Significant nocturnal wakefulness after sleep onset in metabolic dysfunction-associated steatotic liver disease.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a multisystemic disease with a multifactorial pathogenesis involving dietary, environmental, and genetic factors. Previous mouse models suggested that circadian misalignment may additionally influence its development as it influences metabolism in diverse organs including the liver. Further, data from sleep questionnaires proved sleep-wake disruption in patients with MASLD.

Thirty-Fifth Annual Meeting of the Society for Light Treatment and Biological Rhythms (SLTBR), 20 June-22 June, Prague, Czech Republic.

I am delighted to introduce this collection of abstracts from our recent 35th Annual SLTBR Meeting in Prague [...

The Circadian Brain and Cognition.

Circadian rhythms are inherent to living organisms from single cells to humans and operate on a genetically determined cycle of approximately 24 hours. These endogenous rhythms are aligned with the external light/dark cycle of the Earth's rotation and offer the advantage of anticipating environmental changes. Circadian rhythms act directly on human cognition and indirectly through their fundamental influence on sleep/wake cycles.

Metadata recommendations for light logging and dosimetry datasets.

Background: Light exposure significantly impacts human health, regulating our circadian clock, sleep-wake cycle and other physiological processes. With the emergence of wearable light loggers and dosimeters, research on real-world light exposure effects is growing. There is a critical need to standardize data collection and documentation across studies.

Sleep disturbances and psychological well-being among military medical doctors of the Swiss Armed Forces: study protocol, rationale and development of a cross-sectional and longitudinal interventional study.

Background: Compared to civilians and non-medical personnel, military medical doctors are at increased risk for sleep disturbances and impaired psychological well-being. Despite their responsibility and workload, no research has examined sleep disturbances and psychological well-being among the medical doctors (MDs) of the Swiss Armed Forces (SAF). Thus, the aims of the proposed study are (1) to conduct a cross-sectional study (labeled 'Survey-Study 1') of sleep disturbances and psychological well-being among MDs of the SAF; (2) to identify MDs who report sleep disturbances (insomnia severity index >8), along with low psychological well-being such as symptoms of depression, anxiety and stress, but also emotion regulation, concentration, social life, strengths and difficulties, and mental toughness both in the private/professional and military context and (3) to offer those MDs with sleep disturbances an evidence-based and standardized online interventional group program of cognitive behavioral therapy for insomnia (eCBTi) over a time lapse of 6 weeks (labeled 'Intervention-Study 2').

Psychiatric Characteristics, Symptoms of Insomnia and Depression, Emotion Regulation, and Social Activity among Swiss Medical Students.

: Almost by default, young adult students are at increased risk of suffering from mental health issues, and this holds particularly true for medical students. Indeed, compared to the general population and non-medical students, medical students report higher scores for symptoms of depression. For Swiss medical students, research on the associations between psychiatric characteristics and symptoms of depression and insomnia, including cognitive-emotional processes and social activity, has been lacking so far.

Regulation of pupil size in natural vision across the human lifespan.

Vision is mediated by light passing through the pupil, which changes in diameter from approximately 2 to 8 mm between bright and dark illumination. With age, mean pupil size declines. In laboratory experiments, factors affecting pupil size can be experimentally controlled.

Military Values, Military Virtues, and Vulnerable Narcissism among Cadets of the Swiss Armed Forces-Results of a Cross-Sectional Study.

: For military leaders, military values and virtues are important psychological prerequisites for successful leadership and for ethical and moral military behavior. However, research on predictors of military values and virtues is scarce. Given this background, we investigated whether Organizational Citizenship Behavior (OCB), resilience, and vulnerable narcissism might be favorably or unfavorably associated with military values and virtues, and whether vulnerable narcissism could moderate the association between the OCB-by-resilience-interaction, and military virtues.

Towards an evidence-based integrative lighting score: a proposed multi-level approach.

Human circadian clocks are synchronized daily with the external light-dark cycle and entrained to the 24-hour day. There is increasing evidence that a lack of synchronization and circadian entrainment can lead to adverse health effects. Beyond vision, light plays a critical role in modulating many so-called non-visual functions, including sleep-wake cycles, alertness, mood and endocrine functions.

Open-Source Python Module for the Analysis of Personalized Light Exposure Data from Wearable Light Loggers and Dosimeters.

Light exposure fundamentally influences human physiology and behavior, with light being the most important of the circadian system. Throughout the day, people are exposed to various scenes differing in light level, spectral composition and spatio-temporal properties. Personalized light exposure can be measured through wearable light loggers and dosimeters, including wrist-worn actimeters containing light sensors, yielding time series of an individual's light exposure.

Impact of one night of sleep restriction on sleepiness and cognitive function: A systematic review and meta-analysis.

Detrimental consequences of chronic sleep restriction on cognitive function are well established in the literature. However, effects of a single night of sleep restriction remain equivocal. Therefore, we synthesized data from 44 studies to investigate effects of sleep restriction to 2-6 h sleep opportunity on sleepiness and cognition in this meta-analysis.

Inverse association between slow-wave sleep and low-grade inflammation in children and adolescents with major depressive disorder.

Objective: To investigate the relationship between both self-reported and objective sleep variables and low-grade inflammation in children and adolescents with major depressive disorder (MDD) of moderate to severe symptom severity.

Methods: In this cross-sectional study, we examined twenty-nine children and adolescents diagnosed with MDD and twenty-nine healthy controls (HC). Following a one-week actigraphy assessment, comprehensive sleep evaluations were conducted, including a one-night sleep EEG measurement and self-reported sleep data.

Associations between Sleep Disturbances, Personality Traits and Self-Regulation in a Sample of Healthy Adults.

Scientific evidence and everyday experience show that sleep disturbances and self-regulation as a proxy of stress reactivity are linked. Particular personality traits such as neuroticism, internalizing and externalizing problems are also associated with sleep disturbances. Here, we combined self-regulation and personality traits and associated these variables with subjective sleep disturbances.

Examining the structure validity of the Pittsburgh Sleep Quality Index among female workers during New Zealand's initial COVID-19 lockdown.

Sleep is important for good physical and mental health. The COVID-19 pandemic lockdown created a unique context that impacted psychological and social drivers for sleeping well. The Pittsburgh Sleep Quality Index (PSQI) is a widely used measurement tool assessing subjective sleep quality.

The sleep-circadian interface: A window into mental disorders.

Sleep, circadian rhythms, and mental health are reciprocally interlinked. Disruption to the quality, continuity, and timing of sleep can precipitate or exacerbate psychiatric symptoms in susceptible individuals, while treatments that target sleep-circadian disturbances can alleviate psychopathology. Conversely, psychiatric symptoms can reciprocally exacerbate poor sleep and disrupt clock-controlled processes.

Effects of calibrated blue-yellow changes in light on the human circadian clock.

Evening exposure to short-wavelength light can affect the circadian clock, sleep and alertness. Intrinsically photosensitive retinal ganglion cells expressing melanopsin are thought to be the primary drivers of these effects. Whether colour-sensitive cones also contribute is unclear.

An inventory of human light exposure behaviour.

Light exposure is an essential driver of health and well-being, and individual behaviours during rest and activity modulate physiologically relevant aspects of light exposure. Further understanding the behaviours that influence individual photic exposure patterns may provide insight into the volitional contributions to the physiological effects of light and guide behavioural points of intervention. Here, we present a novel, self-reported and psychometrically validated inventory to capture light exposure-related behaviour, the Light Exposure Behaviour Assessment (LEBA).

Seasonal Variation in the Responsiveness of the Melanopsin System to Evening Light: Why We Should Report Season When Collecting Data in Human Sleep and Circadian Studies.

It is well known that variations in light exposure during the day affect light sensitivity in the evening. More daylight reduces sensitivity, and less daylight increases it. On average days, we spend less time outdoors in winter and receive far less light than in summer.

Ultradian sleep cycles: Frequency, duration, and associations with individual and environmental factors-A retrospective study.

Objective: Sleep varies between individuals in response to sleep-wake history and various environmental factors, including light and noise. Here we report on the intranight variation of the ultradian nonrapid eye movement-rapid eye movement (NREM-REM) sleep cycle in 369 participants who have contributed to different laboratory studies from 1994 to 2020 at the Centre for Chronobiology, Basel, Switzerland.

Results: We observed a large interindividual variability in sleep cycle duration, including NREM and REM sleep episodes in healthy participants who were given an 8-hour sleep opportunity at habitual bedtime in controlled laboratory settings.

Utilising spectral lighting simulation technique for evaluating transmitted daylight through glazing: Exploring the non-visual effects and colour appearance.

Modern humans spend more time indoors than their ancestors. In indoor environments, windows are the primary building elements that provide access to daylight and views. The advancement of the building industry has introduced new glazing and coating technologies for windows.

34th Annual Meeting of the Society for Light Treatment and Biological Rhythms (SLTBR), 30 May-1 June, Lausanne, Switzerland.

The Society for Light Treatment and Biological Rhythms (SLTBR) held this year's annual meeting at the Ecole Polytechnique Fédérale (EPFL) in Lausanne, Switzerland from 30 May to 1 June in conjunction with the Day Light Academy (DLA) [...