People differ in their sleep-wake behavior. This individual difference is conceptualized in different aspects, such as wake up times, bed times, times of peak performance, as well as in morning affect. A total of 14,987 visitors of an exhibition in the LWL State Museum of Natural History, Münster (Germany), did the survey on chronotype and gave their consent that these data can be used for a sc...

In the present study, orexinergic cell bodies within the brains of rhythmic and arrhythmic circadian chronotypes from three species of African mole rat (Highveld mole rat-Cryptomys hottentotus pretoriae, Ansell's mole rat--Fukomys anselli and the Damaraland mole rat--Fukomys damarensis) were identified using immunohistochemistry for orexin-A. Immunopositive orexinergic (Orx+) cell bodies were s...

Abstract Shift work, an essential part of our 24/7 society, inevitably leads to displacement the habitual sleep period and thereby misalignment internal circadian timing system with rest–activity cycle environment. How interindividual differences in organization affect duration during rotating shift work is not fully understood. The objective this study was assess effect chronotype, type, their...

Based on the timing of their daily activities, humans can be classified into earliertimed Morning chronotypes ("morning larks"), later-timed Evening chronotypes ("evening owls"), or between-timed Intermediate chronotypes. In adults, the genetic effect accounts for 50% of the inter-individual variance in chronotype. Evening owls in particular have an elevated risk of health hazards, while mornin...

Humans show large inter-individual differences in organising their behaviour within the 24-h day-this is most obvious in their preferred timing of sleep and wakefulness. Sleep and wake times show a near-Gaussian distribution in a given population, with extreme early types waking up when extreme late types fall asleep. This distribution is predominantly based on differences in an individuals' ci...

Background: Lecture attendance is very critical in medical practice. Good sleep hygiene crucial for academic performance. Therefore, this research aimed to assess the relationship between daytime sleepiness and chronotype, skipping classroom.
 Methods: A cross-sectional study was conducted among Students Tabuk from April 2022 July 2022. Three hundred thirty-four students were randomly sele...

Sleep has strong links to the symptomology of fibromyalgia syndrome (FMS), a diffuse musculoskeletal pain disorder. Information about the involvement of the circadian clock is, however, sparse. In this study, 1548 individuals with FMS completed an online survey containing questions on demographics, stimulant consumption, sleep quality, well-being and subjective pain, chronotype (assessed by the...

Individual differences in morningness-eveningness preference may influence susceptibility and response to sleepiness. These differences could influence driving performance, but the influence of morningness-eveningness preference on driving behavior and accident risk has not been comprehensively studied. As morningness-eveningness preference is associated with personality characteristics, we als...

Circadian rhythms, among other factors, have been shown to regulate key physiological processes involved in athletic performance. Personal best performance of athletes in the evening was confirmed across different sports. Contrary to this view, we identified peak performance times in athletes to be different between human "larks" and "owls" (also called "morningness/eveningness types" or "chron...

BACKGROUND An individual's chronotype influences his or her physiological rhythms. Some studies have looked at the effect of time of day on the responses to exercise, but studies on the effect of long-term training are lacking. OBJECTIVE  To report the effects of an 8-week training period during the polar night in non-athletes of different chronotypes living at 70°N. DESIGN  In all, 10 morn...