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Summary: Chronic sleep restriction, common in today's 24/7 society, causes cumulative neurobehavioural impairment, but the dynamics of the build‐up and dissipation of this impairment have not been fully elucidated. We addressed this knowledge gap in a laboratory study involving two, 5‐day periods of sleep restriction to 4 hr per day, separated by a 1‐day dose–response intervention sleep opportunity. We measured sleep physiological and waking neurobehavioural responses in 70 healthy adults, each randomized to one of seven dose–response intervention sleep doses ranging from 0 to 12 hr, or a non‐sleep‐restricted control group. As anticipated, sleep physiological markers showed homeostatic dynamics throughout the study, and waking neurobehavioural impairment accumulated across the two sleep restriction periods. Unexpectedly, there was only a slight and short‐lived effect of the 1‐day dose–response intervention sleep opportunity. Whether the dose–response intervention sleep opportunity involved extension, further restriction or total deprivation of sleep, neurobehavioural functioning during the subsequent second sleep restriction period was dominated by prior sleep–wake history. Our findings revealed a profound and enduring influence of long‐term sleep–wake history as a fundamental aspect of the dynamic regulation of the neurobehavioural response to sleep loss. [ABSTRACT FROM AUTHOR]

Vigilant attention (VA) is a fundamental neurocognitive function. However, the association between habitual snoring (HS) and VA in community-based children remains unclear. Therefore, this study aimed to elucidate the association. The study included 2014 children from grades 1–6 across six elementary schools. Snoring frequency was evaluated using a questionnaire administered to parents. VA was assessed using a brief 3-min psychomotor vigilance test (PVT-B). Generalized linear models and multivariate logistic regression analysis were utilized to examine the association between snoring frequency and PVT-B performance. Impaired PVT-B performance was defined as the worst quartile of PVT-B metrics. The PVT-B performance significantly improved with advancing school grade level (p trend < 0.0001). A significant negative correlation was observed between snoring frequency and PVT-B performance. Particularly, in grade 1, HS was associated with a higher risk of impaired PVT-B performance, including response speed (mean reciprocal reaction time) (adjusted odds ratio [aOR] 2.56, 95% confidence interval [CI]: 1.20–5.50), more slowest 10% RT (aOR 3.28, 95% CI: 1.51–6.88), and more lapse500 (number of lapse of reaction time ≥ 500 ms) (aOR 3.18, 95% CI: 1.45–6.80) compared to children without snoring. Our findings show that VA rapidly improves throughout elementary school. Additionally, younger children with HS are at risk of VA deficits, emphasizing the importance of early intervention for HS. [ABSTRACT FROM AUTHOR]

BackgroundSleep loss has sometimes catastrophic effects on risky decision-making. However, it is unknown to what extent such deficits are exacerbated with increasing duration of sleep deprivation (SD) and whether sustained vigilant attention mediates this sleep deprivation-induced deficit.MethodsThe present study aimed to investigate the effect of 36 hours of SD on 37 male college students’ arousal, emotion, vigilant attention, and risky decision-making, using the Psychomotor Vigilance Test, the Game of Dice Task, and scales assessing fatigue, sleep, and emotions. ResultsCompared to baseline, SD significantly increased sleepiness, fatigue, and negative emotions, decreased positive emotions and vigilant attention, and led to a shift toward risky decision-making, and these effects often appeared 15 or 20 hours after SD. Interestingly, participants’ ability to employ positive feedback was maintained, whereas their performance to utilize negative feedback was impaired even after 8 hours of sleep deprivation. Meanwhile, vigilant attention acted as a mediator between SD and risky decision-making (z = -1.97, 95% [-6.00, -0.30]).DiscussionThese results suggest that sleep-deprived individuals are unable to use negative feedback to optimize their judgments, which may account for their poor decision-making under risk.

Individuals exhibit considerable variability in their capacity to learn and retain new information, including novel vocabulary. Prior research has established the importance of vigilance and electroencephalogram (EEG) alpha rhythm in the learning process. However, the interplay between vigilant attention, EEG alpha oscillations, and an individual's word learning ability (WLA) remains elusive. To address this knowledge gap, here we conducted two experiments with a total of 140 young and middle-aged adults who underwent resting EEG recordings prior to completing a paired-associate word learning task and a psychomotor vigilance test (PVT). The results of both experiments consistently revealed significant positive correlations between WLA and resting EEG alpha oscillations in the occipital and frontal regions. Furthermore, the association between resting EEG alpha oscillations and WLA was mediated by vigilant attention, as measured by the PVT. These findings provide compelling evidence supporting the crucial role of vigilant attention in linking EEG alpha oscillations to an individual's learning ability.

Summary: Sleep deprivation consistently decreases vigilant attention, which can lead to difficulty in performing a variety of cognitive tasks. However, sleep‐deprived individuals may be able to compensate for degraded vigilant attention by means of top‐down attentional control. We employed a novel task to measure the degree to which individuals overcome impairments in vigilant attention by using top‐down attentional control, the Flexible Attentional Control Task (FACT). The FACT is a two‐choice task that has trials with valid, invalid, and neutral cues, along with an unexpected switch in the probability of cue validity about halfway in the task. The task provides indices that isolate performance components reflecting vigilant attention and top‐down attentional control. Twelve healthy young adults completed an in‐laboratory study. After a baseline day, the subjects underwent 39 hours of total sleep deprivation (TSD), followed by a recovery day. The FACT was administered at 03:00, 11:00, and 19:00 during sleep deprivation (TSD condition) and at 11:00 and 19:00 after baseline sleep and at 11:00 after recovery sleep (rested condition). When rested, the subjects demonstrated both facilitation and interference effects on cued trials. While sleep deprived, the subjects showed vigilant attention deficits on neutral cue trials, and an impaired ability to reduce these deficits by using predictive contextual cues. Our results indicate that the FACT can dissociate vigilant attention from top‐down attentional control. Furthermore, they show that during sleep deprivation, contextual cues help individuals to compensate partially for impairments in vigilant attention, but the effectiveness of top‐down attentional control is diminished. [ABSTRACT FROM AUTHOR]

Drowsiness associated with sleep loss and circadian misalignment is a risk factor for accidents and human error. The percentage of time that the eyes are more than 80% closed (PERCLOS) is one of the most validated indices used for the passive detection of drowsiness, which is increased with sleep deprivation, after partial sleep restriction, at nighttime, and by other drowsiness manipulations during vigilance tests, simulated driving, and on-road driving. However, some cases have been reported wherein PERCLOS was not affected by drowsiness manipulations, such as in moderate drowsiness conditions, in older adults, and during aviation-related tasks. Additionally, although PERCLOS is one of the most sensitive indices for detecting drowsiness-related performance impairments during the psychomotor vigilance test or behavioral maintenance of wakefulness test, no single index is currently available as an optimal marker for detecting drowsiness during driving or other real-world situations. Based on the current published evidence, this narrative review suggests that future studies should focus on: (1) standardization to minimize differences in the definition of PERCLOS between studies; (2) extensive validation using a single device that utilizes PERCLOS-based technology; (3) development and validation of technologies that integrate PERCLOS with other behavioral and/or physiological indices, because PERCLOS alone may not be sufficiently sensitive for detecting drowsiness caused by factors other than falling asleep, such as inattention or distraction; and (4) further validation studies and field trials targeting sleep disorders and trials in real-world environments. Through such studies, PERCLOS-based technology may contribute to preventing drowsiness-related accidents and human error. [ABSTRACT FROM AUTHOR]

Study Objectives The influence of biological sex on sleep inertia symptoms is currently unknown. We investigated the role of sex differences in the subjective experience and objective cognitive manifestation of sleep inertia following nighttime awakenings. Methods Thirty-two healthy adults (16 female, 25.91 ± 5.63 years) completed a 1-week at-home study with one experimental night during which sleep was measured by polysomnography and participants were awakened during their habitual sleep time. Participants completed a psychomotor vigilance task, Karolinska Sleepiness Scale (KSS), visual analog mood scales, and a descending subtraction task (DST) prior to sleep (baseline) and at 2, 12, 22, and 32 min after awakening. A series of mixed-effects models with Bonferroni-corrected post hoc tests were used to examine the main effects of test bout and sex, and their interaction, with a random effect of participant, and order of wake-up and sleep history as covariates. Results All outcomes except for percent correct on the DST showed a significant main effect of test bout, with worse performance after waking compared to baseline (all p s < .003). Significant effects of sex (p  = .002) and sex × test bout (p  = .01; R 2M = 0.49, R 2C = 0.69) were observed for KSS, with females reporting a greater increase in sleepiness from baseline to after waking compared to males. Conclusions These results suggest that while females reported feeling sleepier than males following nighttime awakenings, their cognitive performance was comparable. Future research is needed to determine whether perceptions of sleepiness influence decision-making during the transition from sleep to wakefulness. [ABSTRACT FROM AUTHOR]

Background: Vigilant Attention (VA) is a critical cognitive function allowing to maintain our attention, particularly in redundant or intellectually unchallenging situations. Evidence has shown that, as the brain develops, VA abilities rapidly improve throughout childhood and adolescence. Dietary omega-3 polyunsaturated fats (PUFA), playing a critical role for proper brain development and maturation of cortical regions, may contribute to variations in VA abilities. Objective: The present study investigated the effect of dietary omega-3 PUFA intake (docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA)) on resting-state functional connectivity (rsFC) of a meta-analytically defined VA network in 24 neurotypical children and adolescents (7.3–17.2 years) from the Healthy Brain Network databank. Methods: Functional MRI and phenotypical information were collected from the Healthy Brain Network databank. Intake of omega-3 DHA and EPA was assessed using a food frequency questionnaire and was adjusted for total calorie intake. Out of scanner VA-related performance was assessed using the VA condition of the Adaptive Cognitive Evaluation tool. Results: Overall, reported intake of omega-3 PUFA was not significantly associated with VA-related performance. Furthermore, energy-adjusted omega-3 intake was not significantly correlated with rsFC within the VA network. A complementary whole-brain analysis revealed that energy-adjusted omega-3 intake was correlated with decreased rsFC between parieto-occipital brain regions. Conclusion: The present study was not able to detect a relationship between dietary omega-3 and rsFC or VA performance. [ABSTRACT FROM AUTHOR]

Physical exertion mimicking firefighting conditions mitigated cognitive deficits from sleep loss, but benefits were limited to executive function reaction time (RT). Vigilant attention and executive function accuracy remained impaired. We conclude physical exertion is insufficient to eliminate cognitive deficits from sleep loss, and additional countermeasures are needed to ensure occupational safety. Objective: The aim of the study is to investigate effects of physical exertion on cognitive deficits from sleep loss under conditions that mimic a firefighting scenario. Methods: Twenty-four male participants completed a crossover study design with 3 conditions: total sleep deprivation, sleep disruption (three 60-minute awakenings), and rested control. Participants then completed 50 minutes of a physical exertion task involving treadmill exercise in a heated room while wearing firefighter protective clothing. Vigilant attention and task-switching performance were assessed pre– and post–sleep manipulation and pre– and post–physical exertion. Vigilant attention was also assessed mid–physical exertion. Results: Total sleep deprivation and sleep disruption increased attentional lapses and task-switching RT. Total sleep deprivation additionally reduced task-switching accuracy. Performance after physical exertion improved only for task-switching RT after total sleep deprivation. Conclusions: Physical exertion selectively mitigated task-switching RT deficits from the most severe sleep loss condition, total sleep deprivation. [ABSTRACT FROM AUTHOR]

Tianxin Mao,1,2 David Dinges,3 Yao Deng,1,2 Ke Zhao,2 Zijing Yang,2,4 Hui Lei,2 Zhuo Fang,2 Fan Nils Yang,2 Olga Galli,3 Namni Goel,5 Mathias Basner,3 Hengyi Rao1– 3 1Key Laboratory of Applied Brain and Cognitive Sciences, School of Business and Management, Shanghai International Studies University, Shanghai, People’s Republic of China; 2Center for Functional Neuroimaging, Department of Neurology, University of Pennsylvania, Philadelphia, PA, USA; 3Division of Sleep and Chronobiology, Department of Psychiatry, University of Pennsylvania, Philadelphia, PA, USA; 4School of Medicine, Shanghai Jiaotong University, Shanghai, People’s Republic of China; 5Biological Rhythms Research Laboratory, Department of Psychiatry and Behavioral Sciences, Rush University Medical Center, Chicago, IL, USACorrespondence: Hengyi RaoCenter for Functional Neuroimaging & Department of Neurology, University of Pennsylvania Perelman School of Medicine, Room D502, Richards Medical Research Building, 3700 Hamilton Walk, Philadelphia, PA, 19104-4202, USATel +1 215-746-2470Email hengyi@pennmedicine.upenn.eduPurpose: Sleep loss impairs a range of neurobehavioral functions, particularly vigilant attention and arousal. However, the detrimental effects of sleep deprivation on inhibition control and its relationship to vigilant attention impairments remain unclear. This study examined the extent to which vigilant attention deficits contribute to inhibition control performance after one night of total sleep deprivation (TSD) and two nights of partial sleep restriction (PSR).Participants and Methods: We analyzed data from N = 49 participants in a one-night of TSD experiment, N=16 participants in a control experiment without sleep loss, and N = 16 participants in a two-nights of PSR experiment (time in bed, TIB = 6 h for each night). Throughout waking periods in each condition, participants completed the psychomotor vigilance test (PVT), which measures vigilant attention, and the Go/No-Go task, which measures inhibition control.Results: After TSD and PSR, participants displayed significantly slower reaction times (RT) and more lapses in PVT performance, as well as slower Go RT and more errors of omission during the Go/No-Go task. PVT deficits accounted for 18.0% of the change in Go RT and 12.4% of the change in errors of omission in the TSD study, and 23.7% of the change in Go RT and 20.3% of the change in errors of omission in the PSR study.Conclusion: Both TSD and PSR impaired inhibition control during the Go/No-Go task, which can be partly accounted for by vigilant attention deficits during the PVT. These findings support the key role of vigilant attention in maintaining overall neurobehavioral function after sleep loss.Keywords: total sleep deprivation, partial sleep restriction, vigilant attention, inhibition control

Emotion is characterized by dimensions of affective valence and arousal, either or both of which may be altered by sleep loss, thereby contributing to impaired regulatory functioning. Controlled laboratory studies of total sleep deprivation (TSD) generally show alterations in physiological arousal and affective state, but the relationship of affect and emotion with physiological arousal during TSD has not been well characterized. Established methods for examining physiological arousal include electrodermal activity (EDA) measures such as non-specific skin conductance responses (NSSCR) and skin conductance level (SCL). These measures are robust physiological markers of sympathetic arousal and have been linked to changes in experienced emotion. To explore the link between physiological arousal and affect during sleep deprivation, we investigated individuals' EDA under TSD and its relationship to self-reported affect. We also investigated the relationship of EDA to two other measures known to be particularly sensitive to the arousal-decreasing effects of TSD, i.e., self-reported sleepiness and performance on a vigilant attention task. Data were drawn from three previously published laboratory experiments where participants were randomly assigned to either well-rested control (WRC) or 38 h of TSD. In this data set, comprising one of the largest samples ever used in an investigation of TSD and EDA (N = 193 with 74 WRC and 119 TSD), we found the expected impairing effects of TSD on self-reported affect and sleepiness and on vigilant attention. Furthermore, we found that NSSCR, but not SCL, were sensitive to TSD, with significant systematic inter-individual differences. Across individuals, the change in frequency of NSSCR during TSD was not predictive of the effect of TSD on affect, sleepiness, or vigilant attention, nor was it related to these outcomes during the rested baseline. Our findings indicate that while physiological arousal, as measured by EDA, may be useful for assessing TSD-related changes in non-specific arousal at the group level, it is not associated with individuals' self-reported affect at rest nor their change in affect during TSD. This suggests that an essential aspect of the relationship between physiological arousal and self-reported affect is not well captured by EDA as measured by NSSCR. [ABSTRACT FROM AUTHOR]

Emotion is characterized by dimensions of affective valence and arousal, either or both of which may be altered by sleep loss, thereby contributing to impaired regulatory functioning. Controlled laboratory studies of total sleep deprivation (TSD) generally show alterations in physiological arousal and affective state, but the relationship of affect and emotion with physiological arousal during TSD has not been well characterized. Established methods for examining physiological arousal include electrodermal activity (EDA) measures such as non-specific skin conductance responses (NSSCR) and skin conductance level (SCL). These measures are robust physiological markers of sympathetic arousal and have been linked to changes in experienced emotion. To explore the link between physiological arousal and affect during sleep deprivation, we investigated individuals’ EDA under TSD and its relationship to self-reported affect. We also investigated the relationship of EDA to two other measures known to be particularly sensitive to the arousal-decreasing effects of TSD, i.e., self-reported sleepiness and performance on a vigilant attention task. Data were drawn from three previously published laboratory experiments where participants were randomly assigned to either well-rested control (WRC) or 38 h of TSD. In this data set, comprising one of the largest samples ever used in an investigation of TSD and EDA (N = 193 with 74 WRC and 119 TSD), we found the expected impairing effects of TSD on self-reported affect and sleepiness and on vigilant attention. Furthermore, we found that NSSCR, but not SCL, were sensitive to TSD, with significant systematic inter-individual differences. Across individuals, the change in frequency of NSSCR during TSD was not predictive of the effect of TSD on affect, sleepiness, or vigilant attention, nor was it related to these outcomes during the rested baseline. Our findings indicate that while physiological arousal, as measured by EDA, may be useful for assessing TSD-related changes in non-specific arousal at the group level, it is not associated with individuals’ self-reported affect at rest nor their change in affect during TSD. This suggests that an essential aspect of the relationship between physiological arousal and self-reported affect is not well captured by EDA as measured by NSSCR.

Humans generally display vigilance decrement during sustained cognitive workloads, while visual and auditory stimuli have been shown to elicit arousal, which influences the level of user vigilance. This study explored the effects of hue and background music pitch on user vigilance. Thirty-five participants performed a 10-min Psychomotor Vigilance Test with background music playing. Three hue conditions (red, green, and yellow) and two background music pitch conditions (high and low pitch) were randomly combined in each task, and the reaction time (RT) and number of lapses under different conditions were measured. We found that the overall vigilance performance was the best (shortest RT and fewest lapses) and the worst, and the vigilance decrement was the fastest and the slowest, respectively, with the red and the yellow signal. Moreover, the overall vigilance performance was best with low-pitched background music, while the pitch did not affect vigilance decrement. These findings can be used in situations with repeated color-signal stimulation and music playing (e.g., driving, signal monitoring, and physical training) to improve users' vigilance performance. • Signal hue has an effect on overall vigilance performance, with red signals eliciting the best performance. • Background music pitch has an effect on overall vigilance performance, with low-pitched music eliciting the best performance. • Red signals exacerbate the vigilance decrement while yellow signals mitigate it. [ABSTRACT FROM AUTHOR]

Neurobehavioral task performance is modulated by the circadian and homeostatic processes of sleep/wake regulation. Biomathematical modeling of the temporal dynamics of these processes and their interaction allows for prospective prediction of performance impairment in shift-workers and provides a basis for fatigue risk management in 24/7 operations. It has been reported, however, that the impact of the circadian rhythm—and in particular its timing—is inherently task-dependent, which would have profound implications for our understanding of the temporal dynamics of neurobehavioral functioning and the accuracy of biomathematical model predictions. We investigated this issue in a laboratory study designed to unambiguously dissociate the influences of the circadian and homeostatic processes on neurobehavioral performance, as measured during a constant routine protocol preceded by three days on either a simulated night shift or a simulated day shift schedule. Neurobehavioral functions were measured every 2 h using three functionally distinct assays: a digit symbol substitution test, a psychomotor vigilance test, and the Karolinska Sleepiness Scale. After dissociating the circadian and homeostatic influences and accounting for inter-individual variability, peak circadian performance occurred in the late biological afternoon (in the "wake maintenance zone") for all three neurobehavioral assays. Our results are incongruent with the idea of inherent task-dependent differences in the endogenous circadian impact on performance. Rather, our results suggest that neurobehavioral functions are under top-down circadian control, consistent with the way they are accounted for in extant biomathematical models. [ABSTRACT FROM AUTHOR]

Background: Sleep deprivation can markedly influence vigilant attention that is essential to complex cognitive processes. The hypothalamus plays a critical role in arousal and attention regulation. However, the functional involvement of the hypothalamus in attentional impairments after total sleep deprivation (TSD) remains unclear. The purpose of this study is to investigate the alterations in hypothalamic functional connectivity and its association with the attentional performance following TSD. Methods: Thirty healthy adult males were recruited in the study. Participants underwent two resting-state functional magnetic resonance imaging (rs-fMRI) scans, once in rested wakefulness (RW) and once after 36 h of TSD. Seed-based functional connectivity analysis was performed using rs-fMRI for the left and right hypothalamus. Vigilant attention was measured using a psychomotor vigilance test (PVT). Furthermore, Pearson correlation analysis was conducted to investigate the relationship between altered hypothalamic functional connectivity and PVT performance after TSD. Results: After TSD, enhanced functional connectivity was observed between the left hypothalamus and bilateral thalamus, bilateral anterior cingulate cortex, right amygdala, and right insula, while reduced functional connectivity was observed between the left hypothalamus and bilateral middle frontal gyrus (AlphaSim corrected, P < 0.01). However, significant correlation between altered hypothalamic functional connectivity and PVT performance was not observed after Bonferroni correction (P > 0.05). Conclusion: Our results suggest that TSD can lead to disrupted hypothalamic circuits, which may provide new insight into neural mechanisms of attention impairments following sleep deprivation. [ABSTRACT FROM AUTHOR]

• Sleep deprivation leads to disrupted small-world networks. • Sleep loss induces enhanced clustering coefficient while reduced global efficiency. • Disrupted small-world networks link to attention decline after sleep deprivation. Sleep deprivation critically affects vigilant attention. Previous neuroimaging studies have revealed altered inter-regional functional connectivity after sleep deprivation, which may disrupt topological properties of brain functional networks. However, little is known about alterations in the topology of intrinsic connectivity and its involvement in attention performance after sleep deprivation. In the current study, we investigated the topological properties of brain networks derived from resting-state functional magnetic resonance imaging of 26 healthy men in rested wakefulness (RW) state and after 36 h of total sleep deprivation (TSD). In the predefined sparsity threshold range, both global and nodal network properties were evaluated based on graph theory analysis. Vigilant attention was assessed using the psychomotor vigilance test (PVT) before and after TSD. Furthermore, Pearson's correlation analyses were conducted to explore the association between altered network properties and changed PVT performance after TSD. At the global level, the brain functional networks in the TSD state showed a significantly lower small-world coefficient than RW, with decreased global efficiency. At the nodal level, the altered regions were selectively distributed in frontoparietal networks, sensorimotor networks, temporal regions, and salience networks. More specifically, the altered clustering coefficient in the posterior superior temporal sulcus (pSTS) and insula, and altered local efficiency in pSTS were further associated with PVT performance after TSD. Our results suggest that the topological properties of brain functional networks are disrupted, and aberrant topology of temporal networks and salience networks may act as neural signatures underlying the vigilant attention impairments after TSD. [ABSTRACT FROM AUTHOR]

Background: Sleep deprivation can markedly influence vigilant attention that is essential to complex cognitive processes. The hypothalamus plays a critical role in arousal and attention regulation. However, the functional involvement of the hypothalamus in attentional impairments after total sleep deprivation (TSD) remains unclear. The purpose of this study is to investigate the alterations in hypothalamic functional connectivity and its association with the attentional performance following TSD.Methods: Thirty healthy adult males were recruited in the study. Participants underwent two resting-state functional magnetic resonance imaging (rs-fMRI) scans, once in rested wakefulness (RW) and once after 36 h of TSD. Seed-based functional connectivity analysis was performed using rs-fMRI for the left and right hypothalamus. Vigilant attention was measured using a psychomotor vigilance test (PVT). Furthermore, Pearson correlation analysis was conducted to investigate the relationship between altered hypothalamic functional connectivity and PVT performance after TSD.Results: After TSD, enhanced functional connectivity was observed between the left hypothalamus and bilateral thalamus, bilateral anterior cingulate cortex, right amygdala, and right insula, while reduced functional connectivity was observed between the left hypothalamus and bilateral middle frontal gyrus (AlphaSim corrected, P < 0.01). However, significant correlation between altered hypothalamic functional connectivity and PVT performance was not observed after Bonferroni correction (P > 0.05).Conclusion: Our results suggest that TSD can lead to disrupted hypothalamic circuits, which may provide new insight into neural mechanisms of attention impairments following sleep deprivation.

Background: Sleep deprivation can robustly affect vigilant attention. The insula is a key hub of the salience network that mediates shifting attention between endogenous and exogenous states. However, little is known regarding the involvement of insular functional connectivity in impaired vigilant attention after total sleep deprivation (TSD). The purpose of this study is to explore the alterations in insular functional connectivity and its association with vigilant attention performance following TSD.Methods: Twenty-six adult men were enrolled in the study. Participants underwent two counterbalanced resting-state functional magnetic resonance imaging (rs-fMRI) scans, once in rested wakefulness (RW) and once after 36 h of TSD. Seed-based functional connectivity analysis was performed using rs-fMRI data for the left and right insula. The vigilant attention was measured using a psychomotor vigilance test (PVT). Furthermore, Pearson correlation analysis was conducted to investigate the relationship between altered insular functional connectivity and PVT performance.Results: Compared to RW, enhanced functional connectivity was observed between the insula and prefrontal cortex and anterior cingulate cortex, while reduced functional connectivity was observed between the insula and temporal, parietal, and occipital regions following TSD. Moreover, altered insular functional connectivity with the prefrontal cortex, ie superior frontal gyrus and middle frontal gyrus, and inferior temporal gyrus was correlated with PVT performance after TSD.Conclusion: Our results suggest that insular coupling with the prefrontal cortex and inferior temporal gyrus may act as neural indicators for vigilant attention impairment, which further reveals the critical role of the salience network in cognitive decline following TSD. [ABSTRACT FROM AUTHOR]

Total sleep deprivation (TSD) is known to impair sustained attention. However, previously reported effects of TSD on response inhibition are mixed. We administered a "stop-signal" variation of the psychomotor vigilance test, which included 25% of trials requiring withholding of a response to assess response inhibition alongside sustained attention. Participants completed the task at baseline and after 34.5 h of wakefulness. Accuracy was not reduced during TSD. However, response times were significantly slower. A speed/accuracy trade-off allowed participants to effectively withhold responses on inhibition trials and conferred resilience of inhibitory control during TSD under conditions of relatively low time pressure. [ABSTRACT FROM AUTHOR]

Besides degrading vigilant attention, total sleep deprivation (TSD) impairs reversal learning performance and blunts affective reactions to feedback. Whether these effects are downstream consequences of information acquisition failures from degraded vigilant attention, or distinct from degraded vigilant attention, is unclear. In well-rested individuals we simulated information acquisition failures by masking a portion of trial information in a go/no-go reversal learning task with four conditions: stimulus masking, feedback masking, alternating stimulus/feedback masking, and no-masking control. No condition reproduced the previously documented pattern of TSD effects, suggesting that information acquisition failures cannot fully account for impaired reversal learning and blunted affective reactions during TSD. [ABSTRACT FROM AUTHOR]

Total sleep deprivation (TSD) impairs attention as well as higher-order cognitive processes. Because attention is a core component of many tasks, it may fully mediate the effect of sleep deprivation on higher-order processes. We examined this possibility using the Psychomotor Vigilance Task as a measure of attention and the UNRAVEL task as a measure of placekeeping, a higher-order process that involves memory operations and supports performance in a wide range of complex tasks. A large sample of participants (N = 138 contributing data) performed the Psychomotor Vigilance Task and UNRAVEL under rested or sleep-deprived conditions. TSD impaired placekeeping generally and memory maintenance processes specifically, above and beyond the effect of participants' attentional state. The results suggest that TSD may impair a range of higher-order cognitive processes directly, not just fundamental processes such as attention, and that interventions that benefit attention may have limited scope. [ABSTRACT FROM AUTHOR]

We aimed at assessing whether a head‐mounted light therapy device, enriched in blue wavelengths, suppresses melatonin secretion and improves vigilant attention in the late evening hours. We also assessed whether using such light device is associated with discomfort and physiological stress. Seventeen healthy young participants (eight females) participated in a counterbalanced within‐subject design during which they were exposed for 2 hr before habitual sleep time to a blue‐enriched light (1500 lx) or to a lower intensity red‐light (150 lx) control condition, using a new‐generation light emitting diode (LED) head‐mounted device. Compared to the red light control condition, blue‐enriched light significantly reduced melatonin secretion and reaction times during a psychomotor vigilance task while no significant differences were detected in discomfort and cortisol levels. These results suggest that, compared to a control condition, blue‐enriched light, delivered by a new‐generation head‐mounted device, elicits typical non‐visual responses to light without detectable discomfort and physiological stress. They suggest that such devices might constitute an effective alternative to standard light boxes. [ABSTRACT FROM AUTHOR]

• The study is the first to reveal significant positive correlations between resting EEG alpha oscillations and novel word learning ability. • The study is the first to discover the mediating role of vigilant attention in linking EEG alpha oscillations to an individual's learning ability, which advances the understanding of the underlying mechanism between spontaneous alpha-band activities and multiple learning abilities. • The above findings were validated across two independent experiments with a total of 140 participants, which has not only enriched the representational meaning of alpha rhythm, but also provided potential neurocognitive markers for the early detection of the individuals with word learning difficulties. Individuals exhibit considerable variability in their capacity to learn and retain new information, including novel vocabulary. Prior research has established the importance of vigilance and electroencephalogram (EEG) alpha rhythm in the learning process. However, the interplay between vigilant attention, EEG alpha oscillations, and an individual's word learning ability (WLA) remains elusive. To address this knowledge gap, here we conducted two experiments with a total of 140 young and middle-aged adults who underwent resting EEG recordings prior to completing a paired-associate word learning task and a psychomotor vigilance test (PVT). The results of both experiments consistently revealed significant positive correlations between WLA and resting EEG alpha oscillations in the occipital and frontal regions. Furthermore, the association between resting EEG alpha oscillations and WLA was mediated by vigilant attention, as measured by the PVT. These findings provide compelling evidence supporting the crucial role of vigilant attention in linking EEG alpha oscillations to an individual's learning ability. [ABSTRACT FROM AUTHOR]

Sleep deprivation impairs performance on cognitive tasks, but it is unclear which cognitive processes it degrades. We administered a semantic matching task with variable stimulus onset asynchrony (SOA) and both speeded and self-paced trial blocks. The task was administered at the baseline and 24 hours later after 30.8 hours of total sleep deprivation (TSD) or matching well-rested control. After sleep deprivation, the 20% slowest response times (RTs) were significantly increased. However, the semantic encoding time component of the RTs remained at baseline level. Thus, the performance impairment induced by sleep deprivation on this task occurred in cognitive processes downstream of semantic encoding. [ABSTRACT FROM AUTHOR]

Objective Epidemiological and laboratory-based driving simulator studies have shown the detrimental impact of moderate, legal levels of alcohol consumption on driving performance in sleepy drivers. As less is known about the time course of decaying alcohol alongside performance impairment, our study examined impairment and recovery of performance alongside decaying levels of alcohol, with and without sleep restriction. Methods Sixteen healthy young males (18-27 years) underwent 4 counterbalanced conditions: Baseline, Alcohol (breath alcohol concentration [BrAC] < 0.05%), Sleep Restriction (5 hr time in bed), and Combined. Participants consumed alcohol (or control drink) ~4.5 hr post wake (12:30 p.m.). To test on the descending limb of alcohol, attention and vigilance test batteries commenced 1 hr after consumption and were completed every 30 min for 2 hr (1:30 p.m.-3:30 p.m.). Results The Combined condition impaired subjective and objective sleepiness. Here, performance deficits peaked 90 min after alcohol consumption or 30 min after the BrAC peak. Performance did not return to baseline levels until 2.5 hr following consumption, despite receiving rest breaks in between testing. Conclusions These findings suggest that (a) falling BrACs are an inadequate guide for performance/safety and (b) rest breaks without sleep are not a safety measure for mitigating performance impairment when consuming alcohol following restricted sleep. [ABSTRACT FROM AUTHOR]

Study Objectives: The influence of biological sex on sleep inertia symptoms is currently unknown. We investigated the role of sex differences in the subjective experience and objective cognitive manifestation of sleep inertia following nighttime awakenings., Methods: Thirty-two healthy adults (16 female, 25.91 ± 5.63 years) completed a 1-week at-home study with one experimental night during which sleep was measured by polysomnography and participants were awakened during their habitual sleep time. Participants completed a psychomotor vigilance task, Karolinska Sleepiness Scale (KSS), visual analog mood scales, and a descending subtraction task (DST) prior to sleep (baseline) and at 2, 12, 22, and 32 min after awakening. A series of mixed-effects models with Bonferroni-corrected post hoc tests were used to examine the main effects of test bout and sex, and their interaction, with a random effect of participant, and order of wake-up and sleep history as covariates., Results: All outcomes except for percent correct on the DST showed a significant main effect of test bout, with worse performance after waking compared to baseline (all p s < .003). Significant effects of sex ( p  = .002) and sex × test bout ( p  = .01; R 2 M  = 0.49, R 2 C  = 0.69) were observed for KSS, with females reporting a greater increase in sleepiness from baseline to after waking compared to males., Conclusions: These results suggest that while females reported feeling sleepier than males following nighttime awakenings, their cognitive performance was comparable. Future research is needed to determine whether perceptions of sleepiness influence decision-making during the transition from sleep to wakefulness., (Published by Oxford University Press on behalf of Sleep Research Society 2022.)

Only a few studies addressed age-related changes from childhood to adolescence in sleep patterns, sleepiness, and attention. Vigilant attention plays a key role in cognitive performance. While its nature and course have been investigated broadly among adults, only limited research has been conducted on its development between childhood and adolescence. The main aim of the current study was to replicate previous findings about the effects of sleep loss on age-related changes in vigilance attention performance and sleepiness in a natural setting. A total of 104 children and adolescents (46 children aged 6-9 and 58 adolescents aged 13-19) wore an actigraph for a continuous five to seven nights, including weekdays and weekends. Subjective sleepiness (Karolinska Sleepiness Scale) and a Psychomotor Vigilance Test (PVT-B) were measured on two school days and one non-school day. Findings showed that PVT-B performance differed by age group, with adolescents outperforming children in PVT-B measures in spite of their elevated subjective sleepiness. Adolescents demonstrated less sleep time and increased sleepiness. Although PVT-B performance was better among adolescents, a within-subject analysis revealed that adolescents performed better on PVT measures on weekends than on weekdays. The results are discussed in relation to the synaptic elimination model.

Astronauts are required to maintain optimal neurobehavioral functioning despite chronic exposure to the stressors and challenges of spaceflight. Sleep of adequate quality and duration is fundamental to neurobehavioral functioning, however astronauts commonly experience short sleep durations in spaceflight (<6 h). As humans embark on long-duration space exploration missions, there is an outstanding need to identify the consequences of sleep deficiency in spaceflight on neurobehavioral functions. Therefore, we conducted a longitudinal study that examined the sleep-wake behaviors, neurobehavioral functions, and ratings of stress and workload of N = 24 astronauts before, during, and after 6-month missions aboard the International Space Station (ISS). The computerized, Reaction SelfTest (RST), gathered astronaut report of sleep-wake behaviors, stress, workload, and somatic behavioral states; the RST also objectively assessed vigilant attention (i.e. Psychomotor Vigilance Test-Brief). Data collection began 180 days before launch, continued every 4 days in-flight aboard the ISS, and up to 90 days post-landing, which produced N = 2,856 RSTs. Consistent with previous ISS studies, astronauts reported sleeping ~6.5 h in-flight. The adverse consequences of short sleep were observed across neurobehavioral functions, where sleep durations <6 h were associated with significant reductions in psychomotor response speed, elevated stress, and higher workload. Sleep durations <5 h were associated with elevated negative somatic behavioral states. Furthermore, longer sleep durations had beneficial effects on astronaut neurobehavioral functions. Taken together, our findings highlight the importance of sleep for the maintenance of neurobehavioral functioning and as with humans on Earth, astronauts would likely benefit from interventions that promote sleep duration and quality., (© The Author(s) 2022. Published by Oxford University Press on behalf of Sleep Research Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The development of Vigilant Attention (VA), the ability to focus and maintain our attention to repetitive and cognitively unchallenging tasks over time, has been investigated for more than a decade. The development of this critical executive function across the lifespan has been characterised by a rapid improvement in VA performance throughout childhood and adolescence, a steady improvement in adulthood and a slow decline in older adulthood. However, the development of the neural correlates of VA in children and adolescents remains poorly understood. Using a cross-sectional design, the present study used a meta-analytically defined VA network in children and adolescents to explore the developmental trend of the resting-state functional connectivity (rsFC) within the VA network across two independent cohorts. The results showed a linear and non-linear decrease of rsFC between the left and right VA brain regions across age. However, the results could not be reproduced in the replication cohort, potentially due to a smaller sample size. Based on previous findings from behavioural studies, the present findings suggest that changes in rsFC may underlie a developmental shift in cognitive strategies in neurotypical children and adolescents. [ABSTRACT FROM AUTHOR]

Sleep deprivation can markedly influence vigilant attention. The nucleus basalis of Meynert (NBM), the main source of cholinergic projections to the cortex, plays an important role in wakefulness maintenance and attention control. However, the involvement of NBM in attentional impairments after total sleep deprivation (TSD) has yet to be established. The purpose of this study is to investigate the alterations in NBM functional connectivity and its association with the attentional performance following TSD. Thirty healthy adult males were recruited in the study. Participants underwent two resting-state functional magnetic resonance imaging (rs-fMRI) scans, once in rested wakefulness (RW) and once after 36 h of TSD. Seed-based functional connectivity analysis was performed using rs-fMRI data for the left and right NBM. The vigilant attention was measured using a psychomotor vigilance test (PVT). Furthermore, Pearson correlation analysis was conducted to investigate the relationship between altered NBM functional connectivity and changed PVT performance after TSD. Compared to RW, enhanced functional connectivity was observed between right NBM and bilateral thalamus and cingulate cortex, while reduced functional connectivity was observed between left NBM and right superior parietal lobule following TSD. Moreover, altered NBM functional connectivity with the left anterior cingulate cortex was negatively correlated with PVT performance after TSD. Our results suggest that the disrupted NBM-related cholinergic circuit highlights an important role in attentional performance after TSD. The enhanced NBM functional connectivity with the anterior cingulate cortex may act as neural signatures for attentional deficits induced by sleep deprivation. [ABSTRACT FROM AUTHOR]

Sleeping for a short period (i.e. napping) may help mitigate impairments in cognitive processing caused by sleep deprivation, but there is limited research on effects of brief naps in particular. Here, we tested the effect of a brief nap opportunity (30- or 60-min) during a period of sleep deprivation on two cognitive processes with broad scope, placekeeping and vigilant attention. In the evening, participants (N = 280) completed a placekeeping task (UNRAVEL) and a vigilant attention task (Psychomotor Vigilance Task [PVT]) and were randomly assigned to either stay awake overnight or sleep at home. Sleep-deprived participants were randomly assigned to receive either no nap opportunity, a 30-min opportunity, or a 60-min opportunity. Participants who napped were set up with polysomnography. The next morning, sleep participants returned, and all participants completed UNRAVEL and the PVT. Sleep deprivation impaired performance on both tasks, but nap opportunity did not reduce the impairment, suggesting that naps longer than those tested may be necessary to cause group differences. However, in participants who napped, more time spent in slow-wave sleep (SWS) was associated with reduced performance deficits on both tasks, effects we interpret in terms of the role of SWS in alleviating sleep pressure and facilitating memory consolidation., (© Sleep Research Society 2021. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Vigilant Attention (VA), defined as the ability to maintain attention to cognitively unchallenging activities over a prolonged period of time, is critical to support higher cognitive functions and many behaviours in our everyday life. Evidence has shown that VA rapidly improves throughout childhood and adolescence until young adulthood and tends to decline in older adulthood. Although neuroimaging studies have extensively investigated this cognitive function in adults, the neural correlates of VA in neurotypical children and adolescents remain unclear. The current meta-analysis reviewed and examined functional neuroimaging studies in paediatric populations that used behavioural tasks involving VA. The selected studies (N = 25) were analyzed using the activation likelihood estimation method. Findings showed convergence of activation in mainly right-lateralized brain areas, including dorsomedial frontal cortex and parieto-temporal areas, and are consistent with previous literature on the neural correlates of VA. Results are discussed in terms of their functional and developmental implications for VA in children and adolescents., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interests., (Crown Copyright © 2020. Published by Elsevier Ltd. All rights reserved.)

Objective: Impaired attentional processes have been linked with poor outcomes after stroke, but their radiographical correlates have been infrequently studied. Our objective was to assess the relationship between stroke location and vigilant attention., Methods: A total of 39 patients presenting within 2 weeks of a minor stroke were prospectively recruited. Vigilant attention was assessed using the psychomotor vigilance task (PVT), and neuroimaging was used to assess stroke location, white matter hyperintensity (WMH) burden, and ischemic stroke involvement within lateral cholinergic projections. Correlational analyses and linear regression models tested the association between PVT performance and our neuroimaging parameters of interest. Subtractions of lesion overlays were used to identify brain regions of acute stroke patients who performed most poorly on the PVT., Results: Subcortical stroke location was a predictor of PVT performance in this cohort of acute stroke patients. Patients who performed most poorly on the PVT had lesions in the corona radiata, internal capsule, globus pallidus, and thalamus. Global WMH burden and cerebrovascular disease in lateral cholinergic pathways were not significant predictors of PVT performance., Interpretation: Subcortical stroke location was associated with impaired vigilant attention. The poorest PVT performers had stroke lesions involving the corona radiata, internal capsule, globus pallidus, and thalamus, suggesting that vigilance depends on the integrity of subcortical structures and their connections with cortical brain regions.

Study Objectives: Examine the use of spectral heart rate variability (HRV) metrics in measuring sleepiness under chronic partial sleep restriction, and identify underlying relationships between HRV, Karolinska Sleepiness Scale ratings (KSS), and performance on the Psychomotor Vigilance Task (PVT)., Design: Controlled laboratory study., Setting: Experimental laboratory of the Brain Work Research Centre of the Finnish Institute of Occupational Health, Helsinki, Finland., Participants: Twenty-three healthy young males (mean age ± SD = 23.77 ± 2.29)., Interventions: A sleep restriction group (N = 15) was subjected to chronic partial sleep restriction with 4 h sleep for 5 nights. A control group (N = 8) had 8 h sleep on all nights., Measurements and Results: Based on a search over all HRV frequency bands in the range [0.00, 0.40] Hz, the band [0.01, 0.08] Hz showed the highest correlation for HRV-PVT (0.60, 95% confidence interval [0.49, 0.69]) and HRV-KSS (0.33, 95% confidence interval [0.16, 0.46]) for the sleep restriction group; no correlation was found for the control group. We studied the fraction of variance in PVT explained by HRV and a 3-component alertness model, containing circadian and homeostatic processes coupled with sleep inertia, respectively. HRV alone explained 33% of PVT variance., Conclusions: The findings suggest that HRV spectral power reflects vigilant attention in subjects exposed to partial chronic sleep restriction., Citation: Henelius A, Sallinen M, Huotilainen M, Müller K, Virkkala J, Puolamäki K. Heart rate variability for evaluating vigilant attention in partial chronic sleep restriction.