David Dinges

• Doctor of Philosophy
• University of Pennsylvania

Insufficient sleep compromises cognitive performance, diminishes vigilance, and disrupts daily functioning in hundreds of millions of people worldwide. Despite extensive research revealing significant variability in vigilance vulnerability to sleep deprivation, the underlying mechanisms of these individual differences remain elusive. Locus coeruleu...

Healthy sleep of sufficient duration preserves mood and disturbed sleep is a risk factor for a range of psychiatric disorders. As adults commonly experience chronic sleep restriction (SR), an enhanced understanding of the dynamic relationship between sleep and mood is needed, including whether susceptibility to SR-induced mood disturbance differs b...

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 do...

Sleep loss impacts a broad range of brain and cognitive functions. However, how sleep deprivation affects risky decision‐making remains inconclusive. This study used functional MRI to examine the impact of one night of total sleep deprivation (TSD) on risky decision‐making behavior and the underlying brain responses in healthy adults. In this study...

Physical activity has long been shown to be associated with biological and physiological performance and risk of diseases. It is of great interest to assess whether the effect of an exposure or intervention on an outcome is mediated through physical activity measured by modern wearable devices such as actigraphy. However, existing methods for media...

Background: Numerous studies summarized in a recent meta-analysis have shown sleep deprivation rapidly improves depressive symptoms in approximately 50 % of individuals with major depressive disorder (MDD), however those studies were typically conducted in clinical settings. Here we investigated the effects of sleep deprivation utilizing a highly...

Objective: Neighborhood-level factors, including education, health and environment, and socioeconomic exposures, are important contextual determinants of child health. We explored whether these factors, measured via the Childhood Opportunity Index 2.0, were associated with sleep health in adolescents. Methods: Actigraphy was used to assess sleep...

Sleep loss robustly disrupts mood and emotion regulation in healthy individuals but can have a transient antidepressant effect in a subset of patients with depression. The neural mechanisms underlying this paradoxical effect remain unclear. Previous studies suggest that the amygdala and dorsal nexus (DN) play key roles in depressive mood regulation...

Objective: Climate change and urbanization increasingly cause extreme conditions hazardous to health. The bedroom environment plays a key role for high-quality sleep. Studies objectively assessing multiple descriptors of the bedroom environment as well as sleep are scarce. Methods: Particulate matter with a particle size <2.5 µm (PM2.5), tempera...

Objective: Determine the optimal combination of digital health intervention component settings that increase average sleep duration by ≥30 minutes per weeknight. Methods: Optimization trial using a 25 factorial design. The trial included 2 week run-in, 7 week intervention, and 2 week follow-up periods. Typically developing children aged 9-12y, with...

Fatigue had classically been defined as a decrease in performance or performance capability as a function of time on task. This definition formed the basis for FAA duty time regulations for over 70 years, until January 2012, with the introduction of Part 117 Fatigue Risk Management (FRMP) regulations (FAA 14 CFR Part 117, 2013). Efforts to manage f...

Sleep is a biologic necessity that sustains life and maintains health and wellbeing. When sleep is disrupted, meaning an abnormality in duration, timing, continuity, or quality, it threatens to negatively affect a myriad of biologic functions and deteriorates health. Critically ill adults in the intensive care unit (ICU) are at high risk for sleep...

Physical activity has long been shown to be associated with biological and physiological performance and risk of diseases. It is of great interest to assess whether the effect of an exposure or intervention on an outcome is mediated through physical activity measured by modern wearable devices such as actigraphy. However, existing methods for media...

During spaceflight, astronauts face a unique set of stressors, including microgravity, isolation, and confinement, as well as environmental and operational hazards. These factors can negatively impact sleep, alertness, and neurobehavioral performance, all of which are critical to mission success. In this paper, we predict neurobehavioral performanc...

Introduction Little is known about the impact of cumulative workdays on medical residents' alertness. The purpose of this study was to examine changes in alertness over consecutive workdays following a day off for internal medicine interns. Methods This is a secondary report of a randomized non-inferiority trial of 12 internal-medicine residency p...

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 s...

Interindividual differences in the neurobehavioral response to sleep loss are largely unexplained and phenotypic in nature. Numerous factors have been examined as predictors of differential response to sleep loss, but none have yielded a comprehensive view of the phenomenon. The present study examines the impact of baseline factors, habitual sleep–...

Background Medical interns are at risk for sleep deprivation from long and often rotating work schedules. However, the effects of specific rotations on sleep are less clear. Objective To examine differences in sleep duration and alertness among internal medicine interns during inpatient intensive care unit (ICU) compared to general medicine (GM) r...

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 bio...

Introduction The global pandemic due to the novel coronavirus (COVID-19) has had unprecedented effects on society, in particular for those who are also working with children in the household. The aim of this analysis was to evaluate sleep amount and sleep quality during the COVID-19 pandemic compared to before COVID-19 for those working from home w...

Introduction In March 2020, an unprecedented number of individuals were confined to their homes in an effort to stem the spread of the novel Coronavirus (Covid-19), however the impact of this confinement on health and behavior is unknown. Long-duration confinement studies have found effects on homeostatic biology and neurobehavioral functions, incl...

Introduction As of March 2020, most U.S. states and territories issued statements advising people “stay at home” to avoid spreading the novel Coronavirus (COVID-19). This resulted in an unprecedented number of people practicing physical confinement and social distancing. This study examined self-reported changes in sleep duration, quality and timin...

Introduction Given the high prevalence and poor outcomes of insufficient child sleep, effective interventions for the pediatric primary care setting are needed. Collecting family perspectives on intervention strategies is critical to understand and enhance outcomes, particularly among children who do not experience improvements. This study examined...

Introduction We conducted a childhood sleep promotion study between March 2019 and December 2020 in Philadelphia. COVID19 was first detected in Pennsylvania in March 2020 and non-essential services were strictly curtailed (including school closures), with easing of curtailments by the fall 2020 (including hybrid schooling in some districts). We det...

Study Objectives Pediatricians lack tools to support families at home for the promotion of childhood sleep. We are using the Multiphase Optimization Strategy (MOST) framework to guide the development of a mobile health platform for childhood sleep promotion. The objective of this study is to demonstrate feasibility of a mobile health platform towar...

Environmental and psychological stressors can adversely affect astronaut cognitive performance in space. This study used a 6° head-down tilt bed rest (HDBR) paradigm to simulate some of the physiologic changes induced by microgravity. Twenty-four participants (mean ± SD age 33.3 ± 9.2 years, N = 16 men) spent 60 consecutive days in strict HDBR. The...

Microgravity and elevated CO 2 levels are two important environmental spaceflight stressors that can adversely affect astronaut cognitive performance and jeopardize mission success. This study investigated the effects of 6⁰ head-down tilt bed rest (HDBR) with (N=11 participants, 30 days HDBR) and without (N=8 participants, 60 days HDBR) elevated am...

Study Objectives Over 75% of US high school students obtain insufficient sleep, placing them at risk for adverse health outcomes. Identification of modifiable determinants of adolescent sleep is needed to inform prevention strategies, yet little is known about the influence of the built environment on adolescent sleep. Methods In this prospective...

Background Pediatricians lack tools to support families at home for the promotion of childhood sleep. We are using the Multiphase Optimization Strategy (MOST) framework to guide the development of a mobile health platform for childhood sleep promotion. Purpose Under the preparation phase of the MOST framework, to demonstrate feasibility of a mobil...

INTRODUCTION: Environmental and operational stressors commonly encountered in spaceflight can affect astronaut cognitive performance. It is currently unclear how performance decrements on test batteries that assess individual cognitive domains translate to complex operational performance. METHODS: N 30 healthy adults (mean SD age 33.5 7.1 yr, range...

Sleep restriction (SR) reliably increases caloric intake. It remains unknown whether such intake cumulatively increases with repeated SR exposures and is impacted by the number of intervening recovery sleep opportunities. Healthy adults (33.9 ± 8.9y; 17 women, Body Mass Index: 24.8 ± 3.6) participated in a laboratory protocol. N = 35 participants e...

Study Objectives The Psychomotor Vigilance Test (PVT) is frequently used to measure behavioral alertness in sleep research on various software and hardware platforms. In contrast to many other cognitive tests, PVT response time shifts of a few milliseconds can be meaningful. It is therefore important to use calibrated systems, but calibration stand...

Introduction Practice effects associated with the repeated administration of cognitive tests often confound true therapeutic or experimental effects. Alternate test forms help reduce practice effects, but generating stimulus sets with identical properties can be difficult. The main objective of this study was to disentangle practice and stimulus se...

Sleep deprivation significantly impairs a range of cognitive and brain function, particularly episodic memory and the underlying hippocampal function. However, it remains controversial whether one or two nights of recovery sleep following sleep deprivation fully restores brain and cognitive function. In this study, we used functional magnetic reson...

Introduction Chronic sleep restriction negatively effects working memory. Recovery sleep following sleep restriction partially restores working memory performance. This study examines the impact of chronic sleep restriction and subsequent recovery sleep dose on the N-Back Task (N-Back), a valid measure of working memory. Methods N=223 participants...

Introduction Over 75% of U.S. high school students obtain insufficient amounts of sleep. Identification of modifiable environmental determinants of adolescent sleep is needed to inform interventions and public health strategies, yet little is known about the influence of the built environment on adolescent sleep. We examined associations of the bui...

Introduction Little is known about the impact of specific rotations on medical residents’ sleep. The purpose of this analysis was to examine the difference in sleep duration and alertness among internal-medicine resident interns during intensive care unit (ICU) compared to general medicine (GM) rotations. Methods This is a secondary report of a ra...

Introduction The locus coeruleus (LC) plays a key role in the regulation of arousal and autonomic function. Homeostatic sleep pressure refers to the drive for sleep that increases as a saturating exponential when we stay awake and decreases exponentially when we sleep. The current study used arterial spin labeling (ASL) functional magnetic resonanc...

Introduction Fatigue is one contributor to mood disturbance observed following sleep restriction; however, the contribution of other factors remains unclear. This study examined contributions to mood disturbance resulting from sleep restriction beyond that of fatigue, evaluated the benefit of recovery sleep, and assessed whether recovery sleep buff...

Introduction Locus coeruleus (LC) is the major source of norepinephrine (NE) in the brain, which plays a key role in maintaining arousal and alertness. Sleep loss significantly impairs arousal and alertness. However, it is unknown whether sleep loss disrupts LC integrity, which can be measured non-invasively by diffusion tensor imaging (DTI). In th...

Introduction Over half of school-aged children sleep insufficiently and sleep promoting interventions are urgently needed. To effectively promote pediatric sleep health, it is critical to obtain feedback from youth and their families about acceptable intervention strategies. This qualitative study examined perceptions about healthy sleep promotion...

Introduction Duty hour regulations affect resident sleep, education, and patient care in complex ways. We performed a national cluster-randomized trial (iCOMPARE) in 63 internal medicine residency programs comparing the effects of the 2011 duty-hour standards to a more flexible set of duty hour rules characterized by maintaining an 80-hour workweek...

Introduction Sleep restriction disturbs mood, impairs neurocognitive performance, and elevates proinflammatory cytokine levels. However, whether basal inflammation influences mood and neurocognitive performance across sleep restriction is unknown. This study examines whether baseline IL-6, cortisol, and TNF-α levels predict the deterioration of moo...

Introduction Negativity bias in depression has been repeatedly demonstrated in the judgment and decision-making literature. Research investigating the impact of sleep deprivation on self-evaluation of performance in healthy or depressed populations is limited. We examined 1) whether individuals with Major Depressive Disorder (MDD) exhibit a negativ...

Maintaining optimal cognitive performance in astronauts during spaceflight is critical to crewmember safety and mission success. To investigate the combined effects of confinement, isolation, and sleep deprivation on cognitive performance during spaceflight, we administered the computerized neurobehavioral test battery “Cognition” to crew members o...

Vigilance deficits account for a substantial number of accidents and errors. Current techniques to detect vigilance impairment measure only the most severe level evident in eyelid closure and falling asleep, which is often too late to avoid an accident or error. The present study sought to identify ocular biometrics of intermediate impairment of vi...

BACKGROUND: Cognition is a neurocognitive test battery created at the University of Pennsylvania and adapted by the National Aeronautics and Space Administration (NASA). It comprises 10 neurocognitive tests that examine multiple domains, and has been validated in a normative sample of STEM-educated adults and compared to NASA's WinSCAT battery.METH...

The neurobehavioral risks associated with spaceflight are not well understood. In particular, little attention has been paid on the role of resilience, social processes and emotion regulation during long-duration spaceflight. Bed rest is a well-established spaceflight analogue that combines the adaptations associated with physical inactivity and se...

Introduction An observational study of CMV drivers was undertaken to assess the operational, safety, health, and fatigue impacts of the restart provisions in Sections 395.3(c) and 395.3(d) of Title 49, Code of Federal Regulations. Methods N=235 drivers (224 males, 20-69y) participated in an observational study for up to 5 months duration. All driv...

Introduction Sleep deprivation results in rapid antidepressant effects in 50% of individuals with Major Depressive Disorder (MDD). However, this antidepressant effect is typically reversed by recovery sleep. More recently, it has been shown that BDNF, a key component in regulating neuroplasticity, is both reduced in MDD, and increases following tre...

Introduction The psychomotor vigilance task (PVT) is frequently used as a measure of alertness in studies of sleep loss in healthy individuals. However, very little is known about PVT performance in clinical samples. Differences in attention and vigilance stemming from affective disorders may present a potential confound in clinical PVT data. We ex...

To understand the health impact of long-duration spaceflight, one identical twin astronaut was monitored before, during, and after a 1-year mission onboard the International Space Station; his twin served as a genetically matched ground control. Longitudinal assessments identified spaceflight-specific changes, including decreased body mass, telomer...

Objectives: To compare sleep, work hours, and behavioral alertness in faculty and fellows during a randomized trial of nighttime in-hospital intensivist staffing compared with a standard daytime intensivist model. Design: Prospective observational study. Setting: Medical ICU of a tertiary care academic medical center during a randomized contro...

Background A purpose of duty-hour regulations is to reduce sleep deprivation in medical trainees, but their effects on sleep, sleepiness, and alertness are largely unknown. Methods We randomly assigned 63 internal-medicine residency programs in the United States to follow either standard 2011 duty-hour policies or flexible policies that maintained...

Background Concern persists that extended shifts in medical residency programs may adversely affect patient safety. Methods We conducted a cluster-randomized noninferiority trial in 63 internal-medicine residency programs during the 2015–2016 academic year. Programs underwent randomization to a group with standard duty hours, as adopted by the Acc...

Study Objectives Prescription sleep aids are frequently used in the general population, and even more frequently in spaceflight. To evaluate the risk to operational safety, a ground-based, double-blind, placebo-controlled study on the emergent awakening effects of zolpidem and zaleplon was conducted. Methods N=34 subjects (age M=42.1±9.7; 25 males...

Study Objective Sleep deprivation significantly reduces the ability to maintain a consistent alertness level and impairs vigilant attention. Previous studies have shown that longer inter-stimulus intervals (ISI) are associated with faster reaction times (RT) on the Psychomotor Vigilance Test (PVT). However, whether and how sleep deprivation interac...

Introduction Medical trainees’ duty hours have received attention globally; restrictions in Europe, New Zealand and some Canadian provinces are much lower than the 80 hours per week enforced in USA. In USA, resident duty hours have been implemented without evidence simultaneously reflecting competing concerns about patient safety and physician educ...

Introduction Sleep deprivation (SD) significantly impairs vigilance attention and reduces the ability to maintain a consistent alertness level. The Psychomotor Vigilance Test (PVT) is a widely used and highly sensitive vigilance task for sleep studies, which records reaction times (RT) to visual stimuli that occurs at random inter-stimulus interval...

Introduction Sleep plays a key role in the restoration and preservation of optimal brain function, whereas sleep loss causes fatigue and impairs a range of neurobehavioral functions. Accumulating evidence suggests that the human brain can be characterized as a small-world network. However, the effects of sleep deprivation (SD) and recovery sleep on...

Introduction We investigated whether phenotypic differences in neurobehavioral response to chronic partial sleep restriction were associated with baseline sleep propensity. Methods N=306 healthy adults were randomized to 5 consecutive days of sleep restriction (n=278; 4h TIB, SR1-SR5) or to a control condition (n=28; 10h TIB) after 2 baseline nigh...

Background Concern persists that inflexible duty-hour rules in medical residency programs may adversely affect the training of physicians. Methods We randomly assigned 63 internal medicine residency programs in the United States to be governed by standard duty-hour policies of the 2011 Accreditation Council for Graduate Medical Education (ACGME) o...

This article summarizes the recommendations on data and methodology issues for studying commercial motor vehicle driver fatigue of a National Academies of Sciences, Engineering, and Medicine study. A framework is provided that identifies the various factors affecting driver fatigue and relating driver fatigue to crash risk and long-term driver heal...

Study Objectives Significant interindividual variability in sleepiness is observed in clinical populations with obstructive sleep apnea (OSA). This phenomenon is only partially explained by the apnea–hypopnea index (AHI). Understanding factors that lead to sleepiness is critical to effective management of patients with OSA. We examined demographic...

Study Objectives The high prevalence of chronic insufficient sleep in the population has been a concern due to the associated health and safety risks. We evaluated secular trends in sleep duration over the most recent 14-year period. Methods The American Time Use Survey (ATUS), representative of US residents ≥15 years, was used to investigate tren...

The problems of diagnosing multiple personality disorder in a Forensic context are discussed, and illustrated by the case of State v. Kenneth Bianchi (1979), a defendant who was both charged with first degree murder and suspected of having the disorder. Because of the secondary gain (e.g., avoiding the death penalty) associated with the diagnosis o...

Microgravity and elevated levels of CO2 are two common environmental stressors in spaceflight that may affect cognitive performance of astronauts. In this randomized, double-blind, cross-over trial (SPACECOT), N=6 healthy males (mean{plus minus}SD age: 41{plus minus}5yr) were exposed to 0.04% (ambient air) and 0.5% CO2 concentrations during 26.5-ho...

Study Objectives The Psychomotor Vigilance Test (PVT) is reported to be free of practice effects that can otherwise confound the effects of sleep loss and circadian misalignment on performance. This differentiates the PVT from more complex cognitive tests. To our knowledge, no study has systematically investigated practice effects on the PVT across...

Background: Neuropsychological changes that may occur due to the environmental and psychological stressors of prolonged spaceflight motivated the development of the Cognition Test Battery. The battery was designed to assess multiple domains of neurocognitive functions linked to specific brain systems. Tests included in Cognition have been validate...

Objective: To provide a quantitative meta-analysis of the antidepressant effects of sleep deprivation to complement qualitative reviews addressing response rates. Data sources: English-language studies from 1974 to 2016 using the keywords sleep deprivation and depression searched through PubMed and PsycINFO databases. Study selection: A total...

Introduction Acute sleep deprivation (SD), either total or partial, is a well-known non-pharmacologic treatment for depression that produces clinical improvement in depression symptoms within a single 24-hour period and, as such, is one of the most rapid antidepressant interventions known. Studies of SD typically report a 40% to 60% response rate,...

Study Objectives Fatigue from sleep loss is a risk to physician and patient safety, but objective data on physician sleep and alertness on different duty hour schedules is scarce. This study objectively quantified differences in sleep duration and alertness between medical interns working extended overnight shifts and residents not or rarely workin...

Significance It is widely presumed that there is a relationship between sleep and the gut microbiome because both sleep restriction and dysbiosis of the gut microbiome are associated with metabolic diseases such as obesity and diabetes. Here, we report sleep restriction over several consecutive days does not overtly influence the composition of the...

Human space-exploration missions depend critically on the ability of crews to maintain high levels of cognitive performance throughout their missions despite exposure to a wide range of environmental conditions and stressors. These missions can involve disruptions to sleep and circadian rhythms, periods of excessive workload, and other neurobehavio...

Study objectives: We objectively measured body composition, energy expenditure, caloric intake and sleep in a large, diverse sample of healthy men and women and determined how energy balance and diet associated with sleep physiology. Methods: Healthy adults (n=50; 21-50y) participated in an in-laboratory study involving two baseline sleep nights...

Objective: Suicide is a major public health problem and the 10th leading cause of death in the United States. The identification of modifiable risk factors is essential for reducing the prevalence of suicide. Recently, it has been shown that insomnia and nightmares significantly increase the risk for suicidal ideation, attempted suicide, and death...

Study objective: The primary objective of this study was to describe characteristics of sleep across these three domains in community-dwelling adults with heart failure. The secondary objective was to identify modifiable factors associated with behavioral alertness. Methods: A sample of 280 adults with chronic heart failure was enrolled. Widely...

The impact of advances in sleep and circadian sciences over the last 20 years on medicine, health, and public safety has been limited in part by the lack of availability of objective tools capable of quantifying sleep and circadian function in point-of-care settings. This whitepaper is a product of a workshop that was designed to bring together tho...

Study objectives: Apnea-hypopnea index (AHI) is the primary measure used to confirm a diagnosis of obstructive sleep apnea (OSA). However, there may be significant night-to-night variability (NNV) in AHI, limiting the value of AHI in clinical decision-making related to OSA management. We examined short-term NNV in AHI and its predictors during hom...

Exploration-type missions will require humans to live in isolated, confined, and extreme environments for prolonged periods of time. NASA’s Mars Design Reference Mission 5.0 has a duration of 910 days, which is well beyond the duration astronauts and cosmonauts have remained confined in a spacecraft. NASA’s recent evidence-based review of the behav...

A congressionally-mandated naturalistic study was conducted to evaluate the operational, safety, fatigue, and health impacts of the restart provisions in Sections 395.3(c) and 395.3(d) of Title 49, Code of Federal Regulations. A total of 235 commercial motor vehicle drivers representative of the industry contributed data while working their normal...

Objective: Short sleep duration is a significant risk factor for weight gain, particularly in African Americans and men. Increased caloric intake underlies this relationship, but it remains unclear whether decreased energy expenditure is a contributory factor. The current study assessed the impact of sleep restriction and recovery sleep on energy...