Partial Sleep Deprivation Research Articles

Restorative effects of probiotics on memory impairment in sleep-deprived mice

ABSTRACT Background Insufficient sleep is a serious public health epidemic in modern society, impairing memory and other cognitive functions. In this study, partial sleep deprivation (SD) was used to induce cognitive impairment in mice to determine the effects of probiotics on subsequent cognitive deficits. Methods Lactiplantibacillus plantarum Lp-115 (Lp-115), Lacticaseibacillus paracasei Lpc-37 (Lpc-37), Bifidobacterium animalis subsp. lactis 420 (B420) and their combination were administered to mice subjected to partial SD and compared with non-SD and SD vehicle groups. Mice were administered a daily oral gavage containing either 1 × 109 colony forming units (CFU) of single-strain, 1.5 × 109 CFU of multi-strain (5 × 108 CFU/strain), or vehicle for thirty days prior to and for nine days during a behavioural test paradigm. The novel object recognition (NOR) test, spontaneous alternation Y-maze (Y-maze), and the step-through passive avoidance (STPA) task were applied to evaluate learning and memory performance following partial SD. Results Partial SD had a significant impact on cognitive function in vehicle mice. Intervention with Lpc-37 significantly improved recognition memory deficits in the NOR test, spatial working memory deficits in the Y-maze, and contextual long-term memory impairments in the STPA task, in mice subjected to partial SD compared to the SD vehicle group. The multi-strain significantly improved recognition memory deficits in the NOR test and spatial working memory deficits in the Y-maze in mice subjected to partial SD compared to the SD vehicle group. Conclusions These findings demonstrate that Lpc-37 and the multi-strain may play a role in alleviating memory impairments and improve cognitive function in partially sleep-deprived mice.

The Effects of a 30-Minute Napping Opportunity after a Night of Partial Sleep Denied on Cognitive and Short-Term High-Intensity Performance and Mood States

Background: It is suggested that there is a relationship between a 30-minute napping opportunity after a night of partial sleep denied on cognitive and short-term high-intensity performance and mood states. Aim: The purpose of this study was to look at the effects of a 30-minute nap on cognitive and short-term high-intensity performance, as well as mood states, following a night of partial sleep deprivation. Methods: On a voluntary basis, 15 elite male athletes took part in the study. The study was carried out as a quantitative study using an experimental design with pre-test and post-test groups. After four weeks of training on five days a week, the athletes were given a 30-minute nap (laying down) between 13:00 and 15:00. The Pittsburgh sleep quality index, vertical jump test, and pulmonary function test were administered to the athletes who napped at 17:00. The Shapiro-Wilk Normality Test was used to determine the data's normality distribution. In accordance with the experimental model and research design, the differences between measurement results were determined using the paired samples t-test (paired samples t-test). The threshold for significance was set at p0.05. Results: Maximum anaerobic power (W), average anaerobic power (W), minimum anaerobic power (W), vertical jump (cm), FVC(L), FEV1(L), FEV1/FVC (%) and FEF25 of the athletes participating in the research. A significant difference was determined between -75(L/s) pre-test values and post-test values (p<0.05). Athletes' anaerobic power (W), average anaerobic power (W), minimum anaerobic power (W), vertical jump (cm), FVC(L), FEV1(L), and FEF25-75 (L/s) post-test The athletes' FEV1/FVC (percent) post-test values were higher than the pre-test values and lower than the pre-test values (p0.05). Conclusion: As a result, short nap sessions have anaerobic power. It has been demonstrated that it improves respiratory functions and vertical jump parameters. Keywords: Cognitive level, napping, mood, high-intensity performance.

Effects of partial sleep deprivation: A comparative assessment of young non-professional and professional taxi drivers

AimThis study aims to determine the effects of partial sleep deprivation (PSD) on driving performance of professional and young non-professional drivers. MethodsThe study included fifty participants (20 professional taxi drivers and 30 young non-professional drivers) driving the simulator-cab in three conditions. The first test session (TS1) was conducted after one night of PSD followed by the second test (TS2) after two consecutive nights of PSD. The driving performance metrics in two conditions of PSD (i.e., sleep duration = 4.25 ± 0.5 h) were compared with the baseline drive with no sleep loss. Sleep restriction was monitored using Actiwatch. Drivers subjectively self-reported their alertness using Karolinska Sleepiness Scale (KSS). Driving performance metrics and reaction time to emergency events were collected during each drive. ResultsA preliminary mixed-design ANOVA showed deterioration in driving performance of all drivers in terms of speed (p < 0.1), speed variability (p = 0.06), standard deviation in lateral positions (SDLP) (p < 0.001) and delayed reaction time (p < 0.05). Separate Mixed-Effects Generalized Linear Models for professional and non-professional drivers showed that speed variability, SDLP and reaction time increased from baseline during both the PSD tests, among both the driving groups. The speed variability, SDLP and reaction time of professional drivers differed significantly from other drivers under PSD conditions. Contrary to the existing belief, the professional drivers had significant decrements in driving performance due to PSD. ConclusionA critical and comparative analysis revealed that driving experience/skill of professional drivers does not improve their resistance to deteriorating effects of sleep loss.

Social jetlag and sleep debts are altered in different rosters of night shift work

Night and shift work are suspected to cause various adverse effects on health and sleep. Sleep deprivation through shift work is assumed to be compensated on free days. So far it is not clear how different shift systems and shift lengths affect sleep structure on work and free days. Especially working night shifts disrupts the circadian rhythm but also extended working hours (12h) might affect sleep characteristics. Hitherto, the magnitude of sleep debt, social jetlag, and Locomotor Inactivity During Sleep (LIDS) in different shift systems is unknown. Here, we investigated the impact of five different shift rosters on sleep in 129 industrial workers from Germany. Permanent night work with multiple shift systems with and without night shifts and with different shift lengths were compared. Wrist-activity was monitored over 28 days revealing sleep on- and offsets as well as LIDS as proxy for sleep quality. Overall, 3,865 sleep bouts comprising 22,310 hours of sleep were examined. The mean daily age-adjusted sleep duration (including naps) was 6:43h and did not differ between shift workers of different rosters. However, sleep duration on workdays was particularly low in rotational shift systems with 12h-shifts (5:00h), while overall sleep debt was highest. Shift workers showed a median absolute social jetlag of 3:03h, which differed considerably between shift types and rosters (p<0.0001). Permanent night workers had the highest social jetlag (5:08h) and latest mid-sleeps on workdays and free days. Sleep quality was reduced in permanent night shift workers compared with shift workers in other rosters and differed between daytime and nighttime sleep. Shift work leads to partial sleep deprivation, which particularly affects workers in 12h-shifts and permanent night shifts. Working these shifts resulted in higher sleep debts and larger absolute social jetlag whereas sleep quality was especially reduced in permanent night shift workers compared with shift workers of other rosters.

Predicting vigilance vulnerability during 1 and 2 weeks of sleep restriction with baseline performance metrics.

We attempted to predict vigilance performance in adolescents during partial sleep deprivation using task summary metrics and drift diffusion modelling measures (DDM) derived from baseline vigilance performance. In the Need for Sleep studies, 57 adolescents (age = 15-19 years) underwent two baseline nights of 9-h time-in-bed (TIB), followed by two cycles of weekday sleep-restricted nights (5-h or 6.5-h TIB) and weekend recovery nights (9-h TIB). Vigilance was assessed daily with the Psychomotor Vigilance Task (PVT), with the number of lapses (response times ≥ 500 ms) as the primary outcome measure. The two DDM predictors were drift rate, which quantifies the speed of information accumulation and determines how quickly an individual derives a decision response, and non-decision time range, which indicates within-subject variation in physical, non-cognitive responding, e.g. motor actions. In the first week of sleep curtailment, faster accumulation of lapses was significantly associated with more lapses at baseline (p = .02), but not the two baseline DDM metrics: drift and non-decision time range (p > .07). On the other hand, faster accumulation of lapses and greater increment in reaction time variability from the first to the second week of sleep restriction were associated with lower drift (p < .007) at baseline. Among adolescents, baseline PVT lapses can predict inter-individual differences in vigilance vulnerability during 1 week of sleep restriction on weekdays, while drift more consistently predicts vulnerability during more weeks of sleep curtailment. Effects of Napping in Sleep-Restricted Adolescents, clinicaltrials.gov, NCT02838095. The Cognitive and Metabolic Effects of Sleep Restriction in Adolescents (NFS4), clinicaltrials.gov, NCT03333512.

Sleep deprivation affects gait control

Different levels of sleep restriction affect human performance in multiple aspects. However, it is unclear how sleep deprivation affects gait control. We applied a paced gait paradigm that included subliminal rhythm changes to analyze the effects of different sleep restriction levels (acute, chronic and control) on performance. Acute sleep deprivation (one night) group exhibited impaired performance in the sensorimotor synchronization gait protocol, such as a decrease in the Period Error between the footfalls and the auditory stimulus as well as missing more frequently the auditory cues. The group with chronic sleep restriction also underperformed when compared to the control group with a tendency to a late footfall with respect to the RAC sound. Our results suggest that partial or total sleep deprivation leads to a decrease in the performance in the sensorimotor control of gait. The superior performance of the chronic sleep group when compared to the acute group suggests that there is a compensatory mechanism that helps to improve motor performance.

Acute Myocardial Infarction and Daylight Saving Time Transitions: Is There a Risk?

Available evidence on the risk of acute myocardial infarction (AMI) in the days after the spring daylight saving time (DST) transition suggests either a modest increase or no risk increase. Partial sleep deprivation and enhanced circadian clock misalignment have been implicated as the underlying mechanisms for increased AMI risk, probably via enhanced thrombo-inflammatory processes and activation of the sympathetic nervous system. Most of the studies, as we suggest as a perspective here, have used potentially inappropriate control periods, including the two post-transitional weeks, because adjustment after the spring DST transition lasts at least four weeks for all chronotypes and probably even beyond this period for late chronotypes. The most plausible conclusions, at the moment, for the risk of AMI after the spring DST transition are: (1) the risk is increased, (2) a relatively modest risk increase could be currently underestimated or in some studies undetected, (3) late chronotypes and/or individuals with high levels of social jetlag (a proxy for circadian clock misalignment) could be more affected by the phenomenon, and (4) underlying pathophysiological mechanisms should be further explored. As a significant part of world’s population continues to be affected by the biannual clock change, the question of increased AMI risk in the post-transitional period remains an intriguing public health issue.

RoWDI: rolling window detection of sleep intrusions in the awake brain using fMRI

Objective. Brief episodes of sleep can intrude into the awake human brain due to lack of sleep or fatigue—compromising the safety of critical daily tasks (i.e. driving). These intrusions can also introduce artefactual activity within functional magnetic resonance imaging (fMRI) experiments, prompting the need for an objective and effective method of removing them. Approach. We have developed a method to track sleep-like events in awake humans via rolling window detection of intrusions (RoWDI) of fMRI signal template. These events can then be used in voxel-wise event-related analysis of fMRI data. To test this approach, we generated a template of fMRI activity associated with transition to sleep via simultaneous fMRI and electroencephalogram (EEG) (N = 10). RoWDI was then used to identify sleep-like events in 20 individuals performing a cognitive task during fMRI after a night of partial sleep deprivation. This approach was further validated in an independent fMRI dataset (N = 56). Main results. Our method (RoWDI) was able to infer frequent sleep-like events during the cognitive task performed after sleep deprivation. The sleep-like events were associated with on average of 20% reduction in pupil size and prolonged response time. The blood-oxygen-level-dependent activity during the sleep-like events covered thalami-cortical regions, which although spatially distinct, co-existed with, task-related activity. These key findings were validated in the independent dataset. Significance. RoWDI can reliably detect spontaneous sleep-like events in the human brain. Thus, it may also be used as a tool to delineate and account for neural activity associated with wake-sleep transitions in both resting-state and task-related fMRI studies.

High neuroticism is associated with reduced negative affect following sleep deprivation

The aim was to investigate how neuroticism moderates the affective consequences of personalized mild-moderate partial sleep deprivation. A total of 52 healthy subjects aged 18–35 years completed the NEO PI-3 at baseline, before they completed an 11-day study protocol. After maintaining habitual sleep for seven days, the participants were asked to sleep 2 h less than their average sleep duration, the last three nights of the study protocol. Sleep patterns were observed using actigraphs and sleep diaries. The participants completed the PANAS questionnaire measuring positive and negative affect at 9 am (±90 min) at day 1, 4, 8 (habitual sleep), 9 and 11 (partial sleep deprived). We found that participants with higher scores on neuroticism experienced a decrease in negative affect following sleep deprivation. Participants with lower scores on neuroticism experienced an increase in negative affect after sleep deprivation. Positive affect was reduced following sleep deprivation, regardless of scores on neuroticism.

The Effect of Experimental Recuperative and Appetitive Post-lunch Nap Opportunities, With or Without Caffeine, on Mood and Reaction Time in Highly Trained Athletes.

Purpose: To investigate the effects of placebo (PLA), 20 min nap opportunity (N20), 5mg·kg−1 of caffeine (CAF), and their combination (CAF+N20) on sleepiness, mood and reaction-time after partial sleep deprivation (PSD; 04h30 of time in bed; study 1) or after normal sleep night (NSN; 08h30 of time in bed; study 2).Methods: Twenty-three highly trained athletes (study 1; 9 and study 2; 14) performed four test sessions (PLA, CAF, N20 and CAF+N20) in double-blind, counterbalanced and randomized order. Simple (SRT) and two-choice (2CRT) reaction time, subjective sleepiness (ESS) and mood state (POMS) were assessed twice, pre- and post-intervention.Results: SRT was lower (i.e., better performance) during CAF condition after PSD (pre: 336 ± 15 ms vs. post: 312 ± 9 ms; p < 0.001; d = 2.07; Δ% = 7.26) and NSN (pre: 350 ± 39 ms vs. post: 323 ± 32 ms; p < 0.001; d = 0.72; Δ% = 7.71) compared to pre-intervention. N20 decreased 2CRT after PSD (pre: 411 ± 13 ms vs. post: 366 ± 20 ms; p < 0.001; d = 2.89; Δ% = 10.81) and NSN (pre: 418 ± 29 ms vs. post: 375 ± 40 ms; p < 0.001; d = 1.23; Δ% = 10.23). Similarly, 2CRT was shorter during CAF+N20 sessions after PSD (pre: 406 ± 26 ms vs. post: 357 ± 17 ms; p < 0.001; d = 2.17; Δ% = 12.02) and after NSN (pre: 386 ± 33 ms vs. post: 352 ± 30 ms; p < 0.001; d = 1.09; Δ% = 8.68). After PSD, POMS score decreased after CAF (p < 0.001; d = 2.38; Δ% = 66.97) and CAF+N20 (p < 0.001; d = 1.68; Δ% = 46.68). However, after NSN, only N20 reduced POMS (p < 0.001; d = 1.05; Δ% = 78.65) and ESS (p < 0.01; d = 0.71; Δ% = 19.11).Conclusion: After PSD, all interventions reduced sleepiness and only CAF enhanced mood with or without napping. However, only N20 enhanced mood and reduced sleepiness after NSN. Caffeine ingestion enhanced SRT performance regardless of sleep deprivation. N20, with or without caffeine ingestion, enhanced 2CRT independently of sleep deprivation. This suggests a different mode of action of napping and caffeine on sleepiness, mood and reaction time.

Confinement, partial sleep deprivation and defined physical activity\u2013influence on cardiorespiratory regulation and capacity

IntroductionAdequate cardiorespiratory fitness is of utmost importance during spaceflight and should be assessable via moderate work rate intensities, e.g., using kinetics parameters. The combination of restricted sleep, and defined physical exercise during a 45-day simulated space mission is expected to slow heart rate (HR) kinetics without changes in oxygen uptake ({dot{text{V}}text{O}}_{{2}}) kinetics.MethodsOverall, 14 crew members (9 males, 5 females, 37 ± 7 yrs, 23.4 ± 3.5 kg m−2) simulated a 45-d-mission to an asteroid. During the mission, the sleep schedule included 5 nights of 5 h and 2 nights of 8 h sleep. The crew members were tested on a cycle ergometer, using pseudo-random binary sequences, changing between 30 and 80 W on day 8 before (MD-8), day 22 (MD22) and 42 (MD42) after the beginning and day 4 (MD + 4) following the end of the mission. Kinetics information was assessed using the maxima of cross-correlation functions (CCFmax). Higher CCFmax indicates faster responses.ResultsCCFmax(HR) was significantly (p = 0.008) slower at MD-8 (0.30 ± 0.06) compared with MD22 (0.36 ± 0.06), MD42 (0.38 ± 0.06) and MD + 4 (0.35 ± 0.06). Mean HR values during the different work rate steps were higher at MD-8 and MD + 4 compared to MD22 and MD42 (p < 0.001).DiscussionThe physical training during the mission accelerated HR kinetics, but had no impact on mean HR values post mission. Thus, HR kinetics seem to be sensitive to changes in cardiorespiratory fitness and may be a valuable parameter to monitor fitness. Kinetics and capacities adapt independently in response to confinement in combination with defined physical activity and sleep.

113 Effects of Sleep on Intrusive Symptoms and Emotion Reactivity in a Laboratory-Based Film Analogue Study

Abstract Introduction Recent literature highlights the need to focus on the impact of intrusive symptoms as a possible risk factor for the development and maintenance of PTSD. Cognitive and sleep models also contribute to the further understanding of intrusive symptoms. Further emotion work emphasizes that disgust is an emotion closely associated with the emergence of posttraumatic stress symptomology following traumatic events. Methods This study utilized a film eliciting disgust to examine the effects of acute sleep deprivation on the intensity of intrusive symptoms and emotion reactivity. Forty-nine college students were randomly assigned to sleep as usual or an acute sleep deprivation after watching a disturbing film. It was hypothesized that, relative to the control group, participants who were acutely sleep deprived would report higher frequency of intrusive symptoms and higher negative valence. Results Findings were partially consistent with hypotheses. There were no group or interaction effects on intrusive symptoms, although participants across both groups reported significant decreases in negative valence and intrusive symptoms across the study (F(1, 47) = 10.30, p &amp;lt; 0.01). There was a significant interaction effect between sleep group and self-reported negative valence, where individuals in the sleep deprived group reported significantly higher valence than individuals in the control group, despite significant decreases in negative valence over time (F(1, 48) = 7.869, p &amp;lt; 0.01). Conclusion Possible mechanisms that may contribute to the significant difference in valence may be due to higher order emotion regulation strategies that are compromised due to sleep loss. However, the significant decreases in negative valence and intrusive symptoms over time may be due to methodological factors or the type of sleep manipulation. Further work can address these challenges by using a larger sample size or examining the effects of chronic, partial sleep deprivation. Support (if any):

Partial and Total Sleep Deprivation Interferes With Neural Correlates of Consolidation of Fear Extinction Memory

Partial and Total Sleep Deprivation Interferes With Neural Correlates of Consolidation of Fear Extinction Memory

Sleep-deprived car-following: Indicators of rear-end crash potential

Safety assessment among sleep-deprived drivers is a challenging research area with only a few sleep-related studies investigating safety performance during car-following. Therefore, this study aimed to measure the effects of partial sleep deprivation on driver safety during car-following. Fifty healthy male drivers with no prior history of any sleep-related disorders, drove the driving simulator in three conditions of varying sleep duration: a baseline (no sleep deprivation), test session (TS1) after one night of PSD (sleep ≤4.5 h/night) and TS2 after two consecutive nights of PSD. The reduced sleep in PSD sessions was monitored using an Actiwatch. Karolinska Sleepiness Scale was used to indicate loss of alertness among drivers. Each drive included a car-following task to measure longitudinal safety indicators based on speed and headway management: normalized time exposed to critical gap (TECG’), safety critical time headway and speed variability with respect to leading vehicle’s speed (SPV). Crash potential index (CPI) was also determined from deceleration rate of drivers during car-following and was found correlated with other indicators. Therefore, to determine the aggregate influence of PSD on safety during car-following, CPI was modelled in terms of TECG, SPV, THW and other covariates. All safety metrics were modelled using generalized mixed effects regression models. The results showed that compared to the baseline drive, critical time headway decreased by 0.65 and 1.08 times whereas speed variability increased by 1.34 and 1.28 times during the TS1 and TS2, respectively, both indicating higher crash risk. However, decrease in TECG’ by 64 % and 56 % during TS1 and TS2, respectively indicate compensatory measures to avoid risks due to sleep loss. A fractional regression model of crash potential revealed that low time-headway and higher speed variability and high time exposed to critical gap (TECG’) significantly contribute to higher CPI values indicating higher safety risk. Other covariates such as sleep duration, professional driving experience and history of traffic violations were also associated with safety indicators and CPI, however no significant effects of age were noticed in the study. The study findings present the safety indicators sensitive to rear-end crashes specifically under PSD conditions, which can be used in designing collisions avoidance systems and strategies to improve overall traffic safety.

Sleep Deprivation Deteriorates Heart Rate Variability and Photoplethysmography.

IntroductionSleep deprivation has deleterious effects on cardiovascular health. Using wearable health trackers, non-invasive physiological signals, such as heart rate variability (HRV), photoplethysmography (PPG), and baroreflex sensitivity (BRS) can be analyzed for detection of the effects of partial sleep deprivation on cardiovascular responses.MethodsFifteen participants underwent 1 week of baseline recording (BSL, usual day activity and sleep) followed by 3 days with 3 h of sleep per night (SDP), followed by 1 week of recovery with sleep ad lib (RCV). HRV was recorded using an orthostatic test every morning [root mean square of the successive differences (RMSSD), power in the low-frequency (LF) and high-frequency (HF) bands, and normalized power nLF and nHF were computed]; PPG and polysomnography (PSG) were recorded overnight. Continuous blood pressure and psychomotor vigilance task were also recorded. A questionnaire of subjective fatigue, sleepiness, and mood states was filled regularly.ResultsRMSSD and HF decreased while nLF increased during SDP, indicating a decrease in parasympathetic activity and a potential increase in sympathetic activity. PPG parameters indicated a decrease in amplitude and duration of the waveforms of the systolic and diastolic periods, which is compatible with increases in sympathetic activity and vascular tone. PSG showed a rebound of sleep duration, efficiency, and deep sleep in RCV compared to BSL. BRS remained unchanged while vigilance decreased during SDP. Questionnaires showed an increased subjective fatigue and sleepiness during SDP.ConclusionHRV and PPG are two markers easily measured with wearable devices and modified by partial sleep deprivation, contradictory to BRS. Both markers showed a decrease in parasympathetic activity, known as detrimental to cardiovascular health.

EFFECT OF DIFFERENT TYPES OF SLEEP DEPRIVATION AND SLEEP RECOVERY ON SALIVARY PH

Background: Salivary pH can rise or fall influenced by intrinsic and extrinsic factors. Sleep deprivation is one example of intrinsic factors. Sleep deprivation causes a reduction in sleep time at a certain time. Purpose: Analyze the effect of different types of sleep deprivations and sleep recovery on salivary pH. Method: This study was experimental research with a post-test only with a control group design. Thirty white Wistar strain rats were randomly divided into 5 groups: healthy control group (KI), partial sleep deprivation (PSD/KII), total sleep deprivation (TSD/KIII), partial sleep deprivation, and continued sleep recovery (PSD+SR/KIV) and total sleep deprivation and continued sleep recovery (TSD+SR/KV). The treatment is carried out on a single platform method. Salivary pH was measured with the help of color-coded pH strips that were given grading after the completion of sleep deprivation induction. Result: The mean decrease in salivary pH was highest in the TSD group. One Way ANOVA test showed significant differences (p &lt;0.05) in the control group with PSD and TSD, the PSD group with PSD+SR, TSD group with PSD+SR and TSD+SR. Conclusion: Sleep deprivation is proven to reduce the pH of Saliva. Total sleep deprivation is a chronic condition that has the most influence on decreasing salivary pH. The effect of decreasing salivary pH due to sleep deprivation is proven to be overcome by sleep recovery.

Effects of partial sleep deprivation after prolonged exercise on metabolic responses and exercise performance on the following day.

[Purpose]We determined the effect of partial sleep deprivation (PSD) after an exercise session on exercise performance on the following morning.[Methods]Eleven male athletes performed either a normal sleep trial (CON) or a PSD trial. On the first day (day 1), all subjects performed an exercise session consisting of 90 min of running (at 75% ) followed by 100 drop jumps. Maximal strength (MVC) was evaluated before and after exercise. In the CON trial, the sleep duration was 23:00–7:00, while in the PSD trial, the sleep duration was shortened to 40% of the regular sleep duration. On the following morning (day 2), MVC, the metabolic responses during 20 min of running (at 75% ), and time to exhaustion (TTE) at 85% were evaluated.[Results]On day 2, neither the MVC nor during 20 min of running differed significantly between the two trials. However, the respiratory exchange ratio was significantly lower in the PSD trial than in the CON trial (p = 0.01). Moreover, the TTE was significantly shorter in the PSD trial than in the CON trial (p = 0.01).[Conclusion]A single night of PSD after an exercise session significantly decreased endurance performance without significantly changing muscle strength or cardiopulmonary response.

Neurobehavioral alterations in a mouse model of chronic partial sleep deprivation.

The night shift paradigm induces a state of chronic partial sleep deprivation (CPSD) and enhances the vulnerability to neuronal dysfunction. However, the specific neuronal impact of CPSD has not been thoroughly explored to date. In the current study, the night shift condition was mimicked in female Swiss albino mice. The classical sleep deprivation model, i.e., Modified Multiple Platform (MMP) method, was used for 8h/day from Monday to Friday with Saturday and Sunday as a weekend off for nine weeks. Following nine weeks of night shift schedule, their neurobehavioral profile and physiological parameters were assessed along with the activity of the mitochondrial complexes, oxidative stress, serotonin levels, and inflammatory markers in the brain. Mice showed an overall hyperactive behavioral profile including hyperlocomotion, aggression, and stereotyped behavior accompanied by decreased activity of mitochondrial enzymes and serotonin levels, increased oxidative stress and inflammatory markers in whole brain homogenates. Collectively, the study points towards the occurrence of a hyperactive behavioral profile akin to mania and psychosis as a potential consequence of CPSD.

Daily light exposure, sleep–wake cycle and attention in adolescents from different urban contexts

Objectiveto compare daily light exposure, activity-rest rhythm, sleep–wake cycle (SWC) and attention in Brazilian students living in different levels of urbanization. Methods115 adolescents (74 girls), aged 14–18 years (mean 15.5 ± 0.7 years), from the first years of high school have participated. The SWC was evaluated by actimetry and a Sleep Diary for 10 days. Besides, the “Health and Sleep” Questionnaire, the Morningness and Eveningness Scale for adolescents, the Pittsburgh Sleep Quality Index, and the Pediatric Daytime Sleepiness Scale were answered. Attention was assessed by a Continuous Performance Task. ResultsIn the less urbanized region, there were a greater exposure to light during the day accompanied by a higher proportion of morning-types and less occurrence of excessive daytime sleepiness. Otherwise, in the more urbanized region, adolescents showed a trend to sleep less in weekdays and presented more irregularity in sleep duration between weekdays and weekend, with 83 ± 15% of sleep efficiency, 01:04 ± 1:30 h of WASO and 7 ± 6.7 awakenings per night on the weekdays, suggestive of poor sleep quality. Despite of this, they showed better attentional performance: more correct responses (tonic and phasic alertness, and sustained attention) and less omissions (for all components). Regardless of the degree of urbanization, there was partial sleep deprivation, irregular sleep schedules and poor sleep quality in adolescents. ConclusionsThe daily light exposure and activity-rest profiles, SWC and attention in adolescents varied according to the degree of urbanization. Besides, the negative impacts of early school starting times leading to sleep deprivation, irregular sleep times and poor sleep quality were observed irrespective of the degree of urbanization, reinforcing that the early school starting time at morning is a strong temporal challenge for teenagers, having negative impacts on cognition and academic performance.

The Correlation of Sleep and Academic Performance

The essence of sleep is to keep life in balance, ensuring that energy used during day time will also be replenished by resting at night. However, when sleep is interrupted and unable to achieve a blissful rest, it may compromise the health and unfolding tasks that teenagers need to accomplish. Young adults need at least 8 to 10 hours of sleep. Thus, grade 12 Science, Technology, Engineering, Agriculture, and Mathematics (STEAM) students from Silliman University Senior High School in the Philippines answered the online questionnaire on sleep deprivation, which correlates with sleep with academic performance. For nearly eight hours, these respondents in school were swamped with several academic tasks even after class hours leaving so little time to sleep. While this study reveals that sleep deprivation may affect academic performance, the study obtains 95% confidence that respondents show a mean between 6.85 hours and 7.40 hours 6. This indicates the respondents may occasionally lack 1 to 2 hours of sleep from the required average of 8 to 10 hours of rest. Also, it illustrates no linear correlation between the number of hours of sleep and the general average. This further demonstrates that students can sacrifice a portion of their sleep to have their desired grades and be accustomed to the lack of sleep and difficult academic tasks. Aside from that, 17 respondents are not sleep deprived. At the same time, 70% have partial sleep deprivation where most of their time is spent studying for exams, doing school projects, using social media, and video gaming. The top three outcomes of sleep deprivation are exhaustion, fatigue, and pessimism and succeeded by health risks, as well as a decline in thinking. Thus, to minimize having debt in sleep is to have time management, establish a comfortable sleeping environment, and less time on social media. The study concludes that there is no correlation between sleep and academic performance.