How to quantify sleepiness during an attempt to sleep?

. Sleepiness assessment tools were mostly developed for detection of an elevated sleepiness level in the condition of sleep deprivation and several medical conditions. However, sleepiness occurs in various other conditions including the transition from wakefulness to sleep during an everyday attempt to get sleep.

The yin and yang of two opponent processes of sleep-wake regulation: Sex-associated differences in the spectral EEG markers of the drives for sleep and wake.

Although objectively measured characteristics of sleep efficiency and quality were found to be better in women than men, women more frequently than men suffer from poor or insufficient or non-restorative sleep. We explored this apparent paradox by testing the sex-associated differences in electroencephalographic (EEG) indicators of two opponent processes of sleep-wake regulation, the drives for sleep and wake. We tried to provide empirical support for the hypothesis that a stronger women's sleep drive can explain better objective characteristics of sleep quality in women than men, while a stronger women's wake drive can be an explanation of a higher frequency of sleep-related complaints in women than men.

[The effectiveness of suggestive techniques to improve sleep is enhanced by combining with sound stimulus based on binaural beats].

Objective: To test the hypothesis of the difference between 3 means of sleep latency (SL) during falling asleep: accompanied by audio stimulus embedded with binaural beats (BB); after listening to suggestive body relaxation instructions; accompanied by audio stimulus embedded with BB after listening to suggestive body relaxation instructions (that is the combination of 1 and 2).

Material And Methods: For the purpose of the study, a special Android application was developed and installed on the subjects' individual smartphones. The application assumed screen tapping test to control for fall-asleep process.

Evening chronotype, insufficient weekday sleep, and weekday-weekend gap in sleep times: What is really to blame for a reduction in self-perceived health among university students?

The association of insufficient sleep with reduced self-perceived health was previously well established. Moreover, it was sometimes shown that the indicators of poorer health were significantly related to chronotype and weekday-weekend gaps in sleep timing and duration. It remains to be elucidated, however, whether chronotype and these gaps can contribute to the reduced health self-ratings independently from shortened sleep duration or, alternatively, their relationship with health can be simply explained by their association with insufficient sleep on weekdays.

When early and late risers were left to their own devices: six distinct chronotypes under "lockdown" remained dissimilar on their sleep and health problems.

Under national "lockdown," the habitual late risers need not wake up early, and, similarly to the early risers, they don't lose much sleep on weekdays. We tested whether, despite a decrease in weekday sleep loss, the difference between distinct chronotypes in health and sleep problems persisted during "lockdown." Two online surveys were conducted from 10th to 20th of May, 2020 and 2021, one of them after 6 non-working weeks and another after 14 working weeks (during and after "lockdown," respectively).

[The effect of music embedded with binaural beats on heart rate parameters during nap].

Objective: To test hypothesis that music embedded with binaural beats can boost activity of parasympathetic part of autonomic nervous system (PPANS) with the development of nap.

Material And Methods: The power of high-frequency component of heart rate variability spectrum computed on successive 2-minute intervals during 20-minute nap was a comparison criterion. The criterion was compared during nap accompanied by music with embedded binaural beats (stimulus condition) and nap in silence (control condition).

Differences between male and female university students in sleepiness, weekday sleep loss, and weekend sleep duration.

Introduction: Women and men experience sleep differently and the difference in intrinsic desire for sleep might underlie some of the observed male-female differences. The objective of this cross-sectional questionnaire study of university students was to determine male-female differences in self-reported sleepiness and sleep-wake patterns.

Methods: Five questionnaires were completed by 1650 students at four Russian universities.

Differential relationship of two measures of sleepiness with the drives for sleep and wake.

Purpose: Since disagreement has been found between an objective sleep propensity measured by sleep onset latency (SOL) and subjective sleepiness assessment measured by the Epworth sleepiness scale (ESS) score, distinct underlying causes and consequences were suggested for these two sleepiness measures. We addressed the issue of validation of the ESS against objective sleepiness and sleep indexes by examining the hypothesis that these two sleepiness measures are disconnected due to their differential relationship with the antagonistic drives for sleep and wake.

Methods: The polysomnographic records of 50-min napping attempts were collected from 27 university students on three occasions.

[The effect of music containing binaural beats on daytime fall-asleep dynamics].

Aim: To test the hypothesis that listening to the music with the effect of binaural beats of theta and delta range during nap decreases sleep latency defined by 2 slow wave sleep stage appearance, as well as improves its stability.

Material And Methods: The experimental set of 20 min duration was established according to the counterbalanced scheme with 21 subjects. Each subject participated in two attempts: one attempt included sound stimulation (music) and another one was sham (silence).

[Vasoprotective effect of adaptation to hypoxia in myocardial ischemia and reperfusion injury].

Adaptation to hypoxia is known to be cardioprotective in ischemic and reperfusion (IR) injury of the myocardium. This study was focused on investigating a possibility for prevention of endothelial dysfunction in IR injury of the rat heart using adaptation to intermittent hypoxia, which was performed in a cyclic mode (5-10 min of hypoxia interspersed with 4 min of normoxia, 5-8 cycles daily) for 21 days. Endothelial function of coronary blood vessels was evaluated after the in vitro IR of isolated heart (15 min of ischemia and 10 min of reperfusion) by the increment of coronary flow rate in response to acetylcholine.