A5032710515- Circadian rhythm and melatonin
- Sleep and related disorders
- Sleep and Wakefulness Research
- Impact of Light on Environment and Health
- Sleep and Work-Related Fatigue
- Building Energy and Comfort Optimization
- Spaceflight effects on biology
- Olfactory and Sensory Function Studies
- Dietary Effects on Health
- COVID-19 and Mental Health
- Photoreceptor and optogenetics research
- Birth, Development, and Health
- Optical Imaging and Spectroscopy Techniques
- EEG and Brain-Computer Interfaces
- Diet and metabolism studies
- Urban Heat Island Mitigation
- Health, Environment, Cognitive Aging
- Color perception and design
- Tryptophan and brain disorders
- Graph Labeling and Dimension Problems
- Advanced Graph Theory Research
- Dementia and Cognitive Impairment Research
- Retinal Development and Disorders
- Health and Wellbeing Research
- Urban Green Space and Health
University of Basel
2006-2025
Brigham and Women's Hospital
2007-2023
Harvard University
2007-2023
Circadian (United States)
2016-2023
University of Passau
2023
Massey University
2019-2022
École Polytechnique Fédérale de Lausanne
2009-2022
Universitäre Psychiatrische Kliniken Basel
2004-2022
Charité - Universitätsmedizin Berlin
2014-2019
Humboldt-Universität zu Berlin
2018-2019
Light can elicit acute physiological and alerting responses in humans, the magnitude of which depends on timing, intensity, duration light exposure. Here, we report that response as well its effects thermoregulation heart rate are also wavelength dependent. Exposure to 2 h monochromatic at 460 nm late evening induced a significantly greater melatonin suppression than occurred with 550-nm light, concomitant increased core body temperature (∼2.8 × 1013 photons/cm2/sec for each treatment)....
The circadian rhythms of melatonin and body temperature are set to an earlier hour in women than men, even when the men maintain nearly identical consistent bedtimes wake times. Moreover, tend up exhibit a greater preference for morning activities men. Although neurobiological mechanism underlying this sex difference alignment is unknown, multiple studies nonhuman animals have demonstrated period that could account such between Whether intrinsic humans underlies unknown. We analyzed precise...
Ocular light exposure has important influences on human health and well-being through modulation of circadian rhythms sleep, as well neuroendocrine cognitive functions. Prevailing patterns do not optimally engage these actions for many individuals, but advances in our understanding the underpinning mechanisms emerging lighting technologies now present opportunities to adjust promote optimal physical mental performance. A newly developed, international standard provides a SI-compliant way...
BACKGROUND. The circadian clock is a fundamental and pervasive biological program that coordinates 24-hour rhythms in physiology, metabolism, behavior, it essential to health. Whereas therapy adapted time of day increasingly reported be highly successful, needs personalized, since internal different for each individual. In addition, not stable trait, but influenced by many factors, including genetic predisposition, age, sex, environmental light levels, season. An easy convenient diagnostic...
Learning-dependent increases in sleep spindle density have been reported during nocturnal immediately after the learning session. Here, we investigated experience-dependent changes daytime EEG activity declarative of unrelated word pairs. At weekly intervals, 13 young male volunteers spent three 24 h sessions laboratory under carefully controlled homeostatic and circadian conditions. approximately midday, subjects performed either one two word-pair tasks or a matched nonlearning control...
Light strongly influences the circadian timing system in humans via non-image-forming photoreceptors retinal ganglion cells. Their spectral sensitivity is highest short-wavelength range of visible light spectrum as demonstrated by melatonin suppression, phase shifting, acute physiological responses, and subjective alertness. We tested impact short wavelength (460 nm) on sleep EEG power spectra architecture. hypothesized that its action similar magnitude to reported effects for polychromatic...
Summary Older adults have reduced sleep quality compared with younger when sleeping at habitual times and greater disruption their is adverse times. The purpose of this analysis was to investigate how subjective measures relate objectively recorded in older subjects scheduled all day. We analyzed data from 24 healthy (55–74 years) who took part a 32‐day inpatient study where polysomnography each night assessed after wake time. included baseline nights forced desynchrony (FD) protocol the...
Lighting conditions in workplaces contribute to a variety of factors related work satisfaction, productivity and well-being. We tested whether different photometric variables also influence visual perception the comfort lighting, as well subjective non-visual such mood, alertness Twenty-five young subjects spent two afternoons either under electric light or daylighting (without view from window). Subjects overall preferred for acceptance glare. Changes modulated changes perception, mood...
Daylight stems solely from direct, scattered and reflected sunlight, undergoes dynamic changes in irradiance spectral power composition due to latitude, time of day, year the nature physical environment (reflections, buildings vegetation). Humans their ancestors evolved under these natural day/night cycles over millions years. Electric light, a relatively recent invention, interacts competes with light–dark cycle impact human biology. What are consequences living industrialised urban areas...
Light, through its non-imaging forming effects, plays a dominant role on myriad of physiological functions, including the human sleep-wake cycle. The non-image effects light heavily rely specific properties such as intensity, duration, timing, pattern, and wavelengths. Here, we address how influence sleep wakefulness in humans acute e.g., alertness, and/or circadian timing system. Of critical relevance, discuss different characteristics exposure across 24-h day can lead to changes...
Light during the day and darkness at night are crucial factors for proper entrainment of human circadian system to solar 24-h day. However, modern life work styles have led much more time spent indoors, often with lower daytime higher evening/nighttime light intensity from electrical lighting than outdoors. Whether this has long-term consequences health is being currently investigated. We tested if bright blue-enriched morning over several days could counteract detrimental effects inadequate...
BackgroundThere is no consensus on reporting light characteristics in studies investigating non-visual responses to light. This project aimed develop a checklist for laboratory-based investigations the impact of physiology.MethodsA four-step modified Delphi process (three questionnaire-based feedback rounds and one face-to-face group discussion) involving international experts was conducted reach items be included checklist. Following process, resulting tested pilot phase with independent...
Abstract We developed a non‐invasive method to measure and quantify human circadian PER2 gene expression in oral mucosa samples show that this oscillates (= about day) fashion. also have the first evidence induction of is stimulated by exposing subjects 2 h light evening. This increase was statistically significant comparison non‐light control condition only after at 460 nm (blue) but not exposure 550 (green). Our results indicate non‐image‐forming visual system involved expression. The...
Abstract Sleep loss has marked and selective effects on brain wave activity during subsequent recovery sleep. The electroencephalogram (EEG) responds to sleep deprivation with a relative increase in power density the delta theta range non‐rapid eye movement We investigated age‐related changes of EEG response along antero‐posterior axis (Fz, Cz, Pz, Oz) under constant routine conditions. Both healthy young (20–31 years) older (57–74 participants manifested significant after 40 h deprivation,...
Subjective well-being largely depends on mood, which shows circadian rhythmicity and can be linked to rhythms in many physiological markers, such as melatonin cortisol. In healthy young volunteers mood is influenced by an interaction of phase the duration time awake. The authors analyzed this under differential sleep pressure conditions investigate age gender effects subjective well-being. Sixteen (8 women, 8 men; 20-35 years) 16 older 55-75 underwent a 40-h deprivation (high pressure) nap...
Purpose.: Nonvisual light-dependent functions in humans are conveyed mainly by intrinsically photosensitive retinal ganglion cells, which express melanopsin as photopigment. We aimed to identify the effects of circadian phase and sleepiness across 24 hours on various aspects pupil response light stimulation. Methods.: tested 10 healthy adults hourly two 12-hour sessions covering a 24-hour period. Pupil responses narrow bandwidth red (635 ± 18 nm) blue (463 (duration 1 30 seconds) at equal...
The risk of type 2 diabetes (T2D) is increased by abnormalities in sleep quantity and quality, circadian alignment, melatonin regulation. A common genetic variant a receptor for the circadian-regulated hormone (MTNR1B) associated with fasting blood glucose T2D, but whether or disruption mediates this unknown. We aimed to test if MTNR1B rs10830963 associates measures physiology intensive in-laboratory protocols (n = 58–96) cross-sectional studies quality timing from self-report 4,307–10,332),...
Abstract Circadian rhythms in physiology and behavior are modulated by external factors such as light or temperature. We studied whether self-selected office lighting during the habitual waking period had a different impact on alertness, cognitive performance hormonal secretion extreme morning evening chronotypes (N = 32), whose preferred bed- wake-up times differed several hours. The condition was compared with constant bright control dim light. Saliva samples for analyses, subjective...