Biology subjects

Park, S. Q.

Publications and source records attributed to Park, S. Q..

4 recordsLinked to original sources

bioRxiv2026

Slow breathing impacts inter-organ dynamics modulating brain function and risk behavior

Successful decision-making requires that external information be interpreted in the context of the bodys state. Within the framework of body-brain interaction, deliberately modifying ones autonomic state can shape how we evaluate the world, ultimately influencing choices. Yet, it remains unclear whether and how intentional autonomic regulation affects human decision-making. In this study, we tested instructed prolonged exhalation, a slow-breathing technique designed to boost parasympathetic activity during risky decision-making. Participants followed distinct breathing protocols while making risky choices, with neural and physiological activity measured using fMRI and multi-channel monitoring. Prolonged exhalation increased risky choices by enhancing reward sensitivity and elevating cardiac parasympathetic activity. Importantly, individuals with greater parasympathetic upregulation also showed stronger reward-related responses in the ventromedial prefrontal cortex and precuneus. Our work reveals a transformative role for breathing-based interventions, demonstrating that breathing-based autonomic regulation can shape value-based decision-making through neuro-cardiac pathways. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=107 SRC="FIGDIR/small/698695v1_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@190293corg.highwire.dtl.DTLVardef@1835c63org.highwire.dtl.DTLVardef@1267ff3org.highwire.dtl.DTLVardef@9a583e_HPS_FORMAT_FIGEXP M_FIG C_FIG HIGHLIGHTSO_LIProlonged exhalation increases risky decisions by increasing the reward sensitivity C_LIO_LIProlonged exhalation enhances cardiac parasympathetic activity without dampening sympathetic activities C_LIO_LIGreater cardiac parasympathetic activity under prolonged exhalation amplifies neural reward sensitivity in the ventromedial prefrontal cortex and precuneus C_LI

neuroscience↗

bioRxiv2026

Neuro-metabolic pathways of high-protein meal reducing food craving

Across species, high-protein foods have been shown to reduce appetite throughout the day. Although higher protein intake alters multiple metabolic responses, the exact neuro-metabolic mechanisms underlying food craving remain unclear. Here, we investigated whether a protein-rich diet modulates plasma tyrosine dynamics, the precursor of dopamine, thereby altering dopaminergic brain activity and reducing food craving in humans. In this within-subject, cross-over study, 30 healthy participants (age, Mean=23.63, SD=3.23 years) were provided with either a high- or low-protein/carbohydrate breakfast. Three and a half hours after breakfast, participants viewed high-or low caloric food images while undergoing magnetic resonance imaging (MRI), and their subjective food craving was assessed using the validated Food Craving Questionnaire- State version. Through the experimental procedure, plasma tyrosine levels were continuously monitored. Our results show that the high-protein/carbohydrate breakfast significantly enhanced plasma tyrosine levels, which were negatively associated with subjective food craving several hours after meal intake. Importantly, we observed significantly stronger midbrain activity following the high-protein/carbohydrate breakfast, which was associated with greater reduction in subjective food craving. Furthermore, we analyzed brain gradients that characterize spatial patterns of large-scale neural activity, allowing us to examine the entire process underlying dietary choices at the whole-brain level. Compared with the low-protein/carbohydrate breakfast, the high-protein/carbohydrate breakfast reduced whole-brain functional reorganization, indicating lower neural sensitivity to high- versus low-caloric food stimuli. Notably, the degree of this high-protein/carbohydrate induced brain-state shift was related to the reduction in food craving. Together, these results provide strong evidence that high-protein/carbohydrate meals modulate dopaminergic mechanisms and large-scale whole-brain neural reorganization, contributing to reduced food craving throughout the day in humans.

neuroscience↗

bioRxiv2022

Neural correlates of changing food choices while bypassing values

Current theories suggest that altering choices requires value modification. To investigate this, normal-weight participants food choices and values were tested before and after an approach-avoidance training (AAT), while neural activity was recorded during the choice task using functional magnetic resonance imaging (fMRI). During AAT, participants consistently approached low-while avoiding high-calorie food cues. AAT facilitated low-calorie food choices, leaving food values unchanged. Instead, we observed a shift in indifference points, indicating the decreased contribution of food values in food choices. Training-induced choice shifts were associated with increased activity in the posterior cingulate cortex (PCC). In contrast, the medial PFC activity was not changed. Additionally, PCC grey matter density predicted individual differences in training-induced functional changes, suggesting anatomic predispositions to training impact. Our findings demonstrate neural mechanisms underlying choice modulation independent of valuation-related processes, with substantial theoretical significance for decision-making frameworks and translational implications for health-related decisions resilient to value shifts.

neuroscience↗

bioRxiv2020

Eating to dare - Nutrition impacts human risk decision and related brain function

Macronutrient composition modulates plasma amino acids that are precursors of neurotransmitters and can impact brain function and decisions. Neurotransmitter serotonin has been shown to regulate not only food intake, but also economic decisions. We investigated whether an acute nutrition-manipulation inducing plasma tryptophan fluctuation affects brain function, thereby affecting risky decisions. Breakfasts differing in carbohydrate/protein ratios were offered to test changes in risky decision making while metabolic and neural dynamics were tracked. We identified that a high-carbohydrate/protein meal increased plasma tryptophan which mapped to individual risk propensity changes. Moreover, the meal-driven fluctuation in tryptophan and risk propensity changes were modulated by individual difference in body fat mass. Using fMRI, we further identified activation in the parietal lobule during risk-processing, of which activities 1) were correlated with the risk propensity changes in decision making, 2) were sensitive to the tryptophan fluctuation, and 3) were modulated by individuals body fat mass. Furthermore, the activity in the parietal lobule positively mediated the tryptophan-fluctuation to risk-propensity-changes relationship. Our results provide evidence for a personalized nutrition-driven modulation on human risky decisions and its metabolic and neural mechanisms.

neuroscience↗