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Clairis, N.

Publications and source records attributed to Clairis, N..

4 recordsLinked to original sources

Hippocampal-somatomotor coactivation and perceived benefit following Mindfulness-Based Cognitive Therapy for Life in healthcare students: An exploratory randomized study

Mindfulness-based interventions are known to enhance emotion regulation and stress management, yet their neural mechanisms remain incompletely understood. Effective coping strategies for emotion regulation and stress management would be particularly beneficial for healthcare students, frequently exposed to highly stressful situations. Based on prior work implicating hippocampal-somatomotor dynamics in emotion regulation, we tested whether Mindfulness-Based Cognitive Therapy for Life (MBCT-L) modulates hippocampal micro-coactivation patterns (CAPs) in healthcare students. In a randomized controlled study including 161 healthcare students, 57 participants (39 females; mean age: 23+/-5 years old) completed resting-state fMRI before and after the 8-weeks intervention and were allocated to MBCT-L (N = 24) or a no-intervention control (N = 33) condition. Hippocampus-seeded CAPs analysis identified six recurrent patterns, including a somatomotor network. MBCT-L improved self-reported mindfulness, but no significant Group*Time interaction for hippocampus-somatomotor coactivation or resting physiological measures was found. In the MBCT-L group, higher hippocampus-somatomotor co-activity was associated with higher perceived importance of the intervention, perceived long-lasting benefits, and post-intervention mindfulness scores. This study suggests that the capacity to up-regulate hippocampus-somatomotor coactivation may index part of the individual benefit derived from mindfulness, supporting its role as a tool for emotion regulation and stress management.

neuroscience↗

A neurometabolic mechanism for effort-based decision-making in the dmPFC/dACC

Motivation levels vary across individuals, yet the underlying mechanisms driving these differences remain elusive. The dorsomedial prefrontal cortex/dorsal anterior cingulate cortex (dmPFC/dACC) and the anterior insula (aIns) play crucial roles in effort-based decision-making. Here, we investigate the influence of lactate, a key metabolite involved in energy metabolism and signaling, on decisions involving both physical and mental effort, as well as its effects on neural activation. Using proton magnetic resonance spectroscopy and functional MRI in 63 participants, we find that higher lactate levels in the dmPFC/dACC are associated with reduced motivation for physical effort, a relationship mediated by neural activity within this region. Additionally, plasma and dmPFC/dACC lactate levels correlate, suggesting a systemic influence on brain metabolism. Supported by path analysis, our results highlight lactates role as a modulator of dmPFC/dACC activity, hinting at a neurometabolic mechanism that integrates both peripheral and central metabolic states with brain function in effort-based decision-making.

neuroscience↗

Predicting individual variations in mental effort-based decision-making using machine learning: Neurometabolic signature in the dorsomedial prefrontal cortex/dorsal anterior cingulate cortex

Motivation drives individuals to overcome costs to achieve desired outcomes, such as rewards or avoidance of punishment, with significant variability across individuals. The dorsomedial prefrontal cortex/dorsal anterior cingulate cortex (dmPFC/dACC) and anterior insula are key brain regions implicated in effort-based decision-making. Here, we utilized proton magnetic resonance spectroscopy (1H-MRS) at 7 Tesla on 69 healthy participants in these brain regions to uncover the neurometabolic factors that influence these differences. We designed and applied an effort-based decision-making task requiring mental and physical effort to probe motivated behavior, complemented by computational modeling to extract key behavioral parameters. Gradient boosting machine learning was applied to explore the predictive role of specific metabolites in motivated behavior. Our results reveal that a model established on dmPFC/dACC metabolites explains decisions to exert high mental effort and sensitivity to mental effort. In particular, glutamate, aspartate, and lactate in dmPFC/dACC, three metabolites linked through the tricarboxylic acid cycle and glycolysis, were identified as key discriminative metabolites in the dmPFC/dACC, predictive of mental effort choices, underpinning energy supply and cognitive processes. Anterior insula metabolites did not significantly relate to effort-related decisions. Notably, glutamine and lactate levels between the periphery (plasma) and the dmPFC/dACC were correlated, suggesting a metabolic link between peripheral and central biomarkers of effort. Our findings provide novel insights into the neurometabolic underpinnings of motivated behavior and propose novel biomarkers for mental effort-based decision-making. Importantly, our study highlights the relevance of multivariable approaches in elucidating complex cognitive functions.

neuroscience↗

Value, confidence and deliberation in preference tasks: a triple dissociation in the medial prefrontal cortex

Deciding about courses of action involves minimizing costs and maximizing benefits. Decision neuroscience studies have implicated both the ventral and dorsal medial prefrontal cortex (vmPFC and dmPFC) in signaling goal value and action cost, but the precise functional role of these regions is still a matter of debate. Here, we suggest a more general functional partition that applies not only to decisions but also to judgments about goal value (expected reward) and action cost (expected effort). In this conceptual framework, cognitive representations related to options (reward value and effort cost) are dissociated from metacognitive representations (confidence and deliberation) related to solving the task (providing a judgment or making a choice). Thus, we used an original approach with the goal of identifying consistencies across several preference tasks, from likeability ratings to binary decisions involving both attribute integration and option comparison. FMRI results confirmed the vmPFC as a generic valuation system, its activity increasing with reward value and decreasing with effort cost. In contrast, more dorsal regions were not concerned with the valuation of options but with metacognitive variables, confidence level being reflected in mPFC activity and deliberation time in dmPFC activity. Thus, there was a dissociation between the effort attached to choice options (represented in the vmPFC) and the effort invested in deliberation (represented in the dmPFC), the latter being expressed in pupil dilation. More generally, assessing commonalities across preference tasks might help reaching a unified view of the neural mechanisms underlying the cost/benefit tradeoffs that drive human behavior.

neuroscience↗