PURPOSE: Insufficient and poor sleep patterns are common among adolescents worldwide. Up to now, the evidence on adolescent sleep has been mostly informed by country-specific studies that used different measures and age groups, making direct comparisons difficult. Cross-national data on adolescent sleep that could inform nations and international discussions are lacking. We examined the sleep patterns of adolescents across 24 countries and by gender, age, and affluence groups. METHODS: We obtained sleep data on 165,793 adolescents (mean age 13.5 years; 50.5% girls) in 24 European and North American countries from the recent cross-sectional Health Behaviour in School-aged Children surveys (2013-2014 and 2017-2018). For each country, we calculated the age-standardized mean in sleep duration, timing, and consistency and the proportions meeting sleep recommendations on school and nonschool days from self-reported bedtimes and wake times. We conducted stratified analyses by gender, age, and family affluence group. RESULTS: Adolescent sleep patterns varied cross-nationally. The average sleep duration ranged between 7:47 and 9:07 hours on school days and between 9:31 and 10:22 hours on nonschool days, and the proportion of adolescents meeting sleep recommendations ranged between 32% and 86% on school days and between 79% and 92% on nonschool days. Sleep patterns by gender and affluence groups were largely similar, but older adolescents slept less and went to bed later on school days than younger adolescents in all countries. CONCLUSIONS: The sleep patterns of adolescents vary across countries and sociodemographic groups. Insufficient sleep on school days is common in many countries. Public health and policy efforts to promote healthy adolescent sleep are encouraged.

• Klíčová slova
• Adolescents, Age disparities, Epidemiology, International surveys, Public Health, Sleep, Sleep patterns, Socioeconomic differences,
• MeSH
• chování mladistvých etnologie   psychologie   MeSH
• dítě MeSH
• lidé MeSH
• mladiství MeSH
• průřezové studie MeSH
• průzkumy a dotazníky MeSH
• psychický stres epidemiologie   MeSH
• školy MeSH
• socioekonomické faktory MeSH
• spánek fyziologie   MeSH
• spánková deprivace epidemiologie   MeSH
• společenská třída * MeSH
• srovnání kultur MeSH
• věkové faktory MeSH
• veřejné zdravotnictví MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mladiství MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Evropa epidemiologie   MeSH
• Spojené státy americké epidemiologie   MeSH

• Klíčová slova
• HOSPITAL PATIENTS *, SLEEP *,
• MeSH
• hospitalizovaní pacienti * MeSH
• lidé MeSH
• spánek * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

OBJECTIVE: Over the past decade, concurrent with increasing social media use (SMU), there has been a shift toward poorer sleep among adolescents in many countries. The purpose of this study was to examine the cross-national associations between adolescent SMU and sleep patterns, by comparing 4 different categories of SMU (nonactive, active, intense, and problematic use). DESIGN, SETTING, AND PARTICIPANTS: Data were from 86,542 adolescents in 18 European and North American countries that participated in the 2017/18 Health Behaviour in School-aged study. MEASUREMENTS: Mixed-effects linear regression models were used to examine cross-national associations between 4 SMU categories and adolescent sleep duration, bedtime and social jetlag derived from self-reported data. RESULTS: For all countries combined, nonactive SMU was associated with longer sleep, earlier bedtimes, and less social jetlag, compared to active SMU, although the differences were minor. By comparison, intense and problematic SMU were associated with less sleep and later bedtimes on both school and nonschool days, and greater social jetlag, compared to active SMU. While findings were relatively consistent between countries, some differences were observed, suggesting that the national and cultural context may be important in interpreting results. CONCLUSIONS: These findings suggest that both intense and problematic SMU are associated with poorer sleep patterns in adolescents across most countries. Further research is needed to identify effective policies, programs, and messaging to promote the healthy use of social media and prevent potential negative impacts on adolescent sleep.

• Klíčová slova
• Adolescents, HBSC, International survey, Sleep, Social media,
• MeSH
• dítě MeSH
• jet lag syndrom MeSH
• lidé MeSH
• mladiství MeSH
• školy MeSH
• sociální média * MeSH
• spánek MeSH
• Check Tag
• dítě MeSH
• lidé MeSH
• mladiství MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Severní Amerika MeSH

• MeSH
• dítě MeSH
• dospělí MeSH
• elektroencefalografie MeSH
• elektrookulografie MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• pohyby očí MeSH
• spánek REM MeSH
• spánek * MeSH
• spánková deprivace MeSH
• stadia spánku MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Although rapid eye movement (REM) sleep is often thought of as a singular state, it consists of two substates, phasic and tonic REM, defined by the presence (respectively absence) of bursts of rapid eye movements. These two substates have distinct EEG signatures and functional properties. However, whether they exhibit regional specificities remains unknown. Using intracranial EEG recordings from 31 patients, we analyzed expert-labeled segments from tonic and phasic REM and contrasted them with wakefulness segments. We assessed the spectral and connectivity content of these segments using Welch's method to estimate power spectral density and the phase locking value to assess functional connectivity. Overall, we found a widespread power gradient between low and high frequencies (p < 0.05, Cohen's d = 0.17 ± 0.20), with tonic REM being dominated by lower frequencies (p < 0.01, d = 0.18 ± 0.08), and phasic REM by higher frequencies (p < 0.01, d = 0.18 ± 0.19). However, some regions, such as the occipito-temporal areas as well as medial frontal regions, exhibit opposite trends. Connectivity was overall higher in all bands except in the low and high ripple frequency bands in most networks during tonic REM (p < 0.01, d = 0.08 ± 0.09) compared to phasic REM. Yet, functional connections involving the visual network were always stronger during phasic REM when compared to tonic REM. These findings highlight the spatiotemporal heterogeneity of REM sleep which is consistent with the concept of focal sleep in humans.

• Klíčová slova
• REM, connectivity, microstate, phasic REM, spectrum, tonic REM,
• MeSH
• bdění fyziologie   MeSH
• dospělí MeSH
• elektroencefalografie MeSH
• lidé středního věku MeSH
• lidé MeSH
• mozek * fyziologie   MeSH
• nervová síť * fyziologie   MeSH
• polysomnografie MeSH
• spánek REM * fyziologie   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

• MeSH
• dýchání * MeSH
• gestační stáří MeSH
• lidé MeSH
• novorozenec nedonošený fyziologie   MeSH
• novorozenec MeSH
• spánek fyziologie   MeSH
• syndromy spánkové apnoe patofyziologie   MeSH
• Check Tag
• lidé MeSH
• novorozenec MeSH
• Publikační typ
• časopisecké články MeSH

Personal well-being, including people's sleep characteristics, is affected by a variety of factors, one example of which is wide-ranging high-impact public events. In this study, we use a large sleep database obtained through a smartphone application for sleep tracking via anonymized time-sampled data to study the effect of two political events with a wide-ranging impact on people's sleep characteristics: the Brexit referendum in June 2016, and the presidential election of Donald Trump in November 2016 METHOD: Using Sleep as Android - an actigraphy-based sleep monitoring smartphone application - we collected 10.5 million geo-located sleep records from more than 69,000 users in Europe and North America. Population-based changes in sleep around each of these two events, in the United Kingdom and in the United States of America, were assessed using a non-parametric bootstrap test RESULTS: The analysis revealed a significant reduction by 16 min and 21 s in the mean sleep duration of British people in the night after the Brexit poll (p < 0.001). Similarly, the analysis of the US presidential election revealed a significant 12 min 49 s drop in the mean sleep duration during the night following the event, in comparison with the whole studied region (p < 0.001), and an increase by 5 min and 9 s in the subsequent night (p = 0.0328). Additional analysis comparing the election night to comparable days in preceding years revealed that the actual reduction in sleep length may have been even greater. There is also an increase in the proportion of subjects with very short sleep CONCLUSIONS: The results demonstrate a significant impact of two specific major political events on population sleep characteristics. Our results further underline the potential of mobile applications and informatics approaches in general to provide data that enable us to investigate fundamental physiological variables over time and location.

• Klíčová slova
• Brexit, Mobile applications, Political events, Sleep as android, Sleep monitoring, Sleep patterns, Trump,
• MeSH
• akcelerometrie MeSH
• lidé MeSH
• mobilní aplikace MeSH
• politika * MeSH
• spánek * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Spojené království MeSH
• Spojené státy americké MeSH

• MeSH
• bdění MeSH
• dýchání MeSH
• elektroencefalografie * MeSH
• lidé MeSH
• matematika MeSH
• metody MeSH
• poruchy spánku a bdění diagnóza   MeSH
• pozornost MeSH
• spánek REM MeSH
• spánek * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Rats were deprived of sleep by placing them for 36 hours in a slowly moving drum. After this procedure, during recovery sleep, the latency of onset of the first rhombencephalic - paradoxical sleep period decreased and the proportion of telencephalic/rhombencephalic - slow wave sleep reversed (during the first hour of recovery sleep). Repeated administration during the deprivation period of physostigmine (0,5 mg/kg i. p. in 30 min intervals 20-30 times) inducing in waking animals in EEG pattern close to that of rhombencephalic sleep, or atropine (1 mg/kg i. p. in 60 min intervals 10-15 times) evoking an activity resembling telencephalic sleep, did not change the above measures of recovery sleep. Pharmacologically induced sleep-like patterns did not substitute for the sleep the rats were deprived off.

• MeSH
• atropin farmakologie   MeSH
• fysostigmin farmakologie   MeSH
• krysa rodu Rattus MeSH
• spánek REM účinky léků   MeSH
• spánková deprivace * MeSH
• stadia spánku účinky léků   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• atropin MeSH
• fysostigmin MeSH

• MeSH
• čití, cítění MeSH
• elektroencefalografie * MeSH
• kojenec MeSH
• lidé MeSH
• spánek fyziologie   MeSH
• Check Tag
• kojenec MeSH
• lidé MeSH
• Publikační typ
• časopisecké články MeSH