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Sleep & Breathing = Schlaf & Atmung Mar 2022We analyzed the association between bedtime smart device usage habits and accelerometer-measured sleep outcomes (total sleeping time, sleep efficiency, and wake after...
PURPOSE
We analyzed the association between bedtime smart device usage habits and accelerometer-measured sleep outcomes (total sleeping time, sleep efficiency, and wake after sleep onset) in Hong Kong children and adolescents aged 8-14.
METHODS
A total of 467 students in Hong Kong participated in this study from 2016 to 2017. They self-reported their bedtime smart device usage habits. The primary caregiver of each participant was also invited to complete a self-administered questionnaire about the family's social-economic status and bedtime smart device usage habits. An ActiGraph GT3X accelerometer was used to assess participants' 7-day sleep outcomes.
RESULTS
The mean age of the participants was 10.3 (SD 1.9), and 54% were girls. Among the participants, 27% (n = 139) used a smart device before sleep, and 33% (n = 170) kept the smart device on before sleep. In total, 27% (n = 128) placed the smart device within reach before sleep, 23% (n = 107) would wake up when notifications were received, and 25% (n = 117) immediately checked the device after being awakened by a notification. Multiple regression controlling for age, sex, socio-economic status, and other confounders showed that those who woke up after receiving a notification had a statistically longer sleeping time (19.7 min, 95% CI: 0.3, 39.1, p = 0.046), lower sleep efficiency (- 0.71%, 95% CI - 1.40, - 0.02, p = 0.04), and a longer wake after sleep onset (2.6 min, 95% CI: 0.1, 5.1, p = 0.045) than those who did not. Nonetheless, all primary caregivers' bedtime smart device habits were insignificantly associated with all sleep outcomes of their children.
CONCLUSION
Those who woke up after receiving smart device notifications had lower sleep efficiency and longer wake after sleep onset than those who did not, and they compensated for their sleep loss by lengthening their total sleep time.
Topics: Accelerometry; Adolescent; Child; Female; Hong Kong; Humans; Male; Sleep; Sleep Quality; Smartphone; Time Factors
PubMed: 33928485
DOI: 10.1007/s11325-021-02377-1 -
Sleep May 2022The cellular consequences of sleep loss are poorly characterized. In the pyramidal neurons of mouse frontal cortex, we found that mitochondria and secondary lysosomes...
The cellular consequences of sleep loss are poorly characterized. In the pyramidal neurons of mouse frontal cortex, we found that mitochondria and secondary lysosomes occupy a larger proportion of the cytoplasm after chronic sleep restriction compared to sleep, consistent with increased cellular burden due to extended wake. For each morphological parameter, the within-animal variance was high, suggesting that the effects of sleep and sleep loss vary greatly among neurons. However, the analysis was based on 4-5 mice/group and a single section/cell. Here, we applied serial block-face scanning electron microscopy to identify signatures of sleep and sleep loss in the Drosophila brain. Stacks of images were acquired and used to obtain full 3D reconstructions of the cytoplasm and nucleus of 263 Kenyon cells from adult flies collected after a night of sleep (S) or after 11 h (SD11) or 35 h (SD35) of sleep deprivation (9 flies/group). Relative to S flies, SD35 flies showed increased density of dark clusters of chromatin and Golgi apparata and a trend increase in the percent of cell volume occupied by mitochondria, consistent with increased need for energy and protein supply during extended wake. Logistic regression models could assign each neuron to the correct experimental group with good accuracy, but in each cell, nuclear and cytoplasmic changes were poorly correlated, and within-fly variance was substantial in all experimental groups. Together, these results support the presence of ultrastructural signatures of sleep and sleep loss but underscore the complexity of their effects at the single-cell level.
Topics: Animals; Diptera; Frontal Lobe; Mice; Sleep; Sleep Deprivation; Wakefulness
PubMed: 35554595
DOI: 10.1093/sleep/zsab235 -
Nature Jul 2023While sleeping, many vertebrate groups alternate between at least two sleep stages: rapid eye movement and slow wave sleep, in part characterized by wake-like and... (Comparative Study)
Comparative Study
While sleeping, many vertebrate groups alternate between at least two sleep stages: rapid eye movement and slow wave sleep, in part characterized by wake-like and synchronous brain activity, respectively. Here we delineate neural and behavioural correlates of two stages of sleep in octopuses, marine invertebrates that evolutionarily diverged from vertebrates roughly 550 million years ago (ref. ) and have independently evolved large brains and behavioural sophistication. 'Quiet' sleep in octopuses is rhythmically interrupted by approximately 60-s bouts of pronounced body movements and rapid changes in skin patterning and texture. We show that these bouts are homeostatically regulated, rapidly reversible and come with increased arousal threshold, representing a distinct 'active' sleep stage. Computational analysis of active sleep skin patterning reveals diverse dynamics through a set of patterns conserved across octopuses and strongly resembling those seen while awake. High-density electrophysiological recordings from the central brain reveal that the local field potential (LFP) activity during active sleep resembles that of waking. LFP activity differs across brain regions, with the strongest activity during active sleep seen in the superior frontal and vertical lobes, anatomically connected regions associated with learning and memory function. During quiet sleep, these regions are relatively silent but generate LFP oscillations resembling mammalian sleep spindles in frequency and duration. The range of similarities with vertebrates indicates that aspects of two-stage sleep in octopuses may represent convergent features of complex cognition.
Topics: Animals; Mammals; Octopodiformes; Sleep; Sleep, REM; Wakefulness; Integumentary System; Movement; Time Factors; Local Field Potential Measurement; Learning; Central Nervous System; Arousal
PubMed: 37380770
DOI: 10.1038/s41586-023-06203-4 -
Revista Brasileira de Enfermagem 2018To identify evidence available in the literature about sleep patterns of infants attending nurseries. (Review)
Review
OBJECTIVE
To identify evidence available in the literature about sleep patterns of infants attending nurseries.
METHOD
An integrative review of studies published in Portuguese, English or Spanish available in full text on LILACS, CINAHL, and PubMed databases. The following descriptors sono, lactente and creches or berçários (in Portuguese) and sleep, infant and childcare or nurseries were used for LILACS, CINAHL and Pubmed, respectively. Nine studies were selected and analyzed.
RESULTS
The main component explored in the studies about sleep pattern is the sleep position of the infants, due to its association with sudden infant death syndrome. The results pointed to the need to promote and develop written guidelines regarding behavioral practices to reduce the risk of this phenomenon.
CONCLUSION
Evidence has identified sleep issues, mainly regarding the sleep position of the infant and the environment where the infant sleeps, showing that it is critical to set routines and interventions to improve the quality of sleep care of infants attending nurseries.
Topics: Humans; Infant; Infant, Newborn; Nurseries, Infant; Sleep; Sleep Disorders, Circadian Rhythm
PubMed: 29412302
DOI: 10.1590/0034-7167-2016-0480 -
BMC Public Health Mar 2022Adolescents are recommended to get 8-10 h of sleep at night, yet more than 80% fail to obtain this goal. Energy drink (ED) consumption has been linked to later bedtime...
BACKGROUND
Adolescents are recommended to get 8-10 h of sleep at night, yet more than 80% fail to obtain this goal. Energy drink (ED) consumption has been linked to later bedtime in adolescents. Therefore, we aimed to investigate the potential association between ED consumption and sleep duration, and shuteye latency among adolescents in Norway.
METHODS
This study was based on data from 15- to 16-year-old adolescents living in Oppland County in 2017. In total, 1353 adolescents were included in the analysis. Multiple regression models were used to estimate the associations between the frequency of ED consumption with sleep duration, shuteye latency, and getting 8 h of sleep.
RESULTS
Forty-six point five percent of the adolescents reported sleeping more than 8 h at night. Those who reported ED consumption at any frequency had significantly shorter sleep duration than those who did not. On average, high consumers of ED (consuming ED ≥ 4 times a week) had 0.95 (95% CI: 0.61, 1.28) hours (i.e., 57 min) less sleep than those who never consumed ED. In addition, high consumers had more than 25 min (95% CI: 13.95, 36.92) longer shuteye period than those who never consumed ED.
CONCLUSION
Most ED consumers fail to obtain the recommended 8 h of sleep at night, which could be a consequence of shorter sleep duration and longer shuteye latency. We found a dose-response relationship between frequency of ED consumption and reduced sleep. Yet, the potential long-term effects of both ED consumption and insufficient sleep among adolescents remain unclear.
Topics: Adolescent; Cross-Sectional Studies; Energy Drinks; Humans; Sleep; Sleep Wake Disorders; Time Factors
PubMed: 35303832
DOI: 10.1186/s12889-022-12972-w -
Journal of Sleep Research Aug 2023Current evidence points to the importance of sleep for adolescent physical and mental health. To date, most studies have examined the association between sleep...
Current evidence points to the importance of sleep for adolescent physical and mental health. To date, most studies have examined the association between sleep duration/quality and health in adolescence. An emerging line of research suggests that regularity in the timing of sleep may also play an important role in well-being. To address this aspect of sleep, the present study investigated daily variability of sleep, quantified using the sleep regularity index (SRI), in 46 adolescents (M = 12.78 ± 1.07 years) and its association with depressive symptoms/mental health. Sleep was measured during a 6 month period (M = 133.11 ± 36.42 nights) using actigraphs to quantify SRI values calculated for school days, weekends and holidays. Depressive symptoms and general psychopathology were assessed at the beginning (baseline) and end (follow-up) of the actigraphy measurements. Sleep was most regular during school days and associated with a longer total sleep time, shorter sleep onset latency, and higher sleep efficiency. Moreover, a higher SRI on school days was associated with fewer depressive symptoms at follow-up, whereas higher SRI on weekends was associated with less overall psychopathology at follow-up. Furthermore, the change in overall psychopathology, but not depressive symptoms across the two assessments was correlated with sleep regularity index. Our results suggest that regular timing of sleep is associated with sleep that is of longer duration and higher quality and may be protective of adolescent mental health. Therefore, adolescents should be encouraged not only to get enough sleep, but also to retain regular sleeping patterns to promote well-being and mental health.
Topics: Humans; Adolescent; Sleep Duration; Mental Health; Sleep; Sleep Quality; Schools; Actigraphy
PubMed: 36852716
DOI: 10.1111/jsr.13865 -
Sleep Nov 2021Our thoughts alter our sleep, but the underlying mechanisms are still unknown. We propose that mental processes are active to a greater or lesser extent during sleep and...
Our thoughts alter our sleep, but the underlying mechanisms are still unknown. We propose that mental processes are active to a greater or lesser extent during sleep and that this degree of activation affects our sleep depth. We examined this notion by activating the concept of "relaxation" during sleep using relaxation-related words in 50 healthy participants. In support of our hypothesis, playing relaxing words during non-rapid eye movement sleep extended the time spent in slow-wave sleep, increased power in the slow-wave activity band after the word cue, and abolished an asymmetrical sleep depth during the word presentation period. In addition, participants reported a higher sleep quality and elevated subjective alertness. Our results support the notion that the activation of mental concepts during sleep can influence sleep depth. They provide a basis for interventions using targeted activations to promote sleep depth and sleep quality to foster well-being and health.
Topics: Electroencephalography; Humans; Sleep; Sleep Quality; Sleep, Slow-Wave
PubMed: 34115139
DOI: 10.1093/sleep/zsab148 -
Current Opinion in Neurobiology Jun 2017Sleep is a deeply conserved, yet fundamentally mysterious behavioral state. Knowledge of the circuitry of sleep-wake regulation is an essential step in understanding the... (Review)
Review
Sleep is a deeply conserved, yet fundamentally mysterious behavioral state. Knowledge of the circuitry of sleep-wake regulation is an essential step in understanding the physiology of the sleeping brain. Recent efforts in Drosophila have revealed new populations which impact sleep, as well as provided unprecedented mechanistic and electrophysiological detail of established sleep-regulating neurons. Multiple, distributed centers of sleep-wake circuitry exist in the fly, including the mushroom bodies, central complex and the circadian clock cells. Intriguingly, certain populations have been implicated in specific roles in homeostatic rebound sleep, occurring after sleep loss. In short, our knowledge of fly sleep circuitry advances towards a greater view of brain-wide connectivity and integration of the signals and correlates of the state of sleep.
Topics: Animals; Brain; Circadian Rhythm; Drosophila; Mushroom Bodies; Sleep; Wakefulness
PubMed: 28366532
DOI: 10.1016/j.conb.2017.03.004 -
The Journal of Neuroscience : the... Jun 2022Recent research revealed a surprisingly large range of cognitive operations to be preserved during sleep in humans. The new challenge is therefore to understand...
Recent research revealed a surprisingly large range of cognitive operations to be preserved during sleep in humans. The new challenge is therefore to understand functions and mechanisms of processes, which so far have been mainly investigated in awake subjects. The current study focuses on dynamic changes of brain oscillations and connectivity patterns in response to environmental stimulation during non-REM sleep. Our results indicate that aurally presented names were processed and neuronally differentiated across the wake-sleep spectrum. Simultaneously recorded EEG and MEG signals revealed two distinct clusters of oscillatory power increase in response to the stimuli: (1) vigilance state-independent θ synchronization occurring immediately after stimulus onset, followed by (2) sleep-specific α/σ synchronization peaking after stimulus offset. We discuss the possible role of θ, α, and σ oscillations during non-REM sleep, and work toward a unified theory of brain rhythms and their functions during sleep. Previous research has revealed (residual) capacity of the sleeping human brain to interact with the environment. How sensory processing is realized by the neural assemblies in different stages of sleep is however unclear. To tackle this question, we examined simultaneously recorded MEG and EEG data. We discuss the possible role of θ, α, and σ oscillations during non-REM sleep. In contrast to versatile θ band response that reflected early stimulus processing step, succeeding α and σ band activity was sensitive to the saliency of the incoming information, and contingent on the sleep stage. Our findings suggest that the specific reorganization of mechanisms involved in later stages of sensory processing takes place upon falling asleep.
Topics: Brain; Electroencephalography; Humans; Sleep; Sleep Stages; Wakefulness
PubMed: 35508383
DOI: 10.1523/JNEUROSCI.1889-21.2022 -
Prague Medical Report 2023Sleep hygiene is essential for the prevention of somatic and mental disorders, including the prevention of sleep disorders. However, it does not typically address... (Review)
Review
Sleep hygiene is essential for the prevention of somatic and mental disorders, including the prevention of sleep disorders. However, it does not typically address individual differences. The aim of this review is threefold: first, to outline the empirical evidence for particular components of sleep hygiene rules; second, to indicate the importance of individualized sleep hygiene application with regard to the varying degree of validity of sleep hygiene rules in the population; third, to highlight a new field of sleep hygiene, namely light hygiene. PubMed and Google Scholar were used to identify studies that were published between 2007 and 2022. A search was conducted for studies related to sleeping rules topics: sleep regularity, regular exercise, alcohol, caffeine, napping, relaxation and meditation, food intake and light exposure. In applying these sleep hygiene principles, it is essential to pay attention to individual variables such as age, genetic predisposition, health status, and substance (caffeine, alcohol) possible dependence.
Topics: Adult; Humans; Sleep Hygiene; Caffeine; Sleep; Sleep Wake Disorders; Exercise
PubMed: 38069641
DOI: 10.14712/23362936.2023.26