Biomathematical modeling of fatigue due to sleep inertia.

Biomathematical models of fatigue capture the physiology of sleep/wake regulation and circadian rhythmicity to predict changes in neurobehavioral functioning over time. We used a biomathematical model of fatigue linked to the adenosinergic neuromodulator/receptor system in the brain as a framework to predict sleep inertia, that is, the transient neurobehavioral impairment experienced immediately after awakening. Based on evidence of an adenosinergic basis for sleep inertia, we expanded the biomathematical model with novel differential equations to predict the propensity for sleep inertia during sleep and its manifestation after awakening.

Effects of total sleep deprivation on components of top-down attentional control using a flexible attentional control task.

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).

Shift work and overtime across a career in law enforcement: a 15-year study.

Purpose –: To characterize changes in work hours across a career in law enforcement.

Design/methodology/approach –: = 113 police officers enrolled in the BCOPS cohort were studied. The police officers started their careers in law enforcement between 1994 and 2001 at a mid-sized, unionized police department in northwestern New York and continued to work at this police department for at least 15 years.

Fatigue risk management based on self-reported fatigue: Expanding a biomathematical model of fatigue-related performance deficits to also predict subjective sleepiness.

Biomathematical models of fatigue can be used to predict neurobehavioral deficits during sleep/wake or work/rest schedules. Current models make predictions for objective performance deficits and/or subjective sleepiness, but known differences in the temporal dynamics of objective versus subjective outcomes have not been addressed. We expanded a biomathematical model of fatigue previously developed to predict objective performance deficits as measured on the Psychomotor Vigilance Test (PVT) to also predict subjective sleepiness as self-reported on the Karolinska Sleepiness Scale (KSS).

Noise as a sleep aid: A systematic review.

White noise is purported to mask disruptive noises in the bedroom environment and be a non-pharmacological approach for promoting sleep and improving sleep quality. We conducted a systematic review of all studies examining the relationships between continuous white noise or similar broadband noise and sleep (PROSPERO 2020: CRD42020148736). Animal studies and studies using intermittent white noise to disrupt sleep or enhance slow wave activity were excluded.

Predictive and proactive fatigue risk management approaches in commercial aviation.

In commercial aviation, sharing best practices of fatigue risk management (FRM) is important for the industry, its employees, and the community. Chronobiologists and sleep scientists have elucidated the impact of the biological clock and sleep/wake schedules on fatigue and captured their contributions in biomathematical models. The application of these models and other aspects of FRM requires expertise to which not all operators have access.

Generalizability of a biomathematical model of fatigue's sleep predictions.

: Biomathematical models of fatigue (BMMF) predict fatigue during a work-rest schedule on the basis of sleep-wake histories. In the absence of actual sleep-wake histories, sleep-wake histories are predicted directly from work-rest schedules. The predicted sleep-wake histories are then used to predict fatigue.

Sleep-wake behaviors exhibited by shift workers in normal operations and predicted by a biomathematical model of fatigue.

Study Objectives: To compare rail workers' actual sleep-wake behaviors in normal operations to those predicted by a biomathematical model of fatigue (BMMF). To determine whether there are group-level residual sources of error in sleep predictions that could be modeled to improve group-level sleep predictions.

Methods: The sleep-wake behaviors of 354 rail workers were examined during 1,722 breaks that were 8-24 h in duration.

Psychomotor Vigilance Impairment During Total Sleep Deprivation Is Exacerbated in Sleep-Onset Insomnia.

Purpose: Individuals with primary insomnia frequently report cognitive impairment as a next-day consequence of disrupted sleep. Studies attempting to quantify daytime impairment objectively in individuals with insomnia have yielded mixed results, with evidence suggesting impairments in aspects of executive functioning but not psychomotor vigilance. It has been suggested that persons with insomnia may have latent performance deficits for which they would be able to compensate effectively under normal daytime circumstances - suggesting that any such deficits may be exposed through perturbation.

U.S. police rosters: Fatigue and public complaints.

Study Objectives: Recent experimental research indicates a substantial impact of shift work related fatigue on police officers' encounters with the public. In recent years, biomathematical models of fatigue have provided a new way to identify potential relationships between working time arrangements and job performance. This study focused on public complaints against police officers and determined whether the odds of a public complaint were associated with work schedules and/or a biomathematical model's predictions of fatigue and sleepiness.

Sleep quality, sleepiness and the influence of workplace breaks: A cross-sectional survey of health-care workers in two US hospitals.

This study assessed sleep quality, sleepiness and use of workplace break opportunities in 1285 health-care workers via an online questionnaire. Two hospitals were surveyed - one with and one without a fatigue mitigation policy. Across all respondents, 68.

Normal sleep requires the astrocyte brain-type fatty acid binding protein FABP7.

Sleep is found widely in the animal kingdom. Despite this, few conserved molecular pathways that govern sleep across phyla have been described. The mammalian brain-type fatty acid binding protein (Fabp7) is expressed in astrocytes, and its mRNA oscillates in tandem with the sleep-wake cycle.

Signal-to-Noise Ratio in PVT Performance as a Cognitive Measure of the Effect of Sleep Deprivation on the Fidelity of Information Processing.

Study Objectives: There is a long-standing debate about the best way to characterize performance deficits on the psychomotor vigilance test (PVT), a widely used assay of cognitive impairment in human sleep deprivation studies. Here, we address this issue through the theoretical framework of the diffusion model and propose to express PVT performance in terms of signal-to-noise ratio (SNR).

Methods: From the equations of the diffusion model for one-choice, reaction-time tasks, we derived an expression for a novel SNR metric for PVT performance.

Naturalistic field study of the restart break in US commercial motor vehicle drivers: Truck driving, sleep, and fatigue.

Commercial motor vehicle (CMV) drivers in the US may start a new duty cycle after taking a 34-h restart break. A restart break provides an opportunity for sleep recuperation to help prevent the build-up of fatigue across duty cycles. However, the effectiveness of a restart break may depend on its timing, and on how many nighttime opportunities for sleep it contains.

Validation of a portable, touch-screen psychomotor vigilance test.

Introduction: The Psychomotor Vigilance Test (PVT) measures effects of fatigue from sleep loss and circadian misalignment on sustained vigilance performance. To promote PVT use in field environments, a 5-min PVT version has been implemented on a personal digital assistant (PDA) with a touch screen. The present laboratory study was conducted to validate this PVT against a standard 10-min laptop PVT across 38 h of total sleep deprivation (TSD).