggest that increasing minority, particularly non-Hispanic Black/African American, physician numbers may help reduce persistent racial/ethnic pain disparities.

Ethnic disparities in pain processing among healthy adults: μ-opioid receptor binding potential as a putative mechanism

Although ethnic differences in pain perception are well documented, the underlying mechanism for these outcomes has not been established. µ-opioid receptor (MOR) function might contribute to this disparity, given that MORs play a key role in pain sensitivity and modulation. However, no study has characterized ethnic differences in MOR physiology. This study sought to address this knowledge gap by examining differences in µ-selective agonist binding potential (BPND; [C]-Carfentanil) between 27 non-Hispanic black (NHB) and 27 demographically similar, non-Hispanic white participants. Participants completed questionnaires and two 90-minute high-resolution research tomograph positron emission tomography (PET) imaging sessions. During PET imaging, a capsaicin or control cream was applied to individuals' arms, and pain ratings were collected. Bonferroni-corrected PET volumes of interest analyses revealed significantly greater [C]-Carfentanil BPND among NHB participants in bilateral ventral striatum ([left]: F1,52 = 16.38, P < 0.001; [right]: F1,52 = 21.76, P < 0.001), bilateral dorsolateral prefrontal cortex ([left] F1,52 = 17.3, P < 0.001; [right]: F1,52 = 14.17, P < 0.001), bilateral subgenual anterior cingulate cortex ([left]: F1,52 = 10.4, P = 0.002; [right]: F1,52 = 12.91, P = 0.001), and right insula (F1,52 = 11.0, P = 0.002). However, there were no significant main effects of condition or ethnicity × condition interaction effects across models, likely attributable to individual variability in the direction of change within groups. BPND values were significantly correlated with pain ratings collected during the capsaicin condition (r range = 0.34-0.46, P range = 0.01-0.001). Results suggest that NHB individuals might have generally greater unoccupied MOR density than non-Hispanic white peers. Findings have implications for physiological differences underlying ethnicity-related pain disparities. If replicated, these results further emphasize the need for tailored treatments in historically underserved populations.

Effects of Language Context and Cultural Identity on the Pain Experience of Spanish-English Bilinguals

While language and culture influence cognition, their role in shaping pain remains understudied. We tested whether language and cultural identification influence pain report among Spanish-English bilinguals. Eighty bilingual Hispanics/Latinos (40 female) experienced painful thermal stimulations, providing pain intensity and unpleasantness ratings, on separate English and Spanish testing days. Participants' skin conductance responses (SCRs) during stimulations served as measures of physiological arousal. Bilingual participants showed larger SCRs and higher pain intensity when speaking the language congruent with their dominant cultural identification. That is, those endorsing more Hispanic cultural identification showed higher pain in Spanish, while US-American-dominant participants demonstrated increased pain in English. Follow-up moderated mediation demonstrated that SCRs mediated language effects on pain ratings for participants endorsing greater Hispanic cultural identification. Together, our results suggest language, cultural associations, and bodily arousal synergistically influence pain evaluations among bilingual people, potentially contributing to well-documented health disparities between Hispanic and non-Hispanic communities.

Discovery and validation of biomarkers to aid the development of safe and effective pain therapeutics: challenges and opportunities

Pain medication plays an important role in the treatment of acute and chronic pain conditions, but some drugs, opioids in particular, have been overprescribed or prescribed without adequate safeguards, leading to an alarming rise in medication-related overdose deaths. The NIH Helping to End Addiction Long-term (HEAL) Initiative is a trans-agency effort to provide scientific solutions to stem the opioid crisis. One component of the initiative is to support biomarker discovery and rigorous validation in collaboration with industry leaders to accelerate high-quality clinical research into neurotherapeutics and pain. The use of objective biomarkers and clinical trial end points throughout the drug discovery and development process is crucial to help define pathophysiological subsets of pain, evaluate target engagement of new drugs and predict the analgesic efficacy of new drugs. In 2018, the NIH-led Discovery and Validation of Biomarkers to Develop Non-Addictive Therapeutics for Pain workshop convened scientific leaders from academia, industry, government and patient advocacy groups to discuss progress, challenges, gaps and ideas to facilitate the development of biomarkers and end points for pain. The outcomes of this workshop are outlined in this Consensus Statement.

Neural and sociocultural mediators of ethnic differences in pain

Understanding ethnic differences in pain is important for addressing disparities in pain care. A common belief is that African Americans are hyposensitive to pain compared to Whites, but African Americans show increased pain sensitivity in clinical and laboratory settings. The neurobiological mechanisms underlying these differences are unknown. We studied an ethnicity- and gender-balanced sample of African Americans, Hispanics and non-Hispanic Whites using functional magnetic resonance imaging during thermal pain. Higher pain report in African Americans was mediated by discrimination and increased frontostriatal circuit activations associated with pain rating, discrimination, experimenter trust and extranociceptive aspects of pain elsewhere. In contrast, the neurologic pain signature, a neuromarker sensitive and specific to nociceptive pain, mediated painful heat effects on pain report largely similarly in African American and other groups. Findings identify a brain basis for higher pain in African Americans related to interpersonal context and extranociceptive central pain mechanisms and suggest that nociceptive pain processing may be similar across ethnicities.

Improving Practices for Selecting a Subset of Important Predictors in Psychology: An Application to Predicting Pain

Frequently, researchers in psychology are faced with the challenge of narrowing down a large set of predictors to a smaller subset. There are a variety of ways to do this, but commonly it is done by choosing predictors with the strongest bivariate correlations with the outcome. However, when predictors are correlated, bivariate relationships may not translate into multivariate relationships. Further, any attempts to control for multiple testing are likely to result in extremely low power. Here we introduce a Bayesian variable-selection procedure frequently used in other disciplines, stochastic search variable selection (SSVS). We apply this technique to choosing the best set of predictors of the perceived unpleasantness of an experimental pain stimulus from among a large group of sociocultural, psychological, and neurobiological (functional MRI) individual-difference measures. Using SSVS provides information about which variables predict the outcome, controlling for uncertainty in the other variables of the model. This approach yields new, useful information to guide the choice of relevant predictors. We have provided Web-based open-source software for performing SSVS and visualizing the results.

Placebo Effects on the Neurologic Pain Signature: A Meta-analysis of Individual Participant Functional Magnetic Resonance Imaging Data

Importance

Placebo effects reduce pain and contribute to clinical analgesia, but after decades of research, it remains unclear whether placebo treatments mainly affect nociceptive processes or other processes associated with pain evaluation.

Objective

We conducted a systematic, participant-level meta-analysis to test the effect of placebo treatments on pain-associated functional neuroimaging responses in the neurologic pain signature (NPS), a multivariate brain pattern tracking nociceptive pain.

Data Sources

Medline (PubMed) was searched from inception to May 2015; the search was augmented with results from previous meta-analyses and expert recommendations.

Study Selection

Eligible studies were original investigations that were published in English in peer-reviewed journals and that involved functional neuroimaging of the human brain with evoked pain delivered under stimulus intensity-matched placebo and control conditions. The authors of all eligible studies were contacted and asked to provide single-participant data.

Data Extraction and Synthesis

Data were collected between December 2015 and November 2017 following the Preferred Reporting Items for Systematic Review and Meta-Analyses of individual participant data guidelines. Results were summarized across participants and studies in a random-effects model.

Main Outcomes and Measures

The main, a priori outcome was NPS response; pain reports were assessed as a secondary outcome.

Results

We obtained data from 20 of 28 identified eligible studies, resulting in a total sample size of 603 healthy individuals. The NPS responses to painful stimulation compared with baseline conditions were positive in 575 participants (95.4%), with a very large effect size (g = 2.30 [95% CI, 1.92 to 2.69]), confirming its sensitivity to nociceptive pain in this sample. Placebo treatments showed significant behavioral outcomes on pain ratings in 17 of 20 studies (85%) and in the combined sample (g = -0.66 [95% CI, -0.80 to -0.53]). However, placebo effects on the NPS response were significant in only 3 of 20 studies (15%) and were very small in the combined sample (g = -0.08 [95% CI, -0.15 to -0.01]). Similarly, analyses restricted to studies with low risk of bias (g = -0.07 [95% CI, -0.15 to 0.00]) indicated very small effects, and analyses of just placebo responders (g = -0.22 [95% CI, -0.34 to -0.11]) indicated small effects, as well.

Conclusions and Relevance

Placebo treatments have moderate analgesic effects on pain reports. The very small effects on NPS, a validated measure that tracks levels of nociceptive pain, indicate that placebo treatments affect pain via brain mechanisms largely independent of effects on bottom-up nociceptive processing.

Medical anthropology and symbolic cure: from the placebo to cultures of meaningful healing

The perspectives of medical anthropology on symbolic cure are crucial for understanding placebo mechanisms on the medical agenda. However, while classic biomedical conceptions of the placebo discredited cultural factors as legitimate therapeutic tools, the anthropological critical approach confronted this perspective in the opposite way, rejecting the role of neurobiological factors, and using culture as a self-contained phenomenon. This manuscript is a review of the symbolic healing, stressing the importance of an integrated and interdisciplinary study of the placebo response, and the need to go beyond both biological and cultural reductionisms. Various perspectives from medical anthropology will be described, ranging from classical to multilevel perspectives that enable consideration of the placebo in its neurobiological, psychological and cultural dimensions.

Brain systems at the intersection of chronic pain and self-regulation

Chronic pain is a multidimensional experience with cognitive, affective, and somatosensory components that can be modified by expectations and learning. Individual differences in cognitive and affective processing, as well as contextual aspects of the pain experience, render chronic pain an inherently personal experience. Such individual differences are supported by the heterogeneity of brain representations within and across chronic pain pathologies. In this review, we discuss the complexity of brain representations of pain, and, with respect to this complexity, identify common elements of network-level disruptions in chronic pain. Specifically, we identify prefrontal-limbic circuitry and the default mode network as key elements of functional disruption. We then discuss how these disrupted circuits can be targeted through self-regulation and related cognitive strategies to alleviate chronic pain. We conclude with a proposal for how to develop personalized multivariate models of pain representation in the brain and target them with real-time neurofeedback, so that patients can explore and practice self-regulatory techniques with maximal efficiency.