Vigilance Task Research Articles

P077 Associations of sex, sleep, and circadian rhythms with performance in elite Australian Rules footballers

Abstract Introduction Poor sleep and circadian misalignment are associated with poorer performance. In elite Australian Rules football (ARF), both sex and professionalism could alter or exacerbate these associations. This study provides preliminary insights on how the relationships of sleep and circadian alignment with cognitive performance differ between male full-professional and female semi-professional elite ARF athletes. Methods Participants were 72 elite ARF athletes (42% female; M-age = 24.1±4.4 years). During pre-season, participants completed two weeks of sleep/wake monitoring via actigraphy, and a circadian phase assessment (dim light melatonin onset; DLMO) after one week. Cognitive performance testing (psychomotor vigilance task, PVT; and the balloon analogue risk task; BART) was conducted five times throughout this period. Results Preliminary findings suggest average total sleep time and sleep efficiency, sleep regularity, DLMO, and phase angle (interval between average sleep onset and DLMO) did not predict reaction time on the PVT, nor did sex moderate these relationships. After controlling for sex, longer sleepers demonstrated greater risk taking on the BART. Only among male athletes did larger angles predict greater risk taking. Discussion Elite ARF athletes, regardless of sex, sleep, or circadian alignment, have similar reaction times. Risk taking is greater among longer sleepers and in male athletes experiencing relatively delayed circadian phases. Where risk-taking has negative implications (e.g., injury and sporting errors), these findings identify at-risk groups. Few sex-specific findings may suggest that the semi-professional status of female ARF (and associated lifestyle factors such as scheduling and income) is not altering elite performance in controlled settings.

O073 The Relationship between Circadian type and Physical Activity on Cognitive Performance during Simulated Nightshifts: A Randomised Controlled Trial.

Abstract Introduction Physical activity might be a nonphotic strategy which could improve cognitive performance for nightshift workers. Innate characteristics like circadian type may also influence individual performance. Thus, this study explores the relationship between circadian type and physical activity on cognition over consecutive nightshifts. Methods Thirty-two healthy adults (age M±SD: 24.3±4.6 years; 19 females) participated in a 7-day laboratory study, with 5 nightshifts (2200-0600). Participants were randomised into the Breaking up sitting (BUS; n=19) or Sedentary (SED; n=13) condition. Overnight, BUS participants completed 3-min bouts of light-intensity walking every 30-min, while SED participants remained seated. At 2200, 0000, 0200, 0400 and 0600, participants completed the 10-min Psychomotor Vigilance Task (mean RRT). Participants completed the 11-item revised Circadian Type Inventory (factor 1: rigid/flexible; factor 2: languid/vigorous), resulting in four-subgroups (rigid; n= 12, flexible; n= 11, and languid; n= 11, vigorous; n= 13). Participants may only be one type from either factor (i.e. rigid and vigorous). Results Linear mixed models showed a significant 3-way interaction between nightshift (1-5), condition (BUS, SED), and circadian type (rigid/flexible) for mean RRT (p=0.03), such that flexible types in the Breaking up sitting condition outperformed Sedentary flexible types and Breaking up sitting rigid types, with performance worse on the first nightshift. There were no significant interactions between nightshift, condition and circadian type (languid/vigorous). Discussion Breaking up sitting improved performance for flexible types over rigid types. These findings have significant implications for nightshift rostering, suggesting that incorporating breaking up sitting may optimise cognitive performance, and therefore work efficiency.

P104 The Impact of Total Sleep Deprivation on Performance in the Esport ‘Rocket League’.

Abstract Preliminary findings from this study were presented as a poster (P376) at Sleep Europe 2022 (https://doi.org/10.1111/jsr.13740). Introduction Sleep loss is presumed by academics and esport (organised competitive video-game play) athletes to be an in-game esport performance hindrance, primarily due to its well understood effects on multiple domains of cognitive performance. However, the effects of acute sleep loss specifically on esports performance have not been explored. We aimed to elucidate whether total sleep deprivation degrades in-game performance in the popular esport ‘Rocket League’. Methods Forty habitual Rocket League players were paired according to in-game ability level (twenty pairs), with one assigned to a control group (CON) and the other assigned to an intervention group (TSD). Two test sessions took place, in which paired players completed subjective and cognitive performance measures, and played seven Rocket League matches against one another. In one session, both players in a pair were well rested, while in the other, CON was rested while TSD was sleep deprived. Results Acute total sleep deprivation resulted in higher self-reported sleepiness, lower alertness and motivation, poorer performance on the Psychomotor Vigilance Task (PVT) and two-choice component of the Category Switch Task (CST). Despite this, overall in-game esport performance did not worsen due to sleep deprivation, although exploratory analysis suggests potential in-game strategy change. Discussion Our findings do not suggest that sleep loss is inconsequential for esport athletes, but rather suggest that acute bouts of sleep loss of similar/lesser severity may not be a primary concern for in-game esports performance.

Effect of total sleep deprivation on effective EEG connectivity for young male in resting-state networks in different eye states.

Many studies have investigated the effect of total sleep deprivation (TSD) on resting-state functional networks, especially the default mode network (DMN) and sensorimotor network (SMN), using functional connectivity. While it is known that the activities of these networks differ based on eye state, it remains unclear how TSD affects them in different eye states. Therefore, we aimed to examine the effect of TSD on DMN and SMN in different eye states using effective functional connectivity via isolated effective coherence (iCoh) in exact low-resolution brain electromagnetic tomography (eLORETA). Resting-state electroencephalogram (EEG) signals were collected from 24 male college students, and each participant completed a psychomotor vigilance task (PVT) while behavioral data were acquired. Each participant underwent 36-h TSD, and the data were acquired in two sleep-deprivation times (rested wakefulness, RW: 0 h; and TSD: 36 h) and two eye states (eyes closed, EC; and eyes open, EO). Changes in neural oscillations and effective connectivity were compared based on paired t-test. The behavioral results showed that PVT reaction time was significantly longer in TSD compared with that of RW. The EEG results showed that in the EO state, the activity of high-frequency bands in the DMN and SMN were enhanced compared to those of the EC state. Furthermore, when compared with the DMN and SMN of RW, in TSD, the activity of DMN was decreased, and SMN was increased. Moreover, the changed effective connectivity in the DMN and SMN after TSD was positively correlated with an increased PVT reaction time. In addition, the effective connectivity in the different network (EO-EC) of the SMN was reduced in the β band after TSD compared with that of RW. These findings indicate that TSD impairs alertness and sensory information input in the SMN to a greater extent in an EO than in an EC state.

Delayed melatonin circadian timing, lower melatonin output, and sleep disruptions in myopic, or short-sighted, children.

This study investigated the differences in melatonin circadian timing and output, sleep characteristics, and cognitive function in myopic and non-myopic (or emmetropic) children, aged 8-15 years. Twenty-six myopes (refractive error [mean ± standard error mean] -2.06 ± 0.23 diopters) and 19 emmetropes (-0.06 ± 0.04 diopters), aged 11.74 ± 2.31 years were recruited. Circadian timing was assessed using salivary dim-light melatonin onset (DLMO), collected half-hourly for 7 hours, beginning 5 hours before and finishing 2 hours after individual average sleep onset in a sleep laboratory. Nocturnal melatonin output was assessed via aMT6s levels from urine voids collected from 05:30 pm to 8:00 am the following morning. Actigraphy-derived objective sleep timing were acquired for a week prior to the sleep laboratory visit. Cognitive assessments of sustained attention (using psychomotor vigilance task [PVT]) and working memory (using digit spans) were performed on the night of sleep laboratory. Myopic children (9:07 pm ± 14 minutes) exhibited a DLMO phase-delay of 1 hour 8 minutes compared to emmetropes (7:59 pm ± 13 minutes), p = 0.002. aMT6s melatonin levels were significantly lower among myopes (18.70 ± 2.38) than emmetropes (32.35 ± 6.93, p = 0.001). Myopes also exhibited significantly delayed sleep onset, delayed wake-up time, poor and reduced sleep, and more evening-type diurnal preference than emmetropes (all p < 0.05). Finally, myopes showed a slower reaction time in the PVT (p < 0.05), but not digit span tasks at night. These findings suggest a potential association between circadian rhythm dysfunction and myopia in children.

Gamma Power as an Index of Sustained Attention in Simulated Vigilance Tasks.

Performance on the psychomotor vigilance test (PVT; Dinges & Powell, 1985)-a common index of sustained attention-is affected by the opposing forces of fatigue and sustained effort, where reaction times and error rates typically increase across trials and are sometimes offset by additional efforts deployed toward the end of the task (i.e., an "end-spurt"; cf. Bergum & Klein, 1961). In ACT-R (Adaptive Control of Thought-Rational; Anderson etal., 2004), these influences on task performance have been modeled as latent variables that are inferred from performance (e.g., Jongman, 1998; Veksler & Gunzelmann, 2018) without connections to directly observable variables. We propose the use of frontal gamma (γ) spectral power as a direct measure of vigilant effort and demonstrate its efficacy in modeling performance on the PVT in both the aggregate and inindividuals.

Effect of subconscious changes in bodily response on thought shifting in people with accurate interoception

Our thought states shift from one state to another from moment to moment. The relationship between the thought shifting and bodily responses is yet to be directly examined. This exploratory study examined the influence of cardiovascular reactivity and interoception—sensing an internal bodily state—on the shifting of thought states. Participants (N = 100, 70 women) completed two tasks: the heartbeat counting task (HCT) and the vigilance task (VT). We assessed their interoceptive accuracy through their performance on the HCT. The VT was a simple sustained attention task in which participants pressed a key when the target stimulus appeared and were asked to report their thoughts. We presented subliminal vibration stimuli to induce alterations in heart rate (i.e., vibration block). Results showed that participants with higher interoceptive accuracy reported more continuation of self-referential thought (about past episodes and future plans regarding themselves) during the vibration block than did those with lower interoceptive accuracy. These results suggest that individuals with higher interoceptive accuracy are more likely to be influenced by their subliminal bodily response, resulting in divergent attention from the task and intermittent self-referential thought.

The interference of negative emotional stimuli on semantic vigilance performance in a dual-task setting

A large body of previous research has shown that emotional stimuli have an advantage in a wide variety of cognitive processes. This was mainly observed in visual search and working memory tasks. Emotionally charged objects draw and hold attention, are remembered better, and interfere more with the completion of the primary task than neutral ones. Therefore, it seems reasonable to assume that emotional stimuli also greatly affect sustained attention and vigilance decrement. In the present research, we investigated whether emotional stimuli demand more attentional resources than neutral ones in a dual-task paradigm. We adopted the abbreviated semantic discrimination vigilance task and measured participants’ (N = 49) performance in a single-task and two dual-task settings. In the dual-task conditions, the visual semantic vigilance paradigm was combined with an auditory word recall task (with neutral or emotional stimuli). We found reduced vigilance and improved word recall performance in the emotional dual-task condition compared to the neutral dual-task and single-task conditions. The reduced performance was apparent throughout the task, while in the neutral conditions, participants’ performance first increased and then dropped as time progressed. To conclude, our results indicate that emotional stimuli not only have an advantage in cognitive processing but also demand more attentional resources continuously while it is present compared to neutral stimuli. These results are consistent with the emotionality effect theory and evolutionary accounts of the neural circuits underlying motivated behaviors associated with critical survival needs.

Impact of incomplete feedback on response bias

The goal of most laboratory studies is to produce a bias-free estimate of sensitivity. Forced-choice procedures with trial-by-trial feedback, equal a priori probability of signal occurrence, and a balanced pay-off matrix were designed to assess listener sensitivity with response bias forced to zero. (Green, 1960; Green and Swets, 1964; 1988). Real-world detection tasks rarely provide N-interval forced-choice opportunities. The probability of signal occurrence may vary from near zero in vigilance tasks to near 100% for some clinical testing. Further, many real-world listening situations do not lend themselves to trial-by-trial feedback. Davis (2015, 2017) conducted a single interval yes-no, tone-in-noise experiment measuring response bias with incomplete feedback. Liu (2020) used Bayesian analysis to account for participant variability in the Davis data. Results from different subjects were combined to draw inferences about the effect of each experimental condition on listener bias. As expected, complete feedback drives the response criteria toward the unbiased point, and incomplete feedback conditions result in various degrees of deviation from the optimal criterion. Critical incomplete feedback conditions included responses on signal trials, “yes” responses, and correct responses. Implications for the design of experiments intended to approximate listening conditions in realistic detection tasks are discussed.

Comparing the association between heavy metals and cognitive status and depression in miners and non-miners: A study from southeast of Iran

Heavy metal toxicity is a major public health crisis worldwide, especially in mining environments. The association between chronic heavy metals exposure and cognitive impairment has not been studied broadly in adults and mining fields. This study aimed to compare the association between arsenic (As), lead (Pb), and copper (Cu) concentration in blood and cognitive status and depression in copper miners and non-miners. Participants were selected from the Rafsanjan cohort study (RCS) as non-miners and miners from Sarcheshmeh Copper Complex. For evaluation of cognitive performance and creativity, comprehensive neurological tests were performed as follows: Mini-Mental Status Examination (MMSE), Paced Auditory Serial Addition Test (PASAT), Symbol Digit Modalities Test (SDMT), Psychomotor Vigilance Task (PVT), creativity tests including remote association task (RAT) and alternative uses task (AUT). Beck Depression Inventory-II was used to evaluate depression. Standard laboratory tests were also performed. Atomic absorption spectrophotometry was used to estimate the blood's concentration of As, Pb and Cu. We observed a significant difference between arsenic, lead, copper, and depression scores (all P < 0.001) in the two groups (miners and non-miners). Miners had a better performance in cognitive fields except in MMSE and PVT tests. Linear regression analyses showed that the lead had a negative association with the PVT test and depression score. The results suggest that the development of depression, cognitive impairments, and other health problems is possible in chronic heavy metal exposure, especially lead (Pb). Confirmation of our claim requires further study in the coming years.

A pilot study of light exposure as a countermeasure for menstrual phase-dependent neurobehavioral performance impairment in women

ObjectiveTo examine effects of menstrual phase and nighttime light exposure on subjective sleepiness and auditory Psychomotor Vigilance Task performance. MethodsTwenty-nine premenopausal women (12 =Follicular; 17 =Luteal) completed a 6.5-hour nighttime monochromatic light exposure with varying wavelengths (420-620 nm) and irradiances (1.03-14.12 µW/cm2). Subjective sleepiness, reaction time, and attentional lapses were compared between menstrual phases in women with minimal (<33%) or substantial (≥33%) light-induced melatonin suppression. ResultsWhen melatonin was not suppressed, women in the follicular phase had significantly worse reaction time (mean difference=145.1 ms, 95% CI 51.8-238.3, p < .001, Cohen’s D=1.9) and lapses (mean difference=12.9 lapses, 95% CI 4.37-21.41, p < .001, Cohen’s D=1.7) compared to women in the luteal phase. When melatonin was suppressed, women in the follicular phase had significantly better reaction time (mean difference=152.1 ms, 95% CI 43.88-260.3, p < .001, Cohen’s D=1.7) and lapses (mean difference=12.3 lapses, 95% CI 1.14-25.6, p < .01, Cohen’s D=1.6) compared to when melatonin was not suppressed, such that their performance was not different (p > .9) from women in the luteal phase. Subjective sleepiness did not differ by menstrual phase (mean difference=0.6, p > .08) or melatonin suppression (mean difference=0.2, p > .4). ConclusionsNighttime light exposure sufficient to suppress melatonin can also mitigate neurobehavioral performance deficits associated with the follicular phase. Despite the relatively small sample size, these data suggest that nighttime light may be a valuable strategy to help reduce errors and accidents in female shift workers.

Bipolar disorder and delayed sleep-wake phase disorder: Findings on sustained attention, sleep, and circadian rhythm parameters

BackgroundSleep and circadian rhythm disruptions can contribute to cognitive disturbances in bipolar disorder (BD); however, the profile of specific sleep/circadian phenotypes remains to be elucidated. The aim of our work is to compare sleep/circadian parameters and sustained attention between patients with BD and comorbid delayed sleep-wake phase disorder (BD-DSWPD), patients with BD without DSWPD comorbidity (BD-Control), and healthy controls (HC). MethodsBD patients (N = 70, BD-DWSPD N = 25, BD-Control N = 45) and HC (N = 86) were evaluated through actigraphy for sleep and circadian rhythm parameters, the Pittsburgh Sleep Quality Index for sleep quality, the reduced Morningness-Eveningness Questionnaire for chronotype and the Psychomotor Vigilance Task for sustained attention. ResultsThe BD-DSWPD diagnosis was associated with poorer self-reported sleep quality, lower sleep efficiency, higher wake after sleep onset, and later acrophase compared to both HC and BD-Control groups. BD-DSWPD was also associated with lower relative amplitude compared to HC. Regarding sustained attention variables, the diagnosis of BD-DSWPD was associated with increased response times compared to HC, while both BD-DSWPD and BD-Control were associated with major lapses than HC. LimitationsSample size and multivariate statistics not adjusted for pharmacological treatment. ConclusionsPatients with BD-DSWPD showed greater disturbances in sleep and circadian rhythm parameters compared to both HC and BD-Controls; moreover, BD-DSWPD showed increased response times compared to HC. Further studies are required to evaluate whether treatments focused on advancing the sleep phase may contribute to improving cognition, sleep, and circadian rhythmicity in patients with BD and comorbid DSWPD.

Comparing two relaxation procedures to ease fatigue in multiple sclerosis: a single-blind randomized controlled trial

BackgroundVarious relaxation procedures have been proposed to reduce fatigue in multiple sclerosis (MS). However, it is unknown, which type of relaxation has the largest effect on fatigue reduction and on autonomic nervous system (ANS) activity.ObjectiveWe aimed to compare two biofeedback-supported relaxation exercises: a deep breathing (DB) exercise and progressive muscle relaxation (PMR), which may ameliorate MS fatigue and alter ANS activity.MethodsWe performed a single-blind randomized clinical trial, introducing MS patients (n = 34) to the DB or PMR exercise. We first tested cardiovagal integrity, reflected by changes in heart rate variability (HRV) in response to DB. Participants then performed a fatigue-inducing vigilance task, followed by the DB or PMR. State fatigue was recorded consecutively at baseline, after the vigilance task, and after the relaxation exercise, along with HRV reflecting ANS activity.ResultsOnly patients assigned to the PMR group experienced a significant drop in fatigue, whereas both relaxation exercises changed ANS activity. MS patients showed the expected autonomic response during the cardiovagal reflex test. The vigilance task elevated short-term feelings of fatigue and significantly reduced HRV parameters of parasympathetic activity. Trait fatigue was negatively correlated with HRV during the second half of the vigilance task.ConclusionPMR alleviates short-term feelings of fatigue in persons with MS. The vigilance task in combination with HRV measurements may be helpful for evaluating relaxation procedures as a treatment of fatigue. Hereby, future studies should ensure longer and more frequent relaxation exercises and focus on patients with weak to moderate fatigue.Trial registrationTrial Registry: DRKS00024358.

Pharmacokinetics, pharmacodynamics and safety profile of the dual orexin receptor antagonist vornorexant/TS-142 in healthy Japanese participants following single/multiple dosing: Randomized, double-blind, placebo-controlled phase-1 studies.

The pharmacokinetics, pharmacodynamics and safety profile of vornorexant were investigated in healthy Japanese participants in three double-blind studies: a single ascending dose of 1-30 mg (Study 101; n = 6) and multiple ascending doses of 10-30 mg (Study 102; n = 6). Study 202 consisted of two steps: an open-label, 20 mg repeated-dose in non-elderly individuals (Step 1; n = 12) and a double-blind, 20 mg repeated-dose in elderly individuals (Step 2; n = 8/3 for vornorexant/placebo). Vornorexant was rapidly absorbed and eliminated under fasting conditions, with a time to maximum plasma concentration of 0.500-3.00 h (range) and elimination half-life of 1.32-3.25 h. The area under the plasma concentration-time curve (AUC) of vornorexant increased proportionally with dose increments. Sleepiness-related pharmacodynamic outcome changes (Karolinska sleepiness scale, digit symbol substitution test and psychomotor vigilance task) were generally increased with dose increments at 1 and 4 h post-dose, whereas no consistent dose-related changes were detected the next morning. Food intake did not affect the maximum observed plasma concentration of vornorexant but increased the AUC0-inf . Exposure in elderly individuals was generally comparable to that in non-elderly individuals. Altogether, vornorexant may have a favourable profile for insomnia treatment, including rapid onset of action and minimal next-day residual effects.

Does the Role of Family Assisted Cognitive Remediation Therapy Still Exists in Modern Era of Artificial Intelligence: A Randomized Case-control Study for Schizophrenia Patients from Rural Background

Background: Last decade showed promising evidences of computer based therapies, incorporating either an in-patient or home-based computer model for training the family members. The crux of all these studies focuses on the role of “family”. The compliance and perception, from a patient perspective, especially in a developing country, is still unproven. Purpose and Design: The aim of our randomized case-control study, was to analyze the impact of add-on FACT in stable patients of Schizophrenia and assess and the level of functioning and quality of life (QoL) among two groups. The primary outcome measures (PANSS and SCoRS) and secondary outcome measure (GAF and WHODAS) were compared among two groups. Material and methods: 96 patients of stable Schizophrenia, were randomized in two groups, Group A (study group, n=48) included patients, who receive add-on FACT and Group B (control group, n=48) includes the patients on our standard protocol (pharmacotherapy and brief counselling). Both the groups received single session of psycho-education with, Group A receiving an additional four training sessions. We targeted prospective memory, conversational and task vigilance, verbal learning and memory, cognitive flexibility and problem solving in our sessions. Assessments were done at baseline, 8 and 16 weeks and domains were compared. Results: There was significant improvement in outcome measures of psychopathology, level of functioning, quality of life and disability among patients of Group A. Of the cognitive domains, trend of an improvements was seen inattention/vigilance, working memory, processing speed, household responsibility and social cognition. Conclusion: The collaborative efforts of treating physician and family involvement showed significant clinical outcome. FACT holds promise in the rehabilitation for stable patients of schizophrenia. The therapy modifies family dynamics, retaining the roots of psycho-education and tailored cognitive therapy model; irreplaceable for any artificial intelligence model.

An at-home evaluation of a light intervention to mitigate sleep inertia symptoms

ObjectivesUnder laboratory settings, light exposure upon waking at night improves sleep inertia symptoms. We investigated whether a field-deployable light source would mitigate sleep inertia in a real-world setting. MethodsThirty-six participants (18 female; 26.6 years ± 6.1) completed an at-home, within-subject, randomized crossover study. Participants were awoken 45 minutes after bedtime and wore light-emitting glasses with the light either on (light condition) or off (control). A visual 5-minute psychomotor vigilance task, Karolinska sleepiness scale, alertness and mood scales, and a 3-minute auditory/verbal descending subtraction task were performed at 2, 12, 22, and 32 minutes after awakening. Participants then went back to sleep and were awoken after 45 minutes for the opposite condition. A series of mixed-effect models were performed with fixed effects of test bout, condition, test bout × condition, a random effect of the participant, and relevant covariates. ResultsParticipants rated themselves as more alert (p = .01) and energetic (p = .001) in the light condition compared to the control condition. There was no effect of condition for descending subtraction task outcomes when including all participants, but there was a significant improvement in descending subtraction task total responses in the light condition in the subset of participants waking from N3 (p = .03). There was a significant effect of condition for psychomotor vigilance task outcomes, with faster responses (p < .001) and fewer lapses (p < .001) in the control condition. ConclusionsOur findings suggest that light modestly improves self-rated alertness and energy after waking at home regardless of sleep stage, with lower aggression and improvements to working memory only after waking from N3. Contrary to laboratory studies, we did not observe improved performance on the psychomotor vigilance task. Future studies should include measures of visual acuity and comfort to assess the feasibility of interventions in real-world settings.

Repeated Transcranial Photobiomodulation with Light-Emitting Diodes Improves Psychomotor Vigilance and EEG Networks of the Human Brain.

Transcranial photobiomodulation (tPBM) has been suggested as a non-invasive neuromodulation tool. The repetitive administration of light-emitting diode (LED)-based tPBM for several weeks significantly improves human cognition. To understand the electrophysiological effects of LED-tPBM on the human brain, we investigated alterations by repeated tPBM in vigilance performance and brain networks using electroencephalography (EEG) in healthy participants. Active and sham LED-based tPBM were administered to the right forehead of young participants twice a week for four weeks. The participants performed a psychomotor vigilance task (PVT) during each tPBM/sham experiment. A 64-electrode EEG system recorded electrophysiological signals from each participant during the first and last visits in a 4-week study. Topographical maps of the EEG power enhanced by tPBM were statistically compared for the repeated tPBM effect. A new data processing framework combining the group's singular value decomposition (gSVD) with eLORETA was implemented to identify EEG brain networks. The reaction time of the PVT in the tPBM-treated group was significantly improved over four weeks compared to that in the sham group. We observed acute increases in EEG delta and alpha powers during a 10 min LED-tPBM while the participants performed the PVT task. We also found that the theta, beta, and gamma EEG powers significantly increased overall after four weeks of LED-tPBM. Combining gSVD with eLORETA enabled us to identify EEG brain networks and the corresponding network power changes by repeated 4-week tPBM. This study clearly demonstrated that a 4-week prefrontal LED-tPBM can neuromodulate several key EEG networks, implying a possible causal effect between modulated brain networks and improved psychomotor vigilance outcomes.

Exploring Strategies to Improve Performance Accuracy on Vigilance-Based Tasks

Vigilance is the ability to maintain attention on a task over time without becoming distracted. Many high-stakes fields require employees to regularly engage in vigilance tasks (e.g., TSA baggage screening). Understanding strategies to improve accuracy on such tasks can be critical in ensuring efficiency and safety. In the current work, trial-by-trial feedback and extrinsic motivators were tested as potential aids to improve accuracy on vigilance tasks. Measures of state boredom were also collected. Results provide insight that trial-by-trial feedback may be an effective tool to increase accuracy on basic vigilance tasks. Further research is needed to understand the impact of trial-by-trial feedback and extrinsic motivators on state boredom and their impact on applied tasks.

Event-Related Cerebral Hemodynamic Assessment of Vigilance: Evidence in Favor of a More Temporally Precise Analysis

Transcranial Doppler sonography (TCD) is a neuroergonomic measure used in research on vigilance tasks. The current study focused on eventrelated analysis of TCD data, a relatively novel analytical approach that has previously been used to reveal that brain activity increases briefly when an individual detects a critical, target stimulus. Although research suggests that this detection-related response is sensitive to fatigue and demand effects associated with vigilance, future use and interpretation of event-related TCD analyses is complicated by interstudy variability in the time course and magnitude of the detection-related response. One possibility is that previous methods may have been too temporally coarse (4-second averages), so the current study reanalyzed data from one previous event-related study – this time using narrower 2-second averages. Results indicated that 2-second averages provided more precise depiction of the detection-related response than 4-second averages. We recommend use of 2-second averages for future eventrelated CBFV research.

People with high self-control have increased performance and neural efficiency in temporally uncertain vigilance tasks

The vigilance decrement, the decline in behavioral adaptability seen after sustaining attention over time, has been a monumental problem in the applied sciences for the past 70 years. Trait selfcontrol is a measure of the general capability to regulate one’s own cognitive resources. In the present study, participants performed a 24-minute vigilance task that was either synchronous (temporally regular) or asynchronous (temporally irregular). We empirically investigated the effects of self-control, watch period, and event asynchrony on performance and neural resource expenditure through functional near-infrared spectroscopy (fNIRS). Here we demonstrate that trait self-control indexes an operator’s capability to prevent making false alarms. Additionally, we elaborate on the functional role of self-control in optimizing right parietal resource usage and subsequently, resilience against the vigilance decrement. Finally, we discuss theoretical and practical implications for Neuroergonomics practitioners.