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Focal brain injuries, such as stroke, cause local structural damage as well as alteration of neuronal activity in distant brain regions. Experimental evidence suggests that one of these changes is the appearance of sleep-like slow waves in the otherwise awake individual. This pattern is prominent in areas surrounding the damaged region and can extend to connected brain regions in a way consistent with the individual's specific long-range connectivity patterns. In this paper we present a generative whole-brain model based on (f)MRI data that, in combination with the disconnection mask associated with a given patient, explains the effects of the sleep-like slow waves originated in the vicinity of the lesion area on the distant brain activity. Our model reveals new aspects of their interaction, being able to reproduce functional connectivity patterns of stroke patients and offering a detailed, causal understanding of how stroke-related effects, in particular slow waves, spread throughout the brain. The presented findings demonstrate that the model effectively captures the links between stroke occurrences, sleep-like slow waves, and their subsequent spread across the human brain., Competing Interests: Declaration of competing interest Marcello Massimini is co-founder of Intrinsic Powers, a spin-off of the University of Milan., (Copyright © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Computational whole-brain models describe the resting activity of each brain region based on a local model, inter-regional functional interactions, and a structural connectome that specifies the strength of inter-regional connections. Strokes damage the healthy structural connectome that forms the backbone of these models and produce large alterations in inter-regional functional interactions. These interactions are typically measured by correlating the time series of the activity between two brain regions in a process, called resting functional connectivity. We show that adding information about the structural disconnections produced by a patient's lesion to a whole-brain model previously trained on structural and functional data from a large cohort of healthy subjects enables the prediction of the resting functional connectivity of the patient and fits the model directly to the patient's data (Pearson correlation = 0.37; mean square error = 0.005). Furthermore, the model dynamics reproduce functional connectivity-based measures that are typically abnormal in stroke patients and measures that specifically isolate these abnormalities. Therefore, although whole-brain models typically involve a large number of free parameters, the results show that, even after fixing those parameters, the model reproduces results from a population very different than that on which the model was trained. In addition to validating the model, these results show that the model mechanistically captures the relationships between the anatomical structure and the functional activity of the human brain., Competing Interests: The authors do not have any potential conflict of interest to report., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Guarantors of Brain.)

The brain is organized hierarchically to process sensory signals. But, how do functional connections within and across areas contribute to this hierarchical order? We addressed this problem in the thalamocortical network, while monkeys detected vibrotactile stimulus. During this task, we quantified neural variability and directed functional connectivity in simultaneously recorded neurons sharing the cutaneous receptive field within and across VPL and areas 3b and 1. Before stimulus onset, VPL and area 3b exhibited similar fast dynamics while area 1 showed slower timescales. During the stimulus presence, inter-trial neural variability increased along the network VPL-3b-1 while VPL established two main feedforward pathways with areas 3b and 1 to process the stimulus. This lower variability of VPL and area 3b was found to regulate feedforward thalamocortical pathways. Instead, intra-cortical interactions were only anticipated by higher intrinsic timescales in area 1. Overall, our results provide evidence of hierarchical functional roles along the thalamocortical network., Competing Interests: All authors have no relevant financial or non-financial interests to disclose., (© 2024 The Authors.)

Objectives: The aim of this study was to examine the mediating effect of the psychosocial work environment on the association between precarious employment (PE) and increased risk of common mental disorders (CMD), substance use disorders and suicide attempts., Methods: This longitudinal register-study was based on the working population of Sweden, aged 25-60 years in 2005 (N=2 552 589). Mediation analyses based on a decomposition of counterfactual effects were used to estimate the indirect effect of psychosocial risk factors (PRF) (mediators, measured in 2005) on the association between PE (exposure, measured in 2005) and the first diagnosis of CMD, substance use disorders, and suicide attempts occurring over 2006-2017., Results: The decomposition of effects showed that the indirect effect of the PRF is practically null for the three outcomes considered, among both sexes. PE increased the odds of being diagnosed with CMD, substance use disorders, and suicide attempts, among both men and women. After adjusting for PE, low job control increased the odds of all three outcomes among both sexes, while high job demands decreased the odds of CMD among women. High job strain increased the odds of CMD and suicide attempts among men, while passive job increased the odds of all three outcomes among women., Conclusion: The results of this study did not provide evidence for the hypothesis that psychosocial risks could be the pathways linking precarious employment with workers` mental health. Future studies in different social contexts and labour markets are needed.

Brain signal irreversibility has been shown to be a promising approach to study neural dynamics. Nevertheless, the relation with cortical hierarchy and the influence of different electrophysiological features is not completely understood. In this study, we recorded local field potentials (LFPs) during spontaneous behavior, including awake and sleep periods, using custom micro-electrocorticographic (μECoG) arrays implanted in ferrets. In contrast to humans, ferrets remain less time in each state across the sleep-wake cycle. We deployed a diverse set of metrics in order to measure the levels of complexity of the different behavioral states. In particular, brain irreversibility, which is a signature of non-equilibrium dynamics, captured by the arrow of time of the signal, revealed the hierarchical organization of the ferret's cortex. We found different signatures of irreversibility and functional hierarchy of large-scale dynamics in three different brain states (active awake, quiet awake, and deep sleep), showing a lower level of irreversibility in the deep sleep stage, compared to the other. Irreversibility also allowed us to disentangle the influence of different cortical areas and frequency bands in this process, showing a predominance of the parietal cortex and the theta band. Furthermore, when inspecting the embedded dynamic through a Hidden Markov Model, the deep sleep stage was revealed to have a lower switching rate and lower entropy production. These results suggest functional hierarchies in organization that can be revealed through thermodynamic features and information theory metrics., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Idesis et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Large-scale brain networks reveal structural connections as well as functional synchronization between distinct regions of the brain. The latter, referred to as functional connectivity (FC), can be derived from neuroimaging techniques such as functional magnetic resonance imaging (fMRI). FC studies have shown that brain networks are severely disrupted by stroke. However, since FC data are usually large and high-dimensional, extracting clinically useful information from this vast amount of data is still a great challenge, and our understanding of the functional consequences of stroke remains limited. Here, we propose a dimensionality reduction approach to simplify the analysis of this complex neural data. By using autoencoders, we find a low-dimensional representation encoding the fMRI data which preserves the typical FC anomalies known to be present in stroke patients. By employing the latent representations emerging from the autoencoders, we enhanced patients' diagnostics and severity classification. Furthermore, we showed how low-dimensional representation increased the accuracy of recovery prediction., (© 2023. Springer Nature Limited.)

Background: Evidence on health inequalities has been growing over the past few decades, yet the capacity to produce research on health inequalities varies between countries worldwide and needs to be strengthened. More in-depth understanding of the sociohistorical, political and institutional processes that enable this type of research and related research capacity to be generated in different contexts is needed. A recent bibliometric analysis of the health inequalities research field found inequalities in the global production of this type of research. It also found the United Kingdom to be the second-highest global contributor to this research field after the United States. This study aims to understand why and how the United Kingdom, as an example of a "high producer" of health inequalities research, has been able to generate so much health inequalities research over the past five decades, and which main mechanisms might have been involved in generating this specific research capacity over time., Methods: We conducted a realist explanatory case study, which included 12 semi-structured interviews, to test six theoretical mechanisms that we proposed might have been involved in this process. Data from the interviews and grey and scientific literature were triangulated to inform our findings., Results: We found evidence to suggest that at least four of our proposed mechanisms have been activated by certain conditions and have contributed to the health inequalities research production process in the United Kingdom over the past 50 years. Limited evidence suggests that two new mechanisms might have potentially also been at play., Conclusions: Valuable learning can be established from this case study, which explores the United Kingdom's experience in developing a strong national health inequalities research tradition, and the potential mechanisms involved in this process. More research is needed to explore additional facilitating and inhibiting mechanisms and other factors involved in this process in this context, as well as in other settings where less health inequalities research has been produced. This type of in-depth knowledge could be used to guide the development of new health inequalities research capacity-strengthening strategies and support the development of novel approaches and solutions aiming to tackle health inequalities., (© 2023. The Author(s).)

The mechanisms controlling dynamical patterns in spontaneous brain activity are poorly understood. Here, we provide evidence that cortical dynamics in the ultra-slow frequency range (<0.01-0.1 Hz) requires intact cortical-subcortical communication. Using functional magnetic resonance imaging (fMRI) at rest, we identify Dynamic Functional States (DFSs), transient but recurrent clusters of cortical and subcortical regions synchronizing at ultra-slow frequencies. We observe that shifts in cortical clusters are temporally coincident with shifts in subcortical clusters, with cortical regions flexibly synchronizing with either limbic regions (hippocampus/amygdala), or subcortical nuclei (thalamus/basal ganglia). Focal lesions induced by stroke, especially those damaging white matter connections between basal ganglia/thalamus and cortex, provoke anomalies in the fraction times, dwell times, and transitions between DFSs, causing a bias toward abnormal network integration. Dynamical anomalies observed 2 weeks after stroke recover in time and contribute to explaining neurological impairment and long-term outcome., (© 2022. The Author(s).)

Most neuroimaging studies of post-stroke recovery rely on analyses derived from standard node-centric functional connectivity to map the distributed effects in stroke patients. Here, given the importance of nonlocal and diffuse damage, we use an edge-centric approach to functional connectivity in order to provide an alternative description of the effects of this disorder. These techniques allow for the rendering of metrics such as normalized entropy, which describes the diversity of edge communities at each node. Moreover, the approach enables the identification of high amplitude co-fluctuations in fMRI time series. We found that normalized entropy is associated with stroke lesion severity and continually increases across the time of patients' recovery. Furthermore, high amplitude co-fluctuations not only relate to the lesion severity but are also associated with patients' level of recovery. The current study is the first edge-centric application for a clinical population in a longitudinal dataset and demonstrates how a different perspective for functional data analysis can further characterize topographic modulations of brain dynamics., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Understanding the effect of focal lesions (stroke) on brain structure-function traditionally relies on behavioral analyses and correlation with neuroimaging data. Here we use structural disconnection maps from individual lesions to derive a causal mechanistic generative whole-brain model able to explain both functional connectivity alterations and behavioral deficits induced by stroke. As compared to other models that use only the local lesion information, the similarity to the empirical fMRI connectivity increases when the widespread structural disconnection information is considered. The presented model classifies behavioral impairment severity with higher accuracy than other types of information (e.g.: functional connectivity). We assessed topological measures that characterize the functional effects of damage. With the obtained results, we were able to understand how network dynamics change emerge, in a nontrivial way, after a stroke injury of the underlying complex brain system. This type of modeling, including structural disconnection information, helps to deepen our understanding of the underlying mechanisms of stroke lesions., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

The measurement of respondents' attitudes is key in social science research and many adjacent research fields. A common method to measure this information is to use Likert-type questions that consist of a statement that is evaluated with a rating scale. As shown by previous research, the scale design of Likert-type questions can have a profound impact on respondents' answer behavior. In this study, we therefore investigate the measurement properties of scales that systematically vary with respect to polarity (i.e., unipolar and bipolar) and labeling (i.e., completely and end). We conducted a survey experiment in a probability-based online panel (N = 4851) and used questions on income (in)equality that were adopted from the European Social Survey (ESS). The results reveal considerable differences between the scales under investigation. They show that end labeled unipolar and bipolar scales accomplish the criteria of equidistance best. Completely labeled bipolar scales, in contrast, only show a poor performance in terms of equidistance. Completely labeled unipolar scales are somewhere in between. Overall, our findings suggest that researchers should be careful when using survey data measured with (slightly) different scales because the results might not be comparable., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background: Physical activity is associated with mental health benefits. This systematic literature review summarises extant evidence regarding this association, and explores differences observed between populations over sixty-five years and those younger than sixty-five., Methods: We reviewed articles and grey literature reporting at least one measure of physical activity and at least one mental disorder, in people of all ages., Results: From the 2263 abstracts screened, we extracted twenty-seven articles and synthesized the evidence regarding the association between physical (in)activity and one or more mental health outcome measures. We confirmed that physical activity is beneficial for mental health. However, the evidence was mostly based on self-reported physical activity and mental health measures. Only one study compared younger and elder populations, finding that increasing the level of physical activity improved mental health for middle aged and elder women (no association was observed for younger women). Studies including only the elderly found a restricted mental health improvement due to physical activity., Conclusions: We found inverse associations between levels of physical activity and mental health problems. However, more evidence regarding the effect of ageing when measuring associations between physical activity and mental health is needed. By doing so, prescription of physical activity could be more accurately targeted.

Motor decision-making is often described as a sequential process, beginning with the assessment of available options and leading to the execution of a selected movement. While this view is likely to be accurate for decisions requiring significant deliberation, it would seem unfit for choices between movements in dynamic environments. In this study, we examined whether and how non-selected motor options may be considered post-movement onset. We hypothesized that a change in reward at any point in time implies a dynamic reassessment of options, even after an initial decision has been made. To test this, we performed a decision-making task in which human participants were instructed to execute a reaching movement from an origin to a rectangular target to attain a reward. Reward depended on arrival precision and on the specific distribution of reward presented along the target. On a third of trials, we changed the initial reward distribution post-movement onset. Our results indicated that participants frequently change their initially selected movements when a change is associated with an increase in reward. This process occurs quicker than overall, average reaction times. Finally, changes in movement are not only dependent on reward but also on the current state of the motor apparatus.

Background: Despite increasing evidence on health inequalities over the past decades, further efforts to strengthen capacities to produce research on this topic are still urgently needed to inform effective interventions aiming to address these inequalities. To strengthen these research capacities, an initial comprehensive understanding of the health inequalities research production process is vital. However, most existing research and models are focused on understanding the relationship between health inequalities research and policy, with less focus on the health inequalities research production process itself. Existing conceptual frameworks provide valuable, yet limited, advancements on this topic; for example, they lack the capacity to comprehensively explain the health (and more specifically the health inequalities) research production process at the local level, including the potential pathways, components and determinants as well as the dynamics that might be involved. This therefore reduces their ability to be empirically tested and to provide practical guidance on how to strengthen the health inequalities research process and research capacities in different settings. Several scholars have also highlighted the need for further understanding and guidance in this area to inform effective action., Methods: Through a critical review, we developed a novel conceptual model that integrates the social determinants of health and political economy perspectives to provide a comprehensive understanding of how health inequalities research and the related research capacities are likely to be produced (or inhibited) at local level., Results: Our model represents a global hypothesis on the fundamental processes involved, and can serve as a heuristic tool to guide local level assessments of the determinants, dynamics and relations that might be relevant to better understand the health inequalities research production process and the related research capacities., Conclusions: This type of knowledge can assist researchers and decision-makers to identify any information gaps or barriers to be addressed, and establish new entry points to effectively strengthen these research capacities. This can lead to the production of a stronger evidence base, both locally and globally, which can be used to inform strategic efforts aimed at achieving health equity.

Temporal orienting leads to well-documented behavioural benefits for sensory events occurring at the anticipated moment. However, the consequences of temporal orienting in cross-modal contexts are still unclear. On the one hand, some studies using audio-tactile paradigms suggest that attentional orienting in time and modality are a closely coupled system, in which temporal orienting dominates modality orienting, similar to what happens in cross-modal spatial attention. On the other hand, recent findings using a visuo-tactile paradigm suggest that attentional orienting in time can unfold independently in each modality, leading to cross-modal decoupling. In the present study, we investigated if cross-modal decoupling in time can be extrapolated to audio-tactile contexts. If so, decoupling might represent a general property of cross-modal attention in time. To this end, we used a speeded discrimination task in which we manipulated the probability of target presentation in time and modality. In each trial, a manipulation of time-based expectancy was used to guide participants' attention to task-relevant events, either tactile or auditory, at different points in time. In two experiments, we found that participants generally showed enhanced behavioural performance at the most likely onset time of each modality and no evidence for coupling. This pattern supports the hypothesis that cross-modal decoupling could be a general phenomenon in temporal orienting.

Archaeology provides few examples of large-scale fisheries at the frontier between catching and farming of fish. We analysed the spatial organization of earthen embankments to infer the functioning of a landscape-level pre-Columbian Amazonian fishery that was based on capture of out-migrating fish after reproduction in seasonal floodplains. Long earthen weirs cross floodplains. We showed that weirs bear successive V-shaped features (termed 'Vs' for the sake of brevity) pointing downstream for outflowing water and that ponds are associated with Vs, the V often forming the pond's downstream wall. How Vs channelled fish into ponds cannot be explained simply by hydraulics, because Vs surprisingly lack fishways, where, in other weirs, traps capture fish borne by current flowing through these gaps. We suggest that when water was still high enough to flow over the weir, out-migrating bottom-hugging fish followed current downstream into Vs. Finding deeper, slower-moving water, they remained. Receding water further concentrated fish in ponds. The pond served as the trap, and this function shaped pond design. Weir-fishing and pond-fishing are both practiced in African floodplains today. In combining the two, this pre-Columbian system appears unique in the world.

Background: The growing demand for labour flexibility has resulted in decreasing employment stability that could be associated with poor mental health status. Few studies have analysed the whole of the work force in considering this association since research on flexible forms of employment traditionally analyses employed and unemployed people separately. The gender division of work, and family characteristics related to employment situation, could modify its association with mental wellbeing. The objective of the study was to examine the relationship between a continuum of employment stability and mental health taking into account gender and partner/marital status., Methods: We selected 6859 men and 5106 women currently salaried or unemployed from the 2006 Spanish National Health Survey. Employment stability was measured through a continuum from the highest stability among employed to lowest probability of finding a stable job among the long-term unemployed. Mental health was measured with the 12-item version of the General Health Questionnaire. Logistic regression models were fitted for each combination of partner/marital status and gender., Results: In all groups except among married women employment stability was related to poor mental health and a gradient between a continuum of employment stability and mental health status was found. For example, compared with permanent civil servants, married men with temporary contract showed an aOR = 1.58 (95%CI = 1.06-2.35), those working without a contract aOR = 2.15 (95%CI = 1.01-4.57) and aOR = 3.73 (95%CI = 2.43-5.74) and aOR = 5.35 (95%CI = 2.71-10.56) among unemployed of up to two years and more than two years, respectively. Among married and cohabiting people, the associations were stronger among men. Poor mental health status was related to poor employment stability among cohabiting women but not among married ones. The strongest association was observed among separated or divorced people., Conclusions: There is a rise in poor mental health as the distance from stable employment grows. This result differs according to the interaction with gender and partner/marital status. In Spain this relationship seems to follow a pattern related to the gender division of work in married people but not in other partner/marital situations. Family and socioeconomic context can contribute to explain previous mixed results. Recommendations for research and for action are given.

In everyday life, we often must coordinate information across spatial locations and different senses for action. It is well known, for example, that reactions are faster when an imperative stimulus and its required response are congruent than when they are not, even if stimulus location itself is completely irrelevant for the task (the so-called Simon effect). However, because these effects have been frequently investigated in single-modality scenarios, the consequences of spatial congruence when more than one sensory modality is at play are less well known. Interestingly, at a behavioral level, the visual Simon effect vanishes in mixed (visual and tactile) modality scenarios, suggesting that irrelevant spatial information ceases to exert influence on vision. To shed some light on this surprising result, here we address the expression of irrelevant spatial information in EEG markers typical of the visual Simon effect (P300, theta power modulation, LRP) in mixed-modality contexts. Our results show no evidence for the visual-spatial information to affect performance at behavioral and neurophysiological levels. The absence of evidence of the neural markers of visual S-R conflict in the mixed-modality scenario implies that some aspects of spatial representations that are strongly expressed in single-modality scenarios might be bypassed., (© 2018 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)

Quite a lot of research is available on the relationships between survey response scales' characteristics and the quality of responses. However, it is often difficult to extract practical rules for questionnaire design from the wide and often mixed amount of empirical evidence. The aim of this study is to provide first a classification of the characteristics of response scales, mentioned in the literature, that should be considered when developing a scale, and second a summary of the main conclusions extracted from the literature regarding the impact these characteristics have on data quality. Thus, this paper provides an updated and detailed classification of the design decisions that matter in questionnaire development, and a summary of what is said in the literature about their impact on data quality. It distinguishes between characteristics that have been demonstrated to have an impact, characteristics for which the impact has not been found, and characteristics for which research is still needed to make a conclusion.

Background: The recent economic crisis has been a major shock not only to the economic sector, but also to the rest of society. Our main objective in this paper is to show the impact of the economic crisis on convergence, i.e. the reduction or equalising of disparities, among the EU-27 countries in terms of health. The aim is to observe whether the economic crisis (from 2008 onwards) has in fact had an effect on health inequalities within the EU., Methods: We estimate convergence by specifying a dynamic panel model with random-effects (time, regions and countries). We are particularly interested in σ-convergence. As dependent variables, we use life expectancy, total mortality and (cause-specific) mortality in the regions of the EU-27 countries over the period 1995-2011., Results: The results of the analysis show that, in terms of health, there has been a catching-up process among the EU regions. However, we find no reduction, on average, in dispersion levels as the σ-convergence shows. The main finding of this paper has been the sharp increase in disparities in 2010 for all health outcomes (albeit less abrupt for cancer mortality)., Conclusion: This increase in disparities in 2010 coincides with the austerity measures implemented in the EU countries. Our main conclusion is that these austerity measures have had an impact on socioeconomic inequalities.