ECSS Paris 2023: OP-SH02
Background: Enhanced attentional control is linked to mentally tough behaviours and overall superior sporting performance. One potential explanation for this connection is that attentional control (AC) may help regulate psychophysiological responses to stress, such as gaze behaviour and heart rate, leading to increased focus on task demands and reduced distraction from irrelevant stimuli. Research suggests that individuals sensitive to punishment are more adept at identifying and reacting to threats early. This may help to lower anxiety and free up attentional resources, allowing for superior AC. This study aimed to investigate the impact of punishment (PS) and reward sensitivities (RS) on cognitive performance and psychophysiological responses to stress. Methods: 83 participants completed three AC tasks targeting shifting, inhibition, and updating. Each task involved coins with varying monetary values under two conditions: gain/no gain (clicking earns money, failure to click results in no gain) and loss/non-loss (failure to click results in a loss, clicking prevents it). Tasks included a practice block, low-stress block (no carryover of earned money), and a high-stress block (where real monetary rewards were based on gains and losses). In the first task (shifting), participants were given £20 credit in the loss condition, providing them with money to lose. Eye tracking and heart rate variability were recorded throughout. Hypothesis: Individuals with high PS focus on avoiding loss, and their early threat detection may reduce anxiety and improve AC during high-stress tasks. In contrast, those with high RS may be more distracted by gains, leaving fewer resources to manage task demands. Results: Preliminary data shows a significant increase in self-report anxiety across conditions (t(43) = -3.69, p = .001). Shifting-task data shows individuals high in PS clicked more coins (β = 2.83, p = .01) than those high in RS (β = 1.70, p = .18), with PS individuals accounting for 24% of the variability in the gain, high-stress condition. Both PS and RS fixated more on the gain condition, though PS individuals demonstrated a greater increase in eye fixation duration on gain coins (β = 1262.45, p = .01), compared to their RS counterparts (β = 978.02, p = .07), with PS predicting 28% of the variability from gain to loss in high stress. Conclusion: Individuals high in PS excel at task-switching, clicking more coins, fixating longer, and showing less distraction by losses. This may result from stress-induced recruitment of attentional resources, which blunts their stress response to loss and leads them to use strategies (such as utilising the £20 credit in the loss condition to maximize gains and prevent greater overall loss). In contrast, individuals high in RS struggled with task demands, clicking fewer coins and fixating less, for shorter periods. This suggests that the presence of rewards may impair task-switching performance, in RS individuals.
Read CV Louisa CoddECSS Paris 2023: OP-SH02
Introduction: Mental fatigue impairs performance and safety. This research aims to uncover the underlying causes of mental fatigue by identifying factors that intensify and accelerate its onset. We developed computer-based protocols manipulating (a) cognitive-control demands and (b) real-time task difficulty adjustments designed to promote sustained engagement with the fatiguing activity. Methods: In a within-subject single-task study (n = 36) and a between-subject multi-task study (n = 72), we manipulated task parameters from three executive function domains (inhibition, switching, updating) across conditions of (a) lower vs higher cognitive-control demands without difficulty adjustments and (b) high cognitive control with vs without difficulty adjustments, where speed increased following correct responses and decreased otherwise. Subjective, behavioural, and physiological data were analysed for changes in cognitive load, task engagement, and fatigue. Statistical significance was evaluated using ANOVA planned contrasts and reported as percentage changes. Results: The within-subject study showed that higher (vs lower) cognitive control increased perceived workload by 16.25% while reducing boredom by 23.80% and sleepiness by 6.40%. It also slowed responses by 9.75%, impaired accuracy by 2.65%, and decreased blink rate by 11.50%. Difficulty adjustments (vs none) heightened workload by 34.33% and led to 7.08% less accurate but 32.58% faster responses, with a further 15.89% reduction in blink rate. The between-subject study extended these findings to mental fatigue. Higher (vs lower) cognitive control did not consistently elevate perceived workload but led to 11.01% lower accuracy and 58.98% slower response times. Difficulty adjustments (vs none) increased workload by 37.22% across all executive function domains and impaired accuracy by 23.85% while speeding up responses by 20.24%. Mental fatigue was 60.87% larger at the end than the beginning of the study on average across all conditions but emerged 28.69% faster under higher cognitive-control demands with (vs without) difficulty speed adjustments. A 15.22% reduction in parasympathetic activity and 78.98% more blink flurries were observed immediately after (vs before) completing the high cognitive-control condition with difficulty adjustments, possibly reflecting compensatory responses to elevated cognitive workload. Conclusion: These findings reveal how prolonged exertion of cognitive control and task difficulty adjustments can intensify cognitive load and fatigue. While the former can create additional cognitive load, the latter promotes task engagement and accelerates fatigue onset. Beyond identifying contributors to mental fatigue, this research introduces an innovative, time-efficient approach that addresses limitations of previous one-size-fits-all fatiguing protocols, promising to reduce opportunity for disengagement and therefore variability in individual responses in mental fatigue.
Read CV Thipkanlaya JaiaueECSS Paris 2023: OP-SH02
Introduction It is well established that mental fatigue (MF) limits various forms of physical performance. Brain Endurance Training (BET) is a MF countermeasure that combines demanding cognitive tasks that systematically induce elevated levels of MF through engaging higher order executive functions alongside regular physical training. BET has been proven to be effective in improving running, cycling, rhythmic handgrip, and bodyweight calisthenic exercise performance. However, its application to strength and resistance training is less well understood. This study explored the effects of BET on sub-maximal strength training and potential underlying mechanisms that may explain training-related changes in performance. Method Forty-two resistance-trained student athletes were randomly assigned to either high cognitive load (high BET group) or low cognitive load (low BET group) conditions and completed 12 training sessions over 4 weeks. In pre- and post-testing, they completed sets to failure at 60% of one repetition maximum for bench press (compound) and preacher curl (isolation) exercise when “fresh” and when mentally and physically “fatigued”. Performance (number of exercise repetitions to failure), perceived exertion, and mental fatigue were assessed. Linear displacement transducers recorded lifting kinematics (including velocity) while surface electromyography (sEMG) transducers recorded muscle activation patterns. Results In pre-testing, exercise performance did not differ between groups. Performance improved in post-testing for both groups as a result of training. In post-testing, the high BET group performed more bench press repetitions than the low BET group both in a ‘fresh’ and ‘fatigued’ state. No group differences were observed for preacher curl repetitions. Ratings of perceived exertion (reported after five repetitions) were lower for the high BET group than the low BET group suggesting that increased cognitive demands during training recalibrated the effort-exercise relationship. The high BET group also reported less mental fatigue despite completing more repetitions before failure. Discussion The findings show that BET enhances resistance exercise performance and confirm its applicability to strength and conditioning. They also reveal that exercise performance enhancement requires sufficient cognitive load during training to recalibrate the relationship between perceived effort and actual effort. Finally, differences in performance enhancement between the compound and isolated exercises suggest that BET may help improve neuromuscular control.
Read CV Hannah MortimerECSS Paris 2023: OP-SH02