A multistudy analysis reveals that evoked pain intensity representation is distributed across brain systems.

Information is coded in the brain at multiple anatomical scales: locally, distributed across regions and networks, and globally. For pain, the scale of representation has not been formally tested, and quantitative comparisons of pain representations across regions and networks are lacking. In this multistudy analysis of 376 participants across 11 studies, we compared multivariate predictive models to investigate the spatial scale and location of evoked heat pain intensity representation. We compared models based on (a) a single most pain-predictive region or resting-state network; (b) pain-associated cortical-subcortical systems developed from prior literature ("multisystem models"); and (c) a model spanning the full brain. We estimated model accuracy using leave-one-study-out cross-validation (CV; 7 studies) and subsequently validated in 4 independent holdout studies. All spatial scales conveyed information about pain intensity, but distributed, multisystem models predicted pain 20% more accurately than any individual region or network and were more generalizable to multimodal pain (thermal, visceral, and mechanical) and specific to pain. Full brain models showed no predictive advantage over multisystem models. These findings show that multiple cortical and subcortical systems are needed to decode pain intensity, especially heat pain, and that representation of pain experience may not be circumscribed by any elementary region or canonical network. Finally, the learner generalization methods we employ provide a blueprint for evaluating the spatial scale of information in other domains.

The neural signature of the decision value of future pain.

Pain is a primary driver of action. We often must voluntarily accept pain to gain rewards. Conversely, we may sometimes forego potential rewards to avoid associated pain. In this study, we investigated how the brain represents the decision value of future pain. Participants (n = 57) performed an economic decision task, choosing to accept or reject offers combining various amounts of pain and money presented visually. Functional MRI (fMRI) was used to measure brain activity throughout the decision-making process. Using multivariate pattern analyses, we identified a distributed neural representation predicting the intensity of the potential future pain in each decision and participants' decisions to accept or avoid pain. This neural representation of the decision value of future pain included negative weights located in areas related to the valuation of rewards and positive weights in regions associated with saliency, negative affect, executive control, and goal-directed action. We further compared this representation to future monetary rewards, physical pain, and aversive pictures and found that the representation of future pain overlaps with that of aversive pictures but is distinct from experienced pain. Altogether, the findings of this study provide insights on the valuation processes of future pain and have broad potential implications for our understanding of disorders characterized by difficulties in balancing potential threats and rewards.

Key Age-Friendly Components of Municipalities that Foster Social Participation of Aging Canadians: Results from the Canadian Longitudinal Study on Aging.

Municipalities can foster the social participation of aging adults. Although making municipalities age-friendly is recognized as a promising way to help aging adults stay involved in their communities, little is known about the key components (e.g., services and structures) that foster social participation. This study thus aimed to identify key age-friendly components (AFC) best associated with the social participation of older Canadians. Secondary analyses were carried out using baseline data from the Canadian Longitudinal Study on Aging (n = 25,411) in selected municipalities (m = 110 with ≥ 30 respondents), the Age-friendly Survey, and census data. Social participation was estimated based on the number of community activities outside the home per month. AFC included housing, transportation, outdoor spaces and buildings, safety, recreation, workforce participation, information, respect, health, and community services. Multilevel models were used to examine the association between individual social participation, key AFC, and environmental characteristics, while controlling for individual characteristics. Aged between 45 and 89, half of the participants were women who were engaged in 20.2±12.5 activities per month. About 2.5% of the variance in social participation was attributable to municipalities. Better outdoor spaces and buildings (p < 0.001), worse communication and information (p < 0.01), and lower material deprivation (p < 0.001) were associated with higher social participation. Age was the only individual-level variable to have a significant random effect, indicating that municipal contexts may mediate its impact with social participation. This study provides insights to help facilitate social participation and promote age-friendliness, by maintaining safe indoor and outdoor mobility, and informing older adults of available activities.

Genome-wide analysis identifies impaired axonogenesis in chronic overlapping pain conditions.

Chronic pain is often present at more than one anatomical location, leading to chronic overlapping pain conditions. Whether chronic overlapping pain conditions represent a distinct pathophysiology from the occurrence of pain at only one site is unknown. Using genome-wide approaches, we compared genetic determinants of chronic single-site versus multisite pain in the UK Biobank. We found that different genetic signals underlie chronic single-site and multisite pain with much stronger genetic contributions for the latter. Among 23 loci associated with multisite pain, nine loci replicated in the HUNT cohort, with the DCC netrin 1 receptor (DCC) as the top gene. Functional genomics identified axonogenesis in brain tissues as the major contributing pathway to chronic multisite pain. Finally, multimodal structural brain imaging analysis showed that DCC is most strongly expressed in subcortical limbic regions and is associated with alterations in the uncinate fasciculus microstructure, suggesting that DCC-dependent axonogenesis may contribute to chronic overlapping pain conditions via corticolimbic circuits.

Heterogeneous Cortical Effects of Spinal Cord Stimulation.

OBJECTIVES: The understanding of the cortical effects of spinal cord stimulation (SCS) remains limited. Multiple studies have investigated the effects of SCS in resting-state electroencephalography. However, owing to the large variation in reported outcomes, we aimed to describe the differential cortical responses between two types of SCS and between responders and nonresponders using magnetoencephalography (MEG). MATERIALS AND METHODS: We conducted 5-minute resting-state MEG recordings in 25 patients with chronic pain with active SCS in three sessions, each after a one-week exposure to tonic, burst, or sham SCS. We extracted six spectral features from the measured neurophysiological signals: the alpha peak frequency; alpha power ratio (power 7-9 Hz/power 9-11 Hz); and average power in the theta (4-7.5 Hz), alpha (8-12.5 Hz), beta (13-30 Hz), and low-gamma (30.5-60 Hz) frequency bands. We compared these features (using nonparametric permutation t-tests) for MEG sensor and cortical map effects across stimulation paradigms, between participants who reported low (< 5, responders) vs high (≥ 5, nonresponders) pain scores, and in three representative participants. RESULTS: We found statistically significant (p < 0.05, false discovery rate corrected) increased MEG sensor signal power below 3 Hz in response to burst SCS compared with tonic and sham SCS. We did not find statistically significant differences (all p > 0.05) between the power spectra of responders and nonresponders. Our data did not show statistically significant differences in the spectral features of interest among the three stimulation paradigms or between responders and nonresponders. These results were confirmed by the MEG cortical maps. However, we did identify certain trends in the MEG source maps for all comparisons and several features, with substantial variation across participants. CONCLUSIONS: The considerable variation in cortical responses to the various SCS treatment options necessitates studies with sample sizes larger than commonly reported in the field and more personalized treatment plans. Studies with a finer stratification between responders and nonresponders are required to advance the knowledge on SCS treatment effects.

Factors Associated with Complicated Grief Following a Railway Tragedy.

On July 6, 2013, a train with 72 crude oil tank cars derailed in the heart of Lac-Mégantic, a small municipality of 6,000 inhabitants located in Québec (Canada). This tragedy killed 47 people. Technological disasters are rarely studied in bereavement research, and train derailments even less. The goal of this article is to increase our understanding of the bereavement consequences of technological disasters. Specifically, we aim to identify the factors that lead to the experience complicated grief and distinguish from the protective factors. A representative population-based survey was conducted among 268 bereaved people, three and a half years after the train accident. Of these, 71 people (26.5%) experienced complicated grief. People with complicated grief (CG) differ significantly from those without CG in terms of psychological health, perception of physical health, alcohol use and medication, as well as social and professional relationships. Hierarchical logistic regression analysis identified four predictive factors for CG: level of exposure to the disaster, having a negative perception of the event, as well as having a paid job and low-income increase the risk of CG. The importance of having health and social practitioners pay attention to these factors of CG are discussed along with future directions for research.

Effect sizes and test-retest reliability of the fMRI-based neurologic pain signature.

Identifying biomarkers that predict mental states with large effect sizes and high test-retest reliability is a growing priority for fMRI research. We examined a well-established multivariate brain measure that tracks pain induced by nociceptive input, the Neurologic Pain Signature (NPS). In N = 295 participants across eight studies, NPS responses showed a very large effect size in predicting within-person single-trial pain reports (d = 1.45) and medium effect size in predicting individual differences in pain reports (d = 0.49). The NPS showed excellent short-term (within-day) test-retest reliability (ICC = 0.84, with average 69.5 trials/person). Reliability scaled with the number of trials within-person, with ≥60 trials required for excellent test-retest reliability. Reliability was tested in two additional studies across 5-day (N = 29, ICC = 0.74, 30 trials/person) and 1-month (N = 40, ICC = 0.46, 5 trials/person) test-retest intervals. The combination of strong within-person correlations and only modest between-person correlations between the NPS and pain reports indicate that the two measures have different sources of between-person variance. The NPS is not a surrogate for individual differences in pain reports but can serve as a reliable measure of pain-related physiology and mechanistic target for interventions.

Multiple Brain Networks Mediating Stimulus-Pain Relationships in Humans.

The brain transforms nociceptive input into a complex pain experience comprised of sensory, affective, motivational, and cognitive components. However, it is still unclear how pain arises from nociceptive input and which brain networks coordinate to generate pain experiences. We introduce a new high-dimensional mediation analysis technique to estimate distributed, network-level patterns that formally mediate the relationship between stimulus intensity and pain. We applied the model to a large-scale analysis of functional magnetic resonance imaging data (N = 284), focusing on brain mediators of the relationship between noxious stimulus intensity and trial-to-trial variation in pain reports. We identify mediators in both traditional nociceptive pathways and in prefrontal, midbrain, striatal, and default-mode regions unrelated to nociception in standard analyses. The whole-brain mediators are specific for pain versus aversive sounds and are organized into five functional networks. Brain mediators predicted pain ratings better than previous brain measures, including the neurologic pain signature (Wager et al. 2013). Our results provide a broader view of the networks underlying pain experience, as well as novel brain targets for interventions.

Pain-Evoked Reorganization in Functional Brain Networks.

Recent studies indicate that a significant reorganization of cerebral networks may occur in patients with chronic pain, but how immediate pain experience influences the organization of large-scale functional networks is not yet well characterized. To investigate this question, we used functional magnetic resonance imaging in 106 participants experiencing both noxious and innocuous heat. Painful stimulation caused network-level reorganization of cerebral connectivity that differed substantially from organization during innocuous stimulation and standard resting-state networks. Noxious stimuli increased somatosensory network connectivity with (a) frontoparietal networks involved in context representation, (b) "ventral attention network" regions involved in motivated action selection, and (c) basal ganglia and brainstem regions. This resulted in reduced "small-worldness," modularity (fewer networks), and global network efficiency and in the emergence of an integrated "pain supersystem" (PS) whose activity predicted individual differences in pain sensitivity across 5 participant cohorts. Network hubs were reorganized ("hub disruption") so that more hubs were localized in PS, and there was a shift from "connector" hubs linking disparate networks to "provincial" hubs connecting regions within PS. Our findings suggest that pain reorganizes the network structure of large-scale brain systems. These changes may prioritize responses to painful events and provide nociceptive systems privileged access to central control of cognition and action during pain.

The Stressful Characteristics of Pain That Drive You NUTS: A Qualitative Exploration of a Stress Model to Understand the Chronic Pain Experience.

OBJECTIVE: Despite decades of research on the identification of specific characteristics of situations that trigger a physiological stress response (novelty, unpredictability, threat to the ego, and sense of low control [NUTS]), no integrative research has examined the validity of this framework applied to pain experiences. This study aimed to 1) explore the stressful characteristics of pain among individuals living with chronic pain and 2) examine whether the NUTS framework comprehensively captures the stressful nature of pain. SUBJECTS: Participants were 41 adult participants living with chronic pain. METHODS: Interviews in six focus groups were conducted in French using a semistructured interview guide. Participants first discussed how pain is stressful. Then, they were introduced to the NUTS framework and commented on the extent to which it captured their experience. The verbatim transcriptions of interviews were reviewed using reflexive thematic analysis. Analyses were conducted in French; quotes and themes were translated into English by a professional translator. RESULTS: The pain-NUTS framework adequately captured participants' experiences. Multiple aspects of pain (pain intensity fluctuations, pain flare-up duration, pain quality and location, functional limitations, diagnosis and treatment) were associated with one or more stress-inducing characteristics. In addition, a second layer of meaning emerged in the context of chronic pain that provided contextual information regarding when, how, and why pain became more or less stressful. CONCLUSIONS: The NUTS characteristics seem to offer a comprehensive framework to understand how pain and its context of chronicity can be a source of stress. This study provides preliminary support for the pain-NUTS framework to allow the formal integration of pain and stress research.

Communication strategies and media discourses in the age of COVID-19: an urgent need for action.

Identified in December 2019 in China, the coronavirus 2019 (COVID-19) has been declared a Public Health Emergency of International Concern (PHEIC). Pandemics share features that increase fear. While some fear can stimulate preventive health behaviors, extreme fear can lead to adverse psychological and behavioral response. The media play a major role shaping these responses. When dealing with a PHEIC, the authorities' communication strategies are embedded in a multilevel governance and a highly hierarchal system, which adds another layer of complexity. Carrying out more 'real-world research' is crucial to generate evidence relating to the psychosocial and behavioral aspects involved during the COVID-19 pandemic and how it is shaped by authorities and media discourses. Interdisciplinary research and international collaborations could contribute to improve our understanding and management of risk information. Emerging from a socio-ecological perspective, future research must integrate multilevel analytical elements, to ensure triangulation of evidence and co-constructing robust recommendations. A mixed-method approach should be privileged to address these issues. At the micro-level, a population-based survey could be conducted in various jurisdictions to assess and compare psychosocial issues according to sociocultural groups. Then, a quantitative/qualitative discourse analysis of the media could be performed. Finally, a network analysis could allow assessing how official information flows and circulates across levels of governance. The COVID-19 represents an opportunity to evaluate the impacts of information/communication strategy and misinformation on various cultural and socioeconomic groups, providing important lessons that could be applied to future health emergencies and disasters.

Distinct fMRI patterns colocalized in the cingulate cortex underlie the after-effects of cognitive control on pain.

Demanding tasks can influence following behaviors but the underlying mechanisms remain largely unclear. In the present functional magnetic resonance imaging (fMRI) study, we used multivariate pattern analyses (MVPA) to compare patterns of brain activity associated with pain in response to noxious stimuli administered after a task requiring cognitive control (Stroop) and evaluate their functional interaction based on a mediation analysis model. We found that performing a difficult cognitive task leads to subsequent increases in pain and pain-related multivariate responses across the brain and within the anterior mid-cingulate cortex (aMCC). Moreover, an aMCC pattern predictive of task performance was further reactivated during pain and predicted ensuing increases in pain-related brain responses. This suggests functional interactions between distinct but partly co-localized neural networks underlying executive control and pain. These findings offer a new perspective on the functional role of the cingulate cortex in pain and cognition and provide a promising framework to investigate dynamical interactions between partly overlapping brain networks.

Barriers and Facilitators to Implementing Community Outreach Work, and Inter-professional Collaboration with Regional Partners.

Community outreach workers support individuals in accessing the health and community services they require through various forms of proximity approaches. Even though community outreach has been available in the province of Quebec (Canada) for the past 40 years, it is still difficult to implement and sustain, especially with families of young children. The aim of this study was to document barriers and facilitators to implementing community outreach practices, and to describe how such workers collaborate with sectoral (e.g. health care) and inter-sectoral (e.g. municipalities, community organizations, schools) partners. We performed a content analysis on 55 scientific and grey literature documents, and transcriptions of 24 individual interviews and 3 focus groups with stakeholders including parents, community outreach workers, health care employees, and inter-sectoral partners. This study reveals four categories of barriers and facilitators to the implementation of community outreach work (i.e. organizational factors, nature of the work and worker-related factors, family-related factors, external factors). With regards to collaboration, community outreach workers deal with various partners. Good inter-professional collaboration is achieved through positive interactions and communication, shared or co-developed activities for the families, co-intervention with families, and strategies to enhance role awareness and inter-sectoral meetings. Results highlighted that many factors interact and can either influence, positively or negatively, the opportunity to implement community outreach work. The collaborative practices identified may help to maximize facilitators and overcome barriers. Advocacy and a better understanding of how to integrate community outreach work within health services while maintaining the workers' flexibility are needed to sustain this practice.

The Tampa Scale of Kinesiophobia: Structural Validation among Adolescents with Idiopathic Scoliosis Undergoing Spinal Fusion Surgery.

AIMS: Spinal fusion surgery is one of the most invasive orthopedic surgeries. Pain while moving or a fear of experiencing pain after surgery may delay return to function and cause prolonged disability. The purpose of the study was to examine the psychometric properties of the Tampa Scale of Kinesiophobia (TSK) in pediatric patients undergoing scoliosis surgery. METHODS: Fifty-five adolescents (10-18 years old) scheduled for spinal fusion surgery were enrolled. Participants completed the TSK questionnaire before surgery and six weeks after surgery. Reliability, exploratory and confirmatory factor analyses were performed on the two-factors TSK including activity avoidance (TSK-AA) and somatic focus (TSK-SF). RESULTS: Before and after surgery, all TSK-AA items conformed into the same factor component and revealed good internal reliability with Cronbach's alpha of .76 and .70 respectively. TSK-SF items were separated into different factor components and revealed poor reliability (.11 and .56). The TSK-AA also produced an adequate fit to the data, as reflected with several fit indices at both timepoints, respectively: χ2/df = 1.19 and 1.22; CFI=.96 and .94; and RMSEA=.06 and .06. CONCLUSIONS: The TSK-AA demonstrated good psychometric properties in patients undergoing scoliosis surgery, which provides empirical evidence for pediatrics. Its validation in distinct populations and settings is recommended prior to its use.

Better care through an optimized mental health services continuum (Eastern Townships, Québec, Canada): A systematic and multisource literature review.

INTRODUCTION: In 2014, the health authorities of the Eastern Townships (Québec, Canada) commissioned an evaluation of the mental health admission system for adults (GASMA) to identify the best GASMA organizational or structural elements and optimize the mental health services continuum. METHODS: To develop better services, seven indicators (ie, accessibility to services, integration of levels of services, user satisfaction, guidance and management time, evaluation tools, professional composition, and interprofessional collaboration) were examined through four evaluation questions. A three-step systematic and multisource evaluation was realized. A systematic review of the scientific and gray literature was performed. This evaluation also included key informant opinions to contextualize results from this review. RESULTS: Results from 91 scientific articles, 40 gray literature documents, and 10 interviews highlighted determinants and barriers associated with the examined indicators. From these results, 24 preliminary recommendations were formulated and discussed in a steering committee. These recommendations were then weighted and validated. This served to formulate three final recommendations. CONCLUSION: To optimize the regional mental health services continuum, stakeholders should (1) implement a single-window access for adults with mental health needs, (2) develop alternative services based on users' needs, and (3) test the effectiveness of new methods, initiatives, and tools.

Reduced Fear-Conditioned Pain Modulation in Experienced Meditators: A Preliminary Study.

OBJECTIVE: Mindfulness-based practice is a form of cognitive/affective training that may help reduce suffering by attenuating maladaptive anticipatory processes. This study's objective was to examine the pain modulating impact of classical fear learning in meditation practitioners. METHODS: The hyperalgesic effects of pain expectation and uncertainty were assessed outside formal meditation in 11 experienced meditators (>1000 hours) compared with meditation-naive controls during a Pavlovian classical fear-conditioning paradigm involving two visual stimuli (CS+/CS-), one of which (CS+) co-terminated with a noxious electrical stimulus (unconditioned stimulus) on 50% of trials. A Rescorla-Wagner/Pearce-Hall hybrid model was fitted onto the conditioned skin conductance responses using computational modeling to estimate two learning parameters: expected shock probability and associability (i.e., uncertainty). RESULTS: Using a scale ranging between 0 (no pain) and 100 (extremely painful), meditators reported less pain (M = 19.9, SE = 5.1 for meditators, M = 32.4, SE = 2.4 for controls) but had comparable spinal motor responses (nociceptive flexion reflex) to the unconditioned stimulus. Multilevel mediation analyses revealed that meditators also exhibited reduced hyperalgesic effects of fear learning on higher-order pain responses but comparable effects on the nociceptive flexion reflex. These results suggest that mindfulness affects higher-order perceptual processes to a greater extent than from descending inhibitory controls. Furthermore, meditators showed reduced hyperalgesic effects of fear conditioning with no significant group difference in conditioned learning as evidenced by discriminative anticipatory skin conductance responses and learning parameters derived from computational modeling. CONCLUSIONS: These results highlight potential mechanisms underlying mindfulness-related hypoalgesia, relevant to clinical conditions in which repeated pain exposure might reinforce hyperalgesic processes through fear conditioning.

Distinct brain systems mediate the effects of nociceptive input and self-regulation on pain.

Cognitive self-regulation can strongly modulate pain and emotion. However, it is unclear whether self-regulation primarily influences primary nociceptive and affective processes or evaluative ones. In this study, participants engaged in self-regulation to increase or decrease pain while experiencing multiple levels of painful heat during functional magnetic resonance imaging (fMRI) imaging. Both heat intensity and self-regulation strongly influenced reported pain, but they did so via two distinct brain pathways. The effects of stimulus intensity were mediated by the neurologic pain signature (NPS), an a priori distributed brain network shown to predict physical pain with over 90% sensitivity and specificity across four studies. Self-regulation did not influence NPS responses; instead, its effects were mediated through functional connections between the nucleus accumbens and ventromedial prefrontal cortex. This pathway was unresponsive to noxious input, and has been broadly implicated in valuation, emotional appraisal, and functional outcomes in pain and other types of affective processes. These findings provide evidence that pain reports are associated with two dissociable functional systems: nociceptive/affective aspects mediated by the NPS, and evaluative/functional aspects mediated by a fronto-striatal system.

Looking for capacities rather than vulnerabilities: The moderating effect of health assets on the associations between adverse social position and health.

To increase capacities and control over health, it is necessary to foster assets (i.e. factors enhancing abilities of individuals or communities). Acting as a buffer, assets build foundations for overcoming adverse conditions and improving health. However, little is known about the distribution of assets and their associations with social position and health. In this study, we documented the distribution of health assets and examined whether these assets moderate associations between adverse social position and self-reported health. A representative population-based cross-sectional survey of adults in the Eastern Townships, Quebec, Canada (n = 8737) was conducted in 2014. Measures included assets (i.e. resilience, sense of community belonging, positive mental health, social participation), self-reported health (i.e. perceived health, psychological distress), and indicators of social position. Distribution of assets was studied in relation to gender and social position. Logistic regressions examined whether each asset moderated associations between adverse social position and self-reported health. Different distributions of assets were observed with different social positions. Women were more likely to participate in social activities while men were more resilient. Resilience and social participation were moderators of associations between adverse social position (i.e. living alone, lower household income) and self-reported health. Having assets contributes to better health by increasing capacities. Interventions that foster assets and complement current public health services are needed, especially for people in unfavorable situations. Health and social services decision-makers and practitioners could use these findings to increase capacities and resources rather than focusing primarily on preventing diseases and reducing risk factors.

[Evaluation of implementation of a local consultation model in health and social services]. / Évaluation de l'implantation d'un modèle de concertation local en santé et services sociaux.

OBJECTIVE: To adapt the supply of services to the needs of the community, a local health authority has developed a consultative model in health and social services. This approach, based on shared governance and various health promotion strategies, identifies targets, develops actions, and measures the effects of these actions. This study evaluates the implementation of this consultative model from three dimensions : describe (1) implementation of the model, (2) how user experience was taken into account to prioritize and draw up action plans, (3) favourable and unfavourable implementation conditions. METHODS: A qualitative methodology based on four data sources was used (i.e. individual interviews, focus groups, observations, analysis of reports). Content analysis was conducted on the individual interviews and focus groups. The observations and analysis of reports contributed to enhance the evaluation process. RESULTS: Valorisation of experienced-based knowledge, citizen participation, shared leadership, support from institutions or stakeholders, and the dynamism of discussion tables were favourable to implementation. Time, language, cumbersome procedures, staff instability, the recent reform of the Quebec network and inherent elements of discussion tables were unfavourable conditions. CONCLUSION: The model allows actions adapted to health and social needs of a local population and increases the sense of belonging to a community. Further efforts are required to preserve the relevance, flexibility, and dynamism of this model in a context of restructuring of the Quebec health and social services network.

Group-regularized individual prediction: theory and application to pain.

Multivariate pattern analysis (MVPA) has become an important tool for identifying brain representations of psychological processes and clinical outcomes using fMRI and related methods. Such methods can be used to predict or 'decode' psychological states in individual subjects. Single-subject MVPA approaches, however, are limited by the amount and quality of individual-subject data. In spite of higher spatial resolution, predictive accuracy from single-subject data often does not exceed what can be accomplished using coarser, group-level maps, because single-subject patterns are trained on limited amounts of often-noisy data. Here, we present a method that combines population-level priors, in the form of biomarker patterns developed on prior samples, with single-subject MVPA maps to improve single-subject prediction. Theoretical results and simulations motivate a weighting based on the relative variances of biomarker-based prediction-based on population-level predictive maps from prior groups-and individual-subject, cross-validated prediction. Empirical results predicting pain using brain activity on a trial-by-trial basis (single-trial prediction) across 6 studies (N=180 participants) confirm the theoretical predictions. Regularization based on a population-level biomarker-in this case, the Neurologic Pain Signature (NPS)-improved single-subject prediction accuracy compared with idiographic maps based on the individuals' data alone. The regularization scheme that we propose, which we term group-regularized individual prediction (GRIP), can be applied broadly to within-person MVPA-based prediction. We also show how GRIP can be used to evaluate data quality and provide benchmarks for the appropriateness of population-level maps like the NPS for a given individual or study.