Cycle-dependent oscillations in sex hormones have an effect on sleep and cognition [59]. Also, Baker
Cycle-dependent oscillations in sex hormones impact sleep and cognition [59]. Moreover, Baker and Drivers [60] reported hormonal cycle-dependent alterations in sleep architecture in naturally cycling women. While males are much less subject to monthly hormonal fluctuations, melatonin [61] and cortisol [62] secretion are also affected by seasonal changes in men. In addition to these difficulties of our study protocol and our sample, studies examining light influences differ significantly relating to the applied display size and sort (e.g., LED or LCD screens and computers, e-book readers or tablets/smartphones), brightness and size. In addition, Chellappa [3] concludes that circadian photosensitivity is subject to interindividual variations, i.e., the response to artificial light inside the evening, including modifications of circadian parameters, varies largely across folks. An example for anClocks Sleep 2021,individual trait Compound 48/80 site accountable for the higher variance in light-susceptibility across people may be eye pigmentation, as one study reported stronger melatonin suppression in subjects with lighter eye colors (i.e., blue, green or light-brown iris compared to dark brown iris) [63]. Hence, we can not rule out that we included far more high- than low-responders or the other way around. In addition to general interindividual differences in sensitivity to light, it can be furthermore affected by age [28]. Younger adults showed a lot stronger lightinduced adjustments in circadian (i.e., endogenous melatonin secretion) and sleep parameters (i.e., frontal SWA), subjective sleepiness and focus in contrast to older adults. This might not have already been a problem regarding the present benefits, as our study sample consists of a very homogeneous age group, but rather a problem regarding comparability involving research investigating light exposure with subjects of different age groups. Future research ought to thus address this issue relating to basic interindividual and age-related differences in light-responsiveness to acquire much more insight in to the interaction amongst the day-to-day present artificial light consumption and our inner clock. four. Components and Strategies 4.1. Participants 33 wholesome male subjects (mean age: 21.70, normal deviation: 1.91, range: 185 years) had been recruited and examined in the University of Salzburg amongst October 2019 and Etiocholanolone custom synthesis December 2020. The present final results extend our already published preliminary information of a subset of 14 participants [64]. All subjects were no cost of medication, non-smokers and reported no history of drug abuse, night-shift functioning, neurological or psychiatric illness. Additional, they have been right-handed, showed no above typical caffeine consumption (i.e., three cups of coffee, or 1 energy drink every day) and weren’t intense chronotypes (defined as subjects with raw sum-scores below 31 or above 69) in line with the German version from the morningness-eveningness questionnaire [65]. For the whole study period sleep habits have been monitored with wrist actigraphy (Cambridge Neurotechnology Actiwatch, CamNTech Ltd., Cambridge, England) and sleep diaries (“morning/evening protocol”; adapted version of Saletu and colleagues [66]) to assure a typical sleep-wake cycle. Participants have been remunerated with either 100 Euros and 16 h naturally credit for participation in scientific research or with 50 Euros and 24 h not surprisingly credit. All participants offered written informed consent. The study was authorized by the regional ethics committee and performed in accordance together with the newest v.
