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We are unresponsive during slow-wave sleep but continue monitoring external events for survival. Our brain wakens us when danger is imminent. If events are non-threatening, our brain might store them for later consideration to improve decision-making. To test this hypothesis, we examined whether novel vocabulary consisting of simultaneously played pseudowords and translation words are encoded/stored during sleep, and which neural-electrical events facilitate encoding/storage. An algorithm for brain-state-dependent stimulation selectively targeted word pairs to slow-wave peaks or troughs. Retrieval tests were given 12 and 36 hr later. These tests required decisions regarding the semantic category of previously sleep-played pseudowords. The sleep-played vocabulary influenced awake decision-making 36 hr later, if targeted to troughs. The words’ linguistic processing raised neural complexity. The words’ semantic-associative encoding was supported by increased theta power during the ensuing peak. Fast-spindle power ramped up during a second peak likely aiding consolidation. Hence, new vocabulary played during slow-wave sleep was stored and influenced decision-making days later.

Huxley's Brave New World (1932) offers a nightmarish portrait of a futuristic world where human beings are reduced to the level of automations for establishing stability. In fact, Huxley's portrayal of the World State is heavily influenced by the socio-political climate of his time. Contemplating the possible misuse of emerging technologies by rulers for perpetuation of power, Huxley attempts to alert the readers about the perils of mass culture which diminish people's ability to think critically. Brushed aside as an insignificant work by many critics initially, the novel's social relevance and Huxley's concern for social welfare was later felt, the application of Marxist and Neo-Marxist literary principles to it indicating that it continues to remain relevant in the twenty-first century. Marxism interprets history in terms of class struggle. It affirms that the modes of production of material life condition social, political and intellectual life process in general. The Marxian notion that those who control material production have control over the rest of the society is taken literally in Huxley's Brave New World where the World State owns the production of human progeny. However, the production of babies in Hatcheries, chemical conditioning of embryos and hypnopaedia ensure that class struggle is avoided in the imaginary world, as the citizens are made to accept their social status without dissent. It would, however, be simplistic to assume that Huxley's dystopia aims merely to terrorise modern society. In the words of Raffaella Baccolini "...utopia is always maintained ... only outside the text" (520) and the readers are expected to consider dystopias only as warnings, so that they can prevent them from becoming reality. [ABSTRACT FROM AUTHOR]

We are unresponsive during slow-wave sleep but continue monitoring external events for survival. Our brain wakens us when danger is imminent. If events are non-threatening, our brain might store them for later consideration to improve decision-making. To test this hypothesis, we examined whether novel vocabulary consisting of simultaneously played pseudowords and translation words are encoded/stored during sleep, and which neural-electrical events facilitate encoding/storage. An algorithm for brain-state-dependent stimulation selectively targeted word pairs to slow-wave peaks or troughs. Retrieval tests were given 12 and 36 hr later. These tests required decisions regarding the semantic category of previously sleep-played pseudowords. The sleep-played vocabulary influenced awake decision-making 36 hr later, if targeted to troughs. The words' linguistic processing raised neural complexity. The words' semantic-associative encoding was supported by increased theta power during the ensuing peak. Fast-spindle power ramped up during a second peak likely aiding consolidation. Hence, new vocabulary played during slow-wave sleep was stored and influenced decision-making days later., Competing Interests: FS, SR, KH No competing interests declared, (© 2023, Schmidig et al.)

Sleep helps to consolidate previously acquired memories. Whether new information such as languages and other useful skills can also be learned during sleep has been debated for over a century, however, the sporadic studies' different objectives and varied methodologies make it difficult to draw definitive conclusions. This review provides a comprehensive overview of the history of sleep learning research conducted in humans, from its empirical beginnings in the 1940s to the present day. Synthesizing the findings from 51 research papers, we show that several studies support the notion that simpler forms of learning, such as habituation and conditioning, are possible during sleep. In contrast, the findings for more complex, applied learning (e.g., learning a new language during sleep) are more divergent. While there is often an indication of processing and learning during sleep when looking at neural markers, behavioral evidence for the transfer of new knowledge to wake remains inconclusive. We close by critically examining the limitations and assumptions that have contributed to the discrepancies in the literature and highlight promising new directions in the field. [ABSTRACT FROM AUTHOR]

Highlights • The effect of sleep on false memory formation was studied. • False recognition rate was higher after sleep than after daytime wakefulness. • The higher false recognition rate after sleep was due to higher phantom recollection. • Our findings suggest that sleep strengthens gist traces and promotes gist extraction. Abstract Sleep is known to benefit memory consolidation, but its effect on false memory is less clear. We applied the simplified conjoint recognition paradigm to investigate how sleep affects the cognitive processes behind correct or false recognition, according to fuzzy-trace theory, and measured the retrieval of verbatim traces, retrieval of gist traces, and phantom recollection. Participants studied 24 lists of semantically related words lacking the strongest common associate or theme word. Recognition was tested 12 h later, following either a night's sleep or daytime wakefulness. The recognition test featured studied words, nonstudied theme words (false recognition), and unrelated words. False recognition rate was higher after sleep than after daytime wakefulness. True recognition rate was the same. Analysis of the cognitive processes underlying recognition showed that phantom recollection was higher after sleep. Assuming that phantom recollection reflects the retrieval of strong gist traces, sleep may strengthen gist traces and promote gist extraction. [ABSTRACT FROM AUTHOR]

The article offers a report on sleeping presenting sleeping portraits of several people to explore the active nature of sleeping. It mentions sleep is the absence of performance, and the absence of conscious thinking; various concepts related to sleeping research; and observation of psychological aspects while sleeping.

There is now a plethora of evidence that children with sleep disordered breathing (SDB) show deficits in neurocognitive performance, behavioral impairments, and school performance. The following review will focus on the neurobehavioral impacts of SDB, pediatric sleep investigation challenges, potential mechanisms of behavioral and cognitive deficits in children with SDB, and the impact of SDB treatment. [ABSTRACT FROM AUTHOR]

Background: Chronotype manifestation often has a broad influence on sleep quality. One possible explanation for daytime impairments in evening types is the concept of 'social jetlag'. Social jetlag is caused by an incompatibility between circadian preference and the socially accepted rhythm. This can be declared as a social stressor. Objective: The association between chronotype, stress coping, and sleep quality was assessed in a pilot study. Materials and methods: A total of 75 female adults aged 20-41 years participated in the study and completely answered all questions. Various questionnaires including sociodemographic data, information about sleep quality (Pittsburgh Sleep Quality Index, PSQI), chronotype (morningness-eveningness questionnaire, MEQ), and stress coping (Stress Coping Style Questionnaire, SVF78) were applied. Results: Heightened use of maladaptive coping strategies is associated with a reduction in sleep quality. Chronotypes did not differ in terms of sleep quality and the coping strategies used. Conclusion: Maladaptive coping strategy use seems to have a negative influence on sleep quality. Preventive education in adaptive stress coping strategies and avoidance of maladaptive stress coping thus seems useful to reduce these adverse influences on sleep quality. [ABSTRACT FROM AUTHOR]

Background and Objectives: Sleep deprivation is a critical public health problem, especially in Korean adolescents. This study aimed to identify the association between sleep duration and dietary behaviors, physical activity, mental status, and nutritional status among high school students in South Korea. Methods and Study Design: Based on the data collected from the 2014 Korea Youth Risk Behavior Web-based Survey, 31.407 high school students who met the inclusion criteria were selected and the association between sleep duration and selected health risk factors was identified using multivariable logistic regression models. Results: The average daily sleep duration was 5.7 hours, and the mean BM1 was 21.3 kg/m2. Participants with shorter durations of sleep (<7 hours versus ≥7 hours of sleep) were more likely to feel sad or hopeless (adjusted OR, 1.09; 95% Cl. 1.00-1.18), have suicidal ideation (adjusted OR, 1.13; 95% Cl, 1.01-1.27), and feel much or very much stressed (adjusted OR. 1.82; 95% Cl. 1.66-2.00). Moreover, shorter sleep was associated with less frequent muscle-strengthening exercises, ≥3 times per week (adjusted OR. 0.86; 95% Cl. 0.78-0.94). and more frequent cracker consumption, ≥3 times per week (adjusted OR, 1.24; 95% Cl, 1.13-1.35). Conclusions: High school students in South Korea suffer from extreme sleep deprivation; only 16% of the students were found to have ≥7 hours of sleep during weekdays. Sleep education should be provided to students to improve their physical and mental health. [ABSTRACT FROM AUTHOR]

Background: Sleep disorders are often underreported to physicians by patients with allergies. This study aimed to characterize the sleep disorders associated with respiratory allergy to house dust mites (HDM) at the time of initiation of sublingual allergen immunotherapy (SLIT) in routine clinical practice. Methods: This prospective, cross-sectional, observational study was conducted between November 2014 and March 2015 at 189 French trial sites and included 1750 participants suffering from HDM allergy who were initiating SLIT. Participants aged less than 5 years old and those who had previously started an allergen immunotherapy (AIT) for HDM allergy were not enrolled in the study. Sleep disorders were assessed by self-administered questionnaires: the Epworth Sleepiness Scale (ESS), the Insomnia Severity Index (ISI) and a modified version of the Hotel Dieu-42 (HD-42) sleep disorder questionnaire. Logistic regression models adjusted for obesity, smoking status, asthma control and nasal obstruction were used to study the relationship between allergic rhinitis (AR) classification and sleep disorders/ complaints. Results: Of the 1786 participants enrolled, 1750 (907 adults and 843 children) composed the analysis population. The majority of participants (73.5% of adults and 65.8% of children) reported that their sleep disorders had prompted them to consult their physician. The most commonly observed sleep complaints were poor-quality sleep (50.3% of adults and 37.3% of children), snoring (48.1 and 41.4%, respectively) and nocturnal awakening (37.6 and 28.2%, respectively). Difficulties falling asleep were reported by 27.0% of adults and 24.7% of children. Adults and children suffering from severe persistent AR experienced sleep complaints significantly more often than participants with intermittent or mild persistent AR. Conclusions: This study highlights the high frequency of sleep disorders and their significant impact on patients with AR induced by HDM, in particular when AR is persistent and severe. Consequently, asking allergic patients about the quality of their sleep appears to be important, especially when the patient has persistent and severe AR. [ABSTRACT FROM AUTHOR]

Dim Light Melatonin Onset (DLMO) is a reliable marker of the endogenous circadian rhythm. To determine if sleep timing can predict DLMO, we investigated the relationship between sleep timing and DLMO in patients in various circadian sleep-wake rhythm disorders (CSWRDs), ages and genders. We found that correlations were only moderate between DLMO and sleep-onset in the complete data-set, but they increased in patients with delayed sleep-wake phase disorder (DSWPD), DSWPD patients with a regular sleep pattern and patients with advanced sleep-wake phase disorder (ASWPD); the levels of correlation werer = 0.542, 0.657, 0.728 and 0.814, respectively. In DSWPD patients with a regular sleep pattern, mid-sleep strongly correlated (r = 0.839) with DLMO. Correlation in other CSRWDs was not significant. DLMO, sleep-onset and age were most discriminated factors between the various CSRWDs. Estimation of DLMO is only possible in patients with ASWPD and in DSWPD patients with a regular sleep pattern. [ABSTRACT FROM PUBLISHER]

Recently, a number of authors have advocated the introduction of gross motor tasks into research on sleep-related motor offline learning. Such tasks are often designed to be more complex than traditional key-pressing tasks. However, until now, little effort has been undertaken to scrutinize the role of task complexity in any systematic way. Therefore, the effect of task complexity on the consolidation of gross motor sequence memory was examined by our group in a series of three experiments. Criterion tasks always required participants to produce unrestrained arm movement sequences by successively fitting a small peg into target holes on a pegboard. The sequences always followed a certain spatial pattern in the horizontal plane. The targets were visualized prior to each transport movement on a computer screen. The tasks differed with respect to sequence length and structural complexity. In each experiment, half of the participants initially learned the task in the morning and were retested 12 h later following a wake retention interval. The other half of the subjects underwent practice in the evening and was retested 12 h later following a night of sleep. The dependent variables were the error rate and total sequence execution time (inverse to the sequence execution speed). Performance generally improved during acquisition. The error rate was always low and remained stable during retention. The sequence execution time significantly decreased again following sleep but not after waking when the sequence length was long and structural complexity was high. However, sleep-related offline improvements were absent when the sequence length was short or when subjects performed a highly regular movement pattern. It is assumed that the occurrence of sleep-related offline performance improvements in sequential motor tasks is associated with a sufficient amount of motor task complexity. [ABSTRACT FROM AUTHOR]

Hcrt gene inactivation in mice leads to behavioral state instability, abnormal transitions to paradoxical sleep, and cataplexy, hallmarks of narcolepsy. Sleep homeostasis is, however, considered unimpaired in patients and narcoleptic mice. We find that whereas Hcrtko/ko mice respond to 6-h sleep deprivation (SD) with a slowwave sleep (SWS) EEG δ (1.0 to 4.0 Hz) power rebound like WT littermates, spontaneous waking fails to induce a δ power reflecting prior waking duration. This correlates with impaired θ (6.0 to 9.5 Hz) and fast-γ (55 to 80 Hz) activity in prior waking. We algorithmically identify a theta-dominated wakefulness (TDW) substate underlying motivated behaviors and typically preceding cataplexy in Hcrtko/ko mice. Hcrtko/ko mice fully implement TDW when waking is enforced, but spontaneous TDW episode duration is greatly reduced. A reformulation of the classic sleep homeostasis model, where homeostatic pressure rises exclusively in TDW rather than all waking, predicts δ power dynamics both in Hcrtko/ko and WT mouse baseline and recovery SWS. The low homeostatic impact of Hcrtko/ko mouse spontaneous waking correlates with decreased cortical expression of neuronal activityrelated genes (notably Bdnf, Egr1/Zif268, and Per2). Thus, spontaneous TDW stability relies on Hcrt to sustain θ/fast-γ network activity and associated plasticity, whereas other arousal circuits sustain TDW during SD. We propose that TDW identifies a discrete global brain activity mode that is regulated by contextdependent neuromodulators and acts as a major driver of sleep homeostasis. Hcrt loss in Hcrtko/ko mice causes impaired TDW maintenance in baseline wake and blunted δ power in SWS, reproducing, respectively, narcolepsy excessive daytime sleepiness and poor sleep quality. [ABSTRACT FROM AUTHOR]

This study examined mothers' and fathers' beliefs about responding to infant night wakings across the first year of life, changes in those beliefs, and how individual maternal and paternal beliefs and interparental discrepancy in beliefs about responding to infant night wakings related to parents' perceptions of coparenting quality. Participants were 167 mothers and 155 fathers who reported on their own beliefs about responding to infant night wakings and perceptions of coparenting quality when infants were 1, 3, 6, 9, and 12 months old. As predicted, mothers endorsed stronger beliefs about responding more immediately to infant night wakings than fathers, but for both parents these beliefs declined over the first year. Troubled beliefs about responding to infant night wakings predicted worse coparenting quality. In addition, the discrepancy between mothers' and fathers' beliefs predicted coparenting quality such that a larger discrepancy in parents' beliefs about responding to infant night wakings significantly predicted poorer perceptions of coparenting, particularly in the early months, but only when mothers endorsed stronger beliefs than fathers. Results emphasize the importance of communication and concordance in nighttime parenting practices for aspects of parents' coparenting relationship. Future research should consider the importance of examining domain-specific parenting practices and cognitions as well as interparental discrepancies when assessing coparenting quality. (PsycINFO Database Record [ABSTRACT FROM AUTHOR]

Although a substantial body of literature has explored the relationship between sleep and exercise, comprehensive reviews and definitive conclusions about the impact of exercise interventions on sleep are lacking. Electronic databases were searched for articles published between January 2013 and March 2017. Studies were included if they possessed either objective or subjective measures of sleep and an exercise intervention that followed the guidelines recommended by the American College of Sports Medicine. Thirty-four studies met these inclusion criteria. Twenty-nine studies concluded that exercise improved sleep quality or duration; however, four found no difference and one reported a negative impact of exercise on sleep. Study results varied most significantly due to participants’ age, health status, and the mode and intensity of exercise intervention. Mixed findings were reported for children, adolescents, and young adults. Interventions conducted with middle-aged and elderly adults reported more robust results. In these cases, exercise promoted increased sleep efficiency and duration regardless of the mode and intensity of activity, especially in populations suffering from disease. Our review suggests that sleep and exercise exert substantial positive effects on one another; however, to reach a true consensus, the mechanisms behind these observations must first be elucidated. [ABSTRACT FROM AUTHOR]

Sleep plays an active role in memory consolidation. Because children with Down syndrome ( DS) and Williams syndrome ( WS) experience significant problems with sleep and also with learning, we predicted that sleep-dependent memory consolidation would be impaired in these children when compared to typically developing ( TD) children. This is the first study to provide a cross-syndrome comparison of sleep-dependent learning in school-aged children. Children with DS ( n = 20) and WS ( n = 22) and TD children ( n = 33) were trained on the novel Animal Names task where they were taught pseudo-words as the personal names of ten farm and domestic animals, e.g. Basco the cat, with the aid of animal picture flashcards. They were retested following counterbalanced retention intervals of wake and sleep. Overall, TD children remembered significantly more words than both the DS and WS groups. In addition, their performance improved following night-time sleep, whereas performance over the wake retention interval remained stable, indicating an active role of sleep for memory consolidation. Task performance of children with DS did not significantly change following wake or sleep periods. However, children with DS who were initially trained in the morning continued to improve on the task at the following retests, so that performance on the final test was greater for children who had initially trained in the morning than those who trained in the evening. Children with WS improved on the task between training and the first retest, regardless of whether sleep or wake occurred during the retention interval. This suggests time-dependent rather than sleep-dependent learning in children with WS, or tiredness at the end of the first session and better performance once refreshed at the start of the second session, irrespective of the time of day. Contrary to expectations, sleep-dependent learning was not related to baseline level of performance. The findings have significant implications for educational strategies, and suggest that children with DS should be taught more important or difficult information in the morning when they are better able to learn, whilst children with WS should be allowed a time delay between learning phases to allow for time-dependent memory consolidation, and frequent breaks from learning so that they are refreshed and able to perform at their best. [ABSTRACT FROM AUTHOR]

Aim: To study the effect of hemispherotomy on electrical status epilepticus in sleep (ESES) and language development.Method: Children with a confirmed diagnosis of ESES prior to surgery and a minimum of 24 months of developmental follow-up data were compared with age-matched controls without ESES. Language quotients (LQs) were calculated before and after surgery.Results: Eleven patients (five females, six males) and 21 controls (11 females, 10 males) were included. Before surgery a significantly higher number of children in the study group (n=9) demonstrated severe developmental delay compared with children in the control group (n=13; p=0.015). In the study group ESES remitted immediately after surgery in 10 children, and a significant catch-up in LQs was observed in this group (preoperative mean 40.0 [standard deviation (SD) 22.2, interquartile range (IQR) 30.0-62.0]; postoperative mean 73.0 [SD 33.5, IQR 41.0-97.0]; p=0.037). There was no significant difference compared with controls at last follow-up after surgery (study group: five with severe impairment; control group: eight with severe impairment [p=0.971]). Overall, a favourable developmental outcome was associated with freedom from seizures (seizure-free group: median preoperative LQ 61.5, median postoperative LQ 78.0 [p=0.017]; seizure group: median preoperative LQ 35.5, median postoperative LQ 56.5 [p=0.273]) and antiepileptic drug withdrawal (off medication: median preoperative LQ 49.5, median postoperative LQ 78.0 [p=0.011]; on medication: median preoperative LQ 78.0, median postoperative LQ 83.5 [p=0.889]).Interpretation: Children with ESES showed significantly lower preoperative language abilities than children without ESES. In cases with remission of ESES after surgery, marked improvement in LQs was noticed. This improvement cannot be fully explained by seizure-freedom alone as seizure-free children without preoperative ESES showed less improvement. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate how hotel guests sleep and the factors that typically disturb sleep when staying in hotels. A total of 2504 respondents for the survey were recruited through a link in a national online newspaper. They were asked to provide information about demographics, how they slept in hotels, factors disturbing sleep in hotels and how sleep typically developed with length of stay in hotels. On average, the respondents reported sleeping somewhat less well in hotels than at home. Males, younger people and people suffering from insomnia reported better sleep in hotels than did females, older people and subjects not suffering from insomnia, respectively. The factor which most frequently disturbed sleep in hotels was poor pillows, followed by high room temperature, poor mattress, poor duvet, noise from the street, poor indoor climate, too much daylight from the windows and noise from the ventilation system. Nearly 50% of the respondents reported that sleep usually improved with length of stay, whereas only 8.4% reported that sleep deteriorated with length of stay. The results point to several factors which could be altered by simple means and thereby improve sleep in hotels. The present study is the first large-scale survey that investigates how hotel guests in general experience sleep in hotels. [ABSTRACT FROM AUTHOR]

A cross-sectional study on the different health effects following the usage of electronic devices among the university community residing in Selangor, Malaysia was carried out using an online self-administered questionnaire. The results showed the cumulative hours spent by respondents ( n = 304) on mobile phone, laptop, tablet and portable game console was 8.3 per day. The incidences of eye strain, memory lapse, fatigue, neck pain and back pain were reported. Bivariate analysis showed that these musculoskeletal problems were not associated with the rest interval while using the devices. The average 6.9 h of sleep per day and average 3.3 (0-6) in rating their sleep quality was recorded. The rate on sleep quality was significantly positive correlated ( p < 0.013) with sleep hours but negatively correlated ( p < 0.026) with hours spent on devices. Furthermore, respondents who left electronic device in switch-on mode while sleeping and kept in dormitory had poorer sleep quality compared to those who switched off. Insomnia symptoms were encountered among the respondents in regard to poor sleep quality, behaviours including leaving electronic device in switch-on mode while sleeping and use of the devices before sleep. Hence, it is advisable to reduce the electronic devices usage to enjoy better sleep quality. [ABSTRACT FROM AUTHOR]

Objective: Sleep problems and depression are common symptoms in dementia with Lewy bodies (DLB), where patients typically experience subjectively poor sleep quality, fatigue and excessive daytime sleepiness. However, whilst sleep disturbances have been linked to depression, this relationship has not received much attention in DLB. The present cross-sectional study addresses this by examining whether depressive symptoms are specifically associated with subjective sleep quality and daytime sleepiness in DLB, and by examining other contributory factors.Methods: DLB patients (n = 32) completed the Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS) and the 15-item Geriatric Depression Scale (GDS-15). Motor and cognitive functioning was also assessed. Pearson correlations were used to assess the relationship between GDS-15, ESS and PSQI scores.Results: GDS-15 scores were positively associated with both ESS (r = 0.51, p < 0.01) and PSQI (r = 0.59, p < 0.001) scores.Conclusions: Subjective poor sleep and daytime sleepiness were associated with depressive symptoms in DLB. Given the cross-sectional nature of the present study, the directionality of this relationship cannot be determined, although this association did not appear to be mediated by sleep quality or daytime sleepiness. Nevertheless, these findings have clinical relevance; daytime sleepiness or poor sleep quality might indicate depression in DLB, and subsequent work should examine whether the treatment of depression can reduce excessive daytime sleepiness and improve sleep quality in DLB patients. Alternatively, more rigorous screening for sleep problems in DLB might assist the treatment of depression. © 2015 The Authors. International Journal of Geriatric Psychiatry published by John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Many electrical devices have a sleep mode to reduce their power consumption. However, changing into and out of the sleep mode delays processing and consumes power without performing useful work. Different strategies to activate the sleep mode allow different trade-offs between power consumption and latency. In this paper, we calculate which effects delayed activation and deactivation of a queueing system have on power consumption and latency. To this end, we created a Markov model as an abstraction of queuing systems with sleep modes and added delayed activation and deactivation. We analytically determined the steady state distribution of model states and give closed formulas for both power consumption and latency depending on the rate of arrival, processing, activation, deactivation, activation delay, and deactivation delay. We use this result to show that, surprisingly, cases exist in which adding both an activation delay and a deactivation delay reduces both mean power consumption and mean latency. Our simulation results demonstrate that this also holds for other random distributions. This shows that the opposing effects of activation delay and deactivation delay do not necessarily cancel each other out but can be used to reduce both power consumption and latency at the same time. [ABSTRACT FROM AUTHOR]

Polysomnography (PSG) is the "gold standard" for monitoring sleep. Alternatives to PSG are of interest for clinical, research, and personal use. Wrist-worn actigraph devices have been utilized in research settings for measures of sleep for over two decades. Whether sleep measures from commercially available devices are similarly valid is unknown. We sought to determine the validity of five wearable devices: Basis Health Tracker, Misfit Shine, Fitbit Flex,Withings Pulse O2, and a research-based actigraph, Actiwatch Spectrum. We used Wilcoxon Signed Rank tests to assess differences between devices relative to PSG and correlational analysis to assess the strength of the relationship. Data loss was greatest for Fitbit and Misfit. For all devices, we found no difference and strong correlation of total sleep time with PSG. Sleep efficiency differed from PSG forWithings, Misfit, Fitbit, and Basis, while Actiwatch mean values did not differ from that of PSG. Only mean values of sleep efficiency (time asleep/time in bed) from Actiwatch correlated with PSG, yet this correlation was weak. Light sleep time differed from PSG (nREM1 + nREM2) for all devices. Measures of Deep sleep time did not differ from PSG (SWS + REM) for Basis. These results reveal the current strengths and limitations in sleep estimates produced by personal health monitoring devices and point to a need for future development. [ABSTRACT FROM AUTHOR]

Objectives: Acoustic stimulation synchronized to slow waves (SWs) can enhance these sleep features and facilitate memory consolidation during nocturnal sleep. Here, we investigated whether a similar benefit could be accrued following stimulation during an afternoon nap. We also evaluated the event-related dynamics of associated EEG spectral changes and their correlation with memory performance.Methods: Sixteen healthy young adults (mean age: 22 ± 1.4 years; nine males) were studied under two conditions: stimulation (STIM) and no stimulation (SHAM), in counter-balanced order. In the STIM condition, acoustic stimulation was delivered using blocks of five tones, each phase-locked to the SW up-state during a 90-min nap opportunity. In the SHAM condition, these time points were marked, but tones were not presented. Prior to the nap, participants learned 40 semantically related word pairs and immediate recall was tested. A delayed recall test was administered 45 min after awakening.Results: Compared to the SHAM condition, acoustic stimulation increased SW amplitude, theta, and fast spindle activity and attenuated the forgetting of word pairs (p values < 0.05).Conclusion: Phase-locked acoustic stimulation can promote sleep-dependent declarative memory during a daytime nap. This can be achieved by stimulation in Stage 2 and SWS without a requirement for high-amplitude slow wave detection. [ABSTRACT FROM AUTHOR]

Background: Theoretical models of Bipolar Disorder (BD) highlight that sleep disturbances may be a marker of underlying circadian dysregulation. However, few studies of sleep in BD have reported on the most prevalent circadian sleep abnormality, namely Delayed Sleep Phase (DSP).Methods: A cross-sectional study of 404 adults with BD who met published clinical criteria for insomnia, hypersomnia or DSP, and who had previously participated in a study of sleep in BD using a comprehensive structured interview assessment.Results: About 10% of BD cases with a sleep problem met criteria for a DSP profile. The DSP group was younger and had a higher mean Body Mass Index (BMI) than the other groups. Also, DSP cases were significantly more likely to be prescribed mood stabilizers and antidepressant than insomnia cases. An exploratory analysis of selected symptom item ratings indicated that DSP was significantly more likely to be associated with impaired energy and activity levels.Limitations: The cross-sectional design precludes examination of longitudinal changes. DSP is identified by sleep profile, not by diagnostic criteria or objective sleep records such as actigraphy. The study uses data from a previous study to identify and examine the DSP group.Conclusions: The DSP group identified in this study can be differentiated from hypersomnia and insomnia groups on the basis of clinical and demographic features. The association of DSP with younger age, higher BMI and impaired energy and activity also suggest that this clinical profile may be a good proxy for underlying circadian dysregulation. [ABSTRACT FROM AUTHOR]

PREVIOUS RESEARCH HAS SHOWN THAT SLEEP facilitates skill acquisition by consolidating recent memories into a stabilized form. The way in which sleep benefits the acquisition of a musical skill, however, is unclear. This is because previous studies have not dissociated the extent to which sleep consolidates learned motoric patterns from the conceptual structure of the music. We thus designed two experiments in which pianists performed short pieces - designed to separate conceptual from motoric errors - over the course of a day. In Experiment 1, participants were trained in the morning and tested immediately, 12 hours, and 24 hours after training. While both motor and conceptual errors increased over a waking retention interval, only conceptual errors were significantly reduced after sleep. Moreover, individuals who reported spending more time "playing by ear" showed greater reductions of conceptual errors after sleep. A second control experiment, in which participants were trained in the evening and tested immediately - as well as 12 hours - after training, confirmed that the results from Experiment 1 could not be attributed solely to circadian confounds or to elapsed time since training. Together, these results suggest that conceptual and motor errors consolidate differently and interact with differences in practice style. [ABSTRACT FROM AUTHOR]

An integrated questionnaire was administered to a total of 4142 (2137 women, 2005 men; answer rate: 94.4%) university students and medical training schools students aged 18–40 years. The survey was carried out between May and October, 2004–2013. This questionnaire consisted of assessment of diurnal type, questions on sleep habits, mental health (upset emotionally, irritated, angered by small triggers, and suppressed), frequency of watching TV at night, use of mobile phone and playing TV games between 21:00 and 03:00 h, and questions on lighting conditions during the daytime and night. Sleep length in evening-type students (E-type; diurnal-type scores = 7–12) was shorter than in intermediate-types (I-type; diurnal-type scale (DTS) = 13–16) and morning-types (M-type; DTS = 17–28) on weekdays (p < 0.001), whereas sleep length in evening-types was shorter than intermediate- and morning-type students at weekends (p < 0.001). Mental health index scores of the E-type students were significantly lower than those of I-type and M-type students in both sexes (p < 0.001). Seventy-three percent of E-type women students watched TV after 23:00 h, significantly higher than 65.0 and 52.5% of I-type and M-type females, respectively (p < 0.001), and 70.4% of E-type male students watched the TV after 23:00 h, significantly higher than 66.1 and 59.7% of I-type and M-type males, respectively (p = 0.001). With regard to lighting conditions in the room in the afternoon, a slightly lower, but significantly so, percentage of the E-type students used the sunlight coming through the window than did the other types (p < 0.001). The frequency of having three nutritionally rich meals (especially breakfast) – including carbohydrates, proteins, vitamins, and minerals – was significantly higher in M-type than I-types and E-types (p < 0.001). Premenstrual syndrome (PMS) was significantly more severe in E-type than I-type and M-type females (p = 0.002). Lighting conditions throughout the 24 h and at breakfast can act as a strong zeitgeber for students and exert a great influence on their mental and physical health and can also affect PMS in women students. [ABSTRACT FROM AUTHOR]

Sleep is disrupted during active use of methamphetamine (MA), during withdrawal from the drug, and during abstinence from its use. However, relatively little is known about possible mediatory functions of disrupted sleep in the emergence, manifestation, and maintenance of cognitive and affective symptoms of MA abuse. We hypothesise that sleep functions as a mediator for stimulant drug effects. Specifically, we propose that objectively-measured sleep parameters can be used to explain some of the variability in the experience and presentation of memory deficits and emotion dysregulation in MA abusers. After describing how important healthy sleep is to unimpaired cognitive and affective functioning, we review literature describing how sleep is disrupted in MA abuse. Then, we provide a conceptual framework for our hypothesis by explaining the relationship between MA abuse, sleep disruption, memory deficits, emotion dysregulation, and changes in reward-related brain networks. We conclude by discussing implications of the hypothesis for research and treatment. [ABSTRACT FROM AUTHOR]

Electroencephalography (EEG) is typically viewed through the lens of spectral analysis. Recently, multiple lines of evidence have demonstrated that the underlying neuronal dynamics are characterized by scale-free avalanches. These results suggest that techniques from statistical physics may be used to analyze EEG signals. We utilized a publicly available database of fourteen subjects with waking and sleep stage 2 EEG tracings per subject, and observe that power-law dynamics of critical-state neuronal avalanches are not sufficient to fully describe essential features of EEG signals. We hypothesized that this could reflect the phenomenon of discrete scale invariance (DSI) in EEG large voltage deflections (LVDs) as being more prominent in waking consciousness. We isolated LVDs, and analyzed logarithmically transformed LVD size probability density functions (PDF) to assess for DSI. We find evidence of increased DSI in waking, as opposed to sleep stage 2 consciousness. We also show that the signatures of DSI are specific for EEG LVDs, and not a general feature of fractal simulations with similar statistical properties to EEG. Removing only LVDs from waking EEG produces a reduction in power in the alpha and beta frequency bands. These findings may represent a new insight into the understanding of the cortical dynamics underlying consciousness. [ABSTRACT FROM AUTHOR]

Individuals with Angelman syndrome (AS) suffer sleep disturbances that severely impair quality of life. Whether these disturbances arise from sleep or circadian clock dysfunction is currently unknown. Here, we explored the mechanistic basis for these sleep disorders in a mouse model of Angelman syndrome (Ube3am-/p+ mice). Genetic deletion of the maternal Ube3a allele practically eliminates UBE3A protein from the brain of Ube3am-/p+ mice, because the paternal allele is epigenetically silenced in most neurons. However, we found that UBE3A protein was present in many neurons of the suprachiasmatic nucleus-the site of the mammalian circadian clock−indicating that Ube3a can be expressed from both parental alleles in this brain region in adult mice. We found that while Ube3am-/p+ mice maintained relatively normal circadian rhythms of behavior and light-resetting, these mice exhibited consolidated locomotor activity and skipped the timed rest period (siesta) present in wild-type (Ube3am+/p+) mice. Electroencephalographic analysis revealed that alterations in sleep regulation were responsible for these overt changes in activity. Specifically, Ube3am-/p+ mice have a markedly reduced capacity to accumulate sleep pressure, both during their active period and in response to forced sleep deprivation. Thus, our data indicate that the siesta is governed by sleep pressure, and that Ube3a is an important regulator of sleep homeostasis. These preclinical findings suggest that therapeutic interventions that target mechanisms of sleep homeostasis may improve sleep quality in individuals with AS. [ABSTRACT FROM AUTHOR]

Sleep disturbances increase with increasing age in both males and females and become fairly common in the older community when compared to their younger counterparts. Even though these sleep disturbances increase with advancing age, there are nevertheless inherent differences in sleep disturbances between males and females. When compared to older men, older women will have a longer sleep latency (number of minutes it takes to fall asleep), more daytime sleepiness, will sleep about 20 min less per day, have less NREM stages 1 and 2 sleep, have more slow-wave sleep, and are more predisposed to REM sleep. Women have at least a 40% increased risk for developing insomnia, are at twice the risk for restless legs syndrome, will have different obstructive sleep apnea symptoms and more partial obstructions during sleep compared to men. They are also less likely to use antidepressants but will metabolize zolpidem 50% slower than men. [ABSTRACT FROM AUTHOR]

Goal: This paper presents a methodology for the automatic detection of sleep apnea from single-lead ECG. Methods: It uses two novel features derived from the ECG, and two well-known features in heart rate variability analysis, namely the standard deviation and the serial correlation coefficients of the RR interval time series. The first novel feature uses the principal components of the QRS complexes, and it describes changes in their morphology caused by an increased sympathetic activity during apnea. The second novel feature extracts the information shared between respiration and heart rate using orthogonal subspace projections. Respiratory information is derived from the ECG by means of three state-of-the-art algorithms, which are implemented and compared here. All features are used as input to a least-squares support vector machines classifier, using an RBF kernel. In total, 80 ECG recordings were included in the study. Results: Accuracies of about 85% are achieved on a minute-by-minute basis, for two independent datasets including both hypopneas and apneas together. Separation between apnea and normal recordings is achieved with 100% accuracy. In addition to apnea classification, the proposed methodology determines the contamination level of each ECG minute. Conclusion: The performances achieved are comparable with those reported in the literature for fully automated algorithms. Significance: These results indicate that the use of only ECG sensors can achieve good accuracies in the detection of sleep apnea. Moreover, the contamination level of each ECG segment can be used to automatically detect artefacts, and to highlight segments that require further visual inspection. [ABSTRACT FROM AUTHOR]

Sleep disorders are frequently reported in Alzheimer's disease (AD), with a significant impact on patients and caregivers and a major risk factor for early institutionalization. Although changes in sleep organization are a hallmark of the normal aging processes, sleep macro- and micro-architectural alterations are more evident in patients affected by AD. Degeneration of neural pathways regulating sleep-wake patterns and sleep architecture may contribute to sleep alterations. In return, several recent studies suggested that common sleep disorders may precede clinical symptoms of dementia and represent risk factors for cognitive decline, through impairment of sleep-dependent memory consolidation processes. Thus, a close relationship between sleep disorders and AD has been largely hypothesized. Here, sleep alterations in AD and its pre-dementia stage, mild cognitive impairment, and their complex interactions are reviewed. [ABSTRACT FROM AUTHOR]

Not only how good or bad people feel on average, but also how their feelings fluctuate across time is crucial for psychological health. The last 2 decades have witnessed a surge in research linking various patterns of short-term emotional change to adaptive or maladaptive psychological functioning, often with conflicting results. A meta-analysis was performed to identify consistent relationships between patterns of short-term emotion dynamics--including patterns reflecting emotional variability (measured in terms of within-person standard deviation of emotions across time), emotional instability (measured in terms of the magnitude of consecutive emotional changes), and emotional inertia of emotions over time (measured in terms of autocorrelation)--and relatively stable indicators of psychological well-being or psychopathology. We determined how such relationships are moderated by the type of emotional change, type of psychological well-being or psychopathology involved, valence of the emotion, and methodological factors. A total of 793 effect sizes were identified from 79 articles (N = 11,381) and were subjected to a 3-level meta-analysis. The results confirmed that overall, low psychological well-being co-occurs with more variable (overall ρ̂ = -.178), unstable (overall ρ̂ = -.205), but also more inert (overall ρ̂ = --.151) emotions. These effect sizes were stronger when involving negative compared with positive emotions. Moreover, the results provided evidence for consistency across different types of psychological well-being and psychopathology in their relation with these dynamical patterns, although specificity was also observed. The findings demonstrate that psychological flourishing is characterized by specific patterns of emotional fluctuations across time, and provide insight into what constitutes optimal and suboptimal emotional functioning. [ABSTRACT FROM AUTHOR]

It is widely believed that sleep is critical to the consolidation of learning and memory. In some skill domains, performance has been shown to improve by 20% or more following sleep, suggesting that sleep enhances learning. However, recent work suggests that those performance gains may be driven by several factors that are unrelated to sleep consolidation, inviting a reconsideration of sleep's theoretical role in the consolidation of procedural memories. Here we report the first comprehensive investigation of that possibility for the case of motor sequence learning. Quantitative meta-analyses involving 34 articles, 88 experimental groups and 1,296 subjects confirmed the empirical pattern of a large performance gain following sleep and a significantly smaller gain following wakefulness. However, the results also confirm strong moderating effects of 4 previously hypothesized variables: averaging in the calculation of prepost gain scores, build-up of reactive inhibition over training, time of testing, and training duration, along with 1 supplemental variable, elderly status. With those variables accounted for, there was no evidence that sleep enhances learning. Thus, the literature speaks against, rather than for. the enhancement hypothesis. Overall there was relatively better performance after sleep than after wakefulness, suggesting that sleep may stabilize memory. That effect, however, was not consistent across different experimental designs. We conclude that sleep does not enhance motor learning and that the role of sleep in the stabilization of memory cannot be conclusively determined based on the literature to date. We discuss challenges and opportunities for the field, make recommendations for improved experimental design, and suggest approaches to data analysis that eliminate confounds due to averaging over online learning. [ABSTRACT FROM AUTHOR]

Child and adolescent patients may display mental health concerns within some contexts and not others (e.g., home vs. school). Thus, understanding the specific contexts in which patients display concerns may assist mental health professionals in tailoring treatments to patients' needs. Consequently, clinical assessments often include reports from multiple informants who vary in the contexts in which they observe patients' behavior (e.g., patients, parents, teachers). Previous meta-analyses indicate that informants' reports correlate at low-to-moderate magnitudes. However, is it valid to interpret low correspondence among reports as indicating that patients display concerns in some contexts and not others? We meta-analyzed 341 studies published between 1989 and 2014 that reported cross-informant correspondence estimates, and observed low-to-moderate correspondence (mean internalizing: r = .25; mean externalizing: r = .30; mean overall: r = .28). Informant pair, mental health domain, and measurement method moderated magnitudes of correspondence. These robust findings have informed the development of concepts for interpreting multi-informant assessments, allowing researchers to draw specific predictions about the incremental and construct validity of these assessments. In turn, we critically evaluated research on the incremental and construct validity of the multi-informant approach to clinical child and adolescent assessment. In so doing, we identify crucial gaps in knowledge for future research, and provide recommendations for "best practices" in using and interpreting multi-informant assessments in clinical work and research. This article has important implications for developing personalized approaches to clinical assessment, with the goal of informing techniques for tailoring treatments to target the specific contexts where patients display concerns. [ABSTRACT FROM AUTHOR]

Learning and memory for extinction of conditioned fear is a basic mammalian mechanism for regulating negative emotion. Sleep promotes both the consolidation of memory and the regulation of emotion. Sleep can influence consolidation and modification of memories associated with both fear and its extinction. After brief overviews of the behavior and neural circuitry associated with fear conditioning, extinction learning, and extinction memory in the rodent and human, interactions of sleep with these processes will be examined. Animal and human studies suggest that sleep can serve to consolidate both fear and extinction memory. In humans, sleep also promotes generalization of extinction memory. Time-of-day effects on extinction learning and generalization are also seen. Rapid eye movement (REM) may be a sleep stage of particular importance for the consolidation of both fear and extinction memory as evidenced by selective REM deprivation experiments. REM sleep is accompanied by selective activation of the same limbic structures implicated in the learning and memory of fear and extinction. Preliminary evidence also suggests extinction learning can take place during slow wave sleep. Study of low-level processes such as conditioning, extinction, and habituation may allow sleep effects on emotional memory to be identified and inform study of sleep's effects on more complex, emotionally salient declarative memories. Anxiety disorders are marked by impairments of both sleep and extinction memory. Improving sleep quality may ameliorate anxiety disorders by strengthening naturally acquired extinction. Strategically timed sleep may be used to enhance treatment of anxiety by strengthening therapeutic extinction learned via exposure therapy. [ABSTRACT FROM AUTHOR]

The purpose of this work was to examine the relationships between geographical coordinates and the prevalence of winter depression ( SADW), and to compare the sleep characteristics and chronotype of youths with and without SADW. We conducted a cross-sectional study of self-reported sleep characteristics, chronotype and winter depression in northern European Russia. Two questionnaires, the Munich Chronotype Questionnaire ( MCTQ) and the Seasonal Pattern Assessment Questionnaire ( SPAQ), were administered to a total of 3435 adolescents aged 10-20 years (1517 males and 1918 females). The prevalence of SADW in the study population was 8.4% and sub- SADW 11.8%. Four variables predicted the likelihood of SADW in youths: sex [higher in females: odds ratio ( OR): 1.87, P < 0.0001], age (increases with age: OR: 1.09, P < 0.001), latitude (higher in the North: OR: 1.49, P < 0.029) and position in the time zone (higher in the West: OR: 1.61, P < 0.001). Later sleeping and waking, longer sleep latencies, more severe sleep inertia, shorter total sleep times and lower sleep efficiencies were observed in both males and females with SADW. The influence of SADW on sleep characteristics was more pronounced on school days. Significant phase delays of the sleep-wake rhythm and severe social jetlag (the difference between the mid-point of sleep phase at weekends and on workdays) were observed in females with SADW, but not in males. There are significant differences in sleep characteristics and chronotype between people with SADW and no- SAD. We demonstrate that both latitude of residence and location within the time zone are significant predictors of SADW in young inhabitants of the North. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effect of a total sleep deprivation (TSD) on the egocentric distance estimation following a fatiguing task (i.e. sprint repetitions). Ten soccer players (age: 22.8 ± 1.3 years; weight: 72. 8 ± 10 .5 kg; height: 1.8 ± 0.03 m) were volunteered to participate in the study. Subjects were invited to estimate different distances in two different sessions (i) following a reference night and (ii) following a night of TSD. The distance estimation consists to perceive three different distances (15, 25, and 35 m) before and after a repeated sprint exercise on a cycloergometer. The results demonstrated a significant effect of TSD on the perception of egocentric distance (F(1.9) = 11.22,p < 0.01). Indeed, the results showed an underestimation (compression of the real distance) of all distances at rest and following the repeated sprint exercise. Additionally, the underestimation was more acute after the fatiguing task. TSD affects the estimation of egocentric distance by soccer players at rest and following fatiguing task. [ABSTRACT FROM AUTHOR]

Background and purpose Cluster headache ( CH) is a primary headache disorder characterized by severe attacks of unilateral pain following a chronobiological pattern. There is a close connection with sleep as most attacks occur during sleep. Hypothalamic involvement and a particular association with rapid eye movement ( REM) sleep have been suggested. Sleep in a large, well-characterized population of CH patients was investigated. Methods Polysomnography ( PSG) was performed on two nights in 40 CH patients during active bout and one night in 25 age, sex and body mass index matched controls in hospital. Macrostructure and other features of sleep were analyzed and related to phenotype. Clinical headache characterization was obtained by semi-structured interview. Results Ninety-nine nights of PSG were analyzed. Findings included a reduced percentage of REM sleep (17.3% vs. 23.0%, P = 0.0037), longer REM latency (2.0 vs. 1.2 h, P = 0.0012) and fewer arousals (7.34 vs. 14.1, P = 0.003) in CH patients. There was no difference in prevalence of sleep apnea between patients (38%) and matched controls (32%, P = 0.64) although the apnea index in patients was numerically higher (mean apnea−hypopnea index 10.75 vs. 4.93). No temporal association between nocturnal attacks ( n = 45) and particular sleep stages was observed. Conclusions To date, this is the largest study of sleep in CH. It is demonstrated that REM sleep is affected which is in line with our current understanding of CH and hypothalamic involvement in the regulation of this sleep stage. Further, fewer arousals were found in CH patients but no association between apnea events or specific sleep stages. The findings support a central role of the hypothalamus and arousal systems in CH. [ABSTRACT FROM AUTHOR]

This study examined the differential associations between parent-reported child sleep problems in preschool and specific aspects of executive control in early elementary school in a large sample of typically developing children (N = 215). Consistent with expectations, sleep problems were negatively associated with performance on tasks assessing working memory and interference suppression inhibition, even after controlling for general cognitive abilities, but not with flexible shifting or response inhibition. The findings add to the literature on cognitive impairments associated with pediatric sleep loss and highlight the need for early intervention for children with sleep problems to promote healthy cognitive development. [ABSTRACT FROM AUTHOR]

This longitudinal study assessed the role of early sleep patterns in predicting attention regulation and behavior problems. Sleep of 43 infants was assessed using actigraphy at 12 months of age and then reassessed when the children were 3–4 years old. During this follow-up, their attention regulation and behavior problems were also assessed using a computerized test and parental reports. Lower quality of sleep in infancy significantly predicted compromised attention regulation and behavior problems. These findings underscore the need to identify and treat early sleep problems. [ABSTRACT FROM PUBLISHER]

This meta-analysis examined the effect experimental sleep restriction has on youth’s attention and hyperactivity outcomes. Thirteen published studies containing 17 independent samples were included (N= 496). Random- and fixed-effects models were used to estimate pooled effect sizes and moderator effects, respectively. Results indicate that sleep-restricted youth had significantly worse attention outcomes than youth with extended sleep, but no differences were evident regarding hyperactivity. Significant moderators of this effect included age and sex. These results have important implications for both the prevention and treatment of attention problems, highlighting the need for health professionals to screen for and treat underlying sleep issues. [ABSTRACT FROM PUBLISHER]

EEG, EMG, and EOG are very informative signals recorded in polysomnography (PSG) and used for sleep staging. Their reliable acquisition at home, however, is difficult. In comparison, ECG and thoracic respiratory (R) signals are easier to record and can be useful in home sleep monitoring systems. The simultaneous utilization of Heart Rate Variability (HRV) and respiratory (R) signals seems a plausible scenario as both heart rate (HR) and respiration rate (RR) vary during different sleep states. Therefore, we explored the combined discriminative capacity (accuracy, sensitivity, and specificity) of ECG/R signals in automatic sleep staging. As baseline, we classified the wakefulness, Stage 2, SWS (slow wave sleep) and REM sleep by using a Support Vector Machine (SVM) fed with a set of features extracted from: (a) HRV (34-features), (b) HRV/ECG-Derived Respiration (45-features), and (c) combined HRV/R (45-features) signals. Approach (a) produced reasonable discriminative capacity, while approach (b) significantly improved the classification; however, the best outcomes were achieved by using approach (c). Then, we enhanced the SVM classifier with the Recursive Feature Elimination (RFE) method. The classification results were improved with 35 out of the 45 HRV/RS-EDR features. In comparison, best results were obtained by combining 27 out of the 45 features derived from HRV/R signals, in which the optimal feature set selected by the SVM-RFE method, included a combination of time domain, time-frequency, and fractal features, as well as entropies. Overall, these improvements revealed that it is possible to simplify home monitoring of sleep disorders and achieve high discriminative capacity (accuracy = 89.32%, specificity = 92.88%, and sensitivity = 78.64%) in automatic sleep staging by the exclusive recording of cardiorespiratory signals. [ABSTRACT FROM AUTHOR]

The aim of the current study was to compare mental health problems, resilience and family characteristics in adolescents with and without delayed sleep phase ( DSP) in a population-based sample. Data were taken from the youth@hordaland-survey, a large population-based study in Hordaland County in Norway conducted in 2012. In all, 9338 adolescents aged 16-19 years (53.5% girls) provided self-reported data on a wide range of instruments assessing mental health symptoms, including depression, anxiety, obsessive-compulsive behaviours, attention deficit hyperactive disorder ( ADHD) symptoms, perfectionism, resilience and sleep. Measures of socioeconomic status were also included. Three hundred and six adolescents (prevalence 3.3%) were classified as having DSP [according to the International Classification of Sleep Disorders-2 ( ICSD-2)] criteria. Adolescents with DSP reported higher levels of depression, anxiety and ADHD symptoms. Adolescents with DSP also exhibited significantly lower levels of resilience. The Cohen's d effect sizes ranged from small [obsessive-compulsive disorder ( OCD): d = 0.15] to moderate (inattention: d = 0.71). In the fully adjusted model, the significant predictors of DSP included inattention [odds ratio ( OR): 2.11], lack of personal structure ( OR: 2.07), low ( OR: 1.85) and high ( OR: 1.91) paternal education, parents not living together ( OR: 1.81), hyperactivity/inattention (OR: 1.71) and poorer family economy ( OR: 1.59). In conclusion, the high symptom load across a range of mental health measures suggests that a broad and thorough clinical approach is warranted when adolescents present with DSP. [ABSTRACT FROM AUTHOR]

Those suffering insomnia symptoms generally report daytime impairments. However, research has not assessed whether this relationship holds on a nightly basis, despite the strongly held belief that a night of poor sleep impairs mood and functioning the following day. The objective of this study was to test this relationship in a group of older poor sleepers with insomnia symptoms compared with good sleepers. This study utilized a within-subjects design to investigate day-to-day subjective daytime functioning and its relation to the previous night's sleep. Seventeen older individuals (mean age: 67.5 years) were identified with a retrospective questionnaire and 2 weeks of sleep-wake diary to have poor sleep consistent with insomnia. Seventeen good sleepers (mean age: 67.8 years) were selected using the same measures. Participants reported their beliefs about sleep and daytime functioning on the Dysfunctional Beliefs and Attitudes about Sleep Scale ( DBAS-16). One week later they commenced a 14-day period of sleep-wake diaries and concurrent responses to a modified Daytime Insomnia Symptom Scale ( DISS). Results showed significant night-to-day covariation between sleep efficiency and daytime functioning for individuals with poor sleep ( r = 0.34), but not for good sleepers ( r = 0.08). Those poor sleepers who held this covariation belief most strongly were those who subsequently showed this night-to-day relationship the most strongly ( r = 0.56). This was not true for good sleepers. For those suffering insomnia, these findings demonstrate their belief that a poor sleep is followed by an impaired daytime, consistent with their experience. [ABSTRACT FROM AUTHOR]

The main purpose of the present analysis is to assess the influence of introducing early nasal continuous positive airway pressure ( nCPAP) treatment on cardiovascular recurrences and mortality in patients with a first-ever ischaemic stroke and moderate-severe obstructive sleep apnea (OSA) with an apnea-hypopnea index (AHI) ≥20 events h−1 during a 5-year follow-up. Patients received conventional treatment for stroke and were assigned randomly to the nCPAP group ( n = 71) or the control group ( n = 69). Cardiovascular events and mortality were registered for all patients. Survival and cardiovascular event-free survival analysis were performed after 5-year follow-up using the Kaplan-Meier test. Patients in the nCPAP group had significantly higher cardiovascular survival than the control group (100 versus 89.9%, log-rank test 5.887; P = 0.015) However, and also despite a positive tendency, there were no significant differences in the cardiovascular event-free survival at 68 months between the n CPAP and control groups (89.5 versus 75.4%, log-rank test 3.565; P = 0.059). Early n CPAP therapy has a positive effect on long-term survival in ischaemic stroke patients and moderate-severe OSA. [ABSTRACT FROM AUTHOR]