Cognitive consequences of sleep and sleep loss

Dietary inflammatory index (DII) and sleep quality, duration, and timing: A systematic review

Sleep has strong inflammatory underpinnings and diet is one of the primary determinants of systemic inflammation. A systematic literature review was conducted to synthesize current research associating dietary inflammatory potential, as measured by the dietary inflammatory index (DII®) or the energy-adjusted DII (E-DII™) and sleep quality and duration. The National Library of Medicine (Medline), Web of Science, and PsycInfo databases were searched through March 2023. Studies must have used the DII/E-DII as the independent variable and sleep outcomes as dependent variables. Study characteristics, based on STROBE guidelines, were scored based on the presence of the recommendation. Out of the initial 14 studies identified, a total of 12 studies were included for data synthesis. In all 12 studies, more anti-inflammatory diets (i.e., low DII/E-DII scores) were associated with better sleep in at least one sleep domain (most often sleep efficiency and wake-after-sleep-onset). Among those studies with more rigorous diet and sleep measurements, such as dietary recalls and actigraphy, associations between DII/E-DII and sleep outcomes were stronger and more consistent compared to studies using primarily subjective assessments. More rigorous measurement of diet and sleep, especially those relating to sleep stage structure, should be considered in future studies with prospective designs.

The organization of sleep-wake patterns around daily schedules in college students

The amount of time available in a day is fixed, and consequently, sleep is often sacrificed for waking activities. For college students, daily activities, comprised of scheduled classes, work, study, social, and other extracurricular events, are major contributors to insufficient and poor-quality sleep. We investigated the impact of daily schedules on sleep-wake timing in 223 undergraduate students (age: 18-27 years, 37% females) from a United States university, who were monitored for ~30 days. Sleep-wake timing and daily recorded activities (attendance at academic, studying, exercise-based, and/or extracurricular activities) were captured by a twice-daily internet-based diary. Wrist-worn actigraphy was conducted to confirm sleep-wake timing. Linear mixed models were used to quantify associations between daily schedule and sleep-wake timing at between-person and within-person levels. Later scheduled start time predicted later sleep onset (between and within: p < .001), longer sleep duration on the previous night (within: p < .001), and later wake time (between and within: p < .001). Later schedule end time predicted later sleep onset (within: p < .001) and shorter sleep duration that night (within: p < .001). For every 1 hour that activities extended beyond 10 pm, sleep onset was delayed by 15 minutes at the within-person level and 40 minutes at the between-person level, and sleep duration was shortened by 6 and 23 minutes, respectively. Increased daily documented total activity time predicted earlier wake (between and within: p < .001), later sleep onset that night (within: p < .05), and shorter sleep duration (within: p < .001). These results indicate that daily schedules are an important factor in sleep timing and duration in college students. Clinical Trial: Multi-scale Modeling of Sleep Behaviors in Social Networks; URL: https://clinicaltrials.gov/study/NCT02846077; Registration:NCT02846077.

Decisional style, sleepiness, and online responsiveness

As sleep problems can impair quality of work, an online questionnaire was used to examine relationships between sleepiness and decision making while obtaining unobtrusive indices of performance. Participants (N = 344) completed the Insomnia Severity Index, Epworth Sleepiness Scale, and the Melbourne Decision Making Questionnaire in a Qualtrics survey while reporting mobile phone use. Qualtrics recorded the time and the number of clicks required to complete each page of the survey. Multiple regression indicated that insomnia was associated with daytime sleepiness and Hypervigilance, and mobile phone use before bed. Participants with moderate sleepiness required a greater number of clicks to complete the questionnaire. Greater sleepiness was associated with longer times to complete these self-assessment tasks. Clinically significant sleepiness produces changes in performance that can be detected from online responsivity. As sleepy individuals can be appreciably and quantitatively slower in performing subjective self-assessment tasks, this argues for objective measures of sleepiness and automated interventions and the design of systems that allow better quality sleep.Practitioner summary: Work can require processing of electronic messages, but 24/7 accessibility increases workload, causes fatigue and potentially creates security risks. Although most studies use people's self-reports, this study monitors time and clicks required to complete self-assessment rating scales. Sleepiness affected online responsivity, decreasing online accuracy and increasing response times and hypervigilance.

Allowing time for 8+ hours of sleep: identification and validation of important beliefs using the reasoned action approach

Introduction

The present studies advance research using the Reasoned Action Approach to understand sleep behavior. Identification of the modal salient beliefs that individuals hold regarding their sleep habits is necessary to understand the attitudes, perceived normative pressure, and perceived behavioral control (PBC) that individuals hold.

Methods

Belief elicitation (Study 1) and follow-up validation (Study 2) studies of undergraduates at a Midwestern USA university were conducted to identify readily accessible and important beliefs regarding allowing time for 8+ hours of sleep each night.

Results

Important attitude relevant beliefs included positive effects on mood, thinking, health, and productivity. Important normative beliefs were perceived injunctive pressure from family, health professionals, and significant others. Because of the strong influence of PBC on intentions/behavior, most important were control beliefs about the need for good time management.

Discussion

The present studies increased our understanding why many individuals do not allow time to obtain adequate sleep. Identification of the beliefs that distinguish between those who intend to allow time for adequate sleep and those who do not is a necessary step toward the design of effective interventions to improve sleep duration. The results indicate that a focus on increasing time management skills and PBC may be an effective approach for sleep interventions.

Assessment and Management of Sleep Disturbance in Palliative Care Settings

Background: Sleep disturbances, including insomnia, sleep-disordered breathing, and circadian rhythm disorders with potential consequences including excessive daytime somnolence and worsening fatigue, are prevalent yet largely under-measured and therefore under-managed problems in people receiving palliative care. This has the potential to negatively affect the person's functioning and quality of life. Objectives: We aimed to review the current practice of assessment and management of sleep disturbances in people with life-limiting illnesses in Australian and New Zealand palliative care settings, and to define areas for improvement in assessment and management of sleep disturbances and further research. Design: A cross-sectional, online survey was conducted with palliative care health professionals (PCHPs) to explore current approaches to routine assessment of sleep disturbances and PCHPs' awareness of, and perceived access to, evidence-based resources for assessing and managing sleep disturbances in their local settings. Results: Fifty-four PCHPs responded to the survey, including allied health professionals (44%), palliative care nurses (26%), and physicians (19%). Over 70% of PCHPs endorsed routine verbal screening of sleep symptoms, and >90% recommended management with basic behavioral strategies. However, none of PCHPs used validated patient-reported outcome measures for sleep, and <10% of PCHPs demonstrated awareness or use of sleep-specific interventions (including medications). Only 40% reported they had access to sleep specialist services for patients. Conclusion: Our findings provide a useful snapshot of current approaches to managing sleep disturbances in palliative care. Gaps in current practice are highlighted, including the lack of structured, clinical assessment, referral pathways, and PCHPs' perceived lack of access to targeted interventions for sleep disturbances.

Brain vital sign monitoring of sleep deprivation detects situational cognitive impairment

Objective, rapid evaluation of cognitive function is critical for identifying situational impairment due to sleep deprivation. The present study used brain vital sign monitoring to evaluate acute changes in cognitive function for healthy adults. Thirty (30) participants were scanned using portable electroencephalography before and after either a night of regular sleep or a night of total sleep deprivation. Brain vital signs were extracted from three established event-related potential components: (1) the N100 (Auditory sensation); (2) the P300 (Basic attention); and (3) the N400 (Cognitive processing) for all time points. As predicted, the P300 amplitude was significantly reduced in the sleep deprivation group. The findings indicate that it is possible to detect situational cognitive impairment due to sleep deprivation using objective, rapid brain vital sign monitoring.

Non-pharmacological interventions to improve sleep quality and quantity for hospitalized adult patients-co-produced study with surgical patient partners: systematic review

BACKGROUND

Hospitalized patients experience sleep disruption with consequential physiological and psychological effects. Surgical patients are particularly at risk due to surgical stress and postoperative pain. This systematic review aimed to identify non-pharmacological interventions for improving sleep and exploring their effects on sleep-related and clinical outcomes.

METHODS

A systematic literature search was performed in accordance with PRISMA guidelines and was preregistered on the Open Science Framework (doi: 10.17605/OSF.IO/EA6BN) and last updated in November 2023. Studies that evaluated non-pharmacological interventions for hospitalized, adult patients were included. Thematic content analysis was performed to identify hypothesized mechanisms of action and modes of administration, in collaboration with a patient partner. Risk of bias assessment was performed using the Cochrane Risk Of Bias (ROB) or Risk Of Bias In Non-Randomized Studies - of Interventions (ROBINS-I) tools.

RESULTS

A total of 59 eligible studies and data from 14 035 patients were included; 28 (47.5%) were randomized trials and 26 included surgical patients (10 trials). Thirteen unique non-pharmacological interventions were identified, 17 sleep measures and 7 linked health-related outcomes. Thematic analysis revealed two major themes for improving sleep in hospital inpatients: enhancing the sleep environment and utilizing relaxation and mindfulness techniques. Two methods of administration, self-administered and carer-administered, were identified. Environmental interventions, such as physical aids, and relaxation interventions, including aromatherapy, showed benefits to sleep measures. There was a lack of standardized sleep measurement and an overall moderate to high risk of bias across all studies.

CONCLUSIONS

This systematic review has identified several sleep interventions that are likely to benefit adult surgical patients, but there remains a lack of high-quality evidence to support their routine implementation.

Sleep and cognition in South African patients with non-functioning pituitary adenomas

Strong lines of evidence in the neuroscience literature indicate that (a) healthy sleep facilitates cognitive processing, and (b) sleep disruption is associated with cognitive dysfunction. Despite the fact that patients with pituitary disease often display both disrupted sleep and cognitive dysfunction, few previous studies investigate whether these clinical characteristics in these patients might be related. Hence, we explored whether sleep disruption in patients with pituitary disease mediates their cognitive dysfunction. We recruited 18 patients with non-functioning pituitary adenomas (NFPA) and 19 sociodemographically matched healthy controls. They completed the Global Sleep Assessment Questionnaire (thus providing self-report data regarding sleep disruption) and were administered the Brief Test of Adult Cognition by Telephone, which assesses cognitive functioning in the domains of processing speed, working memory, episodic memory, inhibition, and reasoning. We found no significant differences in cognition between patients and controls. Furthermore, spectra of sleep disturbance did not differ significantly between patients and controls. Our data suggest that NFPA patients' cognition and sleep quality is relatively intact, and that sleep disruption does not mediate cognitive dysfunction. Larger studies should characterize sleep and cognition in patients with NFPA (and other pituitary diseases) to confirm whether disruption of the former mediates impairment in the latter.

Development and validation of a sleep questionnaire, SNoRE 3.0, to evaluate sleep in companion dogs

Disturbances in the sleep-wake cycle are a debilitating, yet rather common condition not only in humans, but also in family dogs. While there is an emerging need for easy-to-use tools to document sleep alterations (in order to ultimately treat and/or prevent them), the veterinary tools which yield objective data (e.g. polysomnography, activity monitors) are both labor intensive and expensive. In this study, we developed a modified version of a previously used sleep questionnaire (SNoRE) and determined criterion validity in companion dogs against polysomnography and physical activity monitors (PAMs). Since a negative correlation between sleep time and cognitive performance in senior dogs has been demonstrated, we evaluated the correlation between the SNoRE scores and the Canine Dementia Scale (CADES, which includes a factor concerning sleep). There was a significant correlation between SNoRE 3.0 questionnaire scores and polysomnography data (latency to NREM sleep, ρ = 0.507, p < 0.001) as well as PAMs' data (activity between 1:00 and 3:00 AM, p < 0.05). There was a moderate positive correlation between the SNoRE 3.0 scores and the CADES scores (ρ = 0.625, p < 0.001). Additionally, the questionnaire structure was validated by a confirmatory factor analysis, and it also showed an adequate test-retest reliability. In conclusion the present paper describes a valid and reliable questionnaire tool, that can be used as a cost-effective way to monitor dog sleep in clinical settings.

Current status and prospects of automatic sleep stages scoring: Review

The scoring of sleep stages is one of the essential tasks in sleep analysis. Since a manual procedure requires considerable human and financial resources, and incorporates some subjectivity, an automated approach could result in several advantages. There have been many developments in this area, and in order to provide a comprehensive overview, it is essential to review relevant recent works and summarise the characteristics of the approaches, which is the main aim of this article. To achieve it, we examined articles published between 2018 and 2022 that dealt with the automated scoring of sleep stages. In the final selection for in-depth analysis, 125 articles were included after reviewing a total of 515 publications. The results revealed that automatic scoring demonstrates good quality (with Cohen's kappa up to over 0.80 and accuracy up to over 90%) in analysing EEG/EEG + EOG + EMG signals. At the same time, it should be noted that there has been no breakthrough in the quality of results using these signals in recent years. Systems involving other signals that could potentially be acquired more conveniently for the user (e.g. respiratory, cardiac or movement signals) remain more challenging in the implementation with a high level of reliability but have considerable innovation capability. In general, automatic sleep stage scoring has excellent potential to assist medical professionals while providing an objective assessment.

Widespread psychoactive pollutant augments daytime restfulness and disrupts diurnal activity rhythms in fish

Pharmaceutical pollution is a major driver of global change, with the capacity to alter key behavioural and physiological traits in exposed animals. Antidepressants are among the most commonly detected pharmaceuticals in the environment. Despite well-documented pharmacological effects of antidepressants on sleep in humans and other vertebrates, very little is known about their ecologically relevant impacts as pollutants on non-target wildlife. Accordingly, we investigated the effects of acute 3-day exposure of eastern mosquitofish (Gambusia holbrooki) to field-realistic levels (nominal concentrations: 30 and 300 ng/L) of the widespread psychoactive pollutant, fluoxetine, on diurnal activity patterns and restfulness, as indicators of disruptions to sleep. We show that exposure to fluoxetine disrupted diel activity patterns, which was driven by augmentation of daytime inactivity. Specifically, unexposed control fish were markedly diurnal, swimming farther during the day and exhibiting longer periods and more bouts of inactivity at night. However, in fluoxetine-exposed fish, this natural diel rhythm was eroded, with no differences in activity or restfulness observed between the day and night. As a misalignment in the circadian rhythm has been shown to adversely affect fecundity and lifespan in animals, our findings reveal a potentially serious threat to the survival and reproductive success of pollutant-exposed wildlife.

The stress of losing sleep: Sex-specific neurobiological outcomes

Sleep is a vital and evolutionarily conserved process, critical to daily functioning and homeostatic balance. Losing sleep is inherently stressful and leads to numerous detrimental physiological outcomes. Despite sleep disturbances affecting everyone, women and female rodents are often excluded or underrepresented in clinical and pre-clinical studies. Advancing our understanding of the role of biological sex in the responses to sleep loss stands to greatly improve our ability to understand and treat health consequences of insufficient sleep. As such, this review discusses sex differences in response to sleep deprivation, with a focus on the sympathetic nervous system stress response and activation of the hypothalamic-pituitary-adrenal (HPA) axis. We review sex differences in several stress-related consequences of sleep loss, including inflammation, learning and memory deficits, and mood related changes. Focusing on women's health, we discuss the effects of sleep deprivation during the peripartum period. In closing, we present neurobiological mechanisms, including the contribution of sex hormones, orexins, circadian timing systems, and astrocytic neuromodulation, that may underlie potential sex differences in sleep deprivation responses.

Learning to Learn: A pilot study on explicit strategy instruction to incoming college students

The current pilot study implemented a "Learning to Learn" (L2L) course designed to teach first-year college students about the science of how learning works, how to take ownership of their own learning, and how to effectively apply learning strategies to achieve their academic goals. A cognitive apprenticeship model was used in which students planned, executed, and evaluated strategy use in vivo during the course. Two sections of the course were taught at each of two different institutions, distributed across four semesters. Quantitative data showed an increased growth mindset among L2L students at the end of the semester compared to the beginning of the semester. In contrast, first-year students surveyed from control groups in the same semester had a decreased growth mindset. Furthermore, compared to students in the control groups, students in the L2L courses maintained more stable levels of effort across the semester and felt more in control of their learning by the end of the semester. Qualitative data collected from focus groups indicated that the L2L students continued to use the strategies they had learned in the course in the subsequent semester, and that the changes in their perceptions about growth mindset continued beyond the duration of the course. Several L2L students noted a desire for the learning strategies to be taught earlier in their education. Next steps involve feasibility studies on appropriate scaling to support more undergraduates each year, and to support students during the critical transition from K-12 schooling to the college environment.

An online diary study testing the role of functional and dysfunctional self-licensing in unhealthy snacking

In the present study, we aimed to investigate how two types of self-licensing (functional and dysfunctional self-licensing) are related to unhealthy snack consumption. Self-licensing refers to the act of using justifications before gratifications and has been associated with higher snack consumption. Previous research has found that while functional self-licensing decreases unhealthy snack consumption, dysfunctional self-licensing increases the number of calories taken from unhealthy snacks. Building upon existing evidence, we addressed functional and dysfunctional self-licensing to investigate how self-licensing behaviors are associated with daily variables (i.e., stress and sleep) and unhealthy snacking habits. Participants (N = 124) were given a battery of measures at the start of the week and asked to send their snack consumption every night for a week via an online questionnaire, along with daily stress and sleep items. The data were analyzed with Hierarchical Linear Modelling. Neither self-licensing measures nor unhealthy snacking habits predicted unhealthy snack consumption. Daily stress was associated with lower unhealthy snack consumption. However, the interaction between daily stress and functional self-licensing was significant, suggesting that on stressful days functional self-licensers consume even fewer unhealthy snacks compared to less stressful days. Functional and dysfunctional self-licensing are rather new constructs which is why examining their effects is important for further research. However, in contrast to the existing evidence, we failed to find an effect of both types of self-licensing on snack consumption, suggesting the effect depends on potential contextual or individual-specific factors. Future research using a dieting sample is warranted for a better understanding of how functional and dysfunctional self-licensing operate.

Associations between the Dietary Inflammatory Index and Sleep Metrics in the Energy Balance Study (EBS)

(1) Background: Sleep, a physiological necessity, has strong inflammatory underpinnings. Diet is a strong moderator of systemic inflammation. This study explored the associations between the Dietary Inflammatory Index (DII®) and sleep duration, timing, and quality from the Energy Balance Study (EBS). (2) Methods: The EBS (n = 427) prospectively explored energy intake, expenditure, and body composition. Sleep was measured using BodyMedia’s SenseWear® armband. DII scores were calculated from three unannounced dietary recalls (baseline, 1-, 2-, and 3-years). The DII was analyzed continuously and categorically (very anti-, moderately anti-, neutral, and pro-inflammatory). Linear mixed-effects models estimated the DII score impact on sleep parameters. (3) Results: Compared with the very anti-inflammatory category, the pro-inflammatory category was more likely to be female (58% vs. 39%, p = 0.02) and African American (27% vs. 3%, p < 0.01). For every one-unit increase in the change in DII score (i.e., diets became more pro-inflammatory), wake-after-sleep-onset (WASO) increased (βChange = 1.00, p = 0.01), sleep efficiency decreased (βChange = −0.16, p < 0.05), and bedtime (βChange = 1.86, p = 0.04) and waketime became later (βChange = 1.90, p < 0.05). Associations between bedtime and the DII were stronger among African Americans (βChange = 6.05, p < 0.01) than European Americans (βChange = 0.52, p = 0.64). (4) Conclusions: Future studies should address worsening sleep quality from inflammatory diets, leading to negative health outcomes, and explore potential demographic differences.

Sleep-mediated regulation of reward circuits: implications in substance use disorders

Our modern society suffers from both pervasive sleep loss and substance abuse-what may be the indications for sleep on substance use disorders (SUDs), and could sleep contribute to the individual variations in SUDs? Decades of research in sleep as well as in motivated behaviors have laid the foundation for us to begin to answer these questions. This review is intended to critically summarize the circuit, cellular, and molecular mechanisms by which sleep influences reward function, and to reveal critical challenges for future studies. The review also suggests that improving sleep quality may serve as complementary therapeutics for treating SUDs, and that formulating sleep metrics may be useful for predicting individual susceptibility to SUDs and other reward-associated psychiatric diseases.

Posttraumatic stress symptoms and substance use among college students: Exploring interactions with sleep quality and assigned sex

Substance use is widely recognized as a negative outcome following traumatic events and is tied to symptoms of posttraumatic stress (PTS). Sleep quality may influence the PTS and substance use association, particularly among college students who are at risk for poor sleep. The purpose of the present study was to examine the moderating effect of sleep quality on the relationship between PTS and substance use in a cohort of college students, with an exploratory aim of examining potential differences by assigned sex. A screening survey was completed by 2,767 students enrolled in a larger RCT examining various brief college student alcohol reduction strategies. Results found a significant two-way interaction between PTS symptoms and subjective sleep quality on weekly number of drinks and peak drinking occasion, where the significant positive association between PTS symptoms to weekly drinks and peak drinking occasion was only found for those who reported poor sleep quality. A similar pattern emerged for the significant two-way interaction between PTS symptoms and subjective sleep quality on cannabis use frequency. A significant three-way interaction (i.e., PTS Symptoms × Poor Subjective Sleep Quality × Assigned Sex) indicated the two-way interaction between PTS symptoms and sleep quality for both weekly drinks and cannabis use frequency was stronger among male compared to female participants. Study findings suggest sleep quality is an important factor contributing to the relation between PTS symptom severity and substance use among college students. Strategies for assessing and improving sleep quality and PTS symptoms can be incorporated into prevention and intervention efforts targeting substance use related harm for college students.

Sleep, Circadian Rhythms, and Cognitive Dysfunction in Huntington's Disease

BACKGROUND

In healthy people, sleep and circadian disruption are linked to cognitive deficits. People with Huntington's disease (HD), who have compromised brain function and sleep and circadian disturbances, may be even more susceptible to these cognitive effects.

OBJECTIVE

To conduct a comprehensive review and synthesis of the literature in HD on the associations of cognitive dysfunction with disturbed sleep and circadian rhythms.

METHODS

We searched MEDLINE via OVID, CINAHL Plus, EMBASE via OVID, and PubMed in May 2023. The first author then screened by title and abstract and conducted a full review of remaining articles.

RESULTS

Eight studies investigating the influence of sleep and/or circadian rhythms on cognitive function in HD were found. In manifest HD, poorer sleep was associated with worse cognitive function. For behavioral 24-hour (circadian) rhythms, two studies indicated that later wake times correlated with poorer cognitive function. No reported studies in HD examined altered physiological 24-hour (circadian) rhythms and cognitive impairment.

CONCLUSION

Some associations exist between poor sleep and cognitive dysfunction in manifest HD, yet whether these associations are present before clinical diagnosis is unknown. Whether circadian disturbances relate to cognitive impairment in HD also remains undetermined. To inform sleep and circadian interventions aimed at improving cognitive symptoms in HD, future research should include a range of disease stages, control for external factors, and utilize robust cognitive batteries targeted to the aspects of cognitive function known to be adversely affected in HD.

Effects of Acute Sleep Loss on Physical Performance: A Systematic and Meta-Analytical Review

BACKGROUND

Sleep loss may influence subsequent physical performance. Quantifying the impact of sleep loss on physical performance is critical for individuals involved in athletic pursuits.

DESIGN

Systematic review and meta-analysis.

SEARCH AND INCLUSION

Studies were identified via the Web of Science, Scopus, and PsycINFO online databases. Investigations measuring exercise performance under 'control' (i.e., normal sleep, > 6 h in any 24 h period) and 'intervention' (i.e., sleep loss, ≤ 6 h sleep in any 24 h period) conditions were included. Performance tasks were classified into different exercise categories (anaerobic power, speed/power endurance, high-intensity interval exercise (HIIE), strength, endurance, strength-endurance, and skill). Multi-level random-effects meta-analyses and meta-regression analyses were conducted, including subgroup analyses to explore the influence of sleep-loss protocol (e.g., deprivation, restriction, early [delayed sleep onset] and late restriction [earlier than normal waking]), time of day the exercise task was performed (AM vs. PM) and body limb strength (upper vs. lower body).

RESULTS

Overall, 227 outcome measures (anaerobic power: n = 58; speed/power endurance: n = 32; HIIE: n = 27; strength: n = 66; endurance: n = 22; strength-endurance: n = 9; skill: n = 13) derived from 69 publications were included. Results indicated a negative impact of sleep loss on the percentage change (%Δ) in exercise performance (n = 959 [89%] male; mean %Δ =  - 7.56%, 95% CI - 11.9 to - 3.13, p = 0.001, I2 = 98.1%). Effects were significant for all exercise categories. Subgroup analyses indicated that the pattern of sleep loss (i.e., deprivation, early and late restriction) preceding exercise is an important factor, with consistent negative effects only observed with deprivation and late-restriction protocols. A significant positive relationship was observed between time awake prior to the exercise task and %Δ in performance for both deprivation and late-restriction protocols (~ 0.4% decrease for every hour awake prior to exercise). The negative effects of sleep loss on different exercise tasks performed in the PM were consistent, while tasks performed in the AM were largely unaffected.

CONCLUSIONS

Sleep loss appears to have a negative impact on exercise performance. If sleep loss is anticipated and unavoidable, individuals should avoid situations that lead to experiencing deprivation or late restriction, and prioritise morning exercise in an effort to maintain performance.

Does sleep duration moderate genetic and environmental contributions to cognitive performance?

While prior research has demonstrated a relationship between sleep and cognitive performance, how sleep relates to underlying genetic and environmental etiologies contributing to cognitive functioning, regardless of the level of cognitive function, is unclear. The present study assessed whether the importance of genetic and environmental contributions to cognition vary depending on an individual's aging-related sleep characteristics. The large sample consisted of twins from six studies within the Interplay of Genes and Environment across Multiple Studies (IGEMS) consortium spanning mid- to late-life (Average age [Mage] = 57.6, range = 27-91 years, N = 7052, Female = 43.70%, 1525 complete monozygotic [MZ] pairs, 2001 complete dizygotic [DZ] pairs). Quantitative genetic twin models considered sleep duration as a primary moderator of genetic and environmental contributions to cognitive performance in four cognitive abilities (Semantic Fluency, Spatial-Visual Reasoning, Processing Speed, and Episodic Memory), while accounting for age moderation. Results suggested genetic and both shared and nonshared environmental contributions for Semantic Fluency and genetic and shared environmental contributions for Episodic Memory vary by sleep duration, while no significant moderation was observed for Spatial-Visual Reasoning or Processing Speed. Results for Semantic Fluency and Episodic Memory illustrated patterns of higher genetic influences on cognitive function at shorter sleep durations (i.e. 4 hours) and higher shared environmental contributions to cognitive function at longer sleep durations (i.e. 10 hours). Overall, these findings may align with associations of upregulation of neuroinflammatory processes and ineffective beta-amyloid clearance in short sleep contexts and common reporting of mental fatigue in long sleep contexts, both associated with poorer cognitive functioning.

Healthy Sleep Every Day Keeps the Doctor Away

When one considers the big picture of their health, sufficient sleep may often go overlooked as a keystone element in this picture. Insufficient sleep in either quality or duration is a growing problem for our modern society. It is essential to look at what this means for our health because insufficient sleep increases our risks of innumerable lifechanging diseases. Beyond increasing the risk of developing these diseases, it also makes the symptoms and pathogenesis of many diseases worse. Additionally, consistent quality sleep can not only improve our physical health but has also been shown to improve mental health and overall quality of life. Substandard sleep health could be a root cause for numerous issues individuals may be facing in their lives. It is essential that physicians take the time to learn about how to educate their patients on sleep health and try to work with them on an individual level to help motivate lifestyle changes. Facilitating access to sleep education for their patients is one way in which physicians can help provide patients with the tools to improve their sleep health. Throughout this paper, we will review the mechanisms behind the relationship between insufficient sleep health and chronic disease and what the science says about how inadequate sleep health negatively impacts the overall health and the quality of our lives. We will also explain the lifechanging effects of sufficient sleep and how we can help patients get there.

Perioperative Brain Health in the Older Adult: A Patient Safety Imperative

While people 65 years of age and older represent 16% of the population in the United States, they account for >40% of surgical procedures performed each year. Maintaining brain health after anesthesia and surgery is not only important to our patients, but it is also an increasingly important patient safety imperative for the specialty of anesthesiology. Aging is a complex process that diminishes the reserve of every organ system and often results in a patient who is vulnerable to the stress of surgery. The brain is no exception, and many older patients present with preoperative cognitive impairment that is undiagnosed. As we age, a number of changes occur in the human brain, resulting in a patient who is less resilient to perioperative stress, making older adults more susceptible to the phenotypic expression of perioperative neurocognitive disorders. This review summarizes the current scientific and clinical understanding of perioperative neurocognitive disorders and recommends patient-centered, age-focused interventions that can better mitigate risk, prevent harm, and improve outcomes for our patients. Finally, it discusses the emerging topic of sleep and cognitive health and other future frontiers of scientific inquiry that might inform clinical best practices.

Memantine for the patients with mild cognitive impairment in Parkinson's disease: a pharmacological fMRI study

BACKGROUND

Mild cognitive impairment in Parkinson's disease (PD-MCI) is associated with an increased risk of cognitive decline. PD-MCI is characterized by impairments in executive function and visuospatial recognition. The visuospatial n-back test is useful for assessing both domains. The 0-back test reflects visuospatial recognition, while the 1-back and 2-back tests reflect working memory. Cholinesterase inhibitors are effective in the treatment of PD-MCI and dementia in PD (PDD). Although some studies have reported the efficacy of memantine for PDD, the therapeutic efficacy of memantine in patients with PD-MCI remains uncertain.

METHODS

This study aimed to investigate the effects of memantine on brain function in patients with PD-MCI, using a randomized double-blinded crossover protocol and functional MRI (fMRI). Ten patients who completed 16 weeks of follow-up were included. They were randomly assigned to either the memantine or placebo. Patients in the memantine group received 5 mg/day of memantine in the first week. The memantine dose was increased by 5 mg/day per week, until a final dose of 20 mg/day. Patients in the placebo group received the placebo following the same regimen as memantine. After the intervention, they underwent a 4 weeks washout period. Following the crossover protocol, a second intervention was conducted after the washout period. In each intervention, fMRI and neuropsychological tests were performed at the maximum dose period. Comparing the memantine and placebo groups, we investigated difference in the brain regions using the visuospatial n-back test.

RESULTS

There were no significant regions enhanced by memantine comparing with placebo at any load of n-back tests. In contrast, exploring regions reduced by memantine, we found significant reduction of activations within right lingual gyrus and left superior frontal gyrus in comparison between 2-back and 0-back test. A number of correct answers of the 2-back test and time to complete Trail Making Test-A were worse during memantine intervention.

CONCLUSIONS

Memantine did not improve visuospatial working memory of the patients with PD-MCI. Treatment for PD should be planned carefully considering the impact on cognitive function. Further study is needed to establish new therapeutic strategy.

TRIAL REGISTRATION

UMIN000046104. Retrospectively registered. First registration date: 28 Sept 2017.

On the relationships between epilepsy, sleep, and Alzheimer's disease: A narrative review

Epilepsy, sleep, and Alzheimer's disease (AD) are tightly and potentially causally interconnected. The aim of our review was to investigate current research directions on these relationships. Our hope is that they may indicate preventive measures and new treatment options for early neurodegeneration. We included articles that assessed all three topics and were published during the last ten years. We found that this literature corroborates connections on various pathophysiological levels, including sleep-stage-related epileptiform activity in AD, the negative consequences of different sleep disorders on epilepsy and cognition, common biochemical pathways as well as network dysfunctions. Here we provide a detailed overview of these topics and we discuss promising diagnostic and therapeutic consequences.

Median preoptic GABA and glutamate neurons exert differential control over sleep behavior

Previous studies suggest that the median preoptic nucleus (MnPO) of the hypothalamus plays an important role in regulating the wake-sleep cycle and, in particular, homeostatic sleep drive. However, the precise cellular phenotypes, targets, and central mechanisms by which the MnPO neurons regulate the wake-sleep cycle remain unknown. Both excitatory and inhibitory MnPO neurons innervate brain regions implicated in sleep promotion and maintenance, suggesting that both cell types may participate in sleep control. Using genetically targeted approaches, we investigated the role of the MnPO GABAergic (MnPO^Vgat) and glutamatergic (MnPO^Vglut2) neurons in modulating wake-sleep behavior of mice. We found that both neuron populations differentially participate in wake-sleep control, with MnPO^Vgat neurons being involved in sleep homeostasis and MnPO^Vglut2 neurons facilitating sleep during allostatic (stressful) challenges.

Assessment of Mental Workload by Visual Motor Activity among Control Group and Patient Suffering from Depressive Disorder

Major depressive disorder (MDD) is a mood state that is not usually associated with vision problems. Recent research has found that the inhibitory neurotransmitter GABA levels in the occipital brain have dropped. Aim. The aim of the research is to evaluate mental workload by single channel electroencephalogram (EEG) approach through visual-motor activity and comparison of parameter among depressive disorder patient and in control group. Method. Two tests of a visual-motor task similar to reflect drawings were performed in this study to compare the visual information processing of patients with depression to that of a placebo group. The current study looks into the accuracy of monitoring cognitive burden with single-channel portable EEG equipment. Results. The alteration of frontal brain movement in reaction to fluctuations in cognitive burden stages generated through various vasomotor function was examined. By applying a computerised oculomotor activity analogous to reflector image diagram, we found that the complexity of the path to be drawn was more important than the real time required accomplishing the job in determining perceived difficulty in depressive disorder patients. The overall perceived difficulty of the exercise is positively linked with EEG activity measured from the motor cortex region at the start of every experiment test. The average rating for task completion for depression patients and in control group observed and no statistical significance association reported between rating scale and time spent on each trial (p=1.43) for control group while the normalised perceived difficulty rating had 0.512, 0.623, and 0.821 correlations with the length of the pathway, the integer of inclination in the pathway, and the time spent to complete every experiment test, respectively (p < 0.0001) among depression patients. The findings imply that alterations in comparative cognitive burden levels during an oculomotor activity considerably modify frontal EEG spectrum. Conclusion. Patients with depression perceived the optical illusion in the arrays as weaker, resulting in a little bigger disparity than individuals who were not diagnosed with depression. This discovery provided light on the prospect of adopting a user-friendly mobile EEG technology to assess mental workload in everyday life.

Smartphone keyboard interaction monitoring as an unobtrusive method to approximate rest-activity patterns: Inter-individual and metric-specific variations (Preprint)

BACKGROUND

Sleep is an important determinant of individuals' health and behavior during the wake phase. Novel research methods for field assessments are required to enable the monitoring of sleep over a prolonged period and across a large number of people. The ubiquity of smartphones offers new avenues for detecting rest-activity patterns in everyday life in a noninvasive an inexpensive manner and on a large scale. Recent studies provided evidence for the potential of smartphone interaction monitoring as a novel tracking method to approximate rest-activity patterns based on the timing of smartphone activity and inactivity throughout the 24-hour day. These findings require further replication and more detailed insights into interindividual variations in the associations and deviations with commonly used metrics for monitoring rest-activity patterns in everyday life.

OBJECTIVE

This study aimed to replicate and expand on earlier findings regarding the associations and deviations between smartphone keyboard-derived and self-reported estimates of the timing of the onset of the rest and active periods and the duration of the rest period. Moreover, we aimed to quantify interindividual variations in the associations and time differences between the 2 assessment modalities and to investigate to what extent general sleep quality, chronotype, and trait self-control moderate these associations and deviations.

METHODS

Students were recruited to participate in a 7-day experience sampling study with parallel smartphone keyboard interaction monitoring. Multilevel modeling was used to analyze the data.

RESULTS

In total, 157 students participated in the study, with an overall response rate of 88.9% for the diaries. The results revealed moderate to strong relationships between the keyboard-derived and self-reported estimates, with stronger associations for the timing-related estimates (β ranging from .61 to .78) than for the duration-related estimates (β=.51 and β=.52). The relational strength between the time-related estimates was lower, but did not substantially differ for the duration-related estimates, among students experiencing more disturbances in their general sleep quality. Time differences between the keyboard-derived and self-reported estimates were, on average, small (<0.5 hours); however, large discrepancies were also registered for quite some nights. The time differences between the 2 assessment modalities were larger for both timing-related and rest duration-related estimates among students who reported more disturbances in their general sleep quality. Chronotype and trait self-control did not significantly moderate the associations and deviations between the 2 assessment modalities.

CONCLUSIONS

We replicated the positive potential of smartphone keyboard interaction monitoring for estimating rest-activity patterns among populations of regular smartphone users. Chronotype and trait self-control did not significantly influence the metrics' accuracy, whereas general sleep quality did: the behavioral proxies obtained from smartphone interactions appeared to be less powerful among students who experienced lower general sleep quality. The generalization and underlying process of these findings require further investigation.

Sleep as a predictor of tDCS and language therapy outcomes

STUDY OBJECTIVES

To determine whether sleep at baseline (before therapy) predicted improvements in language following either language therapy alone or coupled with transcranial direct current stimulation (tDCS) in individuals with primary progressive aphasia (PPA).

METHODS

Twenty-three participants with PPA (mean age 68.13 ± 6.21) received written naming/spelling therapy coupled with either anodal tDCS over the left inferior frontal gyrus (IFG) or sham condition in a crossover, sham-controlled, double-blind design (ClinicalTrials.gov identifier: NCT02606422). The outcome measure was percent of letters spelled correctly for trained and untrained words retrieved in a naming/spelling task. Given its particular importance as a sleep parameter in older adults, we calculated sleep efficiency (total sleep time/time in bed x100) based on subjective responses on the Pittsburgh Sleep Quality Index (PSQI). We grouped individuals based on a median split: high versus low sleep efficiency.

RESULTS

Participants with high sleep efficiency benefited more from written naming/spelling therapy than participants with low sleep efficiency in learning therapy materials (trained words). There was no effect of sleep efficiency in generalization of therapy materials to untrained words. Among participants with high sleep efficiency, those who received tDCS benefitted more from therapy than those who received sham condition. There was no additional benefit from tDCS in participants with low sleep efficiency.

CONCLUSION

Sleep efficiency modified the effects of language therapy and tDCS on language in participants with PPA. These results suggest sleep is a determinant of neuromodulation effects.Clinical Trial: tDCS Intervention in Primary Progressive Aphasia https://clinicaltrials.gov/ct2/show/NCT02606422.

Chronic Sleep Deprivation Blocks Voluntary Morphine Consumption but Not Conditioned Place Preference in Mice

The opioid epidemic remains a significant healthcare problem and is attributable to over 100,000 deaths per year. Poor sleep increases sensitivity to pain, impulsivity, inattention, and negative affect, all of which might perpetuate drug use. Opioid users have disrupted sleep during drug use and withdrawal and report poor sleep as a reason for relapse. However, preclinical studies investigating the relationship between sleep loss and substance use and the associated underlying neurobiological mechanisms of potential interactions are lacking. One of the most common forms of sleep loss in modern society is chronic short sleep (CSS) (<7 h/nightly for adults). Here, we used an established model of CSS to investigate the influence of disrupted sleep on opioid reward in male mice. The CSS paradigm did not increase corticosterone levels or depressive-like behavior after a single sleep deprivation session but did increase expression of Iba1, which typically reflects microglial activation, in the hypothalamus after 4 weeks of CSS. Rested control mice developed a morphine preference in a 2-bottle choice test, while mice exposed to CSS did not develop a morphine preference. Both groups demonstrated morphine conditioned place preference (mCPP), but there were no differences in conditioned preference between rested and CSS mice. Taken together, our results show that recovery sleep after chronic sleep disruption lessens voluntary opioid intake, without impacting conditioned reward associated with morphine.

Out-of-home placement, sleep problems, and later mental health and crime: A prospective investigation

Previous research suggests that out-of-home placement experiences increase the risk for mental health problems and criminal involvement. However, few studies have examined the mechanisms whereby out-of-home placement increases the risk for these outcomes. The present study examines whether sleep problems in part explain the relationship between childhood placement experiences and depression and anxiety and criminal arrests in adulthood. Data are from a prospective longitudinal study of 531 children with documented cases of childhood maltreatment (14% with no out-of-home placement, 68% placed solely for abuse and/or neglect, and 18% placed for maltreatment and delinquency) who were followed up into adulthood. Cases are from 1967 to 1971 from a metropolitan county in the Midwest. Sleep problems were assessed in young adulthood (M_age = 29 years). Depression and anxiety symptoms and arrest records were assessed in middle adulthood (M_age = 40 years). Structural equation modeling was used to test hypotheses. Both types of out-of-home placement experiences (for maltreatment only and for maltreatment and delinquency) predicted more sleep problems in adulthood across all models. Sleep problems in young adulthood predicted higher levels of anxiety and depression in middle adulthood, but not criminal arrests. Sleep problems mediated the relationship between placement only and internalizing symptoms and results differed for male, female, White, and Black individuals examined separately. Using court-substantiated cases of childhood abuse and neglect, this study demonstrates the long-term negative consequences of out-of-home placement experiences for sleep problems and anxiety and depression in adulthood. More attention is needed to insure adequate sleep for maltreated children. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Short Sleep Duration on the Night Before Surgery Is Associated With Postoperative Cognitive Decline in Elderly Patients: A Prospective Cohort Study

As the world is rapidly aging, and the number of elderly patients who undergo surgery is rising, postoperative cognitive decline among those patients has become an increasing healthcare problem. Although understanding the risk factors and mechanisms underlying the pathogenesis of postoperative cognitive decline is critically important from a preventative viewpoint, such knowledge and evidence are lacking. A growing body of evidence suggest an association between cognitive function and sleep duration. The purpose of this study was to investigate the association between postoperative cognitive function and sleep duration on the night before surgery using a wearable sleep tracker. In this 6-month prospective cohort study, we analyzed data from 194 patients aged ≥ 65 years who underwent elective non-cardiac and non-cranial surgery under general anesthesia. According to the sleep duration on the night before surgery, patients were categorized into following four groups: <5, 5–7, 7–9, and >9 h. Perioperative cognitive function and domains were assessed using a neuropsychological test battery, and the incidence and prevalence of cognitive decline over 6 months after surgery were analyzed using the multiple logistic regression analysis. During the 6-month follow-up period, 41 patients (21%) developed cognitive decline. The incidence of cognitive decline was significantly elevated for the patients with sleep duration < 5 h (vs. 7–9 h; surgical duration-adjusted odds ratio, 3.50; 95% confidence interval, 1.20–10.2; P < 0.05). The association between sleep duration and prevalence of cognitive decline was limited to the early postoperative period (at 1 week and 1 month). Among the cognitive domains assessed, attentional function was significantly impaired in patients with a sleep duration < 5 h [vs. 7–9 h at 1 week; 4/37 (10.8%) vs. 0/73 (0%); P < 0.05]. In conclusion, sleep duration < 5 h on the night before surgery was significantly associated with worse attentional function after surgery and higher incidence of cognitive decline. The present results indicate that sleep deprivation on the night before surgery may have a temporary but significantly negative influence on the patient's postoperative cognitive function and is a potential target for preventing cognitive decline.

Overnight Delta Dynamics Associated with Daytime Psychomotor Performance in Adults with Insomnia and Healthy Controls

PURPOSE

Sleep is vital to cognition, yet underlying mechanisms remain unclear. Although sleep duration and continuity are two well-established contributors, additional factors-including homeostatic sleep drive processes-may also underlie cognition-related sleep restoration. This study investigates the relative contributions of sleep EEG factors to psychomotor functioning in adults with insomnia and healthy controls (HC) to identify the most significant sleep factors supporting psychomotor functioning.

MATERIALS AND METHODS

Adults with insomnia (n = 37) and HC (n = 39) completed 3 nights of polysomnography and a complex psychomotor task (switching attention task; SAT). Univariate correlations identified the most significant predictors (traditional PSG, spectral EEG, initial delta peak, and overnight delta decline) of SAT performance, which were then entered into multivariable linear regressions examining whether predictors remained significant after accounting for shortened/fragmented sleep and whether relationships differed across groups.

RESULTS

In addition to greater wake after sleep onset (WASO; r = 0.33), a slower overnight delta decline (r = 0.50) and a lower initial delta peak (r = -0.38) were the most significant predictors of poorer SAT performance. Both overnight delta decline (F(7, 68) = 12.52, p < 0.001) and initial delta peak (F(7, 68) = 7.85, p = 0.007) remained significant predictors after controlling for demographics, total sleep time, and WASO. Relationships were analogous across subject groups.

CONCLUSION

Findings suggest that, in addition to sleep duration and continuity, processes related to recovery from and dissipation of homeostatic sleep drive may support psychomotor performance and broadly support daytime functioning in individuals with and without insomnia. Future research may examine overnight delta dynamics as transdiagnostic processes supporting cognition-related sleep restoration across a range of clinical populations.

Adolescent sleep health and school start times: Setting the research agenda for California and beyond: A research summit summary: A research summit summary

In fall 2019, California passed and signed into law SB328, the first US statewide legislation explicitly designed to protect adolescent sleep health by requiring most California public school districts to start no earlier than 8:00 AM for middle schools and 8:30 AM for high schools. Recognizing the unique opportunity presented by the bill's 3-year implementation period, a group of experts in adolescent sleep and school start times held a virtual summit on January 22-23, 2021 to (1) summarize the research on adolescent sleep and school start time change; (2) develop recommendations for relevant, refined, and innovative research areas and research questions; (3) provide input regarding research design, methodology, and implementation; and (4) offer a forum for networking, exchanging ideas, and establishing interdisciplinary research collaborations. Participants represented a multidisciplinary range of academic backgrounds including sleep and circadian biology, neuroscience, education, medicine, public health, mental health, safety, public policy, economics, implementation science, criminology, diversity studies, and science communication. This paper summarizes summit presentations regarding current knowledge on adolescent sleep health and school start times and key research recommendations from small group workshops on topics including research design and tools, methodological issues, sleep health disparities, logistical challenges in conducting school-based research, public-health impact, and novel and expanded approaches to research.

Impact of the first wave of COVID-19 pandemic on the Hungarian university students' social and health behaviour

BACKGROUND

The COVID-19 pandemic brought quick, severe and unexpected changes to our everyday life and also changed the traditional education pattern of Semmelweis University in the middle of academic year 2019-2020. We explored adaptive changes in Hungarian students' behaviour and their time-budget in order to determine whether quarantine and/or fear of infection were responsible for these changes.

METHODS

A self-administered online questionnaire was distributed to all students in the Hungarian language program (N = 7436) of Semmelweis University. Information was collected on basic demographic data, knowledge and attitude about COVID-19, methods of prevention as well as the students' behaviour before, during and after the first wave of the pandemic. Statistical analyses were processed using the IBM-SPSS 25.0 software package.

RESULTS

The overall response rate was 11% (N = 816). Only complete responses were processed (55%, N = 447). Among these responders, 83% did not fear the pandemic. Those who greatly feared COVID-19 infection strictly kept all regulations. The number of non-smokers increased by the end of the first wave. The nutrition of 100 students (21%) became healthier and the lockdown reduced the level of physical activity.

CONCLUSION

Social and health-related behaviour of medical students changed basically during the first wave of the pandemic and some changes remained after it in tobacco smoking, nutrition and sleeping habits. Time-budget of students changed significantly during the pandemic and did not return to the baseline values. Results of this study justify future multiple systematic research to analyse and better understand the short- and long-term effects of the current crisis.

An Ergogenic Medical Education: Building Curricula to Optimize Performance and Decrease Burnout

One of the most pervasive myths in our culture today is the belief that training increases performance. When, in fact, training decreases performance. The current structure of training programs and educational curriculums provide the evidence regarding the acceptance of this belief. Intense focus is placed on the quantity of training time with little regard for additional factors. In pursuit of excellence, maximizing training opportunity and learning exposure insists upon the sacrifice of recovery time. However, recovery is the necessary training period to increase performance. In athletics, training without recovery leads to overtraining syndrome. Burnout is the non-athletic equivalency seen in under-recovered learners and workers. As demonstrated by the climbing burnout rates, the current structure of educational programs, epitomized by medical residency, perpetuates the myth that more training equals better performance. The purpose of the article does not revolve around the presentation of novel research discoveries, but it insists upon the implementation of previously established performance data in curricula development beyond athletics. The inflection and deflection points along the growth and adaptation curves can be explicitly utilized to meet the educational and professional standards set forth by educational institutions. When tracking performance as the metric, initial training stimuli creates a descending slope, e.g., "training decreases performance." The concept that training creates a negative deflection is a neglected concept in academics. By incorporating this feature into learning environments, training can transition from surviving training redundancy to thriving with an optimal work:recovery ratio.

Genetically predicted insomnia and lung cancer risk: a Mendelian randomization study

BACKGROUND

The relationship between insomnia and lung cancer is scanty. The Mendelian randomization approach provides the rationale for evaluating the potential causality between genetically-predicted insomnia and lung cancer risk.

METHODS

We extracted 148 insomnia-related single-nucleotide polymorphisms (SNPs) as instrumental variables (IVs) from published genome-wide association studies (GWASs). Summary data of individual-level genetic information of participants were obtained from the International Lung Cancer Consortium (ILCCO) (29,266 cases and 56,450 controls). MR analyses were performed using the inverse-variance-weighted approach, MR pleiotropy residual sum and outlier (MR-PRESSO) test, weighted median estimator, and MR-Egger regression. Sensitivity analyses were further performed using Egger intercept analysis, leave-one-out analysis, MR-PRESSO global test, and Cochran's Q test to verify the robustness of our findings.

RESULTS

The results of the MR analysis indicated an increased risk of lung cancer in insomnia patients (OR = 1.1671; 95% CI 1.0754-1.2666, p = 0.0002). The subgroup analyses showed increased risks of lung adenocarcinoma (OR = 1.1878; 95% CI 1.0594-1.3317, p = 0.0032) and squamous cell lung cancer (OR = 1.1595; 95% CI 1.0248-1.3119, p = 0.0188).

CONCLUSION

Our study indicated that insomnia is a causal risk factor in the development of lung cancer. Due to the lack of evidence on both the epidemiology and the mechanism level, more studies are needed to better elucidate the results of the study.

Melatonin Successfully Rescues the Hippocampal Molecular Machinery and Enhances Anti-oxidative Activity Following Early-Life Sleep Deprivation Injury

Early-life sleep deprivation (ESD) is a serious condition with severe cognitive sequelae. Considering hippocampus plays an essential role in cognitive regulation, the present study aims to determine whether melatonin, a neuroendocrine beard with significant anti-oxidative activity, would greatly depress the hippocampal oxidative stress, improves the molecular machinery, and consequently exerts the neuro-protective effects following ESD. Male weanling Wistar rats (postnatal day 21) were subjected to ESD for three weeks. During this period, the animals were administered normal saline or melatonin (10 mg/kg) via intraperitoneal injection between 09:00 and 09:30 daily. After three cycles of ESD, the animals were kept under normal sleep/wake cycle until they reached adulthood and were sacrificed. The results indicated that ESD causes long-term effects, such as impairment of ionic distribution, interruption of the expressions of neurotransmitters and receptors, decreases in the levels of several antioxidant enzymes, and impairment of several signaling pathways, which contribute to neuronal death in hippocampal regions. Melatonin administration during ESD prevented these effects. Quantitative evaluation of cells also revealed a higher number of neurons in the melatonin-treated animals when compared with the saline-treated animals. As the hippocampus is critical to cognitive activity, preserving or even improving the hippocampal molecular machinery by melatonin during ESD not only helps us to better understand the underlying mechanisms of ESD-induced neuronal dysfunction, but also the therapeutic use of melatonin to counteract ESD-induced neuronal deficiency.

β-adrenergic Receptor Activity in the Hippocampal Dentate Gyrus Participates in Spatial Learning and Memory Impairment in Sleep-deprived Rats

Sleep deprivation (SD) leads to cognitive impairment, especially hippocampus-dependent learning and memory (L&M). The hippocampal dentate gyrus (DG) is the key structure involved in spatial L&M while long-term potentiation (LTP) is an important cellular mechanism responsible for L&M. Physiological and behavioral evidences support the hypothesis that norepinephrine (NE) and β-adrenoceptors (β-AR) may play an important role in regulating L&M, including LTP. However, it is enigmatic how β-AR influences the LTP disruption or memory impairment under SD circumstances. In the present study, the rats were subjected to SD for 18 h per day for 21 consecutive days and cognitive capacity was assessed by the Morris water maze (MWM) test. We examined the extracellular concentration of NE in the DG using in vivo brain microdialysis and HPLC analysis. The amplitudes of field excitatory postsynaptic potential (fEPSP) were subsequently measured in the DG during MWM test in freely moving conscious rats. The extracellular concentrations of NE and fEPSP amplitudes in the DG were significantly increased during MWM test, while these responses were suppressed in SD rats. When fEPSP amplitudes in the DG were measured after local injection of isoproterenol (an agonist of β-AR), SD rats significantly alleviated the fEPSP impairment and rescued deficits of spatial L&M. In addition, the reduced expression of N-methyl-D-aspartate (NMDA) and α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptors in SD rats significantly increased by activation of β-AR by isoproterenol in the DG. In conclusion, we propose that β-adrenergic signaling can improve memory impairment in sleep-deficient rats by regulating synaptic efficiency and glutamatergic receptor expression.

Predictors of Changes in Sleep Duration in Dutch Primary Schoolchildren: the ChecKid Study

BACKGROUND

Healthy sleep duration is essential to health and well-being in childhood and later life. Unfortunately, recent evidence shows a decline in sleep duration among children. Although effective interventions promoting healthy sleep duration require insight into its predictors, data on these factors are scarce. This study therefore investigated (i) which individual (lifestyle), social and cultural factors, and living conditions and (ii) which changes in these factors might be associated with the changes in sleep duration of Dutch primary schoolchildren observed over time.

METHOD

Data from the ChecKid study was used, a dynamic cohort study among 4-13-year-old children living in the city of Zwolle, the Netherlands. Associations between changes in sleep duration and individual (lifestyle) factors (i.e., age, sex, physical activity behavior, sugar-sweetened beverage consumption, screen behavior), social and cultural factors (i.e., parental rules, ethnicity), and living conditions (i.e., parental education, presence of screens in the bedroom, household size) were analyzed using multivariable linear regression.

RESULTS

A total of 1180 children participated, aged 6.6 ± 1.4 years in 2009. Mean sleep duration decreased from 11.4 ± 0.5 h/night in 2009 to 11.0 ± 0.5 h/night in 2012. Older children, boys, children who used screens after dinner, children with greater computer/game console use, and children whose parents had low levels of education had a greater decrease in sleep duration.

CONCLUSIONS

This article reports on one of the first large, longitudinal cohort studies on predictors of child sleep duration. The results of the study can inform future interventions aimed at promoting healthy sleep in primary schoolchildren.

Effects of two nights of sleep deprivation on executive function and central and peripheral fatigue during maximal voluntary contraction lasting 60s

PURPOSEː: The current study aimed at assessing the effect of a trial of two nights of sleep deprivation (SDT) on mood, sleepiness, motivation and cognitive and motor performance. METHODSː: Thirty-six healthy young and physically active adult men (17 in the control group and 19 in the SDT group) completed a 48-h control or 48-h SDT. For the SDT, participants did not sleep for 48 h. Executive function (attention and inhibitory control) in the Go/No-Go and Stroop tests, mood, sleepiness, motivation, heart rate variability (HRV), motor performance in a hand grip strength test, and 60-s maximal isometric contraction (MVC-60 s) of knee extension were evaluated at 9-11 am on consecutive days 1, 2, and 3. RESULTS: One night of sleep deprivation increased sleepiness, decreased mood, motivation and motor endurance but did not affect executive function (as measured in the Stroop and Go/No-Go tests), the MVC for hand and leg knee extensor muscles, and peripheral motor fatigue in the leg MVC-60 s task. However, the central activation ratio (CAR) decreased significantly during the MVC-60 s. The SDT significantly contributed to the decrease in these functions. That is, the SDT reduced executive function (increased reaction time during Go/No-Go test), MVC of knee extension, and the CAR before and after the MVC-60 s. By contrast, the SDT did not increase CAR immediately after the MVC-60 s and did not decrease the rate of torque development (RTD). CONCLUSIONSː: The SDT significantly impaired mood, motivation and increased sleepiness and HRV, reduced MVC of knee extensor muscles (but not RTD) and motor performance during the MVC-60 s and worsened executive function (attention and inhibitory control) only during the Go/No-Go task. However, the SDT did not reduce hand grip strength and CAR immediately after the MVC-60 s of knee extensor muscles.

Acoustic enhancement of slow wave sleep on consecutive nights improves alertness and attention in chronically short sleepers

INTRODUCTION

Chronic sleep restriction has been linked to occupational errors and motor vehicle crashes. Enhancing slow wave sleep may alleviate some of the cognitive deficits associated with chronic sleep restriction. However, the extent to which acoustic stimulation of slow wave activity (SWA) may improve alertness and attention is not well established, particularly with respect to consecutive nights of exposure.

METHODS

Twenty-five healthy adults (32.9 ± 8.2 years; 16 female) who self-restricted their sleep during workdays participated in a randomized, double-blind, cross-over study. Participants wore an automated acoustic stimulation device for two consecutive nights. Acoustic tones (50 ms long) were delivered on the up-phase of the slow wave first and then at constant 1-s inter-tone-intervals once N3 was identified (STIM), until an arousal or shift to another sleep stage occurred, or at inaudible decibels during equivalent stimulation periods (SHAM). Subjective alertness/fatigue (KSS, Samn-Perelli) was assessed across both days, and objective measures of alertness (MSLT) and attention (PVT) were assessed after two nights of stimulation.

RESULTS

After one night of acoustic stimulation, increased slow wave energy was observed in 68% of participants, with an average significant increase of 17.7% (p = 0.01), while Night 2 was associated with a 22.2% increase in SWA (p = 0.08). SWE was highly stable across the two nights of STIM (ICC 0.93, p < 0.001), and around half (56%) of participants were consistently classified as responders (11/25) or non-responders (3/25). Daytime testing showed that participants felt more alert and awake following each night of acoustic stimulation (p < 0.05), with improved objective attention across the day following two nights of acoustic stimulation.

DISCUSSION

Consecutive nights of acoustic stimulation enhanced SWA on both nights, and improved next day alertness and attention. Given large individual differences, we highlight the need to examine both the long-term effects of stimulation, and to identify inter-individual differences in acoustic stimulation response. Our findings suggest that the use of an acoustic device to enhance slow wave sleep may alleviate some of the deficits in alertness and attention typically associated with sleep restriction.

Barriers to managing sleep disturbance in people with malignant brain tumours and their caregivers: a qualitative analysis of healthcare professionals' perception

PURPOSE

This study explores healthcare professionals (HCPs)' perception and current management of sleep disturbance (SD) in people with malignant brain tumours and their caregivers. We aimed to identify barriers to effective management of SD in neuro-oncology care.

METHODS

We conducted semi-structured interviews with 11 HCPs involved in neuro-oncology care. The study was underpinned by the Capability Opportunity Motivation-Behaviour (COM-B) model within the Behavioural Change Wheel (BCW) guiding topic selection for the exploration of underlying processes of HCPs' behaviours and care decisions for SD management. Data were analysed thematically using a framework synthesis, and subsequently mapped onto the BCW to identify barriers for effective management and recommend potential interventions.

RESULTS

We identified four themes: HCPs' clinical opinions about SD, the current practice of SD management in neuro-oncology clinics, gaps in the current practice, and suggested areas for improvements. HCPs perceived SD as a prevalent yet secondary issue of low priority in neuro-oncology care. SD was unrecognised, and inadequately managed in usual clinical settings. Interventional options included modifying the use of corticosteroids or prescribing sedatives. When mapped onto the BCW, themes identified main barriers as a lack of awareness among HCPs about SD warranting care, due to the absence of screening tools and limited knowledge and resources for therapeutic interventions.

CONCLUSIONS

Multidisciplinary HCPs need training in the routine use of appropriate sleep assessment tools, and access to clear management pathways. More professional resources are needed to educate staff in implementing appropriate interventions for people with malignant brain tumours who are experiencing SD.

Losing sleep over work scheduling? The relationship between work schedules and sleep quality for service sector workers

In the retail and food service sectors, work schedules change from day-to-day and week-to-week, often with little advance notice, posing a potential impediment to healthy sleep patterns. In this article, we use data from the Shift Project collected in 2018 and 2019 for a sample of over 16,000 hourly workers employed in the service sector to examine relationships between unstable and unpredictable work schedules and sleep quality. We extend prior research on shift work and sleep disruption, which has often focused on the health care sector, to the retail and food service sector, which comprises nearly 20 percent of jobs in the U.S. We find that the unstable and unpredictable schedules that are typical in the service sector are associated with poor sleep quality, difficulty falling asleep, waking during sleep, and waking up feeling tired. As a benchmark, we compare unstable and unpredictable work schedules with two well-known predictors of sleep quality - having a young child and working the night shift. The strength of the associations between most types of unstable and unpredictable work schedules and sleep quality are stronger than those of having a pre-school aged child or working a regular night shift. Chronic uncertainty about the timing of work shifts appears to have a pernicious influence on sleep quality, and, given its prevalence for low-wage workers, potentially contributes to stark health inequalities by socioeconomic status.

Selective suppression of rapid eye movement sleep increases next-day negative affect and amygdala responses to social exclusion

Healthy sleep, positive general affect, and the ability to regulate emotional experiences are fundamental for well-being. In contrast, various mental disorders are associated with altered rapid eye movement (REM) sleep, negative affect, and diminished emotion regulation abilities. However, the neural processes mediating the relationship between these different phenomena are still not fully understood. In the present study of 42 healthy volunteers, we investigated the effects of selective REM sleep suppression (REMS) on general affect, as well as on feelings of social exclusion, cognitive reappraisal (CRA) of emotions, and their neural underpinnings. Using functional magnetic resonance imaging we show that, on the morning following sleep suppression, REMS increases general negative affect, enhances amygdala responses and alters its functional connectivity with anterior cingulate cortex during passively experienced experimental social exclusion. However, we did not find effects of REMS on subjective emotional ratings in response to social exclusion, their regulation using CRA, nor on functional amygdala connectivity while participants employed CRA. Our study supports the notion that REM sleep is important for affective processes, but emphasizes the need for future research to systematically investigate how REMS impacts different domains of affective experience and their neural correlates, in both healthy and (sub-)clinical populations.

Chronic rhinosinusitis and progression of cognitive impairment in dementia

AIM

The relationship between chronic inflammatory disease and cognitive decline is still unclear, but there is increasing evidence to support the role of systemic inflammation. The aim of this study was to investigate if chronic rhinosinusitis (CRS) in dementia or mild cognitive impairment (MCI) is associated with the progression of cognitive decline.

MATERIAL AND METHODS

We retrospectively reviewed the data of patients who complained of memory impairment, and underwent brain magnetic resonance imaging (MRI) from January 2006 to April 2019. According to the Mini-Mental State Examination (MMSE) score, subjects (n=661) were divided into three groups: dementia (≤17), MCI (18-23), and normal (≥24). CRS was defined as a total score of greater than or equal to 4 according to the Lund-Mackay scoring system using brain MRI. Multiple logistic regression analyses estimated adjusted odds ratio (aOR) for the association between CRS and dementia or MCI. Among the subjects with follow-up MMSE (n=286), a repeated-measures ANOVA was used to assess the difference of changes in MMSE scores between the groups with and without CRS.

RESULTS

According to the initial MMSE score, there were 221 subjects with dementia, 195 with MCI, and 245 with normal results. CRS was not significantly associated with dementia (aOR=1.519, CI=0.909-2.538, P=0.111), while being suggestively associated with MCI (aOR=1.740, CI=1.041-2.906, P=0.034). The MMSE scores at follow-up decreased further in subjects with CRS than in those without CRS (P=0.009). Especially, in the initial dementia group, there was a significant between-group difference in the MMSE score from baseline to follow-up (13.6±4.3 to 11.1±6.3 in CRS group vs. 13.5±3.3 to 14.4±5.4 in no CRS group, P=0.002).

CONCLUSION

The result of the present study implies a potential association between CRS and progression of cognitive decline. Physicians should be aware of this possibility in patients with clinically diagnosed CRS.

The impact of reduced sleep on school related outcomes for typically developing children aged 11–19: A systematic review

This systematic literature review examines the relationship between restricted and reduced sleep and school performance, learning and cognitive functioning in typically developing adolescents. Correlational and experimental data were evaluated from 17 studies which included participants ranging from 11 to 19 years in studies from seven countries around the world. The review found that there is evidence that restricted and reduced sleep is negatively associated with school performance and cognitive outcomes, although the findings were mixed. Implications for psychologists working with schools are discussed. More research and evaluation is needed to establish how these factors relate to each other conclusively.

Work Shift and Circadian Rhythm as Risk Factors for Poor Sleep Quality in Public Workers from Murcia (Spain)

The purpose of this study was to determine the prevalence of sleep quality and to investigate variables predicting the risk of poor sleep quality in public workers from Murcia (Spain). A cross-sectional and prospective study was conducted from October 2013 to February 2016 in 476 public workers. The Pittsburgh Sleep Quality Index was used to measure the quality of sleep, and the reduced scale of the Horne and Österberg Morningness-Eveningness Questionnaire was applied to analyze the circadian typology. The predictive variables of self-reported poor sleep quality were identified by multivariate logistic regression. No significant differences were found according to sex in the overall sleep quality scores (5 ± 2.9 versus 5.1 ± 3, p = 0.650), but there were in the duration of sleep. Three percent of females slept <5 hours compared to 2% of men (p = 0.034). Fixed morning shifts (OR = 1.9, 95% CI 1.3-3.1; p = 0.007) and evening chronotypes (OR = 1.6, 95% CI 1.0-2.3; p = 0.017) were independent predictors of suffering from poor sleep quality. In conclusion, the frequency of self-reported poor sleep quality among public workers from Murcia was 37.4%. Being a public worker with a fixed morning shift and having an evening chronotype demonstrated to be associated with the quality of sleep.

The spleen mediates chronic sleep restriction-mediated enhancement of LPS-induced neuroinflammation, cognitive deficits, and anxiety-like behavior

Chronic sleep restriction promotes neuroinflammation and cognitive deficits in neurodegenerative and neurobehavioral diseases. The spleens of mice exposed to chronic and repeated psychological stress serve as a reservoir of inflammatory myeloid cells that are released into the blood and brain following secondary acute stress. Here, we tested whether chronic and repeated short-term sleep restriction (CRSR) would exacerbate lipopolysaccharide (LPS)-induced neuroinflammation, cognitive deficits, and anxiety-like behavior in a spleen-dependent manner. LPS was administered to aged mice 14 days after exposure to CRSR consisting of three cycles of 7 days of sleep restriction with 7-day intervals in between. CRSR increased plasma proinflammatory cytokine levels, blood-brain barrier permeability, hippocampal proinflammatory cytokine levels, and transition of microglia to the M1 phenotype 24 h after LPS treatment. This in turn led to cognitive deficits and anxiety-like behavior. Interestingly, removal of the spleen 14 days prior to CRSR abrogated the enhancement of LPS-induced increases in systemic inflammation, neuroinflammation, cognitive deficits, and anxiety-like behavior. These data indicate that the spleen was essential for CRSR-induced exacerbation of LPS-induced brain damage.