Sleep extension normalizes ERP of waking auditory sensory gating in healthy habitually short sleeping individuals.

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Gumenyuk, Valentina; Korzyukov, Oleg; Roth, Thomas; Bowyer, Susan M; Drake, Christopher L

2013-01-01

Chronic sleep loss has been associated with increased daytime sleepiness, as well as impairments in memory and attentional processes. In the present study, we evaluated the neuronal changes of a pre-attentive process of wake auditory sensory gating, measured by brain event-related potential (ERP)--P50 in eight normal sleepers (NS) (habitual total sleep time (TST) 7 h 32 m) vs. eight chronic short sleeping individuals (SS) (habitual TST ≤6 h). To evaluate the effect of sleep extension on sensory gating, the extended sleep condition was performed in chronic short sleeping individuals. Thus, one week of time in bed (6 h 11 m) corresponding to habitual short sleep (hSS), and one week of extended time (∼ 8 h 25 m) in bed corresponding to extended sleep (eSS), were counterbalanced in the SS group. The gating ERP assessment was performed on the last day after each sleep condition week (normal sleep and habitual short and extended sleep), and was separated by one week with habitual total sleep time and monitored by a sleep diary. We found that amplitude of gating was lower in SS group compared to that in NS group (0.3 µV vs. 1.2 µV, at Cz electrode respectively). The results of the group × laterality interaction showed that the reduction of gating amplitude in the SS group was due to lower amplitude over the left hemisphere and central-midline sites relative to that in the NS group. After sleep extension the amplitude of gating increased in chronic short sleeping individuals relative to their habitual short sleep condition. The sleep condition × frontality interaction analysis confirmed that sleep extension significantly increased the amplitude of gating over frontal and central brain areas compared to parietal brain areas.

Sleep extension normalizes ERP of waking auditory sensory gating in healthy habitually short sleeping individuals.

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Valentina Gumenyuk

Full Text Available Chronic sleep loss has been associated with increased daytime sleepiness, as well as impairments in memory and attentional processes. In the present study, we evaluated the neuronal changes of a pre-attentive process of wake auditory sensory gating, measured by brain event-related potential (ERP--P50 in eight normal sleepers (NS (habitual total sleep time (TST 7 h 32 m vs. eight chronic short sleeping individuals (SS (habitual TST ≤6 h. To evaluate the effect of sleep extension on sensory gating, the extended sleep condition was performed in chronic short sleeping individuals. Thus, one week of time in bed (6 h 11 m corresponding to habitual short sleep (hSS, and one week of extended time (∼ 8 h 25 m in bed corresponding to extended sleep (eSS, were counterbalanced in the SS group. The gating ERP assessment was performed on the last day after each sleep condition week (normal sleep and habitual short and extended sleep, and was separated by one week with habitual total sleep time and monitored by a sleep diary. We found that amplitude of gating was lower in SS group compared to that in NS group (0.3 µV vs. 1.2 µV, at Cz electrode respectively. The results of the group × laterality interaction showed that the reduction of gating amplitude in the SS group was due to lower amplitude over the left hemisphere and central-midline sites relative to that in the NS group. After sleep extension the amplitude of gating increased in chronic short sleeping individuals relative to their habitual short sleep condition. The sleep condition × frontality interaction analysis confirmed that sleep extension significantly increased the amplitude of gating over frontal and central brain areas compared to parietal brain areas.

Effect of smoking habits on sleep

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S.G. Conway

2008-08-01

Full Text Available To evaluate the effect of smoking habits on sleep, data from 1492 adults referred to the Sleep Institute were accessed and divided into 3 categories of smoking status: current, former and non-smokers. Categories of pack-years (<15 and ≥15 defined smoking severity. The association of smoking status and smoking severity with sleep was analyzed for sleep parameters, especially apnea and hypopnea index (AHI ≥5, more than 5% of total sleep time (TST spent with oxyhemoglobin saturation (SaO2 <90%, and arousal index. The arousal index was higher among current (21 ± 17 and former smokers (20 ± 17 than non-smokers (17 ± 15; P < 0.04. Former smokers had a higher percent of TST at SaO2 <90% than non-smokers (9 ± 18 vs 6 ± 13; P < 0.04. Former smokers with pack-years ≥15 compared to <15 exhibited higher AHI (22 ± 24 vs 16 ± 21; P < 0.05 and arousal index (22 ± 19 vs 18 ± 15; P < 0.05. Current smokers with pack-years ≥15 compared to <15 exhibited higher arousal index (23 ± 18 vs 18 ± 16; P < 0.05 and percent of TST at SaO2 <90% (11 ± 17 vs 6 ± 13; P < 0.05. Smoking status and pack-years were not associated with AHI ≥5 on logistic regression analysis, but current smokers with pack-years ≥15 were 1.9 times more likely to spend more than 5% of TST at SaO2 <90% than non-smokers (95%CI = 1.21-2.97; P = 0.005. The variability of arousal index was influenced by gender, AHI and current smokers with pack-years ≥15 (all P < 0.01. Smoking habits seem to be associated with arousal and oxyhemoglobin desaturation during sleep, but not with AHI. The effect was more pronounced in current than former smokers.

Subjectively and objectively measured sleep with and without posttraumatic stress disorder and trauma exposure.

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Kobayashi, Ihori; Huntley, Edward; Lavela, Joseph; Mellman, Thomas A

2012-07-01

Although reports of sleep disturbances are common among individuals with posttraumatic stress disorder (PTSD), results of polysomnographic (PSG) studies have inconsistently documented abnormalities and have therefore suggested "sleep state misperception." The authors' study objectives were to compare sleep parameters measured objectively and subjectively in the laboratory and at home in civilians with and without trauma exposure and PTSD. Cross-sectional study. PSG recordings in a sleep laboratory and actigraphic recordings in participants' homes. One hundred three urban-residing African Americans with and without trauma exposure and PTSD who participated in a larger study. N/A. Sleep parameters (total sleep time [TST], sleep onset latency [SOL], and wake after sleep onset [WASO]) were assessed using laboratory PSG and home actigraphy. A sleep diary was completed in the morning after PSG and actigraphy recordings. Habitual TST, SOL, and WASO were assessed using a sleep questionnaire. The Clinician Administered PTSD Scale was administered to assess participants' trauma exposure and PTSD diagnostic status. Participants, regardless of their trauma exposure/PTSD status, underestimated WASO in the diary and questionnaire relative to actigraphy and overestimated SOL in the diary relative to PSG. Among participants with current PTSD, TST diary estimates did not differ from the actigraphy measure in contrast with those without current PTSD who overestimated TST. No other significant group differences in discrepancies between subjective and objective sleep measures were found. Discrepancies between subjectively and objectively measured sleep parameters were not associated with trauma exposure or PTSD. This challenges prior assertions that individuals with PTSD overreport their sleep disturbances.

Short Sleep as an Environmental Exposure: A Preliminary Study Associating 5-HTTLPR Genotype to Self-Reported Sleep Duration and Depressed Mood in First-Year University Students

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Carskadon, Mary A.; Sharkey, Katherine M.; Knopik, Valerie S.; McGeary, John E.

2012-01-01

Objectives: This study examined whether the 5-HTTLPR polymorphism in the SLC6A4 gene is associated with self-reported symptoms of depressed mood in first-year university students with a persistent pattern of short sleep. Design: Students provided DNA samples and completed on-line sleep diaries and a mood scale during the first semester. A priori phenotypes for nocturnal sleep and mood scores were compared for the distribution of genotypes. Setting: Brown University, Providence, Rhode Island. Participants: A sample of 135 first-year students, 54 male, 71 Caucasian, mean age 18.1 (± 0.5) yr. Interventions: None. Measurements: Students completed on-line sleep diaries daily across the first term (21-64 days; mean = 51 days ± 11) and Center for Epidemiologic Studies-Depression (CES-D) mood scale after 8 wk. DNA was genotyped for the triallelic 5-HTTLPR polymorphism. Low-expressing S and LGpolymorphisms were designated S′, and high-expressing LA was designated L′. Phenotype groups were identified from a combination of CES-D (median split: high > 12; low sleep time (TST) from diaries: (shorter ≤ 7 hr; longer ≥ 7.5 hr). Three genotypes were identified (S′S′, S′L′, L′L′); the S′S′ genotype was present in a higher proportion of Asian than non-Asian students. Results: Four phenotype groups were compared: 40 students with shorter TST/high CES-D; 34 with shorter TST/low CES-D; 29 with longer TST/high CES-D; 32 with longer TST/low CES-D. Female:male distribution did not vary across phenotype groups (chi-square = 1.39; df = 3; P = 0.71). S′S′ participants (n = 23) were overrepresented in the shorter TST/high CES-D group (chi- square = 15.04; df = 6; P sleep and higher depressed mood are more likely than others to carry a variant of the SLC6A4 gene associated with low expression of the serotonin transporter. Citation: Carskadon MA; Sharkey KM; Knopik VS; McGeary JE. Short sleep as an environmental exposure: a preliminary study associating 5-HTTLPR

Habitual short sleep impacts frontal switch mechanism in attention to novelty.

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Gumenyuk, Valentina; Roth, Thomas; Korzyukov, Oleg; Jefferson, Catherine; Bowyer, Susan; Drake, Christopher L

2011-12-01

Reduced time in bed relative to biological sleep need is common. The impact of habitual short sleep on auditory attention has not been studied to date. In the current study, we utilized novelty oddball tasks to evaluate the effect of habitual short sleep on brain function underlying attention control processes measured by the mismatch negativity (MMN, index of pre-attentive stage), P3a (attention-dependent), and P3b (memory-dependent) event related brain potentials (ERPs). An extended time in bed in a separate study was used to evaluate the possible reversal of the impairments of these processes in habitual short sleepers. Ten self-defined short sleepers (total sleep time [TST] ≤ 6 h) and 9 normal-sleeping subjects with TST 7-8 h, participated. ERPs were recorded via a 64-channel EEG system. Two test conditions: "ignore" and "attend" were implemented. The ERPs were analyzed and compared between groups on the 2 task conditions and frontal/central/parietal electrodes by 3-factor ANOVA. Sleep diary data were compared between groups by t-test. Sleep was recorded by the Zeo sleep monitoring system for a week in both habitual and extended sleep conditions at home. The main findings of the present study show that short sleeping individuals had deficiency in activity of the MMN and P3a brain responses over frontal areas compared to normal-sleeping subjects. The P3b amplitude was increased over frontal areas and decreased over parietal with respect to the control group. Extension of time in bed for one week increased TST (from 5.7 h to 7.4 h), and concomitantly MMN amplitude increased from -0.1 μV up to -1.25 μV over frontal areas. Reduced time in bed is associated with deficiency of the neuronal process associated with change detection, which may recover after one week of sleep extension, whereas attention-dependent neural processes do not normalize after this period of time in habitually short sleeping individuals and may require longer recovery periods.

(Mis)perception of Sleep in Insomnia: A Puzzle and a Resolution

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Harvey, Allison G.; Tang, Nicole K. Y.

2012-01-01

Insomnia is prevalent, causing severe distress and impairment. This review focuses on illuminating the puzzling finding that many insomnia patients misperceive their sleep. They overestimate their sleep onset latency (SOL) and underestimate their total sleep time (TST), relative to objective measures. This tendency is ubiquitous (although not…

EEG Changes across Multiple Nights of Sleep Restriction and Recovery in Adolescents: The Need for Sleep Study.

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Ong, Ju Lynn; Lo, June C; Gooley, Joshua J; Chee, Michael W L

2016-06-01

To investigate sleep EEG changes in adolescents across 7 nights of sleep restriction to 5 h time in bed [TIB]) and 3 recovery nights of 9 h TIB. A parallel-group design, quasi-laboratory study was conducted in a boarding school. Fifty-five healthy adolescents (25 males, age = 15-19 y) who reported habitual TIBs of approximately 6 h on week nights (group average) but extended their sleep on weekends were randomly assigned to Sleep Restriction (SR) or Control groups. Participants underwent a 2-week protocol comprising 3 baseline nights (TIB = 9 h), 7 nights of sleep opportunity manipulation (TIB = 5 h for the SR and 9 h for the Control group), and 3 nights of recovery sleep (TIB = 9 h). Polysomnography was obtained on two baseline, three manipulation, and two recovery nights. Across the sleep restriction nights, total SWS duration was preserved relative to the 9 h baseline sleep opportunity, while other sleep stages were reduced. Considering only the first 5 h of sleep opportunity, SR participants had reduced N1 duration and wake after sleep onset (WASO), and increased total sleep time (TST), rapid eye movement (REM) sleep, and slow wave sleep (SWS) relative to baseline. Total REM sleep, N2, and TST duration remained above baseline levels by the third recovery sleep episode. In spite of preservation of SWS duration over multiple nights of sleep restriction, adolescents accustomed to curtailing nocturnal sleep on school day nights evidence residual effects on sleep macro-structure, even after three nights of recovery sleep. Older teenagers may not be as resilient to successive nights of sleep restriction as is commonly believed. © 2016 Associated Professional Sleep Societies, LLC.

Sleep, training load and performance in elite female gymnasts.

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Dumortier, J; Mariman, A; Boone, J; Delesie, L; Tobback, E; Vogelaers, D; Bourgois, J G

2018-03-01

Training load (TL) and recovery should be in optimal balance to obtain maximal performance gains. We aimed to study sleep as a recovery technique and its relationship with TL and performance in elite athletes. Twenty-six elite female artistic gymnasts were divided into an under 13 (n = 6), an under 14 (n = 6), a junior (n = 7; 14-15y) and a senior (=World Championship (WC) competitors, n = 7; ≥16y) category. Sleep, through sleep logs, and training parameters, using the session Rate of Perceived Exertion (sRPE) scale, were monitored to calculate total sleep time (TST), sleep efficiency (SE), TL, monotony and strain. Performance of WC competitors was evaluated through coach and WC qualification ranking. For the entire group, TST (effect sizes (ES) = -1.12, confidence intervals (CI) = -60:-47, P performance. Optimizing sleep and TL may therefore represent strategies to enhance performance.

Oxidative Stress and Inflammation Differentially Elevated in Objective Versus Habitual Subjective Reduced Sleep Duration in Obstructive Sleep Apnea.

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DeMartino, Theresanne; Ghoul, Rawad El; Wang, Lu; Bena, James; Hazen, Stanley L; Tracy, Russel; Patel, Sanjay R; Auckley, Dennis; Mehra, Reena

2016-07-01

Data have demonstrated adverse health effects of sleep deprivation. We postulate that oxidative stress and systemic inflammation biomarkers will be elevated in relation to short-term and long-term sleep duration reduction. We analyzed data from the baseline examination of a randomized controlled trial involving participants with moderate to severe obstructive sleep apnea (OSA). Baseline polysomnography provided the total sleep time (PSG-TST, primary predictor); self-reported habitual sleep duration (SR-HSD) data was collected. Morning measures of oxidative stress and systemic inflammation included: myeloperoxidase (MPO, pmol/L), oxidized low-density lipoprotein (ox-LDL, U/L), F2-isoprostane (ng/mg), paraoxonase 1 (PON1, nmol·min(-1)·mL(-1)), and aryl esterase (μmol·min(-1)·mL(-1)). Linear models adjusted for age, sex, race, body mass index (BMI), cardiovascular disease (CVD), smoking, statin/anti-inflammatory medications, and apnea-hypopnea index were utilized (beta estimates and 95% confidence intervals). One hundred forty-seven participants comprised the final analytic sample; they were overall middle-aged (51.0 ± 11.7 y), obese (BMI = 37.3 ± 8.1 kg/m(2)), and 17% had CVD. Multivariable models demonstrated a significant inverse association of PSG-TST and MPO (β [95% CI] = -20.28 [-37.48, -3.08], P = 0.021), i.e., 20.3 pmol/L MPO reduction per hour increase PSG-TST. Alternatively, a significant inverse association with ox-LDL and SR-HSD was observed (β [95% CI] = 0.98 [0.96, 0.99], P = 0.027), i.e., 2% ox-LDL reduction per hour increase SR-HSD. Even after consideration of obesity and OSA severity, inverse significant findings were observed such that reduced PSG-TST was associated with elevated MPO levels and SR-HSD with ox-LDL, suggesting differential up-regulation of oxidative stress and pathways of inflammation in acute versus chronic sleep curtailment. NIH clinical trials registry number NCT00607893. © 2016 Associated Professional Sleep Societies, LLC.

Shift work, night work and sleep disorders among pastry cookers and shopkeepers in France: a cross-sectional survey.

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Pepin, Emilie; Gillet, Pascal; Sauvet, Fabien; Gomez-Merino, Danielle; Thaon, Isabelle; Chennaoui, Mounir; Leger, Damien

2018-05-09

Most research on night and shift work focuses on employee health in large companies, primarily in the healthcare and transportation sectors. However, many night workers work on their own or in small businesses related to services or food. This survey focuses on sleep habits and disorders concerning night work in pastry production and sales. An epidemiological telephone cross-sectional survey of night shift workers and their sleep habits was proposed to all employers and employees in the French pastry industry via their insurance health prevention company. Sleep logs allow us to estimate the total sleep time (TST) on workdays and enquire on napping episodes and length. In order to estimate the ideal TST, we added a question on the ideal amount of sleep the subjects need to be in good shape in the morning. We also define sleep debt as the difference between the ideal TST and TST on workdays, and considered a sleep debt when the difference was above 60 min and severe sleep debt above 90 min. Finally we retained subjects as long sleepers for those with a TSTof more than 7 hours and short sleepers when TST was under 5 hours. Insomnia, sleepiness and sleep apnoea have been defined based on the International Classification of Sleep Disorders-Third Edition and the classification of mental disorders (Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition). Bivariate and multivariate logistic regression models were applied to investigate the association with short TST, long TST, sleep debt and napping. We analysed 2622 complete questionnaires from 1313 men and 1309 women aged 22-50 years old. 1397 workers began work before 07:00, whereas 1225 began later. The 24-hour TST was 6.7±1.4 hours, whereas the ideal TST was 7.0±1.2 hours. Severe sleep debt (>90 min) was reported by 6% women versus 5% men, whereas moderate sleep debt (>60 min) was reported by 11.5% women versus 9.3% men. Napping is one way to improve 24-hour TST for 58% of pastry

Sleep Quality but Not Quantity Altered With a Change in Training Environment in Elite Australian Rules Football Players.

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Pitchford, Nathan W; Robertson, Sam J; Sargent, Charli; Cordy, Justin; Bishop, David J; Bartlett, Jonathan D

2017-01-01

To assess the effects of a change in training environment on the sleep characteristics of elite Australian Rules football (AF) players. In an observational crossover trial, 19 elite AF players had time in bed (TIB), total sleep time (TST), sleep efficiency (SE), and wake after sleep onset (WASO) assessed using wristwatch activity devices and subjective sleep diaries across 8-d home and camp periods. Repeated-measures ANOVA determined mean differences in sleep, training load (session rating of perceived exertion [RPE]), and environment. Pearson product-moment correlations, controlling for repeated observations on individuals, were used to assess the relationship between changes in sleep characteristics at home and camp. Cohen effect sizes (d) were calculated using individual means. On camp TIB (+34 min) and WASO (+26 min) increased compared with home. However, TST was similar between home and camp, significantly reducing camp SE (-5.82%). Individually, there were strong negative correlations for TIB and WASO (r = -.75 and r = -.72, respectively) and a moderate negative correlation for SE (r = -.46) between home and relative changes on camp. Camp increased the relationship between individual s-RPE variation and TST variation compared with home (increased load r = -.367 vs .051, reduced load r = .319 vs -.033, camp vs home respectively). Camp compromised sleep quality due to significantly increased TIB without increased TST. Individually, AF players with higher home SE experienced greater reductions in SE on camp. Together, this emphasizes the importance of individualized interventions for elite team-sport athletes when traveling and/or changing environments.

Inter-device reliability of an automatic-scoring actigraph for measuring sleep in healthy adults

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Matthew Driller

2016-07-01

Full Text Available Actigraphy has become a common method of measuring sleep due to its non-invasive, cost-effective nature. An actigraph (Readiband™ that utilizes automatic scoring algorithms has been used in the research, but is yet to be evaluated for its inter-device reliability. A total of 77 nights of sleep data from 11 healthy adult participants was collected while participants were concomitantly wearing two Readiband™ actigraphs attached together (ACT1 and ACT2. Sleep indices including total sleep time (TST, sleep latency (SL, sleep efficiency (SE%, wake after sleep onset (WASO, total time in bed (TTB, wake episodes per night (WE, sleep onset variance (SOV and wake variance (WV were assessed between the two devices using mean differences, 95% levels of agreement, intraclass correlation coefficients (ICC, typical error of measurement (TEM and coefficient of variation (CV% analysis. There were no significant differences between devices for any of the measured sleep variables (p>0.05. TST, SE, SL, TTB, SOV and WV all resulted in very high ICC's (>0.90, with WASO and WE resulting in high ICC's between devices (0.85 and 0.80, respectively. Mean differences of −2.1 and 0.2 min for TST and SL were associated with a low TEM between devices (9.5 and 3.8 min, respectively. SE resulted in a 0.3% mean difference between devices. The Readiband™ is a reliable tool for researchers using multiple devices of this brand in sleep studies to assess basic measures of sleep quality and quantity in healthy adult populations.

Actigraphy combined with EEG compared to polysomnography in sleep apnea patients

International Nuclear Information System (INIS)

Fietze, Ingo; Penzel, Thomas; Partinen, Markku; Sauter, Jochen; Küchler, Gert; Suvoro, Alexander; Hein, Holger

2015-01-01

An actigraph extended with electroencephalography (EEG), electroocculography (EOG) and electromyography (EMG) was compared to polysomnography in two studies on patients suffering from sleep disordered breathing. Study A with 30 subjects used a single lead EEG, and study B with 20 subjects used EOG and EMG in addition. Sleep was scored according to Rechtschaffen and Kales rules. Total sleep time (TST), sleep period time (SPT), sleep efficiency (SE), sustained sleep efficiency (SSE), sleep-onset latency (SL), and sleep stages were compared. For study A an epoch-by-epoch comparison of sleep stages revealed an overall agreement of 74.2%. Correlations were high for SE (0.98, p < 0.001), SSE (0.98, p < 0.001), TST (0.99, p < 0.001), SPT (0.99, p < 0.001), and SL (0.98, p < 0.001). Regarding the sleep stages, correlations were high for rapid eye movement (REM) (0.83, p < 0.001), light-sleep (0.78, p < 0.001), and deep sleep (0.73, p < 0.001). For study B, results of an epoch-by-epoch comparison of sleep stages showed an overall agreement of 75.5%. Correlations were high for SE (0.98, p < 0.001), SSE (0.98, p < 0.001), TST (0.87, p < 0.001), SL (0.98, p < 0.001), SPT (0.94, p < 0.001), and for rapid eye movement (REM) (0.91, p < 0.001), light-sleep (0.74, p < 0.001), and deep sleep (0.89, p < 0.001). In summary the study revealed high agreement between polysomnography and single lead EEG in sleep apnea patients. Deviations for REM were slightly higher for the single lead EEG compared to single lead EEG plus EOG/EMG. Both simplified systems proved to be reliable for comfortable out-patient sleep recording. (paper)

Night sleep influences white matter microstructure in bipolar depression.

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Benedetti, Francesco; Melloni, Elisa M T; Dallaspezia, Sara; Bollettini, Irene; Locatelli, Clara; Poletti, Sara; Colombo, Cristina

2017-08-15

Alteration of circadian rhythms and sleep disruption are prominent trait-like features of bipolar disorder (BD). Diffusion tensor imaging (DTI) measures suggest a widespread alteration of white matter (WM) microstructure in patients with BD. Sleep promotes myelination and oligodendrocyte precursor cells proliferation. We hypothesized a possible association between DTI measures of WM microstructure and sleep quantity measures in BD. We studied 69 inpatients affected by a depressive episode in course of type I BD. We used whole brain tract-based spatial statistics on DTI measures of WM microstructure: axial, radial, and mean diffusivity (AD, RD, MD), and fractional anisotropy (FA). Self-assessed measures of time asleep (TA) and total sleep time (TST) were extracted from the Pittsburgh Sleep Quality Index (PSQI). Actigraphic recordings were performed on a subsample of 23 patients. We observed a positive correlation of DTI measures of FA with actigraphic measures of TA and TST, and with PSQI measure of TA. DTI measures of RD inversely associated with actigraphic measure of TA, and with PSQI measures of TA and TST. Several WM tracts were involved, including corpus callosum, cyngulate gyrus, uncinate fasciculus, left superior and inferior longitudinal and fronto-occipital fasciculi, thalamic radiation, corona radiata, retrolenticular part of internal capsule and corticospinal tract. The study is correlational in nature, and no conclusion about a causal connection can be drawn. Reduced FA with increased RD and MD indicate higher water diffusivity associated with less organized myelin and/or axonal structures. Our findings suggest an association between sleep disruption and these measures of brain microstructure in specific tracts contributing to the functional connectivity in BD. Copyright © 2017 Elsevier B.V. All rights reserved.

Sleep complaints and daytime sleepiness among pharmaceutical students in Tripoli.

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Taher, Yousef A; Samud, Awatef M; Ratimy, Aya H; Seabe, Areeje M

2012-01-01

The effect of sleep difficulties has achieved a great deal of attention recently, with university students considered as a homogenized population, particularly affected by sleep habits. The objective of this study was to investigate whether Libyan college students experience sleep disturbance during their academic programmes. A cross-sectional survey was conducted in the college of Pharmacy, Tripoli University, during February 2010. A total of 201 students, including 179 females (89.05%) and 22 males (10.95%), were recruited from different academic levels. Data were collected using a structured questionnaire and included a number of life-style variables. Epworth Sleepiness Scale (ESS) was used for the assessment of daytime sleepiness. This study showed that the total sleep time (TST) on a weeknight was 6.40 h and 67 students reported napping during daytime. The TST plus naps totalled 7.39 h. Out of eight possible dozing situations, we found that the mean score for ESS was 8.78. In addition, 79 students showed an ESS score of >10. Furthermore, our results showed that the majority of students (>92%) reported poor sleep satisfaction with quality and duration of sleep hours. Thinking about difficulty of study but not increasing education programs or tea/coffee consumption is associated with sleep difficulties reported. Moreover, 77.6% of students reported an irregular sleep-wake schedule. These findings indicate that students experienced excessive daytime sleepiness. The TST of pharmaceutical students in Libya, as in other developing countries, is less than those reported by Western students. Students experienced various environmental demands during their college years and, their quality of sleep was negatively affected.

The Role of Sleep in Predicting College Academic Performance: Is It A Unique Predictor?

OpenAIRE

Taylor, Daniel J.; Vatthauer, Karlyn E.; Bramoweth, Adam D.; Ruggero, Camilo; Roane, Brandy

2013-01-01

Few studies have looked at the predictability of academic performance (i.e., cumulative grade point average [GPA]) using sleep when common nonsleep predictors of academic performance are included. The present project studied psychological, demographic, educational, and sleep risk factors of decreased academic performance in college undergraduates. Subjects (N = 867) completed a questionnaire packet and sleep diary. It was hypothesized that low total sleep time (TST), increased sleep onset lat...

Sleep on Long Haul Layovers and Pilot Fatigue at the Start of the Next Duty Period.

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Cosgrave, Jan; Wu, Lora J; van den Berg, Margo; Signal, T Leigh; Gander, Philippa H

2018-01-01

Layovers are critical for pilot recovery between flights and minimum layover durations are required by regulation. However, research on the factors affecting layover sleep and safety performance indicators (SPIs) before subsequent flights is relatively sparse. The present project combined data from 6 studies, including 8 long-range and 5 ultra-long range out-and-back trips across a range of different layover destinations (299 pilots in 4-person crews, 410 layovers, 1-3 d layover duration). Sleep was monitored via actigraphy from 3 d pre-trip to at least 3 d post-trip. Pilots rated their sleepiness (Karolinska Sleepiness Scale, KSS) and fatigue (Samn-Perelli scale, SP) at duty start for the inbound flight. Mixed model ANOVAs identified independent associations between fatigue and sleepiness SPIs and operational factors (domicile time of duty start for the inbound flight in six 4-h bins, layover duration, and total sleep time (TST) in the 24 h prior to inbound duty start). TST was greatest on layovers ending between 1200-1559 domicile time (time in the city from which the outbound flight departed) and TST was a significant predictor of both KSS and SP ratings at duty start for the inbound flight. TST in the 24 h prior to the inbound flight was greatest when duty start time allowed for the inclusion of a full domicile night time period. In this dataset, circadian end-time of layovers is a key determinant of pilot fatigue status at the beginning of the inbound duty period.Cosgrove J, Wu LJ, van den Berg M, Signal TL, Gander PH. Sleep on long haul layovers and pilot fatigue at the start of the next duty period. Aerosp Med Hum Perform. 2018; 89(1):19-25.

Sleep complaints and daytime sleepiness among pharmaceutical students in Tripoli

Directory of Open Access Journals (Sweden)

Yousef A. Taher

2012-10-01

Full Text Available Background: The effect of sleep difficulties has achieved a great deal of attention recently, with university students considered as a homogenized population, particularly affected by sleep habits. Aim: The objective of this study was to investigate whether Libyan college students experience sleep disturbance during their academic programmes. Methods: A cross-sectional survey was conducted in the college of Pharmacy, Tripoli University, during February 2010. A total of 201 students, including 179 females (89.05% and 22 males (10.95%, were recruited from different academic levels. Data were collected using a structured questionnaire and included a number of life-style variables. Epworth Sleepiness Scale (ESS was used for the assessment of daytime sleepiness. Results: This study showed that the total sleep time (TST on a weeknight was 6.40 h and 67 students reported napping during daytime. The TST plus naps totalled 7.39 h. Out of eight possible dozing situations, we found that the mean score for ESS was 8.78. In addition, 79 students showed an ESS score of >10. Furthermore, our results showed that the majority of students (>92% reported poor sleep satisfaction with quality and duration of sleep hours. Thinking about difficulty of study but not increasing education programs or tea/coffee consumption is associated with sleep difficulties reported. Moreover, 77.6% of students reported an irregular sleep–wake schedule. Conclusion: These findings indicate that students experienced excessive daytime sleepiness. The TST of pharmaceutical students in Libya, as in other developing countries, is less than those reported by Western students. Students experienced various environmental demands during their college years and, their quality of sleep was negatively affected.

Effect of Daytime Exercise on Sleep Eeg and Subjective Sleep

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Sasazawa, Y.; Kawada, T.; Kiryu, Y.

1997-08-01

This study was designed to assess the effects of daytime physical exercise on the quality of objective and subjective sleep by examining all-night sleep EEGs. The subjects were five male students, aged 19 to 20 years, who were in the habit of performing regular daytime exercise. The sleep polygraphic parameters in this study were sleep stage time as a percentage of total sleep time (%S1, %S2, %S(3+4), %SREM, %MT), time in bed (TIB), sleep time (ST), total sleep time (TST), sleep onset latency (SOL), waking from sleep, sleep efficiency, number of awakenings, number of stage shifts, number of spindles, and percentages of α and δ waves, all of which were determined by an automatic computer analysis system. The OSA questionnaire was used to investigate subjective sleep. The five scales of the OSA used were sleepiness, sleep maintenance, worry, integrated sleep feeling, and sleep initiation. Each sleep parameter was compared in the exercise and the non-exercise groups. Two-way analysis of variance was applied using subject factor and exercise factor. The main effect of the subject was significant in all parameters and the main effect of exercise in %S(3+4), SOL and sleep efficiency, among the objective sleep parameters. The main effects of the subject, except sleepiness, were significant, as was the main effect of exercise on sleep initiation, among the subjective sleep parameters. These findings suggest that daytime exercise shortened sleep latency and prolonged slow-wave sleep, and that the subjects fell asleep more easily on exercise days. There were also significant individual differences in both the objective and subjective sleep parameters.

CERT TST December 2015 Visit Summary

Energy Technology Data Exchange (ETDEWEB)

Little, Robert Currier [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Bailey, Teresa S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Gamblin, G. Todd [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Olinger, Chad Tracy [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pautz, Shawn D. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Williams, Alan B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2016-01-25

The annual PSAAP II TST visit to Texas A&M’s CERT Center was held on December 1-3, 2015. The agenda for the visit is attached. Non-TAMU attendees were: TST Members – Teresa Bailey (LLNL), Todd Gamblin (LLNL), Bob Little (LANL) – Chair, Chad Olinger (LANL), Shawn Pautz (SNL), Alan Williams (SNL);Other Lab staff – Skip Kahler (LANL), Ana Kupresanin (LLNL), and Rob Lowrie (LANL); AST Members – Nelson Hoffman (LANL) and Bob Voigt (Leidos) The TST wishes to express our appreciation to all involved with CERT for the high-quality posters and presentations and for the attention to logistics that enabled a successful visit. We have broken our comments into four sections: (1) Kudos, (2) Recommendations, (3) Feedback on Priorities for April Review, and (4) Follow-Up Activities with Labs.

Does Suspected Sleep Disordered Breathing Impact on the Sleep and Performance of Firefighting Volunteers during a Simulated Fire Ground Campaign?

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Sarah M. Jay

2016-01-01

Full Text Available Adequate sleep is fundamental to workplace performance. For volunteer firefighters who work in safety critical roles, poor performance at work can be life threatening. Extended shifts and sleeping conditions negatively impact sleep during multi-day fire suppression campaigns. Having sleep disordered breathing (SDB could contribute further to sleep deficits. Our aim was to investigate whether those with suspected SDB slept and performed more poorly during a fire ground simulation involving sleep restriction. Participants, n = 20 participated in a 3-day-4-night fire ground simulation. Based on oximetry desaturation index data collected during their participation, participants were retrospectively allocated to either a SDB (n = 8 or a non-SDB group (n = 12. The simulation began with an 8 h Baseline sleep (BL followed by two nights of restricted (4 h sleep and an 8 h recovery sleep (R. All sleeps were recorded using a standard electroencephalography (EEG montage as well as oxygen saturation. During the day, participants completed neurobehavioral (response time, lapses and subjective fatigue tasks. Mixed effects ANOVA were used to compare differences in sleep and wake variables. Analyses revealed a main effect of group for Total sleep (TST, REM , wake after sleep onset (WASO and Arousals/h with the SDB group obtaining less TST and REM and greater WASO and Arousals/h. The group × night interaction was significant for N3 with the SDB group obtaining 42 min less during BL. There was a significant main effect of day for RRT, lapses and subjective fatigue and a significant day × group interaction for RRT. Overall, the SDB group slept less, experienced more disturbed sleep and had poorer response time performance, which was exacerbated by the second night of sleep restriction. This could present a safety concern, particularly during longer campaigns and is worthy of further investigation. In addition, we would recommend promotion of awareness of SDB, its

Age-related influences of prior sleep on brain activation during verbal encoding

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Michelle B Jonelis

2012-04-01

Full Text Available Disrupted sleep is more common in older adults (OA than younger adults (YA, often co-morbid with other conditions. How these sleep disturbances affect cognitive performance is an area of active study. We examined whether brain activation during verbal encoding correlates with sleep quantity and quality the night before testing in a group of healthy OA and YA. Twenty-seven OA (ages 59-82 and twenty-seven YA (ages 19-36 underwent one night of standard polysomnography. Twelve hours post-awakening, subjects performed a verbal encoding task while undergoing functional MRI. Analyses examined the group (OA vs. YA by prior sleep quantity (Total Sleep Time (TST or quality (Sleep Efficiency (SE interaction on cerebral activation, controlling for performance. Longer TST promoted higher levels of activation in the bilateral anterior parahippocampi in OA and lower activation levels in the left anterior parahippocampus in YA. Greater SE promoted higher activation levels in the left posterior parahippocampus and right inferior frontal gyrus in YA, but not in OA. The roles of these brain regions in verbal encoding suggest, in OA, longer sleep duration may facilitate functional compensation during cognitive challenges. By contrast, in YA, shorter sleep duration may necessitate functional compensation to maintain cognitive performance, similar to what is seen following acute sleep deprivation. Additionally, in YA, better sleep quality may improve semantic retrieval processes, thereby aiding encoding.

Prevalence of abnormal sleep duration and excessive daytime sleepiness in pregnancy and the role of socio-demographic factors: comparing pregnant women with women in the general population.

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Signal, T Leigh; Paine, Sarah-Jane; Sweeney, Bronwyn; Priston, Monique; Muller, Diane; Smith, Alexander; Lee, Kathryn A; Huthwaite, Mark; Reid, Papaarangi; Gander, Philippa

2014-12-01

To compare the prevalence of self-reported abnormal sleep duration and excessive daytime sleepiness in pregnancy among Māori (indigenous New Zealanders) and non-Māori women versus the general population, and to examine the influence of socio-demographic factors. Self-reported total sleep time (TST) in 24-hrs, Epworth Sleepiness Scale scores and socio-demographic information were obtained from nullipara and multipara women aged 20-46 yrs at 35-37 weeks pregnant (358 Māori and 717 non-Māori), and women in the general population (381 Māori and 577 non-Māori). After controlling for ethnicity, age, socio-economic status, and employment status, pregnant women average 30 min less TST than women in the general population. The distribution of TST was also greater in pregnant women, who were 3 times more likely to be short sleepers (≤6 h) and 1.9 times more likely to be long sleepers (>9 h). In addition, pregnant women were 1.8 times more likely to report excessive daytime sleepiness (EDS). Pregnant women >30 years of age experienced greater age-related declines in TST. Identifying as Māori, being unemployed, and working at night increased the likelihood of reporting abnormal sleep duration across all women population in this study. EDS also more likely occurred among Māori women and women who worked at night. Pregnancy increases the prevalence of abnormal sleep duration and EDS, which are also higher among Māori than non-Māori women and those who do night work. Health professionals responsible for the care of pregnant women need to be well-educated about the importance of sleep and discuss sleep issues with the women they care for. Copyright © 2014 Elsevier B.V. All rights reserved.

Neighborhood Stress and Autonomic Nervous System Activity during Sleep.

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Mellman, Thomas Alan; Bell, Kimberly Ann; Abu-Bader, Soleman Hassan; Kobayashi, Ihori

2018-04-04

Stressful neighborhood environments are known to adversely impact health and contribute to health disparities but underlying mechanisms are not well understood. Healthy sleep can provide a respite from sustained sympathetic nervous system (SNS) activity. Our objective was to evaluate relationships between neighborhood stress and nocturnal and daytime SNS and parasympathetic nervous system (PNS) activity. Eighty five urban-residing African Americans (56.5% female; mean age of 23.0) participated. Evaluation included surveys of neighborhood stress and sleep-related vigilance; and continuous ECG and actigraphic recording in participants' homes from which heart rate variability (HRV) analysis for low frequency/high frequency (LF/HF) ratio and normalized high frequency (nHF), as indicators of SNS and PNS activity, respectively, and total sleep time (TST), and wake after sleep onset were derived. All significant relationships with HRV measures were from the sleep period. Neighborhood disorder correlated negatively with nHF (r = -.24, p = .035). There were also significant correlations of HRV indices with sleep duration and sleep fears. Among females, LF/HF correlated with exposure to violence, r = .39, p = .008 and nHF with census tract rates for violent crime (r = -.35, p = .035). In a stepwise regression, TST accounted for the variance contributed by violent crime to nHF in the female participants. Further investigation of relationships between neighborhood environments and SNS/PNS balance during sleep and their consequences, and strategies for mitigating such effects would have implications for health disparities.

Impact of sleep disordered breathing on behaviour among elementary school-aged children: a cross-sectional analysis of a large community-based sample.

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Smith, Dale L; Gozal, David; Hunter, Scott J; Philby, Mona F; Kaylegian, Jaeson; Kheirandish-Gozal, Leila

2016-12-01

Sleep disordered breathing (SDB) in children has been associated with inattention, impulsivity and hyperactivity, but the associations between SDB severity and the type and severity of behavioural disruption are unclear.1022 children aged 5-7 years old prospectively underwent sleep studies and behavioural assessments through completion of standardised instruments. Participants were subdivided into four categorical groups based on the apnoea-hypopnoea index (AHI; measured per hour of total sleep time (hTST)), i.e. Group 1: nonsnoring and AHI hTST -1 ; Group 2: habitual snoring and AHI hTST -1 ; Group 3: habitual snoring and AHI 1-5 hTST -1 ; and Group 4: habitual snoring and AHI >5 hTST -1 , followed by comparisons of behavioural functioning across the groups.All 10 behavioural variables differed significantly between Group 1 and all other groups. Post hoc comparisons indicated that Group 2 was the most impaired for most behavioural measures. Furthermore, differences between Group 2 and more severe sleep pathology conditions were rarely significant.This large community-based paediatric cohort confirms earlier findings highlighting a significant impact of SDB on behavioural regulation, with the greatest impact being already apparent among habitually snoring children. Thus, a likely low asymptote exists regarding SDB behavioural impact, such that further increases in severity do not measurably increase parent-rated difficulties with behavioural regulation relative to controls. Our findings do support the need for considering early intervention, particularly among those children manifesting a behavioural impact of SDB. Copyright ©ERS 2016.

Impact of Exposure to Dim Light at Night on Sleep in Female and Comparison with Male Subjects.

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Cho, Chul-Hyun; Yoon, Ho-Kyoung; Kang, Seung-Gul; Kim, Leen; Lee, Eun-Il; Lee, Heon-Jeong

2018-03-19

Light pollution has become a social and health issue. We performed an experimental study to investigate impact of dim light at night (dLAN) on sleep in female subjects, with measurement of salivary melatonin. The 25 female subjects (Group A: 12; Group B: 13 subjects) underwent a nocturnal polysomnography (NPSG) session with no light (Night 1) followed by an NPSG session randomly assigned to two conditions (Group A: 5; Group B: 10 lux) during a whole night of sleep (Night 2). Salivary melatonin was measured before and after sleep on each night. For further investigation, the female and male subjects of our previous study were collected (48 subjects), and differences according to gender were compared. dLAN during sleep was significantly associated with decreased total sleep time (TST; F=4.818, p=0.039), sleep efficiency (SE; F=5.072, p=0.034), and Stage R latency (F=4.664, p=0.041) for female subjects, and decreased TST (F=14.971, pfemale as well as in merged subjects. REM sleep showed a pronounced increase under 10 lux than under 5 lux in merged subjects, suggesting the possibility of subtle influences of dLAN on REM sleep.

Patient-ventilator asynchrony, leaks and sleep in patients with amyotrophic lateral sclerosis.

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Vrijsen, Bart; Testelmans, Dries; Belge, Catharina; Vanpee, Goele; Van Damme, Philip; Buyse, Bertien

2016-01-01

Sleeping with non-invasive ventilation (NIV) in amyotrophic lateral sclerosis appears to be accompanied by a high patient-ventilator asynchrony (PVA) index. This prospective observational cohort study quantifies PVA and leaks, and searches for effects of these events on sleep after polysomnographic NIV titration. Full-video polysomnography, with incorporation of transcutaneous carbon dioxide and ventilator software, was used to analyse sleep epoch-by-epoch and respiratory events and PVA breath-by-breath in 35 patients (17 non-bulbar). After diagnostic polysomnography, NIV was titrated during three consecutive nights. Sleep, PVA and leaks were evaluated at discharge and after one month. Results showed that non-bulbar patients improved in sleep architecture and oxygen and carbon dioxide levels while bulbar patients only improved oxygen saturation. PVA remained present at discharge (non-bulbar 54 (21-101) and bulbar 31 (9-39)/h sleep) and one month (non-bulbar 31 (9-39) and bulbar 32 (17-55)/h sleep), with ineffective effort as most prominent asynchrony. Leaks also persisted after titration (non-bulbar 16.6 (3.1-44.6) and bulbar 5.1 (0.0-19.5)% of total sleep time (TST)) and one month (non-bulbar 7.7 (1.4-29.3) and bulbar 12.7 (0.0-35.2)% TST). PVA and leaks have none to minor effect on sleep architecture. In conclusion, although PVA and leaks remain present after meticulous NIV titration, these events seem not to interfere with sleep.

Objective Sleep Structure and Cardiovascular Risk Factors in the General Population: The HypnoLaus Study

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Haba-Rubio, José; Marques-Vidal, Pedro; Andries, Daniela; Tobback, Nadia; Preisig, Martin; Vollenweider, Peter; Waeber, Gérard; Luca, Gianina; Tafti, Mehdi; Heinzer, Raphaël

2015-01-01

Study Objectives: To evaluate the association between objective sleep measures and metabolic syndrome (MS), hypertension, diabetes, and obesity. Design: Cross-sectional study. Setting: General population sample. Participants: There were 2,162 patients (51.2% women, mean age 58.4 ± 11.1). Interventions: Patients were evaluated for hypertension, diabetes, overweight/obesity, and MS, and underwent a full polysomnography (PSG). Measurements and Results: PSG measured variables included: total sleep time (TST), percentage and time spent in slow wave sleep (SWS) and in rapid eye movement (REM) sleep, sleep efficiency and arousal index (ArI). In univariate analyses, MS was associated with decreased TST, SWS, REM sleep, and sleep efficiency, and increased ArI. After adjustment for age, sex, smoking, alcohol, physical activity, drugs that affect sleep and depression, the ArI remained significantly higher, but the difference disappeared in patients without significant sleep disordered breathing (SDB). Differences in sleep structure were also found according to the presence or absence of hypertension, diabetes, and overweight/obesity in univariate analysis. However, these differences were attenuated after multivariate adjustment and after excluding subjects with significant SDB. Conclusions: In this population-based sample we found significant associations between sleep structure and metabolic syndrome (MS), hypertension, diabetes, and obesity. However, these associations were cancelled after multivariate adjustment. We conclude that normal variations in sleep contribute little if any to MS and associated disorders. Citation: Haba-Rubio J, Marques-Vidal P, Andries D, Tobback N, Preisig M, Vollenweider P, Waeber G, Luca G, Tafti M, Heinzer R. Objective sleep structure and cardiovascular risk factors in the general population: the HypnoLaus study. SLEEP 2015;38(3):391–400. PMID:25325467

Actigraphic Sleep Duration and Fragmentation in Older Women: Associations With Performance Across Cognitive Domains.

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Spira, Adam P; Stone, Katie L; Redline, Susan; Ensrud, Kristine E; Ancoli-Israel, Sonia; Cauley, Jane A; Yaffe, Kristine

2017-08-01

To determine the association of actigraphic sleep duration and fragmentation with cognition in community-dwelling older women. We studied 782 women (mean age = 87.4) of varied cognitive status from the Study of Osteoporotic Fractures who completed wrist actigraphy and the Modified Mini-Mental State Examination (3MS), California Verbal Learning Test-II-Short Form, digit span, verbal fluency tests, and the Trailmaking Test, Part B (Trails B). Total sleep time (TST) and wake after sleep onset (WASO) tertiles were our primary predictors. There were few significant associations in adjusted analyses. Compared to women with intermediate TST (mean = 430.1 minutes), those with the longest (508.7 minutes) had significantly poorer performance on the 3MS and phonemic and semantic fluency. Compared to women with the least WASO (31.5 minutes), those in the middle tertile (61.5 minutes) had significantly poorer delayed recall and those in the middle tertile and highest tertile (126.2 minutes) had poorer total recall and semantic fluency. We observed significant adjusted associations of TST with impaired 3MS performance and of WASO with impaired delayed recall, semantic fluency, and digit span. After excluding participants with adjudicated dementia diagnoses or indeterminate cognitive status, some adjusted associations remained but decreased in magnitude, others became nonsignificant, and a new association emerged. In community-dwelling older women, longer objectively measured sleep duration and greater sleep fragmentation are associated with poorer performance and impairment in only a subset of cognitive domains. Some of these associations may be driven by women with dementia in whom disturbed sleep and cognitive performance share an underlying neuropathological basis. Published by Oxford University Press on behalf of Sleep Research Society (SRS) 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Lip muscle training improves obstructive sleep apnea and objective sleep: a case report

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Hiroshi Suzuki

Full Text Available The present study assessed the potential of lip muscle training for improving sleep. A patient with heavy snoring, daytime sleepiness and dry mouth underwent lip muscle training. Lip closure force LCFmax increased by 67.3% and LCFmin by 152% post-training. AHI decreased from 12.2 to 3.9 events/h by reducing hypopneic episodes. TST, sleep stage N3 and REM sleep increased, and WASO, sleep stage N1, and AI decreased. The patient switched from mouth to nose breathing during sleep and stopped snoring. Improved LCF, by moving the tongue into the anterior-superior oral cavity, may increase upper airway space and reduce the hypopnea index.

Sleep and delirium in unsedated patients in the intensive care unit

DEFF Research Database (Denmark)

Boesen, H C; Andersen, J H; Bendtsen, A O

2016-01-01

. Delirium assessment was done using the confusion assessment method for the intensive care unit (CAM-ICU). RESULTS: Of four patients who were delirium free, only one had identifiable sleep on PSG. Sleep was disrupted with loss of circadian rhythm, and diminished REM sleep. In the remaining three patients...... the PSGs were atypical, meaning that no sleep signs were found, and sleep could not be quantified from the PSGs. Clinical total sleep time (ClinTST) ranged from 2.0-13.1 h in patients without delirium. Six patients with delirium all had atypical PSGs, so sleep could not be quantified. Short periods of REM......BACKGROUND: Sleep deprivation and delirium are major problems in the ICU. We aimed to assess the sleep quality by polysomnography (PSG) in relation to delirium in mechanically ventilated non-sedated ICU patients. METHODS: Interpretation of 24-h PSG and clinical sleep assessment in 14 patients...

Long-Term Pain Treatment Did Not Improve Sleep in Nursing Home Patients with Comorbid Dementia and Depression: A 13-Week Randomized Placebo-Controlled Trial

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Kjersti M. Blytt

2018-02-01

Full Text Available Objective: Previous research indicates that pain treatment may improve sleep among nursing home patients. We aimed to investigate the long-term effect of pain treatment on 24-h sleep patterns in patients with comorbid depression and dementia.Design: A 13-week, multicenter, parallel-group, double-blind, placebo-controlled randomized clinical trial conducted between August 2014 and September 2016.Setting: Long-term patients from 47 nursing homes in Norway.Participants: We included 106 patients with comorbid dementia and depression according to the Mini Mental Status Examination (MMSE and the Cornell Scale for Depression in Dementia (CSDD.Intervention: Patients who were not using analgesics were randomized to receive either paracetamol (3 g/day or placebo tablets. Those who already received pain treatment were randomized to buprenorphine transdermal system (maximum 10 μg/h/7 days or placebo transdermal patches.Measurements: Sleep was assessed continuously for 7 days by actigraphy, at baseline and in week 13. Total sleep time (TST, sleep efficiency (SE, sleep onset latency (SOL, wake after sleep onset (WASO, early morning awakening (EMA, and number of wake bouts (NoW were evaluated. In addition, daytime total sleep time (DTS was estimated. Pain was assessed with Mobilization-Observation-Behavior-Intensity-Dementia-2 Pain Scale (MOBID-2.Results: The linear mixed model analyses for TST, SE, SOL, WASO, EMA, NoW and DTS showed no statistically significant differences between patients who received active pain treatment and those who received placebo. Post hoc subgroup analyses showed that there were no statistically significant differences between active treatment and placebo from baseline to week 13 in patients who were in pain (MOBID-2 ≥ 3 at baseline, or in patients who had poor sleep (defined as SE < 85% at baseline. Patients who received active buprenorphine showed an increase in TST and SE compared to those who received active paracetamol

The Role of Environmental Factors on Sleep Patterns and School Performance in Adolescents

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Dimitriou, Dagmara; Le Cornu Knight, Frances; Milton, Patrick

2015-01-01

Background: Modern life, with its many distractions, is seeing sleep quantity and quality decline during adolescence. This is a concern as research persuasively demonstrates the negative impact of reduced sleep on academic achievement, both in terms of learning and behavior. Aims: This study examined the relationship between sleep and school functioning in adolescence, with a focus on environmental factors that might mediate this relationship. Sample and Method: Forty-seven adolescents took part. Sleep was measured using the School Sleep Habits Survey (SSHS) and a sleep diary. School records of year grade point averages provided a measure of academic achievement. Raven's Standard Progressive Matrices gave a measure of general cognitive processing. Environmental sleep factors falling into three groups, namely, stimulant consumption, media use and exercise, were measured using a self-report questionnaire. Results: An average of 7.08 h of sleep was reported. Correlations revealed that Total sleep time (TST) and bedtimes on weekdays were strongly associated with academic achievement. Morning/eveningness and sleep/wake behavior problems had a strong relationship with performance on the Ravens. Stimulant consumption and media use before bed revealed strong relationships with TST and bedtimes on weekdays. Crucially, mediation analyses confirmed that both caffeine consumption and electronic media use before bedtime were negatively associated with academic performance, via the mediating pathway by affecting sleep. Exercise was not associated with any of the sleep variables, but was associated with better academic performance. Conclusion: The current findings highlight that, now more than ever, parents, schools and policy makers must be aware of the negative effects of caffeinated substances marketed to students, and electronic media use on their sleep habits. Our findings suggest that targeting caffeine consumption and electronic media use before bed may represent effective

The role of environmental factors on sleep patterns and school performance in adolescents

Directory of Open Access Journals (Sweden)

Dagmara eDimitriou

2015-12-01

Full Text Available Background. Modern life, with its many distractions, is seeing sleep quantity and quality decline during adolescence. This is a concern as research persuasively demonstrates the negative impact of reduced sleep on academic achievement, both in terms of learning and behaviour.Aims. This study examined the relationship between sleep and school functioning in adolescence, with a focus on environmental factors that might mediate this relationship.Sample and method. Forty-seven adolescents took part. Sleep was measured using the School Sleep Habits Survey and a sleep diary. School records of year grade point averages provided a measure of academic achievement. Raven’s Standard Progressive Matrices gave a measure of general cognitive processing. Environmental sleep factors falling into three groups, namely, stimulant consumption, media use and exercise, were measured using a self-report questionnaire. Results. An average of 7.08 hours of sleep was reported. Correlations revealed that Total sleep time (TST and bedtimes on weekdays were strongly associated with academic achievement. Morning/eveningness and sleep/wake behaviour problems had a strong relationship with performance on the Ravens. Stimulant consumption and media use before bed revealed strong relationships with TST and bedtimes on weekdays. Crucially, mediation analyses confirmed that both caffeine consumption and electronic media use before bedtime were negatively associated with academic performance, via the mediating pathway by affecting sleep. Exercise was not associated with any of the sleep variables, but was associated with better academic performance.Conclusion. The current findings highlight that, now more than ever, parents, schools and policy makers must be aware of the negative effects of caffeinated substances marketed to students, and electronic media use on their sleep habits. Our findings suggest that targeting caffeine consumption and electronic media use before bed may

The Role of Environmental Factors on Sleep Patterns and School Performance in Adolescents.

Science.gov (United States)

Dimitriou, Dagmara; Le Cornu Knight, Frances; Milton, Patrick

2015-01-01

Modern life, with its many distractions, is seeing sleep quantity and quality decline during adolescence. This is a concern as research persuasively demonstrates the negative impact of reduced sleep on academic achievement, both in terms of learning and behavior. This study examined the relationship between sleep and school functioning in adolescence, with a focus on environmental factors that might mediate this relationship. Forty-seven adolescents took part. Sleep was measured using the School Sleep Habits Survey (SSHS) and a sleep diary. School records of year grade point averages provided a measure of academic achievement. Raven's Standard Progressive Matrices gave a measure of general cognitive processing. Environmental sleep factors falling into three groups, namely, stimulant consumption, media use and exercise, were measured using a self-report questionnaire. An average of 7.08 h of sleep was reported. Correlations revealed that Total sleep time (TST) and bedtimes on weekdays were strongly associated with academic achievement. Morning/eveningness and sleep/wake behavior problems had a strong relationship with performance on the Ravens. Stimulant consumption and media use before bed revealed strong relationships with TST and bedtimes on weekdays. Crucially, mediation analyses confirmed that both caffeine consumption and electronic media use before bedtime were negatively associated with academic performance, via the mediating pathway by affecting sleep. Exercise was not associated with any of the sleep variables, but was associated with better academic performance. The current findings highlight that, now more than ever, parents, schools and policy makers must be aware of the negative effects of caffeinated substances marketed to students, and electronic media use on their sleep habits. Our findings suggest that targeting caffeine consumption and electronic media use before bed may represent effective routes in alleviating modern teenage sleep debt, and in

An Objective Short Sleep Insomnia Disorder Subtype Is Associated With Reduced Brain Metabolite Concentrations In Vivo: A Preliminary Magnetic Resonance Spectroscopy Assessment.

Science.gov (United States)

Miller, Christopher B; Rae, Caroline D; Green, Michael A; Yee, Brendon J; Gordon, Christopher J; D'Rozario, Angela L; Kyle, Simon D; Espie, Colin A; Grunstein, Ronald R; Bartlett, Delwyn J

2017-11-01

To evaluate brain metabolites in objective insomnia subtypes defined from polysomnography (PSG): insomnia with short sleep duration (I-SSD) and insomnia with normal sleep duration (I-NSD), relative to good sleeping controls (GSCs). PSG empirically grouped insomnia patients into I-SSD (n = 12: mean [SD] total sleep time [TST] = 294.7 minutes [30.5]) or I-NSD (n = 19: TST = 394.4 minutes [34.9]). 1H magnetic resonance spectroscopy (MRS) acquired in the left occipital cortex (LOCC), left prefrontal cortex, and anterior cingulate cortex was used to determine levels of creatine, aspartate, glutamate, and glutamine (referenced to water). Glutathione, glycerophosphocholine, lactate, myoinositol, and N-acetylaspartate measurements were also obtained. Sixteen GSCs were included for comparison. Multivariate analysis of variance was used to evaluate differences in creatine, aspartate, glutamate, and glutamine. Aspartate and glutamine concentrations were reduced in the LOCC in I-SSD compared with I-NSD (both p sleep onset (r = -.40, p sleep study: Australia New Zealand Clinical Trials Registry (ANZCTR): https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=12612000050853. 12612000050853. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Sleep quality in nurses: a randomized clinical trial of day and night shift workers.

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Niu, Shu-Fen; Chu, Hsin; Chung, Min-Huey; Lin, Chun-Chieh; Chang, Yu-Shiun; Chou, Kuei-Ru

2013-07-01

The study investigated the number of days off nurses working night shifts need to recover their sleep quality to the level of daytime workers during their days off. This study included 30 day-shift nurses and 32 night-shift nurses. It was conducted as a randomized clinical trial in the medical and surgical wards of a medical center in northern Taiwan in May and June 2010 using sleep diaries and sleep parameters collected by actigraphy on different workdays and days off. On workdays, the night-shift group had significantly less total sleep time (TST) on Day 5 and significantly lower sleep efficiency (SE) on Day 3 than the day-shift group. TSTs of the two groups on days off were higher than those on workdays. On the 4th consecutive day off, higher TST, a decrease in WASO, and an increase in SE suggests that the night-shift group had recovered their sleep quality to the level of the day-shift group on their days off. The SE of the night-shift group exceeded that of the day-shift group after the 4th consecutive day off, though the difference was not statistically significant in the present study. Based on these data, it is recommended that night-shift workers arrange a period of at least 4 days off after 5 consecutive night shifts and at least 5 days off if the staff who have previously worked night shifts are being assigned a set of different shifts.

What wrist should you wear your actigraphy device on? Analysis of dominant vs. non-dominant wrist actigraphy for measuring sleep in healthy adults

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Matthew William Driller

Full Text Available OBJECTIVE: Differences in sleep results due to the placement of actigraphy devices (non-dominant vs. dominant wrist are yet to be determined. METHODS: 65 nights of data from 13 adult participants was collected while participants wore two actigraphy devices, one on each wrist. Sleep indices including total sleep time (TST, total time in bed (TTB, sleep efficiency (SE%, sleep latency (SL, wake after sleep onset (WASO, sleep onset time (SOT and wake time (WT were assessed between the two devices. RESULTS: There were no significant differences between devices for any of the measured sleep variables (p>0.05. SE%, SL and WASO resulted in high correlations between devices (0.89, 0.89 and 0.76, respectively, with all other sleep variables resulting in very high correlations (>0.90 between devices. CONCLUSIONS: Based on our results, it does not seem critical which wrist the actigraphy device is worn on for measuring key sleep variables.

Subjective Positive and Negative Sleep Variables Differentially Affect Cellular Immune Activity in a Breast Cancer Survivor: A Time-series Analysis Approach

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Magdalena Singer

2018-01-01

Full Text Available This study on a breast cancer survivor suffering from cancer-related fatigue (CaRF and depression investigated the bidirectional relationship between cellular immune activity and subjective sleep. The 49-year-old patient (breast cancer diagnosis 5 years before the study, currently in remission collected her full urine output for 28 days in 12-h intervals (8:00 p.m. to 8:00 a.m. and 8:00 a.m. to 8:00 p.m.. These urine samples were used to determine urinary neopterin (cellular immune activation marker and creatinine concentrations via high-pressure liquid chromatography (HPLC. Each morning, the patient answered questions on five sleep variables: sleep quality (SQ, sleep recreational value (SRV, total sleep time (TST, total wake time (TWT, and awakenings during sleep period (ADS. For the purpose of this study, the time series of the nighttime urinary neopterin levels and the five sleep variables were determined. Using centered moving average (CMA smoothing and cross-correlational analysis, this study showed that increases in the positive sleep variables SQ and SRV were followed by urinary neopterin concentration decreases after 96–120 h (SQ, lag 4: r = −0.411; p = 0.044; SRV: lag 4: r = −0.472; p = 0.021 and 120–144 h (SRV, lag 5: r = −0.464; p = 0.026. Increases in the negative sleep variable TWT, by contrast, were followed by increases in urinary neopterin concentrations 72–96 h later (lag 3: r = 0.522; p = 0.009. No systematic effects in the other direction, i.e., from urinary neopterin levels to sleep, were observed in this study. Although preliminary, the findings of this study highlight the benefit of carefully investigating temporal delays and directions of effects when studying the dynamic relationship between sleep and immune variables in the natural context of everyday life.

Moving beyond average values: assessing the night-to-night instability of sleep and arousal in DSM-IV-TR insomnia subtypes.

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Sánchez-Ortuño, M Montserrat; Carney, Colleen E; Edinger, Jack D; Wyatt, James K; Harris, Andrea

2011-04-01

We explored differences between individuals with DSM-IV-TR diagnoses of primary insomnia (PI) and insomnia related to a mental disorder (IMD) by using serial measurements of self-reported sleep variables (sleep onset latency, SOL; wake after sleep onset, WASO; total sleep time, TST; sleep efficiency, SE), and visual analogue scale ratings of 2 forms of bedtime arousal (cognitive and emotional). Furthermore, we sought to examine the relationship between sleep and arousal within each diagnostic subgroup. Between-group and within-group comparisons. Duke and Rush University Medical Centers, USA. One hundred eighty-seven insomnia sufferers (126 women, average age 47.15 years) diagnosed by sleep specialists at 2 sleep centers as PI patients (n=126) and IMD patients (n=61). N/A. Multilevel models for sleep measures indicated that IMD displayed significantly more instability across nights in their TST (i.e., larger changes) than did PI patients. With respect to pre-sleep arousal, IMD patients exhibited higher mean levels of emotional arousal, as well as more instability on the nightly ratings of this measure. Within the PI group, correlational analyses revealed a moderate relationship between the 2 arousal variables and SOL (r values 0.29 and 0.26), whereas the corresponding correlations were negligible and statistically nonsignificant in the IMD group. We found a number of differences on nighttime variables between those diagnosed with primary insomnia and those diagnosed with insomnia related to a mental disorder. These differences imply different perpetuating mechanisms involved in their ongoing sleep difficulties. Additionally, they support the categorical distinctiveness and the concurrent validity of these insomnia subtypes.

Obstructive sleep apnea in obese community-dwelling children: the NANOS study.

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Alonso-Álvarez, María Luz; Cordero-Guevara, José Aurelio; Terán-Santos, Joaquin; Gonzalez-Martinez, Mónica; Jurado-Luque, María José; Corral-Peñafiel, Jaime; Duran-Cantolla, Joaquin; Kheirandish-Gozal, Leila; Gozal, David

2014-05-01

Obesity in children is assumed to serve as a major risk factor in pediatric obstructive sleep apnea syndrome (OSAS). However, the prevalence of OSAS in otherwise healthy obese children from the community is unknown. To determine the prevalence of OSAS in obese children identified and recruited from primary care centers. A cross-sectional, prospective, multicenter study. Spanish children ages 3-14 y with a body mass index (BMI) greater than or equal to the 95th percentile for age and sex were randomly selected, and underwent medical history, snoring, and Pediatric Sleep Questionnaire (PSQ) assessments, as well as physical examination, nasopharyngoscopy, and nocturnal polysomnography (NPSG) recordings. Two hundred forty-eight children (54.4% males) with mean age of 10.8 ± 2.6 y were studied with a BMI of 28.0 ± 4.7 kg/m(2) corresponding to 96.8 ± 0.6 percentile when adjusted for age and sex. The mean respiratory disturbance index (RDI), obstructive RDI (ORDI), and obstructive apnea-hypopnea index (OAHI) were 5.58 ± 9.90, 5.06 ± 9.57, and 3.39 ± 8.78/h total sleep time (TST), respectively. Using ≥ 3/h TST as the cutoff for the presence of OSAS, the prevalence of OSAS ranged from 21.5% to 39.5% depending on whether OAHI, ORDI, or RDI were used. The prevalence of obstructive sleep apnea syndrome (OSAS) in obese children from the general population is high. Obese children should be screened for the presence of OSAS. ClinicalTrials.gov identifier: NCT01322763.

Inflammatory markers and obstructive sleep apnea in obese children: the NANOS study.

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Gileles-Hillel, Alex; Alonso-Álvarez, María Luz; Kheirandish-Gozal, Leila; Peris, Eduard; Cordero-Guevara, José Aurelio; Terán-Santos, Joaquin; Martinez, Mónica Gonzalez; Jurado-Luque, María José; Corral-Peñafiel, Jaime; Duran-Cantolla, Joaquin; Gozal, David

2014-01-01

Obesity and obstructive sleep apnea syndrome (OSA) are common coexisting conditions associated with a chronic low-grade inflammatory state underlying some of the cognitive, metabolic, and cardiovascular morbidities. To examine the levels of inflammatory markers in obese community-dwelling children with OSA, as compared to no-OSA, and their association with clinical and polysomnographic (PSG) variables. Methods. In this cross-sectional, prospective multicenter study, healthy obese Spanish children (ages 4-15 years) were randomly selected and underwent nocturnal PSG followed by a morning fasting blood draw. Plasma samples were assayed for multiple inflammatory markers. 204 children were enrolled in the study; 75 had OSA, defined by an obstructive respiratory disturbance index (RDI) of 3 events/hour total sleep time (TST). BMI, gender, and age were similar in OSA and no-OSA children. Monocyte chemoattractant protein-1 (MCP-1) and plasminogen activator inhibitor-1 (PAI-1) levels were significantly higher in OSA children, with interleukin-6 concentrations being higher in moderate-severe OSA (i.e., AHI > 5/hrTST; P < 0.01), while MCP-1 levels were associated with more prolonged nocturnal hypercapnia (P < 0.001). IL-6, MCP-1, and PAI-1 are altered in the context of OSA among community-based obese children further reinforcing the proinflammatory effects of sleep disorders such as OSA. This trial is registered with ClinicalTrials.gov NCT01322763.

Clinical characteristics of sleep disorders in patients with Parkinson's disease.

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Mao, Zhi-Juan; Liu, Chan-Chan; Ji, Su-Qiong; Yang, Qing-Mei; Ye, Hong-Xiang; Han, Hai-Yan; Xue, Zheng

2017-02-01

In order to investigate the sleep quality and influencing factors in patients with Parkinson's disease (PD), 201 PD patients were enrolled and underwent extensive clinical evaluations. Subjective sleep evaluation was assessed using the Pittsburgh Sleep Quality Index (PSQI), and the Epworth Sleepiness Scale (ESS). It was found that poor sleep quality (77.11%) and excessive daytime sleepiness (32.34%) were commonly seen in PD patients and positively correlated with disease severity. Then 70 out of the 201 PD patients and 70 age- and sex-matched controls underwent a polysomnographic recording. The parameters were compared between PD group and control group and the influencing factors of sleep in PD patients were analyzed. The results showed that sleep efficiency (SE) was significantly decreased (Psleep latency (SL) and the arousal index (AI) were increased (Psleep time (TST) were positively correlated with the Hoehn and Yahr (H&Y) stage. There was significant difference in the extent of hypopnea and hypoxemia between the PD group and the control group (Psleep quality and a high prevalence of sleep disorder, which may be correlated with the disease severity. Respiratory function and oxygen supply are also affected to a certain degree in PD patients.

The effects of spectral tuning of evening ambient light on melatonin suppression, alertness and sleep.

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Rahman, Shadab A; St Hilaire, Melissa A; Lockley, Steven W

2017-08-01

We compared the effects of bedroom-intensity light from a standard fluorescent and a blue- (i.e., short-wavelength) depleted LED source on melatonin suppression, alertness, and sleep. Sixteen healthy participants (8 females) completed a 4-day inpatient study. Participants were exposed to blue-depleted circadian-sensitive (C-LED) light and a standard fluorescent light (FL, 4100K) of equal illuminance (50lx) for 8h prior to a fixed bedtime on two separate days in a within-subject, randomized, cross-over design. Each light exposure day was preceded by a dim light (LED conditions compared to FL 30min prior to bedtime. EEG-based correlates of alertness corroborated the reduced alertness under C-LED conditions as shown by significantly increased EEG spectral power in the delta-theta (0.5-8.0Hz) bands under C-LED as compared to FL exposure. There was no significant difference in total sleep time (TST), sleep efficiency (SE%), and slow-wave activity (SWA) between the two conditions. Unlike melatonin suppression and alertness, a significant order effect was observed on all three sleep variables, however. Individuals who received C-LED first and then FL had increased TST, SE% and SWA averaged across both nights compared to individuals who received FL first and then C-LED. These data show that the spectral characteristics of light can be fine-tuned to attenuate non-visual responses to light in humans. Copyright © 2017 Elsevier Inc. All rights reserved.

Inflammatory Markers and Obstructive Sleep Apnea in Obese Children: The NANOS Study

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Alex Gileles-Hillel

2014-01-01

Full Text Available Introduction. Obesity and obstructive sleep apnea syndrome (OSA are common coexisting conditions associated with a chronic low-grade inflammatory state underlying some of the cognitive, metabolic, and cardiovascular morbidities. Aim. To examine the levels of inflammatory markers in obese community-dwelling children with OSA, as compared to no-OSA, and their association with clinical and polysomnographic (PSG variables. Methods. In this cross-sectional, prospective multicenter study, healthy obese Spanish children (ages 4–15 years were randomly selected and underwent nocturnal PSG followed by a morning fasting blood draw. Plasma samples were assayed for multiple inflammatory markers. Results. 204 children were enrolled in the study; 75 had OSA, defined by an obstructive respiratory disturbance index (RDI of 3 events/hour total sleep time (TST. BMI, gender, and age were similar in OSA and no-OSA children. Monocyte chemoattractant protein-1 (MCP-1 and plasminogen activator inhibitor-1 (PAI-1 levels were significantly higher in OSA children, with interleukin-6 concentrations being higher in moderate-severe OSA (i.e., AHI > 5/hrTST; P<0.01, while MCP-1 levels were associated with more prolonged nocturnal hypercapnia (P<0.001. Conclusion. IL-6, MCP-1, and PAI-1 are altered in the context of OSA among community-based obese children further reinforcing the proinflammatory effects of sleep disorders such as OSA. This trial is registered with ClinicalTrials.gov NCT01322763.

5 CFR 551.432 - Sleep time.

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Sleep time. 551.432 Section 551.432... FAIR LABOR STANDARDS ACT Hours of Work Special Situations § 551.432 Sleep time. (a) Except as provided in paragraph (b) of this section, bona fide sleep time that fulfills the following conditions shall...

29 CFR 553.222 - Sleep time.

Science.gov (United States)

2010-07-01

... 29 Labor 3 2010-07-01 2010-07-01 false Sleep time. 553.222 Section 553.222 Labor Regulations... Enforcement Employees of Public Agencies Tour of Duty and Compensable Hours of Work Rules § 553.222 Sleep time... enforcement personnel in accordance with section 7(a)(1) of the Act, the public agency may exclude sleep time...

Sleep Deprivation and Time-Based Prospective Memory.

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Esposito, Maria José; Occhionero, Miranda; Cicogna, PierCarla

2015-11-01

To evaluate the effect of sleep deprivation on time-based prospective memory performance, that is, realizing delayed intentions at an appropriate time in the future (e.g., to take a medicine in 30 minutes). Between-subjects experimental design. The experimental group underwent 24 h of total sleep deprivation, and the control group had a regular sleep-wake cycle. Participants were tested at 08:00. Laboratory. Fifty healthy young adults (mean age 22 ± 2.1, 31 female). 24 h of total sleep deprivation. Participants were monitored by wrist actigraphy for 3 days before the experimental session. The following cognitive tasks were administered: one time-based prospective memory task and 3 reasoning tasks as ongoing activity. Objective and subjective vigilance was assessed by the psychomotor vigilance task and a visual analog scale, respectively. To measure the time-based prospective memory task we assessed compliance and clock checking behavior (time monitoring). Sleep deprivation negatively affected time-based prospective memory compliance (P sleep deprivation on human behavior, particularly the ability to perform an intended action after a few minutes. Sleep deprivation strongly compromises time-based prospective memory compliance but does not affect time check frequency. Sleep deprivation may impair the mechanism that allows the integration of information related to time monitoring with the prospective intention. © 2015 Associated Professional Sleep Societies, LLC.

(Mis)perception of sleep in insomnia: a puzzle and a resolution.

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Harvey, Allison G; Tang, Nicole K Y

2012-01-01

Insomnia is prevalent, causing severe distress and impairment. This review focuses on illuminating the puzzling finding that many insomnia patients misperceive their sleep. They overestimate their sleep onset latency (SOL) and underestimate their total sleep time (TST), relative to objective measures. This tendency is ubiquitous (although not universal). Resolving this puzzle has clinical, theoretical, and public health importance. There are implications for assessment, definition, and treatment. Moreover, solving the puzzle creates an opportunity for real-world applications of theories from clinical, perceptual, and social psychology as well as neuroscience. Herein we evaluate 13 possible resolutions to the puzzle. Specifically, we consider the possible contribution, to misperception, of (1) features inherent to the context of sleep (e.g., darkness); (2) the definition of sleep onset, which may lack sensitivity for insomnia patients; (3) insomnia being an exaggerated sleep complaint; (4) psychological distress causing magnification; (5) a deficit in time estimation ability; (6) sleep being misperceived as wake; (7) worry and selective attention toward sleep-related threats; (8) a memory bias influenced by current symptoms and emotions, a confirmation bias/belief bias, or a recall bias linked to the intensity/recency of symptoms; (9) heightened physiological arousal; (10) elevated cortical arousal; (11) the presence of brief awakenings; (12) a fault in neuronal circuitry; and (13) there being 2 insomnia subtypes (one with and one without misperception). The best supported resolutions were misperception of sleep as wake, worry, and brief awakenings. A deficit in time estimation ability was not supported. We conclude by proposing several integrative solutions.

Convergence in Sleep Time Accomplished? Gender Gap in Sleep Time for Middle-Aged Adults in Korea.

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Cha, Seung-Eun; Eun, Ki-Soo

2018-04-19

Although the gender gap in sleep time has narrowed significantly in the last decade, middle-aged women between ages 35 and 60 still sleep less than their male counterparts in Korea. This study examines and provides evidence for factors contributing to the gender gap in this age group. Using Korean Time Use Survey (KTUS) data from 2004, 2009 and 2014, we find that middle-aged women’s difficulty in managing work-life balance and traditional role expectations placed upon women are the main causes of the gender gap in sleep time. The decomposition analysis reveals that the improved socioeconomic status and recent changes in familial expectations for women may have helped them sleep more than in the past. However, there remain fundamental differences in attitude and time use patterns between men and women that prevent middle-aged women from getting the same amount of sleep.

Comparison of TST and IGRA in Diagnosis of Latent Tuberculosis Infection in a High TB-Burden Setting.

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Sharma, Surendra K; Vashishtha, Richa; Chauhan, L S; Sreenivas, V; Seth, Divya

2017-01-01

There are currently two tests for diagnosing latent tuberculosis infection (LTBI); TST and IGRA. However, it is still unclear that which one of these tests performs better in high TB-burden settings. 1511 household contacts of pulmonary TB patients were enrolled to compare the performance of TST and IGRA for LTBI. At baseline all participant underwent testing for IGRA [QuantiFERON-TB® Gold In-tube (QFT-GIT) assay] and TST [2 tuberculin unit (TU), purified protein derivative (PPD), RT23, Staten Serum Institute (SSI), Copenhagen, Denmark]. All the household contacts were followed-up for two years for incident TB cases. Active TB was diagnosed in 76 household contacts at an incidence rate of 2.14 per 1000 person-years. Both, TST [Hazard Ratio (HR): 1.14, 95% confidence interval (CI): 0.72-1.79, p = 0.57], as well as QFT-GIT assay (HR: 1.66, 95% CI: 0.97-2.84, p = 0.06) results at baseline were not significantly associated with subsequent development of active TB among household contacts of pulmonary TB patients. Neither TST nor IGRA predicted subsequent development of active TB among household contacts of pulmonary TB patients during follow-up. However, keeping in view the cost, and other logistics, TST remains the most preferred method for LTBI diagnosis in resource-limited, high TB-burden settings.

Clusters of Insomnia Disorder: An Exploratory Cluster Analysis of Objective Sleep Parameters Reveals Differences in Neurocognitive Functioning, Quantitative EEG, and Heart Rate Variability.

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Miller, Christopher B; Bartlett, Delwyn J; Mullins, Anna E; Dodds, Kirsty L; Gordon, Christopher J; Kyle, Simon D; Kim, Jong Won; D'Rozario, Angela L; Lee, Rico S C; Comas, Maria; Marshall, Nathaniel S; Yee, Brendon J; Espie, Colin A; Grunstein, Ronald R

2016-11-01

To empirically derive and evaluate potential clusters of Insomnia Disorder through cluster analysis from polysomnography (PSG). We hypothesized that clusters would differ on neurocognitive performance, sleep-onset measures of quantitative ( q )-EEG and heart rate variability (HRV). Research volunteers with Insomnia Disorder (DSM-5) completed a neurocognitive assessment and overnight PSG measures of total sleep time (TST), wake time after sleep onset (WASO), and sleep onset latency (SOL) were used to determine clusters. From 96 volunteers with Insomnia Disorder, cluster analysis derived at least two clusters from objective sleep parameters: Insomnia with normal objective sleep duration (I-NSD: n = 53) and Insomnia with short sleep duration (I-SSD: n = 43). At sleep onset, differences in HRV between I-NSD and I-SSD clusters suggest attenuated parasympathetic activity in I-SSD (P insomnia clusters derived from cluster analysis differ in sleep onset HRV. Preliminary data suggest evidence for three clusters in insomnia with differences for sustained attention and sleep-onset q -EEG. Insomnia 100 sleep study: Australia New Zealand Clinical Trials Registry (ANZCTR) identification number 12612000049875. URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=347742. © 2016 Associated Professional Sleep Societies, LLC.

Sleep duration and its association with demographics, lifestyle factors, poor mental health and chronic diseases in older Chinese adults.

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Wang, Shibin; Wu, Yanhua; Ungvari, Gabor S; Ng, Chee H; Forester, Brent P; Gatchel, Jennifer R; Chiu, Helen F K; Kou, Changgui; Fu, Yingli; Qi, Yue; Yu, Yaqin; Li, Bo; Xiang, Yu-Tao

2017-11-01

This study investigated the total sleep time (TST) and its associated factors in an older Chinese adult population. Multistage stratified cluster sampling was used in this cross-sectional study. A total of 4,115 older adults aged 60 to 79 years were selected and interviewed. Sleep duration was classified as short (8h per day) and medium sleep (7-8h per day). The total mean sleep time was 6.86±1.75h. Short and long sleepers accounted for 45.2% and 14.8% of the sample, respectively. Multivariate logistic regression analysis revealed that inadequate fruit intake and poor mental health were positively associated with short sleep, and married/cohabitation status and living in rural areas was negatively associated with short sleep. In addition, aged 75-79 years old, inadequate fruit intake, poor mental health and multi-morbidity were positively associated with long sleep. Ischemic heart disease, COPD and chronic gastroenteritis/peptic ulcer were positively associated with short sleep duration, while hyperlipidemia, hypertension, cerebrovascular diseases, and urolithiasis were positively associated with long sleep duration. Given the high frequency of aberrant sleep duration and its negative health impact, health professionals should pay more attention to sleep patterns in older people. Copyright © 2017 Elsevier B.V. All rights reserved.

Work Time Control and Sleep Disturbances

DEFF Research Database (Denmark)

Salo, Paula; Ala-Mursula, Leena; Rod, Naja Hulvej

2014-01-01

OBJECTIVES: Employee control over work times has been associated with favorable psychosocial and health-related outcomes, but the evidence regarding sleep quality remains inconclusive. We examined cross-sectional and prospective associations between work time control and sleep disturbances...... in a large working population, taking into account total hours worked. METHODS: The data were from a full-panel longitudinal cohort study of Finnish public sector employees who responded to questions on work time control and sleep disturbances in years 2000-2001, 2004-2005, 2008-2009, and 2012. The analysis....... RESULTS: Consistently in both cross-sectional and longitudinal models, less control over work time was associated with greater sleep disturbances in the total population and among those working normal 40-hour weeks. Among participants working more than 40 hours a week, work time that was both very high...

The study of subjective and objective evaluation of sleep disturbances in Parkinson's disease

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LIU Chun-feng

2013-08-01

Full Text Available Background Sleep disorder is one of the most common non-motor symptoms in Parkinson's disease (PD patients. At present, there are subjective and objective tools to evaluate sleepdisorders. Nevertheless, previous studies commonly used single subjective questionnaires or objective examinations. Therefore, we used the combinations of subjective and objective tools to analyze clinical characteristics of sleep disturbances in PD and investigated differences and consistence between subjective and objective tools. Methods One hundred and sixteen PD patients were eligible to participate into this study. All participants were evaluated by Pittsburgh Sleep Quality Index (PSQI, Unified Parkinson's Disease Rating Scale (UPDRS in "on" condition, Hoehn-Yahr (H-Y stage, Hamilton Depression Rating Scale (HAMD 24 items, Montreal Cognitive Assessment (MoCA, Epworth Sleepiness Scale (ESS, and underwent a video-polysomnography (Video-PSG. Results According to PSQI score of 116 PD patients, the proportion of PD patients with sleep disturbances (PSQI ≥ 7 was 50% (N = 58. Compared to PD patients without sleep disturbances, PD patients with sleep disturbances had lower score of MoCA (23.34 ± 3.50 vs 24.89 ± 3.52; t = 2.377, P = 0.019, higher score of UPDRSⅠ[4.00 (2.00, 5.00 vs 3.00 (2.00, 5.00; U = - 2.306, P = 0.021], UPDRSⅡ[12.00 (9.00, 16.00 vs 10.00 (6.00, 13.00; U = - 1.995, P = 0.046], higher levodopa equivalent daily dose [LED, (508.14 ± 335.85 vs (394.06 ± 236.40 mg/d; t = - 2.115, P = 0.037]. Although PD patients with sleep disturbances had more score of UPDSR Ⅲ and higher H-Y stage, the differences were not significant (P > 0.05. On the other hand, decreased total sleep time (TST, reduced sleep efficiency (SE, increased sleep latency (SL, decreased non-rapid eye movement (NREM sleep stage Ⅱ time were found for PD patients with sleep disturbances (P 0.05, for all. The score of PSQI was positively correlated with the score of ESS (r = 0.200, P = 0

Cross-cultural differences in the sleep of preschool children.

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Mindell, Jodi A; Sadeh, Avi; Kwon, Robert; Goh, Daniel Y T

2013-12-01

The aim of our study was to characterize cross-cultural sleep patterns and sleep problems in a large sample of preschool children ages 3-6years in multiple predominantly Asian (P-A) and predominantly Caucasian (P-C) countries/regions. Parents of 2590 preschool-aged children (P-A countries/regions: China, Hong Kong, India, Japan, Korea, Malaysia, Philippines, Singapore, Thailand; P-C countries: Australia-New Zealand, Canada, United Kingdom, United States) completed an Internet-based expanded version of the Brief Child Sleep Questionnaire (BCSQ). Overall, children from P-A countries had significantly later bedtimes, shorter nighttime sleep, and increased parental perception of sleep problems compared with those from P-C countries. Bedtimes varied from as early as 7:43pm in Australia and New Zealand to as late as 10:26pm in India, a span of almost 3h. There also were significant differences in daytime sleep with the majority of children in P-A countries continuing to nap, resulting in no differences in 24-h total sleep times (TST) across culture and minimal differences across specific countries. Bed sharing and room sharing are common in P-A countries, with no change across the preschool years. There also were a significant percentage of parents who perceived that their child had a sleep problem (15% in Korea to 44% in China). Overall, our results indicate significant cross-cultural differences in sleep patterns, sleeping arrangements, and parent-reported sleep problems in preschool-aged children. Further studies are needed to understand the underlying bases for these differences and especially for contributors to parents' perceptions of sleep problems. Copyright © 2013 Elsevier B.V. All rights reserved.

Cough Aerosol Cultures of Mycobacterium tuberculosis: Insights on TST / IGRA Discordance and Transmission Dynamics.

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Edward C Jones-López

Full Text Available The diagnosis of latent tuberculosis (TB infection (LTBI is complicated by the absence of a gold standard. Discordance between tuberculin skin tests (TST and interferon gamma release assays (IGRA occurs in 10-20% of individuals, but the underlying mechanisms are poorly understood.We analyzed data from a prospective household contact study that included cough aerosol culture results from index cases, environmental and contact factors. We assessed contacts for LTBI using TST and IGRA at baseline and six weeks. We examined TST/IGRA discordance in qualitative and quantitative analyses, and used multivariable logistic regression analysis with generalized estimating equations to analyze predictors of discordance.We included 96 TB patients and 384 contacts. Discordance decreased from 15% at baseline to 8% by six weeks. In adjusted analyses, discordance was related to less crowding (p = 0.004, non-cavitary disease (OR 1.41, 95% CI: 1.02-1.96; p = 0.03, and marginally with BCG vaccination in contacts (OR 1.40, 95% CI: 0.99-1.98, p = 0.06.We observed significant individual variability and temporal dynamism in TST and IGRA results in household contacts of pulmonary TB cases. Discordance was associated with a less intense infectious exposure, and marginally associated with a BCG-mediated delay in IGRA conversion. Cough aerosols provide an additional dimension to the assessment of infectiousness and risk of infection in contacts.

American time use survey: sleep time and its relationship to waking activities.

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Basner, Mathias; Fomberstein, Kenneth M; Razavi, Farid M; Banks, Siobhan; William, Jeffrey H; Rosa, Roger R; Dinges, David F

2007-09-01

To gain some insight into how various behavioral (lifestyle) factors influence sleep duration, by investigation of the relationship of sleep time to waking activities using the American Time Use Survey (ATUS). Cross-sectional data from ATUS, an annual telephone survey of a population sample of US citizens who are interviewed regarding how they spent their time during a 24-hour period between 04:00 on the previous day and 04:00 on the interview day. Data were pooled from the 2003, 2004, and 2005 ATUS databases involving N=47,731 respondents older than 14 years of age. N/A. Adjusted multiple linear regression models showed that the largest reciprocal relationship to sleep was found for work time, followed by travel time, which included commute time. Only shorter than average sleepers (socializing, relaxing, and engaging in leisure activities, while both short ( or =8.5 h) watched more TV than the average sleeper. The extent to which sleep time was exchanged for waking activities was also shown to depend on age and gender. Sleep time was minimal while work time was maximal in the age group 45-54 yr, and sleep time increased both with lower and higher age. Work time, travel time, and time for socializing, relaxing, and leisure are the primary activities reciprocally related to sleep time among Americans. These activities may be confounding the frequently observed association between short and long sleep on one hand and morbidity and mortality on the other hand and should be controlled for in future studies.

Electronic Media Use and Sleep Among Preschoolers: Evidence for Time-Shifted and Less Consolidated Sleep.

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Beyens, Ine; Nathanson, Amy I

2018-01-11

This study examined the association between electronic media use and sleep among preschoolers, using a national sample of 402 mothers of 3- to 5-year-olds. Participants completed an online survey assessing preschoolers' electronic media use, bedtime and wake time, sleep time, napping behaviors, and sleep consolidation. Results showed that heavier television use and tablet use, both overall and in the evening, were associated with later bedtimes and later wake times, but not with fewer hours of sleep, providing evidence for a time-shifting process. In addition, heavier daily television use and evening smartphone use were associated with increased daytime napping. Moreover, heavier daily television use, daily and evening smartphone use, and evening tablet use were associated with poorer sleep consolidation, suggesting less mature sleep patterns. These findings indicate that media effects on the timing of sleep and the proportion of sleep that occurs at night are important to consider when assessing the health risks of electronic media on children.

Systematic review of TST responses in people living with HIV in under-resourced settings: implications for isoniazid preventive therapy.

Directory of Open Access Journals (Sweden)

Andrew D Kerkhoff

Full Text Available People living with HIV (PLWH who have positive tuberculin skin tests (TST benefit from isoniazid preventive therapy (IPT whereas those testing TST-negative do not. Revised World Health Organization guidelines explicitly state that assessment of TST is not a requirement for initiation of IPT. However, it is not known what proportions of patients will benefit from IPT if implemented without targeting according to TST status. We therefore determined the proportions of PLWH who test TST-positive.We systematically reviewed the literature published between January 1990 and February 2012 to determine the proportions of patients without active tuberculosis attending HIV care services in low and middle-income countries who tested TST-positive (≥5 mm induration. Proportions were also determined for different CD4 count strata. Data from 19 studies with 9,478 PLWH from sub-Saharan Africa, Asia and Central and South America were summarized. The vast majority were not receiving antiretroviral therapy (ART. A sub-analysis was conducted of 5 studies (5,567 subjects from high TB prevalence countries of PLWH with negative TB screens attending HIV care and treatment settings for whom CD4 stratified data were available. The median proportion of PLWH testing TST-positive overall was 22.8% (range, 19.5-32.6%. The median (range proportions with CD4 cell counts of <200, 200-499 or ≥500 cells/µL who tested positive were 12.4% (8.2-15.3%, 28.4% (20.1-36.9% and 37.4% (31.3-56.3%, respectively. Heterogeneity in the data precluded calculation of pooled summary estimates.In most settings, if IPT is administered to PLWH pre-ART without assessment of TST status, only a minority of those treated are likely to benefit, especially among those with the lowest CD4 cell counts. This may be inefficient use of resources and cost-effectiveness analyses should take this into account. Local knowledge of TST response rates may help inform policies. New simple means of identifying

Correlates of adolescent sleep time and variability in sleep time: the role of individual and health related characteristics.

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Moore, Melisa; Kirchner, H Lester; Drotar, Dennis; Johnson, Nathan; Rosen, Carol; Redline, Susan

2011-03-01

Adolescents are predisposed to short sleep duration and irregular sleep patterns due to certain host characteristics (e.g., age, pubertal status, gender, ethnicity, socioeconomic class, and neighborhood distress) and health-related variables (e.g., ADHD, asthma, birth weight, and BMI). The aim of the current study was to investigate the relationship between such variables and actigraphic measures of sleep duration and variability. Cross-sectional study of 247 adolescents (48.5% female, 54.3% ethnic minority, mean age of 13.7years) involved in a larger community-based cohort study. Significant univariate predictors of sleep duration included gender, minority ethnicity, neighborhood distress, parent income, and BMI. In multivariate models, gender, minority status, and BMI were significantly associated with sleep duration (all pminority adolescents, and those of a lower BMI obtaining more sleep. Univariate models demonstrated that age, minority ethnicity, neighborhood distress, parent education, parent income, pubertal status, and BMI were significantly related to variability in total sleep time. In the multivariate model, age, minority status, and BMI were significantly related to variability in total sleep time (all pminority adolescents, and those of a lower BMI obtaining more regular sleep. These data show differences in sleep patterns in population sub-groups of adolescents which may be important in understanding pediatric health risk profiles. Sub-groups that may particularly benefit from interventions aimed at improving sleep patterns include boys, overweight, and minority adolescents. Copyright © 2011 Elsevier B.V. All rights reserved.

Start Later, Sleep Later: School Start Times and Adolescent Sleep in Homeschool vs. Public/Private School Students

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Meltzer, Lisa J.; Shaheed, Keisha; Ambler, Devon

2014-01-01

Homeschool students provide a naturalistic comparison group for later/flexible school start times. This study compared sleep patterns and sleep hygiene for homeschool students and public/private school students (grades 6-12). Public/private school students (n=245) and homeschool students (n=162) completed a survey about sleep patterns and sleep hygiene. Significant school group differences were found for weekday bedtime, wake time, and total sleep time, with homeschool students waking later and obtaining more sleep. Homeschool students had later school start times, waking at the same time that public/private school students were starting school. Public/private school students had poorer sleep hygiene practices, reporting more homework and use of technology in the hour before bed. Regardless of school type, technology in the bedroom was associated with shorter sleep duration. Later school start times may be a potential countermeasure for insufficient sleep in adolescents. Future studies should further examine the relationship between school start times and daytime outcomes, including academic performance, mood, and health. PMID:25315902

The multiple time scales of sleep dynamics as a challenge for modelling the sleeping brain.

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Olbrich, Eckehard; Claussen, Jens Christian; Achermann, Peter

2011-10-13

A particular property of the sleeping brain is that it exhibits dynamics on very different time scales ranging from the typical sleep oscillations such as sleep spindles and slow waves that can be observed in electroencephalogram (EEG) segments of several seconds duration over the transitions between the different sleep stages on a time scale of minutes to the dynamical processes involved in sleep regulation with typical time constants in the range of hours. There is an increasing body of work on mathematical and computational models addressing these different dynamics, however, usually considering only processes on a single time scale. In this paper, we review and present a new analysis of the dynamics of human sleep EEG at the different time scales and relate the findings to recent modelling efforts pointing out both the achievements and remaining challenges.

Effects of armodafinil and cognitive behavior therapy for insomnia on sleep continuity and daytime sleepiness in cancer survivors.

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Garland, Sheila N; Roscoe, Joseph A; Heckler, Charles E; Barilla, Holly; Gehrman, Philip; Findley, James C; Peoples, Anita R; Morrow, Gary R; Kamen, Charles; Perlis, Michael L

2016-04-01

This study involves the analysis of a secondary outcome of a trial examining whether cognitive behavior therapy for insomnia (CBT-I), a wake-promoting medication (armodafinil), or both results in greater improvement in prospectively assessed sleep continuity and daytime sleepiness than a placebo-alone group among a heterogeneous group of cancer survivors. Whether or not armodafinil alone, and/or when combined with CBT-I, affected adherence with CBT-I was evaluated. This study is a randomized, placebo-controlled, clinical trial. This study was conducted at two northeastern academic medical centers. Eighty-eight cancer survivors with chronic insomnia were recruited between October 2008 and November 2012. Participants were assigned to one of four conditions: 1) CBT-I and placebo (CBT-I+P); 2) CBT-I and armodafinil (CBT-I + A); 2) armodafinil alone (ARM); or 4) placebo alone (PLA). CBT-I was delivered in seven weekly individual therapy sessions (three in person, four via telephone). The armodafinil dosage was 50 mg BID. Sleep continuity was measured with daily sleep diaries assessing sleep latency (SL), wake after sleep onset (WASO), and total sleep time (TST). The Epworth Sleepiness Scale (ESS) measured daytime sleepiness. Compared to the PLA group, the CBT-I+P and CBT-I+A groups reported a significant reduction in SL with effect sizes of 0.67 and 0.58, respectively. A significant reduction was observed in WASO in the CBT-I+A group with an effect size of 0.64. An increasing trend of TST was observed in the CBT-I+P, CBT-I+A, and PLA groups, but not in the ARM group. No statistically significant reductions in daytime sleepiness (ESS) were observed for any of the groups. CBT-I alone and in combination with armodafinil caused significant improvement in sleep continuity. The addition of armodafinil did not appear to improve daytime sleepiness or enhance adherence to CBT-I. Copyright © 2015 Elsevier B.V. All rights reserved.

Seasonal variation in physical activity, sedentary behaviour and sleep in a sample of UK adults.

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O'Connell, Sophie E; Griffiths, Paula L; Clemes, Stacy A

2014-01-01

Physical activity (PA), sedentary behaviour (SB), sleep and diet have all been associated with increased risk for chronic disease. Seasonality is often overlooked as a determinant of these behaviours in adults. Currently, no study has simultaneously monitored these behaviours in UK adults to assess seasonal variation. The present study investigated whether PA, SB, sleep and diet differed over season in UK adults. Forty-six adults (72% female; age = 41.7 ± 14.4 years, BMI = 24.9 ± 4.4 kg/m(2)) completed four 7-day monitoring periods; one during each season of the year. The ActiGraph GT1M was used to monitor PA and SB. Daily sleep diaries monitored time spent in bed (TIB) and total sleep time (TST). The European Prospective Investigation of Cancer (EPIC) food frequency questionnaire (FFQ) assessed diet. Repeated measures ANOVAs were used to identify seasonal differences in behaviours. Light-intensity PA was significantly higher in summer and spring (p diet (p > 0.05). Findings support the concept that health promotion campaigns need to encourage year-round participation in light intensity PA, whilst limiting SB, particularly during the winter months.

The Timing of Sleep in Depression : Theoretical Considerations

NARCIS (Netherlands)

Beersma, Domien G.M.; Daan, Serge; Hoofdakker, Rutger H. van den

1985-01-01

Endogenously depressed subjects frequently show severe sleep problems. In this article sleep time in depression is discussed in relation to a recently developed model for sleep timing in healthy subjects. In terms of the model, two parameter sets survive a qualitative comparison with the empirical

Characteristics of sleep dysfunction and sleep - disordered breathing in amyotrophic lateral sclerosis patients

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Fang WANG

2017-10-01

Full Text Available Objective To study the characteristics of sleep architecture and sleep - disordered breathing (SDB in patients with amyotrophic lateral sclerosis (ALS using polysomnography (PSG. Methods A total of 36 patients with ALS were recruited in this study. According to symptoms of medulla oblongata, the patients were divided into limb involvement group (N = 14 and bulbar palsy group (N = 22. Detailed record of the patients was made including general information and chief complaints of sleep dysfunction and SDB, which covered sleep initiation and maintenance disorders, arousals, difficulty in breathing and snoring, nocturnal polyuria, restless legs syndrome (RLS and muscle soreness. Appel Amyotrophic Lateral Sclerosis (AALS Scores were used to assess bulbar function, breathing function,myodynamia and limbs function. PSG was performed to monitor EEG, EOG, EMG, ECG, position, snore, gas flow of mouth and nose, chest breathing, pulse oxygen saturation (SpO2 and sleep-related parameters including total sleep time (TST, sleep efficiency (SE, sleep latency (SL, awakening times, percentage of different non-rapid eye movement (NREM and rapial eye movement (REM, and apnea hypopnea index (AHI. Pearson correlation analysis evaluated the relationship between AHI of REM, periodic limb movements (PLM and clinical information, AALS Scores. Results Bulbar palsy group had higher scores in AALS Scores (P = 0.007, bulbar function (P = 0.000 and breathing function (P = 0.000, and lower score in upper limb myodynamia (P = 0.016 than limb involvement group. Both 2 groups showed disturbed sleep architecture in the performance of sleep fragmentation. Bulbar palsy group had more awakening times (P = 0.027, lower percentage of REM sleep (P = 0.009 and less PLM (P = 0.020 than limb involvement group. The main respiratory event of 2 groups was hypopnea. Bulbar palsy group had higher AHI (P = 0.038 and AHI of REM and NREM (P = 0.031, 0.049 than limb involvement group. Pearson

Habitual sleep durations and subjective sleep quality predict white matter differences in the human brain

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Sakh Khalsa

2017-06-01

inferior longitudinal fasciculus. Improved sleep quality was positively correlated with FA in left caudate nucleus, white matter tracts to the left orbito-frontal region, the left anterior cingulum bundle and the white matter tracts associated with the right operculum and insula, and negatively correlated with MD in left orbito-frontal white matter and the left anterior cingulum bundle. Our findings suggest that reduced cumulative total sleep time (cTST and poorer subjective sleep quality are associated with subtle white matter micro-architectural changes. The regions we identified as being related to habitual sleep patterns were restricted to the frontal and temporal lobes, and the functions they support are consistent with those which have previously been demonstrated as being affected by short sleep durations (e.g., attention, cognitive control, memory. Examining how inter-individual differences in brain structure are related to habitual sleep patterns could help to shed light on the mechanisms by which sleep habits are associated with brain function, behaviour and cognition, as well as potentially the networks and systems responsible for variations in sleep patterns themselves.

The relationship between sleep and wake habits and academic performance in medical students: a cross-sectional study.

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Bahammam, Ahmed S; Alaseem, Abdulrahman M; Alzakri, Abdulmajeed A; Almeneessier, Aljohara S; Sharif, Munir M

2012-08-01

The relationship between the sleep/wake habits and the academic performance of medical students is insufficiently addressed in the literature. This study aimed to assess the relationship between sleep habits and sleep duration with academic performance in medical students. This study was conducted between December 2009 and January 2010 at the College of Medicine, King Saud University, and included a systematic random sample of healthy medical students in the first (L1), second (L2) and third (L3) academic levels. A self-administered questionnaire was distributed to assess demographics, sleep/wake schedule, sleep habits, and sleep duration. Daytime sleepiness was evaluated using the Epworth Sleepiness Scale (ESS). School performance was stratified as "excellent" (GPA ≥ 3.75/5) or "average" (GPA students (males: 67%). One hundred fifteen students (28%) had "excellent" performance, and 295 students (72%) had "average" performance. The "average" group had a higher ESS score and a higher percentage of students who felt sleepy during class. In contrast, the "excellent" group had an earlier bedtime and increased TST during weekdays. Subjective feeling of obtaining sufficient sleep and non-smoking were the only independent predictors of "excellent" performance. Decreased nocturnal sleep time, late bedtimes during weekdays and weekends and increased daytime sleepiness are negatively associated with academic performance in medical students.

The Acute Effects of Intermittent Light Exposure in the Evening on Alertness and Subsequent Sleep Architecture.

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Yang, Minqi; Ma, Ning; Zhu, Yingying; Su, Ying-Chu; Chen, Qingwei; Hsiao, Fan-Chi; Ji, Yanran; Yang, Chien-Ming; Zhou, Guofu

2018-03-15

Exposure to bright light is typically intermittent in our daily life. However, the acute effects of intermittent light on alertness and sleep have seldom been explored. To investigate this issue, we employed within-subject design and compared the effects of three light conditions: intermittent bright light (30-min pulse of blue-enriched bright light (~1000 lux, ~6000 K) alternating with 30-min dim normal light (~5 lux, ~3600 K) three times); continuous bright light; and continuous dim light on subjective and objective alertness and subsequent sleep structure. Each light exposure was conducted during the three hours before bedtime. Fifteen healthy volunteers (20 ± 3.4 years; seven males) were scheduled to stay in the sleep laboratory for four separated nights (one for adaptation and the others for the light exposures) with a period of at least one week between nights. The results showed that when compared with dim light, both intermittent light and continuous bright light significantly increased subjective alertness and decreased sleep efficiency (SE) and total sleep time (TST). Intermittent light significantly increased objective alertness than dim light did during the second half of the light-exposure period. Our results suggested that intermittent light was as effective as continuous bright light in their acute effects in enhancing subjective and objective alertness and in negatively impacting subsequent sleep.

The Acute Effects of Intermittent Light Exposure in the Evening on Alertness and Subsequent Sleep Architecture

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Minqi Yang

2018-03-01

Full Text Available Exposure to bright light is typically intermittent in our daily life. However, the acute effects of intermittent light on alertness and sleep have seldom been explored. To investigate this issue, we employed within-subject design and compared the effects of three light conditions: intermittent bright light (30-min pulse of blue-enriched bright light (~1000 lux, ~6000 K alternating with 30-min dim normal light (~5 lux, ~3600 K three times; continuous bright light; and continuous dim light on subjective and objective alertness and subsequent sleep structure. Each light exposure was conducted during the three hours before bedtime. Fifteen healthy volunteers (20 ± 3.4 years; seven males were scheduled to stay in the sleep laboratory for four separated nights (one for adaptation and the others for the light exposures with a period of at least one week between nights. The results showed that when compared with dim light, both intermittent light and continuous bright light significantly increased subjective alertness and decreased sleep efficiency (SE and total sleep time (TST. Intermittent light significantly increased objective alertness than dim light did during the second half of the light-exposure period. Our results suggested that intermittent light was as effective as continuous bright light in their acute effects in enhancing subjective and objective alertness and in negatively impacting subsequent sleep.

Time, not sleep, unbinds contexts from item memory.

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Roy Cox

Full Text Available Contextual cues are known to benefit memory retrieval, but whether and how sleep affects this context effect remains unresolved. We manipulated contextual congruence during memory retrieval in human volunteers across 12 h and 24 h intervals beginning with either sleep or wakefulness. Our data suggest that whereas contextual cues lose their potency with time, sleep does not modulate this process. Furthermore, our results are consistent with the idea that sleep's beneficial effect on memory retention depends on the amount of waking time that has passed between encoding and sleep onset. The findings are discussed in the framework of competitive consolidation theory.

Sleep duration and cancer risk: time to use a "sleep-years" index?

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Erren, Thomas C

2012-09-01

With a focus on melatonin, a recent paper in the Journal investigated the hypothesis that endometrial cancer might be associated with the duration, and ultimately, amount of sleep. The authors found that "[s]elf-reported sleep duration may not adequately represent melatonin levels." The authors also concluded that there was "weak evidence of an association between sleep duration and endometrial cancer risk." Overall, these are interesting observations because primarily experimental and mechanistic research from many angles supports the study's notion that inappropriate sleep may be a determinant of cancer risk. To find out whether this is so in man, rather than assigning study individuals to fixed or average "baseline sleep categories" i.e., ≤5, 6, 7, 8, ≥9 h of habitual sleep in the present study, the accumulated amount of sleep over decades should be reconstructed in retrospective or constructed in prospective studies. To achieve this end, future epidemiological studies may want to use a sleep-years index [SYI]. This simple exposure parameter promises to be a sensible, feasible, and affordable way to approximate cumulative time spent at sleep in critical time windows over many years which we should expect to be relevant for the development of cancer. The SYI could be tested and used in observational studies which promise to be comparable and can be merged. This commentary provides roots of the index and explains why and how it should be used and how it could be interpreted in rigorous studies of biologically plausible links between sleep, on the one hand, and the development of internal cancers, on the other. This commentary also points out limitations of interpreting the SYI. It is emphasized that, where possible, the SYI should be assessed independently of (a) other sleep facets--such as quality--and of (b) known or suspected cancer risk factors. The respective contribution of (a) and (b) to risk must then be assessed during the analyses. Overall, the

Primary sleep enuresis in childhood: polysomnography evidences of sleep stage and time modulation

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Rubens Reimäo

1993-03-01

Full Text Available The objective of this study was to evaluate enuretic events and its relations to sleep stages, sleep cycles and time durations in a selected group of children with primary essential sleep enuresis. We evaluated 18 patients with mean age of 8.2 years old (ranging from 5 to 12 years; 10 were males and 8 females (n.s.. They were referred to the Sleep Disorders Center with the specific complaint of enuresis since the first years of life (primary. Pediatric, urologic and neurologic workup did not show objective abnormalities (essential. The standard all-night polysomnography including an enuresis sensor attached to the shorts in the crotch area was performed. Only enuretic events nights were included. All were drug free patients for two weeks prior to polysomnography. In this report, only one polysomnography per patient was considered. The enuretic events were phase related, occurring predominantly in non-REM (NREM sleep (p<0.05. There was no predominance of enuretic events among the NREM stages (n.s.. A tendency of these events to occur in the first two sleep cycles was detected but may be due to the longer duration of these cycles. The events were time modulated, adjusted to a normal distribution with a mean of 213.4 min of recording time.

Effect of escitalopram combined with zolpidem on sleep structure, sleep process and neurotransmitter in elderly patients with chronic insomnia

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Ji-Peng Zhu

2016-12-01

Full Text Available Objective: To analyze the effect of escitalopram combined with zolpidem on sleep structure, sleep process and neurotransmitter in elderly patients with chronic insomnia. Methods: A total of 112 elderly patients with chronic insomnia treated in our hospital were included in the study and randomly divided into observation group and control group (n=56. Control group received zolpidem therapy alone, observation group received escitalopram combined with zolpidem therapy, and then differences in sleep structure and process, neurotransmitter, stress hormones, hypothalamus-pituitary-thyroid axis indexes and so on were compared between two groups of patients. Results: The sleep structure and sleep process parameters SL, RL and S2 levels of observation group after treatment were significantly lower than those of control group while TST, S3 and REM levels were significantly higher than those of control group; Orexin, ACTH, 5-HT, NE, CRH, E, AngⅡ, Cor, ALD, DA and TGA content in serum were significantly lower than those of control group while T3, T4, TSH and TRH content were significantly higher than those of control group. Conclusions: Escitalopram combined with zolpidem can optimize the sleep structure and process in elderly patients with chronic insomnia, and also plays a prominent role in regulating the body's homeostasis.

Effect of escitalopram combined with zolpidem on sleep structure, sleep process and neurotransmitter in elderly patients with chronic insomnia

Institute of Scientific and Technical Information of China (English)

Ji-Peng Zhu

2016-01-01

Objective:To analyze the effect of escitalopram combined with zolpidem on sleep structure, sleep process and neurotransmitter in elderly patients with chronic insomnia.Methods:A total of 112 elderly patients with chronic insomnia treated in our hospital were included in the study and randomly divided into observation group and control group (n=56). Control group received zolpidem therapy alone, observation group received escitalopram combined with zolpidem therapy, and then differences in sleep structure and process, neurotransmitter, stress hormones, hypothalamus-pituitary-thyroid axis indexes and so on were compared between two groups of patients.Results: The sleep structure and sleep process parameters SL, RL and S2 levels of observation group after treatment were significantly lower than those of control group while TST, S3 and REM levels were significantly higher than those of control group; Orexin, ACTH, 5-HT, NE, CRH, E, AngⅡ, Cor, ALD, DA and TGA content in serum were significantly lower than those of control group while T3, T4, TSH and TRH content were significantly higher than those of control group.Conclusions:Escitalopram combined with zolpidem can optimize the sleep structure and process in elderly patients with chronic insomnia, and also plays a prominent role in regulating the body's homeostasis.

Sleep Time: Media Hype vs. Diary Data

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Michelson, William

2011-01-01

Sleep duration has figured into claims of two trends promoted recently as dysfunctional in the mass media. One is the observation that the population at large is sleeping less than before. The second is that the annual change from Standard Time to Daylight Savings (or summer) Time causes adverse effects, largely through the loss of an hour's…

Sleep to the beat: A nap favours consolidation of timing.

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Verweij, Ilse M; Onuki, Yoshiyuki; Van Someren, Eus J W; Van der Werf, Ysbrand D

2016-06-01

Growing evidence suggests that sleep is important for procedural learning, but few studies have investigated the effect of sleep on the temporal aspects of motor skill learning. We assessed the effect of a 90-min day-time nap on learning a motor timing task, using 2 adaptations of a serial interception sequence learning (SISL) task. Forty-two right-handed participants performed the task before and after a 90-min period of sleep or wake. Electroencephalography (EEG) was recorded throughout. The motor task consisted of a sequential spatial pattern and was performed according to 2 different timing conditions, that is, either following a sequential or a random temporal pattern. The increase in accuracy was compared between groups using a mixed linear regression model. Within the sleep group, performance improvement was modeled based on sleep characteristics, including spindle- and slow-wave density. The sleep group, but not the wake group, showed improvement in the random temporal, but especially and significantly more strongly in the sequential temporal condition. None of the sleep characteristics predicted improvement on either general of the timing conditions. In conclusion, a daytime nap improves performance on a timing task. We show that performance on the task with a sequential timing sequence benefits more from sleep than motor timing. More important, the temporal sequence did not benefit initial learning, because differences arose only after an offline period and specifically when this period contained sleep. Sleep appears to aid in the extraction of regularities for optimal subsequent performance. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Direct Measurements of Smartphone Screen-Time: Relationships with Demographics and Sleep.

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Christensen, Matthew A; Bettencourt, Laura; Kaye, Leanne; Moturu, Sai T; Nguyen, Kaylin T; Olgin, Jeffrey E; Pletcher, Mark J; Marcus, Gregory M

2016-01-01

Smartphones are increasingly integrated into everyday life, but frequency of use has not yet been objectively measured and compared to demographics, health information, and in particular, sleep quality. The aim of this study was to characterize smartphone use by measuring screen-time directly, determine factors that are associated with increased screen-time, and to test the hypothesis that increased screen-time is associated with poor sleep. We performed a cross-sectional analysis in a subset of 653 participants enrolled in the Health eHeart Study, an internet-based longitudinal cohort study open to any interested adult (≥ 18 years). Smartphone screen-time (the number of minutes in each hour the screen was on) was measured continuously via smartphone application. For each participant, total and average screen-time were computed over 30-day windows. Average screen-time specifically during self-reported bedtime hours and sleeping period was also computed. Demographics, medical information, and sleep habits (Pittsburgh Sleep Quality Index-PSQI) were obtained by survey. Linear regression was used to obtain effect estimates. Total screen-time over 30 days was a median 38.4 hours (IQR 21.4 to 61.3) and average screen-time over 30 days was a median 3.7 minutes per hour (IQR 2.2 to 5.5). Younger age, self-reported race/ethnicity of Black and "Other" were associated with longer average screen-time after adjustment for potential confounders. Longer average screen-time was associated with shorter sleep duration and worse sleep-efficiency. Longer average screen-times during bedtime and the sleeping period were associated with poor sleep quality, decreased sleep efficiency, and longer sleep onset latency. These findings on actual smartphone screen-time build upon prior work based on self-report and confirm that adults spend a substantial amount of time using their smartphones. Screen-time differs across age and race, but is similar across socio-economic strata suggesting that

Direct Measurements of Smartphone Screen-Time: Relationships with Demographics and Sleep.

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Matthew A Christensen

Full Text Available Smartphones are increasingly integrated into everyday life, but frequency of use has not yet been objectively measured and compared to demographics, health information, and in particular, sleep quality.The aim of this study was to characterize smartphone use by measuring screen-time directly, determine factors that are associated with increased screen-time, and to test the hypothesis that increased screen-time is associated with poor sleep.We performed a cross-sectional analysis in a subset of 653 participants enrolled in the Health eHeart Study, an internet-based longitudinal cohort study open to any interested adult (≥ 18 years. Smartphone screen-time (the number of minutes in each hour the screen was on was measured continuously via smartphone application. For each participant, total and average screen-time were computed over 30-day windows. Average screen-time specifically during self-reported bedtime hours and sleeping period was also computed. Demographics, medical information, and sleep habits (Pittsburgh Sleep Quality Index-PSQI were obtained by survey. Linear regression was used to obtain effect estimates.Total screen-time over 30 days was a median 38.4 hours (IQR 21.4 to 61.3 and average screen-time over 30 days was a median 3.7 minutes per hour (IQR 2.2 to 5.5. Younger age, self-reported race/ethnicity of Black and "Other" were associated with longer average screen-time after adjustment for potential confounders. Longer average screen-time was associated with shorter sleep duration and worse sleep-efficiency. Longer average screen-times during bedtime and the sleeping period were associated with poor sleep quality, decreased sleep efficiency, and longer sleep onset latency.These findings on actual smartphone screen-time build upon prior work based on self-report and confirm that adults spend a substantial amount of time using their smartphones. Screen-time differs across age and race, but is similar across socio-economic strata

Sleep deprivation and injuries in part-time Kentucky farmers: impact of self reported sleep habits and sleep problems on injury risk.

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Spengler, Susan E; Browning, Steven R; Reed, Deborah B

2004-09-01

Part-time farmers who hold off-farm jobs may be at risk for injuries because of impaired performance resulting from inadequate sleep. For this study, 1004 part-time male Kentucky farmers completed a telephone interview for the 1994 to 1995 National Institute for Occupational Safety and Health-funded Farm Family Health and Hazard Surveillance Project. Questions were included about demographics, sleep habits, and injury occurrence. Twelve percent of the farmers reported an injury requiring medical intervention in the previous year. Farmers reported sleeping an average of 7.6 hours daily. Approximately 6.7% of the sample had three symptoms of sleep apnea. Although hours of sleep were not related to injury incidence, sleep medication use (odds ratio [OR] = 2.11, 95% confidence interval [CI] = 1.01 to 4.40) and presence of three sleep apnea symptoms (OR = 2.48, 95% CI = 1.13 to 5.41) were related to injury incidence. These data support the need for further research to examine sleep habits and promote strategies that reduce the risk for injuries caused by lack of sleep.

Adolescents' technology and face-to-face time use predict objective sleep outcomes.

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Tavernier, Royette; Heissel, Jennifer A; Sladek, Michael R; Grant, Kathryn E; Adam, Emma K

2017-08-01

The present study examined both within- and between-person associations between adolescents' time use (technology-based activities and face-to-face interactions with friends and family) and sleep behaviors. We also assessed whether age moderated associations between adolescents' time use with friends and family and sleep. Adolescents wore an actigraph monitor and completed brief evening surveys daily for 3 consecutive days. Adolescents (N=71; mean age=14.50 years old, SD=1.84; 43.7% female) were recruited from 3 public high schools in the Midwest. We assessed 8 technology-based activities (eg, texting, working on a computer), as well as time spent engaged in face-to-face interactions with friends and family, via questions on adolescents' evening surveys. Actigraph monitors assessed 3 sleep behaviors: sleep latency, sleep hours, and sleep efficiency. Hierarchical linear models indicated that texting and working on the computer were associated with shorter sleep, whereas time spent talking on the phone predicted longer sleep. Time spent with friends predicted shorter sleep latencies, while family time predicted longer sleep latencies. Age moderated the association between time spent with friends and sleep efficiency, as well as between family time and sleep efficiency. Specifically, longer time spent interacting with friends was associated with higher sleep efficiency but only among younger adolescents. Furthermore, longer family time was associated with higher sleep efficiency but only for older adolescents. Findings are discussed in terms of the importance of regulating adolescents' technology use and improving opportunities for face-to-face interactions with friends, particularly for younger adolescents. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

Accommodating adolescent sleep-wake patterns: the effects of shifting the timing of sleep on training effectiveness.

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Miller, Nita Lewis; Tvaryanas, Anthony P; Shattuck, Lawrence G

2012-08-01

This study evaluated the effect of accommodating adolescent sleep-wake patterns by altering the timing of the major sleep period of US Army recruits. The quasi-experimental study compared recruits assigned to one of two training companies: one with a customary sleep regimen (20:30 to 04:30) while the other employed a phase-delayed sleep regimen (23:00 to 07:00), the latter aligning better with biologically driven sleep-wake patterns of adolescents. The study was conducted during Basic Combat Training (BCT) at Fort Leonard Wood, Missouri. TRAINEES: The study included 392 trainees: 209 received the intervention, while 183 composed the Comparison group. Demographic and psychophysiological measures were collected on all trainees. Weekly assessments of subjective fatigue and mood, periodic physical fitness, marksmanship scores, and attrition rates from BCT were studied. Actigraphy was collected on approximately 24% of trainees. Based on actigraphy, trainees on the phase-delayed sleep schedule obtained 31 m more sleep/night than trainees on the customary sleep schedule. The Intervention group reported less total mood disturbance relative to baseline. Improvements in marksmanship correlated positively with average nightly sleep during the preceding week when basic marksmanship skills were taught. No differences were seen in physical fitness or attrition rates. In contrast to the Intervention group, the Comparison group was 2.3 times more likely to experience occupationally significant fatigue and 5.5 times more likely to report poor sleep quality. Accommodating adolescent sleep patterns significantly improves mental health and performance in the training environment.

Time delay between cardiac and brain activity during sleep transitions

NARCIS (Netherlands)

Long, X.; Arends, J.B.A.M.; Aarts, R.M.; Haakma, R.; Fonseca, P.; Rolink, J.

2015-01-01

Human sleep consists of wake, rapid-eye-movement (REM) sleep, and non-REM (NREM) sleep that includes light and deep sleep stages. This work investigated the time delay between changes of cardiac and brain activity for sleep transitions. Here, the brain activity was quantified by

Sleep, sleepiness and school start times: a preliminary study.

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Dexter, Donn; Bijwadia, Jagdeep; Schilling, Dana; Applebaugh, Gwendolyn

2003-01-01

High school students are reported to be excessively sleepy, resulting in decreased academic performance, increased psycho-social problems and increased risk of morbidity and mortality from accidents. Early school start times have been noted to contribute to this problem. This report attempts to confirm the relationship of early school start times with decreased sleep and increased sleepiness. We examined sophomore and junior students in 2 local high schools with different start times and measured the amount of time slept and sleepiness. We found that students at the early start school reported reduced sleep time and more sleepiness than their counterparts at the later starting school. Early school start times are associated with student reports of less sleep and increased sleepiness. Further studies in larger groups are recommended in view of the potential significant impact of sleep deprivation in this age group.

A Randomized Controlled Trial of Intensive Sleep Retraining (ISR): A Brief Conditioning Treatment for Chronic Insomnia

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Harris, Jodie; Lack, Leon; Kemp, Kristyn; Wright, Helen; Bootzin, Richard

2012-01-01

Study Objective: To investigate the effectiveness of intensive sleep retraining in comparison and combination with traditional behavioral intervention for chronic primary insomnia. Participants: Seventy-nine volunteers with chronic sleep-onset insomnia (with or without sleep maintenance difficulties) were randomly assigned either to intensive sleep retraining (ISR), stimulus control therapy (SCT), ISR plus SCT, or the control (sleep hygiene) treatment condition. Intervention: ISR treatment consisted of 50 sleep onset trials over a 25-h sleep deprivation period. Measurements and Results: Treatment response was assessed with sleep diary, activity monitoring, and questionnaire measures. The active treatment groups (ISR, SCT, ISR+SCT) all resulted in significant improvements in sleep onset latency and sleep efficiency, with moderate to large effect sizes from pre- to post-treatment. Wake time after sleep onset decreased significantly in the SCT and ISR+SCT groups. Total sleep time increased significantly in the ISR and ISR+SCT treatment groups. Participants receiving ISR (ISR, ISR+SCT) experienced rapidly improved SOL and TST during treatment, suggesting an advantage of rapid improvements in sleep in response to ISR. Although there were few statistically significant differences between groups on individual variables, ISR+SCT resulted in consistently larger effect sizes of change than other treatments, including questionnaire measures of sleep quality, sleep self-efficacy, and daytime functioning. The combination treatment group (ISR+SCT) showed trends to outperform other active treatment groups with fewer treatment dropouts, and a greater proportion of treatment responders with 61% reaching “good sleeper” status. Treatment gains achieved at post-treatment in the active treatment groups were largely maintained throughout follow-up periods to 6 months. Conclusion: This 25-hour intensive conditioning treatment for chronic insomnia can produce rapid improvements in

Adolescents' sleep in low-stress and high-stress (exam) times: a prospective quasi-experiment.

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Dewald, Julia F; Meijer, Anne Marie; Oort, Frans J; Kerkhof, Gerard A; Bögels, Susan M

2014-01-01

This prospective quasi-experiment (N = 175; mean age = 15.14 years) investigates changes in adolescents' sleep from low-stress (regular school week) to high-stress times (exam week), and examines the (moderating) role of chronic sleep reduction, baseline stress, and gender. Sleep was monitored over three consecutive weeks using actigraphy. Adolescents' sleep was more fragmented during the high-stress time than during the low-stress time, meaning that individuals slept more restless during stressful times. However, sleep efficiency, total sleep time, and sleep onset latency remained stable throughout the three consecutive weeks. High chronic sleep reduction was related to later bedtimes, later sleep start times, later sleep end times, later getting up times, and more time spent in bed. Furthermore, low chronic sleep reduction and high baseline stress levels were related to more fragmented sleep during stressful times. This study shows that stressful times can have negative effects on adolescents' sleep fragmentation, especially for adolescents with low chronic sleep reduction or high baseline stress levels.

Clusters of Insomnia Disorder: An Exploratory Cluster Analysis of Objective Sleep Parameters Reveals Differences in Neurocognitive Functioning, Quantitative EEG, and Heart Rate Variability

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Miller, Christopher B.; Bartlett, Delwyn J.; Mullins, Anna E.; Dodds, Kirsty L.; Gordon, Christopher J.; Kyle, Simon D.; Kim, Jong Won; D'Rozario, Angela L.; Lee, Rico S.C.; Comas, Maria; Marshall, Nathaniel S.; Yee, Brendon J.; Espie, Colin A.; Grunstein, Ronald R.

2016-01-01

Study Objectives: To empirically derive and evaluate potential clusters of Insomnia Disorder through cluster analysis from polysomnography (PSG). We hypothesized that clusters would differ on neurocognitive performance, sleep-onset measures of quantitative (q)-EEG and heart rate variability (HRV). Methods: Research volunteers with Insomnia Disorder (DSM-5) completed a neurocognitive assessment and overnight PSG measures of total sleep time (TST), wake time after sleep onset (WASO), and sleep onset latency (SOL) were used to determine clusters. Results: From 96 volunteers with Insomnia Disorder, cluster analysis derived at least two clusters from objective sleep parameters: Insomnia with normal objective sleep duration (I-NSD: n = 53) and Insomnia with short sleep duration (I-SSD: n = 43). At sleep onset, differences in HRV between I-NSD and I-SSD clusters suggest attenuated parasympathetic activity in I-SSD (P insomnia clusters derived from cluster analysis differ in sleep onset HRV. Preliminary data suggest evidence for three clusters in insomnia with differences for sustained attention and sleep-onset q-EEG. Clinical Trial Registration: Insomnia 100 sleep study: Australia New Zealand Clinical Trials Registry (ANZCTR) identification number 12612000049875. URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=347742. Citation: Miller CB, Bartlett DJ, Mullins AE, Dodds KL, Gordon CJ, Kyle SD, Kim JW, D'Rozario AL, Lee RS, Comas M, Marshall NS, Yee BJ, Espie CA, Grunstein RR. Clusters of Insomnia Disorder: an exploratory cluster analysis of objective sleep parameters reveals differences in neurocognitive functioning, quantitative EEG, and heart rate variability. SLEEP 2016;39(11):1993–2004. PMID:27568796

Relationships between school start time, sleep duration, and adolescent behaviors.

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Wahlstrom, Kyla L; Berger, Aaron T; Widome, Rachel

2017-06-01

The objectives were 2-fold: (1) to examine how high school start times relate to adolescent sleep duration, and (2) to test associations between sleep duration and mental health- and substance use-related issues and behaviors in teens. This study examines selected questions from survey data collected between 2010 and 2013 high school students. Respondents included more than 9000 students in grades 9 to 12 in 8 high schools in 5 school districts across the United States. The survey instrument is the 97-item Teen Sleep Habits Survey. Logistic regression models were used to calculate adjusted odds ratios and 95% confidence intervals. Because of clustering within schools and the use of repeated measures, generalized estimating equations were used to account for variance inflation. Greater sleep duration was associated with fewer reports of various mental health- and substance use-related issues and behaviors (all P values sleep reported, there was a 28% reduction in the adjusted odds of a participant reporting that he or she felt "unhappy, sad, or depressed." Later wake-up times were associated with a reduction in risk for some, but not all factors. Later start times were significantly associated with greater sleep duration. Given that later start times allow for greater sleep duration and that adequate sleep duration is associated with more favorable mental health- and substance use-related issues and behaviors, it is important that school districts prioritize exploring and implementing policies, such as delayed start times, that may increase the amount of sleep of adolescent students, which is needed for their optimal development. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

The suprachiasmatic nucleus regulates sleep timing and amount in mice

NARCIS (Netherlands)

Easton, Amy; Meerlo, Peter; Bergmann, Bernard; Turek, Fred W.

2004-01-01

Context: Sleep is regulated by circadian and homeostatic processes. The circadian pacemaker, located in the suprachiasmatic nuclei (SCN), regulates the timing and consolidation of the sleep-wake cycle, while a homeostatic mechanism governs the accumulation of sleep debt and sleep, recovery. Recent

The influence of school time on sleep patterns of children and adolescents.

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Carissimi, Alicia; Dresch, Fabiane; Martins, Alessandra Castro; Levandovski, Rosa Maria; Adan, Ana; Natale, Vincenzo; Martoni, Monica; Hidalgo, Maria Paz

2016-03-01

This epidemiological study evaluated the impact of school time on sleep parameters of children and adolescents. This cross-sectional study involved 639 elementary and high school students (mean age 13.03 years, range 8-18, 58.5% female) from the south of Brazil. Participants answered the Morningness-Eveningness Questionnaire (MEQ), and were asked about their sleeping habits on weekdays and weekends. Sleep deficit was defined as the difference between sleep duration on weekdays and weekends. The morning-school-time students presented significantly higher age, bedtime and wake up differences, sleep deficits, and social jetlag. The sleep deficit presented by girls was greater than that observed in boys of the same age. The difference between weekday and weekend waking times was also significantly greater in girls than in boys aged 13-18 years. Sleep deficit was significantly positively correlated with age and differences in wake up times, and significantly negatively correlated with MEQ scores, social jetlag, difference between weekday and weekend bedtimes, midpoint of sleep on weekends, and midpoint of sleep on weekends corrected for sleep deficit. A step-by-step multivariate logistic regression identified social jetlag, the difference between waking times on weekdays and weekends, and the midpoint of sleep on weekends as significant predictors of sleep deficit (Adjusted R(2) = 0.95; F = 1606.87; p school time influences the sleep parameters. The association of school schedules and physiological factors influence the sleep/wake cycle. Copyright © 2015 Elsevier B.V. All rights reserved.

The relationship between sleep and wake habits and academic performance in medical students: a cross-sectional study

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BaHammam Ahmed S

2012-08-01

Full Text Available Abstract Background The relationship between the sleep/wake habits and the academic performance of medical students is insufficiently addressed in the literature. This study aimed to assess the relationship between sleep habits and sleep duration with academic performance in medical students. Methods This study was conducted between December 2009 and January 2010 at the College of Medicine, King Saud University, and included a systematic random sample of healthy medical students in the first (L1, second (L2 and third (L3 academic levels. A self-administered questionnaire was distributed to assess demographics, sleep/wake schedule, sleep habits, and sleep duration. Daytime sleepiness was evaluated using the Epworth Sleepiness Scale (ESS. School performance was stratified as “excellent” (GPA ≥3.75/5 or “average” (GPA Results The final analysis included 410 students (males: 67%. One hundred fifteen students (28% had “excellent” performance, and 295 students (72% had “average” performance. The “average” group had a higher ESS score and a higher percentage of students who felt sleepy during class. In contrast, the “excellent” group had an earlier bedtime and increased TST during weekdays. Subjective feeling of obtaining sufficient sleep and non-smoking were the only independent predictors of “excellent” performance. Conclusion Decreased nocturnal sleep time, late bedtimes during weekdays and weekends and increased daytime sleepiness are negatively associated with academic performance in medical students.

Short Sleep Times Predict Obesity in Internal Medicine Clinic Patients

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Buscemi, Dolores; Kumar, Ashwani; Nugent, Rebecca; Nugent, Kenneth

2007-01-01

Study Objectives: Epidemiological studies have demonstrated an association between short sleep times and obesity as defined by body mass index (BMI). We wanted to determine whether this association occurs in patients with chronic medical diagnoses since the number of confounding factors is likely higher in patients than the general population. Methods: Two hundred patients attending internal medicine clinics completed a survey regarding sleep habits, lifestyle characteristics, and medical diagnoses. An independent surveyor collected the information on the questionnaires and reviewed the medical records. Height and weight were measured by clinic personnel. Data were analyzed with multivariate logistic regression. Results: Subjects with short sleep times (< 7 hours) had an increased likelihood of obesity as defined by a BMI ≥ 30 kg/m2 when compared to the reference group of (8, 9] hours (odds ratio 2.93; 95% confidence interval, 1.06–8.09). There was a U-shaped relationship between obesity and sleep time in women but not in men. Young age (18 to 49 years), not smoking, drinking alcohol, hypertension, diabetes, and sleep apnea were also associated with obesity in the overall model. Conclusions: This study demonstrates an association between short sleep times and obesity in undifferentiated patients attending an internal medicine clinic using models adjusting for age, lifestyle characteristics, and some medical diagnoses. The U-shaped relationship in women suggests that sleep patterns may have gender specific associations. These observations provide the background for therapeutic trials in weight loss in patients with established medical problems. Citation: Buscemi D; Kumar A; Nugent R; Nugent K. Short sleep times predict obesity in internal medicine clinic patients. J Clin Sleep Med 2007;3(7):681–688. PMID:18198800

The longer the better: Sleep-wake patterns during preparation of the World Rowing Junior Championships.

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Kölling, Sarah; Steinacker, Jürgen M; Endler, Stefan; Ferrauti, Alexander; Meyer, Tim; Kellmann, Michael

2016-01-01

Recovery is essential for high athletic performance, and therefore especially sleep has been identified as a crucial source for physical and psychological well-being. However, due to early-morning trainings, which are general practice in many sports, athletes are likely to experience sleep restrictions. Therefore, this study investigated the sleep-wake patterns of 55 junior national rowers (17.7 ± 0.6 years) via sleep logs and actigraphy during a four-week training camp. Recovery and stress ratings were obtained every morning with the Short Recovery and Stress Scale on a 7-point Likert-type scale ranging from 0 (does not apply at all) to 6 (fully applies). The first training session was scheduled for 6:30 h every day. With two to four training sessions per day, the training load was considerably increased from athletes' home training. Objective sleep measures (n = 14) revealed less total sleep time (TST) in the first two weeks (409.6 ± 19.1 and 416.0 ± 16.3 min), while training volume and intensity were higher. In the second half of the camp, less training sessions were implemented, more afternoons were training free and TSTs were longer (436.3 ± 15.8 and 456.9 ± 25.7 min). A single occasion of 1.5-h delayed bedtime and usual early morning training (6:30 h) resulted in reduced ratings of Overall Recovery (OR) (M = 3.3 ± 1.3) and greater Negative Emotional State (NES) (M = 1.3 ± 1.2, p sleep-offset times were shifted from ~5:30 to ~8:00 h, and each recovery and stress score improved (p sleep and recovery. Intercorrelations of these sleep parameters emphasised the relationship between restful sleep and falling asleep quickly (r = .34, p sleep on subjective recovery measures in the setting of a training camp. Providing the opportunity of extended sleep (and a day off) seems the most simple and effective strategy to enhance recovery and stress-related ratings.

Measurement of ion temperature and flow in RF start-up plasmas in TST-2 and LATE

International Nuclear Information System (INIS)

Tsuda, Shintaro; Ejiri, Akira; Takase, Yuichi; Tsujii, Naoto; Takeuchi, Toshihiro; Tanaka, Hitoshi; Uchida, Masaki; Maekawa, Takashi

2015-01-01

The ion temperature and flow of RF start-up plasmas in TST-2 and LATE were measured using a visible spectrometer. The plasma currents were 9 kA and 8 kA, respectively. The typical ion temperatures T i and toroidal flow V ϕ were 4 eV and 1 km/s, respectively, in the TST-2 plasma sustained by the lower hybrid wave (20 kW) and T i ∼ 10 eV and V ϕ ∼ 5 km/s in the LATE plasma sustained by the electron cyclotron wave (50 kW). The poloidal flow velocities were comparable to the toroidal velocities. The ion temperatures were relatively high and the ion orbit loss can be significant. (author)

Acute physical exercise under hypoxia improves sleep, mood and reaction time.

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de Aquino-Lemos, Valdir; Santos, Ronaldo Vagner T; Antunes, Hanna Karen Moreira; Lira, Fabio S; Luz Bittar, Irene G; Caris, Aline V; Tufik, Sergio; de Mello, Marco Tulio

2016-02-01

This study aimed to assess the effect of two sessions of acute physical exercise at 50% VO2peak performed under hypoxia (equivalent to an altitude of 4500 m for 28 h) on sleep, mood and reaction time. Forty healthy men were randomized into 4 groups: Normoxia (NG) (n = 10); Hypoxia (HG) (n = 10); Exercise under Normoxia (ENG) (n = 10); and Exercise under Hypoxia (EHG) (n = 10). All mood and reaction time assessments were performed 40 min after awakening. Sleep was reassessed on the first day at 14 h after the initiation of hypoxia; mood and reaction time were measured 28 h later. Two sessions of acute physical exercise at 50% VO2peak were performed for 60 min on the first and second days after 3 and 27 h, respectively, after starting to hypoxia. Improved sleep efficiency, stage N3 and REM sleep and reduced wake after sleep onset were observed under hypoxia after acute physical exercise. Tension, anger, depressed mood, vigor and reaction time scores improved after exercise under hypoxia. We conclude that hypoxia impairs sleep, reaction time and mood. Acute physical exercise at 50% VO2peak under hypoxia improves sleep efficiency, reversing the aspects that had been adversely affected under hypoxia, possibly contributing to improved mood and reaction time.

Sleep restriction and degraded reaction-time performance in Figaro solo sailing races.

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Hurdiel, Rémy; Van Dongen, Hans P A; Aron, Christophe; McCauley, Peter; Jacolot, Laure; Theunynck, Denis

2014-01-01

In solo offshore sailing races like those of the Solitaire du Figaro, sleep must be obtained in multiple short bouts to maintain competitive performance and safety. Little is known about the amount of sleep restriction experienced at sea and the effects that fatigue from sleep loss have on sailors' performance. Therefore, we assessed sleep in sailors of yachts in the Figaro 2 Beneteau class during races and compared response times on a serial simple reaction-time test before and after races. Twelve men (professional sailors) recorded their sleep and measured their response times during one of the three single-handed races of 150, 300 and 350 nautical miles (nominally 24-50 h in duration). Total estimated sleep duration at sea indicated considerable sleep insufficiency. Response times were slower after races than before. The results suggest that professional sailors incur severe sleep loss and demonstrate marked performance impairment when competing in one- to two-day solo sailing races. Competitive performance could be improved by actively managing sleep during solo offshore sailing races.

Time delay between cardiac and brain activity during sleep transitions

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Long, Xi; Arends, Johan B.; Aarts, Ronald M.; Haakma, Reinder; Fonseca, Pedro; Rolink, Jérôme

2015-04-01

Human sleep consists of wake, rapid-eye-movement (REM) sleep, and non-REM (NREM) sleep that includes light and deep sleep stages. This work investigated the time delay between changes of cardiac and brain activity for sleep transitions. Here, the brain activity was quantified by electroencephalographic (EEG) mean frequency and the cardiac parameters included heart rate, standard deviation of heartbeat intervals, and their low- and high-frequency spectral powers. Using a cross-correlation analysis, we found that the cardiac variations during wake-sleep and NREM sleep transitions preceded the EEG changes by 1-3 min but this was not the case for REM sleep transitions. These important findings can be further used to predict the onset and ending of some sleep stages in an early manner.

Insomnia Patients With Objective Short Sleep Duration Have a Blunted Response to Cognitive Behavioral Therapy for Insomnia.

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Bathgate, Christina J; Edinger, Jack D; Krystal, Andrew D

2017-01-01

This study examined whether individuals with insomnia and objective short sleep duration insomnia (CBT-I) when compared to individuals with insomnia and normal sleep duration ≥6 h. Secondary analyses of a randomized, clinical trial with 60 adult participants (n = 31 women) from a single academic medical center. Outpatient treatment lasted 8 weeks, with a final follow-up conducted at 6 months. Mixed-effects models controlling for age, sex, CBT-I treatment group assignment, and treatment provider examined sleep parameters gathered via actigraphy, sleep diaries, and an Insomnia Symptom Questionnaire (ISQ) across the treatment and follow-up period. Six months post-CBT-I treatment, individuals with insomnia and normal sleep duration ≥6 h fared significantly better on clinical improvement milestones than did those with insomnia and short sleep duration insomnia and normal sleep duration had significantly higher insomnia remission (ISQ 80%; χ2[1, N = 60] = 21, p 50% decline in MWASO (χ2[1, N = 60] = 60, p insomnia and short sleep duration. Additionally, those with insomnia and normal sleep duration had more success decreasing their total wake time (TWT) at the 6-month follow-up compared to those with insomnia and short sleep duration (χ2[2, N = 60] = 44.1, p insomnia remission, with the area under the curve = 0.986. Findings suggest that individuals with insomnia and objective short sleep duration insomnia and normal sleep duration ≥6 h. Using an actigraphy TST cutoff of 6 hours to classify sleep duration groups was highly accurate and provided good discriminant value for determining insomnia remission. © Sleep Research Society 2016. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Circadian adaptation of airline pilots during extended duration operations between the USA and Asia.

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Gander, Philippa; van den Berg, Margo; Mulrine, Hannah; Signal, Leigh; Mangie, Jim

2013-10-01

This study tracked circadian adaptation among airline pilots before, during, and after trips where they flew from Seattle (SEA) or Los Angeles (LAX) to Asia (7--9 time zones westward), spent 7--12 d in Asia, and then flew back to the USA. In Asia, pilots' exposures to local time cues and sleep opportunities were constrained by duty (short-haul flights crossing ≤ 1 time zone/24 h). Fourteen captains and 16 first officers participated (median age = 56 versus 48 yrs, p.U) < 0.001). Their sleep was monitored (actigraphy, duty/sleep diaries) from 3 d pre-trip to 5 d post-trip. For every flight, Karolinska Sleepiness and Samn-Perelli Fatigue scales and 5-min psychomotor vigilance task (PVT) tests were completed pre-flight and at top of descent (TOD). Participants had ≥ 3 d free of duty prior to outbound flight(s). From 72--24 h prior to departure (baseline sleep), mean total sleep/24 h (TST) = 7.00 h (SD = 1.18 h) and mean sleep efficiency = 87% (SD = 4.9%). Most pilots (23/30) flew direct to and from Asia, but 7 LAX-based pilots flew via a 1-d layover in Honolulu (HNL). On flights with ≥ 2 pilots, mean total in-flight sleep varied from 0.40 to 2.09 h outbound and from 0.74 to 1.88 h inbound. Duty patterns in Asia were variable, with ≤ 2 flights/d (mean flight duration = 3.53 h, SD = 0.53 h). TST on days 17 in Asia did not differ from baseline (p.F) = 0.2031). However, mean sleep efficiency was significantly lower than baseline on days 5--7 (p.F) = 0.0041). More pilots were on duty between 20:00 and 24:00 h on days 57 (mean = 21%) than on days 24 (mean = 14%). Sleep propensity distribution phase markers and chi-square periodogram analyses suggest that adaptation to local time was complete by day 4 in Asia. On pre-flight PVT tests in Asia, the slowest 10% of responses improved for flights departing 14:00--19:59 h (p.F) = 0.0484). At TOD, the slowest 10% of responses improved across days for flights arriving 14:00--19:59 h (p.F) = 0.0349) and 20:00--01:59 h (p

The validity of Actiwatch2 and SenseWear armband compared against polysomnography at different ambient temperature conditions

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Mirim Shin

2015-01-01

Full Text Available There were no validation studies on portable sleep devices under different ambient temperature, thus this study evaluated the validity of wrist Actiwatch2 (AW2 or SenseWear armband (SWA against polysomnography (PSG in different ambient temperatures. Nine healthy young participants (6 males, aged 23.3±4.1 y underwent nine nights of study at ambient temperature of 17 °C, 22 °C and 29 °C in random order, after an adaptation night. They wore the AW2 and SWA while being monitored for PSG simultaneously. A linear mixed model indicated that AW2 is valid for sleep onset latency (SOL, total sleep time (TST and sleep efficiency (SE but significantly overestimated wake after sleep onset (WASO at 17 °C and 22 °C. SWA is valid for WASO, TST and SE at these temperatures, but severely underestimates SOL. However, at 29 °C, SWA significantly overestimated WASO and underestimated TST and SE. Bland–Altman plots showed small biases with acceptable limits of agreement (LoA for AW2 whereas, small biases and relatively wider LoA for most sleep variables were observed in SWA. The kappa statistic showed a moderate sleep–wake epoch agreement, with a high sensitivity but poor specificity; wake detection remains suboptimal. AW2 showed small biases for most of sleep variables at all temperature conditions, except for WASO. SWA is reliable for measures of TST, WASO and SE at 17–22 °C but not at 29 °C, and SOL approximates that of PSG only at 29 °C, thus caution is needed when monitoring sleep at different temperatures, especially in home sleep studies, in which temperature conditions are more variable.

Mental time travel to the future might be reduced in sleep.

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Speth, Jana; Schloerscheidt, Astrid M; Speth, Clemens

2017-02-01

We present a quantitative study of mental time travel to the future in sleep. Three independent, blind judges analysed a total of 563 physiology-monitored mentation reports from sleep onset, REM sleep, non-REM sleep, and waking. The linguistic tool for the mentation report analysis is based on established grammatical and cognitive-semantic theories and has been validated in previous studies. Our data indicate that REM and non-REM sleep must be characterized by a reduction in mental time travel to the future, which would support earlier physiological evidence at the level of brain function. Copyright © 2016 Elsevier Inc. All rights reserved.

Sleepy Teens and Energy Drink Use: Results From an Ethnically Diverse Sample of Youth.

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Troxel, Wendy M; Tucker, Joan S; Ewing, Brett; Miles, Jeremy N V; D'Amico, Elizabeth J

2018-01-01

This study examines the association between use of energy drinks or products (EP), EP expectancies, and the association between EP use and sleep in a racially and ethnically diverse sample (N = 2,485) of adolescents. Prevalence of EP use was approximately 18%, with no statistically significant racial or ethnic differences in prevalence. There were significant racial and ethnic differences in EP expectancies; Hispanic and Multiracial or Other groups endorsed less positive expectancies than Whites and Asians. EP use was significantly associated with later weekend bedtimes, shorter weekend total sleep time (TST), a smaller weekend-weekday difference in TST, and more trouble sleeping, even after adjusting for covariates. There were no significant race or ethnicity interactions between EP use and sleep. EP use is an independent correlate of sleep problems in adolescents across racial or ethnic groups.

Relationship between Travel Time from Home to a Regional Sleep Apnea Clinic in British Columbia, Canada, and the Severity of Obstructive Sleep.

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Allen, A J M Hirsch; Amram, Ofer; Tavakoli, Hamid; Almeida, Fernanda R; Hamoda, Mona; Ayas, Najib T

2016-05-01

In the majority of people with obstructive sleep apnea, the disorder remains undiagnosed. This may be partly a result of inadequate access to diagnostic sleep services. We thus hypothesized that even modest travel times to a sleep clinic may delay diagnosis and reduce detection of milder disease. We sought to determine whether travel time between an individual's home and a sleep clinic is associated with sleep apnea severity at presentation. We recruited patients referred for suspected sleep apnea to the University of British Columbia Hospital Sleep Clinic between May 2003 and July 2011. The patient's place of residence was geocoded at the postal code level. Travel times between the population-weighted dissemination areas for each patient and the sleep clinic were calculated using ArcGIS (ESRI, Redlands, CA) network analyst and the Origin-Destination matrix function. All patients underwent full polysomnography. There were 1,275 patients; 69% were male, the mean age was 58 years. (SD = 11.9), and the mean apnea-hypopnea index was 22 per hour (SD = 21.6). In the univariate model, travel time was a significant predictor of obstructive sleep apnea severity (P = 0.02). After controlling for confounders including sex, age, obesity, and education, travel time remained a significant predictor of sleep apnea severity (P travel time was associated with an increase in the apnea-hypopnea index of 1.4 events per hour. For reasons that remain to be determined, travel times are associated with the severity of obstructive sleep apnea at presentation to a sleep clinic. If the results can be verified at other centers, this may help guide the geographic distribution of sleep centers within a health care system.

Circadian activity rhythms for mothers with an infant in ICU

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Shih-Yu eLee

2010-12-01

Full Text Available Circadian rhythms influence sleep and wakefulness. Circadian activity rhythms (CAR are altered in individuals with dementia or seasonal affective disorder. To date, studies exploring CAR and sleep in postpartum women are rare. The purpose of this report is to describe relationships between CAR, sleep disturbance, and fatigue among 72 first-time mothers during their 2nd week postpartum while their newborn remain hospitalized in intensive care unit (ICU. Seventy two mothers were included in this secondary data analysis sample from three separate studies. Participants completed the General Sleep Disturbance Scale (GSDS, Numerical Rating Scale for Fatigue (NRS-F, and a sleep diary. The objective sleep data included total sleep time (TST, wake after sleep onset (WASO, and CAR determined by the circadian quotient (amplitude/mesor averaged from at least 48-hours of wrist actigraphy monitoring. The TST of mothers who self-reported as poor sleepers was 354 minutes (SEM= 21.9, with a mean WASO of 19.5% (SEM= 2.8. The overall sleep quality measured by the GSDS was clinically, significantly disrupted (M= 5.5, SD= 1.2. The mean score for morning fatigue was 5.8 (SD= 2.0, indicating moderate fatigue severity. The CAR was .62 (SEM= .04, indicating poor synchronization. The self-reported good sleepers (GSDS < 3 had better CAR (M= .71, SEM= .02 than poor sleepers (GSDS > 3 (t [70] = 2.0, p< .05. A higher circadian equation was associated with higher TST (r= .83, p<.001, less WASO (r= -.50, p< .001, lower self-reported sleep disturbance scores (r= -.35, p= .01, and less morning fatigue (r= -.26. Findings indicate that mothers with a hospitalized infant have both nocturnal sleep problems and disturbed circadian activity rhythms. Factors responsible for these sleep and rhythm disturbances, the adverse effects on mother’s physical and mental well-being, and mother-infant relationship require further study.

Impact of the Regulators SigB, Rot, SarA and sarS on the Toxic Shock Tst Promoter and TSST-1 Expression in Staphylococcus aureus.

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Diego O Andrey

Full Text Available Staphylococcus aureus is an important pathogen manifesting virulence through diverse disease forms, ranging from acute skin infections to life-threatening bacteremia or systemic toxic shock syndromes. In the latter case, the prototypical superantigen is TSST-1 (Toxic Shock Syndrome Toxin 1, encoded by tst(H, and carried on a mobile genetic element that is not present in all S. aureus strains. Transcriptional regulation of tst is only partially understood. In this study, we dissected the role of sarA, sarS (sarH1, RNAIII, rot, and the alternative stress sigma factor sigB (σB. By examining tst promoter regulation predominantly in the context of its native sequence within the SaPI1 pathogenicity island of strain RN4282, we discovered that σB emerged as a particularly important tst regulator. We did not detect a consensus σB site within the tst promoter, and thus the effect of σB is likely indirect. We found that σB strongly repressed the expression of the toxin via at least two distinct regulatory pathways dependent upon sarA and agr. Furthermore rot, a member of SarA family, was shown to repress tst expression when overexpressed, although its deletion had no consistent measurable effect. We could not find any detectable effect of sarS, either by deletion or overexpression, suggesting that this regulator plays a minimal role in TSST-1 expression except when combined with disruption of sarA. Collectively, our results extend our understanding of complex multifactorial regulation of tst, revealing several layers of negative regulation. In addition to environmental stimuli thought to impact TSST-1 production, these findings support a model whereby sporadic mutation in a few key negative regulators can profoundly affect and enhance TSST-1 expression.

Sleep restriction may lead to disruption in physiological attention and reaction time

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Arbind Kumar Choudhary

2016-07-01

Full Text Available Sleepiness is the condition where for some reason fails to go into a sleep state and will have difficulty in remaining awake even while carrying out activities. Sleep restriction occurs when an individual fails to get enough sleep due to high work demands. The mechanism between sleep restriction and underlying brain physiology deficits is not well assumed. The objective of the present study was to investigate the mental attention (P300 and reaction time [visual (VRT and auditory (ART] among night watchmen, at subsequent; first (1st day, fourth (4th day and seventh (7th day of restricted sleep period. After exclusion and inclusion criteria, the study was performed among 50 watchmen (age=18–35 years (n=50 after providing written informed consent and divided into two group. Group I-(Normal sleep (n=28 working in day time and used to have normal sleep in night (≥8 h; Group II-(Restricted sleep (n=22 - working in night time and used to have less sleep in night (≤3 h. Statistical significance between the different groups was determined by the independent student ʻtʼ test and the significance level was fixed at p≤0.05. We observed that among all normal and restricted sleep watchmen there was not any significant variation in Karolinska Sleepiness Scale (KSS score, VRT and ART, along with latency and amplitude of P300 on 1st day of restricted sleep. However at subsequent on 4th day and 7th day of restricted sleep, there was significant increase in (KSSscore, and prolongation of VRT and ART as well as alteration in latency and amplitude of P300 wave in restricted sleep watchmen when compare to normal sleep watchmen. The present finding concludes that loss of sleep has major impact in dynamic change in mental attention and reaction time among watchmen employed in night shift. Professional regulations and work schedules should integrate sleep schedules before and during the work period as an essential dimension for their healthy life.

Sleep restriction may lead to disruption in physiological attention and reaction time.

Science.gov (United States)

Choudhary, Arbind Kumar; Kishanrao, Sadawarte Sahebrao; Dadarao Dhanvijay, Anup Kumar; Alam, Tanwir

2016-01-01

Sleepiness is the condition where for some reason fails to go into a sleep state and will have difficulty in remaining awake even while carrying out activities. Sleep restriction occurs when an individual fails to get enough sleep due to high work demands. The mechanism between sleep restriction and underlying brain physiology deficits is not well assumed. The objective of the present study was to investigate the mental attention (P300) and reaction time [visual (VRT) and auditory (ART)] among night watchmen, at subsequent; first (1st) day, fourth (4th) day and seventh (7th) day of restricted sleep period. After exclusion and inclusion criteria, the study was performed among 50 watchmen (age=18-35 years) (n=50) after providing written informed consent and divided into two group. Group I-(Normal sleep) (n=28) working in day time and used to have normal sleep in night (≥8 h); Group II-(Restricted sleep) (n=22) - working in night time and used to have less sleep in night (≤3 h). Statistical significance between the different groups was determined by the independent student ' t ' test and the significance level was fixed at p≤0.05. We observed that among all normal and restricted sleep watchmen there was not any significant variation in Karolinska Sleepiness Scale (KSS) score, VRT and ART, along with latency and amplitude of P300 on 1st day of restricted sleep. However at subsequent on 4th day and 7th day of restricted sleep, there was significant increase in (KSS)score, and prolongation of VRT and ART as well as alteration in latency and amplitude of P300 wave in restricted sleep watchmen when compare to normal sleep watchmen. The present finding concludes that loss of sleep has major impact in dynamic change in mental attention and reaction time among watchmen employed in night shift. Professional regulations and work schedules should integrate sleep schedules before and during the work period as an essential dimension for their healthy life.

Associations of sedentary time and moderate-vigorous physical activity with sleep-disordered breathing and polysomnographic sleep in community-dwelling adults.

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Kline, Christopher E; Krafty, Robert T; Mulukutla, Suresh; Hall, Martica H

2017-05-01

The purpose of this study was to evaluate the relationship between daytime activity (sedentary time, moderate- to vigorous-intensity physical activity [MVPA]) and indices of polysomnographically (PSG) assessed sleep, including sleep-disordered breathing (SDB). One hundred and thirty-six adults (65% female, 59.8 ± 9.1 years, body mass index [BMI] 30.3 ± 6.9 kg m -2 ) provided daily estimates of time spent in light-, moderate-, and vigorous-intensity activity for 6-14 days (mean 9.9 ± 1.8 days) prior to laboratory PSG. Daily sedentary time was calculated as the amount of time spent awake and not in light-, moderate-, or vigorous-intensity activity; time spent in moderate- and vigorous-intensity activity were combined for MVPA. Indices of PSG sleep included timing (sleep midpoint), duration (total sleep time), continuity (sleep efficiency), depth (% slow-wave sleep), and SDB (apnea-hypopnea index [AHI]). Using median splits of sedentary time and MVPA, analyses of covariance examined their relationship with sleep following adjustment for age, sex, race, employment, education, BMI, existing cardiovascular disease, depression history, and mean daily wake time. Binary logistic regression examined the odds of having at least mild-severity SDB (AHI ≥ 5) according to sedentary time, MVPA, and their combination. Adults with above-median sedentary time (i.e., >841.9 min/day) had significantly greater AHI (P = .04) and lower odds of mild SDB (P = .03) compared to adults with low sedentary time; adults with high MVPA (>30.5 min/day) had significantly lower AHI compared to adults with low MVPA (P = .04). When examined in the same model, adults with high sedentary time and low MVPA had significantly higher AHI (P < .01) and higher odds of having mild SDB (P = .03) than all the other groups. No other sleep measures were related to sedentary time, MVPA, or their combination. Sedentary time and MVPA were associated with SDB. Whether reducing sedentary

Light-cone reduction vs. TsT transformations: a fluid dynamics perspective

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Dutta, Suvankar; Krishna, Hare

2018-05-01

We compute constitutive relations for a charged (2+1) dimensional Schrödinger fluid up to first order in derivative expansion, using holographic techniques. Starting with a locally boosted, asymptotically AdS, 4 + 1 dimensional charged black brane geometry, we uplift that to ten dimensions and perform TsT transformations to obtain an effective five dimensional local black brane solution with asymptotically Schrödinger isometries. By suitably implementing the holographic techniques, we compute the constitutive relations for the effective fluid living on the boundary of this space-time and extract first order transport coefficients from these relations. Schrödinger fluid can also be obtained by reducing a charged relativistic conformal fluid over light-cone. It turns out that both the approaches result the same system at the end. Fluid obtained by light-cone reduction satisfies a restricted class of thermodynamics. Here, we see that the charged fluid obtained holographically also belongs to the same restricted class.

Middle school start times: the importance of a good night's sleep for young adolescents.

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Wolfson, Amy R; Spaulding, Noah L; Dandrow, Craig; Baroni, Elizabeth M

2007-01-01

With the onset of adolescence, teenagers require 9.2 hr of sleep and experience a delay in the timing of sleep. In the "real world" with early school start times, however, they report less sleep, striking differences between their school-weekend sleep schedules, and significant daytime sleepiness. Prior studies demonstrated that high schoolers with later school starts do not further delay bedtime but obtain more sleep due to later wake times. This study examined sleep-wake patterns of young adolescents attending urban, public middle schools with early (7:15 a.m.) versus late (8:37 a.m.) start times. Students (N = 205) were assessed at 2 time periods. Students at the late-starting school reported waking up over 1 hr later on school mornings and obtaining 50 min more sleep each night, less sleepiness, and fewer tardies than students at the early school. All students reported similar school-night bedtime, sleep hygiene practices, and weekend sleep schedules.

Impact of delaying school start time on adolescent sleep, mood, and behavior.

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Owens, Judith A; Belon, Katherine; Moss, Patricia

2010-07-01

To examine the impact of a 30-minute delay in school start time on adolescents' sleep, mood, and behavior. Participants completed the online retrospective Sleep Habits Survey before and after a change in school start time. An independent high school in Rhode Island. Students (n = 201) in grades 9 through 12. Intervention Institution of a delay in school start time from 8 to 8:30 am. Sleep patterns and behavior, daytime sleepiness, mood, data from the Health Center, and absences/tardies. After the start time delay, mean school night sleep duration increased by 45 minutes, and average bedtime advanced by 18 minutes (95% confidence interval, 7-29 minutes [t(423) = 3.36; P students getting less than 7 hours of sleep decreased by 79.4%, and those reporting at least 8 hours of sleep increased from 16.4% to 54.7%. Students reported significantly more satisfaction with sleep and experienced improved motivation. Daytime sleepiness, fatigue, and depressed mood were all reduced. Most health-related variables, including Health Center visits for fatigue-related complaints, and class attendance also improved. A modest delay in school start time was associated with significant improvements in measures of adolescent alertness, mood, and health. The results of this study support the potential benefits of adjusting school schedules to adolescents' sleep needs, circadian rhythm, and developmental stage.

Plasma current start-up experiments without the central solenoid in the TST-2 spherical tokamak

International Nuclear Information System (INIS)

Takase, Y.; Ejiri, A.; Shiraiwa, S.; Adachi, Y.; Ishii, N.; Kasahara, H.; Nuga, H.; Ono, Y.; Oosako, T.; Sasaki, M.; Shimada, Y.; Sumitomo, N.; Taguchi, I.; Tojo, H.; Tsujimura, J.; Ushigome, M.; Yamada, T.; Hanada, K.; Hasegawa, M.; Idei, H.; Nakamura, K.; Sakamoto, M.; Sasaki, K.; Sato, K.N.; Zushi, H.; Nishino, N.; Mitarai, O.

2006-01-01

Several techniques for initiating the plasma current without the use of the central solenoid are being developed in TST-2. While TST-2 was temporarily located at Kyushu University, two types of start-up scenarios were demonstrated. (1) A plasma current of 4 kA was generated and sustained for 0.28 s by either electron cyclotron wave or electron Bernstein wave, without induction. (2) A plasma current of 10 kA was obtained transiently by induction using only outboard poloidal field coils. In the second scenario, it is important to supply sufficient power for ionization (100 kW of EC power was sufficient in this case), since the vertical field during start-up is not adequate to maintain plasma equilibrium. In addition, electron heating experiments using the X-B mode conversion scenario were performed, and a heating efficiency of 60% was observed at a 100 kW RF power level. TST-2 is now located at the Kashiwa Campus of the University of Tokyo. Significant upgrades were made in both magnetic coil power supplies and RF systems, and plasma experiments have restarted. RF power of up to 400 kW is available in the high-harmonic fast wave frequency range around 20 MHz. Four 200 MHz transmitters are now being prepared for plasma current start-up experiments using RF power in the lower-hybrid frequency range. Preparations are in progress for a new plasma merging experiment (UTST) aimed at the formation and sustainment of ultra-high β ST plasmas

Time Alignment as a Necessary Step in the Analysis of Sleep Probabilistic Curves

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Rošt'áková, Zuzana; Rosipal, Roman

2018-02-01

Sleep can be characterised as a dynamic process that has a finite set of sleep stages during the night. The standard Rechtschaffen and Kales sleep model produces discrete representation of sleep and does not take into account its dynamic structure. In contrast, the continuous sleep representation provided by the probabilistic sleep model accounts for the dynamics of the sleep process. However, analysis of the sleep probabilistic curves is problematic when time misalignment is present. In this study, we highlight the necessity of curve synchronisation before further analysis. Original and in time aligned sleep probabilistic curves were transformed into a finite dimensional vector space, and their ability to predict subjects' age or daily measures is evaluated. We conclude that curve alignment significantly improves the prediction of the daily measures, especially in the case of the S2-related sleep states or slow wave sleep.

TST, as a polysomnographic variable, is superior to the apnea hypopnea index for evaluating intermittent hypoxia in severe obstructive sleep apnea.

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Zhang, Xiao-Bin; Zen, Hui-Qing; Lin, Qi-Chang; Chen, Gong-Ping; Chen, Li-Da; Chen, Hua

2014-10-01

The polysomnography (PSG) index of the apnea hypopnea index (AHI) is considered the 'gold standard' for stratifying the severity of obstructive sleep apnea (OSA). However, AHI cannot reflect the true characteristic of chronic intermittent hypoxia (CIH), which may trigger systemic inflammation in some OSA patients. High-sensitivity C-reactive protein (hsCRP) is considered a biomarker of systemic inflammation in OSA patients. The aim of the present study was to evaluate the relationship between PSG variables and hsCRP in men with severe OSA. Men with severe OSA (AHI ≥ 30 events/h) diagnosed by PSG were enrolled. AHI and body mass index were matched between a high hsCRP group (hsCRP ≥ 3.0 mg/L) and a low hsCRP group. A blood sample was taken for serum hsCRP analysis. Multiple regression analysis was performed to assess independent predictors of high hsCRP. One hundred and fifty-two subjects were enrolled in the study (76 in each group). Mean serum hsCRP was 3.76 ± 2.13 mg/L. The mean percentage of total sleep time spent with SaO2 hypoxia variables.

Later Start, Longer Sleep: Implications of Middle School Start Times

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Temkin, Deborah A.; Princiotta, Daniel; Ryberg, Renee; Lewin, Daniel S.

2018-01-01

Background: Although adolescents generally get less than the recommended 9 hours of sleep per night, research and effort to delay school start times have generally focused on high schools. This study assesses the relation between school start times and sleep in middle school students while accounting for potentially confounding demographic…

Sleep to the beat : A nap favours consolidation of timing

NARCIS (Netherlands)

Verweij, Ilse M; Onuki, Yoshiyuki; Van Someren, Eus J W; Van der Werf, Ysbrand D

Growing evidence suggests that sleep is important for procedural learning, but few studies have investigated the effect of sleep on the temporal aspects of motor skill learning. We assessed the effect of a 90-min day-time nap on learning a motor timing task, using 2 adaptations of a serial

Irregular sleep/wake patterns are associated with poorer academic performance and delayed circadian and sleep/wake timing.

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Phillips, Andrew J K; Clerx, William M; O'Brien, Conor S; Sano, Akane; Barger, Laura K; Picard, Rosalind W; Lockley, Steven W; Klerman, Elizabeth B; Czeisler, Charles A

2017-06-12

The association of irregular sleep schedules with circadian timing and academic performance has not been systematically examined. We studied 61 undergraduates for 30 days using sleep diaries, and quantified sleep regularity using a novel metric, the sleep regularity index (SRI). In the most and least regular quintiles, circadian phase and light exposure were assessed using salivary dim-light melatonin onset (DLMO) and wrist-worn photometry, respectively. DLMO occurred later (00:08 ± 1:54 vs. 21:32 ± 1:48; p sleep propensity rhythm peaked later (06:33 ± 0:19 vs. 04:45 ± 0:11; p academic performance and SRI was observed. These findings show that irregular sleep and light exposure patterns in college students are associated with delayed circadian rhythms and lower academic performance. Moreover, the modeling results reveal that light-based interventions may be therapeutically effective in improving sleep regularity in this population.

Sociodemographic characteristics and waking activities and their role in the timing and duration of sleep.

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Basner, Mathias; Spaeth, Andrea M; Dinges, David F

2014-12-01

Chronic sleep restriction is prevalent in the U.S. population and associated with increased morbidity and mortality. The primary reasons for reduced sleep are unknown. Using population data on time use, we sought to identify individual characteristics and behaviors associated with short sleep that could be targeted for intervention programs. Analysis of the American Time Use Survey (ATUS). Cross-sectional annual survey conducted by the U.S. Bureau of Labor Statistics. Representative cohort (N = 124,517) of Americans 15 years and older surveyed between 2003 and 2011. None. Telephone survey of activities over 24 hours. Relative to all other waking activities, paid work time was the primary waking activity exchanged for sleep. Time spent traveling, which included commuting to/ from work, and immediate pre- and post-sleep activities (socializing, grooming, watching TV) were also reciprocally related to sleep duration. With every hour that work or educational training started later in the morning, sleep time increased by approximately 20 minutes. Working multiple jobs was associated with the highest odds for sleeping ≤6 hours on weekdays (adjusted OR 1.61, 95% CI 1.44; 1.81). Self-employed respondents were less likely to be short sleepers compared to private sector employees (OR 0.83, 95% CI 0.72; 0.95). Sociodemographic characteristics associated with paid work (age 25-64, male sex, high income, and employment per se) were consistently associated with short sleep. U.S. population time use survey findings suggest that interventions to increase sleep time should concentrate on delaying the morning start time of work and educational activities (or making them more flexible), increasing sleep opportunities, and shortening morning and evening commute times. Reducing the need for multiple jobs may increase sleep time, but economic disincentives from working fewer hours will need to be offset. Raising awareness of the importance of sufficient sleep for health and safety may

Sleep timing is more important than sleep length or quality for medical school performance.

Science.gov (United States)

Genzel, L; Ahrberg, K; Roselli, C; Niedermaier, S; Steiger, A; Dresler, M; Roenneberg, T

2013-07-01

Overwhelming evidence supports the importance of sleep for memory consolidation. Medical students are often deprived of sufficient sleep due to large amounts of clinical duties and university load, we therefore investigated how study and sleep habits influence university performance. We performed a questionnaire-based study with 31 medical students of the University of Munich (second and third clinical semesters; surgery and internal medicine). The students kept a diary (in 30-min bins) on their daily schedules (times when they studied by themselves, attended classes, slept, worked on their thesis, or worked to earn money). The project design involved three 2-wk periods (A: during the semester; B: directly before the exam period--pre-exam; C: during the subsequent semester break). Besides the diaries, students completed once questionnaires about their sleep quality (Pittsburgh Sleep Quality Index [PSQI]), their chronotype (Munich Chronotype Questionnaire [MCTQ]), and their academic history (previous grades, including the previously achieved preclinical board exam [PBE]). Analysis revealed significant correlations between the actual sleep behavior during the semester (MS(diary); mid-sleep point averaged from the sleep diaries) during the pre-exam period and the achieved grade (p = 0.002) as well as between the grades of the currently taken exam and the PBE (p = 0.002). A regression analysis with MS(diary) pre-exam and PBE as predictors in a model explained 42.7% of the variance of the exam grade (effect size 0.745). Interestingly, MS(diary)--especially during the pre-exam period-was the strongest predictor for the currently achieved grade, along with the preclinical board exam as a covariate, whereas the chronotype did not significantly influence the exam grade.

Sociodemographic Characteristics and Waking Activities and their Role in the Timing and Duration of Sleep

Science.gov (United States)

Basner, Mathias; Spaeth, Andrea M.; Dinges, David F.

2014-01-01

Study Objectives: Chronic sleep restriction is prevalent in the U.S. population and associated with increased morbidity and mortality. The primary reasons for reduced sleep are unknown. Using population data on time use, we sought to identify individual characteristics and behaviors associated with short sleep that could be targeted for intervention programs. Design: Analysis of the American Time Use Survey (ATUS). Setting: Cross-sectional annual survey conducted by the U.S. Bureau of Labor Statistics. Participants: Representative cohort (N = 124,517) of Americans 15 years and older surveyed between 2003 and 2011. Interventions: None. Measurements and Results: Telephone survey of activities over 24 hours. Relative to all other waking activities, paid work time was the primary waking activity exchanged for sleep. Time spent traveling, which included commuting to/from work, and immediate pre- and post-sleep activities (socializing, grooming, watching TV) were also reciprocally related to sleep duration. With every hour that work or educational training started later in the morning, sleep time increased by approximately 20 minutes. Working multiple jobs was associated with the highest odds for sleeping ≤ 6 hours on weekdays (adjusted OR 1.61, 95% CI 1.44; 1.81). Self-employed respondents were less likely to be short sleepers compared to private sector employees (OR 0.83, 95% CI 0.72; 0.95). Sociodemographic characteristics associated with paid work (age 25-64, male sex, high income, and employment per se) were consistently associated with short sleep. Conclusions: U.S. population time use survey findings suggest that interventions to increase sleep time should concentrate on delaying the morning start time of work and educational activities (or making them more flexible), increasing sleep opportunities, and shortening morning and evening commute times. Reducing the need for multiple jobs may increase sleep time, but economic disincentives from working fewer hours

Interactive vs passive screen time and nighttime sleep duration among school-aged children.

Science.gov (United States)

Yland, Jennifer; Guan, Stanford; Emanuele, Erin; Hale, Lauren

2015-09-01

Insufficient sleep among school-aged children is a growing concern, as numerous studies have shown that chronic short sleep duration increases the risk of poor academic performance and specific adverse health outcomes. We examined the association between weekday nighttime sleep duration and 3 types of screen exposure: television, computer use, and video gaming. We used age 9 data from an ethnically diverse national birth cohort study, the Fragile Families and Child Wellbeing Study, to assess the association between screen time and sleep duration among 9-year-olds, using screen time data reported by both the child (n = 3269) and by the child's primary caregiver (n= 2770). Within the child-reported models, children who watched more than 2 hours of television per day had shorter sleep duration by approximately 11 minutes per night compared to those who watched less than 2 hours of television (β = -0.18; P computer use were associated with reduced sleep duration. For both child- and parent-reported screen time measures, we did not find statistically significant differences in effect size across various types of screen time. Screen time from televisions and computers is associated with reduced sleep duration among 9-year-olds, using 2 sources of estimates of screen time exposure (child and parent reports). No specific type or use of screen time resulted in significantly shorter sleep duration than another, suggesting that caution should be advised against excessive use of all screens.

The Impact of Sleep Timing, Sleep Duration, and Sleep Quality on Depressive Symptoms and Suicidal Ideation amongst Japanese Freshmen: The EQUSITE Study

Directory of Open Access Journals (Sweden)

Atin Supartini

2016-01-01

Full Text Available Aim. The aim of this study was to identify the impact of bedtime, wake time, sleep duration, sleep-onset latency, and sleep quality on depressive symptoms and suicidal ideation amongst Japanese freshmen. Methods. This cross-sectional data was derived from the baseline survey of the Enhancement of Q-University Students Intelligence (EQUSITE study conducted from May to June, 2010. A total of 2,631 participants were recruited and completed the following self-reported questionnaires: the Pittsburgh Sleep Quality Index (PSQI, the Center for Epidemiologic Studies Depression Scale (CES-D, and the original Health Support Questionnaires developed by the EQUSITE study research team. Results. Of 1,992 participants eligible for analysis, 25.5% (n=507 reported depressive symptoms (CES-D total score ≥ 16, and 5.8% (n=115 reported suicidal ideation. The present study showed that late bedtime (later than 01:30, sleep-onset latency (≥30 minutes, and poor sleep quality showed a marginally significant association with depressive symptoms. Poor sleep quality was seen to predict suicidal ideation even after adjusting for depressive symptoms. Conclusion. The current study has important implications for the role of bedtime in the prevention of depressive symptoms. Improving sleep quality may prevent the development of depressive symptoms and reduce the likelihood of suicidal ideation.

School Start Time and Teen Sleep.

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Wahlstrom, Kyla L.

2000-01-01

Sleep studies have shown that teenagers' internal clocks are incompatible with most high schools' early hours. Research in two Minnesota districts indicates that later school starting times can benefit teens and everyone dealing with them. Student participation in sports and other afterschool activities remained high. (MLH)

Later school start time is associated with improved sleep and daytime functioning in adolescents.

Science.gov (United States)

Boergers, Julie; Gable, Christopher J; Owens, Judith A

2014-01-01

Chronic insufficient sleep is a growing concern among adolescents and is associated with a host of adverse health consequences. Early school start times may be an environmental contributor to this problem. The purpose of this study was to examine the impact of a delay in school start time on sleep patterns, sleepiness, mood, and health-related outcomes. Boarding students (n = 197, mean age = 15.6 yr) attending an independent high school completed the School Sleep Habits Survey before and after the school start time was experimentally delayed from 8:00 a.m. to 8:25 a.m. The delay in school start time was associated with a significant (29 min) increase in sleep duration on school nights. The percentage of students receiving 8 or more hours of sleep on a school night increased to more than double, from 18% to 44%. Students in 9th and 10th grade and those with lower baseline sleep amounts were more likely to report improvements in sleep duration after the schedule change. Daytime sleepiness, depressed mood, and caffeine use were all significantly reduced after the delay in school start time. Sleep duration reverted to baseline levels when the original (earlier) school start time was reinstituted. A modest (25 min) delay in school start time was associated with significant improvements in sleep duration, daytime sleepiness, mood, and caffeine use. These findings have important implications for public policy and add to research suggesting the health benefits of modifying school schedules to more closely align with adolescents' circadian rhythms and sleep needs.

Effect of Color Light Stimulation Using LED on Sleep Induction Time

Directory of Open Access Journals (Sweden)

Seonjin Lee

2017-01-01

Full Text Available The effects of color are already being used widely. For this reason, in this study, an attempt was made to use such effects of color to examine the changes in sleep onset through the use of the preferred and nonpreferred color light stimulation. Color light stimulations were randomly presented to the subjects, and based on these colors, the changes in sleep onset were examined through the EEG. Also, to quantify the physiological changes that were caused by each color light stimulation, the changes in the HRV were examined through ECG to determine the level of activation of the autonomous nervous system. The results showed that sleep onset time was changed based on the light stimulation. The result of the EEG analysis showed that sleep onset time was most significantly shortened in preferred color light stimulation. Also, the result of HRV was the fastest change about both the time domain and the frequency domain in the preferred color light stimulation. Therefore, because the preferred color light stimulation activated the parasympathetic nervous system, sleep was induced quickly. Also, by simply using the HRV, the differences in the index of HRV showed changes of sleep onset according to the color light stimulation.

Effects of serotonergic system on the sleeping time and EEG in rats

Directory of Open Access Journals (Sweden)

Alaei H

2001-08-01

Full Text Available The phenomenon of sleep is an active nervous and biologic rhythm, which is under influence of neurotransmitters of central nervous system. In this study, the influence of serotonergic system on sleeping time have been assessed by agonist-antagonist drugs using two methods of induction and non-induction behavioral and electrophysiology. The method used for measurement of total sleeing time was Angle method. For assessment of drugs impact on brain waves, after opening two holes in frontal and temporal regions, two non-polarized silvery electrodes were fixed in above regions and was connected to physiograph and computer by linkers for waves analysis. Injection intra-ventriculary is done by stereotax apparatus. Results indicate that diazepam (2.5 mg/kg increases sleeping time in two stages of induction and non-induction (P<0.01. 5-HTP (15, 45 mg/kg increases dose-dependence sleeping time. p-CPA (150, 300 mg/kg shows biphasic influence on sleeping time. The 300 mg/kg dose of p-CPA reduces sleeping time while 150 mg/kg dose inverts sleeping time (P<0.05. Interferential affects of drugs with (5-HTP 45 mg/kg and p-CPA (300 mg/kg doses are similar to control groups. Injection of 5-HTP inverts p-CPA affect. Intra-ventriculary Injection of 5-HTP in 150 µg/kg and 300 µg/kg doses, decreases frequency of delta waves and significantly increases the frequencies of other waves but conversely, 500 µg/kg decreases it. Due to findings of this study, interferential affects of agonist-antagonist of 5-HTP, can not invert p-CPA affect. Supported by GABA affects, diazepam induces its inhibitory affect in per-synaptic and post-synaptic membrane through ascending reticular both systems and blocking stimulation of brain cortical and limbic system. Affects of two other drugs on sleeping time and brain waves are probably caused by increment of released serotonin in pre-synaptic neurons. Although their interferential affects with other neurotransmitter system should be

Work time control, sleep & accident risk: A prospective cohort study.

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Tucker, Philip; Albrecht, Sophie; Kecklund, Göran; Beckers, Debby G J; Leineweber, Constanze

We examined whether the beneficial impact of work time control (WTC) on sleep leads to lower accident risk, using data from a nationally representative survey conducted in Sweden. Logistic regressions examined WTC in 2010 and 2012 as predictors of accidents occurring in the subsequent 2 years (N = 4840 and 4337, respectively). Sleep disturbance and frequency of short sleeps in 2012 were examined as potential mediators of the associations between WTC in 2010 and subsequent accidents as reported in 2014 (N = 3636). All analyses adjusted for age, sex, education, occupational category, weekly work hours, shift work status, job control and perceived accident risk at work. In both waves, overall WTC was inversely associated with accidents (p = 0.048 and p = 0.038, respectively). Analyses of the sub-dimensions of WTC indicated that Control over Daily Hours (influence over start and finish times, and over length of shift) did not predict accidents in either wave, while Control over Time-off (CoT; influence over taking breaks, running private errands during work and taking paid leave) predicted fewer accidents in both waves (p = 0.013 and p = 0.010). Sleep disturbance in 2012 mediated associations between WTC/CoT in 2010 and accidents in 2014, although effects' sizes were small (effectWTC = -0.006, 95% confidence interval [CI] = -0.018 to -0.001; effectCoT = -0.009, 95%CI = -0.022 to -0.001; unstandardized coefficients), with the indirect effects of sleep disturbance accounting for less than 5% of the total direct and indirect effects. Frequency of short sleeps was not a significant mediator. WTC reduces the risk of subsequently being involved in an accident, although sleep may not be a strong component of the mechanism underlying this association.

Sleep-time sizing and scheduling in green passive optical networks

KAUST Repository

Elrasad, Amr

2012-08-01

Next-generation passive optical network (PON) has been widely considered as a cost-effective broadband access technology. With the ever-increasing power saving concern, energy efficiency has been an important issue for its operations. In this paper, we present a novel sleep time sizing and scheduling framework that satisfies power efficient bandwidth allocation in PONs. We consider the downstream links from an optical line terminal (OLT) to an optical network unit (ONU). The ONU has two classes of traffic, control and data. Control traffic are delay intolerant with higher priority than the data traffic. Closed form model for average ONU sleeping time and end-to-end data traffic delay are presented and evaluated. Our framework decouples the dependency between ONU sleeping time and the QoS of the traffic.

Media Use and Child Sleep: The Impact of Content, Timing, and Environment

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Liekweg, Kimberly; Christakis, Dimitri A.

2011-01-01

BACKGROUND: Media use has been shown to negatively affect a child's sleep, especially in the context of evening use or with a television in the child's bedroom. However, little is known about how content choices and adult co-use affect this relationship. OBJECTIVE: To describe the impact of media content, timing, and use behaviors on child sleep. METHODS: These data were collected in the baseline survey and media diary of a randomized controlled trial on media use in children aged 3 to 5 years. Sleep measures were derived from the Children's Sleep Habits Questionnaire. Media diaries captured time, content title, and co-use of television, video-game, and computer usage; titles were coded for ratings, violence, scariness, and pacing. Nested linear regression models were built to examine the impact of timing, content, and co-use on the sleep problem score. RESULTS: On average, children consumed 72.9 minutes of media screen time daily, with 14.1 minutes occurring after 7:00 pm. Eighteen percent of parents reported at least 1 sleep problem; children with a bedroom television consumed more media and were more likely to have a sleep problem. In regression models, each additional hour of evening media use was associated with a significant increase in the sleep problem score (0.743 [95% confidence interval: 0.373–1.114]), as was daytime use with violent content (0.398 [95% confidence interval: 0.121–0.676]). There was a trend toward greater impact of daytime violent use in the context of a bedroom television (P = .098) and in low-income children (P = .07). CONCLUSIONS: Violent content and evening media use were associated with increased sleep problems. However, no such effects were observed with nonviolent daytime media use. PMID:21708803

Media use and child sleep: the impact of content, timing, and environment.

Science.gov (United States)

Garrison, Michelle M; Liekweg, Kimberly; Christakis, Dimitri A

2011-07-01

Media use has been shown to negatively affect a child's sleep, especially in the context of evening use or with a television in the child's bedroom. However, little is known about how content choices and adult co-use affect this relationship. To describe the impact of media content, timing, and use behaviors on child sleep. These data were collected in the baseline survey and media diary of a randomized controlled trial on media use in children aged 3 to 5 years. Sleep measures were derived from the Children's Sleep Habits Questionnaire. Media diaries captured time, content title, and co-use of television, video-game, and computer usage; titles were coded for ratings, violence, scariness, and pacing. Nested linear regression models were built to examine the impact of timing, content, and co-use on the sleep problem score. On average, children consumed 72.9 minutes of media screen time daily, with 14.1 minutes occurring after 7:00 pm. Eighteen percent of parents reported at least 1 sleep problem; children with a bedroom television consumed more media and were more likely to have a sleep problem. In regression models, each additional hour of evening media use was associated with a significant increase in the sleep problem score (0.743 [95% confidence interval: 0.373-1.114]), as was daytime use with violent content (0.398 [95% confidence interval: 0.121-0.676]). There was a trend toward greater impact of daytime violent use in the context of a bedroom television (P=.098) and in low-income children (P=.07). Violent content and evening media use were associated with increased sleep problems. However, no such effects were observed with nonviolent daytime media use. Copyright © 2011 by the American Academy of Pediatrics.

Expiratory timing in obstructive sleep apnoeas.

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Cibella, F; Marrone, O; Sanci, S; Bellia, V; Bonsignore, G

1990-03-01

Diaphragmatic electromyogram was recorded during NREM sleep in 4 patients affected by obstructive sleep apnoea (OSA) syndrome in order to evaluate the behaviour of expiratory time (TE) in the course of the obstructive apnoea-ventilation cycle. The two components of TE, i.e. time of post-inspiratory inspiratory activity (TPIIA) and time of expiratory phase 2 (TE2) were separately analysed. TPIIA showed a short duration, with only minor variations, within the apnoea, while its duration was more variable and longer in the interapnoeic periods: the longest TPIIA values were associated with the highest inspiratory volumes in the same breaths. This behaviour seemed regulated according to the need of a more or less effective expiratory flow braking, probably as a result of pulmonary stretch receptors discharge. Conversely TE2 showed a continuous gradual modulation, progressively increasing in the pre-apnoeic period, decreasing during the apnoea and increasing in the post-apnoeic period: these TE2 variations seemed related to oscillations in chemical drive. These data show that TE in the obstructive apnoea-ventilation cycle results from a different modulation in its two components and suggest that both mechanical and chemical influences play a role in its overall duration.

Sleep discontinuity and impaired sleep continuity affect transition to and from obesity over time: results from the Alameda county study.

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Nordin, Maria; Kaplan, Robert M

2010-03-01

To investigate the impact of development in sleep continuity on transition to and from obesity over time. The study used self-reported sleep and body mass index (BMI) measures from the 1965, 1974, 1983, and 1994 waves of the longitudinal Alameda County Study. Sleep continuity was assessed by a question on whether the participants had any troubles falling or staying asleep. Change in sleep and BMI were estimated from the sleep and BMI questions in 1965 and 1994 respectively. Multinomial regression analyses were used to examine the risk/chance for a transition to and from obesity (BMI >or=30 kg/m(2)) due to development in sleep continuity. After adjustment for confounding variables, consistent sleep discontinuity both increases the risk for a transition to obesity and reduces the chance of losing weight, whereas impaired sleep continuity lowers the chance for weight loss. Effects for obesity were non-significant for those with improved sleep continuity. Consistent sleep discontinuity and impaired sleep continuity increases the risk of transition to obesity or of remaining obese.

Ion temperature increase during MHD events on the TST-2 spherical tokamak

International Nuclear Information System (INIS)

Ejiri, A.; Shiraiwa, S.; Takase, Y.; Yamada, T.; Nagashima, Y.; Kasahara, H.; Iijima, D.; Kobori, Y.; Nishi, T.; Taniguchi, T.; Aramasu, M.; Ohara, S.; Ushigome, M.; Yamagishi, K.

2003-01-01

Various types of MHD events including internal reconnection events are studied on the TST-2 spherical tokamak. In weak MHD events no positive current spike was observed, but in strong MHD events with positive current spikes, a rapid and significant impurity ion temperature increase was observed. The decrease in the poloidal magnetic energy is the most probable energy source for ion heating. The plasma current shows a stepwise change. The magnitude of this step correlates with the temperature increase and is found to be a good indicator of the strength of each event. (author)

Changes in sleep time and sleep quality across the ovulatory cycle as a function of fertility and partner attractiveness.

Directory of Open Access Journals (Sweden)

Brooke N Gentle

Full Text Available Research suggests that near ovulation women tend to consume fewer calories and engage in more physical activity; they are judged to be more attractive, express greater preferences for masculine and symmetrical men, and experience increases in sexual desire for men other than their primary partners. Some of these cycle phase shifts are moderated by partner attractiveness and interpreted as strategic responses to women's current reproductive context. The present study investigated changes in sleep across the ovulatory cycle, based on the hypothesis that changes in sleep may reflect ancestral strategic shifts of time and energy toward reproductive activities. Participants completed a 32-day daily diary in which they recorded their sleep time and quality for each day, yielding over 1,000 observations of sleep time and quality. Results indicated that, when the probability of conception was high, women partnered with less attractive men slept more, while women with more attractive partners slept less.

Longitudinal Outcomes of Start Time Delay on Sleep, Behavior, and Achievement in High School

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Thacher, Pamela V.; Onyper, Serge V.

2016-01-01

Study Objectives: To establish whether sleep, health, mood, behavior, and academics improved after a 45-minute delay in high school start time, and whether changes persisted longitudinally. Methods: We collected data from school records and student self-report across a number of domains at baseline (May 2012) and at two follow-up time points (November 2012 and May 2013), at a public high school in upstate New York. Students enrolled during academic years (AY) 2011–2012 and 2012–2013 completed the Pittsburgh Sleep Quality Index; the DASS-21; the “Owl-Lark” Scale; the Daytime Sleepiness Index; and a brief self-report of health. Reports from school records regarding attendance, tardiness, disciplinary violations, and academic performance were collected for AY 2010–2011 through 2013–2014. Results: Students delayed but did not extend their sleep period; we found lasting improvements in tardiness and disciplinary violations after the start-time delay, but no changes to other variables. At the first follow-up, students reported 20 minutes longer sleep, driven by later rise times and stable bed times. At the second follow-up, students maintained later rise times but delayed bedtimes, returning total sleep to baseline levels. A delay in rise time, paralleling the delay in the start time that occurred, resulted in less tardiness and decreased disciplinary incidents, but larger improvements to sleep patterns may be necessary to affect health, attendance, sleepiness, and academic performance. Conclusions: Later start times improved tardiness and disciplinary issues at this school district. A delay in start time may be a necessary but not sufficient means to increase sleep time and may depend on preexisting individual differences. Commentary: A commentary on this article appears in this issue on page 267. Citation: Thacher PV, Onyper SV. Longitudinal outcomes of start time delay on sleep, behavior, and achievement in high school. SLEEP 2016;39(2):271–281. PMID

Time to wake up: reactive countermeasures to sleep inertia.

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Hilditch, Cassie J; Dorrian, Jillian; Banks, Siobhan

2016-12-07

Sleep inertia is the period of impaired performance and grogginess experienced after waking. This period of impairment is of concern to workers who are on-call, or nap during work hours, and need to perform safety-critical tasks soon after waking. While several studies have investigated the best sleep timing and length to minimise sleep inertia effects, few have focused on countermeasures -especially those that can be implemented after waking (i.e. reactive countermeasures). This structured review summarises current literature on reactive countermeasures to sleep inertia such as caffeine, light, and temperature and discusses evidence for the effectiveness and operational viability of each approach. Current literature does not provide a convincing evidence-base for a reactive countermeasure. Caffeine is perhaps the best option, although it is most effective when administered prior to sleep and is therefore not strictly reactive. Investigations into light and temperature have found promising results for improving subjective alertness; further research is needed to determine whether these countermeasures can also attenuate performance impairment. Future research in this area would benefit from study design features highlighted in this review. In the meantime, it is recommended that proactive sleep inertia countermeasures are used, and that safety-critical tasks are avoided immediately after waking.

Dim light at night does not disrupt timing or quality of sleep in mice.

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Borniger, Jeremy C; Weil, Zachary M; Zhang, Ning; Nelson, Randy J

2013-10-01

Artificial nighttime illumination has recently become commonplace throughout the world; however, in common with other animals, humans have not evolved in the ecological context of chronic light at night. With prevailing evidence linking the circadian, endocrine, immune, and metabolic systems, understanding these relationships is important to understanding the etiology and progression of several diseases. To eliminate the covariate of sleep disruption in light at night studies, researchers often use nocturnal animals. However, the assumption that light at night does not affect sleep in nocturnal animals remains unspecified. To test the effects of light at night on sleep, we maintained Swiss-Webster mice in standard light/dark (LD) or dim light at night (DLAN) conditions for 8-10 wks and then measured electroencephalogram (EEG) and electromyogram (EMG) biopotentials via wireless telemetry over the course of two consecutive days to determine differences in sleep timing and homeostasis. Results show no statistical differences in total percent time, number of episodes, maximum or average episode durations in wake, slow-wave sleep (SWS), or rapid eye movement (REM) sleep. No differences were evident in SWS delta power, an index of sleep drive, between groups. Mice kept in DLAN conditions showed a relative increase in REM sleep during the first few hours after the dark/light transition. Both groups displayed normal 24-h circadian rhythms as measured by voluntary running wheel activity. Groups did not differ in body mass, but a marked negative correlation of body mass with percent time spent awake and a positive correlation of body mass with time spent in SWS was evident. Elevated body mass was also associated with shorter maximum wake episode durations, indicating heavier animals had more trouble remaining in the wake vigilance state for extended periods of time. Body mass did not correlate with activity levels, nor did activity levels correlate with time spent in

Longitudinal Outcomes of Start Time Delay on Sleep, Behavior, and Achievement in High School.

Science.gov (United States)

Thacher, Pamela V; Onyper, Serge V

2016-02-01

To establish whether sleep, health, mood, behavior, and academics improved after a 45-minute delay in high school start time, and whether changes persisted longitudinally. We collected data from school records and student self-report across a number of domains at baseline (May 2012) and at two follow-up time points (November 2012 and May 2013), at a public high school in upstate New York. Students enrolled during academic years (AY) 2011-2012 and 2012-2013 completed the Pittsburgh Sleep Quality Index; the DASS-21; the "Owl-Lark" Scale; the Daytime Sleepiness Index; and a brief self-report of health. Reports from school records regarding attendance, tardiness, disciplinary violations, and academic performance were collected for AY 2010-2011 through 2013-2014. Students delayed but did not extend their sleep period; we found lasting improvements in tardiness and disciplinary violations after the start-time delay, but no changes to other variables. At the first follow-up, students reported 20 minutes longer sleep, driven by later rise times and stable bed times. At the second follow-up, students maintained later rise times but delayed bedtimes, returning total sleep to baseline levels. A delay in rise time, paralleling the delay in the start time that occurred, resulted in less tardiness and decreased disciplinary incidents, but larger improvements to sleep patterns may be necessary to affect health, attendance, sleepiness, and academic performance. Later start times improved tardiness and disciplinary issues at this school district. A delay in start time may be a necessary but not sufficient means to increase sleep time and may depend on preexisting individual differences. A commentary on this article appears in this issue on page 267. © 2016 Associated Professional Sleep Societies, LLC.

The role of nocturnal oximetry in obstructive sleep apnoea-hypopnoea syndrome screening

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Celestina Ventura

2007-07-01

Full Text Available Aim: The aim of our study was to evaluate the sensitivity and specificity of Nocturnal Oximetry (NO as a diagnostic screening tool for obstructive sleep apnoea hypopnoea syndrome (OSAHS, compared with polysomnography (PSG as the gold standard. Methodology: 63 patients with clinical suspicion of OSAHS and exclusion of respiratory disease underwent PSG and NO. We then determined NO sensitivity, specificity, positive (PPV and negative predictive values (NPV. Results: OSAHS was diagnosed in 47 patients with a mean age of 54 years. In the evaluation of the percentage of Total Sleep Time (TST with oxygen desaturation below 90%, we found significant differences between patients with OSAHS (25.4 ± 29.7% and without OSAHS (1 ± 1.5%, p<0,001. We used two cutoff points to evaluate sensitivity, specificity, positive (PPV and negative predictive values (NPV, based on the severity of O2 desaturation (StO2<90%. Using the first cutoff point we diagnosed with NO as positive all the patients with TST desaturation values ≥1% of the TST. Under these circumstances we found a sensitivity of 76.6%, a specificity of 75%, a PPV of 90% and an NPV value of 52.2% for our screening test (NO. Using the second cutoff point, we diagnosed with NO as positive all the patients with TST desaturation values ≥5% of the TST. With this method we found a sensitivity of 65.9%, a specificity of 100%, a PPV of 100% and an NPV of 50%. Conclusion: NO is a useful screening test for the diagnosis of OSAHS in patients without respiratory disease. Resumo: Objectivo: Foi objectivo deste estudo determinar a sensibilidade e a especificidade da oximetria nocturna (ON como método de screening diagnóstico para a síndroma de apneia-hipopneia obstrutiva do sono (SAHOS, utilizando como método de referência a polissonografia (PSG. Metodologia: Foram incluídos 63 doentes com suspeita clínica de SAHOS e exclusão de doença respiratória, sendo

Sleep Habits and Sleep Problems in Healthy Preschoolers.

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Murthy, C L Srinivasa; Bharti, Bhavneet; Malhi, Prahbhjot; Khadwal, Alka

2015-07-01

To describe the sleep patterns and problems in children aged between 12 and 36 mo of age. This cross sectional survey was collected over a span of 1 y in Advanced Pediatric Centre, PGIMER, Chandigarh and crèches of Chandigarh. Children in the age group of 12 to 36 mo were included in study. Children with chronic illness, developmental delay, seizure disorder and lack of consent were excluded. A total of 368 children were enrolled. Main outcome measures were sleep duration over 1 to 3 y of life; sleep behavior at onset, during and waking of sleep and parent reported sleep problems and their predictors. The average duration of sleep was 12.5 h (S.D = 1.9). The mean total sleep duration and mean day time sleep duration decreased, while mean night time sleep increased as the age advanced from 12 to 36 mo. Following were the frequency of sleep habits seen in the index study; bed time routine was seen only in 68(18.5 %), a regular bed time ritual was seen in 281(76.4 %), 329(89.4 %) children frequently required 0-20 min time to fall asleep, 11(3 %) parents used sleep inducing drugs. Night waking (1 to 3 times a night) was seen in 297(80.7 %) and its frequency declined with age. Parent reported sleep problems were seen in 12.8 % (47/368). Lack of co-sleeping and night waking were considered as strongest predictors of parent reported sleep problems. Toddlers' sleep duration, night waking behavior, and day time naps decrease as the age progress while night time sleep duration increases with age. Lack of co-sleeping and night waking are considered as strongest predictors of parent reported sleep problems.

Direct Measurements of Smartphone Screen-Time: Relationships with Demographics and Sleep

OpenAIRE

Christensen, Matthew A.; Bettencourt, Laura; Kaye, Leanne; Moturu, Sai T.; Nguyen, Kaylin T.; Olgin, Jeffrey E.; Pletcher, Mark J.; Marcus, Gregory M.

2016-01-01

Background Smartphones are increasingly integrated into everyday life, but frequency of use has not yet been objectively measured and compared to demographics, health information, and in particular, sleep quality. Aims The aim of this study was to characterize smartphone use by measuring screen-time directly, determine factors that are associated with increased screen-time, and to test the hypothesis that increased screen-time is associated with poor sleep. Methods We performed a cross-sectio...

Reduction in time-to-sleep through EEG based brain state detection and audio stimulation.

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Zhuo Zhang; Cuntai Guan; Ti Eu Chan; Juanhong Yu; Aung Aung Phyo Wai; Chuanchu Wang; Haihong Zhang

2015-08-01

We developed an EEG- and audio-based sleep sensing and enhancing system, called iSleep (interactive Sleep enhancement apparatus). The system adopts a closed-loop approach which optimizes the audio recording selection based on user's sleep status detected through our online EEG computing algorithm. The iSleep prototype comprises two major parts: 1) a sleeping mask integrated with a single channel EEG electrode and amplifier, a pair of stereo earphones and a microcontroller with wireless circuit for control and data streaming; 2) a mobile app to receive EEG signals for online sleep monitoring and audio playback control. In this study we attempt to validate our hypothesis that appropriate audio stimulation in relation to brain state can induce faster onset of sleep and improve the quality of a nap. We conduct experiments on 28 healthy subjects, each undergoing two nap sessions - one with a quiet background and one with our audio-stimulation. We compare the time-to-sleep in both sessions between two groups of subjects, e.g., fast and slow sleep onset groups. The p-value obtained from Wilcoxon Signed Rank Test is 1.22e-04 for slow onset group, which demonstrates that iSleep can significantly reduce the time-to-sleep for people with difficulty in falling sleep.

School Start Times, Sleep, Behavioral, Health, and Academic Outcomes: a Review of the Literature

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Chapman, Daniel P.; Croft, Janet B.

2015-01-01

BACKGROUND Insufficient sleep in adolescents has been shown to be associated with a wide variety of adverse outcomes, from poor mental and physical health to behavioral problems and lower academic grades. However, most high school students do not get sufficient sleep. Delaying school start times for adolescents has been proposed as a policy change to address insufficient sleep in this population and potentially to improve students’ academic performance, reduce engagement in risk behaviors, and improve health. METHODS This paper reviews 38 reports examining the association between school start times, sleep, and other outcomes among adolescent students. RESULTS Most studies reviewed provide evidence that delaying school start time increases weeknight sleep duration among adolescents, primarily by delaying rise times. Most of the studies saw a significant increase in sleep duration even with relatively small delays in start times of half an hour or so. Later start times also generally correspond to improved attendance, less tardiness, less falling asleep in class, better grades, and fewer motor vehicle crashes. CONCLUSIONS Although additional research is necessary, research results that are already available should be disseminated to stakeholders to enable the development of evidence-based school policies. PMID:27040474

Reciprocal Relations between Children's Sleep and Their Adjustment over Time

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Kelly, Ryan J.; El-Sheikh, Mona

2014-01-01

Child sleep and adjustment research with community samples is on the rise with a recognized need of explicating this association. We examined reciprocal relations between children's sleep and their internalizing and externalizing symptoms using 3 waves of data spanning 5 years. Participants included 176 children at Time 1 (M = 8.68 years; 69%…

Comparison of Commercial Wrist-Based and Smartphone Accelerometers, Actigraphy, and PSG in a Clinical Cohort of Children and Adolescents.

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Toon, Elicia; Davey, Margot J; Hollis, Samantha L; Nixon, Gillian M; Horne, Rosemary S C; Biggs, Sarah N

2016-03-01

To compare two commercial sleep devices, an accelerometer worn as a wristband (UP by Jawbone) and a smartphone application (MotionX 24/7), against polysomnography (PSG) and actigraphy (Actiwatch2) in a clinical pediatric sample. Children and adolescents (n = 78, 65% male, mean age 8.4 ± 4.0 y) with suspected sleep disordered breathing (SDB), simultaneously wore an actiwatch, a commercial wrist-based device and had a smartphone with a sleep application activated placed near their right shoulder, during their diagnostic PSG. Outcome variables were sleep onset latency (SOL), total sleep time (TST), wake after sleep onset (WASO), and sleep efficiency (SE). Paired comparisons were made between PSG, actigraphy, UP, and MotionX 24/7. Epoch-by-epoch comparisons determined sensitivity, specificity, and accuracy between PSG, actigraphy, and UP. Bland-Altman plots determined level of agreement. Differences in bias between SDB severity and developmental age were assessed. No differences in mean TST, WASO, or SE between PSG and actigraphy or PSG and UP were found. Actigraphy overestimated SOL (21 min). MotionX 24/7 underestimated SOL (12 min) and WASO (63 min), and overestimated TST (106 min) and SE (17%). UP showed good sensitivity (0.92) and accuracy (0.86) but poor specificity (0.66) when compared to PSG. Bland-Altman plots showed similar levels of bias in both actigraphy and UP. Bias did not differ by SDB severity, however was affected by age. When compared to PSG, UP was analogous to Actiwatch2 and may have some clinical utility in children with sleep disordered breathing. MotionX 24/7 did not accurately reflect sleep or wake and should be used with caution. © 2016 American Academy of Sleep Medicine.

Increased commuting to school time reduces sleep duration in adolescents.

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Pereira, Erico Felden; Moreno, Claudia; Louzada, Fernando Mazzilli

2014-02-01

Active travel to school has been referred to as one way of increasing the level of daily physical exercise, but the actual impacts on student's general health are not clear. Recently, a possible association between active travel to school and the duration of sleep was suggested. Thus, the aim was of this study to investigate the associations between the type of transportation and travel time to school, the time in bed and sleepiness in the classroom of high school students. Information on sleeping habits and travel to school of 1126 high school students were analyzed, where 55.1% were girls with an average age of 16.24 (1.39) years old, in Santa Maria Municipality, Rio Grande do Sul, Brazil. Multiple linear regression and adjusted prevalence rates analyses were carried out. The frequency of active travel found was 61.8%. Associations between time in bed, sleepiness in the classroom and the type of transportation (active or passive) were not identified. Nevertheless, the time in bed was inversely associated with the travel time (p = 0.036) and with a phase delay. In the adjusted analysis, active travel was more incident for the students of schools in the suburbs (PR: 1.68; CI: 1.40-2.01) in comparison with the students of schools in the center. Therefore, longer trips were associated with a reduction of sleep duration of morning and night groups. Interventions concerning active travel to school must be carried out cautiously in order not to cause a reduction of the sleeping time.

Performance on a simple response time task: Is sleep or work more important for miners?

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Ferguson, Sally A; Paech, Gemma M; Dorrian, Jillian; Roach, Gregory D; Jay, Sarah M

2011-01-01

The purpose of the current study was to investigate the impact of work- and sleep-related factors on an objective measure of response time in a field setting. Thirty-five mining operators working 12-h shift patterns completed daily sleep and work diaries, wore activity monitors continuously and completed palm-based psychomotor vigilance tests (palmPVT) at the start and end of each shift. Linear mixed models were used to test the main effects on response time of roster, timing of test, sleep history and prior wake. The time at which the test occurred was a significant predictor of response time (F₃(,)₄₀₃(.)₄ = 6.72, p times than the start of night shifts, and the start or end of day shifts. Further, the amount of sleep obtained in the 24h prior to the test was also a significant predictor of response time (F₃(,)₄₀₇(.)₀ = 3.05, p time indicative of performance impairments. Of more interest however is that immediate sleep history was also predictive of changes in response time with lower amounts of prior sleep related to slower response times. The current data provides further evidence that sleep is a primary mediator of performance, independent of roster pattern. Copyright © 2010 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Initial results from the TST-2 spherical tokamak

International Nuclear Information System (INIS)

Takase, Y.; Ejiri, A.; Kasuya, N.

2001-01-01

A new spherical tokamak TST-2 was constructed at the University of Tokyo and started operation in September 1999. Reliable plasma initiation is achieved with typically 1 kW of ECH power at 2.45 GHz. Plasma currents of up to 90 kA and toroidal fields of up to 0.2 T have been achieved during the initial experimental campaign. The ion temperature is typically 100 eV. Internal reconnection events (IREs) are often observed. The internal magnetic field measured at r/a=2/3 indicated growth of fluctuations up to the 4 th harmonic, suggesting the existence of modes with several different mode numbers. In the presence of a toroidal field and a vertically oriented mirror field, noninductively driven currents of order 1 kA were observed with 1 kW of ECH power. The driven current increased with decreasing filling pressure, down to 3x10 -6 torr. A study of high harmonic fast wave (HHFW) excitation and propagation has begun. Initial results indicate highly efficient wave launching. (author)

Using Mid-Sleep Time to Determine Chronotype in Young Adults with Insomnia-Related Symptoms

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Sooyeon Suh

2017-12-01

Full Text Available The Munich Chronotype Questionnaire (MCTQ uses sleep behavior to assess chronotype, but the extent to which such sleep behavior based assessments might be useful in populations with sleep disorders, such as insomnia, is currently unclear. We thus systematically assessed sleep disorders, MCTQ and the Morningness-Eveningness Questionnaire (MEQ, another behavioral preferencebased assessment of chronotype, in 310 individuals. In a smaller substudy (n = 121, we compared the MCTQ to sleep diaries in insomnia patients and good sleepers. Insomnia patients had overall lower consistency in chronotypes compared to good sleepers on the MCTQ compared to the MEQ, which was also evident when compared to sleep diaries. As insomnia disorder is characterized by time gaps spent awake during the night due to difficulty maintaining sleep, there may be limitations in using mid-sleep time as an accurate indicator of chronotype in insomnia patients. Our study suggests that the MCTQ should be used in conjunction with another existing questionnaire or assessment tool when assessing chronotype in insomnia patients.

Physical Activity, Study Sitting Time, Leisure Sitting Time, and Sleep Time Are Differently Associated With Obesity in Korean Adolescents: A Population-Based Study.

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Kong, Il Gyu; Lee, Hyo-Jeong; Kim, So Young; Sim, Songyong; Choi, Hyo Geun

2015-11-01

Low physical activity, long leisure sitting time, and short sleep time are risk factors for obesity, but the association with study sitting time is unknown. The objective of this study was to evaluate the association between these factors and obesity.We analyzed the association between physical activity, study sitting time, leisure sitting time, and sleep time and subject weight (underweight, healthy weight, overweight, and obese), using data from a large population-based survey, the 2013 Korea Youth Risk Behavior Web-based Survey. Data from 53,769 participants were analyzed using multinomial logistic regression analyses with complex sampling. Age, sex, region of residence, economic level, smoking, stress level, physical activity, sitting time for study, sitting time for leisure, and sleep time were adjusted as the confounders.Low physical activity (adjusted odds ratios [AORs] = 1.03, 1.12) and long leisure sitting time (AORs = 1.15, 1.32) were positively associated with overweight and obese. Low physical activity (AOR = 1.33) and long leisure sitting time (AOR = 1.12) were also associated with underweight. Study sitting time was negatively associated with underweight (AOR = 0.86) but was unrelated to overweight (AOR = 0.97, 95% confidence interval [CI] = 0.91-1.03) and obese (AOR = 0.94, 95% CI = 0.84-1.04). Sleep time (physical activity, decreasing leisure sitting time, and obtaining sufficient sleep would be beneficial in maintaining a healthy weight. However, study sitting time was not associated with overweight or obese.

Adjustment of sleep and the circadian temperature rhythm after flights across nine time zones

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Gander, Philippa H.; Myhre, Grete; Graeber, R. Curtis; Lauber, John K.; Andersen, Harald T.

1989-01-01

The adjustment of sleep-wake patterns and the circadian temperature rhythm was monitored in nine Royal Norwegian Airforce volunteers operating P-3 aircraft during a westward training deployment across nine time zones. Subjects recorded all sleep and nap times, rated nightly sleep quality, and completed personality inventories. Rectal temperature, heart rate, and wrist activity were continuously monitored. Adjustment was slower after the return eastward flight than after the outbound westward flight. The eastward flight produced slower readjustment of sleep timing to local time and greater interindividual variability in the patterns of adjustment of sleep and temperature. One subject apparently exhibited resynchronization by partition, with the temperature rhythm undergoing the reciprocal 15-h delay. In contrast, average heart rates during sleep were significantly elevated only after westward flight. Interindividual differences in adjustment of the temperature rhythm were correlated with some of the personality measures. Larger phase delays in the overall temperature waveform (as measured on the 5th day after westward flight) were exhibited by extraverts, and less consistently by evening types.

Opposite effects of sleep deprivation on the continuous reaction times in patients with liver cirrhosis and normal persons.

Science.gov (United States)

Lauridsen, Mette Munk; Frøjk, Jesper; de Muckadell, Ove B Schaffalitzky; Vilstrup, Hendrik

2014-09-01

The continuous reaction times (CRT) method describes arousal functions. Reaction time instability in a patient with liver disease indicates covert hepatic encephalopathy (cHE). The effects of sleep deprivation are unknown although cirrhosis patients frequently suffer from sleep disorders. The aim of this study was to determine if sleep deprivation influences the CRT test. Eighteen cirrhosis patients and 27 healthy persons were tested when rested and after one night's sleep deprivation. The patients filled out validated sleep quality questionnaires. Seven patients (38%) had unstable reaction times (a CRTindex sleep that was not related to their CRT tests before or after the sleep deprivation. In the healthy participants, the sleep deprivation slowed their reaction times by 11% (p sleep deprivation normalized or improved the reaction time stability of the patients with a CRTindex below 1.9 and had no effect in the patients with a CRTindex above 1.9. There was no relation between reported sleep quality and reaction time results. Thus, in cirrhosis patients, sleep disturbances do not lead to 'falsely' slowed and unstable reaction times. In contrast, the acute sleep deprivation slowed and destabilized the reaction times of the healthy participants. This may have negative consequences for decision-making.

School Start Times, Sleep, Behavioral, Health, and Academic Outcomes: A Review of the Literature.

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Wheaton, Anne G; Chapman, Daniel P; Croft, Janet B

2016-05-01

Insufficient sleep in adolescents has been shown to be associated with a wide variety of adverse outcomes, from poor mental and physical health to behavioral problems and lower academic grades. However, most high school students do not get sufficient sleep. Delaying school start times for adolescents has been proposed as a policy change to address insufficient sleep in this population and potentially to improve students' academic performance, reduce engagement in risk behaviors, and improve health. This article reviews 38 reports examining the association between school start times, sleep, and other outcomes among adolescent students. Most studies reviewed provide evidence that delaying school start time increases weeknight sleep duration among adolescents, primarily by delaying rise times. Most of the studies saw a significant increase in sleep duration even with relatively small delays in start times of half an hour or so. Later start times also generally correspond to improved attendance, less tardiness, less falling asleep in class, better grades, and fewer motor vehicle crashes. Although additional research is necessary, research results that are already available should be disseminated to stakeholders to enable the development of evidence-based school policies. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Mindfulness-based stress reduction compared with cognitive behavioral therapy for the treatment of insomnia comorbid with cancer: a randomized, partially blinded, noninferiority trial.

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Garland, Sheila N; Carlson, Linda E; Stephens, Alisa J; Antle, Michael C; Samuels, Charles; Campbell, Tavis S

2014-02-10

Our study examined whether mindfulness-based stress reduction (MBSR) is noninferior to cognitive behavioral therapy for insomnia (CBT-I) for the treatment of insomnia in patients with cancer. This was a randomized, partially blinded, noninferiority trial involving patients with cancer with insomnia recruited from a tertiary cancer center in Calgary, Alberta, Canada, from September 2008 to March 2011. Assessments were conducted at baseline, after the program, and after 3 months of follow-up. The noninferiority margin was 4 points measured by the Insomnia Severity Index. Sleep diaries and actigraphy measured sleep onset latency (SOL), wake after sleep onset (WASO), total sleep time (TST), and sleep efficiency. Secondary outcomes included sleep quality, sleep beliefs, mood, and stress. Of 327 patients screened, 111 were randomly assigned (CBT-I, n = 47; MBSR, n = 64). MBSR was inferior to CBT-I for improving insomnia severity immediately after the program (P = .35), but MBSR demonstrated noninferiority at follow-up (P = .02). Sleep diary-measured SOL was reduced by 22 minutes in the CBT-I group and by 14 minutes in the MBSR group at follow-up. Similar reductions in WASO were observed for both groups. TST increased by 0.60 hours for CBT-I and 0.75 hours for MBSR. CBT-I improved sleep quality (P treatment of insomnia.

Time in bed, quality of sleep and school functioning of children.

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Meijer, A M; Habekothé, H T; Van Den Wittenboer, G L

2000-06-01

This study describes the relationship of time in bed and quality of sleep with concentration and functioning at school. Neurotic and psychosomatic symptoms have been used as control variables. The sample consisted of 449 Dutch children in the seventh and eighth grades of elementary school. The age of the children varied between 9 y 5 mo and 14 y 5 mo. Seven schools participated in the research, with a total of 18 classes. The results indicated that 43% of the children had difficulty getting up in the morning. Furthermore, 15% of the children reported sleep problems and 25% did not feel rested at school. Time in bed and sleep quality show no relationship with concentration. Sleep quality, feeling rested at school and less distinct bedtimes were clearly related to school functioning. Another result was that children who had no difficulty getting up displayed more achievement motivation. Being open to the teacher's influence and achievement motivation depended mainly on sleep characteristics. Not getting bored at school, self-image as a pupil and control over aggressive behaviour were also influenced by gender, age, neuroticism and neurosomaticism.

Cocaine potentiates ketamine-induced loss of the righting reflex and sleeping time in mice. Role of catecholamines.

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Vanderwende, C; Spoerlein, M T; Lapollo, J

1982-07-01

Cocaine in graded doses potentiated ketamine-induced loss of the righting reflex and sleeping time. Potentiation of drug-induced sleep with cocaine was not a generalized phenomenon inasmuch as it had no effect on sleep induced by pentobarbital or hexobarbital and decreased sleep induced by phenobarbital. Pentylenetetrazole reduced ketamine sleep but d-amphetamine had a potentiative action. dl-alpha-Methyl-p-tyrosine methyl ester itself increased both the number losing the righting reflex and the sleeping time induced by ketamine. However, the effect cocaine on sleeping time was blocked 3 h after the dl-alpha-methyl-p-tyrosine methyl ester was given. The alpha and beta adrenergic blocking drugs, phenoxybenzamine and propranolol, increased the number of animals losing the righting reflex with ketamine, and phenoxybenzamine lengthened the sleeping time. Alpha and beta adrenergic agonists, l-phenylephrine and isoproterenol, increased the number of animals going to sleep with ketamine but did not significantly alter how long they would sleep. The agonists had no effect on the cocaine interaction with ketamine, whereas the antagonists blocked the effect of cocaine. Both stimulation and blockade of dopamine receptors led to increased loss of the righting reflex and sleeping time with ketamine but only receptor blockade antagonized the effect of cocaine on ketamine-induced sleep. Thus, both the noradrenergic and dopaminergic systems appear to be involved in the ability of cocaine to potentiate ketamine-induced sleep.

Sleeping position and reported night-time asthma symptoms and medication.

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Kalolella, Admirabilis Beno

2016-01-01

A 49 years old man, known case of bronchial asthma for 43 years, with history of frequent asthmatic attacks, usually responding to double dose of intravenous Aminophylline and double dose of Hydrocortisone was received at medical emergency care unit at midnight with night-time asthma attack. The attack did not settle with Aminophylline single Intravenous injection. He was then admitted and put in supine sleep position for re-evaluation while his asthma symptoms were monitored while waiting for the medical officer's evaluation of his asthma status. After 3 hours of observation, asthma symptoms were relieved, and patient was discharged home and advised to sleep in supine position throughout every night to prevent asthma symptoms. The patient was followed up through nighttime sleep diary for one month. After one month period of monitoring, the patient had significance reduction in asthma symptoms and reduced night time medication, reduced episodes of night awakening due to asthma symptoms, and improved capability for normal works. This case report describes a novel approach of management and prophylaxis of asthmatic episodes through sleeping position that reduces and control asthma symptoms resulting in reduced drug consumption.

Kinetics of the QuantiFERON-TB Gold In-Tube test during treatment of patients with sputum smear-positive tuberculosis in relation to initial TST result and severity of disease

DEFF Research Database (Denmark)

Idh, Jonna; Abate, Ebba; Westman, Anna

2010-01-01

. Smear-positive TB patients (n = 71) were recruited at Gondar University Hospital, Ethiopia. The TST, QFN, CD4+ cell count and clinical symptoms (TB score) were assessed and followed up during treatment. From baseline to 7 months after treatment, there was a significant decrease in QFN reactivity (93.......8% to 62.5% in HIV-negative/TB; 70.3% to 33.3% in HIV-positive/TB patients) down to a level comparable to a control group of blood donors (51.2%). The agreement between TST and QFN was poor in TB patients compared to healthy controls. A negative TST correlated to more advanced TB in contrast to a negative...

The Sleep-Time Cost of Parenting: Sleep Duration and Sleepiness Among Employed Parents in the Wisconsin Sleep Cohort Study

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Hagen, Erika W.; Mirer, Anna G.; Palta, Mari; Peppard, Paul E.

2013-01-01

Insufficient sleep is associated with poor health and increased mortality. Studies on whether parenthood (including consideration of number and ages of children) is associated with sleep duration or sleep problems are scant and inconclusive. Using data collected in the Wisconsin Sleep Cohort Study (n = 4,809) between 1989 and 2008, we examined cross-sectional associations of number and ages of children with self-reported parental sleep duration, daytime sleepiness, and dozing among employed adults. Longitudinal change in sleep duration over 19 years was examined to evaluate changes in parental sleep associated with children transitioning into adulthood (n = 833). Each child under age 2 years was associated with 13 fewer minutes of parental sleep per day (95% confidence interval (CI): 5, 21); each child aged 2–5 years was associated with 9 fewer minutes of sleep (95% CI: 5, 13); and each child aged 6–18 years was associated with 4 fewer minutes (95% CI: 2, 6). Adult children were not associated with shorter parental sleep duration. Parents of children over age 2 years were significantly more likely to experience daytime sleepiness and dozing during daytime activities. Parents of minor children at baseline had significantly greater increases in sleep duration over 19 years of follow-up. Parenting minor children is associated with shorter sleep duration. As children age into adulthood, the sleep duration of parents with more children approaches that of parents with fewer children. PMID:23378502

Delayed sleep timing and symptoms in adults with attention-deficit/hyperactivity disorder: a controlled actigraphy study.

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Gamble, Karen L; May, Roberta S; Besing, Rachel C; Tankersly, Amelia P; Fargason, Rachel E

2013-05-01

Patients with attention-deficit/hyperactivity disorder (ADHD) often exhibit disrupted sleep and circadian rhythms. Determination of whether sleep disturbance and/or circadian disruption are differentially associated with symptom severity is necessary to guide development of future treatment strategies. Therefore, we measured sleep and ADHD symptoms in participants aged 19-65 who met the DSM-IV-TR (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision) criteria for ADHD and insomnia without psychiatric comorbidities by monitoring actigraphy and daily sleep logs for 2 wks, as well as the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), the ADHD Rating Scale (ADHD-RS), and a clinic-designed sleep behavior questionnaire. Principal components analysis identified correlated circadian- and sleep-related variables in all participants with ADHD who completed the study (n = 24). The identified components were entered into a backwards stepwise linear regression analysis, which indicated that delayed sleep timing and increased sleepiness (ESS) (but not sleep duration or sleep efficiency) significantly predicted greater severity of both hyperactive-impulsive and inattentive ADHD symptoms (p sleep quality (PSQI scores; p sleep" compared with 57.2% and 50% of inattentive and symptom-controlled participants, respectively (p sleep timing and daytime sleepiness, suggesting that treatment interventions aimed at advancing circadian phase may improve daytime sleepiness. In addition, ADHD adults with combined hyperactive-impulsive and inattentive symptoms have decreased sleep quality as well as the delayed sleep timing of predominately inattentive subtypes.

Delayed school start times and adolescent sleep: A systematic review of the experimental evidence.

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Minges, Karl E; Redeker, Nancy S

2016-08-01

Many schools have instituted later morning start times to improve sleep, academic, and other outcomes in response to the mismatch between youth circadian rhythms and early morning start times. However, there has been no systematic synthesis of the evidence on the effects of this practice. To examine the impact of delayed school start time on students' sleep, health, and academic outcomes, electronic databases were systematically searched and data were extracted using the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Six studies satisfied selection criteria and used pre-post, no control (n = 3), randomized controlled trial (n = 2), and quasi-experimental (n = 1) designs. School start times were delayed 25-60 min, and correspondingly, total sleep time increased from 25 to 77 min per weeknight. Some studies revealed reduced daytime sleepiness, depression, caffeine use, tardiness to class, and trouble staying awake. Overall, the evidence supports recent non-experimental study findings and calls for policy that advocates for delayed school start time to improve sleep. This presents a potential long-term solution to chronic sleep restriction during adolescence. However, there is a need for rigorous randomized study designs and reporting of consistent outcomes, including objective sleep measures and consistent measures of health and academic performance. Copyright © 2015 Elsevier Ltd. All rights reserved.

A longitudinal assessment of sleep timing, circadian phase, and phase angle of entrainment across human adolescence.

Directory of Open Access Journals (Sweden)

Stephanie J Crowley

Full Text Available The aim of this descriptive analysis was to examine sleep timing, circadian phase, and phase angle of entrainment across adolescence in a longitudinal study design. Ninety-four adolescents participated; 38 (21 boys were 9-10 years ("younger cohort" and 56 (30 boys were 15-16 years ("older cohort" at the baseline assessment. Participants completed a baseline and then follow-up assessments approximately every six months for 2.5 years. At each assessment, participants wore a wrist actigraph for at least one week at home to measure self-selected sleep timing before salivary dim light melatonin onset (DLMO phase - a marker of the circadian timing system - was measured in the laboratory. Weekday and weekend sleep onset and offset and weekend-weekday differences were derived from actigraphy. Phase angles were the time durations from DLMO to weekday sleep onset and offset times. Each cohort showed later sleep onset (weekend and weekday, later weekend sleep offset, and later DLMO with age. Weekday sleep offset shifted earlier with age in the younger cohort and later in the older cohort after age 17. Weekend-weekday sleep offset differences increased with age in the younger cohort and decreased in the older cohort after age 17. DLMO to sleep offset phase angle narrowed with age in the younger cohort and became broader in the older cohort. The older cohort had a wider sleep onset phase angle compared to the younger cohort; however, an age-related phase angle increase was seen in the younger cohort only. Individual differences were seen in these developmental trajectories. This descriptive study indicated that circadian phase and self-selected sleep delayed across adolescence, though school-day sleep offset advanced until no longer in high school, whereupon offset was later. Phase angle changes are described as an interaction of developmental changes in sleep regulation interacting with psychosocial factors (e.g., bedtime autonomy.

Total sleep time, alcohol consumption, and the duration and severity of alcohol hangover

NARCIS (Netherlands)

van Schrojenstein Lantman, Marith; Mackus, Marlou; Roth, Thomas; Verster, Joris C|info:eu-repo/dai/nl/241442702

2017-01-01

INTRODUCTION: An evening of alcohol consumption often occurs at the expense of sleep time. The aim of this study was to determine the relationship between total sleep time and the duration and severity of the alcohol hangover. METHODS: A survey was conducted among Dutch University students to

The relationship between complaints of night-time heartburn and sleep-related gastroesophageal reflux.

Science.gov (United States)

Orr, W C; Goodrich, S; Estep, M E; Shepherd, K

2014-01-01

This study investigated whether the complaint of night-time heartburn (NHB) as opposed to daytime heartburn (DHB) is a reliable reflection of actual sleep-related reflux events. Three groups of individuals were studied: individuals with complaints of NHB at least twice per week (n = 24), individuals with complaints of DHB (n = 23), and normal participants without any complaints of regular heartburn during the day or night (n = 25). All three groups were studied on one occasion with combined pH monitoring and polysomnography, and subjective questionnaires about sleep disturbance and sleep quality were given to all participants. The NHB group had significantly more sleep-related reflux events compared with both DHB and control groups (P < 0.01). DHB subjects had significantly (P < 0.05) more sleep-related reflux events than normal controls. Total acid contact time (ACT) was significantly (P < 0.05) elevated in the NHB group compared with both the DHB and control group. Sleep-related ACT was also significantly (P < 0.05) elevated in the NHB group compared with the other two groups, while upright (daytime) ACT was not significantly different. The NHB group was significantly (P < 0.05) worse regarding measures of both objective and subjective sleep quality. Subjects with exclusively DHB do have sleep-related reflux that is greater than normal controls. Subjects with NHB have significantly more sleep-related reflux, and both objective and subjective sleep abnormalities compared with normal controls. Complaints of NHB reflect sleep-related reflux events and may be indicative of a more clinically significant condition. © 2013 Wiley Periodicals, Inc. and the International Society for Diseases of the Esophagus.

REM sleep complicates period adding bifurcations from monophasic to polyphasic sleep behavior in a sleep-wake regulatory network model for human sleep

OpenAIRE

Kalmbach, K.; Booth, V.; Behn, C. G. Diniz

2017-01-01

The structure of human sleep changes across development as it consolidates from the polyphasic sleep of infants to the single nighttime sleep period typical in adults. Across this same developmental period, time scales of the homeostatic sleep drive, the physiological drive to sleep that increases with time spent awake, also change and presumably govern the transition from polyphasic to monophasic sleep behavior. Using a physiologically-based, sleep-wake regulatory network model for human sle...

Sleep deprivation and time-on-task performance decrement in the rat psychomotor vigilance task.

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Oonk, Marcella; Davis, Christopher J; Krueger, James M; Wisor, Jonathan P; Van Dongen, Hans P A

2015-03-01

The rat psychomotor vigilance task (rPVT) was developed as a rodent analog of the human psychomotor vigilance task (hPVT). We examined whether rPVT performance displays time-on-task effects similar to those observed on the hPVT. The rPVT requires rats to respond to a randomly presented light stimulus to obtain a water reward. Rats were water deprived for 22 h prior to each 30-min rPVT session to motivate performance. We analyzed rPVT performance over time on task and as a function of the response-stimulus interval, at baseline and after sleep deprivation. The study was conducted in an academic research vivarium. Male Long-Evans rats were trained to respond to a 0.5 sec stimulus light within 3 sec of stimulus onset. Complete data were available for n = 20 rats. Rats performed the rPVT for 30 min at baseline and after 24 h total sleep deprivation by gentle handling. Compared to baseline, sleep deprived rats displayed increased performance lapses and premature responses, similar to hPVT lapses of attention and false starts. However, in contrast to hPVT performance, the time-on-task performance decrement was not significantly enhanced by sleep deprivation. Moreover, following sleep deprivation, rPVT response times were not consistently increased after short response-stimulus intervals. The rPVT manifests similarities to the hPVT in global performance outcomes, but not in post-sleep deprivation effects of time on task and response-stimulus interval. © 2015 Associated Professional Sleep Societies, LLC.

Effects of different sleep deprivation protocols on sleep perception in healthy volunteers.

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Goulart, Leonardo I; Pinto, Luciano R; Perlis, Michael L; Martins, Raquel; Caboclo, Luis Otavio; Tufik, Sergio; Andersen, Monica L

2014-10-01

To investigate whether different protocols of sleep deprivation modify sleep perception. The effects of total sleep deprivation (TD) and selective rapid eye movement (REM) sleep deprivation (RD) on sleep perception were analyzed in normal volunteers. Thirty-one healthy males with normal sleep were randomized to one of three conditions: (i) normal uninterrupted sleep; (ii) four nights of RD; or (iii) two nights of TD. Morning perception of total sleep time was evaluated for each condition. Sleep perception was estimated using total sleep time (in hours) as perceived by the volunteer divided by the total sleep time (in hours) measured by polysomnography (PSG). The final value of this calculation was defined as the perception index (PI). There were no significant differences among the three groups of volunteers in the total sleep time measured by PSG or in the perception of total sleep time at baseline condition. Volunteers submitted to RD exhibited lower sleep PI scores as compared with controls during the sleep deprivation period (P sleep deprivation reduced the ability of healthy young volunteers to perceive their total sleep time when compared with time measured by PSG. The data reinforce the influence of sleep deprivation on sleep perception. Copyright © 2014 Elsevier B.V. All rights reserved.

Adolescents' sleep in low-stress and high-stress (exam) times: a prospective quasi-experiment

NARCIS (Netherlands)

Dewald, J.F.; Meijer, A.M.; Oort, F.J.; Kerkhof, G.A.; Bögels, S.M.

2014-01-01

This prospective quasi-experiment (N=175; mean age: 15.14 years) investigates changes in adolescents' sleep from low-stress (regular school week) to high-stress times (exam week) and examines the (moderating) role of chronic sleep reduction, baseline stress, and gender. Sleep was monitored over

Adolescents' Sleep in Low-Stress and High-Stress (Exam) Times: A Prospective Quasi-Experiment

NARCIS (Netherlands)

Dewald, Julia F.; Meijer, Anne Marie; Oort, Frans J.; Kerkhof, Gerard A.; Bögels, Susan M.

2014-01-01

This prospective quasi-experiment (N = 175; mean age = 15.14 years) investigates changes in adolescents' sleep from low-stress (regular school week) to high-stress times (exam week), and examines the (moderating) role of chronic sleep reduction, baseline stress, and gender. Sleep was monitored over

Effect of Olanzapine on Clinical and Polysomnography Profiles in Patients with Schizophrenia

Directory of Open Access Journals (Sweden)

Mohammad Zia Ul Haq Katshu

2018-01-01

Full Text Available Acute and short-term administration of olanzapine has a favorable effect on sleep in schizophrenia patients. This study aimed to clarify the effect of olanzapine on polysomnographic profiles of schizophrenia patients during the acute phase of illness after controlling for previous drug exposure. Twenty-five drug-naïve or drug-free schizophrenia patients were assessed at baseline and after six weeks of olanzapine treatment on Brief Psychiatric Rating Scale (BPRS, Positive and Negative Syndrome Scale (PANSS, and Udvalg for Kliniske Undersogelser (UKU side-effect rating scale and a whole-night polysomnography; fifteen patients completed the study. There was a significant reduction in all psychopathological variables with maximum reduction in PANSS total, BPRS total, and PANSS positive scores. A significant increase in total sleep time (TST, sleep efficiency (SE, nonrapid eye movement (NREM stage 1 duration, stage 3 duration, stage 4 duration, and stage 4 percentage of TST, number of rapid eye movement (REM periods, REM duration, and REM percentage of TST was observed. REM latency at baseline inversely predicted the reduction in BPRS total and PANSS total and positive scores. In summary, short-term treatment with olanzapine produced significant improvement in clinical and polysomnography profiles of patients with schizophrenia with shorter REM latency predicting a good clinical response.

Behavioural sleep treatments and night time crying in infants: challenging the status quo.

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Blunden, Sarah L; Thompson, Kirrilly R; Dawson, Drew

2011-10-01

In Australia, as in many Westernised industrialised nations, the majority of families encourage infants to sleep alone or 'solo' from an early age. Sleeping solo can increase night time crying, which in turn disrupts sleep for both parent and infant. Night time waking and crying are frequently culturally constructed as behavioural sleep 'problems'. The pursuit of solo sleeping is thus achieved through 'behavioural sleep treatments' that teach an infant to sleep alone. Some behavioural extinction treatments necessitate a parent leaving an infant to cry for extended periods unattended, a practice reportedly difficult for parents. Despite parent's anxieties, and the potential (though little studied) stress to the infant, the pursuit of those behavioural sleep treatments are advocated by many psychologists and clinicians as acceptable and necessary interventions. This paper questions this necessity and critically reviews and debates these methods from biological, anthropological and cultural perspectives. Specifically, it considers Foucaultian, Leidloffian, attachment and behavioural perspectives. The central debate in this paper is if and why an infant's nocturnal cries should be ignored. It challenges the aetiology and acceptance of the status quo in the hope of revisiting the underlying belief that these methods are necessary. In doing so, the paper theorises the ways in which current sleep training techniques do or do not satisfy the needs of infants and their parents and questions the extent to which they can be reconciled. The paper posits an agenda for further research in the area that may facilitate the reconciliation of the needs of parents and those of their infants. Copyright © 2010 Elsevier Ltd. All rights reserved.

The Time Course of the Probability of Transition Into and Out of REM Sleep

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Bassi, Alejandro; Vivaldi, Ennio A.; Ocampo-Garcés, Adrián

2009-01-01

Study Objectives: A model of rapid eye movement (REM) sleep expression is proposed that assumes underlying regulatory mechanisms operating as inhomogenous Poisson processes, the overt results of which are the transitions into and out of REM sleep. Design: Based on spontaneously occurring REM sleep episodes (“Episode”) and intervals without REM sleep (“Interval”), 3 variables are defined and evaluated over discrete 15-second epochs using a nonlinear logistic regression method: “Propensity” is the instantaneous rate of into-REM transition occurrence throughout an Interval, “Volatility” is the instantaneous rate of out-of-REM transition occurrence throughout an Episode, and “Opportunity” is the probability of being in non-REM (NREM) sleep at a given time throughout an Interval, a requisite for transition. Setting: 12:12 light:dark cycle, isolated boxes. Participants: Sixteen male Sprague-Dawley rats Interventions: None. Spontaneous sleep cycles. Measurements and Results: The highest levels of volatility and propensity occur, respectively, at the very beginning of Episodes and Intervals. The new condition stabilizes rapidly, and variables reach nadirs at minute 1.25 and 2.50, respectively. Afterward, volatility increases markedly, reaching values close to the initial level. Propensity increases moderately, the increment being stronger through NREM sleep bouts occurring at the end of long Intervals. Short-term homeostasis is evidenced by longer REM sleep episodes lowering propensity in the following Interval. Conclusions: The stabilization after transitions into Episodes or Intervals and the destabilization after remaining for some time in either condition may be described as resulting from continuous processes building up during Episodes and Intervals. These processes underlie the overt occurrence of transitions. Citation: Bassi A; Vivaldi EA; Ocampo-Garcées A. The time course of the probability of transition into and out of REM sleep. SLEEP 2009

Quantitative analysis of sleep EEG microstructure in the time-frequency domain.

Science.gov (United States)

De Carli, Fabrizio; Nobili, Lino; Beelke, Manolo; Watanabe, Tsuyoshi; Smerieri, Arianna; Parrino, Liborio; Terzano, Mario Giovanni; Ferrillo, Franco

2004-06-30

A number of phasic events influence sleep quality and sleep macrostructure. The detection of arousals and the analysis of cyclic alternating patterns (CAP) support the evaluation of sleep fragmentation and instability. Sixteen polygraphic overnight recordings were visually inspected for conventional Rechtscaffen and Kales scoring, while arousals were detected following the criteria of the American Sleep Disorders Association (ASDA). Three electroencephalograph (EEG) segments were associated to each event, corresponding to background activity, pre-arousal period and arousal. The study was supplemented by the analysis of time-frequency distribution of EEG within each subtype of phase A in the CAP. The arousals were characterized by the increase of alpha and beta power with regard to background. Within NREM sleep most of the arousals were preceded by a transient increase of delta power. The time-frequency evolution of the phase A of the CAP sequence showed a strong prevalence of delta activity during the whole A1, but high amplitude delta waves were found also in the first 2/3 s of A2 and A3, followed by desynchronization. Our results underline the strict relationship between the ASDA arousals, and the subtype A2 and A3 within the CAP: in both the association between a short sequence of transient slow waves and the successive increase of frequency and decrease of amplitude characterizes the arousal response.

The Timing of the Circadian Clock and Sleep Differ between Napping and Non-Napping Toddlers.

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Akacem, Lameese D; Simpkin, Charles T; Carskadon, Mary A; Wright, Kenneth P; Jenni, Oskar G; Achermann, Peter; LeBourgeois, Monique K

2015-01-01

The timing of the internal circadian clock shows large inter-individual variability across the lifespan. Although the sleep-wakefulness pattern of most toddlers includes an afternoon nap, the association between napping and circadian phase in early childhood remains unexplored. This study examined differences in circadian phase and sleep between napping and non-napping toddlers. Data were collected on 20 toddlers (34.2±2.0 months; 12 females; 15 nappers). Children followed their habitual napping and non-napping sleep schedules (monitored with actigraphy) for 5 days before an in-home salivary dim light melatonin onset (DLMO) assessment. On average, napping children fell asleep during their nap opportunities on 3.6±1.2 of the 5 days before the DLMO assessment. For these napping children, melatonin onset time was 38 min later (p = 0.044; d = 0.93), actigraphically-estimated bedtime was 43 min later (p = 0.014; d = 1.24), sleep onset time was 59 min later (p = 0.006; d = 1.46), and sleep onset latency was 16 min longer (p = 0.030; d = 1.03) than those not napping. Midsleep and wake time did not differ by napping status. No difference was observed in the bedtime, sleep onset, or midsleep phase relationships with DLMO; however, the wake time phase difference was 47 min smaller for napping toddlers (p = 0.029; d = 1.23). On average, nappers had 69 min shorter nighttime sleep durations (p = 0.006; d = 1.47) and spent 49 min less time in bed (p = 0.019; d = 1.16) than non-nappers. Number of days napping was correlated with melatonin onset time (r = 0.49; p = 0.014). Our findings indicate that napping influences individual variability in melatonin onset time in early childhood. The delayed bedtimes of napping toddlers likely permits light exposure later in the evening, thereby delaying the timing of the clock and sleep. Whether the early developmental trajectory of circadian phase involves an advance associated with the decline in napping is a question necessitating

The Timing of the Circadian Clock and Sleep Differ between Napping and Non-Napping Toddlers.

Directory of Open Access Journals (Sweden)

Lameese D Akacem

Full Text Available The timing of the internal circadian clock shows large inter-individual variability across the lifespan. Although the sleep-wakefulness pattern of most toddlers includes an afternoon nap, the association between napping and circadian phase in early childhood remains unexplored. This study examined differences in circadian phase and sleep between napping and non-napping toddlers. Data were collected on 20 toddlers (34.2±2.0 months; 12 females; 15 nappers. Children followed their habitual napping and non-napping sleep schedules (monitored with actigraphy for 5 days before an in-home salivary dim light melatonin onset (DLMO assessment. On average, napping children fell asleep during their nap opportunities on 3.6±1.2 of the 5 days before the DLMO assessment. For these napping children, melatonin onset time was 38 min later (p = 0.044; d = 0.93, actigraphically-estimated bedtime was 43 min later (p = 0.014; d = 1.24, sleep onset time was 59 min later (p = 0.006; d = 1.46, and sleep onset latency was 16 min longer (p = 0.030; d = 1.03 than those not napping. Midsleep and wake time did not differ by napping status. No difference was observed in the bedtime, sleep onset, or midsleep phase relationships with DLMO; however, the wake time phase difference was 47 min smaller for napping toddlers (p = 0.029; d = 1.23. On average, nappers had 69 min shorter nighttime sleep durations (p = 0.006; d = 1.47 and spent 49 min less time in bed (p = 0.019; d = 1.16 than non-nappers. Number of days napping was correlated with melatonin onset time (r = 0.49; p = 0.014. Our findings indicate that napping influences individual variability in melatonin onset time in early childhood. The delayed bedtimes of napping toddlers likely permits light exposure later in the evening, thereby delaying the timing of the clock and sleep. Whether the early developmental trajectory of circadian phase involves an advance associated with the decline in napping is a question

Workplace bullying, sleep problems and leisure-time physical activity: a prospective cohort study

DEFF Research Database (Denmark)

Hansen, Åse Marie; Gullander, Maria; Hogh, Annie

2015-01-01

and Harassment (WBH) cohort (N=3278) or the Psychosocial Risk Factors for Stress and Mental Disease (PRISME) cohort (N=4455). We measured workplace bullying using one question that was preceded by a definition of bullying. We used the Karolinska sleep questionnaire to assess sleep problems. The number of hours......OBJECTIVES: Workplace bullying is a potent stressor that may increase sleep problems. Since physical fitness improves resilience to stress, it seems plausible that recreational physical activities may moderate the association between bullying and sleep. The study aimed to examine prospectively...... whether (i) bullying increases the risk of sleep problems, and (ii) the association between bullying and sleep problems is moderated by leisure-time physical activity (LTPA). METHODS: The study sample comprised a cohort of public and private sector employees, who were enrolled into the Work Bullying...

Associations between physical activity, sedentary time, sleep duration and daytime sleepiness in US adults.

Science.gov (United States)

McClain, James J; Lewin, Daniel S; Laposky, Aaron D; Kahle, Lisa; Berrigan, David

2014-09-01

To examine the associations between objectively measured physical activity (PA) or sedentary behavior and self-reported sleep duration or daytime sleepiness in a nationally representative sample of healthy US adults (N=2128). We report analyses of four aspects of sedentary behavior and PA derived from accelerometry data (minutes of sedentary time, activity counts/minute, Minutes of Moderate and Vigorous PA [MVPA], and MVPA in 10-minute bouts) versus self-report of sleep duration and frequency of daytime sleepiness from the 2005-2006 National Health and Nutrition Examination Survey. Age and sex dependence of associations between PA and sleep were observed. Aspects of PA were significantly lower in adults reporting more frequent daytime sleepiness in younger (20-39) and older (≥ 60) age groups, but not in middle-aged (40-59), respondents. In younger respondents, PA increased with sleep duration, but in middle aged and older respondents PA was either unrelated to sleep duration or lower in those reporting ≥ 8 h of sleep. Objectively measured sedentary time showed limited evidence of associations with sleep duration. Further research delineating the relationships between sleep and PA is important because both activities have been implicated in diverse health outcomes as well as in the etiology of obesity. Published by Elsevier Inc.

Opposite effects of sleep deprivation on the continuous reaction times in patients with liver cirrhosis and normal persons

DEFF Research Database (Denmark)

Lauridsen, Mette Munk; Frøjk, Jesper; de Muckadell, Ove B Schaffalitzky

2014-01-01

of this study was to determine if sleep deprivation influences the CRT test. Eighteen cirrhosis patients and 27 healthy persons were tested when rested and after one night's sleep deprivation. The patients filled out validated sleep quality questionnaires. Seven patients (38 %) had unstable reaction times (a...... CRTindex change in the other patients' reaction speed or stability. Seven patients (38 %) reported poor sleep that was not related to their CRT tests before...... or after the sleep deprivation. In the healthy participants, the sleep deprivation slowed their reaction times by 11 % (p persons (25 %) destabilized them. The acute sleep deprivation normalized or improved the reaction time stability of the patients with a CRTindex below 1.9 and had...

A Fully Polynomial-Time Approximation Scheme for Speed Scaling with Sleep State

OpenAIRE

Antoniadis, Antonios; Huang, Chien-Chung; Ott, Sebastian

2014-01-01

We study classical deadline-based preemptive scheduling of tasks in a computing environment equipped with both dynamic speed scaling and sleep state capabilities: Each task is specified by a release time, a deadline and a processing volume, and has to be scheduled on a single, speed-scalable processor that is supplied with a sleep state. In the sleep state, the processor consumes no energy, but a constant wake-up cost is required to transition back to the active state. In contrast to speed sc...

Effects of exercise timing on sleep architecture and nocturnal blood pressure in prehypertensives

Directory of Open Access Journals (Sweden)

Fairbrother K

2014-12-01

Full Text Available Kimberly Fairbrother,1 Ben Cartner,1 Jessica R Alley,1 Chelsea D Curry,1, David L Dickinson,2 David M Morris,1 Scott R Collier1 1Vascular Biology and Autonomic Studies Laboratory, Department of Health and Exercise Science, 2Department of Economics, Appalachian State University, Boone, NC, USA Background: During nocturnal sleep, blood pressure (BP “dips” compared to diurnal BP, reducing stress on the cardiovascular system. Both the hypotensive response elicited by acute aerobic exercise and sleep quality can impact this dipping response. Purpose: The purpose of this study was to investigate the effects of aerobic exercise timing on circadian BP changes and sleep architecture. Materials and methods: Twenty prehypertensive subjects completed the study. During four test sessions, participants first completed a graded exercise test to exhaustion and then performed 30 minutes of treadmill exercise at 7 am (7A, 1 pm (1P, and 7 pm (7P in a random, counterbalanced order at 65% of the heart rate obtained at peak oxygen uptake. An ambulatory cuff was used to monitor BP responses during 24 hours following exercise, and an ambulatory sleep-monitoring headband was worn during sleep following each session. Results: Aerobic exercise at 7A invoked a greater dip in nocturnal systolic BP than exercise at 1P or 7P, although the greatest dip in nocturnal diastolic BP occurred following 7P. Compared to 1P, 7A also invoked greater time spent in deep sleep. Conclusion: These data indicate that early morning may be the most beneficial time to engage in aerobic exercise to enhance nocturnal BP changes and quality of sleep. Keywords: nocturnal dipping, prehypertension, aerobic exercise

Workplace bullying, sleep problems and leisure-time physical activity: a prospective cohort study.

Science.gov (United States)

Hansen, Åse Marie; Gullander, Maria; Hogh, Annie; Persson, Roger; Kolstad, Henrik A; Willert, Morten Vejs; Bonde, Jens Peter; Kaerlev, Linda; Rugulies, Reiner; Grynderup, Matias Brødsgaard

2016-01-01

Workplace bullying is a potent stressor that may increase sleep problems. Since physical fitness improves resilience to stress, it seems plausible that recreational physical activities may moderate the association between bullying and sleep. The study aimed to examine prospectively whether (i) bullying increases the risk of sleep problems, and (ii) the association between bullying and sleep problems is moderated by leisure-time physical activity (LTPA). The study sample comprised a cohort of public and private sector employees, who were enrolled into the Work Bullying and Harassment (WBH) cohort (N=3278) or the Psychosocial Risk Factors for Stress and Mental Disease (PRISME) cohort (N=4455). We measured workplace bullying using one question that was preceded by a definition of bullying. We used the Karolinska sleep questionnaire to assess sleep problems. The number of hours per week spent on LTPA estimated the degree of physical activity. Workplace bullying at baseline (T1) was associated with awakening problems and lack of restful sleep at follow-up (T2) but not with overall sleep problems and disturbed sleep. T1-LTPA did not moderate the association between T1-workplace bullying and T2-sleep problems. We found support that workplace bullying is related to development of T2-sleep problems, but this association seems not to be modified by LTPA.

Effects of school start time on students' sleep duration, daytime sleepiness, and attendance: a meta-analysis.

Science.gov (United States)

Bowers, Jennifer M; Moyer, Anne

2017-12-01

Research conducted over the past three decades finds that many children and adolescents do not meet recommended sleep guidelines. Lack of sleep is a predictor of a number of consequences, including issues at school such as sleepiness and tardiness. Considering the severity of this public health issue, it is essential to understand more about the factors that may compromise children's and adolescents' sleep. This meta-analysis examined the effects of school start time (SST) on sleep duration of students by aggregating the results of five longitudinal studies and 15 cross-sectional comparison group studies. Results indicated that later starting school times are associated with longer sleep durations. Additionally, later start times were associated with less daytime sleepiness (7 studies) and tardiness to school (3 studies). However, methodological considerations, such as a need for more longitudinal primary research, lead to a cautious interpretation. Overall, this systematic analysis of SST studies suggests that delaying SST is associated with benefits for students' sleep and, thus, their general well-being. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

Sleep Applications to Assess Sleep Quality.

Science.gov (United States)

Fietze, Ingo

2016-12-01

This article highlights the potential uses that smartphone applications may have for helping those with sleep problems. Applications in smartphones offer the promised possibility of detection of sleep. From the author's own experience, one can also conclude that sleep applications are approximately as good as polysomnography in detection of sleep time, similar to the conventional wearable actimeters. In the future, sleep applications will help to further enhance awareness of sleep health and to distinguish those who actually poorly and only briefly sleep from those who suffer more likely from paradox insomnia. Copyright © 2016 Elsevier Inc. All rights reserved.

The effect of sleep quality on academic performance is mediated by Internet use time: DADOS study.

Science.gov (United States)

Adelantado-Renau, Mireia; Diez-Fernandez, Ana; Beltran-Valls, Maria Reyes; Soriano-Maldonado, Alberto; Moliner-Urdiales, Diego

2018-05-19

The aims of the present study were to analyze the association of sleep patterns with academic and cognitive performance in adolescents, and to test the potential mediating effect of different activities of screen media usage on this association. A sample of 269 adolescents (140 boys) aged 14 years from the baseline data of the Deporte, ADOlescencia y Salud study completed questionnaires about sleep quality, cognitive performance, and leisure-time sedentary behaviors. Sleep duration was objectively computed using a wrist-worn GENEActiv accelerometer and academic performance was analyzed through school records. Sleep quality (but not sleep duration) was associated with all the academic performance indicators (all p<0.05). Analysis of covariance revealed higher grades among adolescents with better sleep quality (PSQI≤5; all p<0.05). These analyses showed no differences regarding cognitive performance. Internet use time was revealed as a mediator of the association between sleep quality and academic performance, being significant for all academic performance indicators (P M ranging from 15.5% to 16.0%). The association between sleep quality and academic performance in adolescents is mediated by time of Internet use. Overall, reducing Internet use in adolescents could be an achievable intervention for improving sleep quality, with potentially positive effects on academic performance. Copyright © 2018 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Sleep timing is more important than sleep length or quality for medical school performance

NARCIS (Netherlands)

Genzel, L.K.E.; Ahrberg, K.; Roselli, C.; Niedermaier, S.; Steiger, A.; Dresler, M.; Roenneberg, T.

2013-01-01

Overwhelming evidence supports the importance of sleep for memory consolidation. Medical students are often deprived of sufficient sleep due to large amounts of clinical duties and university load, we therefore investigated how study and sleep habits influence university performance. We performed a

Sleep and Sleepiness among First-Time Postpartum Parents: A Field- and Laboratory-Based Multimethod Assessment

Science.gov (United States)

Insana, Salvatore P.; Montgomery-Downs, Hawley E.

2012-01-01

The study aim was to compare sleep, sleepiness, fatigue, and neurobehavioral performance among first-time mothers and fathers during their early postpartum period. Participants were 21 first-time postpartum mother-father dyads (N=42) and seven childless control dyads (N=14). Within their natural environment, participants completed one week of wrist actigraphy monitoring, along with multi-day self-administered sleepiness, fatigue, and neurobehavioral performance measures. The assessment week was followed by an objective laboratory based test of sleepiness. Mothers obtained more sleep compared to fathers, but mothers’ sleep was more disturbed by awakenings. Fathers had greater objectively measured sleepiness than mothers. Mothers and fathers did not differ on subjectively measured sleep quality, sleepiness, or fatigue; however, mothers had worse neurobehavioral performance than fathers. Compared to control dyads, postpartum parents experienced greater sleep disturbance, sleepiness, and sleepiness associated impairments. Study results inform social policy, postpartum sleep interventions, and research on postpartum family systems and mechanisms that propagate sleepiness. PMID:22553114

Class start times, sleep, and academic performance in college: a path analysis.

Science.gov (United States)

Onyper, Serge V; Thacher, Pamela V; Gilbert, Jack W; Gradess, Samuel G

2012-04-01

Path analysis was used to examine the relationship between class start times, sleep, circadian preference, and academic performance in college-aged adults. Consistent with observations in middle and high school students, college students with later class start times slept longer, experienced less daytime sleepiness, and were less likely to miss class. Chronotype was an important moderator of sleep schedules and daytime functioning; those with morning preference went to bed and woke up earlier and functioned better throughout the day. The benefits of taking later classes did not extend to academic performance, however; grades were somewhat lower in students with predominantly late class schedules. Furthermore, students taking later classes were at greater risk for increased alcohol consumption, and among all the factors affecting academic performance, alcohol misuse exerted the strongest effect. Thus, these results indicate that later class start times in college, while allowing for more sleep, also increase the likelihood of alcohol misuse, ultimately impeding academic success.

Sleep Management on Multiple Machines for Energy and Flow Time

DEFF Research Database (Denmark)

Chan, Sze-Hang; Lam, Tak-Wah; Lee, Lap Kei

2011-01-01

In large data centers, determining the right number of operating machines is often non-trivial, especially when the workload is unpredictable. Using too many machines would waste energy, while using too few would affect the performance. This paper extends the traditional study of online flow-time...... scheduling on multiple machines to take sleep management and energy into consideration. Specifically, we study online algorithms that can determine dynamically when and which subset of machines should wake up (or sleep), and how jobs are dispatched and scheduled. We consider schedules whose objective...... is to minimize the sum of flow time and energy, and obtain O(1)-competitive algorithms for two settings: one assumes machines running at a fixed speed, and the other allows dynamic speed scaling to further optimize energy usage. Like the previous work on the tradeoff between flow time and energy, the analysis...

Benefits of Sleep Extension on Sustained Attention and Sleep Pressure Before and During Total Sleep Deprivation and Recovery.

Science.gov (United States)

Arnal, Pierrick J; Sauvet, Fabien; Leger, Damien; van Beers, Pascal; Bayon, Virginie; Bougard, Clément; Rabat, Arnaud; Millet, Guillaume Y; Chennaoui, Mounir

2015-12-01

To investigate the effects of 6 nights of sleep extension on sustained attention and sleep pressure before and during total sleep deprivation and after a subsequent recovery sleep. Subjects participated in two experimental conditions (randomized cross-over design): extended sleep (EXT, 9.8 ± 0.1 h (mean ± SE) time in bed) and habitual sleep (HAB, 8.2 ± 0.1 h time in bed). In each condition, subjects performed two consecutive phases: (1) 6 nights of either EXT or HAB (2) three days in-laboratory: baseline, total sleep deprivation and after 10 h of recovery sleep. Residential sleep extension and sleep performance laboratory (continuous polysomnographic recording). 14 healthy men (age range: 26-37 years). EXT vs. HAB sleep durations prior to total sleep deprivation. Total sleep time and duration of all sleep stages during the 6 nights were significantly higher in EXT than HAB. EXT improved psychomotor vigilance task performance (PVT, both fewer lapses and faster speed) and reduced sleep pressure as evidenced by longer multiple sleep latencies (MSLT) at baseline compared to HAB. EXT limited PVT lapses and the number of involuntary microsleeps during total sleep deprivation. Differences in PVT lapses and speed and MSLT at baseline were maintained after one night of recovery sleep. Six nights of extended sleep improve sustained attention and reduce sleep pressure. Sleep extension also protects against psychomotor vigilance task lapses and microsleep degradation during total sleep deprivation. These beneficial effects persist after one night of recovery sleep. © 2015 Associated Professional Sleep Societies, LLC.

The relationship between sleep time and self-rated health: an analysis based on Italian survey data

Directory of Open Access Journals (Sweden)

Guido Citoni

2014-06-01

Full Text Available Background: a growing and broadly discussed literature has shown that the relationship between sleep duration and health is not linear. Not only are insomnia and insufficient sleep harmful to one’s health, but excessive sleep too is also not beneficial. This study tests the association between selfrated state of health and the duration and pattern of sleep: we discuss the losses and costs in terms of quality of life deriving from excessive sleep time.Methods: we use an ordered probit specification, applied to the Italian Survey on the Use of Time (sample of Italians aged fifteen and over who keep a diary for a working day.Results: we show that greater sleep duration is negatively correlated both with self-reported state of health and with self-reported health satisfaction, while respondents’ subjective perceptions of too much and too little sleep are associated with health conditions in the usual u-shaped way.Conclusions: the negative impact of long sleep on self-reported health is confirmed. However, the effect of short sleep on health conditions is positive, while a measure of decreasing sleep quality - comprising number of interruptions of sleep, insomnia and napping - is correlated to some extent with decreasing health. The public health consequences are still to be explored: the potential gains from sleep restriction are substantial, but little is known about the causal link or the risks. Further research is needed before taking policy decisions.

Concurrent Associations between Physical Activity, Screen Time, and Sleep Duration with Childhood Obesity.

Science.gov (United States)

Laurson, Kelly R; Lee, Joey A; Gentile, Douglas A; Walsh, David A; Eisenmann, Joey C

2014-01-01

Aim. To examine the simultaneous influence of physical activity, screen time, and sleep duration recommendations on the odds of childhood obesity (including overweight). Methods. Physical activity was assessed via pedometer and screen time, and sleep duration were assessed via survey in a cross sectional sample of 674 children (aged 7-12 years) from two Midwestern communities in the fall of 2005. Participants were cross tabulated into four groups depending on how many recommendations were being met (0, 1, 2, or all 3). Linear and logistic regression were used to examine the influence of physical activity, screen time and sleep duration on obesity and interactions among the three variables. Results. Children achieving all three recommendations simultaneously (9.2% of total sample) were the least likely to be obese. Approximately 16% of boys and 9% of girls achieving all recommendations were overweight or obese compared to 53% of boys and 42.5% of girls not achieving any. Conclusions. The odds of obesity increased in a graded manner for each recommendation which was not met. Meeting all three recommendations appears to have a protective effect against obesity. Continued efforts are warranted to promote healthy lifestyle behaviors that include meeting physical activity, screen time, and sleep duration recommendations concurrently.

Children benefit differently from night- and day-time sleep in motor learning.

Science.gov (United States)

Yan, Jin H

2017-08-01

Motor skill acquisition occurs while practicing (on-line) and when asleep or awake (off-line). However, developmental questions still remain about whether children of various ages benefit similarly or differentially from night- and day-time sleeping. The likely circadian effects (time-of-day) and the possible between-test-interference (order effects) associated with children's off-line motor learning are currently unknown. Therefore, this study examines the contributions of over-night sleeping and mid-day napping to procedural skill learning. One hundred and eight children were instructed to practice a finger sequence task using computer keyboards. After an equivalent 11-h interval in one of the three states (sleep, nap, wakefulness), children performed the same sequence in retention tests and a novel sequence in transfer tests. Changes in the movement time and sequence accuracy were evaluated between ages (6-7, 8-9, 10-11years) during practice, and from skill training to retrievals across three states. Results suggest that night-time sleeping and day-time napping improved the tapping speed, especially for the 6-year-olds. The circadian factor did not affect off-line motor learning in children. The interference between the two counter-balanced retrieval tests was not found for the off-line motor learning. This research offers possible evidence about the age-related motor learning characteristics in children and a potential means for enhancing developmental motor skills. The dynamics between age, experience, memory formation, and the theoretical implications of motor skill acquisition are discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

Decreases in self-reported sleep duration among U.S. adolescents 2009-2015 and association with new media screen time.

Science.gov (United States)

Twenge, Jean M; Krizan, Zlatan; Hisler, Garrett

2017-11-01

Insufficient sleep among adolescents carries significant health risks, making it important to determine social factors that change sleep duration. We sought to determine whether the self-reported sleep duration of U.S. adolescents changed between 2009 and 2015 and examine whether new media screen time (relative to other factors) might be responsible for changes in sleep. We drew from yearly, nationally representative surveys of sleep duration and time use among adolescents conducted since 1991 (Monitoring the Future) and 2007 (Youth Risk Behavior Surveillance System of the Centers for Disease Control; total N = 369,595). Compared to 2009, adolescents in 2015 were 16%-17% more likely to report sleeping less than 7 h a night on most nights, with an increase in short sleep duration after 2011-2013. New media screen time (electronic device use, social media, and reading news online) increased over this time period and was associated with increased odds of short sleep duration, with a clear exposure-response relationship for electronic devices after 2 or more hours of use per day. Other activities associated with short sleep duration, such as homework time, working for pay, and TV watching, were relatively stable or reduced over this time period, making it unlikely that these activities caused the sudden increase in short sleep duration. Increased new media screen time may be involved in the recent increases (from 35% to 41% and from 37% to 43%) in short sleep among adolescents. Public health interventions should consider electronic device use as a target of intervention to improve adolescent health. Copyright © 2017 Elsevier B.V. All rights reserved.

RF start-up and sustainment experiments on the TST-2-K spherical tokamak

International Nuclear Information System (INIS)

Ejiri, A.; Takase, Y.; Kasahara, H.; Yamada, T.; Hanada, K.; Sato, K. N.; Zushi, H.; Nakamura, K.; Sakamoto, M.; Idei, H.; Hasegawa, M.; Iyomasa, A.; Imamura, N.; Esaki, K.; Kitaguchi, M.; Sasaki, K.; Hoshika, H.; Mitarai, O.; Nishino, N.

2006-01-01

Plasma start-up and sustainment without an inductive field have been studied in the TST-2-K spherical tokamak using high power RF sources (8.2 GHz/up to 170 kW). Steady state discharges with a plasma current of 4 kA were achieved. The line integrated density was about 3 x 10 17 m -2 and the electron temperature was 160 eV. A truncated equilibrium was introduced to reproduce magnetic measurements. It was found that a positive Pfirsch-Schlueter current in the open field line region at the outboard boundary makes a significant contribution to the current. Insensitivity of the current to variations in the vertical field and RF power variation was also found

Adolescents' sleep behaviors and perceptions of sleep.

Science.gov (United States)

Noland, Heather; Price, James H; Dake, Joseph; Telljohann, Susan K

2009-05-01

Sleep duration affects the health of children and adolescents. Shorter sleep durations have been associated with poorer academic performance, unintentional injuries, and obesity in adolescents. This study extends our understanding of how adolescents perceive and deal with their sleep issues. General education classes were randomly selected from a convenience sample of three high schools in the Midwest. Three hundred eighty-four ninth- to twelfth-grade students (57%) completed a self-administered valid and reliable questionnaire on sleep behaviors and perceptions of sleep. Most respondents (91.9%) obtained inadequate sleep (sleep each week night. The majority indicated that not getting enough sleep had the following effects on them: being more tired during the day (93.7%), having difficulty paying attention (83.6%), lower grades (60.8%), increase in stress (59.0%), and having difficulty getting along with others (57.7%). Some students reported engaging in harmful behaviors to help them sleep: taking sleeping pills (6.0%), smoking a cigarette to relax (5.7%), and drinking alcohol in the evening (2.9%). Students who received fewer hours of sleep were significantly more likely to report being stressed (p = .02) and were more likely to be overweight (p = .04). Inadequate sleep time may be contributing to adolescent health problems such as increased stress and obesity. Findings indicate a need for sleep hygiene education for adolescents and their parents. A long-term solution to chronic sleep deprivation among high school students could include delaying high school start times, such as was done successfully in the Minneapolis Public School District.

Sleep Disorders

Science.gov (United States)

... the day, even if you have had enough sleep? You might have a sleep disorder. The most common kinds are Insomnia - a hard time falling or staying asleep Sleep apnea - breathing interruptions during sleep Restless legs syndrome - ...

Variable School Start Times and Middle School Student's Sleep Health and Academic Performance.

Science.gov (United States)

Lewin, Daniel S; Wang, Guanghai; Chen, Yao I; Skora, Elizabeth; Hoehn, Jessica; Baylor, Allison; Wang, Jichuan

2017-08-01

Improving sleep health among adolescents is a national health priority and implementing healthy school start times (SSTs) is an important strategy to achieve these goals. This study leveraged the differences in middle school SST in a large district to evaluate associations between SST, sleep health, and academic performance. This cross-sectional study draws data from a county-wide surveillance survey. Participants were three cohorts of eighth graders (n = 26,440). The school district is unique because SST ranged from 7:20 a.m. to 8:10 a.m. Path analysis and probit regression were used to analyze associations between SST and self-report measures of weekday sleep duration, grades, and homework controlling for demographic variables (sex, race, and socioeconomic status). The independent contributions of SST and sleep duration to academic performance were also analyzed. Earlier SST was associated with decreased sleep duration (χ 2  = 173, p academic performance, and academic effort. Path analysis models demonstrated the independent contributions of sleep duration, SST, and variable effects for demographic variables. This is the first study to evaluate the independent contributions of SST and sleep to academic performance in a large sample of middle school students. Deficient sleep was prevalent, and the earliest SST was associated with decrements in sleep and academics. These findings support the prioritization of policy initiatives to implement healthy SST for younger adolescents and highlight the importance of sleep health education disparities among race and gender groups. Copyright © 2017 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

International aircrew sleep and wakefulness after multiple time zone flights - A cooperative study

Science.gov (United States)

Graeber, R. Curtis; Lauber, John K.; Connell, Linda J.; Gander, Philippa H.

1986-01-01

An international research team has carried out an electroencephalographic study of sleep and wakefulness in flight crews operating long-haul routes across seven or eight time zones. Following baseline recordings, volunteer crews (n = 56) from four airlines spent their first outbound layover at a sleep laboratory. This paper provides an overview of the project's history, its research design, and the standardization of procedures. The overall results are remarkably consistent among the four participating laboratories and strongly support the feasibility of cooperative international sleep research in the operational arena.

[Sleeping habits and sleep disorders during adolescence: relation to school performance].

Science.gov (United States)

Salcedo Aguilar, F; Rodríguez Almonacid, F M; Monterde Aznar, M L; García Jiménez, M A; Redondo Martínez, P; Marcos Navarro, A I

2005-05-15

To determine the prevalence of sleep disorders in adolescence. To describe sleeping habits of adolescents in relation to sleep disorders and associated factors. To determine the relation between sleep disorders/inappropiate sleeping habits and school performance. Observational, descriptive, cross-sectional study. Secondary school of Cuenca (city in Spain). 1293 school children of first and fourth curses of secondary education. Structured questionnaire with opened and closed questions on sleeping habits during weekdays and at weekends and sleep disorders to be answered by the adolescents anonymously and on their own. Student's school performance with relation with to sleeping habits and sleep disorders were determined. 1155 students out of 1293 (response rate 89.33%) answered the questionnaire, 537 (45.9%) boys and 618 (54.1%) girls, 14 years old on average (between 11-18 years). On weekdays students went to bed at 23.17 h and got up at 7.46 h (average sleeping time =8 hours and 18 minutes). At weekends they went to bed at 1.02 h and got up at 10.42 h (average sleeping time =9 hours and 40 minutes). 45.4% of students said to sleep badly on Sunday night's. On average the number of subjects failed in class is higher with adolescents who complain about sleep (2.28 vs 1.91; P=.04), who are tired at waking up time (2.17 vs 1.97; P=.048) and who have morning sleepiness (2.17 vs 1.75; P=.004). Schools hours cause deficit sleeping time during weekdays which is partly made up for at weekend. At weekends there is an interruption of the adolescent's sleeping habits. School performance of adolescents with sleep disorders is lower.

Poor sleep quality predicts deficient emotion information processing over time in early adolescence.

Science.gov (United States)

Soffer-Dudek, Nirit; Sadeh, Avi; Dahl, Ronald E; Rosenblat-Stein, Shiran

2011-11-01

There is deepening understanding of the effects of sleep on emotional information processing. Emotion information processing is a key aspect of social competence, which undergoes important maturational and developmental changes in adolescence; however, most research in this area has focused on adults. Our aim was to test the links between sleep and emotion information processing during early adolescence. Sleep and facial information processing were assessed objectively during 3 assessment waves, separated by 1-year lags. Data were obtained in natural environments-sleep was assessed in home settings, and facial information processing was assessed at school. 94 healthy children (53 girls, 41 boys), aged 10 years at Time 1. N/A. Facial information processing was tested under neutral (gender identification) and emotional (emotional expression identification) conditions. Sleep was assessed in home settings using actigraphy for 7 nights at each assessment wave. Waking > 5 min was considered a night awakening. Using multilevel modeling, elevated night awakenings and decreased sleep efficiency significantly predicted poor performance only in the emotional information processing condition (e.g., b = -1.79, SD = 0.52, confidence interval: lower boundary = -2.82, upper boundary = -0.076, t(416.94) = -3.42, P = 0.001). Poor sleep quality is associated with compromised emotional information processing during early adolescence, a sensitive period in socio-emotional development.

Sleep Insufficiency, Sleep Health Problems and Performance in High School Students

Directory of Open Access Journals (Sweden)

Xue Ming

2011-01-01

Full Text Available A survey on sleep schedule, sleep health, school performance and school start times was conducted in 1,941 adolescents. A high level of early and circadian-disadvantaged sleep/wake schedules during weekdays was observed. Shorter sleep duration on weekdays was reported, especially in upper classmen. Complaints of inadequate sleep and sleepiness during weekdays, alarm clock use, and napping were prevalent. Night awakening and prolonged sleep onset were common and associated with poor school performance. Students with a sleep length of less than 7 hours on both weekdays and weekends exhibited poorer performance, while those who made up this sleep loss on weekends did not. The total number of poor sleep factors in an individual also correlated with poor school performance. Earlier school start times were associated with a perception of poor sleep quality, shorter sleep duration and more sleep health problems. We conclude that sleep inadequacies and sleep health problems were prevalent in this population, especially in those who started school earlier in the morning, and that these poor sleep factors were associated with school performance.

Sleep disorders and work performance: findings from the 2008 National Sleep Foundation Sleep in America poll.

Science.gov (United States)

Swanson, Leslie M; Arnedt, J Todd; Rosekind, Mark R; Belenky, Gregory; Balkin, Thomas J; Drake, Christopher

2011-09-01

Chronic sleep deprivation is common among workers, and has been associated with negative work outcomes, including absenteeism and occupational accidents. The objective of the present study is to characterize reciprocal relationships between sleep and work. Specifically, we examined how sleep impacts work performance and how work affects sleep in individuals not at-risk for a sleep disorder; assessed work performance outcomes for individuals at-risk for sleep disorders, including insomnia, obstructive sleep apnea (OSA) and restless legs syndrome (RLS); and characterized work performance impairments in shift workers (SW) at-risk for shift work sleep disorders relative to SW and day workers. One-thousand Americans who work 30 h per week or more were asked questions about employment, work performance and sleep in the National Sleep Foundation's 2008 Sleep in America telephone poll. Long work hours were associated with shorter sleep times, and shorter sleep times were associated with more work impairments. Thirty-seven percent of respondents were classified as at-risk for any sleep disorder. These individuals had more negative work outcomes as compared with those not at-risk for a sleep disorder. Presenteeism was a significant problem for individuals with insomnia symptoms, OSA and RLS as compared with respondents not at-risk. These results suggest that long work hours may contribute to chronic sleep loss, which may in turn result in work impairment. Risk for sleep disorders substantially increases the likelihood of negative work outcomes, including occupational accidents, absenteeism and presenteeism. © 2010 European Sleep Research Society.

Heritability of siesta and night-time sleep as continuously assessed by a circadian-related integrated measure

OpenAIRE

Lopez-Minguez, J.; Morosoli, J. J.; Madrid, J. A.; Garaulet, M.; Ordoñana, J. R.

2017-01-01

Siesta is a relevant aspect of sleep due to its posited relationship with health or cognitive function. However, unlike night-time sleep, studies about daytime-sleep determinants and characteristics are scarce, and the genetic/environmental structure of siesta is still unknown. Our aim was to explore the relative contribution of genetic and environmental factors to variation in sleep-wake rhythm, measured by a continuous assessment of temperature-activity-position (TAP), which allows for diur...

Sleep-time sizing and scheduling in green passive optical networks

KAUST Repository

Elrasad, Amr; Khafagy, Mohammad G.; Shihada, Basem

2012-01-01

of traffic, control and data. Control traffic are delay intolerant with higher priority than the data traffic. Closed form model for average ONU sleeping time and end-to-end data traffic delay are presented and evaluated. Our framework decouples

Sleep and Mental Health in Undergraduate Students with Generally Healthy Sleep Habits.

Science.gov (United States)

Milojevich, Helen M; Lukowski, Angela F

2016-01-01

Whereas previous research has indicated that sleep problems tend to co-occur with increased mental health issues in university students, relatively little is known about relations between sleep quality and mental health in university students with generally healthy sleep habits. Understanding relations between sleep and mental health in individuals with generally healthy sleep habits is important because (a) student sleep habits tend to worsen over time and (b) even time-limited experience of sleep problems may have significant implications for the onset of mental health problems. In the present research, 69 university students with generally healthy sleep habits completed questionnaires about sleep quality and mental health. Although participants did not report clinically concerning mental health issues as a group, global sleep quality was associated with mental health. Regression analyses revealed that nighttime sleep duration and the frequency of nighttime sleep disruptions were differentially related to total problems and clinically-relevant symptoms of psychological distress. These results indicate that understanding relations between sleep and mental health in university students with generally healthy sleep habits is important not only due to the large number of undergraduates who experience sleep problems and mental health issues over time but also due to the potential to intervene and improve mental health outcomes before they become clinically concerning.

A Time for Learning and a Time for Sleep : The Effect of Sleep Deprivation on Contextual Fear Conditioning at Different Times of the Day

NARCIS (Netherlands)

Hagewoud, Roelina; Whitcomb, Shamiso N.; Heeringa, Amarins N.; Havekes, Robbert; Koolhaas, Jaap M.; Meerlo, Peter

2010-01-01

Study Objectives: Sleep deprivation negatively affects memory consolidation, especially in the case of hippocampus-dependent memories. Studies in rodents have shown that 5 hours of sleep deprivation immediately following footshock exposure selectively impairs the formation of a contextual fear

Effects of zolpidem on sleep architecture, night time ventilation, daytime vigilance and performance in heavy snorers.

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Quera-Salva, M A; McCann, C; Boudet, J; Frisk, M; Borderies, P; Meyer, P

1994-01-01

1. In a double-blind, crossover, placebo controlled trial, zolpidem 10 mg, a new imidazopyridine hypnotic drug, was administered in a single dose to 10 healthy non-obese heavy snorers. 2. Nocturnal polysomnography showed that zolpidem increased total sleep time, sleep efficiency and the percentage of stage 2. 3. Respiratory monitoring showed that zolpidem did not modify the percentage of total sleep time spent snoring. The percentages of total sleep time with a SaO2 < 4% of the baseline value and with a SaO2 < 90% and the mean SaO2 were also unchanged with zolpidem. The respiratory disturbance index was modestly increased by zolpidem although in all but one subject it remained < 5 with both treatments. 4. Zolpidem intake did not impair daytime vigilance and performance evaluated the day after. PMID:7917771

Sleep timing and child and parent outcomes in Australian 4-9-year-olds: a cross-sectional and longitudinal study.

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Quach, Jon; Price, Anna M H; Bittman, Michael; Hiscock, Harriet

2016-06-01

The aim of this study is to use national Australian time-diary data to examine both (1) cross-sectionally and (2) longitudinally whether being late versus early to sleep or wake is associated with poorer child behavior, quality of life, learning, cognition and weight status, and parental mental health. Data from the first three waves of the Longitudinal Study of Australian Children were taken. A national representative sample of 4983 4-5-year-olds, recruited in 2004 from the Australian Medicare database and followed up biennially, was taken; 3631 had analyzable sleep information and a concurrent measure of health and well-being for at least one wave. Parents completed 24-h child time-use diaries for one week and one weekend day at each wave. Using median splits, sleep timing was categorized into early-to-sleep/early-to-wake (EE), early-to-sleep/late-to-wake (EL), late-to-sleep/early-to-wake (LE), and late-to-sleep/late-to-wake (LL) at each wave. The outcomes included parent-reported child behavior, health-related quality of life, maternal/paternal mental health, teacher-reported child language, literacy, mathematical thinking, and approach to learning. The study assessed child body mass index and girth. (1) Using EE as the comparator, linear regression analyses revealed that being late-to-sleep was associated with poorer child quality of life from 6 to 9 years and maternal mental health at 6-7 years. There was inconsistent or no evidence for associations between sleep timing and all other outcomes. (2) Using the count of the number of times (waves) at which a child was categorized as late-to-sleep (range 0-3), longitudinal analyses demonstrated that there was a cumulative effect of late-to-sleep profiles on poorer child and maternal outcomes at the child age of 8-9 years. Examined cross-sectionally, sleep timing is a driver of children's quality of life and maternal depression. Examined longitudinally, there appears to be cumulative and adverse relationships

Sleep Disturbances in Newborns

OpenAIRE

Yasova Barbeau, Daphna; Weiss, Michael D.

2017-01-01

The purpose of this review is to serve as an introduction to understanding sleep in the fetus, the preterm neonate and the term neonate. Sleep appears to have numerous important roles, particularly in the consolidation of new information. The sleep cycle changes over time, neonates spend the most time in active sleep and have a progressive shortening of active sleep and lengthening of quiet sleep. Additionally, the sleep cycle is disrupted by many things including disease state and environmen...

Differences in sleep habits, study time, and academic performance between US-born and foreign-born college students.

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Eliasson, Arne H; Eliasson, Arn H; Lettieri, Christopher J

2017-05-01

To inform the design of a sleep improvement program for college students, we assessed academic performance, sleep habits, study hours, and extracurricular time, hypothesizing that there would be differences between US-born and foreign-born students. Questionnaires queried participants on bedtimes, wake times, nap frequency, differences in weekday and weekend sleep habits, study hours, grade point average, time spent at paid employment, and other extracurricular activities. Comparisons were made using chi square tests for categorical data and t tests for continuous data between US-born and foreign-born students. Of 120 participants (55 % women) with racial diversity (49 whites, 18 blacks, 26 Hispanics, 14 Asians, and 13 other), 49 (41 %) were foreign-born. Comparisons between US-born and foreign-born students showed no differences in average age or gender though US-born had more whites. There were no differences between US-born and foreign-born students for grade point averages, weekday bedtimes, wake times, or total sleep times. However, US-born students averaged 50 min less study time per day (p = 0.01), had almost 9 h less paid employment per week (14.5 vs 23.4 h per week, p = 0.001), and stayed up to socialize more frequently (63 vs 43 %, p = 0.03). Foreign-born students awakened an hour earlier and averaged 40 min less sleep per night on weekends. Cultural differences among college students have a profound effect on sleep habits, study hours, and extracurricular time. The design of a sleep improvement program targeting a population with diverse cultural backgrounds must factor in such behavioral variations in order to have relevance and impact.

Sleep benefit in Parkinson's disease: time to revive an enigma?

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van Gilst, Merel M; Louter, Maartje; Baumann, Christian R; Bloem, Bastiaan R; Overeem, Sebastiaan

2012-01-01

Some patients with Parkinson's disease (PD) reportedly experience 'sleep benefit': an improved motor functioning upon awaking in the morning. In this questionnaire study, 114 out of 243 consecutive outpatients with PD (46.9%) subjectively experienced sleep benefit. Among those patients that regularly took an afternoon nap, 33.7% experienced sleep benefit after the nap as well. Between patients with and without sleep benefit, there were no differences in demographic or clinical variables, including age, disease duration, dopaminergic treatment, and nocturnal sleep quality. Sleep benefit remains an intriguing but elusive phenomenon, which deserves renewed attention and further research.

Developmental characteristics of temporal sharp transients in the EEG of normal preterm and term newborns

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Nunes Magda Lahorgue

2003-01-01

Full Text Available OBJECTIVE: To describe developmental characteristics, morphological aspects and incidence of temporal sharp transients (TST in normal preterm and term newborns at matched conceptional ages (CA. METHOD: Neonatal EEGs from two groups of normal newborns were evaluated in order to identify and characterize TST. Group I (n=40 consisted of newborns from 34 to 40 weeks of gestational age (GA that were submitted to a single EEG between 24 and 48 hours of life. Group II consisted of 10 preterm newborns with GA between 30-32 weeks, followed with a weekly EEG until they reached term. Morphology of TST was divided in 3 groups (temporal sawtooth, isolated transients or repetitive transients. TST index, density and total number were calculated in each polysomnography and related to sleep stages and CA. Laterality (right/left was also evaluated. The groups were compared at 34, 36, 38 and 40 weeks of CA. RESULTS: TST index and density decreased with the increase of CA in both groups (p<0.0001. The temporal sawtooth feature was registered in both groups only at 34 weeks. Although rare, repetitive and isolated TST were the most prevalent morphology between 36 - 40 weeks CA. Significant intragroup difference was observed in the comparison of TST density in REM and transitional sleep in GI. Moreover, isolated TST morphology was significant higher in GI at 34 weeks when compared to the others CA. No intragroup differences were observed on GII. No significant differences between the groups were observed considering TST number, index, density, morphology or laterality, at the matched CA. CONCLUSION: TST are normal features of neonatal EEG, as they are registered in normal newborns. Its incidence varies accordingly to morphology and they tend to disappear following the increase of CA. Temporal sawtooth appears more often in preterm newborns. Our results suggest that TST index, density and morphology variability may be a function of CA.

On-call work: To sleep or not to sleep? It depends.

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Ferguson, Sally A; Paterson, Jessica L; Hall, Sarah J; Jay, Sarah M; Aisbett, Brad

On-call working time arrangements are increasingly common, involve work only in the event of an unpredictable incident and exist primarily outside of standard hours. Like other non-standard working time arrangements, on-call work disrupts sleep and can therefore have negative effects on health, safety and performance. Unlike other non-standard working time arrangements, on-call work often allows sleep opportunities between calls. Any sleep obtained during on-call periods will be beneficial for waking performance. However, there is evidence that sleep while on call may be of substantially reduced restorative value because of the expectation of receiving the call and apprehension about missing the call. In turn, waking from sleep to respond to a call may be associated with temporary increases in performance impairment. This is dependent on characteristics of both the preceding sleep, the tasks required upon waking and the availability and utility of any countermeasures to support the transition from sleep to wake. In this paper, we critically evaluate the evidence both for and against sleeping during on-call periods and conclude that some sleep, even if it is of reduced quality and broken by repeated calls, is a good strategy. We also note, however, that organisations utilising on-call working time arrangements need to systematically manage the likelihood that on-call sleep can be associated with temporary performance impairments upon waking. Given that the majority of work in this area has been laboratory-based, there is a significant need for field-based investigations of the magnitude of sleep inertia, in addition to the utility of sleep inertia countermeasures. Field studies should include working with subject matter experts to identify the real-world impacts of changes in performance associated with sleeping, or not sleeping, whilst on call.

The impact of Sleep Time-Related Information and Communication Technology (STRICT) on sleep patterns and daytime functioning in American adolescents.

Science.gov (United States)

Polos, Peter G; Bhat, Sushanth; Gupta, Divya; O'Malley, Richard J; DeBari, Vincent A; Upadhyay, Hinesh; Chaudhry, Saqib; Nimma, Anitha; Pinto-Zipp, Genevieve; Chokroverty, Sudhansu

2015-10-01

This cross-sectional study explored the extent and impact of mobile device-based Sleep Time-Related Information and Communication Technology (STRICT) use among American adolescents (N = 3139, 49.3% female, mean age = 13.3 years). Nearly 62% used STRICT after bedtime, 56.7% texted/tweeted/messaged in bed, and 20.8% awoke to texts. STRICT use was associated with insomnia, daytime sleepiness, eveningness, academic underperformance, later bedtimes and shorter sleep duration. Moderation analysis demonstrated that the association between STRICT use and insomnia increased with age, the association between STRICT use and daytime sleepiness decreased with age, and the association between STRICT use and shorter sleep duration decreased with age and was stronger in girls. Insomnia and daytime sleepiness partially mediated the relationship between STRICT use and academic underperformance. Our results illustrate the adverse interactions between adolescent STRICT use and sleep, with deleterious effects on daytime functioning. These worrisome findings suggest that placing reasonable limitations on adolescent STRICT use may be appropriate. Copyright © 2015 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

Effects of adenotonsillectomy on plasma inflammatory biomarkers in obese children with obstructive sleep apnea: A community-based study.

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Kheirandish-Gozal, L; Gileles-Hillel, A; Alonso-Álvarez, M L; Peris, E; Bhattacharjee, R; Terán-Santos, J; Duran-Cantolla, J; Gozal, D

2015-07-01

Obesity and obstructive sleep apnea syndrome (OSA) are highly prevalent and frequently overlapping conditions in children that lead to systemic inflammation, the latter being implicated in the various end-organ morbidities associated with these conditions. To examine the effects of adenotonsillectomy (T&A) on plasma levels of inflammatory markers in obese children with polysomnographically diagnosed OSA who were prospectively recruited from the community. Obese children prospectively diagnosed with OSA, underwent T&A and a second overnight polysomnogram (PSG) after surgery. Plasma fasting morning samples obtained after each of the two PSGs were assayed for multiple inflammatory and metabolic markers including interleukin (IL)-6, IL-18, plasminogen activator inhibitor-1 (PAI-1), monocyte chemoattractant protein-1 (MCP-1), matrix metalloproteinase-9 (MMP-9), adiponectin, apelin C, leptin and osteocrin. Out of 122 potential candidates, 100 obese children with OSA completed the study with only one-third exhibiting normalization of their PSG after T&A (that is, apnea-hypopnea index (AHI) ≤1/hour total sleep time). However, overall significant decreases in MCP-1, PAI-1, MMP-9, IL-18 and IL-6, and increases in adropin and osteocrin plasma concentrations occurred after T&A. Several of the T&A-responsive biomarkers exhibited excellent sensitivity and moderate specificity to predict residual OSA (that is, AHI⩾5/hTST). A defined subset of systemic inflammatory and metabolic biomarkers is reversibly altered in the context of OSA among community-based obese children, further reinforcing the concept on the interactive pro-inflammatory effects of sleep disorders such as OSA and obesity contributing to downstream end-organ morbidities.

Youth Screen Time and Behavioral Health Problems: The Role of Sleep Duration and Disturbances.

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Parent, Justin; Sanders, Wesley; Forehand, Rex

2016-05-01

The purpose of this study was to examine the indirect effect of youth screen time (e.g., television, computers, smartphones, video games, and tablets) on behavioral health problems (i.e., internalizing, externalizing, and peer problems) through sleep duration and disturbances. The authors assessed a community sample of parents with a child in one of the following three developmental stages: young childhood (3-7 yrs; N = 209), middle childhood (8-12 yrs; N = 202), and adolescence (13-17 yrs; N = 210). Path analysis was used to test the hypothesized indirect effect model. Findings indicated that, regardless of the developmental stage of the youth, higher levels of youth screen time were associated with more sleep disturbances, which, in turn, were linked to higher levels of youth behavioral health problems. Children who have increased screen time are more likely to have poor sleep quality and problem behaviors.

School Start Times, Sleep, Behavioral, Health, and Academic Outcomes: A Review of the Literature

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Wheaton, Anne G.; Chapman, Daniel P.; Croft, Janet B.

2016-01-01

Background: Insufficient sleep in adolescents has been shown to be associated with a wide variety of adverse outcomes, from poor mental and physical health to behavioral problems and lower academic grades. However, most high school students do not get sufficient sleep. Delaying school start times for adolescents has been proposed as a policy…

Investigating the associations between work hours, sleep status, and self-reported health among full-time employees.

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Nakata, Akinori

2012-04-01

The extent to which work hours and sleep are associated with self-rated health (SRH) was investigated in full-time employees of small- and medium-scale businesses (SMBs) in a suburb of Tokyo. A total of 2,579 employees (1,887 men and 692 women), aged 18-79 (mean 45) years, in 296 SMBs were surveyed using a self-administered questionnaire from August to December 2002. Work hours, sleep, and SRH were evaluated. Compared with those working 6-8 h/day, participants working >8 to 10 h/day and >10 h/day had significantly higher odds of suboptimal SRH [adjusted odds ratio (aOR) 1.36 and 1.87, respectively]. Similarly, compared with those sleeping 6+ h/day and sufficient sleep, participants with short sleep (work hours with short sleep (aOR 3.30) or insufficient sleep (aOR 3.40) exerted synergistic negative associations on SRH. This study suggests that long work hours and poor sleep and its combination are associated with suboptimal SRH.

Sleep patterns of Japanese preschool children and their parents: implications for co-sleeping.

Science.gov (United States)

Iwata, Sachiko; Iwata, Osuke; Matsuishi, Toyojiro

2013-06-01

The aim of this study was to investigate the direct relationship of sleep schedule and sleep quality variables between healthy preschool children and their parents, focusing on the influence of the difference in bedtime between each other. Forty-seven Japanese 5-year-old children and their primary parent were studied. The parents completed questionnaires including the Epworth Sleepiness Scale and Pittsburgh Sleep Quality Index. The children wore an actigraph for one week. Although sleep patterns of children were generally independent of their parents, late sleep end time and bedtime of children were associated with parents' late sleep end time on weekends. For 87% of children and parents who shared a bedroom, sleep quality was negatively affected by a shorter difference in bedtimes between child and parent, but not by co-sleeping. Sleep behaviours of parents can influence those of their children. For parents and children who share a bedroom, the timing of bedtime rather than co-sleeping may be a key factor in modulating sleep patterns. Trying to get children asleep and subsequently falling asleep at a similar time may disturb parents' sleep quality, which may subsequently affect that of their children. ©2013 Foundation Acta Paediatrica. Published by Blackwell Publishing Ltd.

Non-inductive plasma initiation and plasma current ramp-up on the TST-2 spherical tokamak

International Nuclear Information System (INIS)

Takase, Y.; Ejiri, A.; Oosako, T.; Shinya, T.; Ambo, T.; Furui, H.; Kato, K.; Nakanishi, A.; Sakamoto, T.; Kakuda, H.; Wakatsuki, T.; Hashimoto, T.; Hiratsuka, J.; Kasahara, H.; Kumazawa, R.; Mutoh, T.; Saito, K.; Seki, T.; Moeller, C.P.; Nagashima, Y.

2013-01-01

Plasma current (I p ) start-up in a spherical tokamak (ST) by waves in the lower-hybrid (LH) frequency range was investigated on TST-2. A low current (∼1 kA) ST configuration can be formed by waves over a broad frequency range (21 MHz–8.2 GHz in TST-2), but further I p ramp-up (to ∼10 kA) is most efficient with waves in the LH frequency range. I p ramp-up to 15 kA was achieved with 60 kW of net RF power P RF in the fast wave (FW) polarization at 200 MHz excited by the inductively coupled combline antenna. X-ray measurements showed that the photon flux and temperature are higher in the direction opposite to I p , consistent with acceleration of electrons by a uni-directional RF wave. There is evidence that the LH wave is excited nonlinearly by the FW, based on the frequency spectra measured by magnetic probes. Similar efficiencies of I p ramp-up were obtained with the inductive combline antenna and the dielectric-loaded waveguide array (‘grill’) antenna, and tendencies for the current drive efficiency to increase with plasma current and toroidal field were observed. During operation of the grill antenna, wavevector components were measured by an array of magnetic probes. Results were qualitatively consistent with expectations based on dispersion relations for the FW and the LH wave. A capacitively coupled combline antenna has been developed to improve coupling to the plasma and the wavenumber spectrum of the excited LH wave, and will be tested in 2013. (paper)

On The Settling And Response Times Of Underdamped Second-Order Systems

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Abdul-Fattah Mohamed Ali

2012-01-01

Full Text Available The normalized settling time (ts/t values of oscillatory second order systems, when subjected to a step-change forcing function (SCFF, depend on the sensitivity of the measuring instrument employed to indicate the response (± x%. An attempt is made to mathematically relate ts/t to ± x% utilizing the exact, and a simplified, expression for the lower boundary of the decay envelope (LBDE. The two obtained relationships were tested against the actual ts/t values for a settling bands range of ±1% = ±x% = ±6%, covering a damping coefficient range of 0.1 = ? = 0.65. Although the relationships are not exact, their general trend is a marginal overestimation of ts/t. The relationship based on the simplified LBDE was chosen for being simpler and slightly more accurate of the two. This led to a suggested distinction between ts/t and the normalized response time (tR/t, with the latter assigned the value 5/ ? . The ratio ts/tR can thus be readily established for any ± x% value.ABSTRAK: Masa enapan ternormal (ts/t  nilai ayunan system terbit kedua, apabila fungsi memaksa ubah berperingkat (step-change forcing function (SCFF dijalankan ke atasnya, bergantung kepada kepekaan alat pengukur yang digunakan untuk mengukur respons (± x%. Satu percubaan dijalankan secara matematik untuk mengaitkan ts/t to ± x% dengan mempergunakan ekspresi yang tepat dan mudah, pada sempadan bawah sampul reputan (lower boundary of the decay envelope (LBDE. Dua hubungan yang diperolehi dikaji terhadap nilai ts/t sebenar untuk julat jalur enapan ±1% = ±x% = ±6%, melingkungi julat pekali redaman 0.1 = ? = 0.65. Walaupun hubungannya tidak tepat, trend umum merupakan penganggaran marginal ts/t. Hubungan berdasarkan LBDE adalah berdasarkan  LBDE yang telah dipermudahkan, ia dipilih kerana ianya senang dan agak tepat antara keduanya. Ini mendorong kepada perbezaan yang disarankan antara ts/t  dan waktu respons ternormal (tR/t, dengan nilai 5/ ? yang ditetapkan kemudiannya

Night-time care routine interaction and sleep disruption in adult cardiac surgery.

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Casida, Jesus M; Davis, Jean E; Zalewski, Aaron; Yang, James J

2018-04-01

To explore the context and the influence of night-time care routine interactions (NCRIs) on night-time sleep effectiveness (NSE) and daytime sleepiness (DSS) of patients in the cardiac surgery critical-care and progressive-care units of a hospital. There exists a paucity of empirical data regarding the influence of NCRIs on sleep and associated outcomes in hospitalised adult cardiac surgery patients. An exploratory repeated-measures research design was employed on the data provided by 38 elective cardiac surgery patients (mean age 60.0 ± 15.9 years). NCRI forms were completed by the bedside nurses and patients completed a 9-item Visual Analogue Sleep Scale (100-mm horizontal lines measuring NSE and DSS variables). All data were collected during postoperative nights/days (PON/POD) 1 through 5 and analysed with IBM SPSS software. Patient assessment, medication administration and laboratory/diagnostic procedures were the top three NCRIs reported between midnight and 6:00 a.m. During PON/POD 1 through 5, the respective mean NSE and DSS scores ranged from 52.9 ± 17.2 to 57.8 ± 13.5 and from 27.0 ± 22.6 to 45.6 ± 16.5. Repeated-measures ANOVA showed significant changes in DSS scores (p  .05). Finally, of 8 NCRIs, only 1 (postoperative exercises) was significantly related to sleep variables (r > .40, p disruptions and daytime sleepiness in adult cardiac surgery. Worldwide, acute and critical-care nurses are well positioned to lead initiatives aimed at improving sleep and clinical outcomes in cardiac surgery. © 2018 John Wiley & Sons Ltd.

Time-on-task decrement in vigilance is modulated by inter-individual vulnerability to homeostatic sleep pressure manipulation

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Micheline eMaire

2014-03-01

Full Text Available Under sleep loss, vigilance is reduced and attentional failures emerge progressively. It becomes difficult to maintain stable performance over time, leading to growing performance variability (i.e. state instability in an individual and among subjects. Task duration plays a major role in the maintenance of stable vigilance levels, such that the longer the task, the more likely state instability will be observed. Vulnerability to sleep-loss-dependent performance decrements is highly individual and is also modulated by a polymorphism in the human clock gene PERIOD3 (PER3. By combining two different protocols, we manipulated sleep-wake history by once extending wakefulness for 40 h (high sleep pressure condition and once by imposing a short sleep-wake cycle by alternating 160 min of wakefulness and 80 min naps (low sleep pressure condition in a within-subject design. We observed that homozygous carriers of the long repeat allele of PER3 (PER35/5 experienced a greater time-on-task dependent performance decrement (i.e., a steeper increase in the number of lapses in the Psychomotor Vigilance Task compared to the carriers of the short repeat allele (PER34/4. These genotype-dependent effects disappeared under low sleep pressure conditions, and neither motivation, nor perceived effort accounted for these differences. Our data thus suggest that greater sleep-loss related attentional vulnerability based on the PER3 polymorphism is mirrored by a greater state instability under extended wakefulness in the short compared to the long allele carriers. Our results undermine the importance of time-on-task related aspects when investigating inter-individual differences in sleep loss-induced behavioural vulnerability.

Signals from the brainstem sleep/wake centers regulate behavioral timing via the circadian clock.

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Sabra M Abbott

Full Text Available Sleep-wake cycling is controlled by the complex interplay between two brain systems, one which controls vigilance state, regulating the transition between sleep and wake, and the other circadian, which communicates time-of-day. Together, they align sleep appropriately with energetic need and the day-night cycle. Neural circuits connect brain stem sites that regulate vigilance state with the suprachiasmatic nucleus (SCN, the master circadian clock, but the function of these connections has been unknown. Coupling discrete stimulation of pontine nuclei controlling vigilance state with analytical chemical measurements of intra-SCN microdialysates in mouse, we found significant neurotransmitter release at the SCN and, concomitantly, resetting of behavioral circadian rhythms. Depending upon stimulus conditions and time-of-day, SCN acetylcholine and/or glutamate levels were augmented and generated shifts of behavioral rhythms. These results establish modes of neurochemical communication from brain regions controlling vigilance state to the central circadian clock, with behavioral consequences. They suggest a basis for dynamic integration across brain systems that regulate vigilance states, and a potential vulnerability to altered communication in sleep disorders.

Signals from the brainstem sleep/wake centers regulate behavioral timing via the circadian clock.

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Abbott, Sabra M; Arnold, Jennifer M; Chang, Qing; Miao, Hai; Ota, Nobutoshi; Cecala, Christine; Gold, Paul E; Sweedler, Jonathan V; Gillette, Martha U

2013-01-01

Sleep-wake cycling is controlled by the complex interplay between two brain systems, one which controls vigilance state, regulating the transition between sleep and wake, and the other circadian, which communicates time-of-day. Together, they align sleep appropriately with energetic need and the day-night cycle. Neural circuits connect brain stem sites that regulate vigilance state with the suprachiasmatic nucleus (SCN), the master circadian clock, but the function of these connections has been unknown. Coupling discrete stimulation of pontine nuclei controlling vigilance state with analytical chemical measurements of intra-SCN microdialysates in mouse, we found significant neurotransmitter release at the SCN and, concomitantly, resetting of behavioral circadian rhythms. Depending upon stimulus conditions and time-of-day, SCN acetylcholine and/or glutamate levels were augmented and generated shifts of behavioral rhythms. These results establish modes of neurochemical communication from brain regions controlling vigilance state to the central circadian clock, with behavioral consequences. They suggest a basis for dynamic integration across brain systems that regulate vigilance states, and a potential vulnerability to altered communication in sleep disorders.

Assessing the sleeping habits of patients in a sleep disorder centre: a review of sleep diary accuracy

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Lawrence, Geoffrey

2018-01-01

Background Excessive daytime sleepiness (EDS) is a complaint common to many aspects of medicine. There are primary and secondary causes for EDS, with secondary causes including a large number of common conditions. Primary causes, such as narcolepsy, are much rarer. When assessing for primary hypersomnia, restricted or fragmented sleep must be ruled out. This process involves assessment of sleeping habits using a sleep diary and/or actigraphy. Clinicians are suspicious of the accuracy with which patients use the former. This review aims to evaluate the accuracy of a sleep diary study against the ‘objective gold standard’ actigraphy report. Methods Data from 35 patients at a Sleep Disorder Centre who underwent both a sleep diary and actigraphy study for suspected primary hypersomnia in 2016 was collected. Mean values of four variables were calculated: ‘time of lights out’, ‘time to fall asleep’, ‘time of waking’ and ‘sleep time’. The ‘similarity’ was assessed. This was a term defined in three different ways: if sleep diary values are accurate to within 20, 30 and 60 min respectively. Percentage ‘similarity’, mean time differences and standard deviations (SDs) were calculated for each variable. A paired t-test was also performed to assess the significance of the time differences between the two modalities. Results Least accurate was ‘sleep time’, with 14.7%, 23.5% and 58.8% of patients within 20, 30 and 60 min of the actigraphy respectively. Mean time difference for this variable was 66 min (versus 33, 15 and 22). ‘Time to fall asleep’ was most accurate, with 76.5%, 82.4% and 100% ‘similarity’ respectively. Conclusions The clinically acceptable accuracy has no universal definition, so clinicians must use experience and reasoning to determine this level to interpret this data. The review suggests that some variables are entered with high accuracy, and the diary is low cost and adds subjective information that cannot be gathered

Electrochemical corrosion studies of the TStE 355 fine-grained structural steel in sulfide containing brine

International Nuclear Information System (INIS)

Farvaque-Bera, A.M.; Berg, H. von.

1994-04-01

Previous corrosion studies have shown that the unalloyed fine-grained steel TStE 355 (Material No. 1.0566) is a promising material for the manufacturing of long-lived high-level waste (HLW) containers that could act as a barrier in a rock-salt repository. Considering this fact, further electrochemical corrosion tests were performed in order to determine the influence of sulfide ions (1 -200 ppm), present as salt impurities in disposal relevant NaCl-brine (T = 55 -90 C), on the corrosion behaviour of this steel grade. For comparison, tests were carried out in the sulfide-free brine, too. (orig.) [de

Effects of three hypnotics on the sleep-wakefulness cycle in sleep-disturbed rats.

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Shinomiya, Kazuaki; Shigemoto, Yuki; Omichi, Junji; Utsu, Yoshiaki; Mio, Mitsunobu; Kamei, Chiaki

2004-04-01

New sleep disturbance model in rats is useful for estimating the characteristics of some hypnotics. The present study was undertaken to investigate the utility of a sleep disturbance model by placing rats on a grid suspended over water using three kinds of hypnotics, that is, short-acting benzodiazepine (triazolam), intermediate-acting benzodiazepine (flunitrazepam) and long-acting barbiturate (phenobarbital). Electrodes for measurement of EEG and EMG were implanted into the frontal cortex and the dorsal neck muscle of rats. EEG and EMG were recorded with an electroencephalogram. SleepSign ver.2.0 was used for EEG and EMG analysis. Total times of wakefulness, non-REM and REM sleep were measured from 0900 to 1500 hours. In rats placed on the grid suspended over water up to 1 cm under the grid surface, not only triazolam but also flunitrazepam and phenobarbital caused a shortening of sleep latency. Both flunitrazepam and phenobarbital were effective in increasing of total non-REM sleep time in rats placed on sawdust or the grid, and the effects of both drugs in rats placed on the grid were larger than those in rats placed on sawdust. Measurement of the hourly non-REM sleep time was useful for investigating the peak time and duration of effect of the three hypnotics. Phenobarbital showed a decrease in total REM sleep time in rats placed on the grid, although both triazolam and flunitrazepam were without effect. The present insomnia model can be used as a sleep disturbance model for testing not only the sleep-inducing effects but also the sleep-maintaining effects including non-REM sleep and REM sleep of hypnotics.

Memory processing in great apes: the effect of time and sleep.

Science.gov (United States)

Martin-Ordas, Gema; Call, Josep

2011-12-23

Following encoding, memory remains temporarily vulnerable to disruption. Consolidation refers to offline time-dependent processes that continue after encoding and stabilize, transform or enhance the memory trace. Memory consolidation resulting from sleep has been reported for declarative and non-declarative memories in humans. We first investigated the temporal course of memory retrieval in chimpanzees, bonobos and orangutans. We found that the amount of retrieved information was time dependent: apes' performance degraded after 1 and 2 h, stabilized after 4 h, started to increase after 8 and 12 h and fully recovered after 24 h. Second, we show that although memories during wakefulness were highly vulnerable to interference from events similar to those witnessed during the original encoding event, an intervening period of sleep not only stabilized apes' memories into more permanent ones but also protected them against interference.

Time, not sleep, unbinds contexts from item memory

NARCIS (Netherlands)

Cox, R.; Tijdens, R.R.; Meeter, M.; Sweegers, C.M.; Talamini, L.M.

2014-01-01

Contextual cues are known to benefit memory retrieval, but whether and how sleep affects this context effect remains unresolved. We manipulated contextual congruence during memory retrieval in human volunteers across 12 h and 24 h intervals beginning with either sleep or wakefulness. Our data

Sleep and rhythm changes at the time of Trypanosoma brucei invasion of the brain parenchyma in the rat.

Science.gov (United States)

Seke Etet, Paul F; Palomba, Maria; Colavito, Valeria; Grassi-Zucconi, Gigliola; Bentivoglio, Marina; Bertini, Giuseppe

2012-05-01

Human African trypanosomiasis (HAT), or sleeping sickness, is a severe disease caused by Trypanosoma brucei (T.b.). The disease hallmark is sleep alterations. Brain involvement in HAT is a crucial pathogenetic step for disease diagnosis and therapy. In this study, a rat model of African trypanosomiasis was used to assess changes of sleep-wake, rest-activity, and body temperature rhythms in the time window previously shown as crucial for brain parenchyma invasion by T.b. to determine potential biomarkers of this event. Chronic radiotelemetric monitoring in Sprague-Dawley rats was used to continuously record electroencephalogram, electromyogram, rest-activity, and body temperature in the same animals before (baseline recording) and after infection. Rats were infected with T.b. brucei. Data were acquired from 1 to 20 d after infection (parasite neuroinvasion initiates at 11-13 d post-infection in this model), and were compared to baseline values. Sleep parameters were manually scored from electroencephalographic-electromyographic tracings. Circadian rhythms of sleep time, slow-wave activity, rest-activity, and body temperature were studied using cosinor rhythmometry. Results revealed alterations of most of the analyzed parameters. In particular, sleep pattern and sleep-wake organization plus rest-activity and body temperature rhythms exhibited early quantitative and qualitative alterations, which became marked around the time interval crucial for parasite neuroinvasion or shortly after. Data derived from actigrams showed close correspondence with those from hypnograms, suggesting that rest-activity could be useful to monitor sleep-wake alterations in African trypanosomiasis.

Time to Work or Time to Play: The Effect of Student Employment on Homework, Housework, Screen Time, and Sleep

OpenAIRE

Sabrina Wulff Pabilonia; Charlene Marie Kalenkoski

2009-01-01

Recent research suggests that working while in high school reduces the amount of time students spend doing homework. However, an additional hour of work leads to a reduction in homework by much less than one hour, suggesting a reduction in other activities. This paper uses data from the 2003-2007 American Time Use Surveys (ATUS) to investigate the effects of market work on the time students spend on homework, sleeping, household work, and screen time. Results show that an increase in paid wor...

Sleep and Salivary Cortisol

DEFF Research Database (Denmark)

Garde, Anne Helene; Karlson, Bernt; Hansen, Åse Marie

2011-01-01

The aim of the present chapter was to analyze whether measures of cortisol in saliva were associated with measures of sleep and to explore if divergent results were related to underlying differences in theoretic assumptions and methods. Measures of sleep quality included sleep duration, overall...... sleep quality, difficulty falling asleep, disturbed sleep, and sleep deprivation. Twenty-three papers were found to fulfill the inclusion criteria. Cortisol measures were grouped into single time points at different times during the day, deviations at different time periods during the day, reactivity...... and recovery after a standardized laboratory test, area under the curve and response to dexamethasone test. A large proportion of the studies included showed non-significant findings, which, in several cases, may be a result of low power. The most consistent results were a positive association between sleep...

Sleep Insufficiency, Sleep Health Problems and Performance in High School Students

OpenAIRE

Ming, Xue; Koransky, Rebecca; Kang, Victor; Buchman, Sarah; Sarris, Christina E.; Wagner, George C.

2011-01-01

A survey on sleep schedule, sleep health, school performance and school start times was conducted in 1,941 adolescents. A high level of early and circadian-disadvantaged sleep/wake schedules during weekdays was observed. Shorter sleep duration on weekdays was reported, especially in upper classmen. Complaints of inadequate sleep and sleepiness during weekdays, alarm clock use, and napping were prevalent. Night awakening and prolonged sleep onset were common and associated with poor school per...

Time to improvement of pain and sleep quality in clinical trials of pregabalin for the treatment of fibromyalgia.

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Arnold, Lesley M; Emir, Birol; Pauer, Lynne; Resnick, Malca; Clair, Andrew

2015-01-01

To determine the time to immediate and sustained clinical improvement in pain and sleep quality with pregabalin in patients with fibromyalgia. A post hoc analysis of four 8- to 14-week phase 2-3, placebo-controlled trials of fixed-dose pregabalin (150-600 mg/day) for fibromyalgia, comprising 12 pregabalin and four placebo treatment arms. A total of 2,747 patients with fibromyalgia, aged 18-82 years. Pain and sleep quality scores, recorded daily on 11-point numeric rating scales (NRSs), were analyzed to determine time to immediate improvement with pregabalin, defined as the first of ≥2 consecutive days when the mean NRS score was significantly lower for pregabalin vs placebo in those treatment arms with a significant improvement at endpoint, and time to sustained clinical improvement with pregabalin, defined as a ≥1-point reduction of the baseline NRS score of patient responders who had a ≥30% improvement on the pain NRS, sleep NRS, or Fibromyalgia Impact Questionnaire (FIQ) from baseline to endpoint, or who reported "much improved" or "very much improved" on the Patient Global Impression of Change (PGIC) at endpoint. Significant improvements in pain and sleep quality scores at endpoint vs placebo were seen in 8/12 and 11/12 pregabalin treatment arms, respectively (P < 0.05). In these arms, time to immediate improvements in pain or sleep occurred by day 1 or 2. Time to sustained clinical improvement occurred significantly earlier in pain, sleep, PGIC, and FIQ responders (P < 0.02) with pregabalin vs placebo. Both immediate and sustained clinical improvements in pain and sleep quality occurred faster with pregabalin vs placebo. Wiley Periodicals, Inc.

Socio-Economic Status, Time Spending, and Sleep Duration in Indian Children and Adolescents

OpenAIRE

Bapat, Radhika; van Geel, Mitch; Vedder, Paul

2016-01-01

In this article physical activity, screen time, and academic work are studied as mediators between socio-economic status and sleep duration among school children in India. Participants were 268 school children aged 10?15 from Pune, India. They were sampled from private schools and impoverished public schools. We found that the highest socio-economic status children reported almost an hour and a half less sleep than their lowest socio-economic status counterparts. The lower socio-economic stat...

A Multispecies Approach to Co-Sleeping : Integrating Human-Animal Co-Sleeping Practices into Our Understanding of Human Sleep.

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Smith, Bradley P; Hazelton, Peta C; Thompson, Kirrilly R; Trigg, Joshua L; Etherton, Hayley C; Blunden, Sarah L

2017-09-01

Human sleeping arrangements have evolved over time and differ across cultures. The majority of adults share their bed at one time or another with a partner or child, and many also sleep with pets. In fact, around half of dog and cat owners report sharing a bed or bedroom with their pet(s). However, interspecies co-sleeping has been trivialized in the literature relative to interpersonal or human-human co-sleeping, receiving little attention from an interdisciplinary psychological perspective. In this paper, we provide a historical outline of the "civilizing process" that has led to current sociocultural conceptions of sleep as an individual, private function crucial for the functioning of society and the health of individuals. We identify similar historical processes at work in the formation of contemporary constructions of socially normative sleeping arrangements for humans and animals. Importantly, since previous examinations of co-sleeping practices have anthropocentrically framed this topic, the result is an incomplete understanding of co-sleeping practices. By using dogs as an exemplar of human-animal co-sleeping, and comparing human-canine sleeping with adult-child co-sleeping, we determine that both forms of co-sleeping share common factors for establishment and maintenance, and often result in similar benefits and drawbacks. We propose that human-animal and adult-child co-sleeping should be approached as legitimate and socially relevant forms of co-sleeping, and we recommend that co-sleeping be approached broadly as a social practice involving relations with humans and other animals. Because our proposition is speculative and derived from canine-centric data, we recommend ongoing theoretical refinement grounded in empirical research addressing co-sleeping between humans and multiple animal species.

Impact of Sleep Telemedicine Protocol in Management of Sleep Apnea: A 5-Year VA Experience.

Science.gov (United States)

Baig, Mirza M; Antonescu-Turcu, Andrea; Ratarasarn, Kavita

2016-05-01

There is growing evidence that demonstrates an important role for telemedicine technologies in enhancing healthcare delivery. A comprehensive sleep telemedicine protocol was implemented at the Veterans Administration Medical Center (VAMC), Milwaukee, WI, in 2008 in an effort to improve access to sleep specialty care. The telemedicine protocol relied heavily on sleep specialist interventions based on chart review (electronic consult [e-consult]). This was done in response to long wait time for sleep clinic visits as well as delayed sleep study appointments. Since 2008 all consults are screened by sleep service to determine the next step in intervention. Based on chart review, the following steps are undertaken: (1) eligibility for portable versus in-lab sleep study is determined, and a sleep study order is placed accordingly, (2) positive airway pressure (PAP) therapy is prescribed for confirmed sleep apnea, and (3) need for in-person evaluation in the sleep clinic is determined, and the visit is scheduled. This study summarizes the 5-year trend in various aspects of access to sleep care after implementation of sleep telemedicine protocol at the Milwaukee VAMC. This is a retrospective system efficiency study. The electronic medical record was interrogated 5 years after starting the sleep telemedicine protocol to study annual trends in the following outcomes: (1) interval between sleep consult and prescription of PAP equipment, (2) total sleep consults, and (3) sleep clinic wait time. Two part-time sleep physicians provided sleep-related care at the Milwaukee VAMC between 2008 and 2012. During this period, the interval between sleep consult and PAP prescription decreased from ≥60 days to ≤7 days. This occurred in spite of an increase in total sleep consults and sleep studies. There was also a significant increase in data downloads, indicating overall improved follow-up. There was no change in clinic wait time of ≥60 days. Implementation of a sleep telemedicine

Rapid Eye Movement Sleep, Sleep Continuity and Slow Wave Sleep as Predictors of Cognition, Mood, and Subjective Sleep Quality in Healthy Men and Women, Aged 20–84 Years

Directory of Open Access Journals (Sweden)

Ciro della Monica

2018-06-01

Full Text Available Sleep and its sub-states are assumed to be important for brain function across the lifespan but which aspects of sleep associate with various aspects of cognition, mood and self-reported sleep quality has not yet been established in detail. Sleep was quantified by polysomnography, quantitative Electroencephalogram (EEG analysis and self-report in 206 healthy men and women, aged 20–84 years, without sleep complaints. Waking brain function was quantified by five assessments scheduled across the day covering objectively assessed performance across cognitive domains including sustained attention and arousal, decision and response time, motor and sequence control, working memory, and executive function as well as self-reports of alertness, mood and affect. Controlled for age and sex, self-reported sleep quality was negatively associated with number of awakenings and positively associated with the duration of Rapid Eye Movement (REM sleep, but no significant associations with Slow Wave Sleep (SWS measures were observed. Controlling only for age showed that associations between objective and subjective sleep quality were much stronger in women than in men. Analysis of 51 performance measures demonstrated that, after controlling for age and sex, fewer awakenings and more REM sleep were associated significantly with better performance on the Goal Neglect task, which is a test of executive function. Factor analysis of the individual performance measures identified four latent variables labeled Mood/Arousal, Response Time, Accuracy, and Visual Perceptual Sensitivity. Whereas Mood/Arousal improved with age, Response Times became slower, while Accuracy and Visual perceptual sensitivity showed little change with age. After controlling for sex and age, nominally significant association between sleep and factor scores were observed such that Response Times were faster with more SWS, and Accuracy was reduced where individuals woke more often or had less REM

Feasibility and Emotional Impact of Experimentally Extending Sleep in Short-Sleeping Adolescents.

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Van Dyk, Tori R; Zhang, Nanhua; Catlin, Perry A; Cornist, Kaylin; McAlister, Shealan; Whitacre, Catharine; Beebe, Dean W

2017-09-01

Published experimental sleep manipulation protocols for adolescents have been limited to the summer, limiting causal conclusions about how short sleep affects them on school nights, when they are most likely to restrict their sleep. This study assesses the feasibility and emotional impact of a school-night sleep manipulation protocol to test the effects of lengthening sleep in habitually short-sleeping adolescents. High school students aged 14-18 years who habitually slept 5-7 hours on school nights participated in a 5-week experimental sleep manipulation protocol. Participants completed a baseline week followed in randomized counterbalanced order by two experimental conditions lasting 2 weeks each: prescribed habitual sleep (HAB; sleep time set to match baseline) and sleep extension (EXT; 1.5-hour increase in time in bed from HAB). All sleep was obtained at home, monitored with actigraphy. Data on adherence, protocol acceptability, mood and behavior were collected at the end of each condition. Seventy-six adolescents enrolled in the study, with 54 retained through all 5 weeks. Compared to HAB, during EXT, participants averaged an additional 72.6 minutes/night of sleep (p sleep manipulation protocol can be feasibly implemented which directly tests the potential protective effects of lengthening sleep. Many short-sleeping adolescents would benefit emotionally from sleeping longer, supporting public health efforts to promote adolescent sleep on school nights. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Delaying Middle School and High School Start Times Promotes Student Health and Performance: An American Academy of Sleep Medicine Position Statement.

Science.gov (United States)

Watson, Nathaniel F; Martin, Jennifer L; Wise, Merrill S; Carden, Kelly A; Kirsch, Douglas B; Kristo, David A; Malhotra, Raman K; Olson, Eric J; Ramar, Kannan; Rosen, Ilene M; Rowley, James A; Weaver, Terri E; Chervin, Ronald D

2017-04-15

During adolescence, internal circadian rhythms and biological sleep drive change to result in later sleep and wake times. As a result of these changes, early middle school and high school start times curtail sleep, hamper a student's preparedness to learn, negatively impact physical and mental health, and impair driving safety. Furthermore, a growing body of evidence shows that delaying school start times positively impacts student achievement, health, and safety. Public awareness of the hazards of early school start times and the benefits of later start times are largely unappreciated. As a result, the American Academy of Sleep Medicine is calling on communities, school boards, and educational institutions to implement start times of 8:30 AM or later for middle schools and high schools to ensure that every student arrives at school healthy, awake, alert, and ready to learn. © 2017 American Academy of Sleep Medicine

No Compromise of Competition Sleep Compared With Habitual Sleep in Elite Australian Footballers.

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Lalor, Benita J; Halson, Shona L; Tran, Jacqueline; Kemp, Justin G; Cormack, Stuart J

2018-01-01

To assess the impact of match-start time and days relative to match compared with the habitual sleep characteristics of elite Australian Football (AF) players. 45 elite male AF players were assessed during the preseason (habitual) and across 4 home matches during the season. Players wore an activity monitor the night before (-1), night of (0), 1 night after (+1), and 2 nights (+2) after each match and completed a self-reported rating of sleep quality. A 2-way ANOVA with Tukey post hoc was used to determine differences in sleep characteristics between match-start times and days relative to the match. Two-way nested ANOVA was conducted to examine differences between competition and habitual phases. Effect size ± 90% confidence interval (ES ± 90% CI) was calculated to quantify the magnitude of pairwise differences. Differences observed in sleep-onset latency (ES = 0.11 ± 0.16), sleep rating (ES = 0.08 ± 0.14), and sleep duration (ES = 0.08 ± 0.01) between competition and habitual periods were trivial. Sleep efficiency was almost certainly higher during competition than habitual, but this was not reflected in the subjective rating of sleep quality. Elite AF competition does not cause substantial disruption to sleep characteristics compared with habitual sleep. While match-start time has some impact on sleep variables, it appears that the match itself is more of a disruption than the start time. Subjective ratings of sleep from well-being questionnaires appear limited in their ability to accurately provide an indication of sleep quality.

Development of Home-Based Sleep Monitoring System for Obstructive Sleep Apnea.

Science.gov (United States)

Wu, Peirong; Chen, Guan-Ting; Cui, Yanyan; Li, Jin-Wei; Kuo, Terry B J; Chang, Polun

2017-01-01

Obstructive Sleep Apnea (OSA) has been proven to increase the risk of high blood pressure, heart attack, stroke, obesity, and diabetes. If people would like to know whether they are suffering from this sleep disorder, they need to go to particular hospital with which a sleep center that could perform polysomnography (PSG); however, for most people, this is not convenient. Consequently, the goal of this study is to develop a convenient, lower priced, and easy-to-use home-based sleep monitoring system. The researchers have developed the "Sleep Healthcare Management System" for OSA patients and healthcare providers. It combines smartphone and wearable devices that can perform real-time sleep monitoring. Healthcare providers could apply their professional knowledge to provide customized feedback via a web application. When the patient is diagnosed with an abnormal sleep health condition, healthcare providers may be able to provide appropriate and timely care.

Sleep alterations in mammals: did aquatic conditions inhibit rapid eye movement sleep?

Science.gov (United States)

Madan, Vibha; Jha, Sushil K

2012-12-01

Sleep has been studied widely in mammals and to some extent in other vertebrates. Higher vertebrates such as birds and mammals have evolved an inimitable rapid eye movement (REM) sleep state. During REM sleep, postural muscles become atonic and the temperature regulating machinery remains suspended. Although REM sleep is present in almost all the terrestrial mammals, the aquatic mammals have either radically reduced or completely eliminated REM sleep. Further, we found a significant negative correlation between REM sleep and the adaptation of the organism to live on land or in water. The amount of REM sleep is highest in terrestrial mammals, significantly reduced in semi-aquatic mammals and completely absent or negligible in aquatic mammals. The aquatic mammals are obligate swimmers and have to surface at regular intervals for air. Also, these animals live in thermally challenging environments, where the conductive heat loss is approximately ~90 times greater than air. Therefore, they have to be moving most of the time. As an adaptation, they have evolved unihemispheric sleep, during which they can rove as well as rest. A condition that immobilizes muscle activity and suspends the thermoregulatory machinery, as happens during REM sleep, is not suitable for these animals. It is possible that, in accord with Darwin's theory, aquatic mammals might have abolished REM sleep with time. In this review, we discuss the possibility of the intrinsic role of aquatic conditions in the elimination of REM sleep in the aquatic mammals.

Sleep Sleeping Patch

Institute of Scientific and Technical Information of China (English)

2008-01-01

The Sleep Sleeping Patch is a new kind of external patch based on modern sleep medicine research achievements, which uses the internationally advanced transdermal therapeutic system (TTS). The Sleep Sleeping Patch transmits natural sleep inducers such as peppermint and liquorice extracts and melatonin through the skin to induce sleep. Clinical research proves that the Sleep Sleeping Patch can effectively improve insomnia and the quality of sleep. Highly effective: With the modern TTS therapy,

Immediate postarousal sleep dynamics: an important determinant of sleep stability in obstructive sleep apnea.

Science.gov (United States)

Younes, Magdy; Hanly, Patrick J

2016-04-01

Arousability from sleep is increasingly recognized as an important determinant of the clinical spectrum of sleep disordered breathing (SDB). Patients with SDB display a wide range of arousability. The reason for these differences is not known. We hypothesized that differences in the speed with which sleep deepens following arousals/awakenings (postarousal sleep dynamics) is a major determinant of these differences in arousability in patients with SDB. We analyzed 40 preexisting clinical polysomnography records from patients with a range of SDB severity (apnea-hypopnea index 5-135/h). Sleep depth was determined every 3 s using the odds ratio product (ORP) method, a continuous index of sleep depth (0 = deep sleep, 2.5 = full wakefulness) that correlates strongly (r = 0.98) with arousability (Younes M, Ostrowski M, Soiferman M, Younes H, Younes M, Raneri J, and Hanly P. Sleep 38: 641-654, 2015). Time course of ORP was determined from end of arousal until the next arousal. All arousals were analyzed (142 ± 65/polysomnogram). ORP increased from 0.58 ± 0.32 during sleep to 1.67 ± 0.35 during arousals. ORP immediately (first 9 s) following arousals/awakenings (ORP-9) ranged from 0.21(very deep sleep) to 1.71 (highly arousable state) in different patients. In patients with high ORP-9, sleep deepened slowly (over minutes) beyond 9 s but only if no arousals/awakenings recurred. ORP-9 correlated strongly with average non-rapid eye movement sleep depth (r = 0.87, P sleep architecture. We conclude that postarousal sleep dynamics are highly variable among patients with sleep-disordered breathing and largely determine average sleep depth and continuity. Copyright © 2016 the American Physiological Society.

Sleep parameters, functional status and time post-stroke are associated with off-line motor skill learning in people with chronic stroke

Directory of Open Access Journals (Sweden)

Catherine eSiengsukon

2015-10-01

Full Text Available Background: Mounting evidence demonstrates that individuals with stroke benefit from sleep to enhance learning of a motor task. While stage NREM2 sleep and REM sleep have been associated with off-line motor skill learning in neurologically-intact individuals, it remains unknown which sleep parameters or specific sleep stages are associated with off-line motor skill learning in individuals with stroke. Methods: Twenty individuals with chronic stroke (> 6 months following stroke and 10 neurologically slept for three consecutive nights in a sleep laboratory with polysomnography. Participants practiced a tracking task the morning before the third night and underwent a retention test the morning following the third night. Off-line learning on the tracking task was assessed. Pearson’s correlations assessed for associations between the magnitude of off-line learning and sleep variables, age, upper extremity motor function, stroke severity, depression and time since stroke occurrence.Results: Individuals with stroke performed with significantly less error on the tracking task following a night of sleep (p=.006 while the control participants did not (p=.816. Increased sleep efficiency (r= -.285, less time spent in stage NREM3 sleep (r=.260, and more time spent in stage REM sleep (r= -.266 was weakly-to-moderately associated with increased magnitude of off-line motor learning. Furthermore, higher upper-extremity motor function (r = -.400, lower stroke severity (r = .360, and less time since stroke occurrence (r=.311 were moderately associated with increased magnitude of off-line motor learning. Conclusion: This study is the first study to provide insight into which sleep stages and individual characteristics may be associated with off-line learning in people with stroke. Future work should continue to understand which factors or combination of factors promote off-line motor learning in people with neurologic injury to best promote motor recovery in

Late Sleeping Affects Sleep Duration and Body Mass Index in Adolescents

Directory of Open Access Journals (Sweden)

Rajesh G.Kathrotia1,

2010-03-01

Full Text Available During adolescence, there is a tendency to sleep late andsleep less because of altered psychosocial and life-stylechanges. Recent studies have demonstrated the link betweensleeping less and gaining weight in children, adolescents, andadults. We studied the effect of late sleeping and sleepingless on body mass index (BMI in medical college freshmen.All participants were adolescents (104 male and 38 femaleadolescents, mean age 17.77±0.79 years. After obtaininginformed consent, they filled out a questionnaire about theirsleeping habits. Height and weight were measured after abrief history taking and clinical examination. BMI increasedsignificantly with decrease in total sleep duration and withdelayed bedtime. Late sleeping individuals (after midnighthad significantly less sleep duration (6.78 hours v 7.74 hours,P<0.001, more day time sleepiness (85.2% v 69.3%,P=0.033 and more gap between dinner time and going tosleep (234.16 min v 155.45 min, P<0.001. Increased BMI inlate sleepers may be explained by low physical activity duringthe day caused by excess sleepiness and increased calorieintake with a gap of 5-6 hours between dinner and sleep.Sleep habits of late sleeping and sleeping less contribute toincrease BMI in adolescents.

Sleep-related declarative memory consolidation and verbal replay during sleep talking in patients with REM sleep behavior disorder.

Directory of Open Access Journals (Sweden)

Ginevra Uguccioni

Full Text Available OBJECTIVE: To determine if sleep talkers with REM sleep behavior disorder (RBD would utter during REM sleep sentences learned before sleep, and to evaluate their verbal memory consolidation during sleep. METHODS: Eighteen patients with RBD and 10 controls performed two verbal memory tasks (16 words from the Free and Cued Selective Reminding Test and a 220-263 word long modified Story Recall Test in the evening, followed by nocturnal video-polysomnography and morning recall (night-time consolidation. In 9 patients with RBD, daytime consolidation (morning learning/recall, evening recall was also evaluated with the modified Story Recall Test in a cross-over order. Two RBD patients with dementia were studied separately. Sleep talking was recorded using video-polysomnography, and the utterances were compared to the studied texts by two external judges. RESULTS: Sleep-related verbal memory consolidation was maintained in patients with RBD (+24±36% words as in controls (+9±18%, p=0.3. The two demented patients with RBD also exhibited excellent nighttime consolidation. The post-sleep performance was unrelated to the sleep measures (including continuity, stages, fragmentation and apnea-hypopnea index. Daytime consolidation (-9±19% was worse than night-time consolidation (+29±45%, p=0.03 in the subgroup of 9 patients with RBD. Eleven patients with RBD spoke during REM sleep and pronounced a median of 20 words, which represented 0.0003% of sleep with spoken language. A single patient uttered a sentence that was judged to be semantically (but not literally related to the text learned before sleep. CONCLUSION: Verbal declarative memory normally consolidates during sleep in patients with RBD. The incorporation of learned material within REM sleep-associated sleep talking in one patient (unbeknownst to himself at the semantic level suggests a replay at a highly cognitive creative level.

Sleep in the Cape Mole Rat: A Short-Sleeping Subterranean Rodent.

Science.gov (United States)

Kruger, Jean-Leigh; Gravett, Nadine; Bhagwandin, Adhil; Bennett, Nigel C; Archer, Elizabeth K; Manger, Paul R

2016-01-01

The Cape mole rat Georychus capensis is a solitary subterranean rodent found in the western and southern Cape of South Africa. This approximately 200-gram bathyergid rodent shows a nocturnal circadian rhythm, but sleep in this species is yet to be investigated. Using telemetric recordings of the electroencephalogram (EEG) and electromyogram (EMG) in conjunction with video recordings, we were able to show that the Cape mole rat, like all other rodents, has sleep periods composed of both rapid eye movement (REM) and slow-wave (non-REM) sleep. These mole rats spent on average 15.4 h awake, 7.1 h in non-REM sleep and 1.5 h in REM sleep each day. Cape mole rats sleep substantially less than other similarly sized terrestrial rodents but have a similar percentage of total sleep time occupied by REM sleep. In addition, the duration of both non-REM and REM sleep episodes was markedly shorter in the Cape mole rat than has been observed in terrestrial rodents. Interestingly, these features (total sleep time and episode duration) are similar to those observed in another subterranean bathyergid mole rat, i.e. Fukomys mechowii. Thus, there appears to be a bathyergid type of sleep amongst the rodents that may be related to their environment and the effect of this on their circadian rhythm. Investigating further species of bathyergid mole rats may fully define the emerging picture of sleep in these subterranean African rodents. © 2016 S. Karger AG, Basel.

[Sleep habits, sleep quality and sleep medicine use of the Swiss population result].

Science.gov (United States)

Tinguely, Gilberte; Landolt, Hans-Peter; Cajochen, Christian

2014-11-01

A survey in a representative sample of the Swiss population revealed an average sleep duration of 7.5 hours on workdays and of 8.5 hours on free days, which reflected a more than half an hour (38 min) shorter sleep duration than 28 years ago. The mean time in bed was between 22:41 and 06:37 on workdays and between 23:29 and 08:27 on free days. On workdays as well as on free days the bedtime was delayed by 47 minutes in comparison to a similar survey 28 years ago. By contrast, the mean rise times on workdays and free days did not change. The sleep duration required to feel refreshed was indicated with 7 hours, which was 41 minutes less than 28 years ago. Roughly 90 % of the interviewees answered that they felt healthy, and 75 % described their sleep as good or very good compared to 79 % 28 years ago. The most frequent reasons stated for bad sleep were personal problems and strain at the workplace. The effect of bad quality sleep on every day functioning was considered as essential by 65 % of the respondents compared to 69 % 28 years ago. The use of medication to improve sleep was declared by 2.8 % (2.7 % 28 years ago), most often benzodiazepines, but also Valerian products and so-called z-drugs. In comparison with similar surveys in other countries (France, Great Britain and USA), Swiss residents slept roughly half an hour longer, but these other countries alike showed a sizable shortening of their habitual sleep duration over the last decades.

A quasi-experimental study of the impact of school start time changes on adolescent sleep.

Science.gov (United States)

Owens, Judith A; Dearth-Wesley, Tracy; Herman, Allison N; Oakes, J Michael; Whitaker, Robert C

2017-12-01

To determine whether simultaneous school start time changes (delay for some schools; advance for others) impact adolescents' sleep. Quasi-experimental study using cross-sectional surveys before and after changes to school start times in September 2015. Eight middle (grades 7-8), 3 secondary (grades 7-12), and 8 high (grades 9-12) schools in Fairfax County (Virginia) public schools. A total of 2017 (6% of ~34,900) students were surveyed before start time changes, and 1180 (3% of ~35,300) were surveyed after. A 50-minute delay (7:20 to 8:10 am) in start time for high schools and secondary schools and a 30-minute advance (8:00 to 7:30 am) for middle schools. Differences before and after start time changes in self-reported sleep duration and daytime sleepiness. Among respondents, 57.5% were non-Hispanic white, and 10.3% received free or reduced-priced school meals. Before start time changes, high/secondary and middle school students slept a mean (SD) of 7.4 (1.2) and 8.4 (1.0) hours on school nights, respectively, and had a prevalence of daytime sleepiness of 78.4% and 57.2%, respectively. Adjusted for potential confounders, students with a 50-minute delay slept 30.1 minutes longer (95% confidence interval [CI], 24.3-36.0) on school nights and had less daytime sleepiness (-4.8%; 95% CI, -8.5% to -1.1%), whereas students with a 30-minute advance slept 14.8 minutes less (95% CI, -21.6 to -8.0) and had more daytime sleepiness (8.0%; 95% CI, 2.5%-13.5%). Both advances and delays in school start times are associated with changes in adolescents' school-night sleep duration and daytime sleepiness. Larger changes might occur with later start times. Copyright © 2017 National Sleep Foundation. Published by Elsevier Inc. All rights reserved.

REM Sleep Phase Preference in the Crepuscular Octodon degus Assessed by Selective REM Sleep Deprivation

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Ocampo-Garcés, Adrián; Hernández, Felipe; Palacios, Adrian G.

2013-01-01

Study Objectives: To determine rapid eye movement (REM) sleep phase preference in a crepuscular mammal (Octodon degus) by challenging the specific REM sleep homeostatic response during the diurnal and nocturnal anticrepuscular rest phases. Design: We have investigated REM sleep rebound, recovery, and documented REM sleep propensity measures during and after diurnal and nocturnal selective REM sleep deprivations. Subjects: Nine male wild-captured O. degus prepared for polysomnographic recordings Interventions: Animals were recorded during four consecutive baseline and two separate diurnal or nocturnal deprivation days, under a 12:12 light-dark schedule. Three-h selective REM sleep deprivations were performed, starting at midday (zeitgeber time 6) or midnight (zeitgeber time 18). Measurements and Results: Diurnal and nocturnal REM sleep deprivations provoked equivalent amounts of REM sleep debt, but a consistent REM sleep rebound was found only after nocturnal deprivation. The nocturnal rebound was characterized by a complete recovery of REM sleep associated with an augment in REM/total sleep time ratio and enhancement in REM sleep episode consolidation. Conclusions: Our results support the notion that the circadian system actively promotes REM sleep. We propose that the sleep-wake cycle of O. degus is modulated by a chorus of circadian oscillators with a bimodal crepuscular modulation of arousal and a unimodal promotion of nocturnal REM sleep. Citation: Ocampo-Garcés A; Hernández F; Palacios AG. REM sleep phase preference in the crepuscular Octodon degus assessed by selective REM sleep deprivation. SLEEP 2013;36(8):1247-1256. PMID:23904685

Sleep-wake patterns and sleep disturbance among Hong Kong Chinese adolescents.

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Chung, Ka-Fai; Cheung, Miao-Miao

2008-02-01

To determine sleep-wake patterns and evaluate sleep disturbance in Hong Kong adolescents; to identify factors that are associated with sleep disturbance; and to examine the relationship of sleep-wake variables and academic performance. A school-based cross-sectional survey. Sample included 1629 adolescents aged 12 to 19 years. Self-report questionnaires, including sleep-wake habit questionnaire, Sleep Quality Index, Morningness/ Eveningness scale, Epworth Sleepiness Scale, Perceived Stress Scale, academic performance, and personal data were administered. The average school-night bedtime was 23:24, and total sleep time was 7.3 hr. During weekends, the average bedtime and rise time was delayed by 64 min and 195 min, respectively. The prevalence of sleep disturbances occurring > or = 3 days per week in the preceding 3 months were: difficulty falling asleep (5.6%), waking up during the night (7.2%), and waking up too early in the morning (10.4%). The prevalence of > or = 1 of these three symptoms was 19.1%. Stepwise regression analyses revealed that circadian phase preference was the most significant predictor for school night bedtime, weekend oversleep, and daytime sleepiness. Perceived stress was the most significant risk factor for sleep disturbance. Students with marginal academic performance reported later bedtimes and shorter sleep during school nights, greater weekend delays in bedtime, and more daytime sleepiness than those with better grades. The prevalence of sleep deprivation and sleep disturbance among Hong Kong adolescents is comparable to those found in other countries. An intervention program for sleep problems in adolescents should be considered.

Impact of sleep duration on seizure frequency in adults with epilepsy: a sleep diary study.

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Cobabe, Maurine M; Sessler, Daniel I; Nowacki, Amy S; O'Rourke, Colin; Andrews, Noah; Foldvary-Schaefer, Nancy

2015-02-01

Prolonged sleep deprivation activates epileptiform EEG abnormalities and seizures in people with epilepsy. Few studies have addressed the effect of chronic partial sleep deprivation on seizure occurrence in populations with epilepsy. We tested the primary hypothesis that partial sleep deprivation over 24- and 72-hour periods increases seizure occurrence in adults with epilepsy. Forty-four subjects completed a series of self-reported instruments, as well as 1-month sleep and seizure diaries, to characterize their sleep and quality of life. Diaries were used to determine the relationship between seizure occurrence and total sleep time 24 and 72h before seizure occurrence using random effects models and a logistic regression model fit by generalized estimating equations. A total of 237 seizures were recorded during 1295 diary days, representing 5.5±7.0 (mean±SD) seizures per month. Random effects models for 24- and 72-hour total sleep times showed no clinically or statistically significant differences in the total sleep time between preseizure periods and seizure-free periods. The average 24-hour total sleep time during preseizure 24-hour periods was 8min shorter than that during seizure-free periods (p=0.51). The average 72-hour total sleep time during preseizure periods was 20min longer than that during seizure-free periods (p=0.86). The presence of triggers was a significant predictor of seizure occurrence, with stress/anxiety noted most often as a trigger. Mean total sleep time was 9h, and subjects took an average of 12±10 naps per month, having a mean duration of 1.9±1.2h. Daytime sleepiness, fatigue, and insomnia symptoms were commonly reported. Small degrees of sleep loss were not associated with seizure occurrence in our sample of adults with epilepsy. Our results also include valuable observations of the altered sleep times and frequent napping habits of adults with refractory epilepsy and the potential contribution of these habits to quality of life and

Sleep During Pregnancy: The nuMoM2b Pregnancy and Sleep Duration and Continuity Study.

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Reid, Kathryn J; Facco, Francesca L; Grobman, William A; Parker, Corette B; Herbas, Marcos; Hunter, Shannon; Silver, Robert M; Basner, Robert C; Saade, George R; Pien, Grace W; Manchanda, Shalini; Louis, Judette M; Nhan-Chang, Chia-Lang; Chung, Judith H; Wing, Deborah A; Simhan, Hyagriv N; Haas, David M; Iams, Jay; Parry, Samuel; Zee, Phyllis C

2017-05-01

To characterize sleep duration, timing and continuity measures in pregnancy and their association with key demographic variables. Multisite prospective cohort study. Women enrolled in the nuMoM2b study (nulliparous women with a singleton gestation) were recruited at the second study visit (16-21 weeks of gestation) to participate in the Sleep Duration and Continuity substudy. Women sleep log for 7 consecutive days. Time in bed, sleep duration, fragmentation index, sleep efficiency, wake after sleep onset, and sleep midpoint were averaged across valid primary sleep periods for each participant. Valid data were available from 782 women with mean age of 27.3 (5.5) years. Median sleep duration was 7.4 hours. Approximately 27.9% of women had a sleep duration of sleep duration of >9 hours. In multivariable models including age, race/ethnicity, body mass index, insurance status, and recent smoking history, sleep duration was significantly associated with race/ethnicity and insurance status, while time in bed was only associated with insurance status. Sleep continuity measures and sleep midpoint were significantly associated with all covariates in the model, with the exception of age for fragmentation index and smoking for wake after sleep onset. Our results demonstrate the relationship between sleep and important demographic characteristics during pregnancy. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Initial Sleep Time Predicts Success in Manual-Guided Cognitive Behavioral Therapy for Insomnia.

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Bothelius, Kristoffer; Kyhle, Kicki; Broman, Jan-Erik; Gordh, Torsten; Fredrikson, Mats

2016-01-01

Cognitive behavioral therapy produces significant and long-lasting improvement for individuals with insomnia, but treatment resources are scarce. A "stepped care" approach has therefore been proposed, but knowledge is limited on how to best allocate patients to different treatment steps. In this study, 66 primary-care patients with insomnia attended a low-end treatment step: manual-guided cognitive behavioral therapy (CBT) for insomnia delivered by ordinary primary-care personnel. Based on clinically significant treatment effects, subjects were grouped into treatment responders or nonresponders. Baseline data were analyzed to identify predictors for treatment success. Long total sleep time at baseline assessment was the only statistically significant predictor for becoming a responder, and sleep time may thus be important to consider before enrolling patients in low-end treatments.

Sleep, Recovery, and Performance in Sports.

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Malhotra, Raman K

2017-08-01

Poor sleep can lead to decreases in performance and recovery for athletes. Sleep disorders and symptoms are commonly seen in athletes, and may be unrecognized. It is important to educate athletes on adequate duration, quality, and timing of sleep. Interventions may include changes to practice times or careful planning for travel to games in different time zones. It is important to screen and treat sleep disorders such as sleep apnea and insomnia that are seen in some athletes. In patients who suffer concussion, it is important to address sleep issues, as poor sleep can prolong or exacerbate other concussion symptoms. Copyright © 2017 Elsevier Inc. All rights reserved.

How Many Sleep Diary Entries Are Needed to Reliably Estimate Adolescent Sleep?

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Arora, Teresa; Gradisar, Michael; Taheri, Shahrad; Carskadon, Mary A.

2017-01-01

Abstract Study Objectives: To investigate (1) how many nights of sleep diary entries are required for reliable estimates of five sleep-related outcomes (bedtime, wake time, sleep onset latency [SOL], sleep duration, and wake after sleep onset [WASO]) and (2) the test–retest reliability of sleep diary estimates of school night sleep across 12 weeks. Methods: Data were drawn from four adolescent samples (Australia [n = 385], Qatar [n = 245], United Kingdom [n = 770], and United States [n = 366]), who provided 1766 eligible sleep diary weeks for reliability analyses. We performed reliability analyses for each cohort using complete data (7 days), one to five school nights, and one to two weekend nights. We also performed test–retest reliability analyses on 12-week sleep diary data available from a subgroup of 55 US adolescents. Results: Intraclass correlation coefficients for bedtime, SOL, and sleep duration indicated good-to-excellent reliability from five weekday nights of sleep diary entries across all adolescent cohorts. Four school nights was sufficient for wake times in the Australian and UK samples, but not the US or Qatari samples. Only Australian adolescents showed good reliability for two weekend nights of bedtime reports; estimates of SOL were adequate for UK adolescents based on two weekend nights. WASO was not reliably estimated using 1 week of sleep diaries. We observed excellent test–rest reliability across 12 weeks of sleep diary data in a subsample of US adolescents. Conclusion: We recommend at least five weekday nights of sleep dairy entries to be made when studying adolescent bedtimes, SOL, and sleep duration. Adolescent sleep patterns were stable across 12 consecutive school weeks. PMID:28199718

Association of sleep and academic performance.

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Eliasson, Arne; Eliasson, Anders; King, Joseph; Gould, Ben; Eliasson, Arn

2002-03-01

Poor school performance by adolescent students has been attributed in part to insufficient sleep. It is recognized that a number of factors lead to diminished total sleep time and chief among these are early school start times and sleep phase delay in adolescence. Political initiatives are gaining momentum across the United States to require later school start times with the intent of increasing total sleep time and consequently improving school performance. Later school start times come with significant costs and impact other activities of families and communities. The decision to implement later school start times cannot be made lightly and deserves support of well-performed research on the impact of these changes. A study evaluating the association of academic performance and total sleep time was performed in middle school and high school students in a suburban Maryland school system. Preliminary results of this study show no correlation of total sleep time with academic performance. Before mandating costly changes in school schedules, it would be useful to perform further research to determine the effects of increasing sleep time on the behaviors of adolescent students.

Solving the mystery of human sleep schedules one mutation at a time.

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Hallows, William C; Ptáček, Louis J; Fu, Ying-Hui

2013-01-01

Sleep behavior remains one of the most enigmatic areas of life. The unanswered questions range from "why do we sleep?" to "how we can improve sleep in today's society?" Identification of mutations responsible for altered circadian regulation of human sleep lead to unique opportunities for probing these territories. In this review, we summarize causative circadian mutations found from familial genetic studies to date. We also describe how these mutations mechanistically affect circadian function and lead to altered sleep behaviors, including shifted or shortening of sleep patterns. In addition, we discuss how the investigation of mutations can not only expand our understanding of the molecular mechanisms regulating the circadian clock and sleep duration, but also bridge the pathways between clock/sleep and other human physiological conditions and ailments such as metabolic regulation and migraine headaches.

Adolescent sleep patterns and night-time technology use: results of the Australian Broadcasting Corporation's Big Sleep Survey.

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Amanda L Gamble

Full Text Available INTRODUCTION: Electronic devices in the bedroom are broadly linked with poor sleep in adolescents. This study investigated whether there is a dose-response relationship between use of electronic devices (computers, cellphones, televisions and radios in bed prior to sleep and adolescent sleep patterns. METHODS: Adolescents aged 11-17 yrs (n = 1,184; 67.6% female completed an Australia-wide internet survey that examined sleep patterns, sleepiness, sleep disorders, the presence of electronic devices in the bedroom and frequency of use in bed at night. RESULTS: Over 70% of adolescents reported 2 or more electronic devices in their bedroom at night. Use of devices in bed a few nights per week or more was 46.8% cellphone, 38.5% computer, 23.2% TV, and 15.8% radio. Device use had dose-dependent associations with later sleep onset on weekdays (highest-dose computer adjOR  = 3.75: 99% CI  = 2.17-6.46; cellphone 2.29: 1.22-4.30 and weekends (computer 3.68: 2.14-6.32; cellphone 3.24: 1.70-6.19; TV 2.32: 1.30-4.14, and later waking on weekdays (computer 2.08: 1.25-3.44; TV 2.31: 1.33-4.02 and weekends (computer 1.99: 1.21-3.26; cellphone 2.33: 1.33-4.08; TV 2.04: 1.18-3.55. Only 'almost every night' computer use (: 2.43: 1.45-4.08 was associated with short weekday sleep duration, and only 'almost every night' cellphone use (2.23: 1.26-3.94 was associated with wake lag (waking later on weekends. CONCLUSIONS: Use of computers, cell-phones and televisions at higher doses was associated with delayed sleep/wake schedules and wake lag, potentially impairing health and educational outcomes.

The Effects of Sleep Extension on Sleep, Performance, Immunity and Physical Stress in Rugby Players.

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Swinbourne, Richard; Miller, Joanna; Smart, Daniel; Dulson, Deborah K; Gill, Nicholas

2018-05-10

(1) Background: The purpose of the present study was to examine the efficacy of sleep extension in professional rugby players. The aims were to: (i) characterise sleep quantity in elite rugby players and determine changes in immune function and stress hormone secretion during a pre-season training programme; (ii) evaluate the efficacy of a sleep extension intervention in improving sleep, markers of physical stress, immune function and performance. (2) Methods: Twenty five highly trained athletes from a professional rugby team (age (mean ± SD) 25 ± 2.7 years; height 1.87 ± 0.07 m; weight 105 ± 12.1 kg) participated in a six week pre-post control-trial intervention study. Variables of sleep, immune function, sympathetic nervous activity, physiological stress and reaction times were measured. (3) Results: Sleep extension resulted in a moderate improvement in sleep quality scores ([mean; ± 90% confidence limits] −24.8%; ± 54.1%) and small to moderate increases in total sleep time (6.3%; ± 6.3%) and time in bed (7.3%; ± 3.6%). In addition, a small decrease in cortisol (−18.7%; ± 26.4%) and mean reaction times (−4.3%; ± 3.1%) was observed following the intervention, compared to the control. (4) Conclusions: Professional rugby players are at risk of poor sleep during pre-season training, with concomitant rises in physical stress. Implementing a sleep extension programme among professional athletes is recommended to improve sleep, with beneficial changes in stress hormone expression and reaction time performance.

The Effects of Sleep Extension on Sleep, Performance, Immunity and Physical Stress in Rugby Players

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Richard Swinbourne

2018-05-01

Full Text Available (1 Background: The purpose of the present study was to examine the efficacy of sleep extension in professional rugby players. The aims were to: (i characterise sleep quantity in elite rugby players and determine changes in immune function and stress hormone secretion during a pre-season training programme; (ii evaluate the efficacy of a sleep extension intervention in improving sleep, markers of physical stress, immune function and performance. (2 Methods: Twenty five highly trained athletes from a professional rugby team (age (mean ± SD 25 ± 2.7 years; height 1.87 ± 0.07 m; weight 105 ± 12.1 kg participated in a six week pre-post control-trial intervention study. Variables of sleep, immune function, sympathetic nervous activity, physiological stress and reaction times were measured. (3 Results: Sleep extension resulted in a moderate improvement in sleep quality scores ([mean; ± 90% confidence limits] −24.8%; ± 54.1% and small to moderate increases in total sleep time (6.3%; ± 6.3% and time in bed (7.3%; ± 3.6%. In addition, a small decrease in cortisol (−18.7%; ± 26.4% and mean reaction times (−4.3%; ± 3.1% was observed following the intervention, compared to the control. (4 Conclusions: Professional rugby players are at risk of poor sleep during pre-season training, with concomitant rises in physical stress. Implementing a sleep extension programme among professional athletes is recommended to improve sleep, with beneficial changes in stress hormone expression and reaction time performance.

The great sleep recession: changes in sleep duration among US adolescents, 1991-2012.

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Keyes, Katherine M; Maslowsky, Julie; Hamilton, Ava; Schulenberg, John

2015-03-01

Average nightly sleep times precipitously decline from childhood through adolescence. There is increasing concern that historical shifts also occur in overall adolescent sleep time. Data were drawn from Monitoring the Future, a yearly, nationally representative cross-sectional survey of adolescents in the United States from 1991 to 2012 (N = 272 077) representing birth cohorts from 1973 to 2000. Adolescents were asked how often they get ≥7 hours of sleep and how often they get less sleep than they should. Age-period-cohort models were estimated. Adolescent sleep generally declined over 20 years; the largest change occurred between 1991-1995 and 1996-2000. Age-period-cohort analyses indicate adolescent sleep is best described across demographic subgroups by an age effect, with sleep decreasing across adolescence, and a period effect, indicating that sleep is consistently decreasing, especially in the late 1990s and early 2000s. There was also a cohort effect among some subgroups, including male subjects, white subjects, and those in urban areas, with the earliest cohorts obtaining more sleep. Girls were less likely to report getting ≥7 hours of sleep compared with boys, as were racial/ethnic minorities, students living in urban areas, and those of low socioeconomic status (SES). However, racial/ethnic minorities and adolescents of low SES were more likely to self-report adequate sleep, compared with white subjects and those of higher SES. Declines in self-reported adolescent sleep across the last 20 years are concerning. Mismatch between perceptions of adequate sleep and actual reported sleep times for racial/ethnic minorities and adolescents of low SES are additionally concerning and suggest that health education and literacy approaches may be warranted. Copyright © 2015 by the American Academy of Pediatrics.

Sleep in childhood and adolescence: age-specific sleep characteristics, common sleep disturbances and associated difficulties.

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Barclay, Nicola L; Gregory, Alice M

2014-01-01

Sleep changes throughout the lifespan, with particularly salient alterations occurring during the first few years of life, as well as during the transition from childhood to adolescence. Such changes are partly the result of brain maturation; complex changes in the organisation of the circadian system; as well as changes in daily routine, environmental demands and responsibilities. Despite the automaticity of sleep, given that it is governed by a host of complex mechanisms, there are times when sleep becomes disturbed. Sleep disturbances in childhood are common and may stem from behavioural difficulties or abnormalities in physiological processes-and, in some cases manifest into diagnosable sleep disorders. As well as occurring exclusively, childhood sleep disturbances often co-occur with other difficulties. The purpose of this chapter is to outline the neurobiology of typical sleep/wake processes, and describe changes in sleep physiology and architecture from birth to adulthood. Furthermore, common childhood sleep disorders are described as are their associations with other traits, including all of the syndromes presented in this handbook: ASDs, ADHD, schizophrenia and emotional/behavioural difficulties. Throughout, we attempt to explain possible mechanisms underlying these disorders and their associations.

"I Have to Rest All the Time Because You Are Not Allowed to Play": Exploring Children's Perceptions of Autonomy during Sleep-Time in Long Day Care Services

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Nothard, Michaela; Irvine, Susan; Theobald, Maryanne; Staton, Sally; Pattinson, Cassandra; Thorpe, Karen

2015-01-01

Daytime sleep is a significant part of the daily routine for children attending early childhood education and care (ECEC) services in Australia and many other countries. The practice of sleep-time can account for a substantial portion of the day in ECEC and often involves a mandated sleep/rest period for all children, including older…

Sleep inertia, sleep homeostatic and circadian influences on higher-order cognitive functions.

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Burke, Tina M; Scheer, Frank A J L; Ronda, Joseph M; Czeisler, Charles A; Wright, Kenneth P

2015-08-01

Sleep inertia, sleep homeostatic and circadian processes modulate cognition, including reaction time, memory, mood and alertness. How these processes influence higher-order cognitive functions is not well known. Six participants completed a 73-day-long study that included two 14-day-long 28-h forced desynchrony protocols to examine separate and interacting influences of sleep inertia, sleep homeostasis and circadian phase on higher-order cognitive functions of inhibitory control and selective visual attention. Cognitive performance for most measures was impaired immediately after scheduled awakening and improved during the first ~2-4 h of wakefulness (decreasing sleep inertia); worsened thereafter until scheduled bedtime (increasing sleep homeostasis); and was worst at ~60° and best at ~240° (circadian modulation, with worst and best phases corresponding to ~09:00 and ~21:00 hours, respectively, in individuals with a habitual wake time of 07:00 hours). The relative influences of sleep inertia, sleep homeostasis and circadian phase depended on the specific higher-order cognitive function task examined. Inhibitory control appeared to be modulated most strongly by circadian phase, whereas selective visual attention for a spatial-configuration search task was modulated most strongly by sleep inertia. These findings demonstrate that some higher-order cognitive processes are differentially sensitive to different sleep-wake regulatory processes. Differential modulation of cognitive functions by different sleep-wake regulatory processes has important implications for understanding mechanisms contributing to performance impairments during adverse circadian phases, sleep deprivation and/or upon awakening from sleep. © 2015 European Sleep Research Society.

Sleep education in college: a preliminary study.

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Tsai, Ling-Ling; Li, Sheng-Ping

2004-12-01

In this study we evaluated the effect of a two-credit (100 min./week) "Sleep Management" course on the sleep patterns of college students as the course progressed over an 18-wk. semester. Curricular activity included lectures, group discussions, and practice of self-evaluation of sleep. Instead of giving the students the whole list of sleep hygiene at the outset of the course, each concept of sleep hygiene was introduced and discussed under related lecture topics. A total of 241 students (131 men and 110 women) took the course and kept 7-day sleep logs three times. Concurrently, sleep-log data were collected from 65 students (32 men and 33 women) who were not taking the course. Both groups showed similar varieties of academic backgrounds and characteristics of sleep patterns at the beginning. Similarly, their sleep patterns, namely, rise time, nighttime awakenings, time asleep, time in bed, sleep efficiency, and rise time regularity, changed over the semester. Women in both groups had more nighttime awakenings. In contrast, sleep quality was progressively better for the group in the course but not for the control group. Only women in the course decreased their nap time in the second and third months. Thus, the course of "Sleep Management" only had a mild and limited effect on sleep patterns. The course content needs refinement to maximize influence on students' sleep patterns and habits, particularly, on reduction of insufficient sleep and daytime sleepiness which are the highest ranking sleep problems among college students.

Repeated sleep restriction in rats leads to homeostatic and allostatic responses during recovery sleep.

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Kim, Youngsoo; Laposky, Aaron D; Bergmann, Bernard M; Turek, Fred W

2007-06-19

Recent studies indicate that chronic sleep restriction can have negative consequences for brain function and peripheral physiology and can contribute to the allostatic load throughout the body. Interestingly, few studies have examined how the sleep-wake system itself responds to repeated sleep restriction. In this study, rats were subjected to a sleep-restriction protocol consisting of 20 h of sleep deprivation (SD) followed by a 4-h sleep opportunity each day for 5 consecutive days. In response to the first 20-h SD block on day 1, animals responded during the 4-h sleep opportunity with enhanced sleep intensity [i.e., nonrapid eye movement (NREM) delta power] and increased rapid eye movement sleep time compared with baseline. This sleep pattern is indicative of a homeostatic response to acute sleep loss. Remarkably, after the 20-h SD blocks on days 2-5, animals failed to exhibit a compensatory NREM delta power response during the 4-h sleep opportunities and failed to increase NREM and rapid eye movement sleep times, despite accumulating a sleep debt each consecutive day. After losing approximately 35 h of sleep over 5 days of sleep restriction, animals regained virtually none of their lost sleep, even during a full 3-day recovery period. These data demonstrate that the compensatory/homeostatic sleep response to acute SD does not generalize to conditions of chronic partial sleep loss. We propose that the change in sleep-wake regulation in the context of repeated sleep restriction reflects an allostatic process, and that the allostatic load produced by SD has direct effects on the sleep-wake regulatory system.

Chronic Stress is Prospectively Associated with Sleep in Midlife Women: The SWAN Sleep Study.

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Hall, Martica H; Casement, Melynda D; Troxel, Wendy M; Matthews, Karen A; Bromberger, Joyce T; Kravitz, Howard M; Krafty, Robert T; Buysse, Daniel J

2015-10-01

Evaluate whether levels of upsetting life events measured over a 9-y period prospectively predict subjective and objective sleep outcomes in midlife women. Prospective cohort study. Four sites across the United States. 330 women (46-57 y of age) enrolled in the Study of Women's Health Across the Nation (SWAN) Sleep Study. N/A. Upsetting life events were assessed annually for up to 9 y. Trajectory analysis applied to life events data quantitatively identified three distinct chronic stress groups: low stress, moderate stress, and high stress. Sleep was assessed by self-report and in-home polysomnography (PSG) during the ninth year of the study. Multivariate analyses tested the prospective association between chronic stress group and sleep, adjusting for race, baseline sleep complaints, marital status, body mass index, symptoms of depression, and acute life events at the time of the Sleep Study. Women characterized by high chronic stress had lower subjective sleep quality, were more likely to report insomnia, and exhibited increased PSG-assessed wake after sleep onset (WASO) relative to women with low to moderate chronic stress profiles. The effect of chronic stress group on WASO persisted in the subsample of participants without baseline sleep complaints. Chronic stress is prospectively associated with sleep disturbance in midlife women, even after adjusting for acute stressors at the time of the sleep study and other factors known to disrupt sleep. These results are consistent with current models of stress that emphasize the cumulative effect of stressors on health over time. © 2015 Associated Professional Sleep Societies, LLC.

Pinellia ternata (Thunb.) Makino Preparation promotes sleep by increasing REM sleep.

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Lin, Sisi; Nie, Bo; Yao, Guihong; Yang, Hui; Ye, Ren; Yuan, Zhengzhong

2018-05-15

Pinellia ternata (Thunb.) Makino Preparation (PTP) is widely used to treat insomnia in traditional Chinese medicine; however, its specific role is not clear. In this study, PTP was prepared at three concentrations. For locomotor activity tests, mice were treated with PTP and evaluated for 14 days. For polygraph recordings, mice were treated for 14 days and recorded after treatment. The main chemical constituents in PTP were identified by Ultra performance liquid chromatography/quadrupole time spectrometry (UPLC/Q-TOF-MS). The results showed that 0.9 g/mL PTP significantly reduced locomotor activity. The effect was related to the time of treatment. PTP reduced wakefulness and increased sleep in mice. Furthermore, PTP promoted sleep by increasing the number of REM sleep episodes with a duration of 64-128s and increasing the number of transitions from NREM sleep to REM sleep and from REM sleep to wakefulness. A total of 17 compounds were identified.

Does the duration and time of sleep increase the risk of allergic rhinitis? Results of the 6-year nationwide Korea youth risk behavior web-based survey.

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Jeoung A Kwon

Full Text Available Allergic rhinitis (AR is the most common chronic disorder in the pediatric population. Although several studies have investigated the correlation between AR and sleep-related issues, the association between the duration and time of sleep and AR has not been analyzed in long-term national data. This study investigated the relationship between sleep time and duration and AR risk in middle- and high-school students (adolescents aged 12-18. We analyzed national data from the Korea Youth Risk Behavior Web-based Survey by the Korea Centers for Disease Control and Prevention from 2007-2012. The sample size was 274,480, with an average response rate of 96.2%. Multivariate logistic regression analyses were conducted to determine the relationship between sleep and AR risk. Furthermore, to determine the best-fitted model among independent variables such as sleep duration, sleep time, and the combination of sleep duration and sleep time, we used Akaike Information Criteria (AIC to compare models. A total of 43,337 boys and 41,665 girls reported a diagnosis of AR at baseline. The odds ratio increased with age and with higher education and economic status of the parents. Further, students in mid-sized and large cities had stronger relationships to AR than those in small cities. In both genders, AR was associated with depression and suicidal ideation. In the analysis of sleep duration and sleep time, the odds ratio increased in both genders when sleep duration was <7 hours, and when the time of sleep was later than 24:00 hours. Our results indicate an association between sleep time and duration and AR. This study is the first to focus on the relationship between sleep duration and time and AR in national survey data collected over 6 years.

Daily rhythms of the sleep-wake cycle

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Waterhouse Jim

2012-03-01

Full Text Available Abstract The amount and timing of sleep and sleep architecture (sleep stages are determined by several factors, important among which are the environment, circadian rhythms and time awake. Separating the roles played by these factors requires specific protocols, including the constant routine and altered sleep-wake schedules. Results from such protocols have led to the discovery of the factors that determine the amounts and distribution of slow wave and rapid eye movement sleep as well as to the development of models to determine the amount and timing of sleep. One successful model postulates two processes. The first is process S, which is due to sleep pressure (and increases with time awake and is attributed to a 'sleep homeostat'. Process S reverses during slow wave sleep (when it is called process S'. The second is process C, which shows a daily rhythm that is parallel to the rhythm of core temperature. Processes S and C combine approximately additively to determine the times of sleep onset and waking. The model has proved useful in describing normal sleep in adults. Current work aims to identify the detailed nature of processes S and C. The model can also be applied to circumstances when the sleep-wake cycle is different from the norm in some way. These circumstances include: those who are poor sleepers or short sleepers; the role an individual's chronotype (a measure of how the timing of the individual's preferred sleep-wake cycle compares with the average for a population; and changes in the sleep-wake cycle with age, particularly in adolescence and aging, since individuals tend to prefer to go to sleep later during adolescence and earlier in old age. In all circumstances, the evidence that sleep times and architecture are altered and the possible causes of these changes (including altered S, S' and C processes are examined.

Unihemispheric sleep and asymmetrical sleep: behavioral, neurophysiological, and functional perspectives

Directory of Open Access Journals (Sweden)

Mascetti GG

2016-07-01

Full Text Available Gian Gastone Mascetti Department of General Psychology, University of Padova, Padova, Italy Abstract: Sleep is a behavior characterized by a typical body posture, both eyes' closure, raised sensory threshold, distinctive electrographic signs, and a marked decrease of motor activity. In addition, sleep is a periodically necessary behavior and therefore, in the majority of animals, it involves the whole brain and body. However, certain marine mammals and species of birds show a different sleep behavior, in which one cerebral hemisphere sleeps while the other is awake. In dolphins, eared seals, and manatees, unihemispheric sleep allows them to have the benefits of sleep, breathing, thermoregulation, and vigilance. In birds, antipredation vigilance is the main function of unihemispheric sleep, but in domestic chicks, it is also associated with brain lateralization or dominance in the control of behavior. Compared to bihemispheric sleep, unihemispheric sleep would mean a reduction of the time spent sleeping and of the associated recovery processes. However, the behavior and health of aquatic mammals and birds does not seem at all impaired by the reduction of sleep. The neural mechanisms of unihemispheric sleep are unknown, but assuming that the neural structures involved in sleep in cetaceans, seals, and birds are similar to those of terrestrial mammals, it is suggested that they involve the interaction of structures of the hypothalamus, basal forebrain, and brain stem. The neural mechanisms promoting wakefulness dominate one side of the brain, while those promoting sleep predominates the other side. For cetaceans, unihemispheric sleep is the only way to sleep, while in seals and birds, unihemispheric sleep events are intermingled with bihemispheric and rapid eye movement sleep events. Electroencephalogram hemispheric asymmetries are also reported during bihemispheric sleep, at awakening, and at sleep onset, as well as being associated with a use

Sleep and circadian variability in people with delayed sleep-wake phase disorder versus healthy controls.

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Burgess, Helen J; Park, Margaret; Wyatt, James K; Rizvydeen, Muneer; Fogg, Louis F

2017-06-01

To compare sleep and circadian variability in adults with delayed sleep-wake phase disorder (DSWPD) to healthy controls. Forty participants (22 DSWPD, 18 healthy controls) completed a ten-day protocol, consisting of DLMO assessments on two consecutive nights, a five-day study break, followed by two more DLMO assessments. All participants were instructed to sleep within one hour of their self-reported average sleep schedule for the last four days of the study break. We analyzed the participants' wrist actigraphy data during these four days to examine intraindividual variability in sleep timing, duration and efficiency. We also examined shifts in the DLMO from before and after the study break. Under the same conditions, people with DSWPD had significantly more variable wake times and total sleep time than healthy controls (p ≤ 0.015). Intraindividual variability in sleep onset time and sleep efficiency was similar between the two groups (p ≥ 0.30). The DLMO was relatively stable across the study break, with only 11% of controls but 27% of DSWPDs showed more than a one hour shift in the DLMO. Only in the DSWPD sample was greater sleep variability associated with a larger shift in the DLMO (r = 0.46, p = 0.03). These results suggest that intraindividual variability in sleep can be higher in DSWPD versus healthy controls, and this may impact variability in the DLMO. DSWPD patients with higher intraindividual variability in sleep are more likely to have a shifting DLMO, which could impact sleep symptoms and the optimal timing of light and/or melatonin treatment for DSWPD. Circadian Phase Assessments at Home, http://clinicaltrials.gov/show/NCT01487252, NCT01487252. Copyright © 2017 Elsevier B.V. All rights reserved.

Diurnal rhythms in the human urine metabolome during sleep and total sleep deprivation.

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Giskeødegård, Guro F; Davies, Sarah K; Revell, Victoria L; Keun, Hector; Skene, Debra J

2015-10-09

Understanding how metabolite levels change over the 24 hour day is of crucial importance for clinical and epidemiological studies. Additionally, the association between sleep deprivation and metabolic disorders such as diabetes and obesity requires investigation into the links between sleep and metabolism. Here, we characterise time-of-day variation and the effects of sleep deprivation on urinary metabolite profiles. Healthy male participants (n = 15) completed an in-laboratory study comprising one 24 h sleep/wake cycle prior to 24 h of continual wakefulness under highly controlled environmental conditions. Urine samples were collected over set 2-8 h intervals and analysed by (1)H NMR spectroscopy. Significant changes were observed with respect to both time of day and sleep deprivation. Of 32 identified metabolites, 7 (22%) exhibited cosine rhythmicity over at least one 24 h period; 5 exhibiting a cosine rhythm on both days. Eight metabolites significantly increased during sleep deprivation compared with sleep (taurine, formate, citrate, 3-indoxyl sulfate, carnitine, 3-hydroxyisobutyrate, TMAO and acetate) and 8 significantly decreased (dimethylamine, 4-DTA, creatinine, ascorbate, 2-hydroxyisobutyrate, allantoin, 4-DEA, 4-hydroxyphenylacetate). These data indicate that sampling time, the presence or absence of sleep and the response to sleep deprivation are highly relevant when identifying biomarkers in urinary metabolic profiling studies.

An approach to understanding sleep and depressed mood in adolescents: person-centred sleep classification.

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Shochat, Tamar; Barker, David H; Sharkey, Katherine M; Van Reen, Eliza; Roane, Brandy M; Carskadon, Mary A

2017-12-01

Depressive mood in youth has been associated with distinct sleep dimensions, such as timing, duration and quality. To identify discrete sleep phenotypes, we applied person-centred analysis (latent class mixture models) based on self-reported sleep patterns and quality, and examined associations between phenotypes and mood in high-school seniors. Students (n = 1451; mean age = 18.4 ± 0.3 years; 648 M) completed a survey near the end of high-school. Indicators used for classification included school night bed- and rise-times, differences between non-school night and school night bed- and rise-times, sleep-onset latency, number of awakenings, naps, and sleep quality and disturbance. Mood was measured using the total score on the Center for Epidemiologic Studies-Depression Scale. One-way anova tested differences between phenotype for mood. Fit indexes were split between 3-, 4- and 5-phenotype solutions. For all solutions, between phenotype differences were shown for all indicators: bedtime showed the largest difference; thus, classes were labelled from earliest to latest bedtime as 'A' (n = 751), 'B' (n = 428) and 'C' (n = 272) in the 3-class solution. Class B showed the lowest sleep disturbances and remained stable, whereas classes C and A each split in the 4- and 5-class solutions, respectively. Associations with mood were consistent, albeit small, with class B showing the lowest scores. Person-centred analysis identified sleep phenotypes that differed in mood, such that those with the fewest depressive symptoms had moderate sleep timing, shorter sleep-onset latencies and fewer arousals. Sleep characteristics in these groups may add to our understanding of how sleep and depressed mood associate in teens. © 2017 European Sleep Research Society.

Prioritizing sleep for healthy work schedules

Science.gov (United States)

2012-01-01

Good sleep is advantageous to the quality of life. Sleep-related benefits are particularly helpful for the working class, since poor or inadequate amounts of sleep degrade work productivity and overall health. This review paper explores the essential role of sleep in healthy work schedules and primarily focuses on the timing of sleep in relation to the work period (that is, before, during and after work). Data from laboratory, field and modeling studies indicate that consistent amounts of sleep prior to work are fundamental to improved performance and alertness in the workplace. In addition, planned naps taken during work maintain appropriate levels of waking function for both daytime and night-time work. Clearly, sufficient sleep after work is vital in promoting recovery from fatigue. Recent data also suggest that the time interval between shifts should be adjusted according to the biological timing of sleep. Although sleep is more likely to be replaced by job and other activities in the real life, research shows that it is worthwhile to revise the work schedules in order to optimize sleep before, sometime during and after the work period. Therefore, we suggest establishing work-sleep balance, similar to work-life balance, as a principle for designing and improving work schedules. PMID:22738292

Prioritizing sleep for healthy work schedules

Directory of Open Access Journals (Sweden)

Takahashi Masaya

2012-03-01

Full Text Available Abstract Good sleep is advantageous to the quality of life. Sleep-related benefits are particularly helpful for the working class, since poor or inadequate amounts of sleep degrade work productivity and overall health. This review paper explores the essential role of sleep in healthy work schedules and primarily focuses on the timing of sleep in relation to the work period (that is, before, during and after work. Data from laboratory, field and modeling studies indicate that consistent amounts of sleep prior to work are fundamental to improved performance and alertness in the workplace. In addition, planned naps taken during work maintain appropriate levels of waking function for both daytime and night-time work. Clearly, sufficient sleep after work is vital in promoting recovery from fatigue. Recent data also suggest that the time interval between shifts should be adjusted according to the biological timing of sleep. Although sleep is more likely to be replaced by job and other activities in the real life, research shows that it is worthwhile to revise the work schedules in order to optimize sleep before, sometime during and after the work period. Therefore, we suggest establishing work-sleep balance, similar to work-life balance, as a principle for designing and improving work schedules.

Prioritizing sleep for healthy work schedules.

Science.gov (United States)

Takahashi, Masaya

2012-03-13

Good sleep is advantageous to the quality of life. Sleep-related benefits are particularly helpful for the working class, since poor or inadequate amounts of sleep degrade work productivity and overall health. This review paper explores the essential role of sleep in healthy work schedules and primarily focuses on the timing of sleep in relation to the work period (that is, before, during and after work). Data from laboratory, field and modeling studies indicate that consistent amounts of sleep prior to work are fundamental to improved performance and alertness in the workplace. In addition, planned naps taken during work maintain appropriate levels of waking function for both daytime and night-time work. Clearly, sufficient sleep after work is vital in promoting recovery from fatigue. Recent data also suggest that the time interval between shifts should be adjusted according to the biological timing of sleep. Although sleep is more likely to be replaced by job and other activities in the real life, research shows that it is worthwhile to revise the work schedules in order to optimize sleep before, sometime during and after the work period. Therefore, we suggest establishing work-sleep balance, similar to work-life balance, as a principle for designing and improving work schedules.

Unihemispheric sleep and asymmetrical sleep: behavioral, neurophysiological, and functional perspectives.

Science.gov (United States)

Mascetti, Gian Gastone

2016-01-01

Sleep is a behavior characterized by a typical body posture, both eyes' closure, raised sensory threshold, distinctive electrographic signs, and a marked decrease of motor activity. In addition, sleep is a periodically necessary behavior and therefore, in the majority of animals, it involves the whole brain and body. However, certain marine mammals and species of birds show a different sleep behavior, in which one cerebral hemisphere sleeps while the other is awake. In dolphins, eared seals, and manatees, unihemispheric sleep allows them to have the benefits of sleep, breathing, thermoregulation, and vigilance. In birds, antipredation vigilance is the main function of unihemispheric sleep, but in domestic chicks, it is also associated with brain lateralization or dominance in the control of behavior. Compared to bihemispheric sleep, unihemispheric sleep would mean a reduction of the time spent sleeping and of the associated recovery processes. However, the behavior and health of aquatic mammals and birds does not seem at all impaired by the reduction of sleep. The neural mechanisms of unihemispheric sleep are unknown, but assuming that the neural structures involved in sleep in cetaceans, seals, and birds are similar to those of terrestrial mammals, it is suggested that they involve the interaction of structures of the hypothalamus, basal forebrain, and brain stem. The neural mechanisms promoting wakefulness dominate one side of the brain, while those promoting sleep predominates the other side. For cetaceans, unihemispheric sleep is the only way to sleep, while in seals and birds, unihemispheric sleep events are intermingled with bihemispheric and rapid eye movement sleep events. Electroencephalogram hemispheric asymmetries are also reported during bihemispheric sleep, at awakening, and at sleep onset, as well as being associated with a use-dependent process (local sleep).

Sitting and television viewing: novel risk factors for sleep disturbance and apnea risk? results from the 2013 National Sleep Foundation Sleep in America Poll.

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Buman, Matthew P; Kline, Christopher E; Youngstedt, Shawn D; Phillips, Barbara; Tulio de Mello, Marco; Hirshkowitz, Max

2015-03-01

Excess sitting is emerging as a novel risk factor for cardiovascular disease, diabetes, mental illness, and all-cause mortality. Physical activity, distinct from sitting, is associated with better sleep and lower risk for OSA, yet relationships among sitting behaviors and sleep/OSA remain unknown. We examined whether total sitting time and sitting while viewing television were associated with sleep duration and quality, OSA risk, and sleepiness. The 2013 National Sleep Foundation Sleep in America Poll was a cross-sectional study of 1,000 adults aged 23 to 60 years. Total sitting time, time watching television while sitting, sleep duration and quality, OSA risk, and daytime sleepiness were assessed. After adjusting for confounding factors (including BMI and physical activity), each additional hour per day of total sitting was associated with greater odds of poor sleep quality (OR [95% CI] = 1.06 [1.01, 1.11]) but not with other sleep metrics (including sleep duration), OSA risk, or daytime sleepiness. For television viewing while sitting, each additional hour per day was associated with greater odds of long sleep onset latency (≥ 30 min) (OR = 1.15 [1.04, 1.27]), waking up too early in the morning (OR = 1.12 [1.03, 1.23]), poor sleep quality (OR = 1.12 [1.02, 1.24]), and "high risk" for OSA (OR = 1.15 [1.04, 1.28]). Based upon an interaction analysis, regular physical activity was protective against OSA risk associated with television viewing (P = .04). Excess sitting was associated with relatively poor sleep quality. Sitting while watching television was associated with relatively poor sleep quality and OSA risk and may be an important risk factor for sleep disturbance and apnea risk.

Does the duration and time of sleep increase the risk of allergic rhinitis? Results of the 6-year nationwide Korea youth risk behavior web-based survey.

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Kwon, Jeoung A; Lee, Minjee; Yoo, Ki-Bong; Park, Eun-Cheol

2013-01-01

Allergic rhinitis (AR) is the most common chronic disorder in the pediatric population. Although several studies have investigated the correlation between AR and sleep-related issues, the association between the duration and time of sleep and AR has not been analyzed in long-term national data. This study investigated the relationship between sleep time and duration and AR risk in middle- and high-school students (adolescents aged 12-18). We analyzed national data from the Korea Youth Risk Behavior Web-based Survey by the Korea Centers for Disease Control and Prevention from 2007-2012. The sample size was 274,480, with an average response rate of 96.2%. Multivariate logistic regression analyses were conducted to determine the relationship between sleep and AR risk. Furthermore, to determine the best-fitted model among independent variables such as sleep duration, sleep time, and the combination of sleep duration and sleep time, we used Akaike Information Criteria (AIC) to compare models. A total of 43,337 boys and 41,665 girls reported a diagnosis of AR at baseline. The odds ratio increased with age and with higher education and economic status of the parents. Further, students in mid-sized and large cities had stronger relationships to AR than those in small cities. In both genders, AR was associated with depression and suicidal ideation. In the analysis of sleep duration and sleep time, the odds ratio increased in both genders when sleep duration was sleep was later than 24:00 hours. Our results indicate an association between sleep time and duration and AR. This study is the first to focus on the relationship between sleep duration and time and AR in national survey data collected over 6 years.

Sleep Duration, Positive Attitude toward Life, and Academic Achievement: The Role of Daytime Tiredness, Behavioral Persistence, and School Start Times

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Perkinson-Gloor, Nadine; Lemola, Sakari; Grob, Alexander

2013-01-01

Sleep timing undergoes profound changes during adolescence, often resulting in inadequate sleep duration. The present study examines the relationship of sleep duration with positive attitude toward life and academic achievement in a sample of 2716 adolescents in Switzerland (mean age: 15.4 years, SD = 0.8), and whether this relationship is…

Sleep-monitoring, experiment M133. [electronic recording system for automatic analysis of human sleep patterns

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Frost, J. D., Jr.; Salamy, J. G.

1973-01-01

The Skylab sleep-monitoring experiment simulated the timelines and environment expected during a 56-day Skylab mission. Two crewmembers utilized the data acquisition and analysis hardware, and their sleep characteristics were studied in an online fashion during a number of all night recording sessions. Comparison of the results of online automatic analysis with those of postmission visual data analysis was favorable, confirming the feasibility of obtaining reliable objective information concerning sleep characteristics during the Skylab missions. One crewmember exhibited definite changes in certain sleep characteristics (e.g., increased sleep latency, increased time Awake during first third of night, and decreased total sleep time) during the mission.

The timing of the circadian clock and sleep differ between napping and non-napping toddlers

OpenAIRE

Akacem, Lameese D; Simpkin, Charles T; Carskadon, Mary A; Wright, Kenneth P; Jenni, Oskar G; Achermann, Peter; LeBourgeois, Monique K

2015-01-01

The timing of the internal circadian clock shows large inter-individual variability across the lifespan. Although the sleep-wakefulness pattern of most toddlers includes an afternoon nap, the association between napping and circadian phase in early childhood remains unexplored. This study examined differences in circadian phase and sleep between napping and non-napping toddlers. Data were collected on 20 toddlers (34.2±2.0 months; 12 females; 15 nappers). Children followed their habitual napp...

Sleep is not just for the brain: transcriptional responses to sleep in peripheral tissues

OpenAIRE

Anafi, Ron C; Pellegrino, Renata; Shockley, Keith R; Romer, Micah; Tufik, Sergio; Pack, Allan I

2013-01-01

Background Many have assumed that the primary function of sleep is for the brain. We evaluated the molecular consequences of sleep and sleep deprivation outside the brain, in heart and lung. Using microarrays we compared gene expression in tissue from sleeping and sleep deprived mice euthanized at the same diurnal times. Results In each tissue, nearly two thousand genes demonstrated statistically significant differential expression as a function of sleep/wake behavioral state. To mitigate the...

Upper Airway Resistance Syndrome Patients Have Worse Sleep Quality Compared to Mild Obstructive Sleep Apnea.

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Luciana Balester Mello de Godoy

Full Text Available To compare sleep quality and sustained attention of patients with Upper Airway Resistance Syndrome (UARS, mild Obstructive Sleep Apnea (OSA and normal individuals.UARS criteria were presence of excessive daytime sleepiness (Epworth Sleepiness Scale-ESS-≥ 10 and/or fatigue (Modified Fatigue Impact Scale-MFIS-≥ 38 associated to Apnea/hypopnea index (AHI ≤ 5 and Respiratory Disturbance Index (RDI > 5 events/hour of sleep or more than 30% of total sleep time with flow limitation. Mild OSA was considered if the presence of excessive daytime sleepiness (ESS ≥ 10 and/or fatigue (MFIS ≥ 38 associated to AHI ≥ 5 and ≤ 15 events/hour. "Control group" criteria were AHI < 5 events/hour and RDI ≤ 5 events/hour and ESS ≤ 9, without any sleep, clinical, neurological or psychiatric disorder. 115 individuals (34 UARS and 47 mild OSA patients and 34 individuals in "control group", adjusted for age, gender, body mass index (BMI and schooling years, performed sleep questionnaires and sustained attention evaluation. Psychomotor Vigilance Task (PVT was performed five times (each two hours from 8 a.m. to 4 p.m.UARS patients had worse sleep quality (Functional Outcomes of Sleep Questionnaire-FOSQ-and Pittsburgh Sleep Quality Index-PSQI: p < 0.05 and more fatigue than mild OSA patients (p = 0.003 and scored significantly higher in both Beck inventories than "control group" (p < 0.02. UARS patients had more lapses early in the morning (in time 1 compared to the results in the afternoon (time 5 than mild OSA (p = 0.02. Mild OSA patients had more lapses in times 2 than in time 5 compared to "control group" (p = 0.04.UARS patients have a worse sleep quality, more fatigue and a worse early morning sustained attention compared to mild OSA. These last had a worse sustained attention than controls.

The role of sleep and sleep deprivation in consolidating fear memories.

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Menz, M M; Rihm, J S; Salari, N; Born, J; Kalisch, R; Pape, H C; Marshall, L; Büchel, C

2013-07-15

Sleep, in particular REM sleep, has been shown to improve the consolidation of emotional memories. Here, we investigated the role of sleep and sleep deprivation on the consolidation of fear memories and underlying neuronal mechanisms. We employed a Pavlovian fear conditioning paradigm either followed by a night of polysomnographically monitored sleep, or wakefulness in forty healthy participants. Recall of learned fear was better after sleep, as indicated by stronger explicitly perceived anxiety and autonomous nervous responses. These effects were positively correlated with the preceding time spent in REM sleep and paralleled by activation of the basolateral amygdala. These findings suggest REM sleep-associated consolidation of fear memory in the human amygdala. In view of the critical participation of fear learning mechanisms in the etiology of anxiety and post-traumatic stress disorder, deprivation of REM sleep after exposure to distressing events is an interesting target for further investigation. Copyright © 2013 Elsevier Inc. All rights reserved.

Individual differences in compliance and agreement for sleep logs and wrist actigraphy: A longitudinal study of naturalistic sleep in healthy adults.

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Steven M Thurman

Full Text Available There is extensive laboratory research studying the effects of acute sleep deprivation on biological and cognitive functions, yet much less is known about naturalistic patterns of sleep loss and the potential impact on daily or weekly functioning of an individual. Longitudinal studies are needed to advance our understanding of relationships between naturalistic sleep and fluctuations in human health and performance, but it is first necessary to understand the efficacy of current tools for long-term sleep monitoring. The present study used wrist actigraphy and sleep log diaries to obtain daily measurements of sleep from 30 healthy adults for up to 16 consecutive weeks. We used non-parametric Bland-Altman analysis and correlation coefficients to calculate agreement between subjectively and objectively measured variables including sleep onset time, sleep offset time, sleep onset latency, number of awakenings, the amount of wake time after sleep onset, and total sleep time. We also examined compliance data on the submission of daily sleep logs according to the experimental protocol. Overall, we found strong agreement for sleep onset and sleep offset times, but relatively poor agreement for variables related to wakefulness including sleep onset latency, awakenings, and wake after sleep onset. Compliance tended to decrease significantly over time according to a linear function, but there were substantial individual differences in overall compliance rates. There were also individual differences in agreement that could be explained, in part, by differences in compliance. Individuals who were consistently more compliant over time also tended to show the best agreement and lower scores on behavioral avoidance scale (BIS. Our results provide evidence for convergent validity in measuring sleep onset and sleep offset with wrist actigraphy and sleep logs, and we conclude by proposing an analysis method to mitigate the impact of non-compliance and measurement

Sleep Spindle Detection and Prediction Using a Mixture of Time Series and Chaotic Features

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Amin Hekmatmanesh

2017-01-01

Full Text Available It is well established that sleep spindles (bursts of oscillatory brain electrical activity are significant indicators of learning, memory and some disease states. Therefore, many attempts have been made to detect these hallmark patterns automatically. In this pilot investigation, we paid special attention to nonlinear chaotic features of EEG signals (in combination with linear features to investigate the detection and prediction of sleep spindles. These nonlinear features included: Higuchi's, Katz's and Sevcik's Fractal Dimensions, as well as the Largest Lyapunov Exponent and Kolmogorov's Entropy. It was shown that the intensity map of various nonlinear features derived from the constructive interference of spindle signals could improve the detection of the sleep spindles. It was also observed that the prediction of sleep spindles could be facilitated by means of the analysis of these maps. Two well-known classifiers, namely the Multi-Layer Perceptron (MLP and the K-Nearest Neighbor (KNN were used to distinguish between spindle and non-spindle patterns. The MLP classifier produced a~high discriminative capacity (accuracy = 94.93%, sensitivity = 94.31% and specificity = 95.28% with significant robustness (accuracy ranging from 91.33% to 94.93%, sensitivity varying from 91.20% to 94.31%, and specificity extending from 89.79% to 95.28% in separating spindles from non-spindles. This classifier also generated the best results in predicting sleep spindles based on chaotic features. In addition, the MLP was used to find out the best time window for predicting the sleep spindles, with the experimental results reaching 97.96% accuracy.

Improvement in Obstructive Sleep Apnea Diagnosis and Management Wait Times: A Retrospective Analysis of a Home Management Pathway for Obstructive Sleep Apnea

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Samuel Alan Stewart

2015-01-01

Full Text Available Obstructive sleep apnea is a common condition within the Canadian population. The current gold standard for diagnosis and management of patients is in-laboratory (in-lab polysomnography; however, the limited availability of testing options for patients has led to long wait times and increased disease burden within the population. The Sleep Research Laboratory in Saskatoon (Saskatchewan implemented a home management program to run in parallel with the in-lab system several years ago in an effort to increase their capacity and reduce wait times. The present study was a retrospective analysis of all patients referred to the program between 2009 and 2012. The home management system has improved wait times by diagnosing and managing up to one-half of the referred patient population, reducing the wait for in-lab treatment from a median of 152 days in 2009 to 92 days in 2012 (P<0.0001. Moving forward, home management can provide a viable alternative to in-lab testing for patients who meet strict entry criteria, reducing the in-lab workload and, ultimately, reducing wait times.

Nocturnal Polyuria in Older Women with Urge Urinary Incontinence: Role of Sleep Quality, Time in Bed and Medications Used.

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Tyagi, Shachi; Perera, Subashan; Clarkson, Becky D; Tadic, Stasa D; Resnick, Neil M

2017-03-01

Nocturia is common and bothersome in older adults, especially those who are also incontinent. Since nocturnal polyuria is a major contributor, we examined factors associated with nocturnal polyuria in this population to identify those possibly amenable to intervention. We analyzed baseline data from 2 previously completed studies of urge urinary incontinence. The studies involved 284 women (mean age ± SD 72.9 ± 7.9 years) who also completed 3-day voiding diaries. Participants with a nocturnal polyuria index greater than 33% were categorized as having nocturnal polyuria (nocturnal polyuria index = nocturnal urinary volume per 24-hour urine volume). Associations between nocturnal polyuria and various demographic, clinical and sleep related parameters were determined. Overall 55% of the participants had nocturnal polyuria. Multivariable regression analysis revealed that age, body mass index, use of angiotensin converting enzyme inhibitor/angiotensin receptor blocker, time spent in bed and duration of first uninterrupted sleep were independent correlates of nocturnal polyuria. Participants with a larger nocturnal excretion reported a shorter duration of uninterrupted sleep before first awakening to void and worse sleep quality despite spending similar time in bed. Body mass index, use of angiotensin converting enzyme inhibitor/angiotensin receptor blockers, time in bed and duration of uninterrupted sleep before first awakening to void are independently associated with nocturnal polyuria in older women with urge urinary incontinence, and are potentially modifiable. These findings also confirm the association between sleep and nocturnal polyuria. Further studies should explore whether interventions to reduce nocturnal polyuria and/or increase the duration of uninterrupted sleep before first awakening to void would help to improve sleep quality in this population and thereby reduce or eliminate the need for sedative hypnotics. Copyright © 2017 American Urological

Creatine supplementation reduces sleep need and homeostatic sleep pressure in rats.

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Dworak, Markus; Kim, Tae; Mccarley, Robert W; Basheer, Radhika

2017-06-01

Sleep has been postulated to promote brain energy restoration. It is as yet unknown if increasing the energy availability within the brain reduces sleep need. The guanidine amino acid creatine (Cr) is a well-known energy booster in cellular energy homeostasis. Oral Cr-monohydrate supplementation (CS) increases exercise performance and has been shown to have substantial effects on cognitive performance, neuroprotection and circadian rhythms. The effect of CS on cellular high-energy molecules and sleep-wake behaviour is unclear. Here, we examined the sleep-wake behaviour and brain energy metabolism before and after 4-week-long oral administration of CS in the rat. CS decreased total sleep time and non-rapid eye movement (NREM) sleep significantly during the light (inactive) but not during the dark (active) period. NREM sleep and NREM delta activity were decreased significantly in CS rats after 6 h of sleep deprivation. Biochemical analysis of brain energy metabolites showed a tendency to increase in phosphocreatine after CS, while cellular adenosine triphosphate (ATP) level decreased. Microdialysis analysis showed that the sleep deprivation-induced increase in extracellular adenosine was attenuated after CS. These results suggest that CS reduces sleep need and homeostatic sleep pressure in rats, thereby indicating its potential in the treatment of sleep-related disorders. © 2017 European Sleep Research Society.