ArticleLiterature Review

Cognitive consequences of sleep and sleep loss

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Abstract

Although we still lack any consensus function(s) for sleep, accumulating evidence suggests it plays an important role in homeostatic restoration, thermoregulation, tissue repair, immune control and memory processing. In the last decade an increasing number of reports continue to support a bidirectional and symbiotic relationship between sleep and memory. Studies using procedural and declarative learning tasks have demonstrated the need for sleep after learning in the offline consolidation of new memories. Furthermore, these consolidation benefits appear to be mediated by an overnight neural reorganization of memory that may result in a more efficient storage of information, affording improved next-day recall. Sleep before learning also appears to be critical for brain functioning. Specifically, one night of sleep deprivation markedly impairs hippocampal function, imposing a deficit in the ability to commit new experiences to memory. Taken together, these observations are of particular ecologic importance from a professional and education perspective when considering that sleep time continues to decrease across all age ranges throughout industrialized nations.

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... Several studies have confirmed this and shown that when sleep is deprived, memory encoding is disrupted [14]. Studies also suggest that an uninterrupted night of sleep prior to learning allows for more efficient retrieval of that information on subsequent occasions [15,16]. Sleep-dependent memory consolidation on the other hand involves the movement of information encoded during the waking day into permanent memory traces. ...
... This non-significant association between sleep and cognition contrasts with previous literature suggesting that healthy sleep promotes intact cognitive performance [16,60,61]. This discrepancy between our findings and those described by previously published studies may, as we note above, be a consequence of the GSAQ's limited ability to report accurately on sleep quality and its lack of sensitivity in detecting sub-clinical sleep disturbances. ...
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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.
... Changes in the thalamic and cortical systems as well as interactions between brain cells and neuron networks are what cause neuroplasticity. These findings mostly come from research done on cats [14], [15], and [3]. ...
... According to this study, memory function improved following a night of sleep. A pertinent theory was established, and it has recently advanced with the help of neurosciences, which provide scientific justification [3]. Infants have been the subject of studies on sleep-related learning. ...
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Numerous strategies have the potential to improve learning. Since memory is a fundamental cognitive skill that underpins learning, many approaches are employed in education to enhance it. If learning is a natural process, does this mean that there is a natural mechanism that supports learning? It is confirmed in this review that sleep is such a mechanism. According to the population's age, various effects of sleep on the brain and learning are supported by the research on this topic. For proper brain development and cognition, sleep is a crucial activity. In order to effectively exploit this knowledge and create fresh educational initiatives, additional studies need be conducted.
... It is well understood that sleep is critical for learning and memory Diekelmann and Born, 2010;Goel et al., 2009;Havekes et al., 2012;Killgore, 2010;Kim et al., 2022;Kreutzmann et al., 2015;Lim and Dinges, 2010;Walker, 2008;Walker and Stickgold, 2004;. SleepDep and heightened stress are known to independently impair cognitive function, and particularly learning and memory processes. ...
... Behavioral tasks designed to probe spatial navigation, contextual learning, object recognition, and fear memory are well-documented to rely on the consolidation of information in the hippocampus and extended limbic structures during sleep (Diekelmann and Born, 2010;Ferrara et al., 2012;Marshall and Born, 2007). Thus, it is noteworthy that hippocampal function is often impaired in response to both sleep loss and stress (Kim et al., 2015;Larosa and Wong, 2022;Prince and Abel, 2013;Prince et al., 2014;Walker, 2008). In fact, modest decreases in sleep or even mild disruptions in sleep, without effects on total sleep time, are sufficient to induce deficits in learning and disrupt hippocampal activity (Marks and Wayner, 2005;Van Der Werf et al., 2009). ...
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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.
... Circadian sleep disorders are also common in the elderly patients after surgery that appear to increase cardiovascular instability, adversely affect the immune system, increase metabolism, and prolong recovery time. These disorders are often associated with neuropsychiatric symptoms and allow the development of a common underlying pathological correlate [22]. Therefore, the use of melatonin seems to be reasonable among the various pharmacological agents [23][24][25][26]. ...
... Nevertheless, Y Wu et al. (2014) have shown that dysregulated melatonin levels correlate with postoperative delirium and support the hypothesis that sleep disorders are associated with postoperative delirium [27]. Synthetic melatonin supplements have been used to improve sleep quality [22]. It has also been shown that melatonin can improve sleep efficiency and total sleep time using polysomnography [28]. ...
Article
Background: Postoperative delirium is a common complication with a high morbidity rate. This study was designed to consider the effectiveness of melatonin in prevention and treatment of postoperative delirium. Methods: Seventy-two patients aged >60 years old with Abbreviated Mental Test (AMT) >8 scheduled for orthopedic surgery under spinal anesthesia, were randomly distributed equally to melatonin or placebo groups. In the melatonin group, the patients were given 5 mg melatonin capsules orally the night before surgery, the night of the operation, and two nights after the surgical operation at 9 pm. Likewise, in the placebo group, the patients received placebo in the same times. For diagnosis of postoperative delirium, the AMT test was used before the operation and three days after that. The Generalized estimating equations model (GEE) with logit link to Multivariate analysis was used in the study and P<0.05 was considered statistically significant. Results: In total, 72 patients completed the study. Thirty-three patients (45.8%) were male with a mean (SD) age 71.4 (3.6) years. On the first day after the surgery, the incidence of delirium was significantly lower in the melatonin group compared to the placebo group (22.2% vs. 44.4%, P=0.046). On the second and third days after the surgery, the level of delirium in the melatonin group was also significantly lower than that in the placebo one. The GEE model showed a significant interaction between time and treatment groups. Conclusion: The findings of the study showed that melatonin prevented delirium after the orthopedic surgeries in the elderly patients and could be useful for the patients as such.
... After investing countless hours in studying, testing, and clinical training that emphasizes standardized knowledge, practitioners may find it difficult to question whether this intensive preparation translates to optimal clinical outcomes. This bias extends to beliefs about sleep deprivation in medical training despite overwhelming evidence of its detrimental effects on performance [14][15][16][17][18][19][20][21][22]; those who have endured it often defend its necessity, perhaps as a way of validating their own experience. ...
... Sleep health, primarily insomnia and obstructive sleep apnea (OSA), should consistently be assessed when a patient presents with concerns of cognitive decline. Insomnia is associated with cognitive and affective symptoms, 43 and cognitive-behavioral treatment protocols for insomnia ameliorate cognitive sequelae. 44 Sleep apnea is a significant risk factor for multiple cardiovascular and cerebrovascular illnesses but is also associated with cognitive deficits, depression, and anxiety. ...
Article
Importance: When patients present with cognitive impairment, consults to neuropsychology can assist internists and psychiatrists in diagnosis, treatment planning, and determination of functional status. Neuropsychological evaluation and treatment have been shown to improve health outcomes and patient and family satisfaction. The objective of this narrative review is to explore the role of neuropsychologists in their collaboration with care teams to improve patient outcomes. Observations: Neuropsychologists have specialized education and training in brain behavior relationships and neurocognitive functioning. The consultation process for neuropsychology can be made more efficient by the referring physician clearly delineating the reason for the referral, ordering relevant laboratory tests and imaging studies, performing screenings for treatable conditions, and providing historical records to the neuropsychologist prior to the consult. Neuropsychological assessment can assist in diagnosis, identification of neuropsychological status, establishing a baseline, treatment planning, determination of functional ability, and monitoring the effectiveness of treatments. Conclusions and Relevance: Primary care teams and psychiatrists can benefit from collaboration with neuropsychologists. The most effective process for engaging neuropsychologists in the care of patients is through full communication, including properly placed consults. Prim Care Companion CNS Disord 2024;26(5):24nr03766. Author affiliations are listed at the end of this article.
... Our results reflect the positive impact that receiving treatment for sleep-disordered breathing has on specific elements of patients' quality of life. Generally, poor sleep quality is associated with cognitive [31][32][33], social [34], and emotional [32,34,35] impairement. Research in SDB populations have also found that patients demonstrate cognitive and emotional symptoms [36,37]. ...
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Background Previous research has suggested that alternative (respiratory) care providers (ACP) may provide affordable, accessible care for sleep-disordered breathing (SDB) that decreases wait-times and improves clinical outcomes. The objective of this study was to compare ACP-led and sleep physician-led care for SDB on patient reported outcome and experiences, with a focus on general and health-related quality of life, sleepiness, and patient satisfaction. Methods We conducted a secondary analysis of a randomized trial in which participants with severe SDB were assigned to either ACP-led or physician-led management. We created longitudinal linear mixed models to assess the impacts of treatment arm and timepoint on total and domain-level scores of multiple patient-reported outcome measures and patient-reported experience measures. Results Patients in both treatment arms (ACP-led n = 81; sleep-physician = 75) reported improved outcomes on the Sleep Apnea Quality of Life Index, Health Utilities Index, and Epworth Sleepiness Scale. Patients in each group had similar and clinically meaningful improvements on domains assessing cognition, emotion, and social functioning. The linear mixed models suggested no significant difference between treatment arms on the patient-reported outcomes. However, scores significantly improved over time. Conclusions Management of SDB using ACPs was comparable to physician-led care, as measured bypatient-reported outcome and experience measures. While loss to follow-up limits our findings, these results provide some support for the use of this novel health service delivery model to improve access to high quality SDB care. Clinical trial registration This is analysis of data from the study registered Clinicaltrials.gov (NCT02191085).
... It is a physiologically complex state that is essential for wellbeing, health, and even survival, as can be demonstrated by the ultimately lethal effects of sleep deprivation (Everson et al., 1989). Although yet to be fully clarified, sleep is known to be involved in childhood development (Roffwarg et al., 1966;Mirmiran et al., 1983;Zielinski et al., 2016), energy conservation (Benington and Heller, 1995;Scharf et al., 2008;Zielinski et al., 2016), immune modulation (Krueger, 2008;Zielinski and Krueger, 2011;Zielinski et al., 2016), cognitive and physical performance (Walker, 2008;Killgore, 2010;Zielinski et al., 2016;Watson, 2017;Cunha et al., 2023), psychological wellbeing (Scott et al., 2021), and clearance of brain waste (Xie et al., 2013;Zielinski et al., 2016). ...
Method
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Adequate sleep duration has recently been recognized as a major determinant of cardiovascular health by the American Heart Association. This is a significant step toward recognizing sleep as a major lifestyle factor and pillar of health, along with physical activity and nutrition. However, healthy sleep is not only a matter of duration. Other dimensions, such as timing, regularity, efficiency, satisfaction with sleep, and daytime alertness are also deemed important to consider. We have designed a systematic review protocol according to the PRISMA-P guidelines with the objective of determining which sleep dimensions are predictors of all-cause mortality and major adverse cardiovascular events (MACE; cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, and unstable angina requiring hospitalization), and whether or not the use of multiple dimensions of sleep yields superior predictive value to the use of sleep duration alone in predicting the above-mentioned outcomes. We will implement a systematic search strategy in 10 databases with independent manual screening by two reviewers. The aim is to comprehensively identify longitudinal studies which have examined the relationship between sleep duration and at least one other dimension of sleep and mortality or MACE. Meta-analysis will be performed after data extraction to address these objectives quantitatively. We anticipate that several sleep dimensions beyond sleep duration have been studied in relationship to all-cause mortality and MACE, and that a combination of multiple sleep dimensions can better predict these outcomes than sleep duration alone. Such findings would lay important groundwork to establish multidimensional sleep health as a major determinant of cardiovascular health.
... It results in chronic sleep deprivation, which has well-documented negative effects on cognitive function, particularly in the area of memory. Sleep plays a crucial role in the consolidation of short and long-term memories, and numerous studies have demonstrated that the feeling of a lack of adequate sleep can impair memory performance (Walker, 2008). One aspect of concern is how sleep disorders, such as insomnia, may contribute to the formation of false memories-instances where individuals recall events inaccurately. ...
... Given that sleep is essential for resource recovery (Chaudhuri et al., 2023), insomnia can inhibit this restorative process (Barnes et al., 2023). Consequently, sleep-deprived employees might remain in a state of resource scarcity (Opoku et al., 2023;Walker, 2008). It is reasonable to surmise that employees subjected to customer mistreatment may grapple with insomnia, with the stress exacerbating the sleep issues. ...
Article
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Purpose Grounded in the conservation of resources theory, this study proposes the mechanisms and conditions under which customer mistreatment affects employee proactive behavior. This study focuses on insomnia as a mediating mechanism and resilience as a boundary condition for the indirect effect of customer mistreatment on employee proactive behavior via insomnia. Design/methodology/approach We conducted a single survey in two phases, with a time lag of three weeks, among 302 frontline South Korean employees. The data collected from these two points were then analyzed using hierarchical regression analysis and the PROCESS macro. Findings The findings demonstrated that there was a significant negative relationship between customer mistreatment and employee proactive behavior, and this relationship was mediated by insomnia. Furthermore, the results revealed that resilience moderates both the effect of customer mistreatment on insomnia and the indirect effect of customer mistreatment on employee proactive behavior through insomnia. Research limitations/implications This research primarily focuses on Korean frontline workers, potentially limiting cultural generalizability. The reliance on self-reported data may introduce common method bias. Future studies should diversify participant demographics and utilize multi-source feedback to validate findings. Grounded in the Conservation of Resource Theory, this study underscores the neglected linkage between customer mistreatment and proactive behavior, especially in frontline employees. We introduce insomnia as a pivotal mediator, deepening our understanding of why mistreatment dampens proactivity. Additionally, we spotlight the role of resilience, revealing its buffering effect against mistreatment’s adverse outcomes. Practical implications Organizations should be aware of the detrimental effects of customer mistreatment on frontline employees, as it can hamper proactive behavior, primarily through the exacerbation of insomnia. Implementing resilience-training programs can be a proactive step, offering frontline staff tools to buffer against such negative outcomes. Managers are encouraged to recognize and address instances of customer mistreatment and prioritize employee well-being, which in turn can foster a more proactive and resilient workforce, enhancing organizational performance and customer satisfaction. Social implications This study underscores the broader societal challenge of customer mistreatment in the service sector, highlighting its ripple effects on employee well-being and proactive behavior. It sheds light on the importance of fostering respectful interactions in public and private spaces, emphasizing mutual respect between customers and service providers. Recognizing the adverse impacts of mistreatment can prompt societal discourse on workplace ethics and encourage organizations to advocate for their employees' rights. Ultimately, nurturing a culture that condemns customer mistreatment can lead to healthier work environments, benefitting both employees and society at large. Originality/value This study presents a novel approach by investigating the impact of customer mistreatment on employee proactive behavior, considering insomnia as a mediator, a perspective that has received limited attention in existing literature. Additionally, it introduces the concept of resilience as a moderator, offering fresh insights into how individual resilience levels can affect the relationship between customer mistreatment and proactive behavior. The research goes beyond traditional analyses of workplace dynamics to explore the broader implications of these interactions on personal well-being and sleep patterns. Through the application of a moderated-mediation framework, this study enhances understanding of complex organizational behavior dynamics, particularly in the service sector, and provides valuable implications for both theoretical understanding and practical application.
... The brain vital sign framework has since been validated increasingly in both health individuals as well as individuals with brain injury (including concussion) and brain disease (Ghosh Hajra et al., 2018;Fickling et al., 2019b, Smith et al., 2020Carrick et al., 2021;Fickling et al., 2021;Kirby et al., 2023). Sleep deprivation can lead to a wide decline across domains of cognitive performance, such as response speed, attention, memory, verbal comprehension, mood, et cetera (Pilcher and Huffcutt, 1996;Kim et al., 2001;Philibert, 2005;Walker, 2008). In this instance, both the P300 (basic attention) and the N400 (cognitive processing) responses represent potential indicators for cognitive impairment. ...
Article
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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.
... The enormous importance of sleep for human health, both physiological and mental, and for general well-being has been scientifically proven in numerous studies [1,2]. It is, therefore, essential to maintain a healthy sleep, and it is crucial to identify sleep disorders in time and initiate the appropriate treatment to achieve this. ...
Article
Healthy sleep is one of the prerequisites for a good human body and brain condition, including general well-being. Unfortunately, there are several sleep disorders that can negatively affect this. One of the most common is sleep apnoea, in which breathing is impaired. Studies have shown that this disorder often remains undiagnosed. To avoid this, developing a system that can be widely used in a home environment to detect apnoea and monitor the changes once therapy has been initiated is essential. The conceptualisation of such a system is the main aim of this research. After a thorough analysis of the available literature and state of the art in this area of knowledge, a concept of the system was created, which includes the following main components: data acquisition (including two parts), storage of the data, apnoea detection algorithm, user and device management, data visualisation. The modules are interchangeable, and interfaces have been defined for data transfer, most of which operate using the MQTT protocol. System diagrams and detailed component descriptions, including signal requirements and visualisation mockups, have also been developed. The system's design includes the necessary concepts for the implementation and can be realised in a prototype in the next phase.
... BP is one of the most common behaviours in young adults [2]. Severe BP can lead to sleep problems, such as insomnia and sleep deprivation [3], which can be detrimental to an individual's mental and physical health [4,5]. Given these potential deleterious sequelae, understanding the reasons behind BP is crucial to provide a direction for intervention. ...
Article
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This study aimed to investigate the relationships between depression and bedtime procrastination (BP), and the mediating effect of the brooding and perceived stress (PS). Based on the self-regulatory failure theory of procrastination in a temporal context and response styles theory, we constructed a chain mediation model. Total of 1136 participants (389 males and 747 females) completed the online questionnaire. In the present study, the participants were asked to fill The Beck Depression Inventory-II (BDI-II), Bedtime Procrastination Scale (BPS), Perceived Stress Scale (PSS) and Ruminative Responses Scale (RRS). The results showed that high level of depression positively affected brooding, and high level of brooding further positively affected PS, thus leading to BP. However, we did not find the mediating effect of brooding between depression and BP. This indicated that mood plays an important role in the mechanism of depression's effect on BP. The findings revealed pathways between depression and BP and was of great significance for the intervention of BP.
... Sleep plays a vital role in human life. Its influence on physical and psychological health and human well-being is enormous, which has already been demonstrated and underlined in numerous publications [1][2][3][4]. Accordingly, it is crucial to be able to analyse sleep to have the possibility to intervene in time in case of disorders, to eliminate them if possible, or at least to reduce their negative influence on health. ...
Article
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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.
... While it remains unclear whether fishes have sleep states comparable to those reported in other vertebrates, they nonetheless sleep (Blumberg et al., 2020;Leung et al., 2019;Ungurean et al., 2020). More generally, evidence in taxonomic groups as diverse as humans (Dawson and Reid, 1997;Van Dongen et al., 2003;Walker, 2008), birds (Aulsebrook et al., 2021;Johnsson et al., 2022) and bees (Klein et al., 2010), shows that sleep loss can impair performance when animals are awake. As such, modifications to sleep induced by fluoxetine exposure have the potential to influence a range of fitness-related traits, such as cognition in aquatic wildlife. ...
Article
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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.
... Roughly 30-40% of Americans report insomnia symptoms during a given year [3]. Getting proper sleep (i.e., sufficient quality and duration, as well as timing that matches the body's endogenous clock) is imperative as it is related to improvements in cerebral plasticity [4], memory, brain functioning, and physical restoration [5][6][7]. Later bedtime is associated with being overweight or obese, shorter sleep duration, and poorer eating behaviors in young adults [8,9]. Poor sleep during the last year [36]. ...
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(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.
... Critically, the goal was to inform students about how those systems generally work, but also how those systems interact with learning via memory systems. The central topic of interest was sleep, with a focus on the role of sleep in consolidating memories (Diekelmann et al., 2009;Marshall & Born, 2007;Walker & Stickgold, 2004) and the negative effects of sleep deprivation prior to learning (Feld & Diekelmann, 2015;Walker, 2008). Despite the critical role of sleep in memory and cognition, the combination of late adolescence physiology and the new autonomy found at college often result in students adopting maladaptive sleep schedules (Fernandez-Mendoza et al., 2010;Hagenauer & Lee, 2013;Lund et al., 2010). ...
Article
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.
... Background Sufficient sleep is crucial for individuals' functioning during the wake phase, and sleep disturbances may hamper health and performance [1][2][3][4][5][6][7]. The timing and duration of sleep are important determinants of individuals' affective state and behavior during the wake phase [3,[8][9][10][11]. ...
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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.
... While four studies found no significant effects of sleep on face recognition, two studies actually suggested that sleep after encoding or longer sleeping habits might impair subsequent face memory [81,94]. Although the majority of the selected studies found beneficial effects of sleep on face recognition performance, which is in agreement with the literature which demonstrates the importance of sleep for memory functioning and the damaging effects of sleep loss on memory [69,100], studies still varied considerably in various methodological aspects, which are important to highlight. ...
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Sleep has a major impact on a variety of human biological and cognitive functions. In particular, its impact on memory has attracted extensive research and has been amply demonstrated. However, it is still unclear whether sleep, or lack thereof, affects the ability to recognize faces. To clarify this, we conducted a scoping review on studies that included a face recognition memory task and any kind of sleep manipulation in adults without any sleep pathology. A systematic search and synthesis of peer-reviewed journal articles identified through the electronic databases Scopus, Web of Science, EBSCO, and PubMed was performed. A final sample of 18 articles, corresponding to 19 studies, met the eligibility criteria. The results of 13 articles suggested that sleep benefited face recognition ability, whereas two articles indicated a detrimental effect of sleep on performance, and four articles found no significant effects. This review highlights the high methodological variability between studies, in terms of sleep manipulation, retention interval, tasks used to probe face recognition, and other variables. In sum, although around one third of the studies show a beneficial effect of sleep on memory for faces, we suggest that future research should invest in replicating these findings with a stricter control of potentially confounding variables to allow stronger conclusions to be drawn.
... Importantly, β amyloid and tau protein are both implicated in the neuropathology of Alzheimer's Disease (AD), which is the number one cause of dementia. One night of sleep deprivation leads to impaired functioning of the hippocampus, which plays an essential role in forming and storing memories [84]. Therefore, SWS is important for both memory processing and learning [85]. ...
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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.
... Declines in sleep-dependent memory consolidation, episodic memory, and processing speed are related to declines in sleep duration [23][24][25][26][27][28][29]. Moreover, both over-sleeping or undersleeping are associated with declines in cognitive performance within the domains of executive functioning, attention, working memory, and flexibility [30][31][32][33]. ...
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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 to 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.
... This may be attributed to the higher cognitive demand required to undertake skill performance tasks [133]. Sleep loss has been shown to alter discrete cognitive functions, including reaction time [99,134], alertness [58], attention [134], memory [135], decision making [136,137] and learning [138]. Thus, physical tasks that are also cognitively demanding are likely to be most affected by acute sleep loss. ...
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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.
... Yoo et al. (2007) used functional magnetic resonance image (fMRI) to study sleep deprivation and found that lack of sleep inaptly regulated the emotional response in the brain to negative aversive stimuli. Walker (2008) found impairment in hippocampal functioning after one night of sleep deprivation, effecting the ability to form new memories. Using neuroimaging, Drummond et al. (2006) discovered that one night of sleep deprivation resulted in a decrease in blood flow to the prefrontal cortex, which corresponded with daytime deteriorations of prefrontal task performance. ...
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The current study investigated the relationship among sleep parameters, executive functioning, and behavioral problems in school-aged children. One hundred twenty school-age children (6-10 years old) participated in the week-long study. Children’s executive functioning was assessed using tasks that measure inhibition, set shifting, and updating. Parents completed a one-week sleep diary for their child, the Pediatric Sleep Questionnaire (PSQ), and the Child Behavioral Checklist (CBCL). Data were collected and multiple regression analyses were conducted to determine the relationships between sleep, executive function, and behavior problems. Daytime sleepiness predicted inhibition. Mediation analyses were used to examine whether executive functions (i.e., set shifting, inhibition, and updating) mediated the relationships between sleep parameters (i.e., sleep duration, sleep difficulties, daytime sleepiness, and sleep rhythmicity) and behavioral problems (i.e., externalizing and internalizing behaviors). Both daytime sleepiness and sleep difficulties predicted more externalizing and internalizing problems. Executive functions did not mediate the relationship between sleep variables and behavior problems. Exploratory analyses investigated the relationship between the individual sleep parameters, inattention, and behavior problems. Inattention mediated the relationship between daytime sleepiness and externalizing behaviors in children. The findings in this study demonstrate the importance of investigating individual sleep parameters as they relate to other factors, instead of aggregating sleep parameters into a total sleep problems score. Implications and future research directions were discussed.
... These consistent trends suggest the possibility that memantine deteriorates both working memory and daytime sleepiness in patients with PD-MCI. Several fMRI studies have reported that sleepiness is related to degrades of working memory performance [35,36]. Using resting state fMRI, Li et al. have reported that functional connectivity between the superior parietal lobule and right superior frontal gyrus (dorsolateral prefrontal cortex) of patients with primary insomnia was significantly poorer than that of the control group [37]. ...
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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.
Article
Sleep is important for youth athletes, supporting sport‐related recovery and performance, as well as growth and development. Sleep may be influenced by training factors; therefore, this study aimed to characterise youth athletes' sleep, and examine associations between training load, schedule and frequency, and sleep. Twenty‐six youth basketballers (age: 14.22 ± 0.74 years, 13 male, 13 female) from a high‐performance sporting school were monitored for a period of 8 weeks. Sleep measures (via actigraphy and sleep diaries) were collected alongside training diaries (recording time, duration and perceived exertion). Youth athletes who finished training after 20:30 hours had significantly less total sleep time than when training finished before 20:30 hours. Higher daily total training duration was associated with decreased total sleep time. There is a potential contradiction with findings related to the number of sessions per day, as participants who completed two training sessions in a day had more sleep than those who completed one session per day; but this was not observed for athletes with three sessions per day. Participants had large intra‐individual variations (mean intra‐individual standard deviation) in bedtime (1.06 hr) and sleep time (0.84 hr). In conclusion: (1) late night training sessions appear to reduce total sleep time and should be avoided in youth athletes; (2) total daily training duration had a greater negative effect on sleep than session frequency; and (3) participants’ large intra‐individual variation in bedtime may reduce sleep quality and efficiency.
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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.
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Despite evidence of the importance of sleep for cognitive performance, prior research finds limited effects of sleep disruptions on financial markets. This is puzzling because financial decisions rely on higher-order cognitive processes that are typically affected by sleep. We reconcile this dissonance by examining forecasts of corporate earnings by nonprofessional and professional forecasters. We find that nonprofessional forecasters exhibit a significant decline in their forecast accuracy following spring daylight saving time changes relative to professional forecasters. Using a separate sample of professional equity analysts’ forecasts, we continue to find that the information processing of analysts with less expertise is disproportionately negatively affected following sleep disruptions. Placebo tests provide support for sleep disruptions as the main driver of these effects. Overall, our evidence that information processing by less experienced and skilled market participants is particularly vulnerable to sleep disruptions provides one compelling reason why aggregate financial markets seem to be immune to sleep effects even though individual participants are not. This paper was accepted by Ranjani Krishnan, accounting. Supplemental Material: The internet appendix and data files are available at https://doi.org/10.1287/mnsc.2022.01102 .
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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.
Article
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.
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Objective Sleep problems are a significant risk factor for identifying and preventing suicidal involvement among adolescents. However, there is limited evidence to assess the underlying mechanisms between them. This study investigated the longitudinal relationship between sleep problems and suicidal behavior and examined whether this relationship was moderated by negative emotions, low self‐control, and nonsuicidal self‐injury (NSSI). Methods From December 2020 onward, we assessed 1214 Chinese secondary school adolescents (60.7% were boys, aged 13–19 years) three times, 6 months apart. Results In the direct effects model, sleep problems were found to have a positive impact on adolescent suicidal behavior. In the indirect effects model, we observed that sleep problems were associated with an elevated risk of suicidal behavior through several pathways: one‐mediator path of negative emotions, low self‐control, and NSSI, respectively; two‐mediator path of negative emotions via low self‐control, negative emotions via NSSI, and low self‐control via NSSI, and three‐mediator path from negative emotions to NSSI via low self‐control. Conclusions This longitudinal study provides evidence that sleep problems in adolescents may increase suicidal behavior by exacerbating negative emotions, weakening self‐control, and promoting NSSI. The findings suggest sleep problems should be addressed in suicide prevention and intervention efforts for adolescents.
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The influence of sleep on human health is enormous. Accordingly, sleep disorders can have a negative impact on it. To avoid this, they should be identified and treated in time. For this purpose, objective (with an appropriate device) or subjective (based on perceived values) measurement methods are used for sleep analysis to understand the problem. The aim of this work is to find out whether an exchange of the two methods is possible and can provide reliable results. In accordance with this goal, a study was conducted with people aged over 65 years old (a total of 154 night-time recordings) in which both measurement methods were compared. Sleep questionnaires and electronic devices for sleep assessment placed under the mattress were applied to achieve the study aims. The obtained results indicated that the correlation between both measurement methods could be observed for sleep characteristics such as total sleep time, total time in bed and sleep efficiency. However, there are also significant differences in absolute values of the two measurement approaches for some subjects/nights, which leads us to conclude that the substitution is more likely to be considered in case of long-term monitoring where the trends are of more importance and not the absolute values for individual nights.
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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.
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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.
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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.
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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.
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Aims and objectives: To analyze stress levels, sleep quality, sleepiness and chronotypes on emergency room (ER) professionals before and during the COVID-19. Background: ER healthcare professionals are exposed to high stress levels, and they often present with poor sleep quality. Design: Observational study conducted into two different phases (before the COVID-19 and during the first wave of the COVID-19). Method: Physicians, nurses and nursing assistants working in the ER were included. Stress, sleep quality, daytime sleepiness and chronotypes were assessed by the Stress Factors and Manifestations Scale (SFMS), the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS), and the Horne and Österberg Morningness-Eveningness questionnaire, respectively. The first phase of the study was performed between December 2019 and February 2020, and the second between April and June 2020. The STROBE checklist was used to report the present study. Results: In total, 189 ER professionals in the pre-COVID-19 phase and 171 (of the initial 189) during COVID-19 were included. The proportion of workers with a morning circadian rhythm increased during the COVID-19, and stress levels were significantly higher during COVID-19 compared to the previous phase (38.34 ± 10.74 vs. 49.97 ± 15.81). ER professionals with poor sleep quality presented higher stress in the pre-COVID-19 phase (40.60 ± 10.71 vs. 32.22 ± 8.19) and during COVID-19 (55.27 ± 15.75 vs. 39.66 ± 9.75). Similarly, workers with excessive sleepiness had higher stress in the pre-COVID-19 phase (42.06 ± 10.95 vs. 36.64 ± 10.24) and during COVID-19 (54.67 ± 18.10 vs. 48.44 ± 14.75). Positive associations were also found between the SFMS and the PSQI, as well as with the ESS in both phases of the study. Conclusions: Emergency room professionals had increased stress levels during the COVID-19 pandemic. Stress was particularly higher in those with poor sleep quality or with excessive daytime sleepiness. Relevance to clinical practice: These results should aim to impulse the implementation of measures to improve the working conditions of ER professionals.
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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.
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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. The two-way interaction between PTS symptoms and subjective sleep quality on cannabis use was not significant. 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 on weekly drinks 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 alcohol use among college students. Strategies for assessing and improving sleep quality and PTS symptoms can be incorporated into prevention and intervention efforts targeting alcohol related harm for college students.
Chapter
Behavioral pediatrics is a multidisciplinary field that involves many healthcare specialists revolving around the practicing pediatrician and primary care clinician; also, various additional, associated fields of training have developed such as developmental-behavioral pediatrics, neurodevelopmental pediatrics, pediatric psychodermatology and medical care for those of all ages with developmental disabilities (1-16). Experts in psychiatry and psychology work closely with pediatric clinicians in a variety of professional relationships, including co-located and non-co-located mental health settings (17-24). Pediatricians can provide a wide variety of care to children and adolescents with complex disorders, depending on their training as well as interests, and this book seeks to provide au courant perspectives in behavioral pediatrics (25-29). Behavioral health screening remains an important task of pediatricians and behavioral pediatricians as they evaluate their pediatric patients (30-40).
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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.
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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.
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Declarative memory consolidation is enhanced by sleep. In the investigation of underlying mechanisms, mainly rapid eye movement (REM) sleep and slow-wave sleep have been considered. More recently, sleep stage 2 with sleep spindles as a most prominent feature has received increasing attention. Specifically, in rats hippocampal ripples were found to occur in temporal proximity to cortical sleep spindles, indicating an information transfer between the hippocampus and neocortex, which is supposed to underlie the consolidation of declarative memories during sleep. This study in humans looks at the changes in EEG activity during nocturnal sleep after extensive training on a declarative learning task, as compared with a nonlearning control task of equal visual stimulation and subjectively rated cognitive strain. Time spent in each sleep stage, spindle density, and EEG power spectra for 28 electrode locations were determined. During sleep after training, the density of sleep spindles was significantly higher after the learning task as compared with the nonlearning control task. This effect was largest during the first 90 min of sleep (p < 0.01). Additionally, spindle density was correlated to recall performance both before and after sleep (r = 0.56; p < 0.05). Power spectra and time spent in sleep stages did not differ between learning and nonlearning conditions. Results indicate that spindle activity during non-REM sleep is sensitive to previous learning experience.
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Although the function of sleep remains elusive, several lines of evidence suggest that sleep has an important role in learning and memory. In light of the available data and with the prevalence of sleep deprivation (SD), we sought to determine the effect of SD on neuronal functioning. We found that the exposure of rats to 72 hr of primarily rapid eye movement SD impaired their subsequent performance on a hippocampus-dependent spatial learning task but had no effect on an amygdala-dependent learning task. To determine the underlying cellular level mechanisms of this hippocampal deficit, we examined the impact of SD on several fundamental aspects of membrane excitability and synaptic physiology in hippocampal CA1 pyramidal neurons and dentate gyrus granule cells. We found that neuronal excitability was severely reduced in CA1 neurons but not in granule cells and that the production of long-term potentiation of synaptic strength was inhibited in both areas. Using multiple SD methods we further attempted to differentiate the effects of sleep deprivation from those associated with the nonspecific stress induced by the sleep deprivation methods. Together these data suggest that failure to acquire adequate sleep produces several molecular and cellular level alterations that profoundly inhibit hippocampal functioning.
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The orphaned son of an Anglican clergyman, David Hartley (1705–57) was originally destined for holy orders. Declining to subscribe to the Thirty-Nine Articles, he turned to medicine and science yet remained a religious believer. This, his most significant work, provides a rigorous analysis of human nature, blending philosophy, psychology and theology. First published in two volumes in 1749, Observations on Man is notable for being based on the doctrine of the association of ideas. It greatly influenced scientists, theologians, social reformers and poets: Samuel Taylor Coleridge, who named his eldest son after Hartley, had his portrait painted while holding a copy. Volume 2 is particularly concerned with human morality and the duty and expectations of mankind. Here the author is keen to show that scientific observation is not necessarily in conflict with religious conviction.
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We reviewed the literature on sleep in psychiatric disorders and evaluated the data by meta-analysis, a statistical method designed to combine data from different studies. A total of 177 studies with data from 7151 patients and controls were reviewed. Most psychiatric groups showed significantly reduced sleep efficiency and total sleep time, accounted for by decrements in non-rapid eye movement sleep. Rapid eye movement sleep time was relatively preserved in all groups, and percentage of rapid eye movement sleep was increased in affective disorders. Reduction in rapid eye movement sleep latency was seen in affective disorders but occurred in other categories as well. Although no single sleep variable appeared to have absolute specificity for any particular psychiatric disorder, patterns of sleep disturbances associated with categories of psychiatric illnesses were observed. Overall, findings for patients with affective disorders differed most frequently and significantly from those for normal controls.
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Improvement in motor skill performance is known to continue for at least 24 hr following training, yet the relative contributions of time spent awake and asleep are unknown. Here we provide evidence that a night of sleep results in a 20% increase in motor speed without loss of accuracy, while an equivalent period of time during wake provides no significant benefit. Furthermore, a significant correlation exists between the improved performance overnight and the amount of stage 2 NREM sleep, particularly late in the night. This finding of sleep-dependent motor skill improvement may have important implications for the efficient learning of all skilled actions in humans.
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Practicing a motor skill triggers a process of memory consolidation that continues for hours after practice has ended, and becomes manifest in an improved skill at later testing. We used a sequential motor task (finger-to-thumb opposition task) to show that, in humans, the formation of motor skill memories essentially benefits from sleep. Independent of whether placed during daytime or nighttime, sleep after practice enhanced speed of sequence performance on average by 33.5% and reduced error rate by 30.1% as compared with corresponding intervals of wakefulness. The effect of sleep after learning proved to be stable when retesting was postponed for another night, to exclude effects of sleep loss and to assure that all subjects had sufficient sleep before retrieval testing. Also, the consolidating effect of sleep was specific for the motor sequence learned. It did not generalize to a similar sequence containing identical movement segments in a different order. Retention periods of wakefulness improved performance only moderately and only if placed during daytime. The observations demonstrate a critical role of sleep for storing and optimizing motor skills.
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While the functions of sleep remain largely unknown, one of the most exciting and contentious hypotheses is that sleep contributes importantly to memory. A large number of studies offer a substantive body of evidence supporting this role of sleep in what is becoming known as sleep-dependent memory processing. This review will provide evidence of sleep-dependent memory consolidation and sleep-dependent brain plasticity and is divided into five sections: (1) an overview of sleep stages, memory categories, and the distinct stages of memory development; (2) a review of the specific relationships between sleep and memory, both in humans and animals; (3) a survey of evidence describing sleep-dependent brain plasticity, including human brain imaging studies as well as animal studies of cellular neurophysiology and molecular biology. We close (4) with a consideration of unanswered questions as well as existing arguments against the role of sleep in learning and memory and (5) a concluding summary.
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Growing evidence indicates a role for sleep in off-line memory processing, specifically in post-training consolidation. In humans, sleep has been shown to trigger overnight learning on a motor-sequence memory task, while equivalent waking periods produce no such improvement. But while the behavioral characteristics of sleep-dependent motor learning become increasingly well characterized, the underlying neural basis remains unknown. Here we present functional magnetic resonance imaging data demonstrating a change in the representation of a motor memory after a night of sleep. Subjects trained on a motor-skill memory and 12 hours later, after either sleep or wake, were retested during functional magnetic resonance imaging. Following sleep relative to wake, regions of increased activation were expressed in the right primary motor cortex, medial prefrontal lobe, hippocampus and left cerebellum; changes that can support faster motor output and more precise mapping of key-press movements. In contrast, signal decreases were identified in parietal cortices, the left insular cortex, temporal pole and fronto-polar region, reflecting a reduced need for conscious spatial monitoring and a decreased emotional task burden. This evidence of an overnight, systems-level change in the representation of a motor memory holds important implications for acquiring real-life skills and in clinical rehabilitation following brain trauma, such as stroke.
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Although the functions of sleep remain largely unknown, one of the most exciting hypotheses is that sleep contributes importantly to processes of memory and brain plasticity. Over the past decade, a large body of work, spanning most of the neurosciences, has provided a substantive body of evidence supporting this role of sleep in what is becoming known as sleep-dependent memory processing. We review these findings, focusing specifically on the role of sleep in (a) memory encoding, (b) memory consolidation, (c) brain plasticity, and (d) memory reconsolidation; we finish with a summary of the field and its potential future directions.
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Evidence indicates that sleep after learning is critical for the subsequent consolidation of human memory. Whether sleep before learning is equally essential for the initial formation of new memories, however, remains an open question. We report that a single night of sleep deprivation produces a significant deficit in hippocampal activity during episodic memory encoding, resulting in worse subsequent retention. Furthermore, these hippocampal impairments instantiate a different pattern of functional connectivity in basic alertness networks of the brainstem and thalamus. We also find that unique prefrontal regions predict the success of encoding for sleep-deprived individuals relative to those who have slept normally. These results demonstrate that an absence of prior sleep substantially compromises the neural and behavioral capacity for committing new experiences to memory. It therefore appears that sleep before learning is critical in preparing the human brain for next-day memory formation-a worrying finding considering society's increasing erosion of sleep time.
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There is now compelling evidence that sleep promotes the long-term consolidation of declarative and procedural memories. Behavioral studies suggest that sleep preferentially consolidates explicit aspects of these memories, which during encoding are possibly associated with activation in prefrontal-hippocampal circuitry. Hippocampus-dependent declarative memory benefits particularly from slow-wave sleep (SWS), whereas rapid-eye-movement (REM) sleep seems to benefit procedural aspects of memory. Consolidation of hippocampus-dependent memories relies on a dialog between the neocortex and hippocampus. Crucial features of this dialog are the neuronal reactivation of new memories in the hippocampus during SWS, which stimulates the redistribution of memory representations to neocortical networks; and the neocortical slow (<1Hz) oscillation that synchronizes hippocampal-to-neocortical information transfer to activity in other brain structures.
Impact of sleep debt on metabolic and endocrine function
  • K Spiegel
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Spiegel K, Leproult R, Van Cauter E. Impact of sleep debt on metabolic and endocrine function. Lancet 1999;354(9188):1435−9.
Oblivescence during sleep and waking
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Impact of sleep debt on metabolic and endocrine function
  • Spiegel