Biology subjects

Dobashi, S.

Publications and source records attributed to Dobashi, S..

5 recordsLinked to original sources

bioRxiv2026

Joint Pupillometry and Heart Rate Monitoring Identify Zone-Like High Performance in Esports

Modern digital activities, such as esports, combine intense cognitive demands with limited whole-body movement, weakening calibration between subjective awareness and functional states. Cognitive deterioration during prolonged esports precedes subjective fatigue, suggesting subjective flow likewise fails to reveal efficient cognitive-sensorimotor performance states. Although efficient cognitive-sensorimotor performance may involve central-autonomic coordination reflected in intrapersonal pupil-heart synchrony, the functional role of this coordination remains largely unknown. We hypothesized that, during esports play, central-autonomic coordination contributes to an efficient cognitive-sensorimotor performance state that subjective flow fails to capture. Fourteen young men completed sessions involving watching a fighting game, playing against a computer-controlled opponent, and competing against another person. We assessed pupil diameter, heart rate, subjective flow, subjective workload, and objective in-game performance. Esports competition increased subjective flow without improving objective in-game performance and reduced combat efficiency, demonstrating a subjectively optimal experience need not signal high in-game performance efficiency. Data-driven clustering identified a low-reactivity state combining superior objective in-game performance with lower subjective workload. This state showed selectively sustained pupil-heart synchrony. Reduced workload partly accounted for the association between pupil-heart synchrony and objective in-game performance. Our findings suggest that individuals fail to recognize periods of high in-game performance efficiency, as cognitive deterioration escapes awareness during prolonged esports. This efficiency is associated with pupil-heart synchrony, supporting the hypothesis that central-autonomic coordination contributes to an efficient cognitive-sensorimotor performance state. Pupil-heart synchrony may therefore serve as a mechanism-based biomarker for detecting efficient states beyond awareness, optimizing objective task performance and the timing of recovery in demanding digital environments.

neuroscience↗

bioRxiv2026

Sparkling Water Co-Consumption Enhances Oxytocin-Linked HR Synchrony and Social Connection in Live Sports Spectatorship

Live sport spectatorship can promote social connection, yet scalable, low-burden strategies to strengthen bonding in real-world spectator settings remain limited. We here tested the hypothesis that co-consuming sparkling water during spectating attenuates hunger and fatigue and strengthens enjoyment and perceived unity, potentially via HR synchrony linked to oxytocin dynamics. In an individually randomized field experiment at a collegiate womens basketball home game (sparkling water: n = 21; plain water: n = 19), spectators consumed 200 mL of sparkling water or plain water in synchrony before tip-off and before the end of halftime, with additional ad libitum intake of the assigned beverage permitted thereafter. We assessed acute freshness and hunger, repeated fatigue and enjoyment, interpersonal HR synchrony from the first half to 15-min post-game, perceived unity toward players and fellow spectators, and salivary oxytocin levels. Relative to plain water, sparkling water increased freshness and reduced hunger after intake, attenuated post-game fatigue, and enhanced enjoyment and perceived unity. HR synchrony was preserved in association with attenuated post-game fatigue after the game, and sustained synchrony was associated with higher perceived unity. Oxytocin decreased more in the sparkling-water group, and this decrease was associated with preserved HR synchrony as well as with changes in unity toward fellow fans. These findings support our hypothesis and suggest that co-consuming sparkling water serves as an alcohol-free, low-burden ritual to enhance social connection during and after live sport events. Highlights- Sparkling water increased freshness and reduced hunger after intake in spectators. - Sparkling water attenuated the post-game increase in subjective fatigue. - Sparkling water increased enjoyment and perceived unity. - Post-game HR synchrony was preserved in association with lower fatigue and higher unity. - Oxytocin decreased more with sparkling water and tracked HR synchrony and fan unity. - Co-consuming sparkling water is a low-burden, alcohol-free ritual for social connection.

neuroscience↗

bioRxiv2025

Live sports spectating promotes oxytocin dynamics and heart rate synchrony in casual fans

Oxytocin has been proposed as a pharmacological target for social dysfunction. However, clinical trials of exogenous oxytocin have yielded modest and inconsistent benefits, highlighting the need for naturalistic, non-pharmacological approaches that recruit endogenous oxytocin. This prospective observational field study examined whether live sports spectating in a modest collegiate setting engages endogenous oxytocin and heart rate synchrony, and how these processes relate to social bonding. Sixty casual spectators at two university basketball games provided salivary samples for oxytocin and cortisol and completed psychological questionnaires before the game, at halftime, and after the game, while heart rate was continuously recorded. Oxytocin dynamics were baseline dependent: individuals with low pre-game oxytocin showed clear increases during spectating, whereas those with high pre-game oxytocin maintained elevated concentrations; across both groups, cortisol decreased and the oxytocin-to-cortisol ratio increased, indicating a shift toward an oxytocin-dominant, low-stress hormonal profile. Live spectating also enhanced heart rate synchrony between spectators, and higher oxytocin levels and stronger synchrony were associated with greater enjoyment, stronger unity with players and fellow fans, higher flow, and stronger intention to revisit. Mediation analyses indicated that perceived unity mediated links between physiological responses and experiential outcomes. These findings identify coordinated oxytocin dynamics and physiological synchrony as candidate mechanisms through which live sports spectating can foster social connection and positive psychological states in everyday, low-stakes settings. Live sports events may represent a simple, scalable non-pharmacological approach to engaging oxytocin-related systems and interpersonal synchrony to promote social connection in everyday life.

neuroscience↗

bioRxiv2023

A single bout of vigorous exercise decreases subsequent non-exercise physical activity and body temperature

PurposeExercise benefits the body and mind, but its weight loss effect is less than generally expected. Although this phenomenon is likely primarily due to a decrease in non-exercise physical activity (NEPA) resulting in a decrease in non-exercise activity thermogenesis, the underlying mechanisms and effects of exercise intensity remain unknown. Here we show that acute vigorous exercise decreases subsequent NEPA and body temperature (BT) in association with body weight gain. MethodsAdult male C57BL/6J mice were categorized into three groups: sedentary, moderate exercise, and vigorous exercise, with exercise groups undergoing a 30 min treadmill session. Using an intraperitoneally implanted activity monitor, NEPA and BT were monitored for two days before and three days after exercise. The daily synchrony between NEPA and BT was evaluated using a cross-correlation function. Plasma corticosterone was also detected 6 and 24 h after exercise. ResultsNotably, Only the vigorous exercise group exhibited a decline in both NEPA and BT, resulting in body weight gain the following day, despite no observed changes in food intake. Furthermore, vigorous exercise induces a distinct delay in the daily dynamics of NEPA compared to BT. A positive correlation was observed between plasma corticosterone levels and changes in NEPA levels before and after exercise across all exercise groups. ConclusionsOur findings provide evidence for vigorous exercise-specific reduction in subsequent NEPA, BT, and their synchrony linked to weight gain, likely due to the disturbed circadian rhythm of corticosterone. This ultimately redefines the significance of exercise intensity in beneficial effects beyond the energy expenditure of the exercise itself.

animal behavior and cognition↗

bioRxiv2023

Lactate Dynamics in Skin Interstitial Fluid Predicts Lactate Threshold in Exercising Rats

Regular exercise promotes various anti-ageing adaptations in skin tissue. Although the underlying mechanisms of that might associate to the acute exercise-induced lactate signaling in the skin, it remains uncertain the profile of skin interstitial fluid (ISF) lactate dynamics during and following acute exercise. Here, we investigated whether the skin ISF lactate level increases in association with blood lactate during acute incremental exercise using a single microneedle perfusion system. The rats were acclimated to treadmill running exercise and underwent external jugular vein cannulation. Following comprehensive recovery, a 1 mm single microneedle was implanted into the back skin. Skin ISF lactate progressively increased in tandem with blood lactate during the incremental exercise but did not decrease to baseline levels until 30 minutes following the exercise unlike blood. Moreover, lactate threshold (LT), is a crucial marker of athletic aerobic performance during acute exercise, extrapolated from skin ISF showed significant alignment with blood LT. Our findings reveal that the skin ISF lactate increases associated with blood lactate and the long-lasting elevation state following acute exercise. Moreover, lactate dynamics in skin ISF can predict LT. These findings would be a milestone for elucidating regular exercise-induced physiological adaptations in the skin and evaluating athletic performance. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=90 SRC="FIGDIR/small/563585v3_ufig1.gif" ALT="Figure 1"> View larger version (32K): org.highwire.dtl.DTLVardef@14520a7org.highwire.dtl.DTLVardef@162f538org.highwire.dtl.DTLVardef@1d13979org.highwire.dtl.DTLVardef@1145abe_HPS_FORMAT_FIGEXP M_FIG C_FIG Lactate levels in rat skin interstitial fluid (ISF) increased in association with blood lactate during acute incremental exercise, but the increase in skin ISF lactate lasted 30 min following acute exercise. Lactate threshold (LT), a crucial marker of aerobic athletic performance, can be predicted from skin fluid dynamics during acute exercise. These findings would be a milestone for elucidating regular exercise-induced physiological adaptations in the skin and evaluating athletic performance.

physiology↗