The impact of cognitive work demands on subsequent physical activity behavior.

After cognitively demanding work, individuals tend to be less physically active. However, the psychological mechanisms underlying this effect have not been thoroughly tested. The aim of this article was to experimentally investigate the impact of cognitive work demands on subsequent physical activity behavior. Across two preregistered experiments, participants were exposed to high or low levels of cognitive work demands, operationalized as workload in Experiment 1 and as working-memory load in Experiment 2. In a subsequent choice task, participants made binary consequential choices between leisure nonphysical activities (e.g., drawing) and effortful physical activities (e.g., cycling). Choice alternatives were matched on attractiveness rankings. Additionally, physical endurance performance was measured using a standardized cycling protocol in Experiment 1. In contrast to the hypotheses, after performing work with high cognitive demands, participants were not more likely to choose nonphysical over physical activities nor did they perform significantly worse on the physical endurance task. Exploratory analyses suggest that preexisting preferences for either physical or nonphysical activities explained physical activity behavior above and beyond exposure to cognitively demanding work. These experiments question the impact of cognitively demanding work on subsequent cognitive fatigue and physical activity behavior. Implications for theory, practice, and future directions are discussed. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Sedentary work and participation in leisure-time physical activity.

OBJECTIVE: Demanding psychosocial work characteristics, such as high job demands, can have a detrimental impact on leisure-time physical activity (LTPA), with adverse consequences for employee health and well-being. However, the mechanisms and moderators of this crossover effect are still largely unknown. We therefore aimed to identify and test potential mediating and moderating factors from within and outside the work environment. Based on the previous research, we expected job demands to be negatively related to LTPA through fatigue. In addition, we expected that job control and worktime control would attenuate the relationship between job demands and fatigue. Furthermore, we hypothesized that autonomous exercise motivation and spontaneous action planning would attenuate the relationship between fatigue and LTPA. In addition to these cross-sectional hypotheses, we expected the same effects to predict a change in LTPA in the following year. METHODS: To investigate these assumptions, a preregistered longitudinal survey study was conducted among a large sample of Dutch employees in sedentary jobs. Participants reported on the constructs of interest in 2017 and 2018 (N = 1189 and 665 respectively) and the resulting data were analyzed using path analyses. RESULTS: Our cross-sectional analyses confirm a weak indirect, negative association between job demands and LTPA, via fatigue. However, this finding was not observed in our longitudinal analyses and none of the other hypotheses were confirmed. CONCLUSION: This study shows that, among employees with relatively healthy psychosocial work characteristics (i.e., high job control), the evidence for an impact of these work characteristics on participation in LTPA is limited.

The effect of opportunity costs on mental fatigue in labor/leisure trade-offs.

Most people experience the feeling of mental fatigue on a daily basis. Previous research shows that mental fatigue impacts information processing and decision making. However, the proximal causes of mental fatigue are not yet well understood. In this research, we test the opportunity cost model of mental fatigue, which proposes that people become more fatigued when the next-best alternative to the current task is higher in value. In 4 preregistered experiments (N = 430), participants repeatedly reported their current level of fatigue and chose to perform a paid labor task versus an unpaid leisure task. In Study 1, all participants were offered the same labor/leisure choice. In Studies 2 and 3, we manipulated the opportunity costs of a labor task by varying the value of an alternative leisure task. In Study 4, we manipulated the opportunity costs of a labor task by varying the value of that labor task. In all studies, we found that people were more likely to choose for leisure as they became more fatigued. In Studies 2 through 4, we did not find that the manipulated leisure value influenced the amount of fatigue participants experienced nor the likelihood to choose for leisure. However, in exploratory analyses, in all studies, we found that participants who reported to value the leisure task more got more fatigued during labor and less fatigued during leisure. Collectively, these results provide cautious support for the opportunity cost model, but they also show that cost-benefit analyses relating to labor and leisure tasks are fleeting. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The Impact of Cognitive and Physical Effort Exertion on Physical Effort Decisions: A Pilot Experiment.

Research suggests that cognitive fatigue has a negative impact on physical activity participation. However, the mechanisms underlying this effect are yet unclear. Using an effort-based decision-making paradigm, we examined whether individuals weigh physical effort-costs more strongly when they are cognitively or physically fatigued. Twenty university students visited the lab on three occasions. On each visit, participants underwent a manipulation that was designed to either induce cognitive fatigue (i.e., 2-back task), physical fatigue (i.e., handgrip exercise), or served as a control condition (i.e., documentary watching). After the manipulations, participants performed an effort-based decision-making task in which they decided for 125 offers whether they accepted the offer to exert the required level of physical effort to obtain rewards that varied in value. The probability to accept offers declined with increasing effort requirements whereas the general probability to accept offers was not reduced by any of the experimental conditions. As expected, the decline in accepted offers with increasing effort requirements was stronger after prolonged exertion of physical effort compared to the control condition. Unexpectedly, this effect was not found after exerting cognitive effort, and exploratory analyses revealed that the impact of physical effort exertion on physical effort-based decisions was stronger than that of cognitive effort exertion. These findings suggest that people weight future physical effort-costs more strongly after exerting physical effort, whereas we could not find any evidence for this after exerting cognitive effort. We discuss multiple explanations for this discrepancy, and outline possibilities for future research.

Dim light, sleep tight, and wake up bright - Sleep optimization in athletes by means of light regulation.

Despite an elevated recovery need, research indicates that athletes often exhibit relatively poor sleep. Timing and consolidation of sleep is driven by the circadian system, which requires periodic light-dark exposure for stable entrainment to the 24-hour day, but is often disturbed due to underexposure to light in the morning (e.g. low-level indoor lighting) and overexposure to light in the evening (e.g. environmental and screen-light). This study examined whether combining fixed sleep schedules with light regulation leads to more consolidated sleep. Morning light exposure was increased using light-emitting goggles, whereas evening light exposure was reduced using amber-lens glasses. Using a within-subject crossover design, twenty-six athletes (14 female, 12 male) were randomly assigned to start the intervention with the light-regulation-week or the no light-regulation-week. Sleep was monitored by means of sleep diaries and actigraphy. Due to low protocol adherence regarding the fixed sleep-wake schedules, two datasets were constructed; one including athletes who kept a strict sleep-wake schedule (N = 8), and one that also included athletes with a more lenient sleep-wake schedule (N = 25). In case of a lenient sleep-wake schedule, light regulation improved self-reported sleep onset latency (Δ SOL = 8 min). This effect was stronger (Δ SOL = 17 min) and complemented by enhanced subjective sleep quality in case of a strict sleep-wake schedule. None of the actigraphy-based estimates differed significantly between conditions. To conclude, light regulation may be considered a potentially effective strategy to improve subjective sleep, but less obtrusive methods should be explored to increase protocol compliance.

Reward-driven distraction: A meta-analysis.

People have a strong tendency to attend to reward cues, even if these cues are irrelevant to their current goal or their current task. When reward cues are goal-irrelevant, their presence may impair cognitive performance. In this meta-analysis, we quantitatively examined the rapidly growing literature on the impact of reward-related distractors on cognitive performance. We included 91 studies (N = 2,362) that used different cognitive paradigms (e.g., visual search, conflict processing) and reward-related stimuli (e.g., money, attractive food). Overall, results showed that reward-related distractors impaired cognitive performance across different tasks and stimuli, with a small effect size (standardized mean change = .347). Between-study heterogeneity was large, suggesting that researchers can plausibly expect to sometimes find reversed effects (i.e., reward-related distractors boosting performance). We further showed that the average reward-driven distraction effect was robust across different reward-learning mechanisms, contexts, and methodological choices, and that this effect existed regardless of explicit task instructions to ignore distractors. In sum, the findings of this meta-analysis support the notion that cognitive processes can be thwarted by reward cues. We discuss these findings against the background of distraction-related phenomena as they are studied in clinical, educational, and work psychology. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Motivation counteracts fatigue-induced performance decrements in soccer passing performance.

Recent theories suggest that negative effects of fatigue on performance are determined by perception of effort and motivation rather than being directly caused by reaching physiological limits. In the current experiment, the influence of motivation on fatigue-induced decrements in soccer performance was experimentally investigated. Sixty amateur soccer players performed a validated soccer-passing test before and after a fatigue protocol. Results showed that players' motivation and performance decreased after the fatigue protocol for players in the control group. In contrast, players in the motivation group (i.e., with motivation experimentally induced after the fatigue protocol) were able to uphold their motivation and increase their performance. These results indicate that motivation plays a crucial role in performance under fatigue, as fatigue-induced decrements in soccer passing performance can be counteracted by high levels of motivation. Future research may explore the limits of this counteracting effect and extend findings to other relevant performance aspects.

Restricting short-wavelength light in the evening to improve sleep in recreational athletes - A pilot study.

Sleep is crucial for recovery and skill acquisition in athletes. Paradoxically, athletes often encounter difficulties initiating and maintaining sleep, while having sufficient sleep opportunity. Blue (short-wavelength) light as emitted by electronic screens is considered a potential sleep thief, as it suppresses habitual melatonin secretion. The current study sought to investigate whether blocking short-wavelength light in the evening can improve sleep onset latency and potentially other sleep parameters among recreational athletes. The study had a within-subject crossover design. Fifteen recreational athletes, aged between 18 and 32 years (12 females, 3 males), were randomly assigned to start the intervention period with either the light restriction condition (LR; amber-lens glasses), or the no-light restriction condition (nLR; transparent glasses). Sleep hygiene practices, actigraphy and diary-based sleep estimates were monitored during four consecutive nights within each condition. Sleep hygiene practices did not significantly differ between conditions. Results indicate that blocking short-wavelength light in the evening, as compared to habitual light exposure, significantly shortened subjective sleep onset latency (Δ = 7 min), improved sleep quality (Δ = 0.6; scale 1-10), and increased alertness the following morning. Actigraphy-based sleep estimates showed no significant differences between conditions. Blocking short-wavelength light in the evening by means of amber-lens glasses is a cost-efficient and promising means to improve subjective sleep estimates among recreational athletes in their habitual home environment. The relatively small effects of the current study may be strengthened by additionally increasing morning- and daytime light exposure and, potentially, by reducing the alerting effects of media use before bedtime.

Effects of Natural Between-Days Variation in Sleep on Elite Athletes' Psychomotor Vigilance and Sport-Specific Measures of Performance.

Performance capacity in athletes depends on the ability to recover from past exercise. While evidence suggests that athletic performance decreases following (partial) sleep deprivation and increases following sleep extension, it is unclear to which extent natural variation in sleep impacts performance. Sleep quantity and, for the first time, sleep stages were assessed among 98 elite athletes on three non-consecutive nights within a 7-day monitoring period, along with performance tests that were taken on standardized times each following morning. Performance assessment included psychomotor performance (10-minute psychomotor vigilance task) and sport-specific tests of fine (e.g., accuracy) and gross motor skills (e.g., endurance, power). Mixed-effects models were employed to assess the effect of sleep quantity (total sleep time (TST), sleep onset latency (SOL), wake after sleep onset, sleep efficiency) and sleep stage duration (light, deep, REM) on performance. Average TST was 7:30 ± 1:05 hours, with a mean variation of 57 minutes across days. Longer TSTs were associated with faster reaction times (p = 0.04). Analyses indicated small and inconsistent effects of sleep quantity (TST, SOL) and sleep staging (light sleep) on gross motor performance, and no effects on fine motor skill performance. Results indicate that natural variation in sleep quantity impacts psychomotor vigilance to a greater extent than athletic performance. Small or absent effects can be a consequence of the rather small variation in non-manipulated sleep. It is suggested that one night of compromised sleep may not be immediately problematic, but that more extreme sleep loss or accumulated sleep debt may have more severe consequences.

Reward-associated distractors can harm cognitive performance.

When people carry out cognitive tasks, they sometimes suffer from distractions, that is, drops in performance that occur close in time to task-irrelevant stimuli. In this research, we examine how the pursuit of rewards contributes to distractions. In two experiments, participants performed a math task (in which they could earn monetary rewards vs. not) while they were exposed to task-irrelevant stimuli (that were previously associated with monetary rewards vs. not). In Experiment 1, irrelevant cues that were previously associated with rewards (vs. not) impaired performance. In Experiment 2, this effect was only replicated when these reward-associated distractors appeared relatively early during task performance. While the results were thus somewhat mixed, they generally support the idea that reward associations can augment the negative effect of distractors on performance.

Trajectories of well-being during an exercise randomized controlled trial: The role of exposure and exercise experiences.

We examined how process factors were related to the development of various indicators of well-being during the course of an exercise randomized controlled trial aimed at reducing fatigue among university students. We investigated (a) whether actual exposure to the exercise sessions was related to differences in students' trajectories of well-being, (b) the minimally required exposure to exercise needed before well-being started to differ between the intervention and control condition, and (c) whether exercise experiences (enjoyment and detachment) were related to differences in well-being trajectories. University students with high levels of fatigue were randomly allocated to a 6-week exercise intervention (n = 50) or wait list (n = 49). All participants were measured before, 5 times during, and at the end of the intervention period. Multilevel analyses showed that exercisers with high exposure showed an increase in self-efficacy whereas those with low exposure did not. Effects of exercise on well-being became visible after 2 to 4 weeks during the intervention period and (partly) depended on the extent of psychological detachment. We recommend that both outcomes and process factors throughout the intervention period should be measured in order to better understand "when" and "under what conditions" an exercise intervention works.

Train hard, sleep well? Perceived training load, sleep quantity and sleep stage distribution in elite level athletes.

OBJECTIVES: Sleep is essential for recovery and performance in elite athletes. While it is generally assumed that exercise benefits sleep, high training load may jeopardize sleep and hence limit adequate recovery. To examine this, the current study assessed objective sleep quantity and sleep stage distributions in elite athletes and calculated their association with perceived training load. DESIGN: Mixed-methods. METHODS: Perceived training load, actigraphy and one-channel EEG recordings were collected among 98 elite athletes during 7 consecutive days of regular training. RESULTS: Actigraphy revealed total sleep durations of 7:50±1:08h, sleep onset latencies of 13±15min, wake after sleep onset of 33±17min and sleep efficiencies of 88±5%. Distribution of sleep stages indicated 51±9% light sleep, 21±8% deep sleep, and 27±7% REM sleep. On average, perceived training load was 5.40±2.50 (scale 1-10), showing large daily variability. Mixed-effects models revealed no alteration in sleep quantity or sleep stage distributions as a function of day-to-day variation in preceding training load (all p's>.05). CONCLUSIONS: Results indicate healthy sleep durations, but elevated wake after sleep onset, suggesting a potential need for sleep optimization. Large proportions of deep sleep potentially reflect an elevated recovery need. With sleep quantity and sleep stage distributions remaining irresponsive to variations in perceived training load, it is questionable whether athletes' current sleep provides sufficient recovery after strenuous exercise.

Self-reported sleep quantity, quality and sleep hygiene in elite athletes.

Sleep is essential for recovery and performance in elite athletes. While actigraphy-based studies revealed suboptimal sleep in athletes, information on their subjective experience of sleep is scarce. Relatively unexplored is also the extent to which athletes' sleep is adversely affected by environmental conditions and daytime behaviours, that is sleep hygiene. This study aimed to provide insight in sleep quantity, quality and its putative association with sleep hygiene. Participants were 98 elite (youth) athletes competing at the highest (inter-)national level. Sleep quantity, quality and sleep hygiene were assessed once covering a 1-month period by using established (sub)clinical questionnaires, and repeatedly during 7 consecutive days. Sleep quality was generally healthy, although 41% of all athletes could be classified as 'poor sleeper', and 12% were identified as having a sleep disorder. Daily self-monitoring revealed sleep durations of 8:11 ± 0:45 h, but elevated wake after sleep onset of 13 ± 19 min. Sleep quality, feeling refreshed, and morning vigor were moderate at best. Regarding sleep hygiene, general measures revealed irregular sleep-wake patterns, psychological strain and activating pre-sleep behaviours. At the daily level, blue-light exposure and late-evening consumption of heavy meals were frequently reported. General sleep hygiene revealed significant associations with sleep quality (0.45 < r > 0.50; P < 0.001). Results indicate that there is ample room for optimization, specifically in onset latency and in wake after sleep onset. Subtle improvements in sleep seem possible, and optimizing sleep hygiene, such as regular sleep-wake patterns and reducing psychological strain, may facilitate this sleep upgrading process.

Systematic review of the association between physical activity and burnout.

OBJECTIVE: Burnout constitutes a health risk, and interventions are needed to reduce it. The aim of this study was to synthesize evidence regarding the relationship between physical activity and burnout by conducting a systematic review of longitudinal and intervention studies. METHODS: A literature search resulted in the identification of a final set of ten studies: four longitudinal and six intervention studies. In separate analyses for each category, evidence was synthesized by extracting the study characteristics and assessing the methodological quality of each study. The strength of evidence was calculated with the standardized index of convergence (SIC). RESULTS: In longitudinal studies, we found moderately strong evidence (SIC (4) = -1) for a negative relationship between physical activity and the key component of burnout, i.e., exhaustion. We found strong evidence (SIC (6) = -0.86) for the effect of physical activity on reducing exhaustion in intervention studies. As only one study could be classified as a high quality study, these results of previous studies need to be interpreted with some caution. CONCLUSIONS: This systematic review suggests that physical activity constitutes an effective medium for the reduction of burnout. Although consistent evidence was found, there is a lack of high quality longitudinal and intervention studies considering the influence of physical activity on burnout. Therefore, future research should be conducted with the aim to produce high quality studies, to develop a full picture of physical activity as a strategy to reduce burnout.

The effect on sleep of being on-call: an experimental field study.

The aim of this study was to: (i) gain more insight into the relationship between being on-call and sleep and (ii) investigate the role of stress in this relationship. Data were collected by means of an experimental field study with a within-subject design (two conditions, random order). Ninety-six students participated during two consecutive nights: a reference night and a simulated on-call night without an actual call. Participants were told they could be called at any time during the on-call night. In the case of a call, participants had to perform online tasks for approximately 30 min. Self-reported sleep quality and the extent to which participants experienced stress during the on-call period were assessed by means of short questionnaires. Actigraphy was used to obtain objective sleep measures. Results for actigraphy data revealed no significant within-person differences between conditions. However, participants reported longer sleep onset latencies, more awakenings and more wake after sleep onset during the on-call night than during the reference night. They also reported more sleep problems and a lower overall sleep quality, and felt less recuperated after the on-call night. Perceived stress moderated the relationship between being on-call, on one hand, and the number of awakenings, wake after sleep onset, sleep problems and overall sleep quality, on the other hand. Results show that, even in the absence of an actual call, sleep during on-call nights is of lower quality and has less restorative value - especially when being on-call is experienced as stressful.

Exercise to reduce work-related fatigue among employees: a randomized controlled trial.

Objectives The present study evaluated the efficacy of an exercise intervention to reduce work-related fatigue (emotional exhaustion, overall fatigue, and need for recovery). The effects of exercise on self-efficacy, sleep, work ability, cognitive functioning and aerobic fitness (secondary outcomes) were also investigated. Methods Employees with high levels of work-related fatigue were randomly assigned to either a 6-week exercise intervention (EI; N=49) or a wait-list control group (WLC; N=47). All participants were measured pre- (T0) and post-intervention (T1). EI participants were also measured 6 (T2) and 12 weeks (T3) after the end of the intervention. Analyses were based on intention-to-treat (ITT) and per-protocol (PP). PP analyses only included EI participants (N=31) who completed the intervention and WLC participants (N= 35) who did not increase their exercise level during the wait period. Results Analyses of covariance (ANCOVA) revealed that, at T1, the EI group reported lower emotional exhaustion and overall fatigue than the WLC group, however, only according to PP analyses. Both according to ITT and PP analyses, EI participants showed higher sleep quality, work ability, and self-reported cognitive functioning at T1 compared to WLC participants. Intervention effects were maintained at T2 and T3. Conclusions The exercise intervention had enduring effects on work-related fatigue and broader indicators of employee well-being. This study demonstrates that, in case of work-related fatigue, exercise does constitute a powerful medicine for those who comply with the treatment.

Effects of new ways of working on work hours and work location, health and job-related outcomes.

New ways of working (NWW) is a type of work organization that is characterized by temporal and spatial flexibility, often combined with extensive use of information and communication technologies (ICT) and performance-based management. In a three-wave intervention study, we examined the effects of NWW on both the organization of work (changes in control over time and place of work; working hours and work location; and other key job characteristics), and on employees' outcomes (work-nonwork balance; health and well-being; and job-related outcomes). We applied a quasi-experimental design within a large Dutch financial company (N = 2,912). We studied an intervention group (n = 2,391) and made comparisons with a reference group (n = 521). There were three study waves: (i) one/two months before, and (ii) 4 months and (iii) 10 months after implementation of NWW. Repeated measures analyses of covariance (involving 361 participants from the intervention group and 80 participants from the reference group) showed a large and significant shift from hours worked at the office to hours worked at home after implementation of NWW. Accordingly, commuting time was reduced. Employees remained working on week days and during day time. Psychosocial work-characteristics, work-nonwork balance, stress, fatigue, and job-related outcomes remained favourable and largely unaffected, but the health score in the intervention group decreased (medium effect). These findings suggest that the implementation of NWW does not necessarily lead to changes in psychosocial work characteristics, well-being or job-related outcomes.

Exercise as an Intervention to Reduce Study-Related Fatigue among University Students: A Two-Arm Parallel Randomized Controlled Trial.

BACKGROUND: Many university students experience high levels of study-related fatigue. This high prevalence, and the negative impact of fatigue on health and academic performance, call for prevention and reduction of these symptoms. The primary aim of the current study was to investigate to what extent an exercise intervention is effective in reducing three indicators of study-related fatigue (emotional exhaustion, overall fatigue, and need for recovery). Effects of exercise on secondary outcomes (sleep quality, self-efficacy, physical fitness, and cognitive functioning) were also investigated. METHODS: Participants were students with high levels of study-related fatigue, currently not exercising or receiving other psychological or pharmacological treatments, and with no medical cause of fatigue. They were randomly assigned to either a six-week exercise intervention (low-intensity running three times a week, n = 49) or wait list (no intervention, n = 48). All participants were measured before the intervention (T0), and immediately after the intervention (T1). Exercisers were also investigated 4 weeks (T2) and 12 weeks (T3) after the intervention. RESULTS: Participants in the exercise condition showed a larger decrease in two of the three indicators of study-related fatigue (i.e., overall fatigue and need for recovery) as compared to controls. Additionally, sleep quality and some indicators of cognitive functioning improved more among exercisers than among controls. No effects were found for self-efficacy, and physical fitness. The initial effects of the exercise intervention lasted at follow-up (T2 and T3). At 12-week follow up (T3), 80% of participants in the exercise condition still engaged in regular exercise, and further enhancements were seen for emotional exhaustion, overall fatigue, and sleep quality. CONCLUSIONS: These results underline the value of low-intensity exercise for university students with high levels of study-related fatigue. The follow-up effects that were found in this study imply that the intervention has the potential to promote regular exercise and accompanying beneficial effects in the longer run. TRIAL REGISTRATION: Netherlands Trial Register NTR4412.

Getting better, but not well: A 1.5 year follow-up of cognitive performance and cortisol levels in clinical and non-Clinical burnout.

The purpose was to reexamine cognitive performance and cortisol levels of initial clinical burnout patients, non-clinical burnout individuals, and healthy controls. After 1.5-years of the initial measurement, clinical burnout patients showed a reduction of burnout symptoms and general physical and psychological complaints, but these were still elevated compared with controls. Nonetheless, they continued to report cognitive problems and still showed a minor impaired cognitive test performance. However, they no longer reported larger subjective costs associated with cognitive test performance and their cortisol awakening response (CAR) returned to a normal level. Compared with controls, non-clinical burnout individuals still reported the same, elevated, level of burnout symptoms, general physical and psychological complaints, and cognitive problems. Their cognitive test performance and associated subjective costs remained normal. However, they seemed to continue to display a lowered CAR. To conclude, after 1.5-years, clinical burnout patients got better, but not 'well', and non-clinical burnout individuals remained not 'well'.

Shifts in attention during mental fatigue: Evidence from subjective, behavioral, physiological, and eye-tracking data.

There is an increasing amount of evidence that during mental fatigue, shifts in motivation drive performance rather than reductions in finite mental energy. So far, studies that investigated such an approach have mainly focused on cognitive indicators of task engagement that were measured during controlled tasks, offering limited to no alternative stimuli. Therefore it remained unclear whether during fatigue, attention is diverted to stimuli that are unrelated to the task, or whether fatigued individuals still focused on the task but were unable to use their cognitive resources efficiently. With a combination of subjective, EEG, pupil, eye-tracking, and performance measures the present study investigated the influence of mental fatigue on a cognitive task which also contained alternative task-unrelated stimuli. With increasing time-on-task, task engagement and performance decreased, but there was no significant decrease in gaze toward the task-related stimuli. After increasing the task rewards, irrelevant rewarding stimuli where largely ignored, and task engagement and performance were restored, even though participants still reported to be highly fatigued. Overall, these findings support an explanation of less efficient processing of the task that is influenced by motivational cost/reward tradeoffs, rather than a depletion of a finite mental energy resource. (PsycINFO Database Record