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Klugah-Brown, B.

Publications and source records attributed to Klugah-Brown, B..

8 recordsLinked to original sources

Assessing Microcirculation Impairment in Ischemic Stroke Mice Using Arteriovenous Co-fluctuation Analysis

Accurate assessment of cerebral hemodynamics impairment traditionally relies on arterial metrics, yet often overlooks venous drainage and arteriovenous dynamics, thereby limiting the evaluation of ischemia-induced microvascular dysfunction. To address this limitation, we implemented a signal-averaging framework, combined with co-fluctuation analysis, to extract predominantly arterial and venous hemodynamic signals and construct a dynamic arteriovenous co-fluctuation index that quantifies frame-by-frame coordination between arterial inflow and venous outflow activity. This time-resolved index enables spatial characterization of large-scale cortical arteriovenous coordination beyond conventional static correlation-based analyses. Comparative analyses between healthy controls and acute ischemic stroke mice demonstrated that the arteriovenous co-fluctuation index sensitively detects disruption of vascular coordination, revealing a slower state transition that occurs alongside distinct temporal abnormalities and regional heterogeneity between ischemic core and penumbral regions. These findings underscore the utility of arteriovenous coordination as a sensitive indicator of microcirculatory dysfunction, offering a practical analytical tool for assessing stroke-induced microvascular impairment.

neuroscience↗

Disgust propensity, not disgust sensitivity, shapes the reactivity of a subjective disgust circuit in humans

Disgust constitutes an evolutionary adaptive defensive-avoidance response, yet humans vary markedly in their dispositional tendency to experience disgust (disgust propensity) and in their negative appraisal of such experience (disgust sensitivity). Conceptual frameworks and neuroimaging studies suggest that these traits may differentially modulate neural responses to disgust-eliciting stimuli; however, methodological constraints have left their precise roles unresolved. Our comparably large fMRI study (n = 142) therefore aimed to systematically determine how trait disgust modulates neural responses to carefully selected and validated disgust-specific visual stimuli across varying levels of subjective disgust experience. The whole-brain voxel-wise regression analyses revealed a neural dissociation between the two disgust traits, with disgust propensity, but not disgust sensitivity, modulating disgust-related neural activity in the anterior, middle, and posterior insula, as well as the caudate, putamen, thalamus, hippocampus, and parahippocampal gyrus. Mediation and network-level analyses further supported this dissociation by showing that disgust propensity shapes disgust experience via insula - striatal - hippocampal pathways. Together, these findings provide evidence for a neurofunctional dissociation of disgust propensity and sensitivity and elucidate how trait disgust shapes subjective experiences. They further suggest that disgust propensity and the identified systems may represent promising targets for the regulation of disgust-related pathology.

neuroscience↗

Intelligence and Cognitive Flexibility Selectively Modulate Working Memory Functioning

Working memory is a key component of intelligence, which can be underpinned by task connectome, while cognitive flexibility plays a role in adaptive and executive function that supports working memory processes. However, it remains unknown how intelligence and cognitive flexibility modulate working memory functioning, in terms of behavioural performance and task-related brain hierarchy. Current study investigated the working memory task-related behaviour and brain connectomic gradient in healthy adults together with their intelligence and cognitive flexibility measures. Results showed cognitive flexibility and intelligence were not significantly correlated with each other but with working memory function. Principal component and partial least square analysis revealed that nearly half of variance was explained by their overlap component, which linked with task gradient values of frontoparietal and ventral attention network representing executive, control and cognitive functioning. Individuals with higher intelligence and cognitive flexibility showed less distance between frontoparietal/ventral attention network and unimodal regions in gradient axis during working memory performance. Further analyses demonstrated that task gradient of frontoparietal and ventral attention network was significantly associated with working memory function, and selectively mediated by cognitive flexibility and intelligence, which may suggest partly convergent neural mechanisms for higher order functions that are involved in working memory functioning. In conclusion, current study provides new insight into the relationship among task connectomic gradient, working memory, intelligence, and cognitive flexibility, which helps understand the multi-component model of working memory and underlying task gradient principle.

neuroscience↗

Does Unfairness Evoke Anger or Disgust? A Quantitative Neurofunctional Dissection Based on 25 Years of Neuroimaging

Over the last decades, the traditional Homo economicus model has been increasingly challenged by convergent evidence underscoring the impact of emotions on decision-making. A classic example is the perception of unfairness operationalized in the Ultimatum Game where humans readily sacrifice personal gains to punish those who violate fairness norms. While the emotional mechanism underlying costly punishments has been widely acknowledged, the distinct contributions of moral emotions (anger or disgust) remain debated, partly due to methodological limitations of the conventional experiments. Here, we capitalize on a quantitative neurofunctional dissection approach by combining recent developments in neuroimaging meta-analyses, behavioral-level, network-level, and neurochemical-level decoding and data from 3,266 participants from functional neuroimaging studies to determine the common and distinct neural representations between unfairness and the two moral emotions. Experience of unfairness engaged a widespread bilateral network encompassing insular, cingulate, and frontal regions, with dorsal striatal regions mediating the decision to reject unfair offers. Disgust engaged a defensive-avoidance circuit encompassing amygdalar, occipital, and frontal regions, while anger engaged non-overlapping systems including mid-cingulate, thalamic, and frontal regions. Unfairness and anger or disgust respectively commonly engaged the anterior and mid-insula, while the latter additionally showed common recruitment of ventrolateral prefrontal and orbitofrontal cortices. Multimodal network, behavioral, and serotonergic decoding provided a more granular and convincing dissection of these results. Findings indicate a shared neuroaffective basis underlying the impact of emotions on unfairness-induced punishment behavior and suggest a common brain circuit has been evolutionarily shaped to protect individuals from personal harm and enforce societal norms.

neuroscience↗

The central autonomic system revisited - convergent evidence for a regulatory role of the insular and midcingulate cortex from neuroimaging meta-analyses

The autonomic nervous system regulates dynamic body adaptations to internal and external environment changes. Capitalizing on two different algorithms (Analysis of Brain Coordinates and GingerALE) that differ in empirical assumptions, we scrutinized the meta-analytic convergence of human neuroimaging studies investigating the neural basis of peripheral autonomic signal processing. Among the selected studies, we identified 42 records reporting 44 different experiments and testing 792 healthy individuals. The results of the two different algorithms converge in identifying the bilateral dorsal anterior insula and midcingulate cortex as the critical areas of the central autonomic system (CAN). However, whereas the bilateral dorsal anterior insula appears to be involved in processing autonomic nervous system signals regardless of task type, activity in the midcingulate cortex appears to be primarily engaged in processing autonomic signals during cognitive tasks and task-free conditions. Applying an unbiased approach, we were able to identify a single functionally condition-independent circuit that supports CAN activity. Although partially overlapping with the salience network, this functional circuit includes, in addition to the bilateral insular cortex and midcingulate cortex, the bilateral inferior parietal lobules and small clusters in the bilateral middle frontal gyrus. Our results do not support the hypothesis of divergent pathways for the sympathetic and parasympathetic systems or a robust involvement of the default mode network, particularly during parasympathetic activity. However, these results may be due to the relatively low number of studies investigating the parasympathetic system (12%), making our results more consistent with the central processing network of sympathetic activity. Remarkably, the critical regions of the CAN observed in this meta-analysis are among the most reported co-activated areas in neuroimaging studies and have been repeatedly shown as being dysregulated across different mental and neurological disorders. This suggests that the central dynamic interaction maintaining bodily homeostasis reported in several brain imaging studies may be associated with increased autonomic nervous system engagement and that disruptions in this interplay may underpin unspecific pathological symptoms across mental and neurological disorders.

neuroscience↗

Common and distinct neurofunctional representations of core and social disgust in the brain: An ALE meta-analysis and MACM characterization

Disgust represents a multifaceted defensive-avoidance response. On the behavioral level, the response includes withdrawal and a disgust-specific facial expression. While both serve the avoidance of pathogens, the latter additionally transmits social-communicative information. Given that common and distinct brain representation of the primary defensive-avoidance response (core disgust) and encoding of the social-communicative signal (social disgust) remain debated, we employed neuroimaging meta-analyses to (1) determine brain systems generally engaged in disgust processing, and (2) segregate common and distinct brain systems for core and social disgust. Disgust processing, in general, engaged a bilateral network encompassing the insula, amygdala, occipital and prefrontal regions. Core disgust evoked stronger reactivity in left-lateralized threat detection and defensive response network including amygdala, occipital and frontal regions while social disgust engaged a right-lateralized superior temporal-frontal network engaged in social cognition. Anterior insula, inferior frontal and fusiform regions were commonly engaged during core and social disgust, suggesting a common neural basis. We demonstrate a common and separable neural basis of primary disgust responses and encoding of associated social-communicative signals.

neuroscience↗

Structural-functional connectivity mapping of the insular cortex system: A combined data-driven and meta-analytic topic mapping approach

In this study, we examined structural and functional profiles of the insular cortex and mapped associations with well-described functional networks (FNs) throughout the brain using diffusion tensor imaging (DTI) and resting-state functional connectivity (RSFC) data. We used a data-driven method to independently estimate the structural-functional connectivity of the insular cortex. Data were obtained from the Human Connectome Project comprising 108 adult participants. Overall, we observed moderate to high associations between the structural and functional mapping scores of three different insular subregions: the posterior insula (associated with the sensorimotor network: RSFC, DTI = 50% and 72%, respectively), dorsal anterior insula (associated with ventral attention: RSFC, DTI = 83% and 83%, respectively), and ventral anterior insula (associated with the frontoparietal: RSFC, DTI = 42% and 89%, respectively). Further analyses utilized meta-analytic decoding maps to demonstrate specific cognitive and affective as well as gene expression profiles of the three subregions reflecting the core properties of the insular cortex. In summary, given the central role of the insular in the human brain, our results revealing correspondence between DTI and RSFC mappings provide a complementary approach and insight for clinical researchers to identify dysfunctional brain organization in various neurological disorders associated with insular pathology.

neuroscience↗

Common and separable neural alterations in substance use disorders: evidence from coordinate-based meta-analyses of functional neuroimaging studies in human

Delineating common and separable neural alterations in substance use disorders (SUD) is imperative to understand the neurobiological basis of the addictive process and to inform substance-specific treatment strategies. Given numerous functional MRI (fMRI) studies in different SUDs, meta-analysis could provide an opportunity to determine robust shared and substance-specific alterations. The present study employed a coordinate-based meta-analysis covering fMRI studies in individuals with addictive cocaine, cannabis, alcohol, and nicotine use. The primary meta-analysis demonstrated common alterations in primary dorsal striatal, and frontal circuits engaged in reward/salience processing, habit formation, and executive control across different substances and task-paradigms. Subsequent sub-analyses revealed substance-specific alterations in frontal and limbic regions, with marked frontal and insula-thalamic alterations in alcohol and nicotine use disorders respectively. Finally, examining task-specific alterations across substances revealed pronounced frontal alterations during cognitive processes yet stronger striatal alterations during reward-related processes. Together the findings emphasize the role of dysregulations in striato-frontal circuits and dissociable contributions of these systems in the domains of reward-related and cognitive processes which may contribute to substance-specific behavioral alterations.

neuroscience↗