Psychomotor Vigilance Task Research Articles

Analysis of Head Micromovements and Body Posture for Vigilance Decrement Assessment

Vigilance refers to the capability of humans to respond accordingly to relevant and unpredictable tasks and surrounding environment changes over prolonged periods of time. Identifying vigilance decrements can, therefore, have huge and vital impacts on several operational environments in which a simple slip of mind or a deficit in attention can bear life-threatening and disastrous consequences. Several methodologies have been proposed to assess and characterize vigilance, and the results have indicated that the sole measure of performance and self-reports are not enough to obtain reliable and real-time vigilance measure. Nowadays, monitoring head and body movements to obtain information about performance in daily activities, health conditions, and mental states has become very simple and cheap due to the miniaturization of inertial measurement units and their widespread integration into common electronic devices (e.g., smart glasses, smartwatches). The present study aimed to understand the relationship between head micromovements and body posture changes to vigilance decrease while performing the psychomotor vigilance task. The results highlighted that head micromovements can be employed to track vigilance decrement during prolonged periods of time and discriminate between conditions of high or low vigilance.

Effects of total sleep deprivation on performance in a manual spacecraft docking task

Sleep deprivation and circadian rhythm disruptions are highly prevalent in shift workers, and also among astronauts. Resulting sleepiness can reduce cognitive performance, lead to catastrophic occupational events, and jeopardize space missions. We investigated whether 24 hours of total sleep deprivation would affect performance not only in the Psychomotor Vigilance Task (PVT), but also in a complex operational task, i.e. simulated manual spacecraft docking. Sixty-two healthy participants completed the manual docking simulation 6df and the PVT once after a night of total sleep deprivation and once after eight hours of scheduled sleep in a counterbalanced order. We assessed the impact of sleep deprivation on docking as well as PVT performance and investigated if sustained attention is an essential component of operational performance after sleep loss. The results showed that docking accuracy decreased significantly after sleep deprivation in comparison to the control condition, but only at difficult task levels. PVT performance deteriorated under sleep deprivation. Participants with larger impairments in PVT response speed after sleep deprivation also showed larger impairments in docking accuracy. In conclusion, sleep deprivation led to impaired 6df performance, which was partly explained by impairments in sustained attention. Elevated motivation levels due to the novelty and attractiveness of the task may have helped participants to compensate for the effects of sleepiness at easier task levels. Continued testing of manual docking skills could be a useful tool both to detect sleep loss-related impairments and assess astronauts’ readiness for duty during long-duration missions.

Impact on health outcomes associated with changing the clock 1 hour during fall and spring transitions in the Southern Hemisphere.

Changing the clocks seasonally is potentially harmful because it interferes with normal daytime activities. Studies aimed at quantifying this association are scant. The objective of this study was to determine the effects of 1 year's worth of changing the clocks (fall and spring transitions) on healthy young men located in the Southern Hemisphere in South America. We performed an observational prospective study. Thirty healthy male university students were evaluated from 2 weeks before to 2 weeks after both the fall and spring transitions. We administered an overall sleep questionnaire, assessed quality of life, recorded 7-day wrist actigraphy, and had participants perform a psychomotor vigilance task. We defined the 1-hour clock change as the primary exposure and the change in psychomotor vigilance task lapses of 500 milliseconds or more in response time as our primary outcome. Changes were evaluated by the Wilcoxon rank test (significance: P < .05). After the fall transition, we found a significant worsening in psychomotor vigilance task performance (median [interquartile range], 9.9 [6.0-14.3] lapses of ≥ 500 milliseconds in response time at baseline vs 16.8 [8.2-28.0] after transition; P < .002). Additionally, we found a median loss of about 1 hour of total sleep time and time in bed after the fall transition. Furthermore, participants presented with insomnia. Performance on the psychomotor vigilance task was also affected after the spring transition (16.7 [10-23] vs 23 [12.2-32.2]; P < .001). A decrease in performance in neurocognitive tests was found after both time transitions. The transition led to insomnia and a significant worsening of sleep variables. Labarca G, Henriquez-Beltrán M, Sanhueza R, etal. Impact on health outcomes associated with changing the clock 1 hour during fall and spring transitions in the Southern Hemisphere. J Clin Sleep Med. 2024;20(6):887-893.

Effects of Mind-Body Qigong Exercise on Overall Health, Fatigue/Sleep, and Cognition in Older Chinese Immigrants in the US: An Intervention Study with Control.

Culturally relevant exercises may help improve health and address disparities faced by older immigrants due to language and cultural barriers. Few studies have focused on such exercise interventions among older Chinese immigrants at US daycare centers. We conducted a 10-week nonrandomized controlled trial in older Chinese immigrants in Philadelphia, US. The intervention group practiced Chinese Qigong (Baduanjin) 5 days a week guided by trained research assistants and video instructions. The control group maintained their usual daily activities. We collected self-report assessments on overall health, sleep, and fatigue and implemented two computerized cognitive tests measuring psychomotor vigilance task (PVT) and memory twice, preintervention and postintervention. Repeated measures general linear model (GLM) and paired samples t-tests were used for data analyses. Eighty-eight older adults (Qigong, n = 53; control, n = 35) with an average age of 78.13 (SD = 5.05) were included. Groups showed no significant differences at baseline evaluation. After the 10-week exercise, the intervention group showed significant improvements in overall health (p=0.032), fatigue (p < 0.001), and cognitive functions including memory (p=0.01), response speed (p=0.002), and response time (p=0.012) on the PVT, as well as marginally significant benefits in sleep (p=0.058). Between-group comparisons identified significant group-by-time interactions in health (p=0.024), sleep (p=0.004), fatigue (p=0.004), and memory (p=0.004). We revealed significant positive effects of Qigong in older Chinese immigrants across multiple health domains. Findings highlight the potential of a culturally relevant exercise in addressing health disparities.

Lichttherapiebrillen während der Nachtschicht: eine Feldstudie

Abstract Background Night shift work leads to severe short- and long-term side effects, posing a risk to personal and occupational safety. Objective This study aimed to test the effects of blue-enriched light-emitting glasses on sleepiness, alertness, and sustained attention during the early morning hours of night shift work. Methods To remedy the risks of reduced alertness, sustained attention, and increased sleepiness in a single-blind study design, Luminette® 3 (Lucimed SA, Wavre, Belgium) glasses emitting blue-enriched light (BL) were tested from 05:00 to 05:30 during night shift work in 21 participants at a sleep laboratory, and the effects were compared with those of glasses emitting sham dim red light (DRL). Sleepiness was rated hourly from 21:00 to 07:30 using the Karolinska Sleepiness Scale, while alertness was assessed using the PC Psychomotor Vigilance Task before and after the intervention. At the end of the night shift, sustained attention (using the computerized Mackworth Clock Test), comfort ratings, and fatigue were measured. Statistical analyses were conducted using the Friedman and Wilcoxon signed-rank tests. Results Sleepiness increased significantly throughout the night and was not significantly reduced after the intervention, with a more prolonged reduction using BL. Compared with using DRL, using BL revealed no clear benefit in terms of alertness or sustained attention, yet comfort ratings were slightly better, without any negative side effects. Conclusion In the current study, BL glasses were not clearly superior to DRL glasses in ameliorating the negative side effects of night shift work. Despite some limitations, however, this field study showed high ecological validity and demonstrated the convenient use of an intervention that is easy to implement in a realistic workplace setting.

Utility of the psychomotor vigilance task in screening for obstructive sleep apnoea.

The study aimed to assess the performance of the PVT in patients with suspected OSA, evaluate its role in population screening for OSA. The NoSAS, STOP-Bang, ESS scores and PVT tests were performed after suspected OSA patients' admission, followed by PSG. Then we compared the PVT results, calculated the sensitivity, specificity and ROC curve of PVT, and analyzed the accuracy of STOP-Bang and NoSAS questionnaire combined with PVT in predicting OSA. A total of 308 patients were divided into four groups based on AHI: primary snoring (2.74 ± 1.4 events/h, n = 37); mild OSA (9.96 ± 3.25 events/h, n = 65); moderate OSA (22.41 ± 4.48 events/h, n = 76); and, severe OSA (59.42 ± 18.37 events/h, n = 130). There were significant differences in PVT lapses (p < 0.001) and reaction time (RT, p = 0.03) among the four groups. The PVT lapses and RT were positively correlated with AHI (p < 0.001) and ODI (p < 0.001), and negatively correlated with LSpO2 (p < 0.001). When diagnosing OSA (AHI ≥ 5 events/h), the AUCs of PVT, ESS, STOP-Bang, and NoSAS were 0.679, 0.579, 0.727, and 0.653, respectively; the AUCs of STOP-Bang and NoSAS combined with PVT increased. After combined PVT, the diagnostic specificity of STOP-Bang and NoSAS at nodes with AHI ≥ 5, ≥ 15 and ≥ 30 events/h increased to varying degrees. Patients with OSA exhibited impairment in the PVT, and the combination of the PVT and STOP-Bang or NoSAS scores can improve the diagnostic efficacy and specificity for OSA.

CHANGES IN FUNCTIONAL CONNECTIVITY FOLLOWING INTENSIVE ATTENTION TRAINING IN PATIENTS WITH TRAUMATIC BRAIN INJURY. A PILOT STUDY.

To explore functional connectivity after intensive attention training in the chronic phase after traumatic brain injury as clinical evidence indicates that intensive attention training improves attention dysfunction in persons with traumatic brain injury. A case series study. Two young adults, 13- and 18-months post traumatic brain injury, with traumatic brain injury induced attention deficits were assigned to 20 h of intensive attention training and neuroimaging. Functional magnetic resonance imaging during a psychomotor vigilance test was conducted pre- and post-intervention. The neuroimaging indicated both increased and decreased connectivity density in frontal, posterior and subcortical brain regions, for some regions with separate change patterns for left and right hemisphere respectively, and an overall reduction in variability in functional connectivity. The changed and decreased variability of functional connectivity in various brain regions, captured by fMRI during a psychomotor vigilance test after direct attention training in a small sample of persons with traumatic brain injury, suggests further studies of functional connectivity changes in neural networks.

Tracking the Recovery of a Mild Traumatic Brain Injury Patient utilizing a 60 s Combined Functional Near-Infrared Spectroscopy and Psychomotor Testing Approach A Case Study

Identifying and tracking the recovery of patients with mild traumatic brain injuries (mTBI) has remained elusive due to the lack of non-invasive, objective neuroimaging techniques. The purpose of this case study was to provide a proof of concept for performing a combined functional near-infrared spectroscopy (fNIRS) and 60-s psychomotor vigilance testing (60-s PVT) that can identify and track the recovery of a patient with a mTBI. The patient was a 19-year-old female acrobatics and tumbling athlete who was kicked in the left temple by a teammate. Video footage of the injury was utilized to determine the region of impact and weekly fNIRS and 60-s PVT assessments were performed throughout the 10 weeks of recovery. The patient was cleared for activity based upon symptoms at week 7; however, the patient reported increased symptomology during weeks 7 and 8 following exercise. Our fNIRS neuroimaging technique was able to detect the systemic physiological responses associated with mitochondrial dysregulation and oxygen extraction fraction at weeks 1 to 8. Based on our findings, the patient remained injured at week 8, and that the physical activity performed at weeks 7 and 8 may have regressed recovery and induced additional dysfunction resulting in increased recovery time. In conclusion, we were able to identify and track the recovery of our patient with a mTBI using our non-invasive combined fNIRS and 60-s PVT approach. Results provided real time physiological responses associated with the injury throughout the recovery process.

Consuming Caffeinated or Non-Caffeinated Energy Shots has No Effect on Mood or Performance

Introduction: The purpose of this investigation was to determine the effects of two different energy drinks on mood as well as mental and physical performance. Methods: In a randomized, double-blind, placebo-controlled investigation, subjects (n=60, 22 male, 38 female) were assigned to a caffeinated energy shot (Alpha Brain), a non-caffeinated energy shot (Ginger Rescue), or a placebo with no caffeine. Subjects were pre-tested on the psychomotor vigilance task (PVT), which is a measure of sustained attention, Profile of Mood States, and handgrip strength. Consequently, they consumed either the Alpha Brain shot, Ginger Rescue shot, or the placebo. One hour post-consumption, the assessments were repeated. Results: There were no between-group differences (p&gt;0.05) for any of the assessments regarding the change score (M±SD): PVT – Alpha Brain -3±15 msec, Ginger Rescue -21±60 msec, Placebo 1±21 msec; Total mood disturbance score – Alpha Brain -7.0±14.5, Ginger Rescue -4.1±11.1, Placebo -0.7±8.5; Peak handgrip – Alpha Brain 0.3±3.5 kg, Ginger Rescue 0.3±4.5 kg, Placebo -0.6±3.1 kg. Conclusions: The acute consumption of an energy shot, regardless of whether it is caffeinated, did not affect mood, handgrip strength, or sustained attention.

Cognitive performance of air personnel following sleep deprivation.

Air forces have developed several methods for reducing fatigue-related accidents. In the Israeli Air Force, the "Dead Tired" workshop was developed with the purpose of presenting aircrew with their objective performance under sleep deprivation conditions. The aim of this study was to examine the cognitive abilities of both aircrew and unmanned aerial vehicle operators, both objectively and subjectively. All Israeli aircrew and unmanned aerial vehicle operators participated in a "Dead Tired" workshop. During the workshop, the participants performed the Psychomotor Vigilance Task, a task that tests their attention abilities, while gathering information on their subjective sleepiness in the form of a Karolinska Sleepiness Scale. Data of 366 participants (25 females), of whom 187 were unmanned aerial vehicle operators and 179 were aircrew, were obtained; and the mean age was 21.8 ± 1.2 years (range 19-26 years). A significant decline in task performance was seen following 20 hr of wakefulness in both unmanned aerial vehicle operators and aircrew (p < 0.001). Unmanned aerial vehicle operators' performance was significantly better throughout the majority of the workshop (p < 0.001). Recovery after the full-night's sleep was seen for unmanned aerial vehicle operators, but not for aircrew (p = 0.008). A high correlation was seen between Psychomotor Vigilance Task performance and Karolinska Sleepiness Scale responses (correlation coefficient = 0.93). Sleep deprivation negatively impacted the performance of both groups of participants. Unmanned aerial vehicle operators were found to be more resilient to the effects of sleep deprivation and were quicker to recover in comparison to aircrew.

Comparison of effects of modafinil and caffeine on fatigue-vulnerable and fatigue-resistant aircrew after a limited period of sleep deprivation.

Introduction: Literature suggests pilots experience fatigue differently. So-called fatigue-resistant or -vulnerable individuals might also respond differently to countermeasures or stimulants. This study, which is part of a larger randomized controlled clinical trial, aims to investigate the effect of caffeine and modafinil on fatigue-resistant and -vulnerable pilots. Methods: This study included 32 healthy employees of the Royal Netherlands Air Force, who completed three test days, separated by at least 7days. After a regular work day, the subjects were randomly administered either 300mg caffeine, 200mg modafinil or placebo at midnight. Hereafter the subjects performed the psychomotor vigilance test (PVT), vigilance and tracking test (VigTrack) and Stanford sleepiness scale (SSS) six times until 8 a.m. the next day. Subjects were ranked on the average number of lapses on the PVT during the placebo night and divided into three groups: fatigue-vulnerable (FVUL), -intermediate (FINT) and -resistant (FRES), with 11, 10 and 11 subjects in each group, respectively. Area under the curve (AUC) of the PVT, VigTrack and SSS during the test nights were calculated, which were used in univariate factorial analysis of variance (ANOVA). Tukey's HSD post hoc tests were used to differentiate between the groups. Results: A significant effect of treatment was found in the ANOVA of both PVT parameters, VigTrack mean reaction time and SSS. There was a statistically significant effect of fatigue group on all PVT parameters and VigTrack mean percentage omissions, where FINT and FRES scored better than FVUL. There was a significant interaction effect between treatment and fatigue group for PVT number of lapses. This is congruent for the AUC analyses in which for all parameters (except for the SSS) the performance of the FVUL group was consistently worse than that of the FINT and FRES groups. Discussion: This study demonstrates that the performance of individuals with different fatigue tolerances are differently affected by simulants after a limited period of sleep deprivation. The classification of fatigue tolerance through PVT lapses when sleep deprived seems to be able to predict this.

Estimating vigilance from the pre-work shift sleep using an under-mattress sleep sensor.

Predicting vigilance impairment in high-risk shift work occupations is critical to help to reduce workplace errors and accidents. Current methods rely on multi-night, often manually entered, sleep data. This study developed a machine learning model for predicting vigilance errors based on a single prior sleep period, derived from an under-mattress sensor. Twenty-four healthy volunteers (mean [SD] age = 27.6 [9.5] years, 12 male) attended the laboratory on two separate occasions, 1 month apart, to compare wake performance and sleep under two different lighting conditions. Each condition occurred over an 8 day protocol comprising a baseline sleep opportunity from 10 p.m. to 7 a.m., a 27 h wake period, then daytime sleep opportunities from 10 a.m. to 7 p.m. on days 3-7. From 12 a.m. to 8 a.m. on each of days 4-7, participants completed simulated night shifts that included six 10 min psychomotor vigilance task (PVT) trials per shift. Sleep was assessed using an under-mattress sensor. Using extra-trees machine learning models, PVT performance (reaction times <500 ms, reaction, and lapses) during each night shift was predicted based on the preceding daytime sleep. The final extra-trees model demonstrated moderate accuracy for predicting PVT performance, with standard errors (RMSE) of 19.9 ms (reaction time, 359 [41.6]ms), 0.42 reactions/s (reaction speed, 2.5 [0.6] reactions/s), and 7.2 (lapses, 10.5 [12.3]). The model also correctly classified 84% of trials containing ≥5 lapses (Matthews correlation coefficient = 0.59, F1 = 0.83). Model performance is comparable to current fatigue prediction models that rely upon self-report or manually entered data. This efficient approach may help to manage fatigue and safety in non-standard work schedules.

The effect of total sleep deprivation on working memory: evidence from diffusion model.

Working memory is crucial in human daily life and is vulnerable to sleep loss. The current study investigated the impact of sleep deprivation on working memory from the information processing perspective, to explore whether sleep deprivation affects the working memory via impairing information manipulation. Thirty-seven healthy adults attended two counterbalanced protocols: a normal sleep night and a total sleep deprivation (TSD). The N-back and the psychomotor vigilance task (PVT) assessed working memory and sustained attention. Response time distribution and drift-diffusion model analyses were applied to explore cognitive process alterations. TSD increased the loading effect of accuracy, but not the loading effect of response time in the N-back task. TSD reduced the speed of information accumulation, increased the variability of the speed of accumulation, and elevated the decision threshold only in 1-back task. Moreover, the slow responses of PVT and N-back were severely impaired after TSD, mainly due to increased information accumulation variability. The present study provides a new perspective to investigate behavioral performance by using response time distribution and drift-diffusion models, revealing that sleep deprivation affected multicognitive processes underlying working memory, especially information accumulation processes.

Ad libitum caffeine consumption, cognitive performance, and sleep in special forces soldiers during a 96-h combat exercise.

This observational study investigated the effects of sleep deprivation and ad libitum caffeine consumption on cognitive performance, risk behavior, and mood among 28 Israeli Special Forces (SF) soldiers (mean age: 20.57 ± 0.92 years) during a 96-hour combat exercise. Actigraphy was used to monitor sleep and activity; cognitive function, risk-taking propensity, mood states, and self-reported sleepiness were assessed using the Psychomotor Vigilance Task (PVT), Evaluation of Risks Scale (EVAR), Profile of Mood States (POMS), Karolinska Sleepiness Scale (KSS); and caffeine consumption by questionnaire at 0, 50, and 96 hours. For analyses, participants were divided into Low (<400 mg) and High (≥400 mg) caffeine consumption groups. The soldiers hiked 108.5 ± 0.52 km and slept for 12.7 ± 0.5 h, with a notable transition from multiple short sleep epochs in the initial 50 hours to a consolidated 5-hour sleep period subsequently. In the High caffeine group, PVT reaction time was faster (p = 0.024) compared to the Low caffeine group, with fewer premature response errors (p = 0.026). However, this group showed increased risk-taking (p = 0.037), particularly reduced Self-Control (p = 0.010). No significant impact of ad libitum caffeine intake on mood was observed. However, degradation over the course of the exercise in both groups in mood states, including anger, fatigue, tension, and vigor, was noted (p < 0.05). KSS scores increased significantly at 50 and 96 h (p < 0.001). These results suggest that while caffeine enhances cognitive function, its ad libitum consumption did not consistently improve these measures in this cohort of SF soldiers. The study highlights the complex relationship between sleep deprivation and caffeine intake and their combined effects on soldiers' cognitive and behavioral functions, indicating a need for evidence-based caffeine use guidelines for using caffeine in military settings.

Effects of 8 weeks pre-season training on physical fitness, heart rate variability and cognition in women soccer players

The aim of this study was to explore the variations (pre-post) of (i) Anthropometric measures: weight, body mass index, lean and muscle mass, (ii) Physical fitness: countermovement jump (CMJ) and VO2max, (iii) heart rate variability (HRV) (recumbent and sitting): mean RR, RMSSD, NN50 and NN50 %, (iv) Psychomotor Vigilance Task, and v) SART: ACC Go, ACC NoGo and reaction times in semi-professional women soccer players from the second division of the Spanish League. The analysis indicated that lean mass improved after the observation period (p = .05, d = −0.38), while no other significant changes in anthropometric measures were observed. Additionally, CMJ and aerobic power were also improved (p<.01, d>0.50). The RMSSD [recumbent (d = −0.73) and sitting (d = −0.52)] and NN50 [recumbent (d = −0.69) and sitting (d = −0.70)] increased after the period of observation (p < .05). Reaction time also significantly improved after the period of observation [PVT (d = 0.42) and SART (d = −0.89)]. Correlations performed between measures revealed that smaller body mass and body mass index were largely associated with greater NN50 (r < 0.83, p = .001). Additionally, greater CMJ and aerobic fitness were associated with greater HRV [recumbent (r = −51, p = .001) and sitting (r = −0.60, p = .01). The main findings of this study were that there was no relationship between cognitive performance and physical fitness, but HRV was related to body composition and physical fitness during the pre-season in women soccer players.

The evaluation of cEEGrids for fatigue detection in aviation.

Operator fatigue poses a major concern in safety-critical industries such as aviation, potentially increasing the chances of errors and accidents. To better understand this risk, there is a need for noninvasive objective measures of fatigue. This study aimed to evaluate the performance of cEEGrids, a type of ear-EEG, for fatigue detection by analyzing the alpha and theta power before and after sleep restriction in four sessions on two separate days, employing a within-participants design. Results were compared to traditional, highly validated methods: the Karolinska Sleepiness Scale (KSS) and Psychomotor Vigilance Task (PVT). After sleep restriction and an office workday, 12 participants showed increased alpha band power in multiple electrode channels, but no channels correlated with KSS scores and PVT response speed. These findings indicate that cEEGrids can detect differences in alpha power following mild sleep loss. However, it should be noted that this capability was limited to specific channels, and no difference in theta power was observed. The study shows the potential and limitations of ear-EEG for fatigue detection as a less invasive alternative to cap-EEG. Further design and electrode configuration adjustments are necessary before ear-EEG can be implemented for fatigue detection in the field.

The effect of a dynamic lighting schedule on neurobehavioral performance during a 45-day simulated space mission.

We previously reported that during a 45-day simulated space mission, a dynamic lighting schedule (DLS) improved circadian phase alignment and performance assessed once on selected days. This study aimed to evaluate how DLS affected performance on a 5-minute psychomotor vigilance task (PVT) administered multiple times per day on selected days. Sixteen crewmembers (37.4 ± 6.7 years; 5F) underwent six cycles of 2 × 8-hour/night followed by 5 × 5-hour/night sleep opportunities. During the DLS (n = 8), daytime white light exposure was blue-enriched (~6000K; Level 1: 1079, Level 2: 76 melanopic equivalent daytime illuminance (melEDI) lux) and blue-depleted (~3000-4000K; L1: 21, L2: 2 melEDI lux) 3 hours before bed. In the standard lighting schedule (SLS; n = 8), lighting remained constant (~4500K; L1: 284, L2 62 melEDI lux). Effects of lighting condition (DLS/SLS), sleep condition (5/8 hours), time into mission, and their interactions, and time awake on PVT performance were analyzed using generalized linear mixed models. The DLS was associated with fewer attentional lapses (reaction time [RT] > 500 milliseconds) compared to SLS. Lapses, mean RT, and 10% fastest/slowest RTs were worse following 5 compared to 8 hours of sleep but not between lighting conditions. There was an effect of time into mission on RTs, likely due to sleep loss. Overall performance differed by time of day, with longer RTs at the beginning and end of the day. There were more lapses and slower RTs in the afternoon in the SLS compared to the DLS condition. Future missions should incorporate DLS to enhance circadian alignment and performance. This paper is part of the Sleep and Circadian Rhythms: Management of Fatigue in Occupational Settings Collection.

The Influence of a Warm-Up on Vigilance in University Students.

The present study aimed to analyze the effects of conducting a warm-up (WC) or not (WWC) on students of the Science Degree in Physical Activity and Sport before starting a practical class. Thirty-two students of the Science Degree in Physical Activity and Sport (age: 22.38 ± 1.81 years; height: 176.09 ± 8.52 cm; weight: 22.38 ± 1.81 kg; body fat: 25.17 ± 3.20%) participated in a counterbalanced cross-sectional study in which three conditions were tested: (a)basal lineal, (b)WC, and (c)WWC. Participants recorded longer times (worse performance) in the Illinois dribbling test (basal lineal condition [20.17 ± 1.35], WWC [20.13 ± 1.37], and WC [19.32 ± 1.35]) and the Psychomotor Vigilance Task test (basal lineal condition [397.88 ± 75.98ms]; WWC [412.19 ± 91.39ms], and WC [368.53 ± 68.65ms]). The warm-up prior to physical activity classes had positive effects on vigilance linked to executive functioning, and physical performance. In this sense, more research on different types of warm-up may be in order to contrast them with each other, as well as to carry out attention measurements according to the content to be imparted after the warm-ups. The present study represents a big opportunity for all physical education teachers due to warm-up is a crucial aspect that occurs in all practical sessions, also linked to the attention processes and motivational factors of the students.

Effects of a simulated maritime shift schedule on vigilance, sleep, and sleepiness

ABSTRACT Shift work is associated with circadian misalignment, which causes sleep loss, impairs performance, and increases the risk of accidents. Shorter, more frequently shifting watch schedules, widely used in industries such as maritime operation, defense, and mining, may mitigate these risks by reducing shift length and providing sleep opportunities for all workers across the biological night. However, the effects of frequently shifting work on sleep and performance still need to be clarified. The current study investigated the vigilance, sleepiness, and sleep patterns of fifteen participants who lived in a controlled and confined laboratory that mimicked a maritime environment for 14 d following a simulating frequent shift schedule. The results of psychomotor vigilance tasks (PVT) suggest that this shift schedule may lead to an accumulation of vigilance detrimental across watch days, with both reaction speed impairment and error growth. Furthermore, the circadian phase significantly affects PVT performance, with the afternoon shift section showing relatively better performance. Overall, more working hours per day resulted in poorer PVT performance. As the shift progressed, total sleep duration reduced slightly, and wake after sleep onset (WASO) increased. Sleep during the biological night was generally longer than sleep in the daytime. Less on-watch time was linked to longer overall sleep duration. Additionally, although the subjective sleepiness obtained by the Karolinska Sleepiness Scale (KSS) varied insignificantly across days, the KSS score was negatively correlated with PVT performance. This research can serve as a foundation for developing countermeasures to mitigate frequently shifting schedules’ potentially detrimental effects and safety risks.

Acute smartphone use impairs vigilance and inhibition capacities

Smartphones are now in very widespread use, and concerns have arisen about potential detrimental effects, even with acute use. These adverse consequences are often linked to the emergence of mental fatigue. While the cognitive implications of fatigue are well-documented, knowledge about the specific influence of acute smartphone use on cognitive performance remains scarce. The aim of this study was therefore to investigate the impact of acute smartphone use on cognitive performance. It included two experiments: one designed to assess the impact of smartphone use on vigilance, and the other focusing on evaluating inhibition capacities. In Experiment 1, two groups of 40 participants completed a Psychomotor Vigilance Task (PVT) before and after using a smartphone for 45 min (experimental group), or before and after watching a documentary (control group). In Experiment 2, two groups of 40 participants were subjected to a similar experimental design but had to perform a Go/NoGo task instead of a PVT. Mental fatigue and drowsiness were evaluated with visual analog scales before and after smartphone use and watching a documentary. Results suggested that both watching a documentary and using a smartphone for 45 min increased subjective mental fatigue and drowsiness. Watching the documentary did not impair cognitive performance. Reaction times on the PVT and number of errors on NoGo trials in the Go/NoGo task were higher among the participants in the smartphone condition. These results indicate reduced vigilance and impaired inhibition capacities only after smartphone use. We conclude that acute smartphone use induces mental fatigue and decreases cognitive performance. Further research is needed to understand the mechanisms underlying this decline in cognitive performance.