44 research outputs found

    Towards new recommendations to reduce the burden of alcohol-induced hypertension in the European Union

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    Background: Hazardous and harmful alcohol use and high blood pressure are central risk factors related to premature non-communicable disease (NCD) mortality worldwide. A reduction in the prevalence of both risk factors has been suggested as a route to reach the global NCD targets. This study aims to highlight that screening and interventions for hypertension and hazardous and harmful alcohol use in primary healthcare can contribute substantially to achieving the NCD targets. Methods: A consensus conference based on systematic reviews, meta-analyses, clinical guidelines, experimental studies, and statisticalmodelling which had been presented and discussed in five preparatory meetings, was undertaken. Specifically, we modelled changes in blood pressure distributions and potential lives saved for the five largest European countries if screening and appropriate intervention rates in primary healthcare settings were increased. Recommendations to handle alcohol-induced hypertension in primary healthcare settings were derived at the conference, and their degree of evidence was graded. Results: Screening and appropriate interventions for hazardous alcohol use and use disorders could lower blood pressure levels, but there is a lack in implementing these measures in European primary healthcare. Recommendations included (1) an increase in screening for hypertension (evidence grade: high), (2) an increase in screening and brief advice on hazardous and harmful drinking for people with newly detected hypertension by physicians, nurses, and other healthcare professionals (evidence grade: high), (3) the conduct of clinical management of less severe alcohol use disorders for incident people with hypertension in primary healthcare (evidence grade: moderate), and (4) screening for alcohol use in hypertension that is not well controlled (evidence grade: moderate). The first three measures were estimated to result in a decreased hypertension prevalence and hundreds of saved lives annually in the examined countries. Conclusions: The implementation of the outlined recommendations could contribute to reducing the burden associated with hypertension and hazardous and harmful alcohol use and thus to achievement of the NCD targets. Implementation should be conducted in controlled settings with evaluation, including, but not limited to, economic evaluation.Peer reviewe

    Role of the basal ganglia in cognitive action control : the impact of Parkinson's disease and its treatments

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    Le contrôle cognitif de l’action est un processus permettant de supprimer un comportement inapproprié au profit d’une action dirigée par l’intention. Il est particulièrement important en situation de conflit où l’expression de comportements alternatifs entre en compétition. Ce processus est largement soutenu par des réseaux cortico-sous-corticaux frontaux dont le bon fonctionnement est impacté par la maladie de Parkinson. Nous nous sommes intéressés au rôle de ces différentes structures cérébrales dans le contrôle cognitif de l’action en s’appuyant sur l’impact de la maladie de Parkinson et de ses traitements. Plus précisément, nous avons discuté des aspects dynamiques de sélection et de suppression des réponses impulsives tel que proposé par le modèle d’activation-suppression dans le cas de réponses oculaires. Nous avons donc adapté une tâche expérimentale de conflit classique, la Simon task, utilisant les mouvements oculaires, et validé son utilisation de notre dans le cadre de ce modèle. Les travaux suivant ont porté sur l’impact de divers facteurs sur ce processus. Nous avons montré que le vieillissement normal exacerbe la sélection impulsive des actions qui pourrait être compensée par la mise en place d’une inhibition sélective plus efficace. Ces résultats sont en accord avec de récentes théories proposant le recrutement plus important des structures préfrontales afin de pallier aux déficits cognitifs entrainés par le vieillissement. Nos résultats ont également indiqué que la maladie de Parkinson entraine une augmentation très importante de la sélection impulsive des actions ce que nous attribuons au dysfonctionnement des boucles cortico-sous-corticales causé par la maladie. Finalement, nous nous sommes intéressés à l’impact de la stimulation cérébrale profonde du noyau subthalamique. Nos résultats préliminaires n’ont pas montré d’effet de ce traitement sur les capacités de contrôle cognitif de l’action. Nous discutons l’ensemble de nos résultats à la lumière des travaux majeurs portant sur les structures cérébrales impliquées dans le contrôle cognitif de l’action et proposons plusieurs perspectives de recherches pouvant avoir un impact fondamental ou clinique.Cognitive action control is a process that allows suppressing an inappropriate behavior to the benefit of an intentionally-guided action. It is particularly important in situations of conflict when alternative behaviors compete for their expression. This process relies mostly on cortical-subcortical networks which functioning is impaired by Parkinson’s disease. We were interested in the role of these different brain structures in cognitive action control by focusing on the impact of Parkinson’s diseases and its treatments. More precisely, we addressed the dynamic aspects of impulsive action selection and suppression as proposed by the recent activation-suppression model regarding oculomotor responses. We thus adapted a classical experimental conflict task, the Simon task, using eye movements, and validated its use within the context of the activation-suppression model. Our further work focused on the impact of several factors on cognitive action control. We showed that normal aging enhances impulsive action selection that could be compensated for by the set-up of a more efficient selective inhibition. These results are in accordance with recent theories proposing that age-related cognitive deficits are compensated for by an increased recruitment of prefrontal structures. Our results also revealed that Parkinson’s disease results in a strong increase in impulsive action selection which we attribute to the impairment of the cortical-basal ganglia loops. Finally, we were interested by the impact of deep brain stimulation of the subthalamic nucleus. Our preliminary results revealed no effect of this treatment on cognitive action control. We discuss all of our results according to previous researches on the brain structures involved in cognitive action control and we propose several perspective that can have a fundamental or clinical impact

    RĂ´le des noyaux gris centraux dans le contrĂ´le cognitif de l'action : impact de la maladie de Parkinson et de ses traitements

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    Cognitive action control is a process that allows suppressing an inappropriate behavior to the benefit of an intentionally-guided action. It is particularly important in situations of conflict when alternative behaviors compete for their expression. This process relies mostly on cortical-subcortical networks which functioning is impaired by Parkinson’s disease. We were interested in the role of these different brain structures in cognitive action control by focusing on the impact of Parkinson’s diseases and its treatments. More precisely, we addressed the dynamic aspects of impulsive action selection and suppression as proposed by the recent activation-suppression model regarding oculomotor responses. We thus adapted a classical experimental conflict task, the Simon task, using eye movements, and validated its use within the context of the activation-suppression model. Our further work focused on the impact of several factors on cognitive action control. We showed that normal aging enhances impulsive action selection that could be compensated for by the set-up of a more efficient selective inhibition. These results are in accordance with recent theories proposing that age-related cognitive deficits are compensated for by an increased recruitment of prefrontal structures. Our results also revealed that Parkinson’s disease results in a strong increase in impulsive action selection which we attribute to the impairment of the cortical-basal ganglia loops. Finally, we were interested by the impact of deep brain stimulation of the subthalamic nucleus. Our preliminary results revealed no effect of this treatment on cognitive action control. We discuss all of our results according to previous researches on the brain structures involved in cognitive action control and we propose several perspective that can have a fundamental or clinical impact.Le contrôle cognitif de l’action est un processus permettant de supprimer un comportement inapproprié au profit d’une action dirigée par l’intention. Il est particulièrement important en situation de conflit où l’expression de comportements alternatifs entre en compétition. Ce processus est largement soutenu par des réseaux cortico-sous-corticaux frontaux dont le bon fonctionnement est impacté par la maladie de Parkinson. Nous nous sommes intéressés au rôle de ces différentes structures cérébrales dans le contrôle cognitif de l’action en s’appuyant sur l’impact de la maladie de Parkinson et de ses traitements. Plus précisément, nous avons discuté des aspects dynamiques de sélection et de suppression des réponses impulsives tel que proposé par le modèle d’activation-suppression dans le cas de réponses oculaires. Nous avons donc adapté une tâche expérimentale de conflit classique, la Simon task, utilisant les mouvements oculaires, et validé son utilisation de notre dans le cadre de ce modèle. Les travaux suivant ont porté sur l’impact de divers facteurs sur ce processus. Nous avons montré que le vieillissement normal exacerbe la sélection impulsive des actions qui pourrait être compensée par la mise en place d’une inhibition sélective plus efficace. Ces résultats sont en accord avec de récentes théories proposant le recrutement plus important des structures préfrontales afin de pallier aux déficits cognitifs entrainés par le vieillissement. Nos résultats ont également indiqué que la maladie de Parkinson entraine une augmentation très importante de la sélection impulsive des actions ce que nous attribuons au dysfonctionnement des boucles cortico-sous-corticales causé par la maladie. Finalement, nous nous sommes intéressés à l’impact de la stimulation cérébrale profonde du noyau subthalamique. Nos résultats préliminaires n’ont pas montré d’effet de ce traitement sur les capacités de contrôle cognitif de l’action. Nous discutons l’ensemble de nos résultats à la lumière des travaux majeurs portant sur les structures cérébrales impliquées dans le contrôle cognitif de l’action et proposons plusieurs perspectives de recherches pouvant avoir un impact fondamental ou clinique

    Midfrontal theta phase coordinates behaviorally relevant brain computations during cognitive control

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    International audienceNeural oscillations are thought to provide a cyclic time frame for orchestrating brain computations. Following this assumption, midfrontal theta oscillations have recently been proposed to temporally organize brain computations during conflict processing. Using a multivariate analysis approach, we show that brain-behavior relationships during conflict tasks are modulated according to the phase of ongoing endogenous midfrontal theta oscillations recorded by scalp EEG. We found reproducible results in two independent datasets, using two different conflict tasks brain-behavior relationships (correlation between reaction time and theta power) were theta phase-dependent in a subject-specific manner, and these "behaviorally optimal" theta phases were also associated with fronto-parietal cross-frequency dynamics emerging as theta phase-locked beta power bursts. These effects were present regardless of the strength of conflict. Thus, these results provide empirical evidence that midfrontal theta oscillations are involved in cyclically orchestrating brain computations likely related to response execution during the tasks rather than purely related to conflict processing. More generally, this study supports the hypothesis that phase-based computation is an important mechanism giving rise to cognitive processing

    Synchronization between Keyboard Typing and Neural Oscillations

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    International audienceRhythmic neural activity synchronizes with certain rhythmic behaviors, such as breathing, sniffing, saccades, and speech. The extent to which neural oscillations synchronize with higher-level and more complex behaviors is largely unknown. Here, we investigated electrophysiological synchronization with keyboard typing, which is an omnipresent behavior daily engaged by an uncountably large number of people. Keyboard typing is rhythmic, with frequency characteristics roughly the same as neural oscillatory dynamics associated with cognitive control, notably through midfrontal theta (4-7 Hz) oscillations. We tested the hypothesis that synchronization occurs between typing and midfrontal theta and breaks down when errors are committed. Thirty healthy participants typed words and sentences on a keyboard without visual feedback, while EEG was recorded. Typing rhythmicity was investigated by interkeystroke interval analyses and by a kernel density estimation method. We used a multivariate spatial filtering technique to investigate frequency-specific synchronization between typing and neuronal oscillations. Our results demonstrate theta rhythmicity in typing (around 6.5 Hz) through the two different behavioral analyses. Synchronization between typing and neuronal oscillations occurred at frequencies ranging from 4 to 15 Hz, but to a larger extent for lower frequencies. However, peak synchronization frequency was idiosyncratic across participants, therefore not specific to theta nor to midfrontal regions, and correlated somewhat with peak typing frequency. Errors and trials associated with stronger cognitive control were not associated with changes in synchronization at any frequency. As a whole, this study shows that brain-behavior synchronization does occur during keyboard typing but is not specific to midfrontal theta

    Effect of Variability of Tissue Dielectric Properties on Transcranial Alternating Current Stimulation Induced Electric Field

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    International audienceTranscranial alternating current stimulation modeling is a common procedure to either predict the stimulation clinical effect or to design protocols with optimal parameters. Knowledge of dielectric properties of tissues, especially conductivity, is required to perform such modeling as prior information. However, the low-frequency values of dielectric properties of human tissues are still not well established, and vary between individuals. To address this, analysis of electric field variability due to conductivity variability was assessed recently in the literature. To date, no such analysis has been performed by including permittivity (or tissue capacity) and its own variability. The present study aims to fill this knowledge gap, test the hypothesis, and quantify whether the contribution of permittivity in the analysis of dielectric properties variability impacts the resulting variability of electric field estimation. Furthermore, we provide margins for the electric field and its focality using the extreme values of dielectric properties values reported in the literature. Our results suggest that electric field magnitude, and the component normal to the cortex, are sensitive to conductivity changes, but also to brain tissues permittivity, with an error of neglecting permittivity that can reach almost 40%. Overall, these results contribute to a better understanding of tACS computational modeling

    Effect of Variability of Tissue Dielectric Properties on Transcranial Alternating Current Stimulation Induced Electric Field

    No full text
    International audienceTranscranial alternating current stimulation modeling is a common procedure to either predict the stimulation clinical effect or to design protocols with optimal parameters. Knowledge of dielectric properties of tissues, especially conductivity, is required to perform such modeling as prior information. However, the low-frequency values of dielectric properties of human tissues are still not well established, and vary between individuals. To address this, analysis of electric field variability due to conductivity variability was assessed recently in the literature. To date, no such analysis has been performed by including permittivity (or tissue capacity) and its own variability. The present study aims to fill this knowledge gap, test the hypothesis, and quantify whether the contribution of permittivity in the analysis of dielectric properties variability impacts the resulting variability of electric field estimation. Furthermore, we provide margins for the electric field and its focality using the extreme values of dielectric properties values reported in the literature. Our results suggest that electric field magnitude, and the component normal to the cortex, are sensitive to conductivity changes, but also to brain tissues permittivity, with an error of neglecting permittivity that can reach almost 40%. Overall, these results contribute to a better understanding of tACS computational modeling

    Effects of Parkinson's disease on cognitive action control: Insights on impulsive response tendencies using an oculomotor Simon task

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    International audienceObjectives: Cognitive action control allows suppressing automatic activation and producing a controlled response when conflicts arise. This process is modulated by the basal ganglia and recent studies have shown that it was impaired in Parkinson's disease (PD). This study gives insights regarding the effect of PD on cognitive action and more precisely on impulsive responses. Methods: 40 patients with PD with no cognitive impairment and 40 healthy controls (HC) underwent an oculomotor Simon task in which they were required to make a leftward or rightward eye movement according to the color of a target and to ignore its location. The two dimensions of the stimuli created congruent (color and location activating the same response) and incongruent (color and location activating conflicting responses) trials. Results were analyzed using distributional analysis according to the activation-suppression model. Results: PD patients had a greater congruence effect on both reaction time and accuracy rate demonstrating a greater difficulty to resolve conflicts. Distributional analysis revealed that PD patients made more fast errors than HC. The rate of impulsive errors was further correlated to the Barrat Impulsiveness Scale (BIS) scores. When they responded slower, PD patients were also impaired compared to HC. Conclusions: Our results show that both the automatic and controlled routes involved in the cognitive action control are affected in PD. Furthermore, impulsive response tendencies in PD measured by a conflict task seems related to behavioral impulsivity. Therefore, conflict tasks could be used to further study impulsivity in PD and its ability to detect early troubles should be investigate

    Methods Used to Estimate EEG Source-Space Networks: A Comparative Simulation-Based Study

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    International audienceAlong with the study of the brain activity evoked by external stimuli, an important advance in current neuroscience involves understanding the spontaneous brain activity that occurs during resting conditions. Interestingly, the identification of the connectivity patterns in 'resting-state' has been the subject of a great number of electrophysiology-based studies. In this context, the Electroencephalography (EEG) source connectivity method enables estimating resting-state cortical networks from scalp-EEG recordings. However, there is still no consensus over a unified pipeline adapted in all cases (e.g., type of task, a priori on studied networks) and numerous methodological questions remain unanswered. In order to address this problem, we simulated, using neural mass models, EEG data corresponding to the default mode network (DMN), the most widely studied resting-state network, and tested the effect of different channel densities, two inverse solutions and two functional connectivity measures on the correspondence between the reconstructed networks and the reference networks. Results showed that increasing the number of electrodes enhances the accuracy of the network reconstruction, and that eLORETA/PLV led to better accuracy than other inverse solution/connectivity measure combinations in terms of the correlation between reconstructed and reference connectivity matrices. This work has a wide range of implications in the field of electrophysiology connectomics, and is a step towards a convergence and standardization of approaches in this emerging field. © 2022 IEEE

    Effect of channel density, inverse solutions and connectivity measures on EEG resting-state networks reconstruction: A simulation study

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    International audienceAlong with the study of brain activity evoked by external stimuli, the past two decades witnessed an increased interest in characterizing the spontaneous brain activity occurring during resting conditions. The identification of connectivity patterns in this so-called "resting-state" has been the subject of a great number of electrophysiology-based studies, using the Electro/Magneto-Encephalography (EEG/MEG) source connectivity method. However, no consensus has been reached yet regarding a unified (if possible) analysis pipeline, and several involved parameters and methods require cautious tuning. This is particularly challenging when different analytical choices induce significant discrepancies in results and drawn conclusions, thereby hindering the reproducibility of neuroimaging research. Hence, our objective in this study was to shed light on the effect of analytical variability on outcome consistency by evaluating the implications of parameters involved in the EEG source connectivity analysis on the accuracy of resting-state networks (RSNs) reconstruction. We simulated, using neural mass models, EEG data corresponding to two RSNs, namely the default mode network (DMN) and dorsal attentional network (DAN). We investigated the impact of five channel densities (19, 32, 64, 128, 256), three inverse solutions (weighted minimum norm estimate (wMNE), exact low-resolution brain electromagnetic tomography (eLORETA), and linearly constrained minimum variance (LCMV) beamforming) and four functional connectivity measures (phase-locking value (PLV), phase-lag index (PLI), and amplitude envelope correlation (AEC) with and without source leakage correction), on the correspondence between reconstructed and reference networks. We showed that, with different analytical choices related to the number of electrodes, source reconstruction algorithm, and functional connectivity measure, high variability is present in the results. More specifically, our results show that a higher number of EEG channels significantly increased the accuracy of the reconstructed networks. Additionally, our results showed significant variability in the performance of the tested inverse solutions and connectivity measures. Such methodological variability and absence of analysis standardization represent a critical issue for neuroimaging studies that should be prioritized. We believe that this work could be useful for the field of electrophysiology connectomics, by increasing awareness regarding the challenge of variability in methodological approaches and its implications on reported results
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