Pannexins Are Potential New Players in the Regulation of Cerebral Homeostasis during Sleep-Wake Cycle.

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Shestopalov, Valery I; Panchin, Yuri; Tarasova, Olga S; Gaynullina, Dina; Kovalzon, Vladimir M

2017-01-01

During brain homeostasis, both neurons and astroglia release ATP that is rapidly converted to adenosine in the extracellular space. Pannexin-1 (Panx1) hemichannels represent a major conduit of non-vesicular ATP release from brain cells. Previous studies have shown that Panx1 -/- mice possess severe disruption of the sleep-wake cycle. Here, we review experimental data supporting the involvement of pannexins (Panx) in the coordination of fundamental sleep-associated brain processes, such as neuronal activity and regulation of cerebrovascular tone. Panx1 hemichannels are likely implicated in the regulation of the sleep-wake cycle via an indirect effect of released ATP on adenosine receptors and through interaction with other somnogens, such as IL-1β, TNFα and prostaglandin D2. In addition to the recently established role of Panx1 in the regulation of endothelium-dependent arterial dilation, similar signaling pathways are the major cellular component of neurovascular coupling. The new discovered role of Panx in sleep regulation may have broad implications in coordinating neuronal activity and homeostatic housekeeping processes during the sleep-wake cycle.

Pannexins Are Potential New Players in the Regulation of Cerebral Homeostasis during Sleep-Wake Cycle

Directory of Open Access Journals (Sweden)

Valery I. Shestopalov

2017-07-01

Full Text Available During brain homeostasis, both neurons and astroglia release ATP that is rapidly converted to adenosine in the extracellular space. Pannexin-1 (Panx1 hemichannels represent a major conduit of non-vesicular ATP release from brain cells. Previous studies have shown that Panx1−/− mice possess severe disruption of the sleep-wake cycle. Here, we review experimental data supporting the involvement of pannexins (Panx in the coordination of fundamental sleep-associated brain processes, such as neuronal activity and regulation of cerebrovascular tone. Panx1 hemichannels are likely implicated in the regulation of the sleep-wake cycle via an indirect effect of released ATP on adenosine receptors and through interaction with other somnogens, such as IL-1β, TNFα and prostaglandin D2. In addition to the recently established role of Panx1 in the regulation of endothelium-dependent arterial dilation, similar signaling pathways are the major cellular component of neurovascular coupling. The new discovered role of Panx in sleep regulation may have broad implications in coordinating neuronal activity and homeostatic housekeeping processes during the sleep-wake cycle.

Regulation of Neuron-Astrocyte Metabolic Coupling across the Sleep-Wake Cycle

KAUST Repository

Petit, Jean-Marie; Magistretti, Pierre J.

2015-01-01

The aim of this review is to bring into perspective the role of astrocytes and neurometabolic coupling in the regulation of the sleep/wake cycle. The data reviewed also suggest an important role of the astrocytic network. In addition, the role of astrocytes in NMC mechanisms is consistent with the “local and use dependent” sleep hypothesis.

Eight weeks of citicoline treatment does not perturb sleep/wake cycles in cocaine-dependent adults.

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Bracken, Bethany K; Penetar, David M; Rodolico, John; Ryan, Elizabeth T; Lukas, Scott E

2011-06-01

Citicoline (cytidine-5'-diphosphate) is a mononucleotide composed of ribose, cytosine, pyrophosphate, and choline, and is involved in the biosynthesis of the structural phosopholipids of cell membranes. Treatment with citicoline, improves memory in patients with dementia, and reduces damage to the brain after traumatic brain injury or stroke. Recent research has been conducted to assess whether citicoline is an effective treatment for cocaine dependence. In cocaine-dependent individuals, withdrawal from cocaine is associated with disturbed sleep, which may contribute to the high rate of relapse to cocaine use. Therefore, it is important to know the impact of citicoline on the sleep/wake cycle in these individuals in order to rate its overall efficacy. In this double-blind, placebo-controlled trial, the effects of citicoline treatment on the sleep/wake cycles of cocaine dependent participants were assessed. The results of the current study are reported as part of a larger study, consisting of an eight-week treatment period to assess the efficacy of longer-term treatment with citicoline at decreasing cocaine consumption in cocaine-dependent polydrug using participants. In this non-abstinent, cocaine-dependent population, citicoline had no effect on any of the sleep parameters measured including sleep efficiency, sleep latency, total sleep time, number of waking episodes, time awake per episode, amount of time in bed spent moving, number of sleep episodes, time asleep per episode, and amount of time in bed spent immobile. These data suggest that eight weeks of citicoline administration does not disturb sleep/wake cycles of cocaine-dependent individuals. Copyright © 2011 Elsevier Inc. All rights reserved.

ECoG sleep-waking rhythms and bodily activity in the cerveau isolé rat.

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Nakata, K; Kawamura, H

1986-01-01

In rats with a high mesencephalic transection, isolating both the locus coeruleus and raphe nuclei from the forebrain, Electrocorticogram (ECoG) and Electromyogram (EMG) of the neck muscles were continuously recorded. Normal sleep-waking ECoG changes with a significant circadian rhythm reappeared in 4 to 9 days after transection. Neck muscle EMG and bodily movements were independent of the ECoG changes and did not show any significant circadian rhythm. In these high mesencephalic rats with sleep-waking ECoG changes, large bilateral hypothalamic lesions were made by passing DC current either in the preoptic area or in the posterior hypothalamus. After the preoptic area lesions the amount of low voltage fast ECoG per day markedly increased, whereas after the posterior hypothalamic lesions, the total amount of low voltate fast wave per day decreased showing long-lasting slow wave sleep pattern. These results support an idea that the forebrain, especially in the hypothalamus including the preoptic area, a mechanism inducing sleep-waking ECoG changes is localized.

On the functional significance of c-fos induction during the sleep-waking cycle.

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Cirelli, C; Tononi, G

2000-06-15

A striking finding in recent years has been that the transition from sleep to waking is accompanied in many brain regions by a widespread activation of c-fos and other immediate-early genes (IEGs). IEGs are induced by various electrical or chemical signals to which neural cells are exposed and their protein products act as transcription factors to regulate the expression of other genes. After a few hours of sleep, the expression of these transcription factors in the brain is absent or restricted to very few cells. However, after a few hours of spontaneous waking or sleep deprivation, the expression of c-fos and other IEGs is high in cerebral cortex, hypothalamus, septum, and several thalamic and brainstem nuclei. While cells expressing c-fos during waking are widely distributed, they represent only a subset of all neurons in any given area. These observations raise several questions: Why is c-fos expressed during waking and not during sleep? Is waking always accompanied by c-fos induction? Which subset of cells express c-fos during waking and why only a subset? Once c-fos has been induced, what are the functional consequences of its activation? In this review, we summarize our current understanding of the meaning of c-fos activation in the brain in relation to the sleep-waking cycle and suggest that c-fos induction in the cerebral cortex during waking might be related to the occurrence of plastic phenomena.

Functional anatomy of the sleep-wakefulness cycle: wakefulness.

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Reinoso-Suárez, Fernando; de Andrés, Isabel; Garzón, Miguel

2011-01-01

Sleep is a necessary, diverse, periodic, and an active condition circadian and homeostatically regulated and precisely meshed with waking time into the sleep-wakefulness cycle (SWC). Photic retinal stimulation modulates the suprachiasmatic nucleus, which acts as the pacemaker for SWC rhythmicity. Both the light period and social cues adjust the internal clock, making the SWC a circadian, 24-h period in the adult human. Bioelectrical and behavioral parameters characterize the different phases of the SWC. For a long time, lesions and electrical stimulation of brain structures, as well as connection studies, were the main methods used to decipher the foundations of the functional anatomy of the SWC. That is why the first section of this review presents these early historical studies to then discuss the current state of our knowledge based on our understanding of the functional anatomy of the structures underlying the SWC. Supported by this description, we then present a detailed review and update of the structures involved in the phase of wakefulness (W), including their morphological, functional, and chemical characteristics, as well as their anatomical connections. The structures for W generation are known as the "ascending reticular activating system", and they keep and maintain the "thalamo-cerebral cortex unit" awake. This system originates from the neuronal groups located within the brainstem, hypothalamus, and basal forebrain, which use known neurotransmitters and whose neurons are more active during W than during the other SWC states. Thus, synergies among several of these neurotransmitters are necessary to generate the cortical and thalamic activation that is characteristic of the W state, with all the plastic qualities and nuances present in its different behavioral circumstances. Each one of the neurotransmitters exerts powerful influences on the information and cognitive processes as well as attentional, emotional, motivational, behavioral, and arousal

Disorders of the Sleep-Wake Cycle in Blindness | Odeo | West ...

African Journals Online (AJOL)

BACKGROUND: Alteration of the intensity of light reaching the pineal gland through the visual pathway affects the sleepwake cycle in humans. OBJECTIVE: To determine the prevalence, types and severity of sleep-wake disorders in the blind and their relation to the degree and cause of blindness. METHODS: One hundred ...

Sleep/Wake Physiology and Quantitative Electroencephalogram Analysis of the Neuroligin-3 Knockout Rat Model of Autism Spectrum Disorder.

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Thomas, Alexia M; Schwartz, Michael D; Saxe, Michael D; Kilduff, Thomas S

2017-10-01

Neuroligin-3 (NLGN3) is one of the many genes associated with autism spectrum disorder (ASD). Sleep dysfunction is highly prevalent in ASD, but has not been rigorously examined in ASD models. Here, we evaluated sleep/wake physiology and behavioral phenotypes of rats with genetic ablation of Nlgn3. Male Nlgn3 knockout (KO) and wild-type (WT) rats were assessed using a test battery for ASD-related behaviors and also implanted with telemeters to record the electroencephalogram (EEG), electromyogram, body temperature, and locomotor activity. 24-h EEG recordings were analyzed for sleep/wake states and spectral composition. Nlgn3 KO rats were hyperactive, exhibited excessive chewing behavior, and had impaired prepulse inhibition to an auditory startle stimulus. KO rats also spent less time in non-rapid eye movement (NREM) sleep, more time in rapid eye movement (REM) sleep, exhibited elevated theta power (4-9 Hz) during wakefulness and REM, and elevated delta power (0.5-4 Hz) during NREM. Beta (12-30 Hz) power and gamma (30-50 Hz) power were suppressed across all vigilance states. The sleep disruptions in Nlgn3 KO rats are consistent with observations of sleep disturbances in ASD patients. The EEG provides objective measures of brain function to complement rodent behavioral analyses and therefore may be a useful tool to study ASD. © 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.

Spike avalanches exhibit universal dynamics across the sleep-wake cycle.

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Tiago L Ribeiro

2010-11-01

Full Text Available Scale-invariant neuronal avalanches have been observed in cell cultures and slices as well as anesthetized and awake brains, suggesting that the brain operates near criticality, i.e. within a narrow margin between avalanche propagation and extinction. In theory, criticality provides many desirable features for the behaving brain, optimizing computational capabilities, information transmission, sensitivity to sensory stimuli and size of memory repertoires. However, a thorough characterization of neuronal avalanches in freely-behaving (FB animals is still missing, thus raising doubts about their relevance for brain function.To address this issue, we employed chronically implanted multielectrode arrays (MEA to record avalanches of action potentials (spikes from the cerebral cortex and hippocampus of 14 rats, as they spontaneously traversed the wake-sleep cycle, explored novel objects or were subjected to anesthesia (AN. We then modeled spike avalanches to evaluate the impact of sparse MEA sampling on their statistics. We found that the size distribution of spike avalanches are well fit by lognormal distributions in FB animals, and by truncated power laws in the AN group. FB data surrogation markedly decreases the tail of the distribution, i.e. spike shuffling destroys the largest avalanches. The FB data are also characterized by multiple key features compatible with criticality in the temporal domain, such as 1/f spectra and long-term correlations as measured by detrended fluctuation analysis. These signatures are very stable across waking, slow-wave sleep and rapid-eye-movement sleep, but collapse during anesthesia. Likewise, waiting time distributions obey a single scaling function during all natural behavioral states, but not during anesthesia. Results are equivalent for neuronal ensembles recorded from visual and tactile areas of the cerebral cortex, as well as the hippocampus.Altogether, the data provide a comprehensive link between behavior

High-frequency oscillations in human and monkey neocortex during the wake-sleep cycle.

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Le Van Quyen, Michel; Muller, Lyle E; Telenczuk, Bartosz; Halgren, Eric; Cash, Sydney; Hatsopoulos, Nicholas G; Dehghani, Nima; Destexhe, Alain

2016-08-16

Beta (β)- and gamma (γ)-oscillations are present in different cortical areas and are thought to be inhibition-driven, but it is not known if these properties also apply to γ-oscillations in humans. Here, we analyze such oscillations in high-density microelectrode array recordings in human and monkey during the wake-sleep cycle. In these recordings, units were classified as excitatory and inhibitory cells. We find that γ-oscillations in human and β-oscillations in monkey are characterized by a strong implication of inhibitory neurons, both in terms of their firing rate and their phasic firing with the oscillation cycle. The β- and γ-waves systematically propagate across the array, with similar velocities, during both wake and sleep. However, only in slow-wave sleep (SWS) β- and γ-oscillations are associated with highly coherent and functional interactions across several millimeters of the neocortex. This interaction is specifically pronounced between inhibitory cells. These results suggest that inhibitory cells are dominantly involved in the genesis of β- and γ-oscillations, as well as in the organization of their large-scale coherence in the awake and sleeping brain. The highest oscillation coherence found during SWS suggests that fast oscillations implement a highly coherent reactivation of wake patterns that may support memory consolidation during SWS.

Role of N-Arachidonoyl-Serotonin (AA-5-HT in Sleep-Wake Cycle Architecture, Sleep Homeostasis, and Neurotransmitters Regulation

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Eric Murillo-Rodríguez

2017-05-01

Full Text Available The endocannabinoid system comprises several molecular entities such as endogenous ligands [anandamide (AEA and 2-arachidonoylglycerol (2-AG], receptors (CB1 and CB2, enzymes such as [fatty acid amide hydrolase (FAHH and monoacylglycerol lipase (MAGL], as well as the anandamide membrane transporter. Although the role of this complex neurobiological system in the sleep–wake cycle modulation has been studied, the contribution of the blocker of FAAH/transient receptor potential cation channel subfamily V member 1 (TRPV1, N-arachidonoyl-serotonin (AA-5-HT in sleep has not been investigated. Thus, in the present study, varying doses of AA-5-HT (5, 10, or 20 mg/Kg, i.p. injected at the beginning of the lights-on period of rats, caused no statistical changes in sleep patterns. However, similar pharmacological treatment given to animals at the beginning of the dark period decreased wakefulness (W and increased slow wave sleep (SWS as well as rapid eye movement sleep (REMS. Power spectra analysis of states of vigilance showed that injection of AA-5-HT during the lights-off period diminished alpha spectrum across alertness in a dose-dependent fashion. In opposition, delta power spectra was enhanced as well as theta spectrum, during SWS and REMS, respectively. Moreover, the highest dose of AA-5-HT decreased wake-related contents of neurotransmitters such as dopamine (DA, norepinephrine (NE, epinephrine (EP, serotonin (5-HT whereas the levels of adenosine (AD were enhanced. In addition, the sleep-inducing properties of AA-5-HT were confirmed since this compound blocked the increase in W caused by stimulants such as cannabidiol (CBD or modafinil (MOD during the lights-on period. Additionally, administration of AA-5-HT also prevented the enhancement in contents of DA, NE, EP, 5-HT and AD after CBD of MOD injection. Lastly, the role of AA-5-HT in sleep homeostasis was tested in animals that received either CBD or MOD after total sleep deprivation (TSD. The

Influence of serial electrical stimulations of perifornical and posterior hypothalamic orexin-containing neurons on regulation of sleep homeostasis and sleep-wakefulness cycle recovery from experimental comatose state and anesthesia-induced deep sleep.

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Chijavadze, E; Chkhartishvili, E; Babilodze, M; Maglakelidze, N; Nachkebia, N

2013-11-01

The work was aimed for the ascertainment of following question - whether Orexin-containing neurons of dorsal and lateral hypothalamic, and brain Orexinergic system in general, are those cellular targets which can speed up recovery of disturbed sleep homeostasis and accelerate restoration of sleep-wakefulness cycle phases during some pathological conditions - experimental comatose state and/or deep anesthesia-induced sleep. Study was carried out on white rats. Modeling of experimental comatose state was made by midbrain cytotoxic lesions at intra-collicular level.Animals were under artificial respiration and special care. Different doses of Sodium Ethaminal were used for deep anesthesia. 30 min after comatose state and/or deep anesthesia induced sleep serial electrical stimulations of posterior and/or perifornical hypothalamus were started. Stimulation period lasted for 1 hour with the 5 min intervals between subsequent stimulations applied by turn to the left and right side hypothalamic parts.EEG registration of cortical and hippocampal electrical activity was started immediately after experimental comatose state and deep anesthesia induced sleep and continued continuously during 72 hour. According to obtained new evidences, serial electrical stimulations of posterior and perifornical hypothalamic Orexin-containing neurons significantly accelerate recovery of sleep homeostasis, disturbed because of comatose state and/or deep anesthesia induced sleep. Speed up recovery of sleep homeostasis was manifested in acceleration of coming out from comatose state and deep anesthesia induced sleep and significant early restoration of sleep-wakefulness cycle behavioral states.

Sleep-Wake Actigraphy and Light Exposure During Spaceflight-Long

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Czeisler, Charles A.; Barger, Laura K.; Wright, Kenneth P., Jr.; Ronda, Joseph

2009-01-01

Sleep-Wake Actigraphy and Light Exposure During Spaceflight-Long (Sleep-Long) will examine the effects of spaceflight and ambient light exposure on the sleep-wake cycles of the crew members during long-duration stays on the space station.

Sleep-wake cycle of adolescents in Côte d'Ivoire: influence of age, gender, religion and occupation.

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Borchers, Claudia; Randler, Christoph

2012-12-01

The human sleep-wake cycle is characterized by significant individual differences. Those differences in the sleep-wake cycle are partially heritable but are also influenced by environmental factors like the light/dark cycle or social habits. In this study we analyse for the first time the sleep-wake rhythm of adolescent pupils and working adolescents in a less industrialised country in West Africa near the equator. The aim of this study was to explore the sleep wake cycle in this geographical region, using Côte d'Ivoire as an example. Data collection took place between 2nd of March and 10th of June 2009. 588 adolescents (338 girls, 250 boys) between 10 and 15 years (mean ± SD: 12.72 ± 1.63) participated in this study. We collected data on the religion of the participants (Christian (N = 159), Muslim (N = 352), other/no religion (N = 77)) and their occupation. Participants were either pupils attending school (N = 336) or adolescents that were already working (N = 252) and not attending school. The interviewer filled in the questionnaire. We found significant effects of age (p gender (p religion (p < 0.001) and region (p < 0.001). The midpoint of sleep was on average 1:26 (SD: 00:30) on weekdays and 1:37 (SD: 00:42) on weekend days. There are significant differences between weekdays and weekend days, but these were only small. Sleep duration suggests that adolescents in Côte d'Ivoire may gain sufficient sleep during week and weekend days, and thus, may live more in accordance with their own biological clock than adolescents in the northern hemisphere. In contrast, the data can be interpreted that adolescents live in a permanent 'jetlag'. Factors may be the more continuous light/dark cycle in the tropics, low amount of ambient light and less electricity.

Sleep-wake cycle phenotypes in young people with familial and non-familial mood disorders.

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Scott, Jan; Naismith, Sharon; Grierson, Ashlee; Carpenter, Joanne; Hermens, Daniel; Scott, Elizabeth; Hickie, Ian

2016-12-01

Converging evidence identifies that the offspring of parents with bipolar disorder (BD), individuals at clinical high risk of BD, and young people with recent onset BD may differ from other clinical cases or healthy controls in terms of sleep-wake profiles. However, it is possible that these differences may reflect current mental state, subtype of mood disorder, or familial traits. This study aimed to determine objective and subjective sleep-wake profiles in individuals aged 15-25 years with a current major depressive episode, in relation to familial traits. Frequency matching was employed to ensure that each individual with a confirmed family history of BD (FH+) could be compared to four controls who did not have a familial mood disorder (FH-). Pre-selected objective actigraphy and subjective Pittsburgh Sleep Quality Index (PSQI) ratings were compared using one-way analysis of variance (ANOVA) and applying the Benjamini-Hochberg (BH) correction for false discoveries. The sample comprised 60 individuals with a mean age of 19 years. The FH+ (n=12) and FH- groups (n=48) differed on three key sleep parameters: mean sleep duration on week nights (P=.049), variability in waking after sleep onset (P=.038), and daily disturbances (PSQI dimension of sleep disturbance and daytime dysfunction; P=.01). The sleep profiles we identified in this study, especially the daily disturbances phenotype, provide support for research into endophenotypes for BD. Also, the findings may offer the opportunity for more tailored, personalized interventions that target specific components of the sleep-wake cycle in individuals with a family history of BD. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Optogenetic deconstruction of sleep-wake circuitry in the brain

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Antoine Adamantidis

2010-01-01

Full Text Available How does the brain regulate the sleep-wake cycle? What are the temporal codes of sleep- and wake-promoting neural circuits? How do these circuits interact with each other across the light/dark cycle? Over the past few decades, many studies from a variety of disciplines have made substantial progress in answering these fundamental questions. For example, neurobiologists have identified multiple, redundant wake-promoting circuits in the brainstem, hypothalamus, and basal forebrain. Sleep-promoting circuits have been found in the preoptic area and hypothalamus. One of the greatest challenges in recent years has been to selectively record and manipulate these sleep-wake centers in vivo with high spatial and temporal resolution. Recent developments in microbial opsin-based neuromodulation tools, collectively referred to as “optogenetics,” have provided a novel method to demonstrate causal links between neural activity and specific behaviors. Here, we propose to use optogenetics as a fundamental tool to probe the necessity, sufficiency, and connectivity of defined neural circuits in the regulation of sleep and wakefulness.

Tunable locally-optimal geographical forwarding in wireless sensor networks with sleep-wake cycling nodes

OpenAIRE

Naveen, K. P.; Kumar, A.

2009-01-01

We consider a wireless sensor network whose main function is to detect certain infrequent alarm events, and to forward alarm packets to a base station, using geographical forwarding. The nodes know their locations, and they sleep-wake cycle, waking up periodically but not synchronously. In this situation, when a node has a packet to forward to the sink, there is a trade-off between how long this node waits for a suitable neighbor to wake up and the progress the packet makes towards the sink o...

Arvicanthis ansorgei, a Novel Model for the Study of Sleep and Waking in Diurnal Rodents

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Hubbard, Jeffrey; Ruppert, Elisabeth; Calvel, Laurent; Robin-Choteau, Ludivine; Gropp, Claire-Marie; Allemann, Caroline; Reibel, Sophie; Sage-Ciocca, Dominique; Bourgin, Patrice

2015-01-01

Study Objectives: Sleep neurobiology studies use nocturnal species, mainly rats and mice. However, because their daily sleep/wake organization is inverted as compared to humans, a diurnal model for sleep studies is needed. To fill this gap, we phenotyped sleep and waking in Arvicanthis ansorgei, a diurnal rodent widely used for the study of circadian rhythms. Design: Video-electroencephalogram (EEG), electromyogram (EMG), and electrooculogram (EOG) recordings. Setting: Rodent sleep laboratory. Participants: Fourteen male Arvicanthis ansorgei, aged 3 mo. Interventions: 12 h light (L):12 h dark (D) baseline condition, 24-h constant darkness, 6-h sleep deprivation. Measurements and Results: Wake and rapid eye movement (REM) sleep showed similar electrophysiological characteristics as nocturnal rodents. On average, animals spent 12.9 h ± 0.4 awake per 24-h cycle, of which 6.88 h ± 0.3 was during the light period. NREM sleep accounted for 9.63 h ± 0.4, which of 5.13 h ± 0.2 during dark period, and REM sleep for 89.9 min ± 6.7, which of 52.8 min ± 4.4 during dark period. The time-course of sleep and waking across the 12 h light:12 h dark was overall inverted to that observed in rats or mice, though with larger amounts of crepuscular activity at light and dark transitions. A dominant crepuscular regulation of sleep and waking persisted under constant darkness, showing the lack of a strong circadian drive in the absence of clock reinforcement by external cues, such as a running wheel. Conservation of the homeostatic regulation was confirmed with the observation of higher delta power following sustained waking periods and a 6-h sleep deprivation, with subsequent decrease during recovery sleep. Conclusions: Arvicanthis ansorgei is a valid diurnal rodent model for studying the regulatory mechanisms of sleep and so represents a valuable tool for further understanding the nocturnality/diurnality switch. Citation: Hubbard J, Ruppert E, Calvel L, Robin-Choteau L, Gropp CM

Sleep wake pattern analysis: Study of 131 medical students

OpenAIRE

Nita Ninama; Jaydeep Kangathara

2012-01-01

Objective:Sleep is part of the rhythm of life. Without a good sleep the mind is less adapts, mood is altered and the body loses the ability to refresh. The sleep wake cycle of the students is quite different and characterized by delayed onset, partial sleep deprivation, poor sleep quality, insufficient sleep duration and occurrence of napping episodes during the day The aim of the present study is to know sleep wake pattern in medical student, role of residence and individual characterization...

Improved circadian sleep-wake cycle in infants fed a day/night dissociated formula milk.

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Cubero, J; Narciso, D; Aparicio, S; Garau, C; Valero, V; Rivero, M; Esteban, S; Rial, R; Rodríguez, A B; Barriga, C

2006-06-01

On the basis of the circadian nutritional variations present in breast milk, and of the implications for the sleep/wake cycle of the nutrients present in infant formula milks, we designed a formula milk nutritionally dissociated into a Day/Night composition. The goal was to improve the bottle-fed infant's sleep/wake circadian rhythm. A total of 21 infants aged 4-20 weeks with sleeping difficulties were enrolled in the three-week duration study. The sleep analysis was performed using an actimeter (Actiwatch) placed on an ankle of each infant to uninterruptedly record movements during the three weeks. The dissociated Day milk, designed to be administered from 06:00 to 18:00, contained low levels of tryptophan (1.5g/100g protein) and carbohydrates, high levels of proteins, and the nucleotides Cytidine 5 monophosphate, Guanosine 5 monophosphate and Inosine 5 monophosphate. The dissociated Night milk, designed to be administered from 18.00 to 06.00, contained high levels of tryptophan (3.4g/100g protein) and carbohydrates, low levels of protein, and the nucleotides Adenosine 5 monophosphate and Uridine 5 monophosphate. Three different milk-feeding experiments were performed in a double-blind procedure covering three weeks. In week 1 (control), the infants received both by day and by night a standard formula milk; in week 2 (inverse control), they received the dissociated milk inversely (Night/Day instead of Day/Night); and in week 3, they received the Day/Night dissociated formula concordant with the formula design. When the infants were receiving the Day/Night dissociated milk in concordance with their environment, they showed improvement in all the nocturnal sleep parameters analyzed: total hours of sleep, sleep efficiency, minutes of nocturnal immobility, nocturnal awakenings, and sleep latency. In conclusion, the use of a chronobiologically adjusted infant formula milk seems to be effective in improving the consolidation of the circadian sleep/wake cycle in bottle

Role of the locus coeruleus in the emergence of power law wake bouts in a model of the brainstem sleep-wake system through early infancy.

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Patel, Mainak; Rangan, Aaditya

2017-08-07

Infant rats randomly cycle between the sleeping and waking states, which are tightly correlated with the activity of mutually inhibitory brainstem sleep and wake populations. Bouts of sleep and wakefulness are random; from P2-P10, sleep and wake bout lengths are exponentially distributed with increasing means, while during P10-P21, the sleep bout distribution remains exponential while the distribution of wake bouts gradually transforms to power law. The locus coeruleus (LC), via an undeciphered interaction with sleep and wake populations, has been shown experimentally to be responsible for the exponential to power law transition. Concurrently during P10-P21, the LC undergoes striking physiological changes - the LC exhibits strong global 0.3 Hz oscillations up to P10, but the oscillation frequency gradually rises and synchrony diminishes from P10-P21, with oscillations and synchrony vanishing at P21 and beyond. In this work, we construct a biologically plausible Wilson Cowan-style model consisting of the LC along with sleep and wake populations. We show that external noise and strong reciprocal inhibition can lead to switching between sleep and wake populations and exponentially distributed sleep and wake bout durations as during P2-P10, with the parameters of inhibition between the sleep and wake populations controlling mean bout lengths. Furthermore, we show that the changing physiology of the LC from P10-P21, coupled with reciprocal excitation between the LC and wake population, can explain the shift from exponential to power law of the wake bout distribution. To our knowledge, this is the first study that proposes a plausible biological mechanism, which incorporates the known changing physiology of the LC, for tying the developing sleep-wake circuit and its interaction with the LC to the transformation of sleep and wake bout dynamics from P2-P21. Copyright © 2017 Elsevier Ltd. All rights reserved.

Spontaneous sleep-wake cycle and sleep deprivation differently induce Bdnf1, Bdnf4 and Bdnf9a DNA methylation and transcripts levels in the basal forebrain and frontal cortex in rats.

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Ventskovska, Olena; Porkka-Heiskanen, Tarja; Karpova, Nina N

2015-04-01

Brain-derived neurotrophic factor (Bdnf) regulates neuronal plasticity, slow wave activity and sleep homeostasis. Environmental stimuli control Bdnf expression through epigenetic mechanisms, but there are no data on epigenetic regulation of Bdnf by sleep or sleep deprivation. Here we investigated whether 5-methylcytosine (5mC) DNA modification at Bdnf promoters p1, p4 and p9 influences Bdnf1, Bdnf4 and Bdnf9a expression during the normal inactive phase or after sleep deprivation (SD) (3, 6 and 12 h, end-times being ZT3, ZT6 and ZT12) in rats in two brain areas involved in sleep regulation, the basal forebrain and cortex. We found a daytime variation in cortical Bdnf expression: Bdnf1 expression was highest at ZT6 and Bdnf4 lowest at ZT12. Such variation was not observed in the basal forebrain. Also Bdnf p1 and p9 methylation levels differed only in the cortex, while Bdnf p4 methylation did not vary in either area. Factorial analysis revealed that sleep deprivation significantly induced Bdnf1 and Bdnf4 with the similar pattern for Bdnf9a in both basal forebrain and cortex; 12 h of sleep deprivation decreased 5mC levels at the cortical Bdnf p4 and p9. Regression analysis between the 5mC promoter levels and the corresponding Bdnf transcript expression revealed significant negative correlations for the basal forebrain Bdnf1 and cortical Bdnf9a transcripts in only non-deprived rats, while these correlations were lost after sleep deprivation. Our results suggest that Bdnf transcription during the light phase of undisturbed sleep-wake cycle but not after SD is regulated at least partially by brain site-specific DNA methylation. © 2014 European Sleep Research Society.

Circadian Rhythm Sleep-Wake Disorders.

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Abbott, Sabra M; Reid, Kathryn J; Zee, Phyllis C

2015-12-01

The circadian system regulates the timing and expression of nearly all biological processes, most notably, the sleep-wake cycle, and disruption of this system can result in adverse effects on both physical and mental health. The circadian rhythm sleep-wake disorders (CRSWDs) consist of 5 disorders that are due primarily to pathology of the circadian clock or to a misalignment of the timing of the endogenous circadian rhythm with the environment. This article outlines the nature of these disorders, the association of many of these disorders with psychiatric illness, and available treatment options. Copyright © 2015 Elsevier Inc. All rights reserved.

Extracellular levels of lactate, but not oxygen, reflect sleep homeostasis in the rat cerebral cortex.

Science.gov (United States)

Dash, Michael B; Tononi, Giulio; Cirelli, Chiara

2012-07-01

It is well established that brain metabolism is higher during wake and rapid eye movement (REM) sleep than in nonrapid eye movement (NREM) sleep. Most of the brain's energy is used to maintain neuronal firing and glutamatergic transmission. Recent evidence shows that cortical firing rates, extracellular glutamate levels, and markers of excitatory synaptic strength increase with time spent awake and decline throughout NREM sleep. These data imply that the metabolic cost of each behavioral state is not fixed but may reflect sleep-wake history, a possibility that is investigated in the current report. Chronic (4d) electroencephalographic (EEG) recordings in the rat cerebral cortex were coupled with fixed-potential amperometry to monitor the extracellular concentration of oxygen ([oxy]) and lactate ([lac]) on a second-by-second basis across the spontaneous sleep-wake cycle and in response to sleep deprivation. Basic sleep research laboratory. Wistar Kyoto (WKY) adult male rats. N/A. Within 30-60 sec [lac] and [oxy] progressively increased during wake and REM sleep and declined during NREM sleep (n = 10 rats/metabolite), but with several differences. [Oxy], but not [lac], increased more during wake with high motor activity and/or elevated EEG high-frequency power. Meanwhile, only the NREM decline of [lac] reflected sleep pressure as measured by slow-wave activity, mirroring previous results for cortical glutamate. The observed state-dependent changes in cortical [lac] and [oxy] are consistent with higher brain metabolism during waking and REM sleep in comparison with NREM sleep. Moreover, these data suggest that glycolytic activity, most likely through its link with glutamatergic transmission, reflects sleep homeostasis.

Expression of interferon-inducible chemokines and sleep/wake changes during early encephalitis in experimental African trypanosomiasis.

Science.gov (United States)

Laperchia, Claudia; Tesoriero, Chiara; Seke-Etet, Paul F; La Verde, Valentina; Colavito, Valeria; Grassi-Zucconi, Gigliola; Rodgers, Jean; Montague, Paul; Kennedy, Peter G E; Bentivoglio, Marina

2017-08-01

Human African trypanosomiasis or sleeping sickness, caused by the parasite Trypanosoma brucei, leads to neuroinflammation and characteristic sleep/wake alterations. The relationship between the onset of these alterations and the development of neuroinflammation is of high translational relevance, but remains unclear. This study investigates the expression of interferon (IFN)-γ and IFN-inducible chemokine genes in the brain, and the levels of CXCL10 in the serum and cerebrospinal fluid prior to and during the encephalitic stage of trypanosome infection, and correlates these with sleep/wake changes in a rat model of the disease. The expression of genes encoding IFN-γ, CXCL9, CXCL10, and CXCL11 was assessed in the brain of rats infected with Trypanosoma brucei brucei and matched controls using semi-quantitative end-point RT-PCR. Levels of CXCL10 in the serum and cerebrospinal fluid were determined using ELISA. Sleep/wake states were monitored by telemetric recording. Using immunohistochemistry, parasites were found in the brain parenchyma at 14 days post-infection (dpi), but not at 6 dpi. Ifn-γ, Cxcl9, Cxcl10 and Cxcl11 mRNA levels showed moderate upregulation by 14 dpi followed by further increase between 14 and 21 dpi. CXCL10 concentration in the cerebrospinal fluid increased between 14 and 21 dpi, preceded by a rise in the serum CXCL10 level between 6 and 14 dpi. Sleep/wake pattern fragmentation was evident at 14 dpi, especially in the phase of wake predominance, with intrusion of sleep episodes into wakefulness. The results show a modest increase in Cxcl9 and Cxcl11 transcripts in the brain and the emergence of sleep/wake cycle fragmentation in the initial encephalitic stage, followed by increases in Ifn-γ and IFN-dependent chemokine transcripts in the brain and of CXCL10 in the cerebrospinal fluid. The latter parameter and sleep/wake alterations could provide combined humoral and functional biomarkers of the early encephalitic stage in African trypanosomiasis.

Expression of interferon-inducible chemokines and sleep/wake changes during early encephalitis in experimental African trypanosomiasis.

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Claudia Laperchia

2017-08-01

Full Text Available Human African trypanosomiasis or sleeping sickness, caused by the parasite Trypanosoma brucei, leads to neuroinflammation and characteristic sleep/wake alterations. The relationship between the onset of these alterations and the development of neuroinflammation is of high translational relevance, but remains unclear. This study investigates the expression of interferon (IFN-γ and IFN-inducible chemokine genes in the brain, and the levels of CXCL10 in the serum and cerebrospinal fluid prior to and during the encephalitic stage of trypanosome infection, and correlates these with sleep/wake changes in a rat model of the disease.The expression of genes encoding IFN-γ, CXCL9, CXCL10, and CXCL11 was assessed in the brain of rats infected with Trypanosoma brucei brucei and matched controls using semi-quantitative end-point RT-PCR. Levels of CXCL10 in the serum and cerebrospinal fluid were determined using ELISA. Sleep/wake states were monitored by telemetric recording. Using immunohistochemistry, parasites were found in the brain parenchyma at 14 days post-infection (dpi, but not at 6 dpi. Ifn-γ, Cxcl9, Cxcl10 and Cxcl11 mRNA levels showed moderate upregulation by 14 dpi followed by further increase between 14 and 21 dpi. CXCL10 concentration in the cerebrospinal fluid increased between 14 and 21 dpi, preceded by a rise in the serum CXCL10 level between 6 and 14 dpi. Sleep/wake pattern fragmentation was evident at 14 dpi, especially in the phase of wake predominance, with intrusion of sleep episodes into wakefulness.The results show a modest increase in Cxcl9 and Cxcl11 transcripts in the brain and the emergence of sleep/wake cycle fragmentation in the initial encephalitic stage, followed by increases in Ifn-γ and IFN-dependent chemokine transcripts in the brain and of CXCL10 in the cerebrospinal fluid. The latter parameter and sleep/wake alterations could provide combined humoral and functional biomarkers of the early encephalitic stage in African

Differential effects of midazolam and zolpidem on sleep-wake states and epileptic activity in WAG/Rij rats

NARCIS (Netherlands)

Depoortere, H.; Francon, D.; Luijtelaar, E.L.J.M. van; Drinkenburg, W.H.I.M.; Coenen, A.M.L.

1995-01-01

Hypnotic drugs are known to possess antiepileptic activity. Therefore, the effects of the benzodiazepine hypnotic midazolam (10 mg/kg) and the novel imidazopyridine hypnotic zolpidem (10 mg/kg) on sleep-wake states and on the number of spike-wave discharges were evaluated in WAG/Rij rats. Rats of

[Melatonin, synthetic analogs, and the sleep/wake rhythm].

Science.gov (United States)

Escames, G; Acuña-Castroviejo, D

Melatonin, a widespread hormone in the animal kingdom, is produced by several organs and tissues besides the pineal gland. Whilst extrapineal melatonin behaves as a cytoprotective molecule, the pineal produces the hormone in a rhythmic manner. The discovery of melatonin in 1958, and the characterization of its synthesis somewhat later, let to the description of its photoperiodic regulation and its relationship with the biological rhythms such as the sleep/wake rhythm. The suprachiasmatic nuclei are the anatomical seat of the biological clock, represented by the clock genes, which code for the period and frequency of the rhythms. The photoperiod synchronizes the activity of the auprachiasmatic biological clock, which in turn induces the melatonin's rhythm. The rhythm of melatonin, peaking at 2-3 am, acts as an endogenous synchronizer that translates the environmental photoperiodic signal in chemical information for the cells. The sleep/wake cycle is a typical biological rhythm synchronized by melatonin, and the sleep/wake cycle alterations of chronobiological origin, are very sensitive to melatonin treatment. Taking advantage of the chronobiotic and antidepressive properties of melatonin, a series of synthetic analogs of this hormone, with high interest in insomnia, are now available. Melatonin is a highly effective chronobiotic in the treatment of chronobiological alterations of the sleep/wake cycle. From a pharmacokinetic point of view, the synthetic drugs derived from melatonin are interesting tools in the therapy of these alterations.

Near scale-free dynamics in neural population activity of waking/sleeping rats revealed by multiscale analysis.

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Leonid A Safonov

Full Text Available A neuron embedded in an intact brain, unlike an isolated neuron, participates in network activity at various spatial resolutions. Such multiple scale spatial dynamics is potentially reflected in multiple time scales of temporal dynamics. We identify such multiple dynamical time scales of the inter-spike interval (ISI fluctuations of neurons of waking/sleeping rats by means of multiscale analysis. The time scale of large non-Gaussianity in the ISI fluctuations, measured with the Castaing method, ranges up to several minutes, markedly escaping the low-pass filtering characteristics of neurons. A comparison between neural activity during waking and sleeping reveals that non-Gaussianity is stronger during waking than sleeping throughout the entire range of scales observed. We find a remarkable property of near scale independence of the magnitude correlations as the primary cause of persistent non-Gaussianity. Such scale-invariance of correlations is characteristic of multiplicative cascade processes and raises the possibility of the existence of a scale independent memory preserving mechanism.

Effect of Sleep/Wake Cycle on Autonomic Regulation

International Nuclear Information System (INIS)

Jabeen, S.

2015-01-01

Objective: To evaluate the association between irregular sleep/wake cycle in shift workers and autonomic regulation. Study Design: Cross-sectional, analytical study. Place and Duration of Study: Dow University Hospital, Karachi, from August to November 2013. Methodology: All health care providers working in rotating shifts making a total (n=104) were included. Instrument was an integrated questionnaire applied to assess autonomic regulation, taken from Kroz et al. on scoring criteria, ranging from 18 - 54, where higher rating signifies strong autonomic regulation, indicating a stable Autonomic Nervous System (ANS) and vice versa. Participants were interviewed and their response was recorded by the investigator. Influence of sleep misalignment was measured quantitatively to extract index of autonomic activity. Results: There was a reduced trend in autonomic strength amongst shift workers. The mean score obtained on the Autonomic Scale was 37.8 ± 5.9. Conclusion: Circadian misalignment has an injurious influence on ANS which might be valuable in controlling autonomic dysfunction that leads to fatal triggers in rotating shift workers. (author)

Connexin 43-Mediated Astroglial Metabolic Networks Contribute to the Regulation of the Sleep-Wake Cycle.

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Clasadonte, Jerome; Scemes, Eliana; Wang, Zhongya; Boison, Detlev; Haydon, Philip G

2017-09-13

Astrocytes produce and supply metabolic substrates to neurons through gap junction-mediated astroglial networks. However, the role of astroglial metabolic networks in behavior is unclear. Here, we demonstrate that perturbation of astroglial networks impairs the sleep-wake cycle. Using a conditional Cre-Lox system in mice, we show that knockout of the gap junction subunit connexin 43 in astrocytes throughout the brain causes excessive sleepiness and fragmented wakefulness during the nocturnal active phase. This astrocyte-specific genetic manipulation silenced the wake-promoting orexin neurons located in the lateral hypothalamic area (LHA) by impairing glucose and lactate trafficking through astrocytic networks. This global wakefulness instability was mimicked with viral delivery of Cre recombinase to astrocytes in the LHA and rescued by in vivo injections of lactate. Our findings propose a novel regulatory mechanism critical for maintaining normal daily cycle of wakefulness and involving astrocyte-neuron metabolic interactions. Copyright © 2017 Elsevier Inc. All rights reserved.

Waking and sleeping following water deprivation in the rat.

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Davide Martelli

Full Text Available Wake-sleep (W-S states are affected by thermoregulation. In particular, REM sleep (REMS is reduced in homeotherms under a thermal load, due to an impairment of hypothalamic regulation of body temperature. The aim of this work was to assess whether osmoregulation, which is regulated at a hypothalamic level, but, unlike thermoregulation, is maintained across the different W-S states, could influence W-S occurrence. Sprague-Dawley rats, kept at an ambient temperature of 24°C and under a 12 h∶12 h light-dark cycle, were exposed to a prolonged osmotic challenge of three days of water deprivation (WD and two days of recovery in which free access to water was restored. Two sets of parameters were determined in order to assess: i the maintenance of osmotic homeostasis (water and food consumption; changes in body weight and fluid composition; ii the effects of the osmotic challenge on behavioral states (hypothalamic temperature (Thy, motor activity, and W-S states. The first set of parameters changed in WD as expected and control levels were restored on the second day of recovery, with the exception of urinary Ca(++ that almost disappeared in WD, and increased to a high level in recovery. As far as the second set is concerned, WD was characterized by the maintenance of the daily oscillation of Thy and by a decrease in activity during the dark periods. Changes in W-S states were small and mainly confined to the dark period: i REMS slightly decreased at the end of WD and increased in recovery; ii non-REM sleep (NREMS increased in both WD and recovery, but EEG delta power, a sign of NREMS intensity, decreased in WD and increased in recovery. Our data suggest that osmoregulation interferes with the regulation of W-S states to a much lesser extent than thermoregulation.

Mecanismos do ciclo sono-vigília Sleep-wake cycle mechanisms

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Flávio Alóe

2005-05-01

Full Text Available Três sub-divisões hipotalâmicas são importantes no ciclo sono-vigília: o hipotálamo anterior (núcleos gabaérgicos e núcleos supraquiasmáticos, o hipotálamo posterior (núcleo túbero-mamilar histaminérgico e o hipotálamo lateral (sistema hipocretinas. O sistema gabaérgico inibitório do núcleo pré-óptico ventro-lateral (VLPO do hipotálamo anterior é responsável pelo início e manutenção do sono NREM. Os neurônios supraquiasmáticos (NSQs do hipotálamo anterior são responsáveis pelo ritmo circadiano do ciclo sono-vigília. Os núcleos aminérgicos, histaminérgicos, as hipocretinas e núcleos colinérgicos do prosencéfalo basal apresentam-se ativos durante a vigília, inibindo o núcleo pré-óptico ventro-lateral, promovendo a vigília. O processo de inibição-estimulação é a base do modelo da interação recíproca entre os grupos de células wake-off-sleep-on e células wake-off-sleep-on reguladores do ciclo sono-vigília. O modelo da interação recíproca também se aplica aos núcleos colinérgicos (células REM-on e aminérgicos (células REM-off do tronco cerebral no controle temporal do sono REM-NREM.Neurochemically distinct systems interact regulating sleep and wakefulness. Wakefulness is promoted by aminergic, acetylcholinergic brainstem and hypothalamic systems. Each of these arousal systems supports wakefulness and coordinated activity is required for alertness and EEG activation. Neurons in the pons and preoptic area control rapid eye movement and non-rapid eye movement sleep. Mutual inhibition between these wake- and sleep-regulating systems generate behavioral states. An up-to-date understanding of these systems should allow clinicians and researchers to better understand the effects of drugs, lesions, and neurologic disease on sleep and wakefulness.

Initiation of sleep-dependent cortical-hippocampal correlations at wakefulness-sleep transition.

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Haggerty, Daniel C; Ji, Daoyun

2014-10-01

Sleep is involved in memory consolidation. Current theories propose that sleep-dependent memory consolidation requires active communication between the hippocampus and neocortex. Indeed, it is known that neuronal activities in the hippocampus and various neocortical areas are correlated during slow-wave sleep. However, transitioning from wakefulness to slow-wave sleep is a gradual process. How the hippocampal-cortical correlation is established during the wakefulness-sleep transition is unknown. By examining local field potentials and multiunit activities in the rat hippocampus and visual cortex, we show that the wakefulness-sleep transition is characterized by sharp-wave ripple events in the hippocampus and high-voltage spike-wave events in the cortex, both of which are accompanied by highly synchronized multiunit activities in the corresponding area. Hippocampal ripple events occur earlier than the cortical high-voltage spike-wave events, and hippocampal ripple incidence is attenuated by the onset of cortical high-voltage spike waves. This attenuation leads to a temporary weak correlation in the hippocampal-cortical multiunit activities, which eventually evolves to a strong correlation as the brain enters slow-wave sleep. The results suggest that the hippocampal-cortical correlation is established through a concerted, two-step state change that first synchronizes the neuronal firing within each brain area and then couples the synchronized activities between the two regions. Copyright © 2014 the American Physiological Society.

Slow Activity in Focal Epilepsy During Sleep and Wakefulness

DEFF Research Database (Denmark)

Pellegrino, Giovanni; Tombini, Mario; Curcio, Giuseppe

2017-01-01

Introduction We aimed to test differences between healthy subjects and patients with respect to slow wave activity during wakefulness and sleep. Methods Fifteen patients affected by nonlesional focal epilepsy originating within temporal areas and fourteen matched controls underwent a 24-hour EEG....... The effect was widespread for alpha band and above, while localized over the affected hemisphere for delta (sleep cycle 1, P = .006; sleep cycle 2, P = .008; sleep cycle 3, P = .017). The analysis of interhemispheric differences showed that the only frequency band stronger over the affected regions...

Age-related changes in sleep-wake rhythm in dog.

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Takeuchi, Takashi; Harada, Etsumori

2002-10-17

To investigate a sleep-wake rhythm in aged dogs, a radio-telemetry monitoring was carried out for 24 h. Electrodes and telemetry device were surgically implanted in four aged dogs (16-18 years old) and four young dogs (3-4 years old). Electroencephalogram (EEG), electromyogram (EMG) and electrocardiogram (ECG) were recorded simultaneously as parameters to determine vigilance states and an autonomic nervous function. Wakefulness, slow wave sleep (SWS) and paradoxical sleep (PS) were identified according to the EEG and EMG pattern. We also examined whether absolute powers and the low frequency-to-high frequency ratio (LF/HF) derived from the heart rate variability power spectrum could detect shifts in autonomic balance correlated with aging. The aged dogs showed a marked reduction of PS and a fragmentation of wakefulness in the daytime and a sleep disruption in the night. The pattern of 24 h sleep and waking was dramatically altered in the aged dog. It was characterized by an increase in the total amount of time spent in SWS during the daytime followed by an increasing of time spent in wakefulness during the night. Furthermore, LF/HF ratio showed a very low amplitude of variance throughout the day in the aged dog. These results suggest that the aged dog is a useful model to investigate sleep disorders in human such as daytime drowsiness, difficulties in sleep maintenance. The abnormality in sleep-wake cycle might be reflected by the altered autonomic balance in the aged dogs.

Functional consequences of brain glycogen deficiency on the sleep-wake cycle regulation in PTG-KO mice

KAUST Repository

Burlet-Godinot, S.; Allaman, I.; Grenningloh, G.; Roach, P.J.; Depaoli-Roach, A.A.; Magistretti, Pierre J.; Petit, J.-M.

2017-01-01

in the brain in mice while glycogen levels were paradoxically maintained and not affected. In order to gain further insight on the role of PTG in this process, we studied the sleep/wake cycle parameters in PTG knockout (PTG-KO) mice under baseline conditions

Functional consequences of brain glycogen deficiency on the sleep-wake cycle regulation in PTG-KO mice

KAUST Repository

Burlet-Godinot, S.

2017-12-31

Introduction: In the CNS, glycogen is mainly localized in astrocytes where its levels are linked to neuronal activity. Astrocytic glycogen synthesis is regulated by glycogen synthase (GS) activity that is positively controlled by protein targeting to glycogen (PTG) expression levels. Although the role of glycogen in sleep/wake regulation is still poorly understood, we have previously demonstrated that, following a 6 hour gentle sleep deprivation (GSD), PTG mRNA expression and GS activity increased in the brain in mice while glycogen levels were paradoxically maintained and not affected. In order to gain further insight on the role of PTG in this process, we studied the sleep/wake cycle parameters in PTG knockout (PTG-KO) mice under baseline conditions and after a 6 hour GSD. Glycogen levels as well as mRNAs expression of genes related to energy metabolism were also determined in several brain areas. Materials and methods: Adult male C57BL/6J (WT) and PTG-KO mice were sleep-recorded under baseline conditions (24 h recordings, 12 h light/dark cycle) and following 6 hours GSD from ZT00 to ZT06. Vigilance states were visually scored (4 s temporal window). Spectral analysis of the EEG signal was performed using a discrete Fourier transformation. Glycogen measurements and gene expression analysis were assessed using a biochemical assay and quantitative RT-PCR respectively, on separate cohorts in WT vs PTG-KO mice at the end of the 6 hours GSD or in control animals (CTL) in different brain structures. Results: Quantitative analysis of the sleep/wake cycle under baseline conditions did not reveal major differences between the WT and the PTG-KO mice. However, during the dark period, the PTG-KO mice showed a significant increase in the number of wake and slow wave sleep episodes (respectively +26.5±8% and +26.1±8%; p< 0.05) together with a significant shortening in their duration (-21.6±7.2% and -14.3±2.8%; p< 0.01). No such quantitative changes were observed during

Acute Kynurenine Challenge Disrupts Sleep-Wake Architecture and Impairs Contextual Memory in Adult Rats.

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Pocivavsek, Ana; Baratta, Annalisa M; Mong, Jessica A; Viechweg, Shaun S

2017-11-01

Tryptophan metabolism via the kynurenine pathway may represent a key molecular link between sleep loss and cognitive dysfunction. Modest increases in the kynurenine pathway metabolite kynurenic acid (KYNA), which acts as an antagonist at N-methyl-d-aspartate and α7 nicotinic acetylcholine receptors in the brain, result in cognitive impairments. As glutamatergic and cholinergic neurotransmissions are critically involved in modulation of sleep, our current experiments tested the hypothesis that elevated KYNA adversely impacts sleep quality. Adult male Wistar rats were treated with vehicle (saline) and kynurenine (25, 50, 100, and 250 mg/kg), the direct bioprecursor of KYNA, intraperitoneally at zeitgeber time (ZT) 0 to rapidly increase brain KYNA. Levels of KYNA in the brainstem, cortex, and hippocampus were determined at ZT 0, ZT 2, and ZT 4, respectively. Analyses of vigilance state-related parameters categorized as wake, rapid eye movement (REM), and non-REM (NREM) as well as spectra power analysis during NREM and REM were assessed during the light phase. Separate animals were tested in the passive avoidance paradigm, testing contextual memory. When KYNA levels were elevated in the brain, total REM duration was reduced and total wake duration was increased. REM and wake architecture, assessed as number of vigilance state bouts and average duration of each bout, and theta power during REM were significantly impacted. Kynurenine challenge impaired performance in the hippocampal-dependent contextual memory task. Our results introduce kynurenine pathway metabolism and formation of KYNA as a novel molecular target contributing to sleep disruptions and cognitive impairments. © 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.

To sleep or not to sleep : new insights in sleep-wake cycles and circadian rhythmicity in the intensive care unit

NARCIS (Netherlands)

Gazendam, Joost Alexander Christiaan

2008-01-01

The main goal of this dissertation was to gain more insight into the sleep-wake behavior of intensive care unit patients and the factors that disturb it. At the beginning of this project, we firmly believed that patients experienced abnormal sleep-wake behavior. This was based on clinical

Changes in electrographic correlates of sleep-wakefulness cycle in cats irradiated with minimal lethal doses

International Nuclear Information System (INIS)

Kordzadze, R.N.; Nadarishvili, K.Sh.; Tsinitia, K.A.

1983-01-01

The paper deals with the dynamics of changes in bioelectrical activity (BEA) of the somatosensory cortex (SC) and dorsal hippocampus (DH) in the sleep-wakefulness (SW) cycle by means of a computer and automatized frequency analysis system in the course of chronic experiences with cats before and at various stages of development of radiation sickness (RS). The dose of single whole-body irradiation equaled 8 Gr (800+-20 rad). It has been shown that changes which occur in SC substantially differ in dependence on the stages of the SW cycle. More pronounced changes after irradiation are observed in low-frequency rhythms, particularly at the stage of deep slow wave sleep (DSWS) and less pronounced - in the paradoxical sleep (PS). Rhythmics shifts taking place in DH are mainly similar during wakefulness (W), superficial slow wave sleep (SSWS) and DSWS. In PS changes in rhythmics considerably differ as compared with We SSWS and DSWS. Revealed are also other specific shifts including a reliable enhancement of absolute value (AV) and specific ponderability (SP) of thera-rhythm of hippocampus during the RS acute period in animals survived the three week observation period. All this permits to conclude that BEA quantitative studies of various brain areas in the SW permit to reveal the trends in search of diagnostic and prognostic value of such investigations in case of different extreme states and to outline on the patogenetic basis correction methods for neutral disorders in case of RS

THE NEUROBIOLOGY OF SLEEP AND WAKEFULNESS

Science.gov (United States)

Schwartz, Michael D.; Kilduff, Thomas S.

2015-01-01

SYNOPSIS Since the discovery of Rapid Eye Movement (REM) sleep in the late 1950s, identification of the neural circuitry underlying wakefulness, sleep onset and the alternation between REM and non-REM (NREM) sleep has been an active area of investigation. Synchronization and desynchronization of cortical activity as detected in the electroencephalogram (EEG) is due to a corticothalamocortical loop, intrinsic cortical oscillators, monoaminergic and cholinergic afferent input to the thalamus, and the basal forebrain cholinergic input directly to the cortex. The monoaminergic and cholinergic systems are largely wake-promoting; the brainstem cholinergic nuclei are also involved in REM sleep regulation. These wake-promoting systems receive excitatory input from the hypothalamic hypocretin/orexin system. Sleep-promoting nuclei are GABAergic in nature and found in the preoptic area, brainstem and lateral hypothalamus. Although the pons is critical for the expression of REM sleep, recent research has suggested that melanin-concentrating hormone/GABAergic cells in the lateral hypothalamus "gate" REM sleep. The temporal distribution of sleep and wakefulness is due to interaction between the circadian system and the sleep homeostatic system. Although the hypothalamic suprachiasmatic nuclei contain the circadian pacemaker, the neural circuitry underlying the sleep homeostat is less clear. Prolonged wakefulness results in the accumulation of extracellular adenosine, possibly from glial sources, which is an important feedback molecule for the sleep homeostatic system. Cortical neuronal nitric oxide (nNOS) neurons may also play a role in propagating slow waves through the cortex in NREM sleep. Several neuropeptides and other neurochemicals likely play important roles in sleep/wake control. Although the control of sleep and wakefulness seemingly involves multiple redundant systems, each of these systems provides a vulnerability that can result in sleep/wake dysfunction that may

Wheel running improves REM sleep and attenuates stress-induced flattening of diurnal rhythms in F344 rats.

Science.gov (United States)

Thompson, Robert S; Roller, Rachel; Greenwood, Benjamin N; Fleshner, Monika

2016-05-01

Regular physical activity produces resistance to the negative health consequences of stressor exposure. One way that exercise may confer stress resistance is by reducing the impact of stress on diurnal rhythms and sleep; disruptions of which contribute to stress-related disease including mood disorders. Given the link between diurnal rhythm disruptions and stress-related disorders and that exercise both promotes stress resistance and is a powerful non-photic biological entrainment cue, we tested if wheel running could reduce stress-induced disruptions of sleep/wake behavior and diurnal rhythms. Adult, male F344 rats with or without access to running wheels were instrumented for biotelemetric recording of diurnal rhythms of locomotor activity, heart rate, core body temperature (CBT), and sleep (i.e. REM, NREM, and WAKE) in the presence of a 12 h light/dark cycle. Following 6 weeks of sedentary or exercise conditions, rats were exposed to an acute stressor known to disrupt diurnal rhythms and produce behaviors associated with mood disorders. Prior to stressor exposure, exercise rats had higher CBT, more locomotor activity during the dark cycle, and greater %REM during the light cycle relative to sedentary rats. NREM and REM sleep were consolidated immediately following peak running to a greater extent in exercise, compared to sedentary rats. In response to stressor exposure, exercise rats expressed higher stress-induced hyperthermia than sedentary rats. Stressor exposure disrupted diurnal rhythms in sedentary rats; and wheel running reduced these effects. Improvements in sleep and reduced diurnal rhythm disruptions following stress could contribute to the health promoting and stress protective effects of exercise.

No Acute Effects of Cannabidiol on the Sleep-Wake Cycle of Healthy Subjects: A Randomized, Double-Blind, Placebo-Controlled, Crossover Study.

Science.gov (United States)

Linares, Ila M P; Guimaraes, Francisco S; Eckeli, Alan; Crippa, Ana C S; Zuardi, Antonio W; Souza, Jose D S; Hallak, Jaime E; Crippa, José A S

2018-01-01

Cannabidiol (CBD) is a component of Cannabis sativa that has a broad spectrum of potential therapeutic effects in neuropsychiatric and other disorders. However, few studies have investigated the possible interference of CBD on the sleep-wake cycle. The aim of the present study was to evaluate the effect of a clinically anxiolytic dose of CBD on the sleep-wake cycle of healthy subjects in a crossover, double-blind design. Twenty-seven healthy volunteers that fulfilled the eligibility criteria were selected and allocated to receive either CBD (300 mg) or placebo in the first night in a double-blind randomized design (one volunteer withdrew from the study). In the second night, the same procedure was performed using the substance that had not been administered in the previous occasion. CBD or placebo were administered 30 min before the start of polysomnography recordings that lasted 8 h. Cognitive and subjective measures were performed immediately after polysomnography to assess possible residual effects of CBD. The drug did not induce any significant effect ( p > 0.05). Different from anxiolytic and antidepressant drugs such as benzodiazepines and selective serotonin reuptake inhibitors, acute administration of an anxiolytic dose of CBD does not seem to interfere with the sleep cycle of healthy volunteers. The present findings support the proposal that CBD do not alter normal sleep architecture. Future studies should address the effects of CBD on the sleep-wake cycle of patient populations as well as in clinical trials with larger samples and chronic use of different doses of CBD. Such studies are desirable and opportune.

No Acute Effects of Cannabidiol on the Sleep-Wake Cycle of Healthy Subjects: A Randomized, Double-Blind, Placebo-Controlled, Crossover Study

Directory of Open Access Journals (Sweden)

Ila M. P. Linares

2018-04-01

Full Text Available Cannabidiol (CBD is a component of Cannabis sativa that has a broad spectrum of potential therapeutic effects in neuropsychiatric and other disorders. However, few studies have investigated the possible interference of CBD on the sleep-wake cycle. The aim of the present study was to evaluate the effect of a clinically anxiolytic dose of CBD on the sleep-wake cycle of healthy subjects in a crossover, double-blind design. Twenty-seven healthy volunteers that fulfilled the eligibility criteria were selected and allocated to receive either CBD (300 mg or placebo in the first night in a double-blind randomized design (one volunteer withdrew from the study. In the second night, the same procedure was performed using the substance that had not been administered in the previous occasion. CBD or placebo were administered 30 min before the start of polysomnography recordings that lasted 8 h. Cognitive and subjective measures were performed immediately after polysomnography to assess possible residual effects of CBD. The drug did not induce any significant effect (p > 0.05. Different from anxiolytic and antidepressant drugs such as benzodiazepines and selective serotonin reuptake inhibitors, acute administration of an anxiolytic dose of CBD does not seem to interfere with the sleep cycle of healthy volunteers. The present findings support the proposal that CBD do not alter normal sleep architecture. Future studies should address the effects of CBD on the sleep-wake cycle of patient populations as well as in clinical trials with larger samples and chronic use of different doses of CBD. Such studies are desirable and opportune.

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

Science.gov (United States)

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.

Clinical Practice Guideline for the Treatment of Intrinsic Circadian Rhythm Sleep-Wake Disorders: Advanced Sleep-Wake Phase Disorder (ASWPD), Delayed Sleep-Wake Phase Disorder (DSWPD), Non-24-Hour Sleep-Wake Rhythm Disorder (N24SWD), and Irregular Sleep-Wake Rhythm Disorder (ISWRD). An Update for 2015

Science.gov (United States)

Auger, R. Robert; Burgess, Helen J.; Emens, Jonathan S.; Deriy, Ludmila V.; Thomas, Sherene M.; Sharkey, Katherine M.

2015-01-01

A systematic literature review and meta-analyses (where appropriate) were performed and the GRADE approach was used to update the previous American Academy of Sleep Medicine Practice Parameters on the treatment of intrinsic circadian rhythm sleep-wake disorders. Available data allowed for positive endorsement (at a second-tier degree of confidence) of strategically timed melatonin (for the treatment of DSWPD, blind adults with N24SWD, and children/ adolescents with ISWRD and comorbid neurological disorders), and light therapy with or without accompanying behavioral interventions (adults with ASWPD, children/adolescents with DSWPD, and elderly with dementia). Recommendations against the use of melatonin and discrete sleep-promoting medications are provided for demented elderly patients, at a second- and first-tier degree of confidence, respectively. No recommendations were provided for remaining treatments/ populations, due to either insufficient or absent data. Areas where further research is needed are discussed. Citation: Auger RR, Burgess HJ, Emens JS, Deriy LV, Thomas SM, Sharkey KM. Clinical practice guideline for the treatment of intrinsic circadian rhythm sleep-wake disorders: advanced sleep-wake phase disorder (ASWPD), delayed sleep-wake phase disorder (DSWPD), non-24-hour sleep-wake rhythm disorder (N24SWD), and irregular sleep-wake rhythm disorder (ISWRD). An update for 2015. J Clin Sleep Med 2015;11(10):1199–1236. PMID:26414986

Evaluation of the effect of chronic exposure to 137Cesium on sleep-wake cycle in rats

International Nuclear Information System (INIS)

Lestaevel, Philippe; Dhieux, Bernadette; Tourlonias, Elie; Houpert, Pascale; Paquet, Francois; Voisin, Philippe; Aigueperse, Jocelyne; Gourmelon, Patrick

2006-01-01

Since the Chernobyl accident, the most significant problem for the population living in the contaminated areas is chronic exposure by ingestion of radionuclides, notably 137 Cs, a radioactive isotope of cesium. It can be found in the whole body, including the central nervous system. The present study aimed to assess the effect of 137 Cs on the central nervous system and notably on open-field activity and the electroencephalographic pattern. Rats were exposed up to 90 days to drinking water contaminated with 137 Cs at a dosage of 400 Bq kg -1 , which is similar to that ingested by the population living in contaminated territories. At this level of exposure, no significant effect was observed on open-field activity. On the other hand, at 30 days exposure, 137 Cs decreased the number of episodes of wakefulness and slow wave sleep and increased the mean duration of these stages. At 90 days exposure, the power of 0.5-4 Hz band of 137 Cs-exposed rats was increased in comparison with controls. These electrophysiological changes may be due to a regional 137 Cs accumulation in the brain stem. In conclusion, the neurocognitive effects of 137 Cs need further evaluation and central disorders of population living in contaminated territories must be considered

Music exposure and maturation of late preterm sleep-wake cycles: a randomised crossover trial.

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Stokes, Adia; Agthe, Alexander G; El Metwally, Dina

2018-04-01

To determine the effect of music on sleep-wake cycle (SWC) patterns in late preterm neonates. In a masked crossover study, infants between 32 and 36 6/7 weeks gestation were randomised to music exposure either during the first six or last six hours of a 12-hour observation period. SWC characteristics were determined by continuous amplitude-integrated electroencephalography (aEEG) read by two coders masked to exposure sequence. Analysis was performed in paired comparisons. ANOVA was used to assess the effects of music exposure, period and crossover on SWC outcomes: (i) Burdjalov Scores (BS) during active sleep (AS) (ii) per cent and duration of quiet sleep (QS). Thirty infants were studied. A total of 222 QS cycles (median seven per patient; range five to 12) were analysed. Music exposure was associated with higher BS (F = 10.60, p = 0.0019) in AS and decreased interruptions during QS. The advanced postconceptual age (PCA) SWC pattern during AS was equivalent to a one-week mean. Number, duration and ratio of QS cycles did not change with music exposure. Music exposure elicits an increasing PCA pattern in AS and fewer interruptions in QS. Music may benefit sleep in late preterm infants. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

Sleep-wake sensitive mechanisms of adenosine release in the basal forebrain of rodents: an in vitro study.

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Robert Edward Sims

Full Text Available Adenosine acting in the basal forebrain is a key mediator of sleep homeostasis. Extracellular adenosine concentrations increase during wakefulness, especially during prolonged wakefulness and lead to increased sleep pressure and subsequent rebound sleep. The release of endogenous adenosine during the sleep-wake cycle has mainly been studied in vivo with microdialysis techniques. The biochemical changes that accompany sleep-wake status may be preserved in vitro. We have therefore used adenosine-sensitive biosensors in slices of the basal forebrain (BFB to study both depolarization-evoked adenosine release and the steady state adenosine tone in rats, mice and hamsters. Adenosine release was evoked by high K(+, AMPA, NMDA and mGlu receptor agonists, but not by other transmitters associated with wakefulness such as orexin, histamine or neurotensin. Evoked and basal adenosine release in the BFB in vitro exhibited three key features: the magnitude of each varied systematically with the diurnal time at which the animal was sacrificed; sleep deprivation prior to sacrifice greatly increased both evoked adenosine release and the basal tone; and the enhancement of evoked adenosine release and basal tone resulting from sleep deprivation was reversed by the inducible nitric oxide synthase (iNOS inhibitor, 1400 W. These data indicate that characteristics of adenosine release recorded in the BFB in vitro reflect those that have been linked in vivo to the homeostatic control of sleep. Our results provide methodologically independent support for a key role for induction of iNOS as a trigger for enhanced adenosine release following sleep deprivation and suggest that this induction may constitute a biochemical memory of this state.

Reviews/Essays: School Start Times and the Sleep-Wake Cycle of Adolescents--A Review and Critical Evaluation of Available Evidence

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Kirby, Matthew; Maggi, Stefania; D'Angiulli, Amedeo

2011-01-01

The authors have integrated the major findings on the sleep-wake cycle and its performance correlates in adolescents. Basic research shows that lack of synchronicity between early school start times and the circadian rhythm of adolescents (and the sleep debt accumulated as a result) involves several cognitive correlates that may harm the academic…

Three-dimensional structural representation of the sleep-wake adaptability.

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Putilov, Arcady A

2016-01-01

Various characteristics of the sleep-wake cycle can determine the success or failure of individual adjustment to certain temporal conditions of the today's society. However, it remains to be explored how many such characteristics can be self-assessed and how they are inter-related one to another. The aim of the present report was to apply a three-dimensional structural representation of the sleep-wake adaptability in the form of "rugby cake" (scalene or triaxial ellipsoid) to explain the results of analysis of the pattern of correlations of the responses to the initial 320-item list of a new inventory with scores on the six scales designed for multidimensional self-assessment of the sleep-wake adaptability (Morning and Evening Lateness, Anytime and Nighttime Sleepability, and Anytime and Daytime Wakeability). The results obtained for sample consisting of 149 respondents were confirmed by the results of similar analysis of earlier collected responses of 139 respondents to the same list of 320 items and responses of 1213 respondents to the 72 items of one of the earlier established questionnaire tools. Empirical evidence was provided in support of the model-driven prediction of the possibility to identify items linked to as many as 36 narrow (6 core and 30 mixed) adaptabilities of the sleep-wake cycle. The results enabled the selection of 168 items for self-assessment of all these adaptabilities predicted by the rugby cake model.

Differences in activity of cytochrome C oxidase in brain between sleep and wakefulness.

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Nikonova, Elena V; Vijayasarathy, Camasamudram; Zhang, Lin; Cater, Jacqueline R; Galante, Raymond J; Ward, Stephen E; Avadhani, Narayan G; Pack, Allan I

2005-01-01

Increased mRNA level of subunit 1 cytochrome c oxidase (COXI) during wakefulness and after short-term sleep deprivation has been described in brain. We hypothesized that this might contribute to increased activity of cytochrome oxidase (COX) enzyme during wakefulness, as part of the mechanisms to provide sufficient amounts of adenosine triphosphate to meet increased neuronal energy demands. COX activity was measured in isolated mitochondria from different brain regions in groups of rats with 3 hours of spontaneous sleep, 3 hours of spontaneous wake, and 3 hours of sleep deprivation. The group with 3 hours of spontaneous wake was added to delineate the circadian component of changes in the enzyme activity. Northern blot analysis was performed to examine the mRNA levels of 2 subunits of the enzyme COXI and COXIV, encoded by mitochondrial and nuclear DNA, respectively. Laboratory of Biochemistry, Department of Animal Biology, and Center for Sleep and Respiratory Neurobiology, University of Pennsylvania. 2-month-old male Fischer rats (N = 21) implanted for polygraphic recording. For COX activity, there was a main effect by analysis of variance of experimental group (P sleep-deprived groups as compared to the sleep group. A main effect of brain region was also significant (P sleep. There is an increase in COX activity after both 3 hours of spontaneous wake and 3 hours of sleep deprivation as compared with 3 hours of spontaneous sleep in diverse brain regions, which could be, in part, explained by the increased levels of bigenomic transcripts of the enzyme. This likely contributes to increased adenosine triphosphate production during wakefulness. ADP, adenosine diphosphate; ATP, adenosine triphosphate; COXI, cytochrome c oxidase subunit 1 mRNA; COX, cytochrome c oxidase (protein); CREB, cyclic AMP response element binding protein; DNA, deoxyribonucleic acid; EDTA, ethylenediaminetetraacetic acid; EEG, electroencephalography; EMG, electromyography; GABP, GA binding

Sleep-Wake Patterns and Sleep Disturbance among Hong Kong Chinese Adolescents

OpenAIRE

Chung, Ka-Fai; Cheung, Miao-Miao

2008-01-01

STUDY OBJECTIVES: 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. DESIGN AND SETTING: A school-based cross-sectional survey. PARTICIPANTS: Sample included 1629 adolescents aged 12 to 19 years. MEASUREMENTS AND RESULTS: Self-report questionnaires, including sleep-wake habit questionnaire,...

The relationship of luteinizing hormone secretion to sleep in women during the early follicular phase: effects of sleep reversal and a prolonged three-hour sleep-wake schedule.

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Kapen, S; Boyar, R; Hellman, L; Weitzman, E D

1976-06-01

The relationship of luteinizing hormone (LH) secretion to sleep in adult women was investigated in two ways: an acute 180 degrees sleep-wake cycle reversal in a group of six women and a schedule in which a young woman engaged in a three hour sleep-wake cycle (two hours awake, one hour allowed for sleep continuously for ten days--the study was carried out on the eighth day). Each subject in the reversal study had a baseline period during which plasma samples were collected every twenty minutes for twenty-four hours and nocturnal sleep was monitored electrophysiologically during the early follicular phase of the menstrual cycle. During a succeeding cycle, the study was repeated after sleep-wake reversal. LH secretory patterns were analyzed by comparing the 24-hour mean plasma LH concentration with the hourly averages in percentage terms, using Stage 2 sleep onset as the zero point. LH secretion was depressed to approximately the same degree in both the baseline and reversal studies. The average hourly percentage difference from the 24-hour mean for the four-hour period following sleep onset was -13.4% and -13.1% for the baseline and reversal, respectively. These percentage deviations represented practically the entire negative deviation for the 24-hour period in both studies. The difference between the first four-hour period after sleep onset and the second was significant. The subject on a three-hour cycle had a baseline in which a large decrease in LH secretion occurred after sleep onset (-52.2% during the third hour). Her LH secretory pattern during the three-hour sleep-wake schedule was characterized by a fall during sleep periods, particularly when slow wave sleep (SWS) predominated. However, no correlation was found between specific sleep stages and LH secretion in the six women of the reversal study. These results confirm a relationship of LH secretion to sleep in adult women, one which is different from that described during puberty.

The role of serotonin and norepinephrine in sleep-waking activity.

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Morgane, P J; Stern, W C

1975-11-01

A critical review of the evidences relating the biogenic amines serotonin and norepinephrine to the states of slow-wave and rapid eye movement (REM) sleep is presented. Various alternative explanations for specific chemical regulation of the individual sleep states, including the phasic events of REM sleep, are evaluated within the overall framework of the monoamine theory of sleep. Several critical neuropsychopharmacological studies relating to metabolsim of the amines in relation to sleep-waking behavior are presented. Models of the chemical neuronal circuitry involved in sleep-waking activity are derived and interactions between several brainstem nuclei, particularly the raphé complex and locus coeruleus, are discussed. Activity in these aminergic systems in relation to oscillations in the sleep-waking cycles is evaluated. In particular, the assessment of single cell activity in specific chemical systems in relations to chemical models of sleep is reviewed. Overall, it appears that the biogenic amines, especially serotonin and norepinephrine, play key roles in the generation and maintenance of the sleep states. These neurotransmitters participate in some manner in the "triggering" processes necessary for actuating each sleep phase and in regulating the transitions from sleep to waking activity. The biogenic amines are, however, probably not "sleep factors" or direct inducers of the sleep states. Rather, they appear to be components of a multiplicity of interacting chemical circuitry in the brain whose activity maintains various chemical balances in different brain regions. Shifts in these balances appear to be involved in the triggering and maintenance of the various states comprising the vigilance continuum.

Non-24-hour sleep-wake disorder revisited – A case study

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Corrado eGarbazza

2016-02-01

Full Text Available The human sleep-wake cycle is governed by two major factors: a homeostatic hourglass process (process S, which rises linearly during the day, and a circadian process C, which determines the timing of sleep in an approximately 24h rhythm in accordance to the external light-dark (LD cycle. While both individual processes are fairly well characterized, the exact nature of their interaction remains unclear. The circadian rhythm is generated by the subthalamic nucleus (SCN, master clock of the anterior hypothalamus, through cell-autonomous feedback loops of DNA transcription and translation. While the phase length (tau of the cycle is relatively stable and genetically determined, the phase of the clock is reset by external stimuli (zeitgebers, the most important being the LD-cycle. Misalignments of the internal rhythm with the LD-cycle can lead to various somatic complaints and ultimately to the development of circadian rhythm sleep disorders (CRSD. Non-24-h sleep-wake disorders (N24HSWD is a CRSD affecting up to 50% of totally blind patients and characterized by the inability to maintain a stable entrainment of the typically long circadian rhythm (tau >24.5h to the LD- cycle. The disease is rare (<1:1 Mio in sighted individuals and the pathophysiology less well understood.Here we present the case of a 40 year old sighted male, who developed a misalignment of the internal clock with the external light-dark cycle following the treatment for Hodgkin’s lymphoma (ABVD regimen, 4 cycles and AVD regimen, 4 cycles. A thorough clinical assessment including actigraphy, melatonin profiles, polysomnography and wake-EEG lead to the diagnosis of a non-24-h sleep-wake disorders (N24HSWD with a free-running rhythm of tau=25.5h. A therapeutic intervention with bright-light therapy (BLT, 30 min 10.000lux in the morning and melatonin administration (0.5-0.75 mg in the evening failed to entrain the free-running rhythm, although a longer treatment duration and more

Sleep/wake firing patterns of human genioglossus motor units.

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Bailey, E Fiona; Fridel, Keith W; Rice, Amber D

2007-12-01

Although studies of the principal tongue protrudor muscle genioglossus (GG) suggest that whole muscle GG electromyographic (EMG) activities are preserved in nonrapid eye movement (NREM) sleep, it is unclear what influence sleep exerts on individual GG motor unit (MU) activities. We characterized the firing patterns of human GG MUs in wakefulness and NREM sleep with the aim of determining 1) whether the range of MU discharge patterns evident in wakefulness is preserved in sleep and 2) what effect the removal of the "wakefulness" input has on the magnitude of the respiratory modulation of MU activities. Microelectrodes inserted into the extrinsic tongue protrudor muscle, the genioglossus, were used to follow the discharge of single MUs. We categorized MU activities on the basis of the temporal relationship between the spike train and the respiration cycle and quantified the magnitude of the respiratory modulation of each MU using the eta (eta(2)) index, in wakefulness and sleep. The majority of MUs exhibited subtle increases or decreases in respiratory modulation but were otherwise unaffected by NREM sleep. In contrast, 30% of MUs exhibited marked sleep-associated changes in discharge frequency and respiratory modulation. We suggest that GG MUs should not be considered exclusively tonic or phasic; rather, the discharge pattern appears to be a flexible feature of GG activities in healthy young adults. Whether such flexibility is important in the response to changes in the chemical and/or mechanical environment and whether it is preserved as a function of aging or in individuals with obstructive sleep apnea are critical questions for future research.

Cordycepin Increases Nonrapid Eye Movement Sleep via Adenosine Receptors in Rats.

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Hu, Zhenzhen; Lee, Chung-Il; Shah, Vikash Kumar; Oh, Eun-Hye; Han, Jin-Yi; Bae, Jae-Ryong; Lee, Kinam; Chong, Myong-Soo; Hong, Jin Tae; Oh, Ki-Wan

2013-01-01

Cordycepin (3'-deoxyadenosine) is a naturally occurring adenosine analogue and one of the bioactive constituents isolated from Cordyceps militaris/Cordyceps sinensis, species of the fungal genus Cordyceps. It has traditionally been a prized Chinese folk medicine for the human well-being. Because of similarity of chemical structure of adenosine, cordycepin has been focused on the diverse effects of the central nervous systems (CNSs), like sleep regulation. Therefore, this study was undertaken to know whether cordycepin increases the natural sleep in rats, and its effect is mediated by adenosine receptors (ARs). Sleep was recorded using electroencephalogram (EEG) for 4 hours after oral administration of cordycepin in rats. Sleep architecture and EEG power spectra were analyzed. Cordycepin reduced sleep-wake cycles and increased nonrapid eye movement (NREM) sleep. Interestingly, cordycepin increased θ (theta) waves power density during NREM sleep. In addition, the protein levels of AR subtypes (A1, A2A, and A2B) were increased after the administration of cordycepin, especially in the rat hypothalamus which plays an important role in sleep regulation. Therefore, we suggest that cordycepin increases theta waves power density during NREM sleep via nonspecific AR in rats. In addition, this experiment can provide basic evidence that cordycepin may be helpful for sleep-disturbed subjects.

Cordycepin Increases Nonrapid Eye Movement Sleep via Adenosine Receptors in Rats

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Zhenzhen Hu

2013-01-01

Full Text Available Cordycepin (3′-deoxyadenosine is a naturally occurring adenosine analogue and one of the bioactive constituents isolated from Cordyceps militaris/Cordyceps sinensis, species of the fungal genus Cordyceps. It has traditionally been a prized Chinese folk medicine for the human well-being. Because of similarity of chemical structure of adenosine, cordycepin has been focused on the diverse effects of the central nervous systems (CNSs, like sleep regulation. Therefore, this study was undertaken to know whether cordycepin increases the natural sleep in rats, and its effect is mediated by adenosine receptors (ARs. Sleep was recorded using electroencephalogram (EEG for 4 hours after oral administration of cordycepin in rats. Sleep architecture and EEG power spectra were analyzed. Cordycepin reduced sleep-wake cycles and increased nonrapid eye movement (NREM sleep. Interestingly, cordycepin increased θ (theta waves power density during NREM sleep. In addition, the protein levels of AR subtypes (A1, A2A, and A2B were increased after the administration of cordycepin, especially in the rat hypothalamus which plays an important role in sleep regulation. Therefore, we suggest that cordycepin increases theta waves power density during NREM sleep via nonspecific AR in rats. In addition, this experiment can provide basic evidence that cordycepin may be helpful for sleep-disturbed subjects.

Intermediate stage of sleep and acute cerveau isolé preparation in the rat.

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User, P; Gioanni, H; Gottesmann, C

1980-01-01

The acute cerveau isole rat shows spindle bursts of large amplitude alternating with low voltage activity in the frontal cortex and continuous theta rhythm in the dorsal hippocampus. These patterns closely resemble an "intermediate" stage of sleep-waking cycle, when the forebrain structures seem to be functionally disconnected from the brainstem.

Discharge properties of upper airway motor units during wakefulness and sleep.

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Trinder, John; Jordan, Amy S; Nicholas, Christian L

2014-01-01

Upper airway muscle motoneurons, as assessed at the level of the motor unit, have a range of different discharge patterns, varying as to whether their activity is modulated in phase with the respiratory cycle, are predominantly inspiratory or expiratory, or are phasic as opposed to tonic. Two fundamental questions raised by this observation are: how are synaptic inputs from premotor neurons distributed over motoneurons to achieve these different discharge patterns; and how do different discharge patterns contribute to muscle function? We and others have studied the behavior of genioglossus (GG) and tensor palatini (TP) single motor units at transitions from wakefulness to sleep (sleep onset), from sleep to wakefulness (arousal from sleep), and during hypercapnia. Results indicate that decreases or increases in GG and TP muscle activity occur as a consequence of derecruitment or recruitment, respectively, of phasic and tonic inspiratory-modulated motoneurons, with only minor changes in rate coding. Further, sleep-wake state and chemical inputs to this "inspiratory system" appear to be mediated through the respiratory pattern generator. In contrast, phasic and tonic expiratory units and units with a purely tonic pattern, the "tonic system," are largely unaffected by sleep-wake state, and are only weakly influenced by chemical stimuli and the respiratory cycle. We speculate that the "inspiratory system" produces gross changes in upper airway muscle activity in response to changes in respiratory drive, while the "tonic system" fine tunes airway configuration with activity in this system being determined by local mechanical conditions. © 2014 Elsevier B.V. All rights reserved.

Circadian Rhythm Sleep-Wake Disorders in Older Adults.

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Kim, Jee Hyun; Duffy, Jeanne F

2018-03-01

The timing, duration, and consolidation of sleep result from the interaction of the circadian timing system with a sleep-wake homeostatic process. When aligned and functioning optimally, this allows wakefulness throughout the day and a long consolidated sleep episode at night. Mismatch between the desired timing of sleep and the ability to fall and remain asleep is a hallmark of the circadian rhythm sleep-wake disorders. This article discusses changes in circadian regulation of sleep with aging; how age influences the prevalence, diagnosis, and treatment of circadian rhythm sleep-wake disorders; and how neurologic diseases in older patients affect circadian rhythms and sleep. Copyright © 2017 Elsevier Inc. All rights reserved.

Sleep-wake disturbances after traumatic brain injury.

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Ouellet, Marie-Christine; Beaulieu-Bonneau, Simon; Morin, Charles M

2015-07-01

Sleep-wake disturbances are extremely common after a traumatic brain injury (TBI). The most common disturbances are insomnia (difficulties falling or staying asleep), increased sleep need, and excessive daytime sleepiness that can be due to the TBI or other sleep disorders associated with TBI, such as sleep-related breathing disorder or post-traumatic hypersomnia. Sleep-wake disturbances can have a major effect on functional outcomes and on the recovery process after TBI. These negative effects can exacerbate other common sequelae of TBI-such as fatigue, pain, cognitive impairments, and psychological disorders (eg, depression and anxiety). Sleep-wake disturbances associated with TBI warrant treatment. Although evidence specific to patients with TBI is still scarce, cognitive-behavioural therapy and medication could prove helpful to alleviate sleep-wake disturbances in patients with a TBI. Copyright © 2015 Elsevier Ltd. All rights reserved.

Chronic sleep curtailment, even without extended (>16-h) wakefulness, degrades human vigilance performance.

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McHill, Andrew W; Hull, Joseph T; Wang, Wei; Czeisler, Charles A; Klerman, Elizabeth B

2018-05-21

Millions of individuals routinely remain awake for more than 18 h daily, which causes performance decrements. It is unknown if these functional impairments are the result of that extended wakefulness or from the associated shortened sleep durations. We therefore examined changes in objective reaction time performance and subjective alertness in a 32-d inpatient protocol in which participants were scheduled to wakefulness durations below 16 h while on a 20-h "day," with randomization into standard sleep:wake ratio (1:2) or chronic sleep restriction (CSR) ratio (1:3.3) conditions. This protocol allowed determination of the contribution of sleep deficiency independent of extended wakefulness, since individual episodes of wakefulness in the CSR condition were only 15.33 h in duration (less than the usual 16 h of wakefulness in a 24-h day) and sleep episodes were 4.67 h in duration each cycle. We found that chronic short sleep duration, even without extended wakefulness, doubled neurobehavioral reaction time performance and increased lapses of attention fivefold, yet did not uniformly decrease self-reported alertness. Further, these impairments in neurobehavioral performance were worsened during the circadian night and were not recovered during the circadian day, indicating that the deleterious effect from the homeostatic buildup of CSR is expressed even during the circadian promotion of daytime arousal. These findings reveal a fundamental aspect of human biology: Chronic insufficient sleep duration equivalent to 5.6 h of sleep opportunity per 24 h impairs neurobehavioral performance and self-assessment of alertness, even without extended wakefulness.

Non-24-Hour Sleep-Wake Disorder Revisited - A Case Study.

Science.gov (United States)

Garbazza, Corrado; Bromundt, Vivien; Eckert, Anne; Brunner, Daniel P; Meier, Fides; Hackethal, Sandra; Cajochen, Christian

2016-01-01

The human sleep-wake cycle is governed by two major factors: a homeostatic hourglass process (process S), which rises linearly during the day, and a circadian process C, which determines the timing of sleep in a ~24-h rhythm in accordance to the external light-dark (LD) cycle. While both individual processes are fairly well characterized, the exact nature of their interaction remains unclear. The circadian rhythm is generated by the suprachiasmatic nucleus ("master clock") of the anterior hypothalamus, through cell-autonomous feedback loops of DNA transcription and translation. While the phase length (tau) of the cycle is relatively stable and genetically determined, the phase of the clock is reset by external stimuli ("zeitgebers"), the most important being the LD cycle. Misalignments of the internal rhythm with the LD cycle can lead to various somatic complaints and to the development of circadian rhythm sleep disorders (CRSD). Non-24-hour sleep-wake disorders (N24HSWD) is a CRSD affecting up to 50% of totally blind patients and characterized by the inability to maintain a stable entrainment of the typically long circadian rhythm (tau > 24.5 h) to the LD cycle. The disease is rare in sighted individuals and the pathophysiology less well understood. Here, we present the case of a 40-year-old sighted male, who developed a misalignment of the internal clock with the external LD cycle following the treatment for Hodgkin's lymphoma (ABVD regimen, four cycles and AVD regimen, four cycles). A thorough clinical assessment, including actigraphy, melatonin profiles and polysomnography led to the diagnosis of non-24-hour sleep-wake disorders (N24HSWD) with a free-running rhythm of tau = 25.27 h. A therapeutic intervention with bright light therapy (30 min, 10,000 lux) in the morning and melatonin administration (0.5-0.75 mg) in the evening failed to entrain the free-running rhythm, although a longer treatment duration and more intense therapy might have

The role of nucleus accumbens core/shell in sleep-wake regulation and their involvement in modafinil-induced arousal.

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Mei-Hong Qiu

Full Text Available BACKGROUND: We have previously shown that modafinil promotes wakefulness via dopamine receptor D(1 and D(2 receptors; however, the locus where dopamine acts has not been identified. We proposed that the nucleus accumbens (NAc that receives the ventral tegmental area dopamine inputs play an important role not only in reward and addiction but also in sleep-wake cycle and in mediating modafinil-induced arousal. METHODOLOGY/PRINCIPAL FINDINGS: In the present study, we further explored the role of NAc in sleep-wake cycle and sleep homeostasis by ablating the NAc core and shell, respectively, and examined arousal response following modafinil administration. We found that discrete NAc core and shell lesions produced 26.5% and 17.4% increase in total wakefulness per day, respectively, with sleep fragmentation and a reduced sleep rebound after a 6-hr sleep deprivation compared to control. Finally, NAc core but not shell lesions eliminated arousal effects of modafinil. CONCLUSIONS/SIGNIFICANCE: These results indicate that the NAc regulates sleep-wake behavior and mediates arousal effects of the midbrain dopamine system and stimulant modafinil.

Sleep-Wake Patterns of Adolescents with Borderline Personality Disorder and Bipolar Disorder.

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Huỳnh, Christophe; Guilé, Jean-Marc; Breton, Jean-Jacques; Godbout, Roger

2016-04-01

Sleep-wake patterns are rarely examined in adolescents with borderline personality disorder (BPD) or bipolar disorder (BD). Within a developmental perspective, this study explores the sleep-wake cycle of adolescents aged 12-17 years with BPD or BD and healthy controls (HC) during periods with and without entrainment by school/work schedules. Eighteen euthymic BPD, six euthymic BD, and 20 HC adolescents wore wrist actigraphy during nine consecutive days to assess sleep-wake patterns. During school/work days, BPD adolescents spent more time awake when they were in bed compared to HC and BD adolescents (p = 0.039). On schedule-free days, BPD and BD youths spent more time in bed compared to HC adolescents (p = 0.015). BPD adolescents woke up over 1 h later compared to HC (p = 0.003). Total sleep time was more variable between nights in BPD adolescents compared to the HC group (p = 0.031). Future research should explore if sleep-wake pattern disruptions are a cause or a consequence of BPD symptomatology in adolescents. Addressing sleep-wake pattern during clinical assessment and treatment of BPD adolescents may potentially reduce their symptoms; this therapeutic effect still needs to be evaluated.

[Effects of afloqualone, a centrally acting muscle relaxant, on the sleep-wakefulness cycle in cats with chronically implanted electrodes (author's transl)].

Science.gov (United States)

Kojima, M; Kudo, Y; Ishida, R

1981-11-01

The present study was carried out to elucidate whether or whether not afloqualone has a hypnotic action because of its similarity in chemical structure to methaqualone. In the sleep-wakefulness cycles during the 8-hour observation period (9:00-17:00), afloqualone increased the percentages of resting (REST) and slow wave light sleep (SWLS) stages at a dose of 25 mg/kg (p.o.), producing a moderate muscle relaxation. Even at a dose of 50 mg/kg (p.o.) where a marked muscle relaxation was produced, afloqualone had no influence on the percentage of slow wave deep sleep (SWDS) stage, though it increased the percentages of SWLS and decreased the percentages of awake (AWK), REST and fast wave sleep (FWS) stages. On the other hand, tolperisone . HCl, chlormezanone, methaqualone and pentobarbital . Na, used as the reference drugs, all increased the percentage of SWDS stage, but either decreased or had no effect on the percentages of the other four stages at pharmacologically effective doses. From these results it was concluded that afloqualone seems to be devoid of a hypnotic action and has different effects on the sleep-wakefulness cycle than those of both the hypnotics and the other muscle relaxants used.

Moderating effect of APOE ε4 on the relationship between sleep-wake cycle and brain β-amyloid.

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Hwang, Jeong Yeon; Byun, Min Soo; Choe, Young Min; Lee, Jun Ho; Yi, Dahyun; Choi, Jae-Won; Hwang, Su Hwan; Lee, Yu Jin; Lee, Dong Young

2018-03-27

To clarify the relationships between sleep-wake cycle and cerebral β-amyloid (Aβ) deposition in cognitively normal (CN) older adults, focusing primarily on the moderating effects of the APOE ε4 allele. The present study included 133 CN older adults who participated in the Korean Brain Aging Study for Early Diagnosis & Prediction of Alzheimer's Disease cohort. All participants underwent [ 11 C] Pittsburgh compound B-PET imaging to quantify Aβ deposition in the brain and blood sampling for APOE genotyping. Sleep and circadian parameters were measured using actigraphy for 8 consecutive days. The APOE ε4 allele had moderating effects on the associations of sleep latency (SL), mesor, and acrophase with cerebral Aβ deposition, and the interactions between APOE ε4 status and SL and between APOE ε4 status and acrophase remained significant after adjusting for multiple comparisons. In APOE ε4 noncarriers, shorter SL, higher mesor, and advanced acrophase were associated with Aβ positivity. In contrast, APOE ε4 carriers showed a relationship between delayed acrophase and Aβ accumulation that approached but did not reach significance. After the Bonferroni correction, the associations of shorter SL and higher mesor with Aβ positivity remained significant for APOE ε4 noncarriers. Our findings suggest that the APOE ε4 allele may act as a moderator in the relationship between the sleep-wake cycle and Aβ accumulation in CN older adults. Thus, APOE ε4 status needs to be considered as a key factor when designing related research or interventions. © 2018 American Academy of Neurology.

Armodafinil in the treatment of sleep/wake disorders

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Jonathan RL Schwartz

2010-07-01

Full Text Available Jonathan RL Schwartz1,Thomas Roth2, Chris Drake21INTEGRIS Sleep Disorders Center and University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; 2Sleep Disorders and Research Center, Henry Ford Hospital, Detroit, MI, USAAbstract: Excessive sleepiness (ES is a major but underestimated public health concern associated with significant impairments in alertness/wakefulness and significant morbidity. The term ES has been used in the sleep medicine literature for years, but due to its nonspecific symptoms (ie tiredness or fatigue, it frequently goes unrecognized or is misdiagnosed in primary care. In some cases ES arises due to poor sleep habits or self-imposed sleep deprivation; however, ES is also a key component of a number of sleep/wake disorders and multiple medical and psychiatric disorders. Identification and treatment of ES is critical to improve the quality of life and well-being of patients and for the safety of the wider community. The inability of patients to recognize the nature, extent, and symptomatic profile of sleep/wake disorders requires vigilance on the part of healthcare professionals. Interventions to address ES and its associated impairments, treatment of the underlying sleep/wake disorder, and follow-up are a priority given the potential for serious consequences if left untreated. Wakefulness-promoting agents are available that treat ES associated with sleep/wake disorders. This review examines current approaches for managing this debilitating and potentially life-threatening condition, focusing on the place of armodafinil as a wakefulness-promoting agent.Keywords: excessive sleepiness, wakefulness, armodafinil, obstructive sleep apnea, narcolepsy, shift-work disorder

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.

Trials of bright light exposure and melatonin administration in a patient with non-24 hour sleep-wake syndrome.

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Hayakawa, T; Kamei, Y; Urata, J; Shibui, K; Ozaki, S; Uchiyama, M; Okawa, M

1998-04-01

We report a patient with non-24 h sleep-wake syndrome (non-24) whose free-running sleep-wake cycle was successfully treated with both scheduled bright light exposure and melatonin treatment. In the present study, morning bright light as well as evening melatonin phase-advanced sleep-wake cycles and melatonin rhythm. Both these procedures achieved appropriate entrainment to a 24 h day. However, the patient did not continue morning bright light therapy after the discharge. Rising at appropriate times in the morning for bright light therapy was difficult for him to continue. Melatonin treatment was better tolerated because of its ease of application.

Sleep and Sleep-wake Rhythm in Older Adults with Intellectual Disabilities

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E. van de Wouw-Van Dijk (Ellen)

2013-01-01

textabstractEveryone who has experienced poor sleep knows how it affects daytime functioning and wellbeing. A good night’s rest and a stable sleep-wake rhythm are therefore very important. The sleep-wake rhythm is regulated by several brain structures. People with an intellectual disability (ID) all

[Sleep-wake cycle in chemotherapy patients: a retrospective study].

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Gonella, S

2010-06-01

Over 50% of cancer patients suffer from insomnia, nearly twice the estimated prevalence in the general population. However, this widespread problem has received far less attention compared to cancer pain and fatigue. The aim of this study was to determine whether certain factors can alter the sleep-wake cycle in this patient subgroup and whether altered nyctohemeral sleep rhythms may negatively impact on quality of life. The medical records of 101 patients treated at the Cancer Center, San Giovanni Battista Hospital, Turin, and who had died of cancer in 2007, were reviewed. Extracted from each record were data on: patient age, sex, primary tumor site, presence of pain, concomitant conditions, concomitant medications, type of therapy, chemotherapeutic (CT) scheme, survival, and side effects. The sample was divided into two subgroups defined as inducers or non-inducers, depending on whether the patient had taken medications or not to treat insomnia. Significant differences between the two groups for these variables were tested using statistical analysis. A statistically significant difference between the two groups emerged for anxiety-depression syndromes (P=0.00001), the number of sleeping pills taken in association with a concurrent anxiety-depression syndrome (P=0.01463), and side effects (P=0.0015). There was a statistically significant difference between the inducer and the non-inducer groups for female sex (one-tailed Fisher's exact test; P=0.04170) but the difference was marginal on Fisher's two-tailed test (P=0.06121). No statistically significant differences between the two groups were found for mean age (P=0.61281), median age (P=0.9996), primary tumor site, concomitant conditions (P=0.4205), survival (P=0.5704), presence of pain (P=0.53300) or type of therapy (P=0.6466). Sleep disturbances are a common complaint of cancer patients but have only recently attracted greater attention as the diagnosis of cancer has increased. Sleep disturbances are not an

Modulation of Sleep Homeostasis by Corticotropin Releasing Hormone in REM Sleep-Deprived Rats

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Ricardo Borges Machado

2010-01-01

Full Text Available Studies have shown that sleep recovery following different protocols of forced waking varies according to the level of stress inherent to each method. Sleep deprivation activates the hypothalamic-pituitary-adrenal axis and increased corticotropin-releasing hormone (CRH impairs sleep. The purpose of the present study was to evaluate how manipulations of the CRH system during the sleep deprivation period interferes with subsequent sleep rebound. Throughout 96 hours of sleep deprivation, separate groups of rats were treated i.c.v. with vehicle, CRH or with alphahelical CRH9−41, a CRH receptor blocker, twice/day, at 07:00 h and 19:00 h. Both treatments impaired sleep homeostasis, especially in regards to length of rapid eye movement sleep (REM and theta/delta ratio and induced a later decrease in NREM and REM sleep and increased waking bouts. These changes suggest that activation of the CRH system impact negatively on the homeostatic sleep response to prolonged forced waking. These results indicate that indeed, activation of the HPA axis—at least at the hypothalamic level—is capable to reduce the sleep rebound induced by sleep deprivation.

Ramadan fasting, mental health and sleep-wake pattern

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Mohsen Khoshniat Nikoo

2012-06-01

Full Text Available Background: Life style Changes during Ramadan month could possibly affect sleep-related behaviors such as total daily sleep time, sleep and wake up time and brain waves. In addition, Spirituality and religiosity have a marvelous influence on mental health and effective solutions against stress are being religious and believe in God. This review discusses the results of all related studies about possible effects of Ramadan fasting on various aspects of sleep pattern and mental health. Methods: Keywords such as ‘Ramadan’, ‘Ramadan Fasting’, ‘Islamic Fasting’, ‘Fasting in Ramadan’ and Fasting along Sleep, Chronotype, Sleep Latency, REM, NREM, Brain Wave, Psychology, Mental health, Religion, Mood, Depression, Social interaction, Depressive illness, Psychomotor performances, Bipolar disorders, Accident, Mania, Anxiety and Stress were searched via PubMed database, Scientific Information Datebas (SID and also some local journals, hence, 103 related articles from 1972 until 2010 were studied. Results: The results of studies about the effects of Ramadan fasting on sleep pattern is not similar and these differences could be due to cultural and life style discrepancy in several countries. Fasting during Ramadan could lead to delay in sleep-wake cycle, decrease in deep sleep and lack of awareness during the day. Conclusion: There are various reasons such as dietary pattern, hormonal changes and also stress which could alter the quantity and quality of sleep during Ramadan. Also, according to the available information, there is a relationship between fasting and mental health.

Why Does Sleep Slow-Wave Activity Increase After Extended Wake? Assessing the Effects of Increased Cortical Firing During Wake and Sleep.

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Rodriguez, Alexander V; Funk, Chadd M; Vyazovskiy, Vladyslav V; Nir, Yuval; Tononi, Giulio; Cirelli, Chiara

2016-12-07

During non-rapid eye movement (NREM) sleep, cortical neurons alternate between ON periods of firing and OFF periods of silence. This bi-stability, which is largely synchronous across neurons, is reflected in the EEG as slow waves. Slow-wave activity (SWA) increases with wake duration and declines homeostatically during sleep, but the underlying mechanisms remain unclear. One possibility is neuronal "fatigue": high, sustained firing in wake would force neurons to recover with more frequent and longer OFF periods during sleep. Another possibility is net synaptic potentiation during wake: stronger coupling among neurons would lead to greater synchrony and therefore higher SWA. Here, we obtained a comparable increase in sustained firing (6 h) in cortex by: (1) keeping mice awake by exposure to novel objects to promote plasticity and (2) optogenetically activating a local population of cortical neurons at wake-like levels during sleep. Sleep after extended wake led to increased SWA, higher synchrony, and more time spent OFF, with a positive correlation between SWA, synchrony, and OFF periods. Moreover, time spent OFF was correlated with cortical firing during prior wake. After local optogenetic stimulation, SWA and cortical synchrony decreased locally, time spent OFF did not change, and local SWA was not correlated with either measure. Moreover, laser-induced cortical firing was not correlated with time spent OFF afterward. Overall, these results suggest that high sustained firing per se may not be the primary determinant of SWA increases observed after extended wake. A long-standing hypothesis is that neurons fire less during slow-wave sleep to recover from the "fatigue" accrued during wake, when overall synaptic activity is higher than in sleep. This idea, however, has rarely been tested and other factors, namely increased cortical synchrony, could explain why sleep slow-wave activity (SWA) is higher after extended wake. We forced neurons in the mouse cortex to fire

Effect of sleep-wake reversal and sleep deprivation on the circadian rhythm of oxygen toxicity seizure susceptibility.

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Dexter, J. D.; Hof, D. G.; Mengel, C. E.

1972-01-01

Albino Sprague-Dawley rats were exposed in a previously O2 flushed, CO2 free chamber. The exposure began with attainment of 60 psi (gauge) and the end point was the first generalized oxygen toxicity seizure. Animals were exposed to reversal diurnal conditions since weanlings until their sleep-wake cycles had completely reversed, and then divided into four groups of 20 based on the time of day exposed. The time of exposure to oxygen at high pressure prior to seizure was now significantly longer in the group exposed from 1900 to 2000 hr and a reversal of the circadian rhythm of oxygen toxicity seizure susceptibility was noted. Animals maintained on normal diurnal conditions were deprived of sleep on the day of exposure for the 12 hours prior to exposure at 1900 hr, while controls were allowed to sleep. There was no significant differences in the time prior to seizure between the deprived animals and the controls with an n = 40. Thus the inherent threshold in susceptibility to high-pressure oxygen seizures seems not to be a function of sleep itself, but of some biochemical/physiologic event which manifests a circadian rhythm.

Circadian Sleep-Wake Rhythm of Older Adults with Intellectual Disabilities

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Maaskant, Marijke; van de Wouw, Ellen; van Wijck, Ruud; Evenhuis, Heleen M.; Echteld, Michael A.

2013-01-01

The circadian sleep-wake rhythm changes with aging, resulting in a more fragmented sleep-wake pattern. In individuals with intellectual disabilities (ID), brain structures regulating the sleep-wake rhythm might be affected. The aims of this study were to compare the sleep-wake rhythm of older adults with ID to that of older adults in the general…

Forecasting behavior in smart homes based on sleep and wake patterns.

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Williams, Jennifer A; Cook, Diane J

2017-01-01

The goal of this research is to use smart home technology to assist people who are recovering from injuries or coping with disabilities to live independently. We introduce an algorithm to model and forecast wake and sleep behaviors that are exhibited by the participant. Furthermore, we propose that sleep behavior is impacted by and can be modeled from wake behavior, and vice versa. This paper describes the Behavior Forecasting (BF) algorithm. BF consists of 1) defining numeric values that reflect sleep and wake behavior, 2) forecasting wake and sleep values from past behavior, 3) analyzing the effect of wake behavior on sleep and vice versa, and 4) improving prediction performance by using both wake and sleep scores. The BF method was evaluated with data collected from 20 smart homes. We found that regardless of the forecasting method utilized, wake behavior and sleep behavior can be modeled with a minimum accuracy of 84%. Additionally, normalizing the wake and sleep scores drastically improves the accuracy to 99%. The results show that we can effectively model wake and sleep behaviors in a smart environment. Furthermore, wake behaviors can be predicted from sleep behaviors and vice versa.

Bedtime activities, sleep environment, and sleep/wake patterns of Japanese elementary school children.

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Oka, Yasunori; Suzuki, Shuhei; Inoue, Yuich

2008-01-01

Bedtime activities, sleep environment, and their impact on sleep/wake patterns were assessed in 509 elementary school children (6-12 years of age; 252 males and 257 females). Television viewing, playing video games, and surfing the Internet had negative impact on sleep/wake parameters. Moreover, presence of a television set or video game in the child's bedroom increased their activity before bedtime. Time to return home later than 8 p.m. from after-school activity also had a negative impact on sleep/wake patterns. Health care practitioners should be aware of the potential negative impact of television, video games, and the Internet before bedtime, and also the possibility that late after-school activity can disturb sleep/wake patterns.

Forecasting Behavior in Smart Homes Based on Sleep and Wake Patterns

Science.gov (United States)

Williams, Jennifer A.; Cook, Diane J.

2017-01-01

Background The goal of this research is to use smart home technology to assist people who are recovering from injuries or coping with disabilities to live independently. Objective We introduce an algorithm to model and forecast wake and sleep behaviors that are exhibited by the participant. Furthermore, we propose that sleep behavior is impacted by and can be modeled from wake behavior, and vice versa. Methods This paper describes the Behavior Forecasting (BF) algorithm. BF consists of 1) defining numeric values that reflect sleep and wake behavior, 2) forecasting wake and sleep values from past behavior, 3) analyzing the effect of wake behavior on sleep and vice versa, and 4) improving prediction performance by using both wake and sleep scores. Results The BF method was evaluated with data collected from 20 smart homes. We found that regardless of the forecasting method utilized, wake behavior and sleep behavior can be modeled with a minimum accuracy of 84%. Additionally, normalizing the wake and sleep scores drastically improves the accuracy to 99%. Conclusions The results show that we can effectively model wake and sleep behaviors in a smart environment. Furthermore, wake behaviors can be predicted from sleep behaviors and vice versa. PMID:27689555

Voluntary Sleep Loss in Rats

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Oonk, Marcella; Krueger, James M.; Davis, Christopher J.

2016-01-01

Study Objectives: Animal sleep deprivation (SDEP), in contrast to human SDEP, is involuntary and involves repeated exposure to aversive stimuli including the inability of the animal to control the waking stimulus. Therefore, we explored intracranial self-stimulation (ICSS), an operant behavior, as a method for voluntary SDEP in rodents. Methods: Male Sprague-Dawley rats were implanted with electroencephalography/electromyography (EEG/EMG) recording electrodes and a unilateral bipolar electrode into the lateral hypothalamus. Rats were allowed to self-stimulate, or underwent gentle handling-induced SDEP (GH-SDEP), during the first 6 h of the light phase, after which they were allowed to sleep. Other rats performed the 6 h ICSS and 1 w later were subjected to 6 h of noncontingent stimulation (NCS). During NCS the individual stimulation patterns recorded during ICSS were replayed. Results: After GH-SDEP, ICSS, or NCS, time in nonrapid eye movement (NREM) sleep and rapid eye movement (REM) sleep increased. Further, in the 24 h after SDEP, rats recovered all of the REM sleep lost during SDEP, but only 75% to 80% of the NREM sleep lost, regardless of the SDEP method. The magnitude of EEG slow wave responses occurring during NREM sleep also increased after SDEP treatments. However, NREM sleep EEG slow wave activity (SWA) responses were attenuated following ICSS, compared to GH-SDEP and NCS. Conclusions: We conclude that ICSS and NCS can be used to sleep deprive rats. Changes in rebound NREM sleep EEG SWA occurring after ICSS, NCS, and GH-SDEP suggest that nonspecific effects of the SDEP procedure differentially affect recovery sleep phenotypes. Citation: Oonk M, Krueger JM, Davis CJ. Voluntary sleep loss in rats. SLEEP 2016;39(7):1467–1479. PMID:27166236

Choline acetyltransferase expression during periods of behavioral activity and across natural sleep-wake states in the basal forebrain.

Science.gov (United States)

Greco, M A; McCarley, R W; Shiromani, P J

1999-01-01

The present study examined whether the expression of the messenger RNA encoding the protein responsible for acetylcholine synthesis is associated with sleep-wakefulness. Choline acetyltransferase messenger RNA levels were analysed using a semi-quantitative assay in which reverse transcription was coupled to complementary DNA amplification using the polymerase chain reaction. To examine the relationship between steady-state messenger RNA and behavioral activity, rats were killed during the day (4.00 p.m.) or night (4.00 a.m.), and tissue from the vertical and horizontal limbs of the diagonal bands of Broca was analysed. Choline acetyltransferase messenger RNA levels were higher during the day than during the night. The second study examined more closely the association between choline acetyltransferase messenger RNA levels and individual bouts of wakefulness, slow-wave sleep or rapid eye movement sleep. Choline acetyltransferase messenger RNA levels were low during wakefulness, intermediate in slow-wave sleep and high during rapid eye movement sleep. In contrast, protein activity, measured at a projection site of cholinergic neurons of the basal forebrain, was higher during wakefulness than during sleep. These findings suggest that choline acetyltransferase protein and messenger RNA levels exhibit an inverse relationship during sleep and wakefulness. The increased messenger RNA expression during sleep is consistent with a restorative function of sleep.

Uncovering the genetic landscape for multiple sleep-wake traits.

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Christopher J Winrow

Full Text Available Despite decades of research in defining sleep-wake properties in mammals, little is known about the nature or identity of genes that regulate sleep, a fundamental behaviour that in humans occupies about one-third of the entire lifespan. While genome-wide association studies in humans and quantitative trait loci (QTL analyses in mice have identified candidate genes for an increasing number of complex traits and genetic diseases, the resources and time-consuming process necessary for obtaining detailed quantitative data have made sleep seemingly intractable to similar large-scale genomic approaches. Here we describe analysis of 20 sleep-wake traits from 269 mice from a genetically segregating population that reveals 52 significant QTL representing a minimum of 20 genomic loci. While many (28 QTL affected a particular sleep-wake trait (e.g., amount of wake across the full 24-hr day, other loci only affected a trait in the light or dark period while some loci had opposite effects on the trait during the light vs. dark. Analysis of a dataset for multiple sleep-wake traits led to previously undetected interactions (including the differential genetic control of number and duration of REM bouts, as well as possible shared genetic regulatory mechanisms for seemingly different unrelated sleep-wake traits (e.g., number of arousals and REM latency. Construction of a Bayesian network for sleep-wake traits and loci led to the identification of sub-networks of linkage not detectable in smaller data sets or limited single-trait analyses. For example, the network analyses revealed a novel chain of causal relationships between the chromosome 17@29cM QTL, total amount of wake, and duration of wake bouts in both light and dark periods that implies a mechanism whereby overall sleep need, mediated by this locus, in turn determines the length of each wake bout. Taken together, the present results reveal a complex genetic landscape underlying multiple sleep-wake traits

Traumatic brain injury and disturbed sleep and wakefulness.

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Baumann, Christian R

2012-09-01

Traumatic brain injury is a frequent condition worldwide, and sleep-wake disturbances often complicate the course after the injuring event. Current evidence suggests that the most common sleep-wake disturbances following traumatic brain injury include excessive daytime sleepiness and posttraumatic hypersomnia, that is, increased sleep need per 24 h. The neuromolecular basis of posttraumatic sleep pressure enhancement is not entirely clear. First neuropathological and clinical studies suggest that impaired hypocretin (orexin) signalling might contribute to sleepiness, but direct or indirect traumatic injury also to other sleep-wake modulating systems in the brainstem and the mesencephalon is likely. Posttraumatic insomnia may be less common than posttraumatic sleepiness, but studies on its frequency revealed conflicting results. Furthermore, insomnia is often associated with psychiatric comorbidities, and some patients with posttraumatic disruption of their circadian rhythm may be misdiagnosed as insomnia patients. The pathophysiology of posttraumatic circadian sleep disorders remains elusive; however, there is some evidence that reduced evening melatonin production due to traumatic brain damage may cause disruption of circadian regulation of sleep and wakefulness.

Seizure phenotypes, periodicity, and sleep-wake pattern of seizures in Kcna-1 null mice.

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Wright, Samantha; Wallace, Eli; Hwang, Youngdeok; Maganti, Rama

2016-02-01

This study was undertaken to describe seizure phenotypes, natural progression, sleep-wake patterns, as well as periodicity of seizures in Kcna-1 null mutant mice. These mice were implanted with epidural electroencephalography (EEG) and electromyography (EMG) electrodes, and simultaneous video-EEG recordings were obtained while animals were individually housed under either diurnal (LD) condition or constant darkness (DD) over ten days of recording. The video-EEG data were analyzed to identify electrographic and behavioral phenotypes and natural progression and to examine the periodicity of seizures. Sleep-wake patterns were analyzed to understand the distribution and onset of seizures across the sleep-wake cycle. Four electrographically and behaviorally distinct seizure types were observed. Regardless of lighting condition that animals were housed in, Kcna-1 null mice initially expressed only a few of the most severe seizure types that progressively increased in frequency and decreased in seizure severity. In addition, a circadian periodicity was noted, with seizures peaking in the first 12h of the Zeitgeber time (ZT) cycle, regardless of lighting conditions. Interestingly, seizure onset differed between lighting conditions where more seizures arose out of sleep in LD conditions, whereas under DD conditions, the majority occurred out of the wakeful state. We suggest that this model be used to understand the circadian pattern of seizures as well as the pathophysiological implications of sleep and circadian disturbances in limbic epilepsies. Copyright © 2015 Elsevier Inc. All rights reserved.

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

OpenAIRE

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

2007-01-01

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 respo...

Why Does REM Sleep Occur? A Wake-up Hypothesis

OpenAIRE

Dr. W. R. eKlemm

2011-01-01

Brain activity differs in the various sleep stages and in conscious wakefulness. Awakening from sleep requires restoration of the complex nerve impulse patterns in neuronal network assemblies necessary to re-create and sustain conscious wakefulness. Herein I propose that the brain uses REM to help wake itself up after it has had a sufficient amount of sleep. Evidence suggesting this hypothesis includes the facts that, 1) when first going to sleep, the brain plunges into Stage N3 (formerly ca...

Differential Effects of an Alpha-2 Agonist on Wakefulness and Paradoxical Sleep in The Rat: A Polygraphic and Biochemical Approach

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Z. de Saint Hilaire

1997-01-01

Full Text Available The purpose of this experiment was to determine the sensitivity of wakefulness and paradoxical sleep to the α2-agonist, c1onidine. The drug inhibited both wakefulness and paradoxical sleep but the smallest dose necessary to inhibit wakefulness was 64 times larger than the smallest dose inhibiting paradoxical sleep. The effect on paradoxical sleep was inhibitory for all the clonidine doses but wakefulness was enhanced transiently after the four largest doses used. The time between injection and maximum wakefulness enhancement was highly correlated with the dose of c1onidine. The brain level measured after these four different doses at the moment of maximum wakefulness enhancement was the same, suggesting that this effect occurred only when a critical concentration of the drug was attained in the brain and not when the concentration was higher or lower. These data suggest that different α2-adrenoceptors are involved in these two states of vigilance or, alternatively, that their sensitivity is modulated physiologically. In addition, a sensitivity imbalance between different α2-adrenoceptors may exist in wakefulness but not in paradoxical sleep.

Acid reflux directly causes sleep disturbances in rat with chronic esophagitis.

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Nakahara, Kenichi; Fujiwara, Yasuhiro; Tsukahara, Takuya; Yamagami, Hirokazu; Tanigawa, Tetsuya; Shiba, Masatsugu; Tominaga, Kazunari; Watanabe, Toshio; Urade, Yoshihiro; Arakawa, Tetsuo

2014-01-01

Gastroesophageal reflux disease (GERD) is strongly associated with sleep disturbances. Proton pump inhibitor (PPI) therapy improves subjective but not objective sleep parameters in patients with GERD. This study aimed to investigate the association between GERD and sleep, and the effect of PPI on sleep by using a rat model of chronic acid reflux esophagitis. Acid reflux esophagitis was induced by ligating the transitional region between the forestomach and the glandular portion and then wrapping the duodenum near the pylorus. Rats underwent surgery for implantation of electrodes for electroencephalogram and electromyogram recordings, and they were transferred to a soundproof recording chamber. Polygraphic recordings were scored by using 10-s epochs for wake, rapid eye movement sleep, and non-rapid eye movement (NREM) sleep. To examine the role of acid reflux, rats were subcutaneously administered a PPI, omeprazole, at a dose of 20 mg/kg once daily. Rats with reflux esophagitis presented with several erosions, ulcers, and mucosal thickening with basal hyperplasia and marked inflammatory infiltration. The reflux esophagitis group showed a 34.0% increase in wake (232.2±11.4 min and 173.3±7.4 min in the reflux esophagitis and control groups, respectively; preflux esophagitis, and this effect was not observed when the PPI was withdrawn. Acid reflux directly causes sleep disturbances in rats with chronic esophagitis.

Padrão do ciclo sono-vigília e sua relação com a ansiedade em estudantes universitários Sleep/wake cycle pattern and its relationship with anxiety in college students

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Katie Moraes de Almondes

2003-04-01

Full Text Available Neste trabalho, foram investigadas as relações entre o ciclo sono-vigília e a ansiedade. O ciclo sono-vigília e traço e estado de ansiedade foram avaliados em 37 estudantes do segundo ano do curso médico. Os estudantes responderam ao Índice de Qualidade de Sono de Pittsburgh - IQSP, ao Inventário de Estado e Traço de Ansiedade - IDATE e a um questionário de matutinidade - vespertinidade (cronotipo. Todos registraram seu sono em um diário durante duas semanas. Os resultados mostraram que os estudantes de medicina tinham altos escores de traço e estado de ansiedade. Aqueles que tinham maiores escores de traço de ansiedade acordavam mais cedo nos dias de semana e finais de semana enquanto os que apresentavam irregularidade do seu ciclo sono-vigília apresentaram maior estado de ansiedade. Sugere-se que há uma relação entre o ciclo sono-vigília e a ansiedade.This paper examines the relationship between the sleep/wake cycle and anxiety in medical students. The sleep/wake cycle and anxiety were evaluated in 37 second year medical school students. The volunteers answered a morningness-eveningness questionnaire, Pittsburgh Sleep Quality Index - PSQI and state and trait of anxiety inventory - STAI; all kept a sleep/wake diary for two weeks. The results showed that the students had high anxiety trait and state. Students who had high anxiety trait had an earlier sleep offset on weekdays and weekend, and students who displayed irregularity in the sleep/wake cycle had high anxiety state. These results suggest a relationship between the sleep/wake cycle and anxiety.

A three states sleep-waking model

International Nuclear Information System (INIS)

Comte, J.C.; Schatzman, M.; Ravassard, P.; Luppi, P.H.; Salin, P.A.

2006-01-01

The mechanisms underlying the sleep-states periodicity in animals are a mystery of biology. Recent studies identified a new neuronal population activated during the slow wave sleep (SWS) in the ventral lateral preoptic area of the hypothalamus. Interactions between this neuronal population and the others populations implicated in the vigilance states (paradoxical sleep (PS) and wake (W)) dynamics are not determined. Thus, we propose here a sleep-waking theoretical model that depicts the potential interactions between the neuronal populations responsible for the three vigilance states. First, we pooled data from previous papers regarding the neuronal populations firing rate time course and characterized statistically the experimental hypnograms. Then, we constructed a nonlinear differential equations system describing the neuronal populations activity time course. A simple rule playing the firing threshold role applied to the model allows to construct a theoretical hypnogram. A random modulation of the neuronal activity, shows that theoretical hypnograms present a dynamics close to the experimental observations. Furthermore, we show that the wake promoting neurons activity can predict the next SWS episode duration

Acid reflux directly causes sleep disturbances in rat with chronic esophagitis.

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Kenichi Nakahara

Full Text Available BACKGROUND & AIMS: Gastroesophageal reflux disease (GERD is strongly associated with sleep disturbances. Proton pump inhibitor (PPI therapy improves subjective but not objective sleep parameters in patients with GERD. This study aimed to investigate the association between GERD and sleep, and the effect of PPI on sleep by using a rat model of chronic acid reflux esophagitis. METHODS: Acid reflux esophagitis was induced by ligating the transitional region between the forestomach and the glandular portion and then wrapping the duodenum near the pylorus. Rats underwent surgery for implantation of electrodes for electroencephalogram and electromyogram recordings, and they were transferred to a soundproof recording chamber. Polygraphic recordings were scored by using 10-s epochs for wake, rapid eye movement sleep, and non-rapid eye movement (NREM sleep. To examine the role of acid reflux, rats were subcutaneously administered a PPI, omeprazole, at a dose of 20 mg/kg once daily. RESULTS: Rats with reflux esophagitis presented with several erosions, ulcers, and mucosal thickening with basal hyperplasia and marked inflammatory infiltration. The reflux esophagitis group showed a 34.0% increase in wake (232.2±11.4 min and 173.3±7.4 min in the reflux esophagitis and control groups, respectively; p<0.01 accompanied by a reduction in NREM sleep during light period, an increase in sleep fragmentation, and more frequent stage transitions. The use of omeprazole significantly improved sleep disturbances caused by reflux esophagitis, and this effect was not observed when the PPI was withdrawn. CONCLUSIONS: Acid reflux directly causes sleep disturbances in rats with chronic esophagitis.

Hypocretin/orexin antagonism enhances sleep-related adenosine and GABA neurotransmission in rat basal forebrain.

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Vazquez-DeRose, Jacqueline; Schwartz, Michael D; Nguyen, Alexander T; Warrier, Deepti R; Gulati, Srishti; Mathew, Thomas K; Neylan, Thomas C; Kilduff, Thomas S

2016-03-01

Hypocretin/orexin (HCRT) neurons provide excitatory input to wake-promoting brain regions including the basal forebrain (BF). The dual HCRT receptor antagonist almorexant (ALM) decreases waking and increases sleep. We hypothesized that HCRT antagonists induce sleep, in part, through disfacilitation of BF neurons; consequently, ALM should have reduced efficacy in BF-lesioned (BFx) animals. To test this hypothesis, rats were given bilateral IgG-192-saporin injections, which predominantly targets cholinergic BF neurons. BFx and intact rats were then given oral ALM, the benzodiazepine agonist zolpidem (ZOL) or vehicle (VEH) at lights-out. ALM was less effective than ZOL at inducing sleep in BFx rats compared to controls. BF adenosine (ADO), γ-amino-butyric acid (GABA), and glutamate levels were then determined via microdialysis from intact, freely behaving rats following oral ALM, ZOL or VEH. ALM increased BF ADO and GABA levels during waking and mixed vigilance states, and preserved sleep-associated increases in GABA under low and high sleep pressure conditions. ALM infusion into the BF also enhanced cortical ADO release, demonstrating that HCRT input is critical for ADO signaling in the BF. In contrast, oral ZOL and BF-infused ZOL had no effect on ADO levels in either BF or cortex. ALM increased BF ADO (an endogenous sleep-promoting substance) and GABA (which is increased during normal sleep), and required an intact BF for maximal efficacy, whereas ZOL blocked sleep-associated BF GABA release, and required no functional contribution from the BF to induce sleep. ALM thus induces sleep by facilitating the neural mechanisms underlying the normal transition to sleep.

Neurological impairments and sleep-wake behaviour among the mentally retarded.

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Lindblom, N; Heiskala, H; Kaski, M; Leinonen, L; Nevanlinna, A; Iivanainen, M; Laakso, M L

2001-12-01

The objective of the present study was to evaluate the relationship between the sleep-wake behaviour and neurological impairments among mentally retarded people. The sleep-wake behaviour of 293 mentally retarded subjects living in a rehabilitation center was studied by a standardized observation protocol carried out by trained staff members. The protocol consisted of brief check-ups of the subjects' sleep-wake status at 20-min intervals for five randomly chosen 24-h periods during 4 months. From the raw data five sleep-wake behaviour variables were formed. The data concerning the subject characteristics (age, body mass index (BMI), gender, degree of mental retardation, presence of locomotor disability, that of epilepsy, blindness or deafness and the usage of psychotropic medications) were collected from the medical records. Two main findings emerged: (1) severe locomotor disability, blindness and active epilepsy were found to be independent predictors of increased daytime sleep and increased number of wake-sleep transitions and (2) the subjects with a combination of two or all three of these impairments had a significantly more fragmented and abnormally distributed sleep than those with none or milder forms of these impairments. Age, BMI, degree of mental retardation and the studied medications played a minor role in the sleep disturbances of the study population. Finally, deafness was not found to be associated with any of the measured sleep-wake variables.

Multisite accelerometry for sleep and wake classification in children.

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Lamprecht, Marnie L; Bradley, Andrew P; Tran, Tommy; Boynton, Alison; Terrill, Philip I

2015-01-01

Actigraphy is a useful alternative to the gold standard polysomnogram for non-invasively measuring sleep and wakefulness. However, it is unable to accurately assess sleep fragmentation due to its inability to differentiate restless sleep from wakefulness and quiet wake from sleep. This presents significant limitations in the assessment of sleep-related breathing disorders where sleep fragmentation is a common symptom. We propose that this limitation may be caused by hardware constraints and movement representation techniques. Our objective was to determine if multisite tri-axial accelerometry improves sleep and wake classification. Twenty-four patients aged 6-15 years (median: 8 years, 16 male) underwent a diagnostic polysomnogram while simultaneously recording motion from the left wrist and index fingertip, upper thorax and left ankle and great toe using a custom accelerometry system. Movement was quantified using several features and two feature selection techniques were employed to select optimal features for restricted feature set sizes. A heuristic was also applied to identify movements during restless sleep. The sleep and wake classification performance was then assessed and validated against the manually scored polysomnogram using discriminant analysis. Tri-axial accelerometry measured at the wrist significantly improved the wake detection when compared to uni-axial accelerometry (specificity at 85% sensitivity: 71.3(14.2)% versus 55.2(24.7)%, p < 0.01). Multisite accelerometry significantly improved the performance when compared to the single wrist placement (specificity at 85% sensitivity: 82.1(12.5)% versus 71.3(14.2)%, p < 0.05). Our results indicate that multisite accelerometry offers a significant performance benefit which could be further improved by analysing movement in raw multisite accelerometry data.

Neuropeptide glutamic acid-isoleucine (NEI)-induced paradoxical sleep in rats.

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Fujimoto, Moe; Fukuda, Satoru; Sakamoto, Hidetoshi; Takata, Junko; Sawamura, Shigehito

2017-01-01

Neuropeptideglutamic acid-isoleucine (NEI) as well as melanin concentrating hormone (MCH) is cleaved from the 165 amino acid protein, prepro-melanin concentrating hormone (prepro-MCH). Among many physiological roles of MCH, we demonstrated that intracerebroventricular (icv) injection of MCH induced increases in REM sleep episodes as well as in non REM sleep episodes. However, there are no studies on the effect of NEI on the sleep-wake cycle. As for the sites of action of MCH for induction of REM sleep, the ventrolateral periaqueductal gray (vlPAG) has been reported to be one of its site of action. Although MCH neurons contain NEI, GABA, MCH, and other neuropeptides, we do not know which transmitter(s) might induce REM sleep by acting on the vlPAG. Thus, we first examined the effect of icv injection of NEI on the sleep-wake cycle, and investigated how microinjection of either NEI, MCH, or GABA into the vlPAG affected REM sleep in rats. Icv injection of NEI (0.61μg/5μl: n=7) significantly increased the time spent in REM episodes compared to control (saline: 5μl; n=6). Microinjection of either NEI (61ng/0.2μl: n=7), MCH (100ng/0.2μl: n=6) or GABA (250mM/0.2μl: n=7) into the vlPAG significantly increased the time spent in REM episodes and the AUC. Precise hourly analysis of REM sleep also revealed that after those microinjections, NEI and MCH increased REM episodes at the latter phase, compared to GABA which increased REM episodes at the earlier phase. This result suggests that NEI and MCH may induce sustained REM sleep, while GABA may initiate REM sleep. In conclusion, our findings demonstrate that NEI, a cleaved peptide from the same precursor, prepro-MCH, as MCH, induce REM sleep at least in part through acting on the vlPAG. Copyright © 2016 Elsevier Inc. All rights reserved.

The sleep–wake cycle and Alzheimer’s disease: what do we know?

OpenAIRE

Lim, Miranda M.; Gerstner, Jason R.; Holtzman, David M.

2014-01-01

Sleep–wake disturbances are a highly prevalent and often disabling feature of Alzheimer’s disease (AD). A cardinal feature of AD includes the formation of amyloid plaques, associated with the extracellular accumulation of the amyloid-β (Aβ) peptide. Evidence from animal and human studies suggests that Aβ pathology may disrupt the sleep–wake cycle, in that as Aβ accumulates, more sleep–wake fragmentation develops. Furthermore, recent research in animal and human studies suggests that the sleep...

Sleep patterning changes in a prenatal stress model of depression

DEFF Research Database (Denmark)

Sickmann, Helle Mark; Skoven, C; Bastlund, Jesper F

2018-01-01

/wakefulness behavior around the change from light-to-dark phase. Control and PNS Sprague-Dawley rats were implanted with electrodes for continuous monitoring of electroencephalic activity used to determine behavioral state. The distribution of slow-wave sleep (SWS), rapid eye movement sleep (REMS) and wakefulness......Clinical depression is accompanied by changes in sleep patterning, which is controlled in a circadian fashion. It is thus desirable that animal models of depression mirror such diurnally-specific state alterations, along with other behavioral and physiological changes. We previously found several...... changes in behavior indicative of a depression-like phenotype in offspring of rats subjected to repeated, variable prenatal stress (PNS), including increased locomotor activity during specific periods of the circadian cycle. We, therefore, investigated whether PNS rats also exhibit alterations in sleep...

Why Does Rem Sleep Occur? A Wake-Up Hypothesis 1

OpenAIRE

Klemm, W. R.

2011-01-01

Brain activity differs in the various sleep stages and in conscious wakefulness. Awakening from sleep requires restoration of the complex nerve impulse patterns in neuronal network assemblies necessary to re-create and sustain conscious wakefulness. Herein I propose that the brain uses rapid eye movement (REM) to help wake itself up after it has had a sufficient amount of sleep. Evidence suggesting this hypothesis includes the facts that, (1) when first going to sleep, the brain plunges into ...

Changes in the composition of brain interstitial ions control the sleep-wake cycle

DEFF Research Database (Denmark)

Ding, Fengfei; O'Donnell, John; Xu, Qiwu

2016-01-01

, and [H+]e as well as the extracellular volume. Local cortical activity of sleeping mice could be readily converted to the stereotypical electroencephalography pattern of wakefulness by simply imposing a change in the extracellular ion composition. Thus, extracellular ions control the state...

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.

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.

Effects of GF-015535-00, a novel α1 GABA A receptor ligand, on the sleep-wake cycle in mice, with reference to zolpidem.

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Anaclet, Christelle; Zhang, Mei; Zhao, Chunmei; Buda, Colette; Seugnet, Laurent; Lin, Jian-Sheng

2012-01-01

Novel, safe, and efficient hypnotic compounds capable of enhancing physiological sleep are still in great demand in the therapy of insomnia. This study compares the sleep-wake effects of a new α1 GABA(A) receptor subunit ligand, GF-015535-00, with those of zolpidem, the widely utilized hypnotic compound. Nine C57Bl6/J male mice were chronically implanted with electrodes for EEG and sleep-wake monitoring. Each mouse received 3 doses of GF-015535-00 and zolpidem. Time spent in sleep-wake states and cortical EEG power spectra were analyzed. Both zolpidem and GF-015535-00 prominently enhanced slow wave sleep and paradoxical sleep in the mouse. However, as compared with zolpidem, GF-015535-00 showed several important differences: (1) a comparable sleep-enhancing effect was obtained with a 10 fold smaller dose; (2) the induced sleep was less fragmented; (3) the risk of subsequent wake rebound was less prominent; and (4) the cortical EEG power ratio between slow wave sleep and wake was similar to that of natural sleep and thus compatible with physiological sleep. The characteristics of the sleep-wake effects of GF-015535-00 in mice could be potentially beneficial for its use as a therapeutic compound in the treatment of insomnia. Further investigations are required to assess whether the same characteristics are conserved in other animal models and humans.

Sleeping dendrites: fiber-optic measurements of dendritic calcium activity in freely moving and sleeping animals

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Julie Seibt

2014-03-01

Full Text Available Dendrites are the post-synaptic sites of most excitatory and inhibitory synapses in the brain, making them the main location of cortical information processing and synaptic plasticity. Although current hypotheses suggest a central role for sleep in proper cognitive function and brain plasticity, virtually nothing is known about changes in dendritic activity across the sleep-wake cycle and how waking experience modifies this activity. To start addressing these questions, we developed a method that allows long-term recordings of EEGs/EMG combined with in vivo cortical calcium (Ca2+ activity in freely moving and sleeping rats. We measured Ca2+ activity from populations of dendrites of layer (L 5 pyramidal neurons (n = 13 rats that we compared with Ca2+ activity from populations of neurons in L2/3 (n = 11 rats. L5 and L2/3 neurons were labelled using bolus injection of OGB1-AM or GCaMP6 (1. Ca2+ signals were detected using a fiber-optic system (cannula diameter = 400µm, transmitting the changes in fluorescence to a photodiode. Ca2+ fluctuations could then be correlated with ongoing changes in brain oscillatory activity during 5 major brain states: active wake [AW], quiet wake [QW], NREM, REM and NREM-REM transition (or intermediate state, [IS]. Our Ca2+ recordings show large transients in L5 dendrites and L2/3 neurons that oscillate predominantly at frequencies In summary, we show that this technique is successful in monitoring fluctuations in ongoing dendritic Ca2+ activity during natural brain states and allows, in principle, to combine behavioral measurement with imaging from various brain regions (e.g. deep structures in freely behaving animals. Using this method, we show that Ca2+ transients from populations of L2/3 neurons and L5 dendrites are deferentially regulated across the sleep/wake cycle, with dendritic activity being the highest during the IS sleep. Our correlation analysis suggests that specific sleep EEG activity during NREM and IS

Neonatal Sleep-Wake Analyses Predict 18-month Neurodevelopmental Outcomes.

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Shellhaas, Renée A; Burns, Joseph W; Hassan, Fauziya; Carlson, Martha D; Barks, John D E; Chervin, Ronald D

2017-11-01

The neurological examination of critically ill neonates is largely limited to reflexive behavior. The exam often ignores sleep-wake physiology that may reflect brain integrity and influence long-term outcomes. We assessed whether polysomnography and concurrent cerebral near-infrared spectroscopy (NIRS) might improve prediction of 18-month neurodevelopmental outcomes. Term newborns with suspected seizures underwent standardized neurologic examinations to generate Thompson scores and had 12-hour bedside polysomnography with concurrent cerebral NIRS. For each infant, the distribution of sleep-wake stages and electroencephalogram delta power were computed. NIRS-derived fractional tissue oxygen extraction (FTOE) was calculated across sleep-wake stages. At age 18-22 months, surviving participants were evaluated with Bayley Scales of Infant Development (Bayley-III), 3rd edition. Twenty-nine participants completed Bayley-III. Increased newborn time in quiet sleep predicted worse 18-month cognitive and motor scores (robust regression models, adjusted r2 = 0.22, p = .007, and 0.27, .004, respectively). Decreased 0.5-2 Hz electroencephalograph (EEG) power during quiet sleep predicted worse 18-month language and motor scores (adjusted r2 = 0.25, p = .0005, and 0.33, .001, respectively). Predictive values remained significant after adjustment for neonatal Thompson scores or exposure to phenobarbital. Similarly, an attenuated difference in FTOE, between neonatal wakefulness and quiet sleep, predicted worse 18-month cognitive, language, and motor scores in adjusted analyses (each p sleep-as quantified by increased time in quiet sleep, lower electroencephalogram delta power during that stage, and muted differences in FTOE between quiet sleep and wakefulness-may improve prediction of adverse long-term outcomes for newborns with neurological dysfunction. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved

Sleep/Wake Patterns and Parental Perceptions of Sleep in Children Born Preterm

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Biggs, Sarah N.; Meltzer, Lisa J.; Tapia, Ignacio E.; Traylor, Joel; Nixon, Gillian M.; Horne, Rosemary S.C.; Doyle, Lex W.; Asztalos, Elizabeth; Mindell, Jodi A.; Marcus, Carole L.

2016-01-01

Study Objectives: To compare sleep/wake patterns in children born preterm in Australia vs Canada and determine cultural differences in the relationship between parental perception of sleep and actual sleep behaviors. Methods: Australian and Canadian children born preterm were recruited from the Caffeine for Apnea of Prematurity trial (n = 188, 5–12 y) and underwent 14 days actigraphy monitoring. Parents completed the National Sleep Foundation 2004 Sleep in America questionnaire. Cross-cultural differences in sleep characteristics assessed by actigraphy and parent-reported questionnaire were examined. Correlational analyses determined the associations between parental perceptions of child sleep need and sleep behavior. Results: Actigraphy showed preterm children obtained, on average, 8 h sleep/night, one hour less than population recommendations for their age. There was no difference in total sleep time (TST) between Australian and Canadian cohorts; however, bed and wake times were earlier in Australian children. Bedtimes and TST varied by 60 minutes from night to night in both cohorts. Parent-reported child TST on the National Sleep Foundation questionnaire was 90 minutes longer than recorded by actigraphy. Both bedtime and TST on weekdays and weekends were related to parental perception of child sleep need in the Australian cohort. Only TST on weekdays was related to parental perception of child sleep need in the Canadian cohort. Conclusions: This study suggests that short sleep duration and irregular sleep schedules are common in children born preterm. Cultural differences in the association between parental perception of child sleep need and actual sleep behaviors provide important targets for future sleep health education. Citation: Biggs SN, Meltzer LJ, Tapia IE, Traylor J, Nixon GM, Horne RS, Doyle LW, Asztalos E, Mindell JA, Marcus CL. Sleep/wake patterns and parental perceptions of sleep in children born preterm. J Clin Sleep Med 2016;12(5):711–717

Proton Pump Inhibition Increases Rapid Eye Movement Sleep in the Rat

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Munazah Fazal Qureshi

2014-01-01

Full Text Available Increased bodily CO2 concentration alters cellular pH as well as sleep. The proton pump, which plays an important role in the homeostatic regulation of cellular pH, therefore, may modulate sleep. We investigated the effects of the proton pump inhibitor “lansoprazole” on sleep-wakefulness. Male Wistar rats were surgically prepared for chronic polysomnographic recordings. Two different doses of lansoprazole (low: 1 mg/kg; high: 10 mg/kg were injected intraperitoneally in the same animal (n=7 and sleep-wakefulness was recorded for 6 hrs. The changes in sleep-wakefulness were compared statistically. Percent REM sleep amount in the vehicle and lansoprazole low dose groups was 9.26±1.03 and 9.09±0.54, respectively, which increased significantly in the lansoprazole high dose group by 31.75% (from vehicle and 34.21% (from low dose. Also, REM sleep episode numbers significantly increased in lansoprazole high dose group. Further, the sodium-hydrogen exchanger blocker “amiloride” (10 mg/kg; i.p. (n=5 did not alter sleep-wake architecture. Our results suggest that the proton pump plays an important role in REM sleep modulation and supports our view that REM sleep might act as a sentinel to help maintain normal CO2 level for unperturbed sleep.

Assessment of the Potential Role of Tryptophan as the Precursor of Serotonin and Melatonin for the Aged Sleep-wake Cycle and Immune Function: as a Model

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Sergio D. Paredes

2009-01-01

Full Text Available In the present review we summarize the relationship between the amino acid, tryptophan, the neurotransmitter, serotonin, and the indole, melatonin, with the rhythms of sleep/wake and the immune response along with the possible connections between the alterations in these rhythms due to aging and the so-called “serotonin and melatonin deficiency state.” The decrease associated with aging of the brain and circulating levels of serotonin and melatonin seemingly contributes to the alterations of both the sleep/wake cycle and the immune response that typically accompany old age. The supplemental administration of tryptophan, e.g. the inclusion of tryptophan-enriched food in the diet, might help to remediate these age-related alterations due to its capacity of raise the serotonin and melatonin levels in the brain and blood. Herein, we also summarize a set of studies related to the potential role that tryptophan, and its derived product melatonin, may play in the restoration of the aged circadian rhythms of sleep/wake and immune response, taking the ringdove ( Streptopelia risoria as a suitable model.

Mathematical models for sleep-wake dynamics: comparison of the two-process model and a mutual inhibition neuronal model.

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Anne C Skeldon

Full Text Available Sleep is essential for the maintenance of the brain and the body, yet many features of sleep are poorly understood and mathematical models are an important tool for probing proposed biological mechanisms. The most well-known mathematical model of sleep regulation, the two-process model, models the sleep-wake cycle by two oscillators: a circadian oscillator and a homeostatic oscillator. An alternative, more recent, model considers the mutual inhibition of sleep promoting neurons and the ascending arousal system regulated by homeostatic and circadian processes. Here we show there are fundamental similarities between these two models. The implications are illustrated with two important sleep-wake phenomena. Firstly, we show that in the two-process model, transitions between different numbers of daily sleep episodes can be classified as grazing bifurcations. This provides the theoretical underpinning for numerical results showing that the sleep patterns of many mammals can be explained by the mutual inhibition model. Secondly, we show that when sleep deprivation disrupts the sleep-wake cycle, ostensibly different measures of sleepiness in the two models are closely related. The demonstration of the mathematical similarities of the two models is valuable because not only does it allow some features of the two-process model to be interpreted physiologically but it also means that knowledge gained from study of the two-process model can be used to inform understanding of the behaviour of the mutual inhibition model. This is important because the mutual inhibition model and its extensions are increasingly being used as a tool to understand a diverse range of sleep-wake phenomena such as the design of optimal shift-patterns, yet the values it uses for parameters associated with the circadian and homeostatic processes are very different from those that have been experimentally measured in the context of the two-process model.

A Framework for Quantitative Modeling of Neural Circuits Involved in Sleep-to-Wake Transition

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Siamak eSorooshyari

2015-02-01

Full Text Available Identifying the neuronal circuits and dynamics of sleep-to-wake transition is essential to understanding brain regulation of behavioral states, including sleep-wake cycles, arousal, and hyperarousal. Recent work by different laboratories has used optogenetics to determine the role of individual neuromodulators in state transitions. The optogenetically-driven data does not yet provide a multi-dimensional schematic of the mechanisms underlying changes in vigilance states. This work presents a modeling framework to interpret, assist, and drive research on the sleep-regulatory network. We identify feedback, redundancy, and gating hierarchy as three fundamental aspects of this model. The presented model is expected to expand as additional data on the contribution of each transmitter to a vigilance state becomes available. Incorporation of conductance-based models of neuronal ensembles into this model and existing models of cortical excitability will provide more comprehensive insight into sleep dynamics as well as sleep and arousal-related disorders.

Why Does REM Sleep Occur? A Wake-up Hypothesis

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Dr. W. R. eKlemm

2011-09-01

Full Text Available Brain activity differs in the various sleep stages and in conscious wakefulness. Awakening from sleep requires restoration of the complex nerve impulse patterns in neuronal network assemblies necessary to re-create and sustain conscious wakefulness. Herein I propose that the brain uses REM to help wake itself up after it has had a sufficient amount of sleep. Evidence suggesting this hypothesis includes the facts that, 1 when first going to sleep, the brain plunges into Stage N3 (formerly called Stage IV, a deep abyss of sleep, and, as the night progresses, the sleep is punctuated by episodes of REM that become longer and more frequent toward morning, 2 conscious-like dreams are a reliable component of the REM state in which the dreamer is an active mental observer or agent in the dream, 3 the last awakening during a night’s sleep usually occurs in a REM episode during or at the end of a dream, 4 both REM and awake consciousness seem to arise out of a similar brainstem ascending arousal system 5 N3 is a functionally perturbed state that eventually must be corrected so that embodied brain can direct adaptive behavior, and 6 corticofugal projections to brainstem arousal areas provide a way to trigger increased cortical activity in REM to progressively raise the sleeping brain to the threshold required for wakefulness. This paper shows how the hypothesis conforms to common experience and has substantial predictive and explanatory power regarding the phenomenology of sleep in terms of ontogeny, aging, phylogeny, abnormal/disease states, cognition, and behavioral physiology. That broad range of consistency is not matched by competing theories, which are summarized herein. Specific ways to test this wake-up hypothesis are suggested. Such research could lead to a better understanding of awake consciousness.

Why does rem sleep occur? A wake-up hypothesis.

Science.gov (United States)

Klemm, W R

2011-01-01

Brain activity differs in the various sleep stages and in conscious wakefulness. Awakening from sleep requires restoration of the complex nerve impulse patterns in neuronal network assemblies necessary to re-create and sustain conscious wakefulness. Herein I propose that the brain uses rapid eye movement (REM) to help wake itself up after it has had a sufficient amount of sleep. Evidence suggesting this hypothesis includes the facts that, (1) when first going to sleep, the brain plunges into Stage N3 (formerly called Stage IV), a deep abyss of sleep, and, as the night progresses, the sleep is punctuated by episodes of REM that become longer and more frequent toward morning, (2) conscious-like dreams are a reliable component of the REM state in which the dreamer is an active mental observer or agent in the dream, (3) the last awakening during a night's sleep usually occurs in a REM episode during or at the end of a dream, (4) both REM and awake consciousness seem to arise out of a similar brainstem ascending arousal system (5) N3 is a functionally perturbed state that eventually must be corrected so that embodied brain can direct adaptive behavior, and (6) cortico-fugal projections to brainstem arousal areas provide a way to trigger increased cortical activity in REM to progressively raise the sleeping brain to the threshold required for wakefulness. This paper shows how the hypothesis conforms to common experience and has substantial predictive and explanatory power regarding the phenomenology of sleep in terms of ontogeny, aging, phylogeny, abnormal/disease states, cognition, and behavioral physiology. That broad range of consistency is not matched by competing theories, which are summarized herein. Specific ways to test this wake-up hypothesis are suggested. Such research could lead to a better understanding of awake consciousness.

The 5-HT6 receptor antagonist idalopirdine potentiates the effects of donepezil on gamma oscillations in the frontal cortex of anesthetized and awake rats without affecting sleep-wake architecture.

Science.gov (United States)

Amat-Foraster, Maria; Leiser, Steven C; Herrik, Kjartan F; Richard, Nelly; Agerskov, Claus; Bundgaard, Christoffer; Bastlund, Jesper F; de Jong, Inge E M

2017-02-01

The 5-HT 6 receptor is a promising target for cognitive disorders, in particular for Alzheimer's disease (AD). The high affinity and selective 5-HT 6 receptor antagonist idalopirdine (Lu AE58054) is currently in development for mild-moderate AD as adjunct therapy to acetylcholinesterase inhibitors (AChEIs). We studied the effects of idalopirdine alone and in combination with the AChEI donepezil on cortical function using two in vivo electrophysiological methods. Neuronal network oscillations in the frontal cortex were measured during electrical stimulation of the brainstem nucleus pontis oralis (nPO) in the anesthetized rat and by an electroencephalogram (EEG) in the awake, freely moving rat. In conjunction with the EEG study, we investigated the effects of idalopirdine and donepezil on sleep-wake architecture using telemetric polysomnography. Idalopirdine (2 mg/kg i.v.) increased gamma power in the medial prefrontal cortex (mPFC) during nPO stimulation. Donepezil (0.3 and 1 mg/kg i.v.) also increased cortical gamma power and pretreatment with idalopirdine (2 mg/kg i.v.) potentiated and prolonged the effects of donepezil. Similarly, donepezil (1 and 3 mg/kg s.c.) dose-dependently increased frontal cortical gamma power in the freely moving rat and pretreatment with idalopirdine (10 mg/kg p.o.) augmented the effect of donepezil 1 mg/kg. Analysis of the sleep-wake architecture showed that donepezil (1 and 3 mg/kg s.c.) dose-dependently delayed sleep onset and decreased the time spent in both REM and non REM sleep stages. In contrast, idalopirdine (10 mg/kg p.o.) did not affect sleep-wake architecture nor the effects of donepezil. In summary, we show that idalopirdine potentiates the effects of donepezil on frontal cortical gamma oscillations, a pharmacodynamic biomarker associated with cognition, without modifying the effects of donepezil on sleep. The increased cortical excitability may contribute to the procognitive effects of idalopirdine in donepezil

Respiratory flow-sound relationship during both wakefulness and sleep and its variation in relation to sleep apnea.

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Yadollahi, Azadeh; Montazeri, Aman; Azarbarzin, Ali; Moussavi, Zahra

2013-03-01

Tracheal respiratory sound analysis is a simple and non-invasive way to study the pathophysiology of the upper airway and has recently been used for acoustic estimation of respiratory flow and sleep apnea diagnosis. However in none of the previous studies was the respiratory flow-sound relationship studied in people with obstructive sleep apnea (OSA), nor during sleep. In this study, we recorded tracheal sound, respiratory flow, and head position from eight non-OSA and 10 OSA individuals during sleep and wakefulness. We compared the flow-sound relationship and variations in model parameters from wakefulness to sleep within and between the two groups. The results show that during both wakefulness and sleep, flow-sound relationship follows a power law but with different parameters. Furthermore, the variations in model parameters may be representative of the OSA pathology. The other objective of this study was to examine the accuracy of respiratory flow estimation algorithms during sleep: we investigated two approaches for calibrating the model parameters using the known data recorded during either wakefulness or sleep. The results show that the acoustical respiratory flow estimation parameters change from wakefulness to sleep. Therefore, if the model is calibrated using wakefulness data, although the estimated respiratory flow follows the relative variations of the real flow, the quantitative flow estimation error would be high during sleep. On the other hand, when the calibration parameters are extracted from tracheal sound and respiratory flow recordings during sleep, the respiratory flow estimation error is less than 10%.

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.

Behavioural effects of dimethyl sulfoxide (DMSO): changes in sleep architecture in rats.

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Cavas, María; Beltrán, David; Navarro, José F

2005-07-04

Dimethyl sulfoxide (DMSO) is an efficient solvent for water-insoluble compounds, widely used in biological studies and as a vehicle for drug therapy, but few data on its neurotoxic or behavioural effects is available. The aim of this work is to explore DMSO's effects upon sleep/wake states. Twenty male rats were sterotaxically prepared for polysomnography. Four concentrations of DMSO (5%, 10%, 15%, and 20%, in saline) were examined. DMSO or saline were administered intraperitoneally at the beginning of the light period. Three hours of polygraphic recording were evaluated for stages of vigilance after treatment. Sleep/wake parameters and EEG power spectral analyses during sleep were investigated. Results show no significant effect after 5% or 10% DMSO treatment. DMSO 15% increased mean episode duration of light slow wave sleep (SWS), decreasing mean episode duration of deep SWS and of quiet wake (QW). DMSO 20% increased light SWS enhancing number of episodes, while decreased deep SWS mean episode duration. EEG power spectra of sigma and delta activity were also affected by DMSO. Therefore, DMSO at 15% and 20% affects sleep architecture in rats, increasing light SWS and reducing deep SWS. Being aware of DMSO behavioural effects seems important since experimental artefacts caused by DMSO can lead to the erroneous interpretation of results.

Hypothalamic L-Histidine Decarboxylase Is Up-Regulated During Chronic REM Sleep Deprivation of Rats.

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Gloria E Hoffman

Full Text Available A competition of neurobehavioral drives of sleep and wakefulness occurs during sleep deprivation. When enforced chronically, subjects must remain awake. This study examines histaminergic neurons of the tuberomammillary nucleus of the posterior hypothalamus in response to enforced wakefulness in rats. We tested the hypothesis that the rate-limiting enzyme for histamine biosynthesis, L-histidine decarboxylase (HDC, would be up-regulated during chronic rapid eye movement sleep deprivation (REM-SD because histamine plays a major role in maintaining wakefulness. Archived brain tissues of male Sprague Dawley rats from a previous study were used. Rats had been subjected to REM-SD by the flowerpot paradigm for 5, 10, or 15 days. For immunocytochemistry, rats were transcardially perfused with acrolein-paraformaldehyde for immunodetection of L-HDC; separate controls used carbodiimide-paraformaldehyde for immunodetection of histamine. Immunolocalization of histamine within the tuberomammillary nucleus was validated using carbodiimide. Because HDC antiserum has cross-reactivity with other decarboxylases at high antibody concentrations, titrations localized L-HDC to only tuberomammillary nucleus at a dilution of ≥ 1:300,000. REM-SD increased immunoreactive HDC by day 5 and it remained elevated in both dorsal and ventral aspects of the tuberomammillary complex. Our results suggest that up-regulation of L-HDC within the tuberomammillary complex during chronic REM-SD may be responsible for maintaining wakefulness.

Local Use-Dependent Sleep in Wakefulness Links Performance Errors to Learning.

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Quercia, Angelica; Zappasodi, Filippo; Committeri, Giorgia; Ferrara, Michele

2018-01-01

Sleep and wakefulness are no longer to be considered as discrete states. During wakefulness brain regions can enter a sleep-like state (off-periods) in response to a prolonged period of activity (local use-dependent sleep). Similarly, during nonREM sleep the slow-wave activity, the hallmark of sleep plasticity, increases locally in brain regions previously involved in a learning task. Recent studies have demonstrated that behavioral performance may be impaired by off-periods in wake in task-related regions. However, the relation between off-periods in wake, related performance errors and learning is still untested in humans. Here, by employing high density electroencephalographic (hd-EEG) recordings, we investigated local use-dependent sleep in wake, asking participants to repeat continuously two intensive spatial navigation tasks. Critically, one task relied on previous map learning (Wayfinding) while the other did not (Control). Behaviorally awake participants, who were not sleep deprived, showed progressive increments of delta activity only during the learning-based spatial navigation task. As shown by source localization, delta activity was mainly localized in the left parietal and bilateral frontal cortices, all regions known to be engaged in spatial navigation tasks. Moreover, during the Wayfinding task, these increments of delta power were specifically associated with errors, whose probability of occurrence was significantly higher compared to the Control task. Unlike the Wayfinding task, during the Control task neither delta activity nor the number of errors increased progressively. Furthermore, during the Wayfinding task, both the number and the amplitude of individual delta waves, as indexes of neuronal silence in wake (off-periods), were significantly higher during errors than hits. Finally, a path analysis linked the use of the spatial navigation circuits undergone to learning plasticity to off periods in wake. In conclusion, local sleep regulation in

Sleep-wake profiles predict longitudinal changes in manic symptoms and memory in young people with mood disorders.

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Robillard, Rébecca; Hermens, Daniel F; Lee, Rico S C; Jones, Andrew; Carpenter, Joanne S; White, Django; Naismith, Sharon L; Southan, James; Whitwell, Bradley; Scott, Elizabeth M; Hickie, Ian B

2016-10-01

Mood disorders are characterized by disabling symptoms and cognitive difficulties which may vary in intensity throughout the course of the illness. Sleep-wake cycles and circadian rhythms influence emotional regulation and cognitive functions. However, the relationships between the sleep-wake disturbances experienced commonly by people with mood disorders and the longitudinal changes in their clinical and cognitive profile are not well characterized. This study investigated associations between initial sleep-wake patterns and longitudinal changes in mood symptoms and cognitive functions in 50 young people (aged 13-33 years) with depression or bipolar disorder. Data were based on actigraphy monitoring conducted over approximately 2 weeks and clinical and neuropsychological assessment. As part of a longitudinal cohort study, these assessments were repeated after a mean follow-up interval of 18.9 months. No significant differences in longitudinal clinical changes were found between the participants with depression and those with bipolar disorder. Lower sleep efficiency was predictive of longitudinal worsening in manic symptoms (P = 0.007). Shorter total sleep time (P = 0.043) and poorer circadian rhythmicity (P = 0.045) were predictive of worsening in verbal memory. These findings suggest that some sleep-wake and circadian disturbances in young people with mood disorders may be associated with less favourable longitudinal outcomes, notably for subsequent manic symptoms and memory difficulties. © 2016 European Sleep Research Society.

Brain mechanisms that control sleep and waking

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Siegel, Jerome

This review paper presents a brief historical survey of the technological and early research that laid the groundwork for recent advances in sleep-waking research. A major advance in this field occurred shortly after the end of World War II with the discovery of the ascending reticular activating system (ARAS) as the neural source in the brain stem of the waking state. Subsequent research showed that the brain stem activating system produced cortical arousal via two pathways: a dorsal route through the thalamus and a ventral route through the hypothalamus and basal forebrain. The nuclei, pathways, and neurotransmitters that comprise the multiple components of these arousal systems are described. Sleep is now recognized as being composed of two very different states: rapid eye movements (REMs) sleep and non-REM sleep. The major findings on the neural mechanisms that control these two sleep states are presented. This review ends with a discussion of two current views on the function of sleep: to maintain the integrity of the immune system and to enhance memory consolidation.

Sleep in prenatally restraint stressed rats, a model of mixed anxiety-depressive disorder.

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Mairesse, Jérôme; Van Camp, Gilles; Gatta, Eleonora; Marrocco, Jordan; Reynaert, Marie-Line; Consolazione, Michol; Morley-Fletcher, Sara; Nicoletti, Ferdinando; Maccari, Stefania

2015-01-01

Prenatal restraint stress (PRS) can induce persisting changes in individual's development. PRS increases anxiety and depression-like behaviors and induces changes in the hypothalamo-pituitary-adrenal (HPA) axis in adult PRS rats after exposure to stress. Since adaptive capabilities also depend on temporal organization and synchronization with the external environment, we studied the effects of PRS on circadian rhythms, including the sleep-wake cycle, that are parameters altered in depression. Using a restraint stress during gestation, we showed that PRS induced phase advances in hormonal/behavioral circadian rhythms in adult rats, and an increase in the amount of paradoxical sleep, positively correlated to plasma corticosterone levels. Plasma corticosterone levels were also correlated with immobility in the forced swimming test, indicating a depressive-like profile in the PRS rats. We observed comorbidity with anxiety-like profile on PRS rats that was correlated with a reduced release of glutamate in the ventral hippocampus. Pharmacological approaches aimed at modulating glutamate release may represent a novel therapeutic strategy to treat stress-related disorders. Finally, since depressed patients exhibit changes in HPA axis activity and in circadian rhythmicity as well as in the paradoxical sleep regulation, we suggest that PRS could represent an original animal model of depression.

Variations in the sleep–wake cycle from childhood to adulthood: chronobiological perspectives

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Carpenter JS

2015-07-01

Full Text Available Joanne S Carpenter, Rébecca Robillard, Ian B HickieClinical Research Unit, Brain and Mind Research Institute, University of Sydney, Camperdown, NSW, AustraliaAbstract: Changes in the sleep–wake cycle across development from childhood to adulthood, typically involve a steady shortening of the sleep period and a delay of sleep phase, with a period of more rapid change across adolescence. Accompanying these changes is the maturation of neuroendocrine rhythms such as melatonin, cortisol, and pubertal hormones. These endogenous rhythms are closely associated with behavioral changes in rest and activity rhythms, although environmental factors such as light exposure and academic and social demands likely play an interactive role. Other behavioral aspects, such as physical activity and eating behaviors, are also associated with changes in sleep–wake rhythms, and may be mediational factors in the development of physical illnesses. The sleep–wake cycle and related factors are implicated in the development of mental illnesses. There are several potential avenues of future research that may be valuable in terms of improving interventions and treatments for both mental and physical illnesses.Keywords: circadian rhythm, developmental, adolescence, youth

Consolidating the effects of waking and sleep on motor-sequence learning.

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Brawn, Timothy P; Fenn, Kimberly M; Nusbaum, Howard C; Margoliash, Daniel

2010-10-20

Sleep is widely believed to play a critical role in memory consolidation. Sleep-dependent consolidation has been studied extensively in humans using an explicit motor-sequence learning paradigm. In this task, performance has been reported to remain stable across wakefulness and improve significantly after sleep, making motor-sequence learning the definitive example of sleep-dependent enhancement. Recent work, however, has shown that enhancement disappears when the task is modified to reduce task-related inhibition that develops over a training session, thus questioning whether sleep actively consolidates motor learning. Here we use the same motor-sequence task to demonstrate sleep-dependent consolidation for motor-sequence learning and explain the discrepancies in results across studies. We show that when training begins in the morning, motor-sequence performance deteriorates across wakefulness and recovers after sleep, whereas performance remains stable across both sleep and subsequent waking with evening training. This pattern of results challenges an influential model of memory consolidation defined by a time-dependent stabilization phase and a sleep-dependent enhancement phase. Moreover, the present results support a new account of the behavioral effects of waking and sleep on explicit motor-sequence learning that is consistent across a wide range of tasks. These observations indicate that current theories of memory consolidation that have been formulated to explain sleep-dependent performance enhancements are insufficient to explain the range of behavioral changes associated with sleep.

Assessment of the Potential Role of Tryptophan as the Precursor of Serotonin and Melatonin for the Aged Sleep-wake Cycle and Immune Function: Streptopelia Risoria as a Model

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Sergio D. Paredes

2009-01-01

Full Text Available In the present review we summarize the relationship between the amino acid, tryptophan, the neurotransmitter, serotonin, and the indole, melatonin, with the rhythms of sleep/wake and the immune response along with the possible connections between the alterations in these rhythms due to aging and the so-called “serotonin and melatonin deficiency state.” The decrease associated with aging of the brain and circulating levels of serotonin and melatonin seemingly contributes to the alterations of both the sleep/wake cycle and the immune response that typically accompany old age. The supplemental administration of tryptophan, e.g. the inclusion of tryptophan-enriched food in the diet, might help to remediate these age- related alterations due to its capacity of raise the serotonin and melatonin levels in the brain and blood. Herein, we also summarize a set of studies related to the potential role that tryptophan, and its derived product melatonin, may play in the restoration of the aged circadian rhythms of sleep/wake and immune response, taking the ringdove (Streptopelia risoria as a suitable model.

Cerveau isolé and pretrigeminal rats.

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Zernicki, B; Gandolfo, G; Glin, L; Gottesmann, C

1984-01-01

Cortical and hippocampal EEG activity was analysed in 14 cerveau isole and 8 pretrigerninal rats. In the acute stage, waking EEG patterns were absent in the cerveau isole, whereas sleep EEG patterns were absent in the pretrigeminal preparations. However, already on the second day the EEG waking-sleep cycle recovered in the majority of rats. Paradoxically, stimuli directed to the caudal part of preparations evoked stronger cortical and hippocampal EEG arousal than olfactory and visual stimuli. The behavior of the caudal part was observed in 25 preparations. Although in abortive form, the rats did show some locomotor and grooming behavior, and could be fed orally. The peripheral events of paradoxical sleep appeared only on the fourth or fifth day of survival of the cerveau isole rats. It is concluded that the activity of the isolated cerebrum of the rat is similar to that of cat preparations, but that functions of the caudal neuraxis are superior in rats.

Cerveau isolé and pretrigeminal rat preparations.

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Zernicki, B; Gandolfo, G; Glin, L; Gottesmann, C

1985-01-01

Cortical and hippocampal EEG activity was analysed in cerveau isolé and and pretrigeminal rats. In the acute stage, waking EEG patterns were absent in the cerveau isolé, whereas sleep EGG patterns were absent in the preparations. However, already on the second day the EEG waking sleep cycle recovered in the majority of rats. Paradoxically, stimuli directed to the caudal part of the preparations evoked stronger cortical and hippocampal EEG arousal than olfactory and visual stimuli. The rats exhibited some locomotor and grooming behaviour and could be fed orally. It is concluded that the activity of the isolated cerebrum of the rat is similar to that of cat preparations, but that functions of the caudal neuraxis are superior in rats.

Longitudinal study of self-awakening and sleep/wake habits in adolescents

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Ikeda H

2012-09-01

Full Text Available Hiroki Ikeda,1 Mitsuo Hayashi21Department of Adult Mental Health, National Institute of Mental Health, National Center of Neurology and Psychiatry, Tokyo; 2Department of Behavioral Sciences, Graduate School of Integrated Arts and Sciences, Hiroshima University, Hiroshima, JapanAbstract: Self-awakening is the ability to awaken without external assistance at a predetermined time. Cross-sectional studies reported that people who self-awaken have sleep/wake habits different from those of people who use external means to wake from sleep. However, no longitudinal study has examined self-awakening. The present study investigated self-awakening, both habitual and inconsistent, compared to awakening by external means in relation to sleep/wake schedules for five consecutive years in 362 students (starting at mean age 15.1 ± 0.3 years. Students who self-awakened consistently for five consecutive years (5% of all students went to bed earlier than those who inconsistently self-awakened (mixed group, 40% or consistently used forced awakening by external means (56%. Awakening during sleep was more frequent and sleep was lighter in the consistently self-awakened group than in the mixed and consistently forced-awakened groups. However, daytime dozing was less frequent and comfort immediately after awakening was greater for the consistently self-awakened group than for the mixed and consistently forced-awakened groups. These results indicate that the three groups have different sleep/wake habits. Previous studies of self-awakening using cross-sectional survey data may have confounded both consistent and inconsistent self-awakening habits. A longitudinal study is necessary to clarify the relationship between the self-awakening habit and sleep/wake patterns.Keywords: habitual self-awakening, sleep/wake pattern, adolescent

The cumulative cost of additional wakefulness: dose-response effects on neurobehavioral functions and sleep physiology from chronic sleep restriction and total sleep deprivation

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Van Dongen, Hans P A.; Maislin, Greg; Mullington, Janet M.; Dinges, David F.

2003-01-01

OBJECTIVES: To inform the debate over whether human sleep can be chronically reduced without consequences, we conducted a dose-response chronic sleep restriction experiment in which waking neurobehavioral and sleep physiological functions were monitored and compared to those for total sleep deprivation. DESIGN: The chronic sleep restriction experiment involved randomization to one of three sleep doses (4 h, 6 h, or 8 h time in bed per night), which were maintained for 14 consecutive days. The total sleep deprivation experiment involved 3 nights without sleep (0 h time in bed). Each study also involved 3 baseline (pre-deprivation) days and 3 recovery days. SETTING: Both experiments were conducted under standardized laboratory conditions with continuous behavioral, physiological and medical monitoring. PARTICIPANTS: A total of n = 48 healthy adults (ages 21-38) participated in the experiments. INTERVENTIONS: Noctumal sleep periods were restricted to 8 h, 6 h or 4 h per day for 14 days, or to 0 h for 3 days. All other sleep was prohibited. RESULTS: Chronic restriction of sleep periods to 4 h or 6 h per night over 14 consecutive days resulted in significant cumulative, dose-dependent deficits in cognitive performance on all tasks. Subjective sleepiness ratings showed an acute response to sleep restriction but only small further increases on subsequent days, and did not significantly differentiate the 6 h and 4 h conditions. Polysomnographic variables and delta power in the non-REM sleep EEG-a putative marker of sleep homeostasis--displayed an acute response to sleep restriction with negligible further changes across the 14 restricted nights. Comparison of chronic sleep restriction to total sleep deprivation showed that the latter resulted in disproportionately large waking neurobehavioral and sleep delta power responses relative to how much sleep was lost. A statistical model revealed that, regardless of the mode of sleep deprivation, lapses in behavioral alertness

Diagnostic and Treatment Challenges of Sighted Non-24-Hour Sleep-Wake Disorder.

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Malkani, Roneil G; Abbott, Sabra M; Reid, Kathryn J; Zee, Phyllis C

2018-04-15

To report the diagnostic and treatment challenges of sighted non-24-hour sleep-wake disorder (N24SWD). We report a series of seven sighted patients with N24SWD clinically evaluated by history and sleep diaries, and when available wrist actigraphy and salivary melatonin levels, and treated with timed melatonin and bright light therapy. Most patients had a history of a delayed sleep-wake pattern prior to developing N24SWD. The typical sleep-wake pattern of N24SWD was seen in the sleep diaries (and in actigraphy when available) in all patients with a daily delay in midpoint of sleep ranging 0.8 to 1.8 hours. Salivary dim light melatonin onset (DLMO) was evaluated in four patients but was missed in one. The estimated phase angle from DLMO to sleep onset ranged from 5.25 to 9 hours. All six patients who attempted timed melatonin and bright light therapy were able to entrain their sleep-wake schedules. Entrainment occurred at a late circadian phase, possibly related to the late timing of melatonin administration, though the patients often preferred late sleep times. Most did not continue treatment and continued to have a non-24-hour sleep-wake pattern. N24SWD is a chronic debilitating disorder that is often overlooked in sighted people and can be challenging to diagnose and treat. Tools to assess circadian pattern and timing can be effectively applied to aid the diagnosis. The progressive delay of the circadian rhythm poses a challenge for determining the most effective timing for melatonin and bright light therapies. Furthermore, once the circadian sleep-wake rhythm is entrained, long-term effectiveness is limited because of the behavioral and environmental structure that is required to maintain stable entrainment. © 2018 American Academy of Sleep Medicine.

Pharmacological profiling of zebrafish behavior using chemical and genetic classification of sleep-wake modifiers

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Nishimura, Yuhei; Okabe, Shiko; Sasagawa, Shota; Murakami, Soichiro; Ashikawa, Yoshifumi; Yuge, Mizuki; Kawaguchi, Koki; Kawase, Reiko; Tanaka, Toshio

2015-01-01

Sleep-wake states are impaired in various neurological disorders. Impairment of sleep-wake states can be an early condition that exacerbates these disorders. Therefore, treating sleep-wake dysfunction may prevent or slow the development of these diseases. Although many gene products are likely to be involved in the sleep-wake disturbance, hypnotics and psychostimulants clinically used are limited in terms of their mode of action and are not without side effects. Therefore, there is a growing ...

Sleep/Wake Patterns and Parental Perceptions of Sleep in Children Born Preterm.

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Biggs, Sarah N; Meltzer, Lisa J; Tapia, Ignacio E; Traylor, Joel; Nixon, Gillian M; Horne, Rosemary S C; Doyle, Lex W; Asztalos, Elizabeth; Mindell, Jodi A; Marcus, Carole L

2016-05-15

To compare sleep/wake patterns in children born preterm in Australia vs Canada and determine cultural differences in the relationship between parental perception of sleep and actual sleep behaviors. Australian and Canadian children born preterm were recruited from the Caffeine for Apnea of Prematurity trial (n = 188, 5-12 y) and underwent 14 days actigraphy monitoring. Parents completed the National Sleep Foundation 2004 Sleep in America questionnaire. Cross-cultural differences in sleep characteristics assessed by actigraphy and parent-reported questionnaire were examined. Correlational analyses determined the associations between parental perceptions of child sleep need and sleep behavior. Actigraphy showed preterm children obtained, on average, 8 h sleep/night, one hour less than population recommendations for their age. There was no difference in total sleep time (TST) between Australian and Canadian cohorts; however, bed and wake times were earlier in Australian children. Bedtimes and TST varied by 60 minutes from night to night in both cohorts. Parent-reported child TST on the National Sleep Foundation questionnaire was 90 minutes longer than recorded by actigraphy. Both bedtime and TST on weekdays and weekends were related to parental perception of child sleep need in the Australian cohort. Only TST on weekdays was related to parental perception of child sleep need in the Canadian cohort. This study suggests that short sleep duration and irregular sleep schedules are common in children born preterm. Cultural differences in the association between parental perception of child sleep need and actual sleep behaviors provide important targets for future sleep health education. © 2016 American Academy of Sleep Medicine.

Sleep/wake behaviours of elite athletes from individual and team sports.

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Lastella, Michele; Roach, Gregory D; Halson, Shona L; Sargent, Charli

2015-01-01

Sleep is an essential component for athlete recovery due to its physiological and psychological restorative effects, yet few studies have explored the habitual sleep/wake behaviour of elite athletes. The aims of the present study were to investigate the habitual sleep/wake behaviour of elite athletes, and to compare the differences in sleep between athletes from individual and team sports. A total of 124 (104 male, 20 female) elite athletes (mean ± s: age 22.2 ± 3.0 years) from five individual sports and four team sports participated in this study. Participants' sleep/wake behaviour was assessed using self-report sleep diaries and wrist activity monitors for a minimum of seven nights (range 7-28 nights) during a typical training phase. Mixed-effects analyses of variances were conducted to compare the differences in the sleep/wake behaviour of athletes from two sport types (i.e. individual and team). Overall, this sample of athletes went to bed at 22:59 ± 1.3, woke up at 07:15 ± 1.2 and obtained 6.8 ± 1.1 h of sleep per night. Athletes from individual sports went to bed earlier, woke up earlier and obtained less sleep (individual vs team; 6.5 vs 7.0 h) than athletes from team sports. These data indicate that athletes obtain well below the recommended 8 h of sleep per night, with shorter sleep durations existing among athletes from individual sports.

Acute effect of methyl bromide on sleep-wakefulness and its

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Tanaka, S; Arito, H; Abuku, S; Imamiya, S

1986-01-01

In an attempt to clarify the acute effects of methyl bromide on the central nervous system, abnormal electrocorticographic activity and changes in sleep-wakefulness and its circadian rhythms were investigated after a single injection of methyl bromide. The effects of possible hydrolyzed products of methyl bromide, methanol and bromine ions on sleep and its rhythms were also examined. It was found that the hydrolyzed products of methyl bromide, bromine ions and methanol exerted little effect on the amounts of wakefulness (W), non-REM sleep (NREMS) and REM sleep (REMS) at the same molar dose as 45 mg methyl bromide/kg. Thus, it can be concluded that the methyl bromide-induced changes in sleep-wakefulness and its circadian rhythms are due to methyl bromide and not to the hydrolyzed products. It was also found that amounts of W, NREMS and REMS were changed dose-dependently after a single injection of methyl bromide and that methyl bromide significantly disrupted the circadian REMS rhythm. 17 references, 1 figure, 1 table.

Narcolepsy susceptibility gene CCR3 modulates sleep-wake patterns in mice.

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Hiromi Toyoda

Full Text Available Narcolepsy is caused by the loss of hypocretin (Hcrt neurons and is associated with multiple genetic and environmental factors. Although abnormalities in immunity are suggested to be involved in the etiology of narcolepsy, no decisive mechanism has been established. We previously reported chemokine (C-C motif receptor 3 (CCR3 as a novel susceptibility gene for narcolepsy. To understand the role of CCR3 in the development of narcolepsy, we investigated sleep-wake patterns of Ccr3 knockout (KO mice. Ccr3 KO mice exhibited fragmented sleep patterns in the light phase, whereas the overall sleep structure in the dark phase did not differ between Ccr3 KO mice and wild-type (WT littermates. Intraperitoneal injection of lipopolysaccharide (LPS promoted wakefulness and suppressed both REM and NREM sleep in the light phase in both Ccr3 KO and WT mice. Conversely, LPS suppressed wakefulness and promoted NREM sleep in the dark phase in both genotypes. After LPS administration, the proportion of time spent in wakefulness was higher, and the proportion of time spent in NREM sleep was lower in Ccr3 KO compared to WT mice only in the light phase. LPS-induced changes in sleep patterns were larger in Ccr3 KO compared to WT mice. Furthermore, we quantified the number of Hcrt neurons and found that Ccr3 KO mice had fewer Hcrt neurons in the lateral hypothalamus compared to WT mice. We found abnormalities in sleep patterns in the resting phase and in the number of Hcrt neurons in Ccr3 KO mice. These observations suggest a role for CCR3 in sleep-wake regulation in narcolepsy patients.

The Sleep–Wake Cycle in the Nicotinic Alpha-9 Acetylcholine Receptor Subunit Knock-Out Mice

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Natalia Madrid-López

2017-10-01

Full Text Available There is a neural matrix controlling the sleep–wake cycle (SWC embedded within high ranking integrative mechanisms in the central nervous system. Nicotinic alpha-9 acetylcholine receptor subunit (alpha-9 nAChR participate in physiological processes occurring in sensory, endocrine and immune systems. There is a relationship between the SWC architecture, body homeostasis and sensory afferents so that disruption of afferent signaling is expected to affect the temporal organization of sleep and wake states. The analysis of the SWC of 9 nAChR knock-out animals may help to reveal the contribution of alpha-9 nAChR to sleep chronobiological determinants. Here we explore the polysomnogram in chronically implanted alpha-9 nAChR knock-out (KO and wild-type (WT individuals of the hybrid CBA/Sv129 mouse strain. Records were obtained in isolation chambers under a stable 12:12 light:dark cycle (LD. To unmask the 24-h modulation of the SWC a skeleton photoperiod (SP protocol was performed. Under LD the daily quota (in % of wakefulness (W, NREM sleep and REM sleep obtained in KO and WT animals were 45, 48 and 7, and 46, 46 and 8 respectively. Both groups exhibit nocturnal phase preference of W as well as diurnal and unimodal phase preference of NREM and REM sleep. The acrophase mean angles of KO vs. WT genotypes were not different (Zeitgeber Time: 6.5 vs. 14.9 for W, 4.3 vs. 2.8 for NREM sleep and 5.3 vs. 3.4 for REM sleep, respectively. Transference to SP do not affect daily state quotas, phase preferences and acrophases among genotypes. Unmasking phenomena of the SWC such as wake increment during the rest phase under SP was evident only among WT mice suggesting the involvement of retinal structures containing alpha-9 nAChR in masking processes. Furthermore, KO animals exhibit longer NREM and REM sleep episodes that is independent of illumination conditions. Consolidated diurnal NREM sleep contributed to obtain higher values of NREM sleep delta-EEG activity

Mild Traumatic Brain Injury Chronically Impairs Sleep- and Wake-Dependent Emotional Processing.

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Mantua, Janna; Henry, Owen S; Garskovas, Nolan F; Spencer, Rebecca M C

2017-06-01

A single traumatic brain injury (TBI), even when mild (ie, concussion), can cause lasting consequences. Individuals with a history of chronic (>1-year prior) mild TBI have an increased risk of mood disturbances (eg, depression, suicide). This population also has lingering sleep alterations, including poor sleep quality and changes in sleep stage proportions. Given these sleep deficits, we aimed to test whether sleep-dependent emotional memory consolidation is reduced in this population. We utilized a mild TBI group (3.7 ± 2.9 years post injury) and an uninjured (non-TBI) population. Participants viewed negative and neutral images both before and after a 12-hour period containing sleep ("Sleep" group) or an equivalent period of time spent awake ("Wake" group). Participants rated images for valence/arousal at both sessions, and memory recognition was tested at session two. The TBI group had less rapid eye movement (REM), longer REM latency, and more sleep complaints. Sleep-dependent memory consolidation of nonemotional images was present in all participants. However, consolidation of negative images was only present in the non-TBI group. A lack of differentiation between the TBI Sleep and Wake groups was due to poor performance in the sleep group and, unexpectedly, enhanced performance in the wake group. Additionally, although the non-TBI participants habituated to negative images over a waking period, the TBI participants did not. We propose disrupted sleep- and wake-dependent emotional processing contributes to poor emotional outcomes following chronic, mild TBI. This work has broad implications, as roughly one-third of the US population will sustain a mild TBI during their lifetime. © 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-wake habits and circadian preference in Mexican secondary school.

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Arrona-Palacios, Arturo; García, Aída; Valdez, Pablo

2015-10-01

The current study aimed to determine the differences between sleep-wake habits and circadian preference in Mexican adolescents attending classes at a morning shift or an afternoon shift. The sample consisted of 568 students of a secondary school in Reynosa, northeastern Mexico, of whom 280 were boys and 288 were girls (mean age 14.08 ± 0.72 years, age range 13-16 years). In the morning shift, 287 students attend classes on a schedule from 7:30 to 13:00 and the afternoon shift, 281 students, on a schedule from 13:20 to 19:00. Students completed a general information questionnaire, the Sleep Timing Questionnaire and the Spanish version of the Morningness-Eveningness Questionnaire. The adolescents who attended the morning shift had earlier bedtime and waking time, but shorter sleep duration than those who attended the afternoon shift. Those oriented to eveningness had later bedtime, waking time, and a shorter sleep duration than those oriented to morningness. Two interactions were found between school shift and chronotype. First, with regard to waking time during weekdays, students who attended the afternoon shift and were oriented to eveningness woke up later than those who attended the morning shift and were oriented to eveningness; during weekdays, there were no differences between the waking time of morning-type and evening-type students who attended the morning shift. Second, with regard to sleep duration on weekdays, students who attended the morning shift and were oriented to eveningness had the shortest sleep duration. Furthermore, there were no differences between sleep duration on weekdays in evening-type and morning-type students of the afternoon shift. Adolescents who attend classes in the morning shift and are oriented to eveningness are the most sleep deprived. Those who attend the afternoon shift will have optimal sleep duration, regardless of their circadian preference. Copyright © 2015 Elsevier B.V. All rights reserved.

Altered sleep-wake patterns in blindness

DEFF Research Database (Denmark)

Aubin, S.; Gacon, C.; Jennum, P.

2016-01-01

discuss variability in the sleep–wake pattern between blind and normal-sighted individuals. Methods Thirty-day actigraphy recordings were collected from 11 blind individuals without residual light perception and 11 age- and sex-matched normal-sighted controls. From these recordings, we extracted...... the Pittsburgh Sleep Quality Index, and chronotype, using the Morningness-Eveningness Questionnaire. Results Although no group differences were found when averaging over the entire recording period, we found a greater variability throughout the 30-days in both sleep efficiency and timing of the night-time sleep...

Sleep-Wake State Tradeoffs, Impulsivity and Life History Theory

Directory of Open Access Journals (Sweden)

Alissa A. Miller

2012-04-01

Full Text Available Evolutionary ecological theory predicts that sleep-wake state tradeoffs may be related to local environmental conditions and should therefore correlate to alterations in behavioral life history strategies. It was predicted that firefighters who slept more and reported better quality sleep on average would exhibit lower impulsivity inclinations related to slower life history trajectories. UPPS impulsivity scores and self-reported sleep averages were analyzed and indicated a negative association between sleep variables and urgency and a positive association with premeditation. Perseverance, and in some cases premeditation, however, disclosed an unpredicted marginally significant positive association between increased and emergency nighttime waking-related sleep deprivation. Sensation seeking was not associated with sleep variables, but was strongly associated with number of biological children. This research contributes to understanding the implications of human sleep across ecological and behavioral contexts and implies further research is necessary for constructing evolutionarily oriented measures of impulsivity inclination and its meaning in the context of life history strategies.

Sex differences in paradoxical sleep: influences of estrus cycle and ovariectomy.

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Fang, J; Fishbein, W

1996-09-23

Previously, we reported that paradoxical sleep (PS) is sexually dimorphic in mice and rats. Since some early studies indicate that PS is suppressed during proestrus night, it is important to know whether the estrus cycle and accompanying circulating ovarian hormones could explain the sexual dimorphism of PS. To examine this, sleep patterns of male rats were compared with those of normal cycling female rats and ovariectomized females in a 12:12 h light/dark cycle. Slow wave sleep and total sleep time are indistinguishable between the males, cycling females and ovariectomized females. However, normal males display significantly more PS than cycling females during both daytime and nighttime (average of all estrus stages). On the other hand, while ovariectomy has no visible effect on daytime sleep--the sexual dimorphism of PS is unchanged by ovariectomy--during nighttime, ovariectomy produces a selective increase of PS, eliminating the sex difference during the night. In sum, normal cycling females show no change in daytime sleep patterns across the estrus cycle, but have significantly less PS during proestrus nights than during metestrus and diestrus nights. The results indicate that the sex difference in nighttime PS is due to the suppression of PS by ovarian hormones during proestrus and, to a less extent, estrus nights. The sex difference in daytime PS, on the other hand, appears to be independent of circulating ovarian hormones.

Sleep-Wake Actigraphy and Light Exposure During Spaceflight - Short

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Czeisler, Charles A.; Wright, Kenneth P., Jr.; Ronda, Joseph

2009-01-01

Sleep-Wake Actigraphy and Light Exposure During Spaceflight - Short (Sleep-Short) will examine the effects of spaceflight on the sleep of the astronauts during space shuttle missions. Advancing state-of-the-art technology for monitoring, diagnosing and assessing treatment of sleep patterns is vital to treating insomnia on Earth and in space.

Pharmacological profiling of zebrafish behavior using chemical and genetic classification of sleep-wake modifiers.

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Nishimura, Yuhei; Okabe, Shiko; Sasagawa, Shota; Murakami, Soichiro; Ashikawa, Yoshifumi; Yuge, Mizuki; Kawaguchi, Koki; Kawase, Reiko; Tanaka, Toshio

2015-01-01

Sleep-wake states are impaired in various neurological disorders. Impairment of sleep-wake states can be an early condition that exacerbates these disorders. Therefore, treating sleep-wake dysfunction may prevent or slow the development of these diseases. Although many gene products are likely to be involved in the sleep-wake disturbance, hypnotics and psychostimulants clinically used are limited in terms of their mode of action and are not without side effects. Therefore, there is a growing demand for developing new hypnotics and psychostimulants with high efficacy and few side effects. Toward this end, animal models are indispensable for use in genetic and chemical screens to identify sleep-wake modifiers. As a proof-of-concept study, we performed behavioral profiling of zebrafish treated with chemical and genetic sleep-wake modifiers. We were able to demonstrate that behavioral profiling of zebrafish treated with hypnotics or psychostimulants from 9 to 10 days post-fertilization was sufficient to identify drugs with specific modes of action. We were also able to identify behavioral endpoints distinguishing GABA-A modulators and hypocretin (hcrt) receptor antagonists and between sympathomimetic and non-sympathomimetic psychostimulants. This behavioral profiling can serve to identify genes related to sleep-wake disturbance associated with various neuropsychiatric diseases and novel therapeutic compounds for insomnia and excessive daytime sleep with fewer adverse side effects.

The development of sleep-wake rhythms and the search for elemental circuits in the infant brain.

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Blumberg, Mark S; Gall, Andrew J; Todd, William D

2014-06-01

Despite the predominance of sleep in early infancy, developmental science has yet to play a major role in shaping concepts and theories about sleep and its associated ultradian and circadian rhythms. Here we argue that developmental analyses help us to elucidate the relative contributions of the brainstem and forebrain to sleep-wake control and to dissect the neural components of sleep-wake rhythms. Developmental analysis also makes it clear that sleep-wake processes in infants are the foundation for those of adults. For example, the infant brainstem alone contains a fundamental sleep-wake circuit that is sufficient to produce transitions among wakefulness, quiet sleep, and active sleep. In addition, consistent with the requirements of a "flip-flop" model of sleep-wake processes, this brainstem circuit supports rapid transitions between states. Later in development, strengthening bidirectional interactions between the brainstem and forebrain contribute to the consolidation of sleep and wake bouts, the elaboration of sleep homeostatic processes, and the emergence of diurnal or nocturnal circadian rhythms. The developmental perspective promoted here critically constrains theories of sleep-wake control and provides a needed framework for the creation of fully realized computational models. Finally, with a better understanding of how this system is constructed developmentally, we will gain insight into the processes that govern its disintegration due to aging and disease.

Adenosine and sleep

International Nuclear Information System (INIS)

Yanik, G.M. Jr.

1987-01-01

Behavioral and biochemical approaches have been used to determine the relative contribution of endogenous adenosine and adenosine receptors to the sleep-wake cycle in the rat. Adenosine concentrations in specific areas of the rat brain were not affected by 24 hours of total sleep deprivation, or by 24 or 48 hours of REM sleep deprivation. In order to assess the effect of REM sleep deprivation on adenosine A 1 receptors, 3 H-L-PIA binding was measured. The Bmax values for 3 H-L-PIA binding to membrane preparations of the cortices and corpus striata from 48 hour REM sleep-deprived animals were increased 14.8% and 23%, respectively. These increases were not maintained following the cessation of sleep deprivation and recovered within 2 hours. The results of a 96 hour REM deprivation experiment were similar to those of the 48 hour REM sleep deprivation experiment. However, these increases were not evident in similar structures taken from stress control animals, and conclusively demonstrated that the changes in 3 H-L-PIA binding resulted from REM sleep deprivation and not from stress

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

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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.

Memory for semantically related and unrelated declarative information: the benefit of sleep, the cost of wake.

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Jessica D Payne

Full Text Available Numerous studies have examined sleep's influence on a range of hippocampus-dependent declarative memory tasks, from text learning to spatial navigation. In this study, we examined the impact of sleep, wake, and time-of-day influences on the processing of declarative information with strong semantic links (semantically related word pairs and information requiring the formation of novel associations (unrelated word pairs. Participants encoded a set of related or unrelated word pairs at either 9 am or 9 pm, and were then tested after an interval of 30 min, 12 hr, or 24 hr. The time of day at which subjects were trained had no effect on training performance or initial memory of either word pair type. At 12 hr retest, memory overall was superior following a night of sleep compared to a day of wakefulness. However, this performance difference was a result of a pronounced deterioration in memory for unrelated word pairs across wake; there was no sleep-wake difference for related word pairs. At 24 hr retest, with all subjects having received both a full night of sleep and a full day of wakefulness, we found that memory was superior when sleep occurred shortly after learning rather than following a full day of wakefulness. Lastly, we present evidence that the rate of deterioration across wakefulness was significantly diminished when a night of sleep preceded the wake period compared to when no sleep preceded wake, suggesting that sleep served to stabilize the memories against the deleterious effects of subsequent wakefulness. Overall, our results demonstrate that 1 the impact of 12 hr of waking interference on memory retention is strongly determined by word-pair type, 2 sleep is most beneficial to memory 24 hr later if it occurs shortly after learning, and 3 sleep does in fact stabilize declarative memories, diminishing the negative impact of subsequent wakefulness.

The rostromedial tegmental nucleus is essential for non-rapid eye movement sleep.

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Su-Rong Yang

2018-04-01

Full Text Available The rostromedial tegmental nucleus (RMTg, also called the GABAergic tail of the ventral tegmental area, projects to the midbrain dopaminergic system, dorsal raphe nucleus, locus coeruleus, and other regions. Whether the RMTg is involved in sleep-wake regulation is unknown. In the present study, pharmacogenetic activation of rat RMTg neurons promoted non-rapid eye movement (NREM sleep with increased slow-wave activity (SWA. Conversely, rats after neurotoxic lesions of 8 or 16 days showed decreased NREM sleep with reduced SWA at lights on. The reduced SWA persisted at least 25 days after lesions. Similarly, pharmacological and pharmacogenetic inactivation of rat RMTg neurons decreased NREM sleep. Electrophysiological experiments combined with optogenetics showed a direct inhibitory connection between the terminals of RMTg neurons and midbrain dopaminergic neurons. The bidirectional effects of the RMTg on the sleep-wake cycle were mimicked by the modulation of ventral tegmental area (VTA/substantia nigra compacta (SNc dopaminergic neuronal activity using a pharmacogenetic approach. Furthermore, during the 2-hour recovery period following 6-hour sleep deprivation, the amount of NREM sleep in both the lesion and control rats was significantly increased compared with baseline levels; however, only the control rats showed a significant increase in SWA compared with baseline levels. Collectively, our findings reveal an essential role of the RMTg in the promotion of NREM sleep and homeostatic regulation.

[Sleep-wake cycle and memory consolidation].

Science.gov (United States)

Baratti, Carlos M; Boccia, Mariano M; Blake, Mariano G; Acosta, Gabriela B

2007-01-01

Although several hypothesis and theories have been advanced as explanations for the functions of sleep, a unified theory of sleep function remains elusive. Sleep has been implicated in the plastic cerebral changes that underlie learning and memory, in particular those related to memory consolidation of recently acquired new information. Despite steady accumulations of positive findings over the last ten years, the precise role of sleep in memory and brain plasticity is unproven at all. This situation might be solved by more integrated approaches that combine behavioral and neurophysiological measurements in well described in vivo models of neuronal activity and brain plasticity.

Deep sleep after social stress : NREM sleep slow-wave activity is enhanced in both winners and losers of a conflict

NARCIS (Netherlands)

Kamphuis, Jeanine; Lancel, Marike; Koolhaas, Jaap M.; Meerlo, Peter

Sleep is considered to be a recovery process of prior wakefulness. Not only duration of the waking period affects sleep architecture and sleep EEG, the quality of wakefulness is also highly important. Studies in rats have shown that social defeat stress, in which experimental animals are attacked

Sleep-Wake Patterns during the Acute Phase after First-Ever Stroke

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Linda N. Bakken

2011-01-01

Full Text Available This study describes the pattern of day and night sleep and explores relationships between these patterns and sociodemographic and clinical factors as well as sleep environmental context and the patient's subjective sleep quality. Data from 110 patients with first-ever stroke was collected by structured interview surveys, medical record, and objective estimated sleep data from wrist actigraphy. The variability in estimated sleep is large. Half the patients slept either 8 hours per night, and 78% had more than nine awakenings per night. Men slept less than women, and patients sleeping at home had fewer awakenings than those who slept in hospital. It was estimated sleep during daytime in all, except 4, patients. Longer stay in hospital was related to more daytime sleep, and the subjective sleep quality correlated with estimated sleep time, wake time, and wake percentage.

Sleep-waking states and the endogenous opioid system

NARCIS (Netherlands)

O.E. Ukponmwan (Otas)

1986-01-01

textabstractIn the general introductory part of this thesis (Chapters and 2) a review of some pertinent literature related to sleep-waking states and opioid peptides is offered. A global view of the neurochemical mechanisms and theories of functions of sleep, as well as the physiological and

Glutamate microinjection in the medial septum of rats decreases paradoxical sleep and increases slow wave sleep.

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Mukherjee, Didhiti; Kaushik, Mahesh K; Jaryal, Ashok Kumar; Kumar, Velayudhan Mohan; Mallick, Hruda Nanda

2012-05-09

The role of the medial septum in suppressing paradoxical sleep and promoting slow wave sleep was suggested on the basis of neurotoxic lesion studies. However, these conclusions need to be substantiated with further experiments, including chemical stimulation studies. In this report, the medial septum was stimulated in adult male rats by microinjection of L-glutamate. Sleep-wakefulness was electrophysiologically recorded, through chronically implanted electrodes, for 2 h before the injection and 4 h after the injection. There was a decrease in paradoxical sleep during the first hour and an increase in slow wave sleep during the second hour after the injection. The present findings not only supported the lesion studies but also showed that the major role of the medial septum is to suppress paradoxical sleep.

Waking up is the hardest thing I do all day: Sleep inertia and sleep drunkenness.

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Trotti, Lynn M

2017-10-01

The transition from sleep to wake is marked by sleep inertia, a distinct state that is measurably different from wakefulness and manifests as performance impairments and sleepiness. Although the precise substrate of sleep inertia is unknown, electroencephalographic, evoked potential, and neuroimaging studies suggest the persistence of some features of sleep beyond the point of awakening. Forced desynchrony studies have demonstrated that sleep inertia impacts cognition differently than do homeostatic and circadian drives and that sleep inertia is most intense during awakenings from the biological night. Recovery sleep after sleep deprivation also amplifies sleep inertia, although the effects of deep sleep vary based on task and timing. In patients with hypersomnolence disorders, especially but not exclusively idiopathic hypersomnia, a more pronounced period of confusion and sleepiness upon awakening, known as "sleep drunkenness", is common and problematic. Optimal treatment of sleep drunkenness is unknown, although several medications have been used with benefit in small case series. Difficulty with awakening is also commonly endorsed by individuals with mood disorders, disproportionately to the general population. This may represent an important treatment target, but evidence-based treatment guidance is not yet available. Copyright © 2016 Elsevier Ltd. All rights reserved.

Sex differences in the circadian regulation of sleep and waking cognition in humans.

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Santhi, Nayantara; Lazar, Alpar S; McCabe, Patrick J; Lo, June C; Groeger, John A; Dijk, Derk-Jan

2016-05-10

The sleep-wake cycle and circadian rhythmicity both contribute to brain function, but whether this contribution differs between men and women and how it varies across cognitive domains and subjective dimensions has not been established. We examined the circadian and sleep-wake-dependent regulation of cognition in 16 men and 18 women in a forced desynchrony protocol and quantified the separate contributions of circadian phase, prior sleep, and elapsed time awake on cognition and sleep. The largest circadian effects were observed for reported sleepiness, mood, and reported effort; the effects on working memory and temporal processing were smaller. Although these effects were seen in both men and women, there were quantitative differences. The amplitude of the circadian modulation was larger in women in 11 of 39 performance measures so that their performance was more impaired in the early morning hours. Principal components analysis of the performance measures yielded three factors, accuracy, effort, and speed, which reflect core performance characteristics in a range of cognitive tasks and therefore are likely to be important for everyday performance. The largest circadian modulation was observed for effort, whereas accuracy exhibited the largest sex difference in circadian modulation. The sex differences in the circadian modulation of cognition could not be explained by sex differences in the circadian amplitude of plasma melatonin and electroencephalographic slow-wave activity. These data establish the impact of circadian rhythmicity and sex on waking cognition and have implications for understanding the regulation of brain function, cognition, and affect in shift-work, jetlag, and aging.

Dynamic Circadian Modulation in a Biomathematical Model for the Effects of Sleep and Sleep Loss on Waking Neurobehavioral Performance

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McCauley, Peter; Kalachev, Leonid V.; Mollicone, Daniel J.; Banks, Siobhan; Dinges, David F.; Van Dongen, Hans P. A.

2013-01-01

Recent experimental observations and theoretical advances have indicated that the homeostatic equilibrium for sleep/wake regulation—and thereby sensitivity to neurobehavioral impairment from sleep loss—is modulated by prior sleep/wake history. This phenomenon was predicted by a biomathematical model developed to explain changes in neurobehavioral performance across days in laboratory studies of total sleep deprivation and sustained sleep restriction. The present paper focuses on the dynamics of neurobehavioral performance within days in this biomathematical model of fatigue. Without increasing the number of model parameters, the model was updated by incorporating time-dependence in the amplitude of the circadian modulation of performance. The updated model was calibrated using a large dataset from three laboratory experiments on psychomotor vigilance test (PVT) performance, under conditions of sleep loss and circadian misalignment; and validated using another large dataset from three different laboratory experiments. The time-dependence of circadian amplitude resulted in improved goodness-of-fit in night shift schedules, nap sleep scenarios, and recovery from prior sleep loss. The updated model predicts that the homeostatic equilibrium for sleep/wake regulation—and thus sensitivity to sleep loss—depends not only on the duration but also on the circadian timing of prior sleep. This novel theoretical insight has important implications for predicting operator alertness during work schedules involving circadian misalignment such as night shift work. Citation: McCauley P; Kalachev LV; Mollicone DJ; Banks S; Dinges DF; Van Dongen HPA. Dynamic circadian modulation in a biomathematical model for the effects of sleep and sleep loss on waking neurobehavioral performance. SLEEP 2013;36(12):1987-1997. PMID:24293775

Auditory Verbal Experience and Agency in Waking, Sleep Onset, REM, and Non-REM Sleep.

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Speth, Jana; Harley, Trevor A; Speth, Clemens

2017-04-01

We present one of the first quantitative studies on auditory verbal experiences ("hearing voices") and auditory verbal agency (inner speech, and specifically "talking to (imaginary) voices or characters") in healthy participants across states of consciousness. Tools of quantitative linguistic analysis were used to measure participants' implicit knowledge of auditory verbal experiences (VE) and auditory verbal agencies (VA), displayed in mentation reports from four different states. Analysis was conducted on a total of 569 mentation reports from rapid eye movement (REM) sleep, non-REM sleep, sleep onset, and waking. Physiology was controlled with the nightcap sleep-wake mentation monitoring system. Sleep-onset hallucinations, traditionally at the focus of scientific attention on auditory verbal hallucinations, showed the lowest degree of VE and VA, whereas REM sleep showed the highest degrees. Degrees of different linguistic-pragmatic aspects of VE and VA likewise depend on the physiological states. The quantity and pragmatics of VE and VA are a function of the physiologically distinct state of consciousness in which they are conceived. Copyright © 2016 Cognitive Science Society, Inc.

Manipulating the circadian and sleep cycles to protect against metabolic disease

Directory of Open Access Journals (Sweden)

Kazunari eNohara

2015-03-01

Full Text Available Modernization of human society parallels an epidemic of metabolic disorders including obesity. Apart from excess caloric intake, a 24/7 lifestyle poses another important challenge to our metabolic health. Recent research under both laboratory and epidemiological settings has indicated that abnormal temporal organization of sleep and wakeful activities including food intake is a significant risk factor for metabolic disease. The circadian clock system is our intrinsic biological timer that regulates internal rhythms such as the sleep/wake cycle and also responses to external stimuli including light and food. Initially thought to be mainly involved in the timing of sleep, the clock and/or clock genes may also play a role in sleep architecture and homeostasis. Importantly, an extensive body of evidence has firmly established a master regulatory role of the clock in energy balance. Together, a close relationship between well-timed circadian/sleep cycles and metabolic health is emerging. Exploiting this functional connection, an important holistic strategy toward curbing the epidemic of metabolic disorders (e.g. obesity involves corrective measures on the circadian clock and sleep. In addition to behavioral and environmental interventions including meal timing and light control, pharmacological agents targeting sleep and circadian clocks promise convenient and effective applications. Recent studies, for example, have reported small molecules targeting specific clock components and displaying robust beneficial effects on sleep and metabolism. Furthermore, a group of clock-amplitude enhancing small molecules (CEMs identified via high-throughput chemical screens are of particular interest for future in vivo studies of their metabolic and sleep efficacies. Elucidating the functional relationship between clock, sleep and metabolism will also have far-reaching implications for various chronic human diseases and aging.

Manipulating the circadian and sleep cycles to protect against metabolic disease.

Science.gov (United States)

Nohara, Kazunari; Yoo, Seung-Hee; Chen, Zheng Jake

2015-01-01

Modernization of human society parallels an epidemic of metabolic disorders including obesity. Apart from excess caloric intake, a 24/7 lifestyle poses another important challenge to our metabolic health. Recent research under both laboratory and epidemiological settings has indicated that abnormal temporal organization of sleep and wakeful activities including food intake is a significant risk factor for metabolic disease. The circadian clock system is our intrinsic biological timer that regulates internal rhythms such as the sleep/wake cycle and also responses to external stimuli including light and food. Initially thought to be mainly involved in the timing of sleep, the clock, and/or clock genes may also play a role in sleep architecture and homeostasis. Importantly, an extensive body of evidence has firmly established a master regulatory role of the clock in energy balance. Together, a close relationship between well-timed circadian/sleep cycles and metabolic health is emerging. Exploiting this functional connection, an important holistic strategy toward curbing the epidemic of metabolic disorders (e.g., obesity) involves corrective measures on the circadian clock and sleep. In addition to behavioral and environmental interventions including meal timing and light control, pharmacological agents targeting sleep and circadian clocks promise convenient and effective applications. Recent studies, for example, have reported small molecules targeting specific clock components and displaying robust beneficial effects on sleep and metabolism. Furthermore, a group of clock-amplitude-enhancing small molecules (CEMs) identified via high-throughput chemical screens are of particular interest for future in vivo studies of their metabolic and sleep efficacies. Elucidating the functional relationship between clock, sleep, and metabolism will also have far-reaching implications for various chronic human diseases and aging.

Effects of 9-hour time zone changes on fatigue and circadian rhythms of sleep/wake and core temperature

Science.gov (United States)

Gander, P. H.; Myhre, G.; Graeber, R. C.; Andersen, H. T.; Lauber, J. K.

1985-01-01

Physiological and psychological disruptions caused by transmeridian flights may affect the ability of flight crews to meet operational demands. To study these effects, 9 Royal Norwegian Airforces P3-Orion crewmembers flew from Norway to California (-9 hr), and back (+9 hr). Rectal temperature, heart rate and wrist activity were recorded every 2 min, fatigue and mood were rated every 2 hr during the waking day, and logs were kept of sleep times and ratings. Subjects also completed 4 personality inventories. The time-zone shifts produced negative changes in mood which persisted longer after westward flights. Sleep quality (subjective and objective) and duration were slightly disrupted (more after eastward flights). The circadian rhythms of sleep/wake and temperature both completed the 9-hr delay by day 5 in California, although temperature adjusted more slowly. The size of the delay shift was significantly correlated with scores on extraversion and achievement need personality scales. Response to the 9-hr advance were more variable. One subject exhibited a 15-hr delay in his temperature rhythm, and an atypical sleep/nap pattern. On average, the sleep/wake cycle (but not the temperature rhythm), completed the 9-hr advance by the end of the study. Both rhythms adapted more slowly after the eastward flight.

Oscillations, neural computations and learning during wake and sleep.

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Penagos, Hector; Varela, Carmen; Wilson, Matthew A

2017-06-01

Learning and memory theories consider sleep and the reactivation of waking hippocampal neural patterns to be crucial for the long-term consolidation of memories. Here we propose that precisely coordinated representations across brain regions allow the inference and evaluation of causal relationships to train an internal generative model of the world. This training starts during wakefulness and strongly benefits from sleep because its recurring nested oscillations may reflect compositional operations that facilitate a hierarchical processing of information, potentially including behavioral policy evaluations. This suggests that an important function of sleep activity is to provide conditions conducive to general inference, prediction and insight, which contribute to a more robust internal model that underlies generalization and adaptive behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

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...

Urotensin II modulates rapid eye movement sleep through activation of brainstem cholinergic neurons

DEFF Research Database (Denmark)

Huitron-Resendiz, Salvador; Kristensen, Morten Pilgaard; Sánchez-Alavez, Manuel

2005-01-01

administration of UII into the PPT nucleus increases REM sleep without inducing changes in the cortical blood flow. Intracerebroventricular injection of UII enhances both REM sleep and wakefulness and reduces slow-wave sleep 2. Intracerebroventricular, but not local, administration of UII increases cortical...... dorsal tegmental nuclei. This distribution suggests that the UII system is involved in functions regulated by acetylcholine, such as the sleep-wake cycle. Here, we tested the hypothesis that UII influences cholinergic PPT neuron activity and alters rapid eye movement (REM) sleep patterns in rats. Local...... synaptic transmission because it persisted in the presence of TTX and antagonists of ionotropic glutamate, GABA, and glycine receptors. Collectively, these results suggest that UII plays a role in the regulation of REM sleep independently of its cerebrovascular actions by directly activating cholinergic...

Cardiovascular and respiratory changes during slow-wave sleep in rats are associated with electrocorticogram desynchronization

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J.R. Dias-dos-Santos

1997-11-01

Full Text Available In awake rats a single recurrent larger tidal volume (deep breaths occurs at regular intervals, followed by oscillations in arterial pressure and heart rate. In the present study we recorded the changes in blood pressure, heart rate and ventilation during the wakefulness-sleep cycle identified by electrocorticographic records in order to determine whether the deep breaths and cardiovascular oscillations were associated with changes in the electrocorticogram. During several episodes of slow-wave sleep (SWS in 7 rats the deep breaths and oscillations in arterial pressure and heart rate were preceded by SWS desynchronization. The interval between deep breaths during SWS was 71 ± 4 s, the period between initial desynchronization and the generation of deep breaths was 3.98 ± 0.45 s and the duration of SWS desynchronization was 11 ± 0.65 s. Hypotension (-16 ± 1 mmHg and tachycardia (+15 ± 5 bpm were observed during deep breaths in the SWS state. These data indicate that the oscillations in arterial pressure and heart rate during SWS are associated with deep breaths, which in turn are preceded by desynchronization of the electrocorticogram in this state of sleep

NREM sleep hypersomnia and reduced sleep/wake continuity in a neuroendocrine mouse model of anxiety/depression based on chronic corticosterone administration.

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Le Dantec, Y; Hache, G; Guilloux, J P; Guiard, B P; David, D J; Adrien, J; Escourrou, P

2014-08-22

Sleep/wake disorders are frequently associated with anxiety and depression and to elevated levels of cortisol. Even though these alterations are increasingly sought in animal models, no study has investigated the specific effects of chronic corticosterone (CORT) administration on sleep. We characterized sleep/wake disorders in a neuroendocrine mouse model of anxiety/depression, based on chronic CORT administration in the drinking water (35 μg/ml for 4 weeks, "CORT model"). The CORT model was markedly affected during the dark phase by non-rapid eye movement sleep (NREM) increase without consistent alteration of rapid eye movement (REM) sleep. Total sleep duration (SD) and sleep efficiency (SE) increased concomitantly during both the 24h and the dark phase, due to the increase in the number of NREM sleep episodes without a change in their mean duration. Conversely, the total duration of wake decreased due to a decrease in the mean duration of wake episodes despite an increase in their number. These results reflect hypersomnia by intrusion of NREM sleep during the active period as well as a decrease in sleep/wake continuity. In addition, NREM sleep was lighter, with an increased electroencephalogram (EEG) theta activity. With regard to REM sleep, the number and the duration of episodes decreased, specifically during the first part of the light period. REM and NREM sleep changes correlated respectively with the anxiety and the anxiety/depressive-like phenotypes, supporting the notion that studying sleep could be of predictive value for altered emotional behavior. The chronic CORT model in mice that displays hallmark characteristics of anxiety and depression provides an insight into understanding the changes in overall sleep architecture that occur under pathological conditions. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Sleep/Wakefulness Management in Continuous/Sustained Operations

National Research Council Canada - National Science Library

2002-01-01

......There is an antinomy between the physiological requirement and the operational requirement. To be able to continue the mission but also to preserve our security and the security of the crew we need an appropriate sleep-wakefulness management...

Sleep pattern and locomotor activity are impaired by doxorubicin in non-tumor-bearing rats.

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Lira, Fabio Santos; Esteves, Andrea Maculano; Pimentel, Gustavo Duarte; Rosa, José Cesar; Frank, Miriam Kannebley; Mariano, Melise Oliveira; Budni, Josiane; Quevedo, João; Santos, Ronaldo Vagner Dos; de Mello, Marco Túlio

2016-01-01

We sought explore the effects of doxorubicin on sleep patterns and locomotor activity. To investigate these effects, two groups were formed: a control group and a Doxorubicin (DOXO) group. Sixteen rats were randomly assigned to either the control or DOXO groups. The sleep patterns were examined by polysomnographic recording and locomotor activity was evaluated in an open-field test. In the light period, the total sleep time and slow wave sleep were decreased, while the wake after sleep onset and arousal were increased in the DOXO group compared with the control group (plocomotor activity.

The sequential hypothesis of sleep function. IV. A correlative analysis of sleep variables in learning and nonlearning rats.

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Langella, M; Colarieti, L; Ambrosini, M V; Giuditta, A

1992-02-01

Female adult rats were trained for a two-way active avoidance task (4 h), and allowed free sleep (3 h). Control rats (C) were left in their home cages during the acquisition period. Dural electrodes and an intraventricular cannula, implanted one week in advance, were used for EEG recording during the period of sleep and for the injection of [3H]thymidine at the beginning of the training session, respectively. Rats were killed at the end of the sleep period, and the DNA-specific activity was determined in the main brain regions and in liver. Correlations among sleep, behavioral and biochemical variables were assessed using Spearman's nonparametric method. In learning rats (L), the number of avoidances was negatively correlated with SS-W variables, and positively correlated with SS-PS variables (episodes of synchronized sleep followed by wakefulness or paradoxical sleep, respectively) and with PS variables. An inverse pattern of correlations was shown by the number of escapes or freezings. No correlations occurred in rats unable to achieve the learning criterion (NL). In L rats, the specific activity of brain DNA was negatively correlated with SS-W variables and positively correlated with SS-PS variables, while essentially no correlation concerned PS variables. On the other hand, in NL rats, comparable correlations were positive with SS-W variables and negative with SS-PS and PS variables. Few and weak correlations occurred in C rats. The data support a role of SS in brain information processing, as postulated by the sequential hypothesis on the function of sleep. In addition, they suggest that the elimination of nonadaptive memory traces may require several SS-W episodes and a terminal SS-PS episode. During PS episodes, adaptive memory traces cleared of nonadaptive components may be copied in more suitable brain sites.

Widespread changes in white matter microstructure after a day of waking and sleep deprivation.

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Torbjørn Elvsåshagen

Full Text Available Elucidating the neurobiological effects of sleep and waking remains an important goal of the neurosciences. Recently, animal studies indicated that sleep is important for cell membrane and myelin maintenance in the brain and that these structures are particularly susceptible to insufficient sleep. Here, we tested the hypothesis that a day of waking and sleep deprivation would be associated with changes in diffusion tensor imaging (DTI indices of white matter microstructure sensitive to axonal membrane and myelin alterations.Twenty-one healthy adult males underwent DTI in the morning [7:30AM; time point (TP1], after 14 hours of waking (TP2, and then after another 9 hours of waking (TP3. Whole brain voxel-wise analysis was performed with tract based spatial statistics.A day of waking was associated with widespread increases in white matter fractional anisotropy, which were mainly driven by radial diffusivity reductions, and sleep deprivation was associated with widespread fractional anisotropy decreases, which were mainly explained by reductions in axial diffusivity. In addition, larger decreases in axial diffusivity after sleep deprivation were associated with greater sleepiness. All DTI changes remained significant after adjusting for hydration measures.This is the first DTI study of sleep deprivation in humans. Although previous studies have observed localized changes in DTI indices of cerebral microstructure over the course of a few hours, further studies are needed to confirm widespread DTI changes within hours of waking and to clarify whether such changes in white matter microstructure serve as neurobiological substrates of sleepiness.

Pharmacological Targeting the REV-ERBs in Sleep/Wake Regulation

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Amador, Ariadna; Huitron-Resendiz, Salvador; Roberts, Amanda J.; Kamenecka, Theodore M.; Solt, Laura A.; Burris, Thomas P.

2016-01-01

The circadian clock maintains appropriate timing for a wide range of behaviors and physiological processes. Circadian behaviors such as sleep and wakefulness are intrinsically dependent on the precise oscillation of the endogenous molecular machinery that regulates the circadian clock. The identical core clock machinery regulates myriad endocrine and metabolic functions providing a link between sleep and metabolic health. The REV-ERBs (REV-ERBα and REV-ERBβ) are nuclear receptors that are key regulators of the molecular clock and have been successfully targeted using small molecule ligands. Recent studies in mice suggest that REV-ERB-specific synthetic agonists modulate metabolic activity as well as alter sleep architecture, inducing wakefulness during the light period. Therefore, these small molecules represent unique tools to extensively study REV-ERB regulation of sleep and wakefulness. In these studies, our aim was to further investigate the therapeutic potential of targeting the REV-ERBs for regulation of sleep by characterizing efficacy, and optimal dosing time of the REV-ERB agonist SR9009 using electroencephalographic (EEG) recordings. Applying different experimental paradigms in mice, our studies establish that SR9009 does not lose efficacy when administered more than once a day, nor does tolerance develop when administered once a day over a three-day dosing regimen. Moreover, through use of a time response paradigm, we determined that although there is an optimal time for administration of SR9009 in terms of maximal efficacy, there is a 12-hour window in which SR9009 elicited a response. Our studies indicate that the REV-ERBs are potential therapeutic targets for treating sleep problems as those encountered as a consequence of shift work or jet lag. PMID:27603791

Sleep fragmentation exacerbates mechanical hypersensitivity and alters subsequent sleep-wake behavior in a mouse model of musculoskeletal sensitization.

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Sutton, Blair C; Opp, Mark R

2014-03-01

Sleep deprivation, or sleep disruption, enhances pain in human subjects. Chronic musculoskeletal pain is prevalent in our society, and constitutes a tremendous public health burden. Although preclinical models of neuropathic and inflammatory pain demonstrate effects on sleep, few studies focus on musculoskeletal pain. We reported elsewhere in this issue of SLEEP that musculoskeletal sensitization alters sleep of mice. In this study we hypothesize that sleep fragmentation during the development of musculoskeletal sensitization will exacerbate subsequent pain responses and alter sleep-wake behavior of mice. This is a preclinical study using C57BL/6J mice to determine the effect on behavioral outcomes of sleep fragmentation combined with musculoskeletal sensitization. Musculoskeletal sensitization, a model of chronic muscle pain, was induced using two unilateral injections of acidified saline (pH 4.0) into the gastrocnemius muscle, spaced 5 days apart. Musculoskeletal sensitization manifests as mechanical hypersensitivity determined by von Frey filament testing at the hindpaws. Sleep fragmentation took place during the consecutive 12-h light periods of the 5 days between intramuscular injections. Electroencephalogram (EEG) and body temperature were recorded from some mice at baseline and for 3 weeks after musculoskeletal sensitization. Mechanical hypersensitivity was determined at preinjection baseline and on days 1, 3, 7, 14, and 21 after sensitization. Two additional experiments were conducted to determine the independent effects of sleep fragmentation or musculoskeletal sensitization on mechanical hypersensitivity. Five days of sleep fragmentation alone did not induce mechanical hypersensitivity, whereas sleep fragmentation combined with musculoskeletal sensitization resulted in prolonged and exacerbated mechanical hypersensitivity. Sleep fragmentation combined with musculoskeletal sensitization had an effect on subsequent sleep of mice as demonstrated by increased

Dynamic circadian modulation in a biomathematical model for the effects of sleep and sleep loss on waking neurobehavioral performance.

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McCauley, Peter; Kalachev, Leonid V; Mollicone, Daniel J; Banks, Siobhan; Dinges, David F; Van Dongen, Hans P A

2013-12-01

Recent experimental observations and theoretical advances have indicated that the homeostatic equilibrium for sleep/wake regulation--and thereby sensitivity to neurobehavioral impairment from sleep loss--is modulated by prior sleep/wake history. This phenomenon was predicted by a biomathematical model developed to explain changes in neurobehavioral performance across days in laboratory studies of total sleep deprivation and sustained sleep restriction. The present paper focuses on the dynamics of neurobehavioral performance within days in this biomathematical model of fatigue. Without increasing the number of model parameters, the model was updated by incorporating time-dependence in the amplitude of the circadian modulation of performance. The updated model was calibrated using a large dataset from three laboratory experiments on psychomotor vigilance test (PVT) performance, under conditions of sleep loss and circadian misalignment; and validated using another large dataset from three different laboratory experiments. The time-dependence of circadian amplitude resulted in improved goodness-of-fit in night shift schedules, nap sleep scenarios, and recovery from prior sleep loss. The updated model predicts that the homeostatic equilibrium for sleep/wake regulation--and thus sensitivity to sleep loss--depends not only on the duration but also on the circadian timing of prior sleep. This novel theoretical insight has important implications for predicting operator alertness during work schedules involving circadian misalignment such as night shift work.

Association between sleep-disordered breathing, sleep-wake pattern, and cognitive impairment among patients with chronic heart failure.

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Hjelm, Carina; Strömberg, Anna; Arestedt, Kristofer; Broström, Anders

2013-05-01

Chronic heart failure (CHF) and sleep-disordered breathing (SDB) are often co-existing problems among the elderly. Apnoeic events may cause cognitive impairment. The aim of the study was to compare sleep and wake patterns, insomnia, daytime sleepiness, and cognitive function in community-dwelling CHF patients, with and without SDB, and to investigate the association between sleep-related factors and cognitive dysfunction. In this cross-sectional observational study, SDB was measured with an ApneaLink device and defined as an apnoea-hypopnoea index (AHI) ≥15/h of sleep. Sleep and wake patterns were measured with actigraphy for 1 week. Insomnia was measured with the Minimal Insomnia Symptom Scale, daytime sleepiness with the Epworth Sleepiness Scale, and cognitive function with a neuropsychological test battery. A total of 137 patients (68% male, median age 72 years, 58% NYHA functional class II) were consecutively included. Forty-four per cent had SDB (AHI ≥15). The SDB group had significantly higher saturation time below 90%, more difficulties maintaining sleep, and lower levels of daytime sleepiness compared with the non-SDB group. Cognitive function and sleep and wake patterns did not differ between the SDB and the non-SDB group. Insomnia was associated with decreased global cognition. The prevalence of cognitive dysfunction was low in this population with predominantly mild to moderate CHF. This might have influenced the lack of associations between cognitive function and SDB. Insomnia was the only sleep-related factor significantly influencing cognition.

Continuous White Noise to Reduce Resistance Going to Sleep and Night Wakings in Toddlers

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Forquer, LeAnne M.; Johnson, C. Merle

2005-01-01

White noise generators were turned on at 75 dB at bedtime and kept on all night to treat resistance going to sleep and night wakings in one-year-old toddlers. In a multiple baseline design four sets of parents recorded duration of resistance going to sleep, number of night wakings, completed surveys of their child's feeding and sleeping patterns…

TMS-induced cortical potentiation during wakefulness locally increases slow wave activity during sleep.

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Reto Huber

2007-03-01

Full Text Available Sleep slow wave activity (SWA is thought to reflect sleep need, increasing in proportion to the length of prior wakefulness and decreasing during sleep. However, the process responsible for SWA regulation is not known. We showed recently that SWA increases locally after a learning task involving a circumscribed brain region, suggesting that SWA may reflect plastic changes triggered by learning.To test this hypothesis directly, we used transcranial magnetic stimulation (TMS in conjunction with high-density EEG in humans. We show that 5-Hz TMS applied to motor cortex induces a localized potentiation of TMS-evoked cortical EEG responses. We then show that, in the sleep episode following 5-Hz TMS, SWA increases markedly (+39.1+/-17.4%, p<0.01, n = 10. Electrode coregistration with magnetic resonance images localized the increase in SWA to the same premotor site as the maximum TMS-induced potentiation during wakefulness. Moreover, the magnitude of potentiation during wakefulness predicts the local increase in SWA during sleep.These results provide direct evidence for a link between plastic changes and the local regulation of sleep need.

Role of basal ganglia in sleep-wake regulation: neural circuitry and clinical significance

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Ramalingam Vetrivelan

2010-11-01

Full Text Available Researchers over the last decade have made substantial progress towards understanding the roles of dopamine and the basal ganglia in the control of sleep-wake behavior. In this review, we outline recent advancements regarding dopaminergic modulation of sleep through the basal ganglia (BG and extra-BG sites. Our main hypothesis is that dopamine promotes sleep by its action on the D2 receptors in the BG and promotes wakefulness by its action on D1 and D2 receptors in the extra-BG sites. This hypothesis implicates dopamine depletion in the BG (such as in Parkinson’s disease in causing frequent nighttime arousal and overall insomnia. Furthermore, the arousal effects of psychostimulants (methamphetamine, cocaine and modafinil may be linked to the ventral periaquductal grey (vPAG dopaminergic circuitry targeting the extra-BG sleep-wake network.

Changes in the sleep-wake rhythm, sleep quality, mood, and quality of life of patients receiving treatment for lung cancer: A longitudinal study.

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Chang, Wen-Pei; Lin, Chia-Chin

2017-01-01

Studies on the diurnal sleep-wake rhythm of patients with lung cancer have mostly examined patients cross-sectionally, whereas the effects of lung cancer treatment over time have rarely been considered. Through long-term longitudinal tracking of patients with lung cancer, this study examined changes in their sleep-wake rhythm, sleep quality, anxiety, depressive symptoms, fatigue and quality of life (QoL) at various treatment stages. In addition, factors affecting their QoL were explored. Hierarchical linear modeling was adopted to analyze a convenience sample of 82 patients with lung cancer. The changes in their sleep-wake rhythm, sleep, mood (anxiety, depressive symptoms and fatigue) and QoL were observed at five time points: prior to treatment and at weeks 6, 12, 24 and 48 after the start of the treatment. The effects of sex, age, cancer stage, treatment type, comorbidities and time were controlled to determine the predictors of patients' QoL. The results showed that patients' sleep-wake rhythms were poor before treatments. Compared with baseline, the sleep-wake rhythms of the patients significantly improved at week 48, and anxiety significantly improved at weeks 6, 12, 24 and 48. By contrast, their fatigue became exacerbated at weeks 8 and 48. Moreover, QoL improved significantly from week 6 until the end of the treatment period. QoL was negatively affected by poor sleep quality (β = -0.69, p = 0.00) and depressive symptoms (β = -2.59, p patients with lung cancer before, during and after treatment. Health-care professionals may also need to provide such patients with health education regarding sleep hygiene and with emotional support to assist them in maintaining regular sleep-wake rhythms in order to improve their QoL.

Evidence for cortical structural plasticity in humans after a day of waking and sleep deprivation.

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Elvsåshagen, Torbjørn; Zak, Nathalia; Norbom, Linn B; Pedersen, Per Ø; Quraishi, Sophia H; Bjørnerud, Atle; Alnæs, Dag; Doan, Nhat Trung; Malt, Ulrik F; Groote, Inge R; Westlye, Lars T

2017-08-01

Sleep is an evolutionarily conserved process required for human health and functioning. Insufficient sleep causes impairments across cognitive domains, and sleep deprivation can have rapid antidepressive effects in mood disorders. However, the neurobiological effects of waking and sleep are not well understood. Recently, animal studies indicated that waking and sleep are associated with substantial cortical structural plasticity. Here, we hypothesized that structural plasticity can be observed after a day of waking and sleep deprivation in the human cerebral cortex. To test this hypothesis, 61 healthy adult males underwent structural magnetic resonance imaging (MRI) at three time points: in the morning after a regular night's sleep, the evening of the same day, and the next morning, either after total sleep deprivation (N=41) or a night of sleep (N=20). We found significantly increased right prefrontal cortical thickness from morning to evening across all participants. In addition, pairwise comparisons in the deprived group between the two morning scans showed significant thinning of mainly bilateral medial parietal cortices after 23h of sleep deprivation, including the precuneus and posterior cingulate cortex. However, there were no significant group (sleep vs. sleep deprived group) by time interactions and we can therefore not rule out that other mechanisms than sleep deprivation per se underlie the bilateral medial parietal cortical thinning observed in the deprived group. Nonetheless, these cortices are thought to subserve wakefulness, are among the brain regions with highest metabolic rate during wake, and are considered some of the most sensitive cortical regions to a variety of insults. Furthermore, greater thinning within the left medial parietal cluster was associated with increased sleepiness after sleep deprivation. Together, these findings add to a growing body of data showing rapid structural plasticity within the human cerebral cortex detectable with

Hypocretin and GABA interact in the pontine reticular formation to increase wakefulness.

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Brevig, Holly N; Watson, Christopher J; Lydic, Ralph; Baghdoyan, Helen A

2010-10-01

Hypocretin-1/orexin A administered directly into the oral part of rat pontine reticular formation (PnO) causes an increase in wakefulness and extracellular gamma-aminobutyric acid (GABA) levels. The receptors in the PnO that mediate these effects have not been identified. Therefore, this study tested the hypothesis that the increase in wakefulness caused by administration of hypocretin-1 into the PnO occurs via activation of GABAA receptors and hypocretin receptors. Within/between subjects. University of Michigan. Twenty-three adult male Crl:CD*(SD) (Sprague Dawley) rats. Microinjection of hypocretin-1, bicuculline (GABAA receptor antagonist), SB-334867 (hypocretin receptor-1 antagonist), and Ringer solution (vehicle control) into the PnO. Hypocretin-1 caused a significant concentration-dependent increase in wakefulness and decrease in rapid eye movement (REM) sleep and non-REM (NREM) sleep. Coadministration of SB-334867 and hypocretin-1 blocked the hypocretin-1-induced increase in wakefulness and decrease in both the NREM and REM phases of sleep. Coadministration of bicuculline and hypocretin-1 blocked the hypocretin-1-induced increase in wakefulness and decrease in NREM sleep caused by hypocretin-1. The increase in wakefulness caused by administering hypocretin-1 to the PnO is mediated by hypocretin receptors and GABAA receptors in the PnO. These results show for the first time that hypocretinergic and GABAergic transmission in the PnO can interact to promote wakefulness.

Low Activity Microstates During Sleep.

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Miyawaki, Hiroyuki; Billeh, Yazan N; Diba, Kamran

2017-06-01

To better understand the distinct activity patterns of the brain during sleep, we observed and investigated periods of diminished oscillatory and population spiking activity lasting for seconds during non-rapid eye movement (non-REM) sleep, which we call "LOW" activity sleep. We analyzed spiking and local field potential (LFP) activity of hippocampal CA1 region alongside neocortical electroencephalogram (EEG) and electromyogram (EMG) in 19 sessions from four male Long-Evans rats (260-360 g) during natural wake/sleep across the 24-hr cycle as well as data from other brain regions obtained from http://crcns.org.1,2. LOW states lasted longer than OFF/DOWN states and were distinguished by a subset of "LOW-active" cells. LOW activity sleep was preceded and followed by increased sharp-wave ripple activity. We also observed decreased slow-wave activity and sleep spindles in the hippocampal LFP and neocortical EEG upon LOW onset, with a partial rebound immediately after LOW. LOW states demonstrated activity patterns consistent with sleep but frequently transitioned into microarousals and showed EMG and LFP differences from small-amplitude irregular activity during quiet waking. Their likelihood decreased within individual non-REM epochs yet increased over the course of sleep. By analyzing data from the entorhinal cortex of rats,1 as well as the hippocampus, the medial prefrontal cortex, the postsubiculum, and the anterior thalamus of mice,2 obtained from http://crcns.org, we confirmed that LOW states corresponded to markedly diminished activity simultaneously in all of these regions. We propose that LOW states are an important microstate within non-REM sleep that provide respite from high-activity sleep and may serve a restorative function. © Sleep Research Society 2017. Published by Oxford University Press [on behalf of the Sleep Research Society].

High-frequency oscillations in human and monkey neocortex during the wake–sleep cycle

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Le Van Quyen, Michel; Muller, Lyle E.; Telenczuk, Bartosz; Halgren, Eric; Cash, Sydney; Hatsopoulos, Nicholas G.; Dehghani, Nima; Destexhe, Alain

2016-01-01

Beta (β)- and gamma (γ)-oscillations are present in different cortical areas and are thought to be inhibition-driven, but it is not known if these properties also apply to γ-oscillations in humans. Here, we analyze such oscillations in high-density microelectrode array recordings in human and monkey during the wake–sleep cycle. In these recordings, units were classified as excitatory and inhibitory cells. We find that γ-oscillations in human and β-oscillations in monkey are characterized by a strong implication of inhibitory neurons, both in terms of their firing rate and their phasic firing with the oscillation cycle. The β- and γ-waves systematically propagate across the array, with similar velocities, during both wake and sleep. However, only in slow-wave sleep (SWS) β- and γ-oscillations are associated with highly coherent and functional interactions across several millimeters of the neocortex. This interaction is specifically pronounced between inhibitory cells. These results suggest that inhibitory cells are dominantly involved in the genesis of β- and γ-oscillations, as well as in the organization of their large-scale coherence in the awake and sleeping brain. The highest oscillation coherence found during SWS suggests that fast oscillations implement a highly coherent reactivation of wake patterns that may support memory consolidation during SWS. PMID:27482084

Sleep/wake scheduling scheme for minimizing end-to-end delay in multi-hop wireless sensor networks

OpenAIRE

Madani Sajjad; Nazir Babar; Hasbullah Halabi

2011-01-01

Abstract We present a sleep/wake schedule protocol for minimizing end-to-end delay for event driven multi-hop wireless sensor networks. In contrast to generic sleep/wake scheduling schemes, our proposed algorithm performs scheduling that is dependent on traffic loads. Nodes adapt their sleep/wake schedule based on traffic loads in response to three important factors, (a) the distance of the node from the sink node, (b) the importance of the node's location from connectivity's perspective, and...

The validity, reliability, and utility of the iButton® for measurement of body temperature circadian rhythms in sleep/wake research.

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Hasselberg, Michael J; McMahon, James; Parker, Kathy

2013-01-01

Changes in core body temperature due to heat transfer through the skin have a major influence on sleep regulation. Traditional measures of skin temperature are often complicated by extensive wiring and are not practical for use in normal living conditions. This review describes studies examining the reliability, validity and utility of the iButton®, a wireless peripheral thermometry device, in sleep/wake research. A review was conducted of English language literature on the iButton as a measure of circadian body temperature rhythms associated with the sleep/wake cycle. Seven studies of the iButtton as a measure of human body temperature were included. The iButton was found to be a reliable and valid measure of body temperature. Its application to human skin was shown to be comfortable and tolerable with no significant adverse reactions. Distal skin temperatures were negatively correlated with sleep/wake activity, and the temperature gradient between the distal and proximal skin (DPG) was identified as an accurate physiological correlate of sleep propensity. Methodological issues included site of data logger placement, temperature masking factors, and temperature data analysis. The iButton is an inexpensive, wireless data logger that can be used to obtain a valid measurement of human skin temperature. It is a practical alternative to traditional measures of circadian rhythms in sleep/wake research. Further research is needed to determine the utility of the iButton in vulnerable populations, including those with neurodegenerative disorders and memory impairment and pediatric populations. Copyright © 2011 Elsevier B.V. All rights reserved.

The physiological role of orexin/hypocretin neurons in the regulation of sleep/wakefulness and neuroendocrine functions

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Ayumu eInutsuka

2013-03-01

Full Text Available The hypothalamus monitors body homeostasis and regulates various behaviors such as feeding, thermogenesis, and sleeping. Orexins (also known as hypocretins were identified as endogenous ligands for two orphan G-protein-coupled receptors in the lateral hypothalamic area. They were initially recognized as regulators of feeding behavior, but they are mainly regarded as key modulators of the sleep/wakefulness cycle. Orexins activate orexin neurons, monoaminergic and cholinergic neurons in the hypothalamus/brainstem regions, to maintain a long, consolidated awake period. Anatomical studies of neural projections from/to orexin neurons and phenotypic characterization of transgenic mice revealed various roles for orexin neurons in the coordination of emotion, energy homeostasis, reward system, and arousal. For example, orexin neurons are regulated by peripheral metabolic cues, including ghrelin, leptin, and glucose concentration. This suggests that they may provide a link between energy homeostasis and arousal states. A link between the limbic system and orexin neurons might be important for increasing vigilance during emotional stimuli. Orexins are also involved in reward systems and the mechanisms of drug addiction. These findings suggest that orexin neurons sense the outer and inner environment of the body and maintain the proper wakefulness level of animals for survival. This review discusses the mechanism by which orexins maintain sleep/wakefulness states and how this mechanism relates to other systems that regulate emotion, reward, and energy homeostasis.

Deep sleep after social stress: NREM sleep slow-wave activity is enhanced in both winners and losers of a conflict.

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Kamphuis, Jeanine; Lancel, Marike; Koolhaas, Jaap M; Meerlo, Peter

2015-07-01

Sleep is considered to be a recovery process of prior wakefulness. Not only duration of the waking period affects sleep architecture and sleep EEG, the quality of wakefulness is also highly important. Studies in rats have shown that social defeat stress, in which experimental animals are attacked and defeated by a dominant conspecific, is followed by an acute increase in NREM sleep EEG slow wave activity (SWA). However, it is not known whether this effect is specific for the stress of social defeat or a result of the conflict per se. In the present experiment, we examined how sleep is affected in both the winners and losers of a social conflict. Sleep-wake patterns and sleep EEG were recorded in male wild-type Groningen rats that were subjected to 1h of social conflict in the middle of the light phase. All animals were confronted with a conspecific of similar aggression level and the conflict took place in a neutral arena where both individuals had an equal chance to either win or lose the conflict. NREM sleep SWA was significantly increased after the social conflict compared to baseline values and a gentle stimulation control condition. REM sleep was significantly suppressed in the first hours after the conflict. Winners and losers did not differ significantly in NREM sleep time, NREM sleep SWA and REM sleep time immediately after the conflict. Losers tended to have slightly more NREM sleep later in the recovery period. This study shows that in rats a social conflict with an unpredictable outcome has quantitatively and qualitatively largely similar acute effects on subsequent sleep in winners and losers. Copyright © 2015 Elsevier Inc. All rights reserved.

A role for the preoptic sleep-promoting system in absence epilepsy.

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Suntsova, N; Kumar, S; Guzman-Marin, R; Alam, M N; Szymusiak, R; McGinty, D

2009-10-01

Absence epilepsy (AE) in humans and the genetic AE model in WAG/Rij rats are both associated with abnormalities in sleep architecture that suggest insufficiency of the sleep-promoting mechanisms. In this study we compared the functionality of sleep-active neuronal groups within two well-established sleep-promoting sites, the ventrolateral and median preoptic nuclei (VLPO and MnPN, respectively), in WAG/Rij and control rats. Neuronal activity was assessed using c-Fos immunoreactivity and chronic single-unit recording techniques. We found that WAG/Rij rats exhibited a lack of sleep-associated c-Fos activation of GABAergic MnPN and VLPO neurons, a lower percentage of MnPN and VLPO cells increasing discharge during sleep and reduced firing rates of MnPN sleep-active neurons, compared to non-epileptic rats. The role of sleep-promoting mechanisms in pathogenesis of absence seizures was assessed in non-epileptic rats using electrical stimulation and chemical manipulations restricted to the MnPN. We found that fractional activation of the sleep-promoting system in waking was sufficient to elicit absence-like seizures. Given that reciprocally interrelated sleep-promoting and arousal neuronal groups control thalamocortical excitability, we hypothesize that malfunctioning of sleep-promoting system results in impaired ascending control over thalamocortical rhythmogenic mechanisms during wake-sleep transitions thus favoring aberrant thalamocortical oscillations. Our findings suggest a pathological basis for AE-associated sleep abnormalities and a mechanism underlying association of absence seizures with wake-sleep transitions.

Why we forget our dreams: Acetylcholine and norepinephrine in wakefulness and REM sleep.

Science.gov (United States)

Becchetti, Andrea; Amadeo, Alida

2016-01-01

The ascending fibers releasing norepinephrine and acetylcholine are highly active during wakefulness. In contrast, during rapid-eye-movement sleep, the neocortical tone is sustained mainly by acetylcholine. By comparing the different physiological features of the norepinephrine and acetylcholine systems in the light of the GANE (glutamate amplifies noradrenergic effects) model, we suggest how to interpret some functional differences between waking and rapid-eye-movement sleep.

Circadian control of the sleep-wake cycle

NARCIS (Netherlands)

Beersma, Domien G. M.; Gordijn, Marijke C. M.

2007-01-01

It is beyond doubt that the timing of sleep is under control of the circadian pacemaker. Humans are a diurnal species; they sleep mostly at night, and they do so at approximately 24-h intervals. If they do not adhere to this general pattern, for instance when working night shifts or when travelling

Comparative effects of melatonin, zolpidem and diazepam on sleep, body temperature, blood pressure and heart rate measured by radiotelemetry in Wistar rats.

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Mailliet, F; Galloux, P; Poisson, D

2001-08-01

The role of melatonin (MLT) in mediating the sleep-wake cycle has been previously suspected of indicating that this substance could be a candidate for a new generation of hypnotics. We investigated whether MLT acted as a sleep promoter or a modulator of sleep temporal timing related to cardiovascular and body temperature (Tb) adaptations to sleep induction. The pharmacological effects of MLT on sleep were compared with zolpidem (ZP) and diazepam (DZ). The radiotelemetry system was used to record the electrocorticogram [slow wave sleep (SWS), paradoxical sleep (PS)], Tb, blood pressure and heart rate in six Wistar rats. DZ (3 mg/kg and 6 mg/kg), ZP (1, 3, 5 and 10 mg/kg) and MLT (2.5 and 5 mg/kg) were delivered intraperitoneally during light (L) and dark (D) periods. MLT increased the number of sleep cycles (L: 30%, D: 110%) and total duration (P<0.05) of PS (L: 70%, D: 150%). In return, ZP (10 mg/kg) presented no effect during L but increased total (40%) and mean duration (37%) of SWS during the D period. DZ modified mean duration of SWS (L: -27%, D: +26%) and increased total duration of SWS (+47%). ZP and DZ induced a more pronounced decrease in Tb than MLT but only DZ induced tachycardia and hypertension. We showed that MLT could not promote sleep and its cardiovascular adaptations despite hypothermia, but modulated the period of ultradian sleep cycles. DZ and ZP promoted sleep and induced hypothermia during the D period. Only DZ disrupted sleep architecture and induced adverse effects on cardiovascular parameters.

Sleep, Hormones, and Circadian Rhythms throughout the Menstrual Cycle in Healthy Women and Women with Premenstrual Dysphoric Disorder.

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Shechter, Ari; Boivin, Diane B

2010-01-01

A relationship exists between the sleep-wake cycle and hormone secretion, which, in women, is further modulated by the menstrual cycle. This interaction can influence sleep across the menstrual cycle in healthy women and in women with premenstrual dysphoric disorder (PMDD), who experience specific alterations of circadian rhythms during their symptomatic luteal phase along with sleep disturbances during this time. This review will address the variation of sleep at different menstrual phases in healthy and PMDD women, as well as changes in circadian rhythms, with an emphasis on their relationship with female sex hormones. It will conclude with a brief discussion on nonpharmacological treatments of PMDD which use chronotherapeutic methods to realign circadian rhythms as a means of improving sleep and mood in these women.

Brain reactivity differentiates subjects with high and low dream recall frequencies during both sleep and wakefulness.

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Eichenlaub, Jean-Baptiste; Bertrand, Olivier; Morlet, Dominique; Ruby, Perrine

2014-05-01

The neurophysiological correlates of dreaming remain unclear. According to the "arousal-retrieval" model, dream encoding depends on intrasleep wakefulness. Consistent with this model, subjects with high and low dream recall frequency (DRF) report differences in intrasleep awakenings. This suggests a possible neurophysiological trait difference between the 2 groups. To test this hypothesis, we compared the brain reactivity (evoked potentials) of subjects with high (HR, N = 18) and low (LR, N = 18) DRF during wakefulness and sleep. During data acquisition, the subjects were presented with sounds to be ignored (first names randomly presented among pure tones) while they were watching a silent movie or sleeping. Brain responses to first names dramatically differed between the 2 groups during both sleep and wakefulness. During wakefulness, the attention-orienting brain response (P3a) and a late parietal response were larger in HR than in LR. During sleep, we also observed between-group differences at the latency of the P3a during N2 and at later latencies during all sleep stages. Our results demonstrate differences in the brain reactivity of HR and LR during both sleep and wakefulness. These results suggest that the ability to recall dreaming is associated with a particular cerebral functional organization, regardless of the state of vigilance.

Influence of chronotype and social zeitgebers on sleep/wake patterns

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A.L. Korczak

2008-10-01

Full Text Available Inter-individual differences in the phase of the endogenous circadian rhythms have been established. Individuals with early circadian phase are called morning types; those with late circadian phase are evening types. The Horne and Östberg Morningness-Eveningness Questionnaire (MEQ is the most frequently used to assess individual chronotype. The distribution of MEQ scores is likely to be biased by several fact, ors, such as gender, age, genetic background, latitude, and social habits. The objective of the present study was to determine the effect of different social synchronizers on the sleep/wake cycle of persons with different chronotypes. Volunteers were selected from a total of 1232 UFPR undergraduate students who completed the MEQ. Thirty-two subjects completed the study, including 8 morning types, 8 evening types and 16 intermediate types. Sleep schedules were recorded by actigraphy for 1 week on two occasions: during the school term and during vacation. Sleep onset and offset times, sleep duration, and mid-sleep time for each chronotype group were compared by the Mann-Whitney U-test separately for school term and vacation. School term and vacation data were compared by the Wilcoxon matched-pair test. Morning types showed earlier sleep times and longer sleep duration compared with evening types (23:00 ± 44 and 508.9 ± 50.27 vs 01:08 ± 61.95 and 456.44 ± 59.08, for the weekdays during vacation. During vacation, the subjects showed later sleep times, except for the morning types, who did not exhibit differences for sleep onset times. The results support the idea that social schedules have an impact on the expression of circadian rhythmicity but this impact depends on the individual chronotype.

Circadian polymorphisms in night owls, in bipolars, and in non-24-hour sleep cycles.

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Kripke, Daniel F; Klimecki, Walter T; Nievergelt, Caroline M; Rex, Katharine M; Murray, Sarah S; Shekhtman, Tatyana; Tranah, Gregory J; Loving, Richard T; Lee, Heon-Jeong; Rhee, Min Kyu; Shadan, Farhad F; Poceta, J Steven; Jamil, Shazia M; Kline, Lawrence E; Kelsoe, John R

2014-10-01

People called night owls habitually have late bedtimes and late times of arising, sometimes suffering a heritable circadian disturbance called delayed sleep phase syndrome (DSPS). Those with DSPS, those with more severe progressively-late non-24-hour sleep-wake cycles, and those with bipolar disorder may share genetic tendencies for slowed or delayed circadian cycles. We searched for polymorphisms associated with DSPS in a case-control study of DSPS research participants and a separate study of Sleep Center patients undergoing polysomnography. In 45 participants, we resequenced portions of 15 circadian genes to identify unknown polymorphisms that might be associated with DSPS, non-24-hour rhythms, or bipolar comorbidities. We then genotyped single nucleotide polymorphisms (SNPs) in both larger samples, using Illumina Golden Gate assays. Associations of SNPs with the DSPS phenotype and with the morningness-eveningness parametric phenotype were computed for both samples, then combined for meta-analyses. Delayed sleep and "eveningness" were inversely associated with loci in circadian genes NFIL3 (rs2482705) and RORC (rs3828057). A group of haplotypes overlapping BHLHE40 was associated with non-24-hour sleep-wake cycles, and less robustly, with delayed sleep and bipolar disorder (e.g., rs34883305, rs34870629, rs74439275, and rs3750275 were associated with n=37, p=4.58E-09, Bonferroni p=2.95E-06). Bright light and melatonin can palliate circadian disorders, and genetics may clarify the underlying circadian photoperiodic mechanisms. After further replication and identification of the causal polymorphisms, these findings may point to future treatments for DSPS, non-24-hour rhythms, and possibly bipolar disorder or depression.

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.

Progressive dopamine and hypocretin deficiencies in Parkinson's disease: is there an impact on sleep and wakefulness?

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Wienecke, Miriam; Werth, Esther; Poryazova, Rositsa; Baumann-Vogel, Heide; Bassetti, Claudio L; Weller, Michael; Waldvogel, Daniel; Storch, Alexander; Baumann, Christian R

2012-12-01

Sleep-wake disturbances are frequent in patients with Parkinson's disease, but prospective controlled electrophysiological studies of sleep in those patients are surprisingly sparse, and the pathophysiology of sleep-wake disturbances in Parkinson's disease remains largely elusive. In particular, the impact of impaired dopaminergic and hypocretin (orexin) signalling on sleep and wakefulness in Parkinson's disease is still unknown. We performed a prospective, controlled electrophysiological study in patients with early and advanced Parkinson's disease, e.g. in subjects with presumably different levels of dopamine and hypocretin cell loss. We compared sleep laboratory tests and cerebrospinal fluid levels with hypocretin-deficient patients with narcolepsy with cataplexy, and with matched controls. Nocturnal sleep efficiency was most decreased in advanced Parkinson patients, and still lower in early Parkinson patients than in narcolepsy subjects. Excessive daytime sleepiness was most severe in narcolepsy patients. In Parkinson patients, objective sleepiness correlated with decrease of cerebrospinal fluid hypocretin levels, and repeated hypocretin measurements in two Parkinson patients revealed a decrease of levels over years. This suggests that dopamine and hypocretin deficiency differentially affect sleep and wakefulness in Parkinson's disease. Poorer sleep quality is linked to dopamine deficiency and other disease-related factors. Despite hypocretin cell loss in Parkinson's disease being only partial, disturbed hypocretin signalling is likely to contribute to excessive daytime sleepiness in Parkinson patients. © 2012 European Sleep Research Society.

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.

Switch-task performance in rats is disturbed by 12 h of sleep deprivation but not by 12 h of sleep fragmentation.

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Leenaars, Cathalijn H C; Joosten, Ruud N J M A; Zwart, Allard; Sandberg, Hans; Ruimschotel, Emma; Hanegraaf, Maaike A J; Dematteis, Maurice; Feenstra, Matthijs G P; van Someren, Eus J W

2012-02-01

Task-switching is an executive function involving the prefrontal cortex. Switching temporarily attenuates the speed and/or accuracy of performance, phenomena referred to as switch costs. In accordance with the idea that prefrontal function is particularly sensitive to sleep loss, switch-costs increase during prolonged waking in humans. It has been difficult to investigate the underlying neurobiological mechanisms because of the lack of a suitable animal model. Here, we introduce the first switch-task for rats and report the effects of sleep deprivation and inactivation of the medial prefrontal cortex. Rats were trained to repeatedly switch between 2 stimulus-response associations, indicated by the presentation of a visual or an auditory stimulus. These stimulus-response associations were offered in blocks, and performance was compared for the first and fifth trials of each block. Performance was tested after exposure to 12 h of total sleep deprivation, sleep fragmentation, and their respective movement control conditions. Finally, it was tested after pharmacological inactivation of the medial prefrontal cortex. Controlled laboratory settings. 15 male Wistar rats. Both accuracy and latency showed switch-costs at baseline. Twelve hours of total sleep deprivation, but not sleep fragmentation, impaired accuracy selectively on the switch-trials. Inactivation of the medial prefrontal cortex by local neuronal inactivation resulted in an overall decrease in accuracy. We developed and validated a switch-task that is sensitive to sleep deprivation. This introduces the possibility for in-depth investigations on the neurobiological mechanisms underlying executive impairments after sleep disturbance in a rat model.

Crossing the invisible line: De-differentiation of wake, sleep and dreaming may engender both creative insight and psychopathology.

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Llewellyn, Sue

2016-11-01

Writing about dreaming, the poet Raymond Carver said "I feel as if I've crossed some kind of invisible line". In creative people, the "line" between wake, dreaming and psychopathology may be porous, engendering a de-differentiated, super-critical, hybrid state. Evidence exists for a relationship between creativity and psychopathology but its nature has been elusive. De-differentiation between wake, sleep and dreaming may be the common substrate, as dream-like cognition pervades wake and wake-like neurophysiology suffuses sleep. Chaos theory posits brain states as inherently labile, transient and dynamically unstable. Over and above transient dissociations, an enduring and, sometimes, progressive, de-differentiation may be possible. Evidence indicates that sleep and dreaming facilitate creative insight. In consequence, a mild to moderate form of de-differentiation may enhance creativity but if wake-like neurobiology permeates sleep this may disrupt sleep-dependent memory processing and emotional regulation. If de-differentiation is progressive and enduring, various forms of psychopathology may result. Copyright © 2016 Elsevier Inc. All rights reserved.

Estimating dim light melatonin onset (DLMO) phase in adolescents using summer or school-year sleep/wake schedules.

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Crowley, Stephanie J; Acebo, Christine; Fallone, Gahan; Carskadon, Mary A

2006-12-01

This analysis examined associations between the salivary dim light melatonin onset (DLMO) phase and self-selected sleep/ wake schedules in groups of children and adolescents during summer vacation and during the school year to determine the degree to which sleep/wake patterns can estimate salivary DLMO phase. Participants slept at home on self-selected schedules for 5 consecutive nights and reported their bedtime and wake-up time via daily telephone messages. Salivary melatonin was sampled in the laboratory on one evening every 30 minutes in dim light (females) contributed 149 DLMO phase and sleep/wake pattern measures while on a school year schedule ("school group"). A separate group, ages 9 to 16 years (mean age = 13.1, SD = 1.3 years, 30 males, 29 females) contributed 59 DLMO phase and sleep/wake pattern measures while on a summer schedule ("summer group"). Bedtime, midsleep time, and wake-up time were positively correlated with DLMO phase in both groups. Although all correlation coefficients for the summer group were statistically greater compared to the school group, the regression equations predicted DLMO phase within +/- 1 hour of the measured DLMO phase in approximately 80% for both groups. DLMO phase can be estimated using self-selected sleep/wake patterns during the school year or summer vacation in healthy children and adolescents.

High-density EEG characterization of brain responses to auditory rhythmic stimuli during wakefulness and NREM sleep.

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Lustenberger, Caroline; Patel, Yogi A; Alagapan, Sankaraleengam; Page, Jessica M; Price, Betsy; Boyle, Michael R; Fröhlich, Flavio

2018-04-01

Auditory rhythmic sensory stimulation modulates brain oscillations by increasing phase-locking to the temporal structure of the stimuli and by increasing the power of specific frequency bands, resulting in Auditory Steady State Responses (ASSR). The ASSR is altered in different diseases of the central nervous system such as schizophrenia. However, in order to use the ASSR as biological markers for disease states, it needs to be understood how different vigilance states and underlying brain activity affect the ASSR. Here, we compared the effects of auditory rhythmic stimuli on EEG brain activity during wake and NREM sleep, investigated the influence of the presence of dominant sleep rhythms on the ASSR, and delineated the topographical distribution of these modulations. Participants (14 healthy males, 20-33 years) completed on the same day a 60 min nap session and two 30 min wakefulness sessions (before and after the nap). During these sessions, amplitude modulated (AM) white noise auditory stimuli at different frequencies were applied. High-density EEG was continuously recorded and time-frequency analyses were performed to assess ASSR during wakefulness and NREM periods. Our analysis revealed that depending on the electrode location, stimulation frequency applied and window/frequencies analysed the ASSR was significantly modulated by sleep pressure (before and after sleep), vigilance state (wake vs. NREM sleep), and the presence of slow wave activity and sleep spindles. Furthermore, AM stimuli increased spindle activity during NREM sleep but not during wakefulness. Thus, (1) electrode location, sleep history, vigilance state and ongoing brain activity needs to be carefully considered when investigating ASSR and (2) auditory rhythmic stimuli during sleep might represent a powerful tool to boost sleep spindles. Copyright © 2017 Elsevier Inc. All rights reserved.

Astronauts Need Their Rest Too: Sleep-Wake Actigraphy and Light Exposure During Space Flight

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Czeisler, Charles; Bloomberg, Jacob; Lee, Angie (Technical Monitor)

2002-01-01

The success and effectiveness of human space flight depends on astronauts' ability to maintain a high level of cognitive performance and vigilance. This alert state ensures the proper operation of sophisticated instrumentation. An important way for humans to remedy fatigue and maintain alertness is to get plenty of rest. Astronauts, however, commonly experience difficulty sleeping while in space. During flight, they may also experience disruption of the body's circadian rhythm - the natural phases the body goes through every day as we oscillate between states of high activity during the waking day and recuperation, rest, and repair during nighttime sleep. Both of these factors are associated with impairment of alertness and performance, which could have important consequences during a mission in space. The human body was designed to sleep at night and be alert and active during the day. We receive these cues from the time of day or amount of light, such as the rising or setting of the sun. However, in the environment of the Space Shuttle or the International Space Station where light levels are highly variable, the characteristics of a 24-hour light/dark cycle are not present to cue the astronauts' bodies about what time of the day it is. Astronauts orbiting Earth see a sunset and sunrise every 90 minutes, sending potentially disruptive signals to the area of the brain that regulates sleep. On STS-107, researchers will measure sleep-wake activity with state-of-the-art technology to quantify how much sleep astronauts obtain in space. Because light is the most powerful time cue to the body's circadian system, individual light exposure patterns of the astronauts will also be monitored to determine if light exposure is associated with sleep disruption. The results of this research could lead to the development of a new treatment for sleep disturbances, enabling crewmembers to avoid the decrements in alertness and performance due to sleep deprivation. What we learn

Sleep, Hormones, and Circadian Rhythms throughout the Menstrual Cycle in Healthy Women and Women with Premenstrual Dysphoric Disorder

Directory of Open Access Journals (Sweden)

Ari Shechter

2010-01-01

Full Text Available A relationship exists between the sleep-wake cycle and hormone secretion, which, in women, is further modulated by the menstrual cycle. This interaction can influence sleep across the menstrual cycle in healthy women and in women with premenstrual dysphoric disorder (PMDD, who experience specific alterations of circadian rhythms during their symptomatic luteal phase along with sleep disturbances during this time. This review will address the variation of sleep at different menstrual phases in healthy and PMDD women, as well as changes in circadian rhythms, with an emphasis on their relationship with female sex hormones. It will conclude with a brief discussion on nonpharmacological treatments of PMDD which use chronotherapeutic methods to realign circadian rhythms as a means of improving sleep and mood in these women.

The Hypocretin/Orexin Antagonist Almorexant Promotes Sleep Without Impairment of Performance in Rats

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Stephen R Morairty

2014-01-01

Full Text Available The hypocretin receptor (HcrtR antagonist almorexant (ALM has potent hypnotic actions but little is known about neurocognitive performance in the presence of ALM. HcrtR antagonists are hypothesized to induce sleep by disfacilitation of wake-promoting systems whereas GABAA receptor modulators such as zolpidem (ZOL induce sleep through general inhibition of neural activity. To test the hypothesis that less functional impairment results from HcrtR antagonist-induced sleep, we evaluated the performance of rats in the Morris Water Maze in the presence of ALM vs. ZOL. Performance in spatial reference memory (SRM and spatial working memory (SWM tasks were assessed during the dark period after equipotent sleep-promoting doses (100 mg/kg, po following undisturbed and sleep deprivation (SD conditions. ALM-treated rats were indistinguishable from vehicle (VEH-treated rats for all SRM performance measures (distance travelled, latency to enter, time within, and number of entries into, the target quadrant after both the undisturbed and 6 h SD conditions. In contrast, rats administered ZOL showed impairments in all parameters measured compared to VEH or ALM in the undisturbed conditions. Following SD, ZOL-treated rats also showed impairments in all measures. ALM-treated rats were similar to VEH-treated rats for all SWM measures (velocity, time to locate the platform and success rate at finding the platform within 60 s after both the undisturbed and SD conditions. In contrast, ZOL-treated rats showed impairments in velocity and in the time to locate the platform. Importantly, ZOL rats only completed the task 23-50% of the time while ALM and VEH rats completed the task 79-100% of the time. Thus, following equipotent sleep-promoting doses, ZOL impaired rats in both memory tasks while ALM rats performed at levels comparable to VEH rats. These results are consistent with the hypothesis that less impairment results from HcrtR antagonism than from GABAA

[24-hour work: the interaction of stress and changes in the sleep-wake cycle in the police force].

Science.gov (United States)

Garbarino, Sergio

2014-01-01

Disruption in police officers. In recent years there has been a widespread growth in services, available regardless of time or day organization (24/7 service) and a diffuse increase in their use, both in work and private lives, generally ignoring the importance of a regular sleep organization. Police officers - often need to work extended shifts and long hours under highly stressful conditions, which results in reduced levels of safety and operational effectiveness. In numerous studies, perceived stress has been found to correlate with both subjective and objective disturbances in sleep. Consequently, excessive daytime sleepiness is one of the most frequent health and safety hazards that police officers have to deal with. Sleep deprivation affects performance outcomes through a wide range of cognitive domains. Sleepiness and fatigue, caused by sleep loss, extended work and wakefulness, circadian misalignment and sleep disorders are major causes of workplace human errors, incidents, and accidents. Therefore, prevention of sleep loss, high levels of stress and fatigue is a key factor to consider when assessing emergency intervention. In order to combat fatigue and sleepiness, a 30-90 minutes nap before night shift could be a viable option.

Social Experience Is Sufficient to Modulate Sleep Need of Drosophila without Increasing Wakefulness.

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Lone, Shahnaz Rahman; Potdar, Sheetal; Srivastava, Manishi; Sharma, Vijay Kumar

2016-01-01

Organisms quickly learn about their surroundings and display synaptic plasticity which is thought to be critical for their survival. For example, fruit flies Drosophila melanogaster exposed to highly enriched social environment are found to show increased synaptic connections and a corresponding increase in sleep. Here we asked if social environment comprising a pair of same-sex individuals could enhance sleep in the participating individuals. To study this, we maintained individuals of D. melanogaster in same-sex pairs for a period of 1 to 4 days, and after separation, monitored sleep of the previously socialized and solitary individuals under similar conditions. Males maintained in pairs for 3 or more days were found to sleep significantly more during daytime and showed a tendency to fall asleep sooner as compared to solitary controls (both measures together are henceforth referred to as "sleep-enhancement"). This sleep phenotype is not strain-specific as it is observed in males from three different "wild type" strains of D. melanogaster. Previous studies on social interaction mediated sleep-enhancement presumed 'waking experience' during the interaction to be the primary underlying cause; however, we found sleep-enhancement to occur without any significant increase in wakefulness. Furthermore, while sleep-enhancement due to group-wise social interaction requires Pigment Dispersing Factor (PDF) positive neurons; PDF positive and CRYPTOCHROME (CRY) positive circadian clock neurons and the core circadian clock genes are not required for sleep-enhancement to occur when males interact in pairs. Pair-wise social interaction mediated sleep-enhancement requires dopamine and olfactory signaling, while visual and gustatory signaling systems seem to be dispensable. These results suggest that socialization alone (without any change in wakefulness) is sufficient to cause sleep-enhancement in fruit fly D. melanogaster males, and that its neuronal control is context-specific.

Social Experience Is Sufficient to Modulate Sleep Need of Drosophila without Increasing Wakefulness.

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Shahnaz Rahman Lone

Full Text Available Organisms quickly learn about their surroundings and display synaptic plasticity which is thought to be critical for their survival. For example, fruit flies Drosophila melanogaster exposed to highly enriched social environment are found to show increased synaptic connections and a corresponding increase in sleep. Here we asked if social environment comprising a pair of same-sex individuals could enhance sleep in the participating individuals. To study this, we maintained individuals of D. melanogaster in same-sex pairs for a period of 1 to 4 days, and after separation, monitored sleep of the previously socialized and solitary individuals under similar conditions. Males maintained in pairs for 3 or more days were found to sleep significantly more during daytime and showed a tendency to fall asleep sooner as compared to solitary controls (both measures together are henceforth referred to as "sleep-enhancement". This sleep phenotype is not strain-specific as it is observed in males from three different "wild type" strains of D. melanogaster. Previous studies on social interaction mediated sleep-enhancement presumed 'waking experience' during the interaction to be the primary underlying cause; however, we found sleep-enhancement to occur without any significant increase in wakefulness. Furthermore, while sleep-enhancement due to group-wise social interaction requires Pigment Dispersing Factor (PDF positive neurons; PDF positive and CRYPTOCHROME (CRY positive circadian clock neurons and the core circadian clock genes are not required for sleep-enhancement to occur when males interact in pairs. Pair-wise social interaction mediated sleep-enhancement requires dopamine and olfactory signaling, while visual and gustatory signaling systems seem to be dispensable. These results suggest that socialization alone (without any change in wakefulness is sufficient to cause sleep-enhancement in fruit fly D. melanogaster males, and that its neuronal control is

Pedunculopontine Nucleus Gamma Band Activity-Preconscious Awareness, Waking, and REM Sleep

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Francisco J Urbano

2014-10-01

Full Text Available The pedunculopontine nucleus (PPN is a major component of the reticular activating system (RAS that regulates waking and REM sleep, states of high frequency EEG activity. Recently, we described the presence of high threshold, voltage-dependent N- and P/Q-type calcium channels in RAS nuclei that subserve gamma band oscillations in the mesopontine pedunculopontine nucleus (PPN, intralaminar parafascicular nucleus (Pf, and pontine Subcoeruleus nucleus dorsalis (SubCD. Cortical gamma band activity participates in sensory perception, problem solving, and memory. Rather than participating in the temporal binding of sensory events as in the cortex, gamma band activity in the RAS may participate in the processes of preconscious awareness, and provide the essential stream of information for the formulation of many of our actions. That is, the RAS may play an early permissive role in volition. Our latest results suggest that, 1 the manifestation of gamma band activity during waking may employ a separate intracellular pathway compared to that during REM sleep, 2 neuronal calcium sensor (NCS-1 protein, which is over expressed in schizophrenia and bipolar disorder, modulates gamma band oscillations in the PPN in a concentration-dependent manner, 3 leptin, which undergoes resistance in obesity resulting in sleep dysregulation, decreases sodium currents in PPN neurons, accounting for its normal attenuation of waking, and 4 following our discovery of electrical coupling in the RAS, we hypothesize that there are cell clusters within the PPN that may act in concert. These results provide novel information on the mechanisms controlling high frequency activity related to waking and REM sleep by elements of the RAS.

Neurons Containing Orexin or Melanin Concentrating Hormone Reciprocally Regulate Wake and Sleep

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Roda Rani eKonadhode

2015-01-01

Full Text Available There is considerable amount of data on arousal neurons whereas there is a paucity of knowledge regarding neurons that make us fall asleep. Indeed, current network models of sleep-wake regulation list many arousal neuronal populations compared to only one sleep group located in the preoptic area. There are neurons outside the preoptic area that are active during sleep, but they have never been selectively manipulated. Indeed, none of the sleep-active neurons have been selectively stimulated. To close this knowledge gap we used optogenetics to selectively manipulate neurons containing melanin concentrating hormone (MCH. The MCH neurons are located in the posterior hypothalamus intermingled with the orexin arousal neurons. Our data indicated that optogenetic stimulation of MCH neurons in wildtype mice (J Neuroscience, 2013 robustly increased both non-REM and REM sleep. MCH neuron stimulation increased sleep during the animal’s normal active period, which is compelling evidence that stimulation of MCH neurons has a powerful effect in counteracting the strong arousal signal from all of the arousal neurons. The MCH neurons represent the only group of sleep-active neurons that when selectively stimulated induce sleep. From a translational perspective this is potentially useful in sleep disorders, such as insomnia, where sleep needs to be triggered against a strong arousal drive. Our studies indicate that the MCH neurons belong within an overall model of sleep-wake regulation.

Hypocretin (orexin regulation of sleep-to-wake transitions

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Luis eDe Lecea

2014-02-01

Full Text Available The hypocretin (Hcrt, also known as orexin, peptides are essential for arousal stability. Here I discuss background information about the interaction of Hcrt with other neuromodulators, including norepinephrine and acetylcholine probed with optogenetics. I conclude that Hcrt neurons integrate metabolic, circadian and limbic inputs and convey this information to a network of neuromodulators, each of which has a different role on the dynamic of sleep-to-wake transitions. This model may prove useful to predict the effects of orexin receptor antagonists in sleep disorders and other conditions.

Sleep-Wake Differences in Relative Regional Cerebral Metabolic Rate for Glucose among Patients with Insomnia Compared with Good Sleepers

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Kay, Daniel B.; Karim, Helmet T.; Soehner, Adriane M.; Hasler, Brant P.; Wilckens, Kristine A.; James, Jeffrey A.; Aizenstein, Howard J.; Price, Julie C.; Rosario, Bedda L.; Kupfer, David J.; Germain, Anne; Hall, Martica H.; Franzen, Peter L.; Nofzinger, Eric A.; Buysse, Daniel J.

2016-01-01

Study Objectives: The neurobiological mechanisms of insomnia may involve altered patterns of activation across sleep-wake states in brain regions associated with cognition, self-referential processes, affect, and sleep-wake promotion. The objective of this study was to compare relative regional cerebral metabolic rate for glucose (rCMRglc) in these brain regions across wake and nonrapid eye movement (NREM) sleep states in patients with primary insomnia (PI) and good sleeper controls (GS). Methods: Participants included 44 PI and 40 GS matched for age (mean = 37 y old, range 21–60), sex, and race. We conducted [18F]fluoro-2-deoxy-d-glucose positron emission tomography scans in PI and GS during both morning wakefulness and NREM sleep at night. Repeated measures analysis of variance was used to test for group (PI vs. GS) by state (wake vs. NREM sleep) interactions in relative rCMRglc. Results: Significant group-by-state interactions in relative rCMRglc were found in the precuneus/posterior cingulate cortex, left middle frontal gyrus, left inferior/superior parietal lobules, left lingual/fusiform/occipital gyri, and right lingual gyrus. All clusters were significant at Pcorrected sleep and wakefulness. Significant group-by-state interactions in relative rCMRglc suggest that insomnia is associated with impaired disengagement of brain regions involved in cognition (left frontoparietal), self-referential processes (precuneus/posterior cingulate), and affect (left middle frontal, fusiform/lingual gyri) during NREM sleep, or alternatively, to impaired engagement of these regions during wakefulness. Citation: Kay DB, Karim HT, Soehner AM, Hasler BP, Wilckens KA, James JA, Aizenstein HJ, Price JC, Rosario BL, Kupfer DJ, Germain A, Hall MH, Franzen PL, Nofzinger EA, Buysse DJ. Sleep-wake differences in relative regional cerebral metabolic rate for glucose among patients with insomnia compared with good sleepers. SLEEP 2016;39(10):1779–1794. PMID:27568812

The relationship between shift work and sleep patterns in nurses

OpenAIRE

De Martino,Milva Maria Figueiredo; Abreu,Ana Cristina Basto; Barbosa,Manuel Fernando dos Santos; Teixeira,João Eduardo Marques

2013-01-01

The scope of this study was to evaluate the sleep/wake cycle in shift work nurses, as well as their sleep quality and chronotype. The sleep/wake cycle was evaluated by keeping a sleep diary for a total of 60 nurses with a mean age of 31.76 years. The Horne & Östberg Questionnaire (1976) for the chronotype and the Pittsburgh Sleep Quality Index (PSQI) for sleep quality were applied. The results revealed a predominance of indifferent chronotypes (65.0%), followed by moderately evening perso...

Memory-based detection of rare sound feature combinations in anesthetized rats.

Science.gov (United States)

Astikainen, Piia; Ruusuvirta, Timo; Wikgren, Jan; Penttonen, Markku

2006-10-02

It is unclear whether the ability of the brain to discriminate rare from frequently repeated combinations of sound features is limited to the normal sleep/wake cycle. We recorded epidural auditory event-related potentials in urethane-anesthetized rats presented with rare tones ('deviants') interspersed with frequently repeated ones ('standards'). Deviants differed from standards either in frequency alone or in frequency combined with intensity. In both cases, deviants elicited event-related potentials exceeding in amplitude event-related potentials to standards between 76 and 108 ms from the stimulus onset, suggesting the independence of the underlying integrative and memory-based change detection mechanisms of the brain from the normal sleep/wake cycle. The relations of these event-related potentials to mismatch negativity and N1 in humans are addressed.

Lithium prevents REM sleep deprivation-induced impairments on memory consolidation.

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Ota, Simone M; Moreira, Karin Di Monteiro; Suchecki, Deborah; Oliveira, Maria Gabriela M; Tiba, Paula A

2013-11-01

Pre-training rapid eye movement sleep (REMS) deprivation affects memory acquisition and/or consolidation. It also produces major REMS rebound at the cost of waking and slow wave sleep (SWS). Given that both SWS and REMS appear to be important for memory processes, REMS rebound after training may disrupt the organization of sleep cycles, i.e., excessive amount of REMS and/or little SWS after training could be harmful for memory formation. To examine whether lithium, a drug known to increase SWS and reduce REMS, could prevent the memory impairment induced by pre-training sleep deprivation. Animals were divided in 2 groups: cage control (CC) and REMS-deprived (REMSDep), and then subdivided into 4 subgroups, treated either with vehicle or 1 of 3 doses of lithium (50, 100, and 150 mg/kg) 2 h before training on the multiple trial inhibitory avoidance task. Animals were tested 48 h later to make sure that the drug had been already metabolized and eliminated. Another set of animals was implanted with electrodes and submitted to the same experimental protocol for assessment of drug-induced sleep-wake changes. Wistar male rats weighing 300-400 g. Sleep deprived rats required more trials to learn the task and still showed a performance deficit during test, except from those treated with 150 mg/kg of lithium, which also reduced the time spent in REM sleep during sleep recovery. Lithium reduced rapid eye movement sleep and prevented memory impairment induced by sleep deprivation. These results indicate that these phenomena may be related, but cause-effect relationship cannot be ascertained.

Sex differences in the circadian regulation of sleep and waking cognition in humans

Science.gov (United States)

Santhi, Nayantara; Lazar, Alpar S.; McCabe, Patrick J.; Lo, June C.; Groeger, John A.; Dijk, Derk-Jan

2016-01-01

The sleep–wake cycle and circadian rhythmicity both contribute to brain function, but whether this contribution differs between men and women and how it varies across cognitive domains and subjective dimensions has not been established. We examined the circadian and sleep–wake-dependent regulation of cognition in 16 men and 18 women in a forced desynchrony protocol and quantified the separate contributions of circadian phase, prior sleep, and elapsed time awake on cognition and sleep. The largest circadian effects were observed for reported sleepiness, mood, and reported effort; the effects on working memory and temporal processing were smaller. Although these effects were seen in both men and women, there were quantitative differences. The amplitude of the circadian modulation was larger in women in 11 of 39 performance measures so that their performance was more impaired in the early morning hours. Principal components analysis of the performance measures yielded three factors, accuracy, effort, and speed, which reflect core performance characteristics in a range of cognitive tasks and therefore are likely to be important for everyday performance. The largest circadian modulation was observed for effort, whereas accuracy exhibited the largest sex difference in circadian modulation. The sex differences in the circadian modulation of cognition could not be explained by sex differences in the circadian amplitude of plasma melatonin and electroencephalographic slow-wave activity. These data establish the impact of circadian rhythmicity and sex on waking cognition and have implications for understanding the regulation of brain function, cognition, and affect in shift-work, jetlag, and aging. PMID:27091961

Engineering a thalamo-cortico-thalamic circuit on SpiNNaker: a preliminary study towards modelling sleep and wakefulness

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Basabdatta Sen Bhattacharya

2014-05-01

Full Text Available We present a preliminary study of a thalamo-cortico-thalamic (TCT implementation on SpiNNaker (Spiking Neural Network architecture, a brain inspired hardware platform designed to incorporate the inherent biological properties of parallelism, fault tolerance and energy efficiency. These attributes make SpiNNaker an ideal platform for simulating biologically plausible computational models. Our focus in this work is to design a TCT framework that can be simulated on SpiNNaker to mimic dynamical behaviour similar to Electroencephalogram (EEG time and power-spectra signatures in sleep-wake transition. The scale of the model is minimised for simplicity in this proof-of-concept study; thus the total number of spiking neurons is approximately 1000 and represents a `mini-column' of the thalamocortical tissue. All data on model structure, synaptic layout and parameters is inspired from previous studies and abstracted at a level that is appropriate to the aims of the current study as well as computationally suitable for model simulation on a small 4-chip SpiNNaker system. The initial results from selective deletion of synaptic connectivity parameters in the model show similarity with EEG time series characteristics of sleep and wakefulness. These observations provide a positive perspective and a basis for future implementation of a very large scale biologically plausible model of thalamo-cortico-thalamic interactivity---the essential brain circuit that regulates the biological sleep-wake cycle and associated EEG rhythms.

The Impact of Subthalamic Deep Brain Stimulation on Sleep-Wake Behavior: A Prospective Electrophysiological Study in 50 Parkinson Patients.

Science.gov (United States)

Baumann-Vogel, Heide; Imbach, Lukas L; Sürücü, Oguzkan; Stieglitz, Lennart; Waldvogel, Daniel; Baumann, Christian R; Werth, Esther

2017-05-01

This prospective observational study was designed to systematically examine the effect of subthalamic deep brain stimulation (DBS) on subjective and objective sleep-wake parameters in Parkinson patients. In 50 consecutive Parkinson patients undergoing subthalamic DBS, we assessed motor symptoms, medication, the position of DBS electrodes within the subthalamic nucleus (STN), subjective sleep-wake parameters, 2-week actigraphy, video-polysomnography studies, and sleep electroencepahalogram frequency and dynamics analyses before and 6 months after surgery. Subthalamic DBS improved not only motor symptoms and reduced daily intake of dopaminergic agents but also enhanced subjective sleep quality and reduced sleepiness (Epworth Sleepiness Scale: -2.1 ± 3.8, p sleep efficiency (+5.2 ± 17.6%, p = .005) and deep sleep (+11.2 ± 32.2 min, p = .017) and increased accumulation of slow-wave activity over the night (+41.0 ± 80.0%, p = .005). Rapid eye movement sleep features were refractory to subthalamic DBS, and the dynamics of sleep as assessed by state space analyses did not normalize. Increased sleep efficiency was associated with active electrode contact localization more distant from the ventral margin of the left subthalamic nucleus. Subthalamic DBS deepens and consolidates nocturnal sleep and improves daytime wakefulness in Parkinson patients, but several outcomes suggest that it does not normalize sleep. It remains elusive whether modulated activity in the STN directly contributes to changes in sleep-wake behavior, but dorsal positioning of electrodes within the STN is linked to improved sleep-wake outcomes. © 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.

Investigation of Murine Models for Sleep, Wakefulness and Target Discovery

National Research Council Canada - National Science Library

Ye, Gui-lan; Lanthorn, Thomas; Savelieva, Katerina

2007-01-01

Genetic inhibition of two genes, an orphan GPCR and a kinase, have been shown to produce changes in the behavior of mice that suggest the ability to promote sleep and to promote extended wakefulness...

Increased Sleep Need and Reduction of Tuberomammillary Histamine Neurons after Rodent Traumatic Brain Injury.

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Noain, Daniela; Büchele, Fabian; Schreglmann, Sebastian R; Valko, Philipp O; Gavrilov, Yuri V; Morawska, Marta M; Imbach, Lukas L; Baumann, Christian R

2018-01-01

Although sleep-wake disturbances are prevalent and well described after traumatic brain injury, their pathophysiology remains unclear, most likely because human traumatic brain injury is a highly heterogeneous entity that makes the systematic study of sleep-wake disturbances in relation to trauma-induced histological changes a challenging task. Despite increasing interest, specific and effective treatment strategies for post-traumatic sleep-wake disturbances are still missing. With the present work, therefore, we aimed at studying acute and chronic sleep-wake disturbances by electrophysiological means, and at assessing their histological correlates after closed diffuse traumatic brain injury in rats with the ultimate goal of generating a model of post-traumatic sleep-wake disturbances and associated histopathological findings that accurately represents the human condition. We assessed sleep-wake behavior by means of standard electrophysiological recordings before and 1, 7, and 28 days after sham or traumatic brain injury procedures. Sleep-wake findings were then correlated to immunohistochemically labeled and stereologically quantified neuronal arousal systems. Compared with control animals, we found that closed diffuse traumatic brain injury caused increased sleep need one month after trauma, and sleep was more consolidated. As histological correlate, we found a reduced number of histamine immunoreactive cells in the tuberomammillary nucleus, potentially related to increased neuroinflammation. Monoaminergic and hypocretinergic neurotransmitter systems in the hypothalamus and rostral brainstem were not affected, however. These results suggest that our rat traumatic brain injury model reflects human post-traumatic sleep-wake disturbances and associated histopathological findings very accurately, thus providing a study platform for novel treatment strategies for affected patients.

Continuous exposure to a novel stressor based on water aversion induces abnormal circadian locomotor rhythms and sleep-wake cycles in mice.

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Koyomi Miyazaki

Full Text Available Psychological stressors prominently affect diurnal rhythms, including locomotor activity, sleep, blood pressure, and body temperature, in humans. Here, we found that a novel continuous stress imposed by the perpetual avoidance of water on a wheel (PAWW affected several physiological diurnal rhythms in mice. One week of PAWW stress decayed robust circadian locomotor rhythmicity, while locomotor activity was evident even during the light period when the mice are normally asleep. Daytime activity was significantly upregulated, whereas nighttime activity was downregulated, resulting in a low amplitude of activity. Total daily activity gradually decreased with increasing exposure to PAWW stress. The mice could be exposed to PAWW stress for over 3 weeks without adaptation. Furthermore, continuous PAWW stress enhanced food intake, but decreased body weight and plasma leptin levels, indicating that sleep loss and PAWW stress altered the energy balance in these mice. The diurnal rhythm of corticosterone levels was not severely affected. The body temperature rhythm was diurnal in the stressed mice, but significantly dysregulated during the dark period. Plasma catecholamines were elevated in the stressed mice. Continuous PAWW stress reduced the duration of daytime sleep, especially during the first half of the light period, and increased nighttime sleepiness. Continuous PAWW stress also simultaneously obscured sleep/wake and locomotor activity rhythms compared with control mice. These sleep architecture phenotypes under stress are similar to those of patients with insomnia. The stressed mice could be entrained to the light/dark cycle, and when they were transferred to constant darkness, they exhibited a free-running circadian rhythm with a timing of activity onset predicted by the phase of their entrained rhythms. Circadian gene expression in the liver and muscle was unaltered, indicating that the peripheral clocks in these tissues remained intact.

Dopamine agonist suppression of rapid-eye-movement sleep is secondary to sleep suppression mediated via limbic structures

International Nuclear Information System (INIS)

Miletich, R.S.

1985-01-01

The effects of pergolide, a direct dopamine receptor agonist, on sleep and wakefulness, motor behavior and 3 H-spiperone specific binding in limbic structures and striatum in rats was studied. The results show that pergolide induced a biphasic dose effect, with high doses increasing wakefulness and suppressing sleep while low dose decreased wakefulness, but increased sleep. It was shown that pergolide-induced sleep suppression was blocked by α-glupenthixol and pimozide, two dopamine receptor antagonists. It was further shown that pergolide merely delayed the rebound resulting from rapid-eye-movement (REM) sleep deprivation, that dopamine receptors stimulation had no direct effect on the period, phase or amplitude of the circadian rhythm of REM sleep propensity and that there was no alteration in the coupling of REM sleep episodes with S 2 episodes. Rapid-eye-movement sleep deprivation resulted in increased sensitivity to the pergolide-induced wakefulness stimulation and sleep suppression and pergolide-induced motor behaviors of locomotion and head bobbing. 3 H-spiperone specific binding to dopamine receptors was shown to be altered by REM sleep deprivation in the subcortical limbic structures. It is concluded that the REM sleep suppressing action of dopamine receptor stimulation is secondary to sleep suppression per se and not secondary to a unique effect on the REM sleep. Further, it is suggested that the wakefulness stimulating action of dopamine receptor agonists is mediated by activation of the dopamine receptors in the terminal areas of the mesolimbocortical dopamine projection system

Hypocretinergic and cholinergic contributions to sleep-wake disturbances in a mouse model of traumatic brain injury

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Hannah E. Thomasy

2017-01-01

Full Text Available Disorders of sleep and wakefulness occur in the majority of individuals who have experienced traumatic brain injury (TBI, with increased sleep need and excessive daytime sleepiness often reported. Behavioral and pharmacological therapies have limited efficacy, in part, because the etiology of post-TBI sleep disturbances is not well understood. Severity of injuries resulting from head trauma in humans is highly variable, and as a consequence so are their sequelae. Here, we use a controlled laboratory model to investigate the effects of TBI on sleep-wake behavior and on candidate neurotransmitter systems as potential mediators. We focus on hypocretin and melanin-concentrating hormone (MCH, hypothalamic neuropeptides important for regulating sleep and wakefulness, and two potential downstream effectors of hypocretin actions, histamine and acetylcholine. Adult male C57BL/6 mice (n=6–10/group were implanted with EEG recording electrodes and baseline recordings were obtained. After baseline recordings, controlled cortical impact was used to induce mild or moderate TBI. EEG recordings were obtained from the same animals at 7 and 15 days post-surgery. Separate groups of animals (n=6–8/group were used to determine effects of TBI on the numbers of hypocretin and MCH-producing neurons in the hypothalamus, histaminergic neurons in the tuberomammillary nucleus, and cholinergic neurons in the basal forebrain. At 15 days post-TBI, wakefulness was decreased and NREM sleep was increased during the dark period in moderately injured animals. There were no differences between groups in REM sleep time, nor were there differences between groups in sleep during the light period. TBI effects on hypocretin and cholinergic neurons were such that more severe injury resulted in fewer cells. Numbers of MCH neurons and histaminergic neurons were not altered under the conditions of this study. Thus, we conclude that moderate TBI in mice reduces wakefulness and increases

Alpha reactivity to complex sounds differs during REM sleep and wakefulness.

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Perrine Ruby

Full Text Available We aimed at better understanding the brain mechanisms involved in the processing of alerting meaningful sounds during sleep, investigating alpha activity. During EEG acquisition, subjects were presented with a passive auditory oddball paradigm including rare complex sounds called Novels (the own first name - OWN, and an unfamiliar first name - OTHER while they were watching a silent movie in the evening or sleeping at night. During the experimental night, the subjects' quality of sleep was generally preserved. During wakefulness, the decrease in alpha power (8-12 Hz induced by Novels was significantly larger for OWN than for OTHER at parietal electrodes, between 600 and 900 ms after stimulus onset. Conversely, during REM sleep, Novels induced an increase in alpha power (from 0 to 1200 ms at all electrodes, significantly larger for OWN than for OTHER at several parietal electrodes between 700 and 1200 ms after stimulus onset. These results show that complex sounds have a different effect on the alpha power during wakefulness (decrease and during REM sleep (increase and that OWN induce a specific effect in these two states. The increased alpha power induced by Novels during REM sleep may 1 correspond to a short and transient increase in arousal; in this case, our study provides an objective measure of the greater arousing power of OWN over OTHER, 2 indicate a cortical inhibition associated with sleep protection. These results suggest that alpha modulation could participate in the selection of stimuli to be further processed during sleep.

Participation of the cholinergic system in the ethanol-induced suppression of paradoxical sleep in rats

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L.A. Papale

2008-09-01

Full Text Available Sleep disturbance is among the many consequences of ethanol abuse in both humans and rodents. Ethanol consumption can reduce REM or paradoxical sleep (PS in humans and rats, respectively. The first aim of this study was to develop an animal model of ethanol-induced PS suppression. This model administered intragastrically (by gavage to male Wistar rats (3 months old, 200-250 g 0.5 to 3.5 g/kg ethanol. The 3.5 g/kg dose of ethanol suppressed the PS stage compared with the vehicle group (distilled water during the first 2-h interval (0-2 h; 1.3 vs 10.2; P < 0.001. The second aim of this study was to investigate the mechanisms by which ethanol suppresses PS. We examined the effects of cholinergic drug pretreatment. The cholinergic system was chosen because of the involvement of cholinergic neurotransmitters in regulating the sleep-wake cycle. A second set of animals was pretreated with 2.5, 5.0, and 10 mg/kg pilocarpine (cholinergic agonist or atropine (cholinergic antagonist. These drugs were administered 1 h prior to ethanol (3.5 g/kg or vehicle. Treatment with atropine prior to vehicle or ethanol produced a statistically significant decrease in PS, whereas pilocarpine had no effect on minutes of PS. Although the mechanism by which ethanol induces PS suppression is not fully understood, these data suggest that the cholinergic system is not the only system involved in this interaction.

Sleep in Children and Adolescents with Angelman Syndrome: Association with Parent Sleep and Stress

Science.gov (United States)

Goldman, S. E.; Bichell, T. J.; Surdyka, K.; Malow, B. A.

2012-01-01

Background: Sleep concerns are common in children with Angelman syndrome, with 20-80% of individuals having a decreased sleep need and/or abnormal sleep-wake cycles. The impact of these sleep behaviours on parental sleep and stress is not known. Method: Through the use of standardised questionnaires, wrist actigraphy and polysomnography, we…

Consciousness across Sleep and Wake: Discontinuity and Continuity of Memory Experiences As a Reflection of Consolidation Processes

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Caroline L. Horton

2017-09-01

Full Text Available The continuity hypothesis (1 posits that there is continuity, of some form, between waking and dreaming mentation. A recent body of work has provided convincing evidence for different aspects of continuity, for instance that some salient experiences from waking life seem to feature in dreams over others, with a particular role for emotional arousal as accompanying these experiences, both during waking and while asleep. However, discontinuities have been somewhat dismissed as being either a product of activation-synthesis, an error within the consciousness binding process during sleep, a methodological anomaly, or simply as yet unexplained. This paper presents an overview of discontinuity within dreaming and waking cognition, arguing that disruptions of consciousness are as common a feature of waking cognition as of dreaming cognition, and that processes of sleep-dependent memory consolidation of autobiographical experiences can in part account for some of the discontinuities of sleeping cognition in a functional way. By drawing upon evidence of the incorporation, fragmentation, and reorganization of memories within dreams, this paper proposes a model of discontinuity whereby the fragmentation of autobiographical and episodic memories during sleep, as part of the consolidation process, render salient aspects of those memories subsequently available for retrieval in isolation from their contextual features. As such discontinuity of consciousness in sleep is functional and normal.

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

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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.

Effects of a newly developed potent orexin-2 receptor-selective antagonist Compound1m on sleep/wake states in mice

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Keishi eEtori

2014-01-01

Full Text Available Orexins (also known as hypocretins, which are hypothalamic neuropeptides, play critical roles in the regulation of sleep/wakefulness states by activating two G-protein coupled receptors (GPCRs, orexin 1 (OX1R and orexin 2 receptors (OX2R. In order to know the difference between effects of OX2R-selective antagonists (2-SORA and dual orexin receptor antagonists (DORA, and to understand the mechanisms underlying orexin-mediated regulation of sleep/wakefulness states, we examined the effects of a newly developed 2-SORA, Compound 1m (C1m, and a DORA, suvorexant, on sleep/wakefulness states in C57BL/6J mice. After oral administration in the dark period, both C1m and suvorexant exhibited potent sleep-promoting properties with similar efficacy in a dose-dependent manner. While C1m did not increase NREM and REM sleep episode durations, suvorexant induced longer episode durations of NREM and REM sleep as compared with both the vehicle- and C1m-administered groups. When compounds were injected during light period, C1m did not show a significant change in sleep/wakefulness states in the light period, whereas suvorexant slightly but significantly increased the sleep time. We also found that C1m did not affect the time of REM sleep, while suvorexant markedly increased it. This suggests that although OX1R-mediated pathway plays a pivotal role in promoting wakefulness, OX1R-mediated pathway also plays an additional role. OX1R-mediated pathway also plays a role in suppression of REM sleep. Fos-immunostaining showed that both compounds affected the activity of arousal-related neurons with different patterns. These results suggest partly overlapping and partly distinct roles of orexin receptors in the regulation of sleep/wakefulness states.

Hypnagogic behavior disorder: complex motor behaviors during wake-sleep transitions in 2 young children.

Science.gov (United States)

Pareja, Juan A; Cuadrado, María Luz; García-Morales, Irene; Gil-Nagel, Antonio; Franch, Oriol

2008-08-01

A nondescribed behavioral disorder was observed during wake-sleep transitions in 2 young children. Two boys had episodes of abnormal behavior in hypnagogic-and occasionally hypnopompic-periods for 1 year from the time they were 1 year and several months old. The episodes consisted of irregular body movements, which could be either gentle or violent but never made the children get out of bed. They lasted from a few seconds to 2 hours and were associated with poor reactivity and amnesia of the events. Electroencephalography (EEG) recordings showed wake-state features, with brief bursts of hypnagogic hypersynchrony, and did not display seizure activity. A distinctive behavior disorder occurring during wake-sleep transitions with a wake EEG pattern has been identified in very early childhood. The clinical profile does not fit any of the known parasomnias and might belong to a new category of parasomnia.

Evaluating the impact of treatment for sleep/wake disorders on recovery of cognition and communication in adults with chronic TBI.

Science.gov (United States)

Wiseman-Hakes, Catherine; Murray, Brian; Moineddin, Rahim; Rochon, Elizabeth; Cullen, Nora; Gargaro, Judith; Colantonio, Angela

2013-01-01

To longitudinally examine objective and self-reported outcomes for recovery of cognition, communication, mood and participation in adults with traumatic brain injury (TBI) and co-morbid post-traumatic sleep/wake disorders. Prospective, longitudinal, single blind outcome study. Community-based. Ten adults with moderate-severe TBI and two adults with mild TBI and persistent symptoms aged 18-58 years. Six males and six females, who were 1-22 years post-injury and presented with self-reported sleep/wake disturbances with onset post-injury. Individualized treatments for sleep/wake disorders that included sleep hygiene recommendations, pharmacological interventions and/or treatments for sleep apnea with follow-up. Insomnia Severity Index, Beck Depression and Anxiety Inventories, Latrobe Communication Questionnaire, Speed and Capacity of Language Processing, Test of Everyday Attention, Repeatable Battery for the Assessment of Neuropsychological Status, Daily Cognitive-Communication and Sleep Profile. Group analysis revealed positive trends in change for each measure and across sub-tests of all measures. Statistically significant changes were noted in insomnia severity, p = 0.0003; depression severity, p = 0.03; language, p = 0.01; speed of language processing, p = 0.007. These results add to a small but growing body of evidence that sleep/wake disorders associated with TBI exacerbate trauma-related cognitive, communication and mood impairments. Treatment for sleep/wake disorders may optimize recovery and outcomes.

Dopamine agonist suppression of rapid-eye-movement sleep is secondary to sleep suppression mediated via limbic structures

Energy Technology Data Exchange (ETDEWEB)

Miletich, R.S.

1985-01-01

The effects of pergolide, a direct dopamine receptor agonist, on sleep and wakefulness, motor behavior and /sup 3/H-spiperone specific binding in limbic structures and striatum in rats was studied. The results show that pergolide induced a biphasic dose effect, with high doses increasing wakefulness and suppressing sleep while low dose decreased wakefulness, but increased sleep. It was shown that pergolide-induced sleep suppression was blocked by ..cap alpha..-glupenthixol and pimozide, two dopamine receptor antagonists. It was further shown that pergolide merely delayed the rebound resulting from rapid-eye-movement (REM) sleep deprivation, that dopamine receptors stimulation had no direct effect on the period, phase or amplitude of the circadian rhythm of REM sleep propensity and that there was no alteration in the coupling of REM sleep episodes with S/sub 2/ episodes. Rapid-eye-movement sleep deprivation resulted in increased sensitivity to the pergolide-induced wakefulness stimulation and sleep suppression and pergolide-induced motor behaviors of locomotion and head bobbing. /sup 3/H-spiperone specific binding to dopamine receptors was shown to be altered by REM sleep deprivation in the subcortical limbic structures. It is concluded that the REM sleep suppressing action of dopamine receptor stimulation is secondary to sleep suppression per se and not secondary to a unique effect on the REM sleep. Further, it is suggested that the wakefulness stimulating action of dopamine receptor agonists is mediated by activation of the dopamine receptors in the terminal areas of the mesolimbocortical dopamine projection system.

Sleep-wake and melatonin pattern in craniopharyngioma patients.

Science.gov (United States)

Pickering, Line; Jennum, Poul; Gammeltoft, Steen; Poulsgaard, Lars; Feldt-Rasmussen, Ulla; Klose, Marianne

2014-06-01

To assess the influence of craniopharyngioma or consequent surgery on melatonin secretion, and the association with fatigue, sleepiness, sleep pattern and sleep quality. Cross-sectional study. A total of 15 craniopharyngioma patients were individually matched to healthy controls. In this study, 24-h salivary melatonin and cortisol were measured. Sleep-wake patterns were characterised by actigraphy and sleep diaries recorded for 2 weeks. Sleepiness, fatigue, sleep quality and general health were assessed by Multidimensional Fatigue Inventory, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale and Short-Form 36. Patients had increased mental fatigue, daytime dysfunction, sleep latency and lower general health (all, P≤0.05), and they tended to have increased daytime sleepiness, general fatigue and impaired sleep quality compared with controls. The degree of hypothalamic injury was associated with an increased BMI and lower mental health (P=0.01). High BMI was associated with increased daytime sleepiness, daytime dysfunction, mental fatigue and lower mental health (all, P≤0.01). Low midnight melatonin was associated with reduced sleep time and efficiency (P≤0.03) and a tendency for increased sleepiness, impaired sleep quality and physical health. Midnight melatonin remained independently related to sleep time after adjustment for cortisol. Three different patterns of melatonin profiles were observed; normal (n=6), absent midnight peak (n=6) and phase-shifted peak (n=2). Only patients with absent midnight peak had impaired sleep quality, increased daytime sleepiness and general and mental fatigue. Craniopharyngioma patients present with changes in circadian pattern and daytime symptoms, which may be due to the influence of the craniopharyngioma or its treatment on the hypothalamic circadian and sleep regulatory nuclei. © 2014 European Society of Endocrinology.

Effects of light exposure and sleep displacement on dim light melatonin onset

NARCIS (Netherlands)

Gordijn, MCM; Beersma, DGM; Korte, HJ; Van den Hoofdakker, RH

The purpose of the study was to induce in two different ways, a phase-angle difference between the circadian pacemaker and the imposed sleep-wake cycle in humans, we intended to: (i) shift the circadian pacemaker by exposure to bright light and keep the timing of the sleep-wake cycle fixed; and (ii)

Managing sleep and wakefulness in a 24-hour world.

Science.gov (United States)

Coveney, Catherine M

2014-01-01

This article contributes to literature on the sociology of sleep by exploring the sleeping practices and subjective sleep experiences of two social groups: shift workers and students. It draws on data, collected in the UK from 25 semi-structured interviews, to discuss the complex ways in which working patterns and social activities impact upon experiences and expectations of sleep in our wired awake world. The data show that, typically, sleep is valued and considered to be important for health, general wellbeing, appearance and physical and cognitive functioning. However, sleep time is often cut back on in favour of work demands and social activities. While shift workers described their efforts to fit in an adequate amount of sleep per 24-hour period, for students, the adoption of a flexible sleep routine was thought to be favourable for maintaining a work-social life balance. Collectively, respondents reported using a wide range of strategies, techniques, technologies and practices to encourage, overcome or delay sleep(iness) and boost, promote or enhance wakefulness/alertness at socially desirable times. The analysis demonstrates how social context impacts not only on how we come to think about sleep and understand it, but also how we manage or self-regulate our sleeping patterns. © 2013 The Author. Sociology of Health & Illness © 2013 Foundation for the Sociology of Health & Illness/John Wiley & Sons Ltd.

Electroencephalogram Power Density and Slow Wave Sleep as a Function of Prior Waking and Circadian Phase

NARCIS (Netherlands)

Dijk, Derk-Jan; Brunner, Daniel P.; Beersma, Domien G.M.; Borbély, Alexander A.

1990-01-01

Human sleep electroencephalograms, recorded in four experiments, were subjected to spectral analysis. Waking prior to sleep varied from 12 to 36 h and sleep was initiated at different circadian phases. Power density of delta and theta frequencies in rapid-eye-movement (REM) sleep and non-REM (NREM)

Effect of sleep deprivation on the epithelial height of the prostatic acini in rats and the protective effects of omega 3 fatty acids

International Nuclear Information System (INIS)

Mahmood, N.; Butt, S.A.; Hamid, S.

2017-01-01

Objective: To study the protective role of omega 3 fatty acids (omg 3 FAs) on the histomorphological changes in the height of the prostatic epithelium in rats induced by sleep deprivation. Study Design: Lab based randomized control trial. Place and Duration of Study: The study was conducted at Anatomy Department, Army Medical College, Rawalpindi, in collaboration with National Institute of Health (NIH), Rawalpindi for duration of one year, from Nov 2014 to Nov 2015. Material and Methods: Thirty male Sprague Dawley rats, 3-4 months of age with average weights of 200-300 grams (gm) were divided in three groups each having 10 rats. Group A served as control with standard lab diet and regular sleep -wake cycle. Group B was subjected to sleep deprivation of 16 hours followed by a sleep window of 8 hrs daily for 2 months and group C was administrated with omg 3 fatty acids (FAs) and was sleep deprived as group B for 2 months. At the end of the experimental period rats were anesthetized and their blood sample was drawn for hormonal assay. They were dissected and the prostate gland was removed and fixed in 10 percent formalin. Five micrometer (mu m) sections were obtained after tissue processing and stained with haematoxylin and eosin (H and E) for histological study. Results: Microscopic examination revealed that the epithelium of glandular acini was columnar in group A. Marked decrease in the height of cells was observed in group B whereas the epithelium was nearly cuboidal in group C. Conclusion: It was concluded that sleep deprivation had deleterious effects on the epithelium of the prostatic acini and that Omega 3 fatty acids had a protective effect on the epithelium of the prostatic acini. (author)

Sleep Deprivation Influences Circadian Gene Expression in the Lateral Habenula.

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Zhang, Beilin; Gao, Yanxia; Li, Yang; Yang, Jing; Zhao, Hua

2016-01-01

Sleep is governed by homeostasis and the circadian clock. Clock genes play an important role in the generation and maintenance of circadian rhythms but are also involved in regulating sleep homeostasis. The lateral habenular nucleus (LHb) has been implicated in sleep-wake regulation, since LHb gene expression demonstrates circadian oscillation characteristics. This study focuses on the participation of LHb clock genes in regulating sleep homeostasis, as the nature of their involvement is unclear. In this study, we observed changes in sleep pattern following sleep deprivation in LHb-lesioned rats using EEG recording techniques. And then the changes of clock gene expression (Per1, Per2, and Bmal1) in the LHb after 6 hours of sleep deprivation were detected by using real-time quantitative PCR (qPCR). We found that sleep deprivation increased the length of Non-Rapid Eye Movement Sleep (NREMS) and decreased wakefulness. LHb-lesioning decreased the amplitude of reduced wake time and increased NREMS following sleep deprivation in rats. qPCR results demonstrated that Per2 expression was elevated after sleep deprivation, while the other two genes were unaffected. Following sleep recovery, Per2 expression was comparable to the control group. This study provides the basis for further research on the role of LHb Per2 gene in the regulation of sleep homeostasis.

Early and Later Life Stress Alter Brain Activity and Sleep in Rats

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Mrdalj, Jelena; Pallesen, Ståle; Milde, Anne Marita; Jellestad, Finn Konow; Murison, Robert; Ursin, Reidun; Bjorvatn, Bjørn; Grønli, Janne

2013-01-01

Exposure to early life stress may profoundly influence the developing brain in lasting ways. Neuropsychiatric disorders associated with early life adversity may involve neural changes reflected in EEG power as a measure of brain activity and disturbed sleep. The main aim of the present study was for the first time to characterize possible changes in adult EEG power after postnatal maternal separation in rats. Furthermore, in the same animals, we investigated how EEG power and sleep architecture were affected after exposure to a chronic mild stress protocol. During postnatal day 2–14 male rats were exposed to either long maternal separation (180 min) or brief maternal separation (10 min). Long maternally separated offspring showed a sleep-wake nonspecific reduction in adult EEG power at the frontal EEG derivation compared to the brief maternally separated group. The quality of slow wave sleep differed as the long maternally separated group showed lower delta power in the frontal-frontal EEG and a slower reduction of the sleep pressure. Exposure to chronic mild stress led to a lower EEG power in both groups. Chronic exposure to mild stressors affected sleep differently in the two groups of maternal separation. Long maternally separated offspring showed more total sleep time, more episodes of rapid eye movement sleep and higher percentage of non-rapid eye movement episodes ending in rapid eye movement sleep compared to brief maternal separation. Chronic stress affected similarly other sleep parameters and flattened the sleep homeostasis curves in all offspring. The results confirm that early environmental conditions modulate the brain functioning in a long-lasting way. PMID:23922857

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.

The perilipin homologue, lipid storage droplet 2, regulates sleep homeostasis and prevents learning impairments following sleep loss.

Directory of Open Access Journals (Sweden)

Matthew S Thimgan

2010-08-01

Full Text Available Extended periods of waking result in physiological impairments in humans, rats, and flies. Sleep homeostasis, the increase in sleep observed following sleep loss, is believed to counter the negative effects of prolonged waking by restoring vital biological processes that are degraded during sleep deprivation. Sleep homeostasis, as with other behaviors, is influenced by both genes and environment. We report here that during periods of starvation, flies remain spontaneously awake but, in contrast to sleep deprivation, do not accrue any of the negative consequences of prolonged waking. Specifically, the homeostatic response and learning impairments that are a characteristic of sleep loss are not observed following prolonged waking induced by starvation. Recently, two genes, brummer (bmm and Lipid storage droplet 2 (Lsd2, have been shown to modulate the response to starvation. bmm mutants have excess fat and are resistant to starvation, whereas Lsd2 mutants are lean and sensitive to starvation. Thus, we hypothesized that bmm and Lsd2 may play a role in sleep regulation. Indeed, bmm mutant flies display a large homeostatic response following sleep deprivation. In contrast, Lsd2 mutant flies, which phenocopy aspects of starvation as measured by low triglyceride stores, do not exhibit a homeostatic response following sleep loss. Importantly, Lsd2 mutant flies are not learning impaired after sleep deprivation. These results provide the first genetic evidence, to our knowledge, that lipid metabolism plays an important role in regulating the homeostatic response and can protect against neuronal impairments induced by prolonged waking.

Cellular consequences of sleep deprivation in the brain.

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Cirelli, Chiara

2006-10-01

Several recent studies have used transcriptomics approaches to characterize the molecular correlates of sleep, waking, and sleep deprivation. This analysis may help in understanding the benefits that sleep brings to the brain at the cellular level. The studies are still limited in number and focus on a few brain regions, but some consistent findings are emerging. Sleep, spontaneous wakefulness, short-term, and long-term sleep deprivation are each associated with the upregulation of hundreds of genes in the cerebral cortex and other brain areas. In fruit flies as well as in mammals, three categories of genes are consistently upregulated during waking and short-term sleep deprivation relative to sleep. They include genes involved in energy metabolism, synaptic potentiation, and the response to cellular stress. In the rat cerebral cortex, transcriptional changes associated with prolonged sleep loss differ significantly from those observed during short-term sleep deprivation. However, it is too early to draw firm conclusions relative to the molecular consequences of sleep deprivation, and more extensive studies using DNA and protein arrays are needed in different species and in different brain regions.

Sleep-wake patterns and their influence on school performance in Portuguese adolescents

OpenAIRE

Duarte, João; Nelas, Paula; Chaves, Cláudia; Ferreira, Manuela; Coutinho, Emília; Cunha, Madalena

2014-01-01

Objective: To characterise sleep-wake patterns and their influence on academic performance for a sample of Portuguese adolescents. Research design: Cross-sectional, analytical-explanatory, correlational epidemiological research. The protocol includes the composite morningness questionnaire (Barton et al, 1985 adapted by Silva et al, 1985), the Epworth Sleepiness Scale (Murray, 1991), chronic fatigue scale (Smith et al, 1995), the Pittsburgh Sleep Quality Index (Buysse, 1988), Educational A...

Dynamic changes in GABAA receptors on basal forebrain cholinergic neurons following sleep deprivation and recovery

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Jones Barbara E

2007-02-01

Full Text Available Abstract Background The basal forebrain (BF cholinergic neurons play an important role in cortical activation and arousal and are active in association with cortical activation of waking and inactive in association with cortical slow wave activity of sleep. In view of findings that GABAA receptors (Rs and inhibitory transmission undergo dynamic changes as a function of prior activity, we investigated whether the GABAARs on cholinergic cells might undergo such changes as a function of their prior activity during waking vs. sleep. Results In the brains of rats under sleep control (SC, sleep deprivation (SD or sleep recovery (SR conditions in the 3 hours prior to sacrifice, we examined immunofluorescent staining for β2–3 subunit GABAARs on choline acetyltransferase (ChAT immunopositive (+ cells in the magnocellular BF. In sections also stained for c-Fos, β2–3 GABAARs were present on ChAT+ neurons which expressed c-Fos in the SD group alone and were variable or undetectable on other ChAT+ cells across groups. In dual-immunostained sections, the luminance of β2–3 GABAARs over the membrane of ChAT+ cells was found to vary significantly across conditions and to be significantly higher in SD than SC or SR groups. Conclusion We conclude that membrane GABAARs increase on cholinergic cells as a result of activity during sustained waking and reciprocally decrease as a result of inactivity during sleep. These changes in membrane GABAARs would be associated with increased GABA-mediated inhibition of cholinergic cells following prolonged waking and diminished inhibition following sleep and could thus reflect a homeostatic process regulating cholinergic cell activity and thereby indirectly cortical activity across the sleep-waking cycle.

Perifornical orexinergic neurons modulate REM sleep by influencing locus coeruleus neurons in rats.

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Choudhary, R C; Khanday, M A; Mitra, A; Mallick, B N

2014-10-24

Activation of the orexin (OX)-ergic neurons in the perifornical (PeF) area has been reported to induce waking and reduce rapid eye movement sleep (REMS). The activities of OX-ergic neurons are maximum during active waking and they progressively reduce during non-REMS (NREMS) and REMS. Apparently, the locus coeruleus (LC) neurons also behave in a comparable manner as that of the OX-ergic neurons particularly in relation to waking and REMS. Further, as PeF OX-ergic neurons send dense projections to LC, we argued that the former could drive the LC neurons to modulate waking and REMS. Studies in freely moving normally behaving animals where simultaneously neuro-chemo-anatomo-physio-behavioral information could be deciphered would significantly strengthen our understanding on the regulation of REMS. Therefore, in this study in freely behaving chronically prepared rats we stimulated the PeF neurons without or with simultaneous blocking of specific subtypes of OX-ergic receptors in the LC while electrophysiological recording characterizing sleep-waking was continued. Single dose of glutamate stimulation as well as sustained mild electrical stimulation of PeF (both bilateral) significantly increased waking and reduced REMS as compared to baseline. Simultaneous application of OX-receptor1 (OX1R) antagonist bilaterally into the LC prevented PeF stimulation-induced REMS suppression. Also, the effect of electrical stimulation of the PeF was long lasting as compared to that of the glutamate stimulation. Further, sustained electrical stimulation significantly decreased both REMS duration as well as REMS frequency, while glutamate stimulation decreased REMS duration only. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Temporal correlation between two channels EEG of bipolar lead in the head midline is associated with sleep-wake stages.

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Li, Yanjun; Tang, Xiaoying; Xu, Zhi; Liu, Weifeng; Li, Jing

2016-03-01

Whether the temporal correlation between inter-leads Electroencephalogram (EEG) that located on the boundary between left and right brain hemispheres is associated with sleep stages or not is still unknown. The purpose of this paper is to evaluate the role of correlation coefficients between EEG leads Fpz-Cz and Pz-Oz for automatic classification of sleep stages. A total number of 39 EEG recordings (about 20 h each) were selected from the expanded sleep database in European data format for temporal correlation analysis. Original waveform of EEG was decomposed into sub-bands δ (1-4 Hz), θ (4-8 Hz), α (8-13 Hz) and β (13-30 Hz). The correlation coefficient between original EEG leads Fpz-Cz and Pz-Oz within frequency band 0.5-30 Hz was defined as r(EEG) and was calculated every 30 s, while that between the two leads EEG in sub-bands δ, θ, α and β were defined as r(δ), r(θ), r(α) and r(β), respectively. Classification of wakefulness and sleep was processed by fixed threshold that derived from the probability density function of correlation coefficients. There was no correlation between EEG leads Fpz-Cz and Pz-Oz during wakefulness (|r| r > 0.1 for r(EEG) and r(δ)), while low correlation existed during sleep (r ≈ -0.4 for r(EEG), r(δ), r(θ), r(α) and r(β)). There were significant differences (analysis of variance, P correlation index between EEG leads Fpz-Cz and Pz-Oz could distinguish all five types of wakefulness, rapid eye movement (REM) sleep, N1 sleep, N2 sleep and N3 sleep. In conclusion, the temporal correlation between EEG bipolar leads Fpz-Cz and Pz-Oz are highly associated with sleep-wake stages. Moreover, high accuracy of sleep-wake classification could be achieved by the temporal correlation within frequency band 0.5-30 Hz between EEG leads Fpz-Cz and Pz-Oz.

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.

2014-01-01

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

Work hours and sleep/wake behavior of Australian hospital doctors.

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Ferguson, Sally A; Thomas, Matthew J W; Dorrian, Jillian; Jay, Sarah M; Weissenfeld, Adrian; Dawson, Drew

2010-07-01

The objective of the study was to describe the work and sleep patterns of doctors working in Australian hospitals. Specifically, the aim was to examine the influence of work-related factors, such as hospital type, seniority, and specialty on work hours and their impact on sleep. A total of 635 work periods from 78 doctors were analyzed together with associated sleep history. Work and sleep diary information was validated against an objective measure of sleep/wake activity to provide the first comprehensive database linking work and sleep for individual hospital doctors in Australia. Doctors in large and small facilities had fewer days without work than those doctors working in medium-sized facilities. There were no significant differences in the total hours worked across these three categories of seniority; however, mid-career and senior doctors worked more overnight and weekend on-call periods than junior doctors. With respect to sleep, although higher work hours were related to less sleep, short sleeps (work) were observed at all levels of prior work history (including no work). In this population of Australian hospital doctors, total hours worked do impact sleep, but the pattern of work, together with other nonwork factors are also important mediators.

Neural Damage in Experimental Trypanosoma brucei gambiense Infection: Hypothalamic Peptidergic Sleep and Wake-Regulatory Neurons

Directory of Open Access Journals (Sweden)

Claudia Laperchia

2018-02-01

Full Text Available Neuron populations of the lateral hypothalamus which synthesize the orexin (OX/hypocretin or melanin-concentrating hormone (MCH peptides play crucial, reciprocal roles in regulating wake stability and sleep. The disease human African trypanosomiasis (HAT, also called sleeping sickness, caused by extracellular Trypanosoma brucei (T. b. parasites, leads to characteristic sleep-wake cycle disruption and narcoleptic-like alterations of the sleep structure. Previous studies have revealed damage of OX and MCH neurons during systemic infection of laboratory rodents with the non-human pathogenic T. b. brucei subspecies. No information is available, however, on these peptidergic neurons after systemic infection with T. b. gambiense, the etiological agent of 97% of HAT cases. The present study was aimed at the investigation of immunohistochemically characterized OX and MCH neurons after T. b. gambiense or T. b. brucei infection of a susceptible rodent, the multimammate mouse, Mastomysnatalensis. Cell counts and evaluation of OX fiber density were performed at 4 and 8 weeks post-infection, when parasites had entered the brain parenchyma from the periphery. A significant decrease of OX neurons (about 44% reduction and MCH neurons (about 54% reduction was found in the lateral hypothalamus and perifornical area at 8 weeks in T. b. gambiense-infected M. natalensis. A moderate decrease (21% and 24% reduction, respectively, which did not reach statistical significance, was found after T. b. brucei infection. In two key targets of diencephalic orexinergic innervation, the peri-suprachiasmatic nucleus (SCN region and the thalamic paraventricular nucleus (PVT, densitometric analyses showed a significant progressive decrease in the density of orexinergic fibers in both infection paradigms, and especially during T. b. gambiense infection. Altogether the findings provide novel information showing that OX and MCH neurons are highly vulnerable to chronic

Sleep deprivation: consequences for students.

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Marhefka, Julie King

2011-09-01

During the adolescent years, a delayed pattern of the sleep-wake cycle occurs. Many parents and health care providers are not aware that once established, these poor sleep habits can continue into adulthood. Early school hours start a pattern of sleep loss that begins a cycle of daytime sleepiness, which may affect mood, behavior, and increase risk for accidents or injury. These sleep-deprived habits established in adolescence can often lead to problems during college years. Sleep hygiene can be initiated to help break the cycle, along with education and implementation of a strict regimen. Monitoring all adolescents and college-aged students for sleep insufficiency is imperative to improve both academic and emotional well-being. Copyright 2011, SLACK Incorporated.

Sleep-wake habits in middle and late adolescence and the criteria for the choice of subjects on sleep research

OpenAIRE

林, 光緒; 田中, 秀樹; 岩城, 達也; 福田, 一彦; 堀, 忠雄

1997-01-01

Sleep-wake habits in middle and late adolescence were surveyed for college of technology (n=799), college of nursing (n=460) and university (n=1062) students. Daytime sleepiness and nodding off were often occurred. They made up for shortened sleep time at holiday. One third of them took replacement naps. Some of them had the irregular life habits, such as delayed bed-time, shortened sleep time, irregular meal time and engaging in night work, suggesting that these habits might alter the phase ...

Roles of the hypocretin/orexins in the regulation of sleep and wakefulness.

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Terao, Akira; Haruyama, Takashi; Kimura, Kazuhiro

2008-01-01

Hypocretin/orexin is produced exclusively in the dorsal and lateral hypothalamus but its projection is widespread within the brain and plays important roles. In this paper, we review the independent discoveries of the hypocretin/orexin peptides, the neuroanatomy of this system, and the link to the sleep disorder narcolepsy that has led to the idea that this system plays a crucial role in the regulation of sleep and wakefulness.

REM sleep modulation by perifornical orexinergic inputs to the pedunculo-pontine tegmental neurons in rats.

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Khanday, M A; Mallick, B N

2015-11-12

Rapid eye movement sleep (REMS) is regulated by the interaction of the REM-ON and REM-OFF neurons located in the pedunculo-pontine-tegmentum (PPT) and the locus coeruleus (LC), respectively. Many other brain areas, particularly those controlling non-REMS (NREMS) and waking, modulate REMS by modulating these REMS-related neurons. Perifornical (PeF) orexin (Ox)-ergic neurons are reported to increase waking and reduce NREMS as well as REMS; dysfunction of the PeF neurons are related to REMS loss-associated disorders. Hence, we were interested in understanding the neural mechanism of PeF-induced REMS modulation. As a first step we have recently reported that PeF Ox-ergic neurons modulate REMS by influencing the LC neurons (site for REM-OFF neurons). Thereafter, in this in vivo study we have explored the role of PeF inputs on the PPT neurons (site for REM-ON neurons) for the regulation of REMS. Chronic male rats were surgically prepared with implanted bilateral cannulae in PeF and PPT and electrodes for recording sleep-waking patterns. After post-surgical recovery sleep-waking-REMS were recorded when bilateral PeF neurons were stimulated by glutamate and simultaneously bilateral PPT neurons were infused with either saline or orexin receptor1 (OX1R) antagonist. It was observed that PeF stimulation increased waking and decreased NREMS as well as REMS, which were prevented by OX1R antagonist into the PPT. We conclude that the PeF stimulation-induced reduction in REMS was likely to be due to inhibition of REM-ON neurons in the PPT. As waking and NREMS are inversely related, subject to confirmation, the reduction in NREMS could be due to increased waking or vice versa. Based on our findings from this and earlier studies we have proposed a model showing connections between PeF- and PPT-neurons for REMS regulation. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

Vascular compliance limits during sleep deprivation and recovery sleep.

Science.gov (United States)

Phillips, Derrick J; Schei, Jennifer L; Rector, David M

2013-10-01

Our previous studies showed that evoked hemodynamic responses are smaller during wake compared to sleep; suggesting neural activity is associated with vascular expansion and decreased compliance. We explored whether prolonged activity during sleep deprivation may exacerbate vascular expansion and blunt hemodynamic responses. Evoked auditory responses were generated with periodic 65 dB speaker clicks over a 72-h period and measured with cortical electrodes. Evoked hemodynamic responses were measured simultaneously with optical techniques using three light-emitting diodes, and a photodiode. Animals were housed in separate 30×30×80 cm enclosures, tethered to a commutator system and maintained on a 12-h light/dark cycle. Food and water were available ad libitum. Seven adult female Sprague-Dawley rats. Following a 24-h baseline recording, sleep deprivation was initiated for 0 to 10 h by gentle handling, followed by a 24-h recovery sleep recording. Evoked electrical and hemodynamic responses were measured before, during, and after sleep deprivation. Following deprivation, evoked hemodynamic amplitudes were blunted. Steady-state oxyhemoglobin concentration increased during deprivation and remained high during the initial recovery period before returning to baseline levels after approximately 9-h. Sleep deprivation resulted in blood vessel expansion and decreased compliance while lower basal neural activity during recovery sleep may allow blood vessel compliance to recover. Chronic sleep restriction or sleep deprivation could push the vasculature to critical levels, limiting blood delivery, and leading to metabolic deficits with the potential for neural trauma.

Sleep duration, wake/sleep symptoms, and academic performance in Hong Kong Secondary School Children.

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Ng, E P; Ng, D K; Chan, C H

2009-11-01

Sleep deprivation is common among teenagers. The aim of this study was to investigate the relationship between sleep duration, wake/sleep symptoms, and academic performance among Hong Kong students. The sleep habit questionnaires were distributed to all Year 11 students at an international school that catered to different ethnic groups in Hong Kong. Analysis of various parameters of academic performance and sleep habits and their relationships were undertaken. Fifty-nine students were recruited. The average sleep duration in this group was 7.23 h. The overall prevalence of excessive daytime sleepiness (defined as an Epworth Sleepiness Scale score of >10) was 25.4%. Eleven subjects had excessive class sleepiness, defined as high likelihood to fall asleep during at least one school session. Mathematics performance was positively correlated with sleep duration. Excessive sleepiness on rising was identified as a significant risk factor for poor performance in English and Mathematics. Sleepiness during the third and fourth lessons was identified as a significant risk factor for poor performance in Mathematics only. Sleep deprivation was common in the studied cohort and it was associated with a decrease in Mathematics performance. Excessive sleepiness on rising and sleepiness during third and fourth lessons were associated with poorer grades in Mathematics and English. Excessive daytime sleepiness was reported in 25% of students. Bruxism and snoring were associated with excessive daytime sleepiness.

Acute administration of fluoxetine normalizes rapid eye movement sleep abnormality, but not depressive behaviors in olfactory bulbectomized rats.

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Wang, Yi-Qun; Tu, Zhi-Cai; Xu, Xing-Yuan; Li, Rui; Qu, Wei-Min; Urade, Yoshihiro; Huang, Zhi-Li

2012-01-01

In humans, depression is associated with altered rapid eye movement (REM) sleep. However, the exact nature of the relationship between depressive behaviors and sleep abnormalities is debated. In this study, bilateral olfactory bulbectomy (OBX) was carried out to create a model of depression in rats. The sleep-wake profiles were assayed using a cutting-edge sleep bioassay system, and depressive behaviors were evaluated by open field and forced swimming tests. The monoamine content and monoamine metabolite levels in the brain were determined by a HPLC-electrochemical detection system. OBX rats exhibited a significant increase in REM sleep, especially between 15:00 and 18:00 hours during the light period. Acute treatment with fluoxetine (10 mg/kg, i.p.) immediately abolished the OBX-induced increase in REM sleep, but hyperactivity in the open field test and the time spent immobile in the forced swimming test remained unchanged. Neurochemistry studies revealed that acute administration of fluoxetine increased serotonin (5-HT) levels in the hippocampus, thalamus, and midbrain and decreased levels of the 5-HT metabolite 5-hydroxyindoleacetic acid (5-HIAA). The ratio of 5-HIAA to 5-HT decreased in almost all regions of the brain. These results indicate that acute administration of fluoxetine can reduce the increase in REM sleep but does not change the depressive behaviors in OBX rats, suggesting that there was no causality between REM sleep abnormalities and depressive behaviors in OBX rats. © 2011 The Authors. Journal of Neurochemistry © 2011 International Society for Neurochemistry.

A Rodent Model of Night-Shift Work Induces Short-Term and Enduring Sleep and Electroencephalographic Disturbances.

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Grønli, Janne; Meerlo, Peter; Pedersen, Torhild T; Pallesen, Ståle; Skrede, Silje; Marti, Andrea R; Wisor, Jonathan P; Murison, Robert; Henriksen, Tone E G; Rempe, Michael J; Mrdalj, Jelena

2017-02-01

Millions of people worldwide are working at times that overlap with the normal time for sleep. Sleep problems related to the work schedule may mediate the well-established relationship between shift work and increased risk for disease, occupational errors and accidents. Yet, our understanding of causality and the underlying mechanisms that explain this relationship is limited. We aimed to assess the consequences of night-shift work for sleep and to examine whether night-shift work-induced sleep disturbances may yield electrophysiological markers of impaired maintenance of the waking brain state. An experimental model developed in rats simulated a 4-day protocol of night-work in humans. Two groups of rats underwent 8-h sessions of enforced ambulation, either at the circadian time when the animal was physiologically primed for wakefulness (active-workers, mimicking day-shift) or for sleep (rest-workers, mimicking night-shift). The 4-day rest-work schedule induced a pronounced redistribution of sleep to the endogenous active phase. Rest-work also led to higher electroencephalogram (EEG) slow-wave (1-4 Hz) energy in quiet wakefulness during work-sessions, suggesting a degraded waking state. After the daily work-sessions, being in their endogenous active phase, rest-workers slept less and had higher gamma (80-90 Hz) activity during wake than active-workers. Finally, rest-work induced an enduring shift in the main sleep period and attenuated the accumulation of slow-wave energy during NREM sleep. A comparison of recovery data from 12:12 LD and constant dark conditions suggests that reduced time in NREM sleep throughout the recorded 7-day recovery phase induced by rest-work may be modulated by circadian factors. Our data in rats show that enforced night-work-like activity during the normal resting phase has pronounced acute and persistent effects on sleep and waking behavior. The study also underscores the potential importance of animal models for future studies on the

Sleep Changes in a Rat Prenatal Stress Model of Depression

DEFF Research Database (Denmark)

Skoven, Christian; Sickman, Helle M.; Bastlund, Jesper Frank

Major depression is one of the most frequently occurring mental health disorders, but is characterized by diverse symptomatology. Sleep disturbances, however, are commonplace in depressive patients. These alterations include increased duration of Rapid Eye Movement Sleep (REMS) and increased sleep...... determination of sleep-wakefulness state. As traumatic episodes can trigger episodes of clinical depression, we also investigated effects of an acute stressor during the recording period. PNS animals (n=21) had an 82% increase in amount of REMS (11.6±1.4% vs 6.3±0.9%; p...-related increase in REMS after lights-off (pREMS rebound thus seems blunted in PNS animals. PNS alters sleep-wakefulness behavior under baseline conditions and after acute stress. This underscores the value of the PNS...

The wake-promoting hypocretin/orexin neurons change their response to noradrenaline after sleep deprivation.

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Grivel, Jeremy; Cvetkovic, Vesna; Bayer, Laurence; Machard, Danièle; Tobler, Irene; Mühlethaler, Michel; Serafin, Mauro

2005-04-20

Sleep deprivation is accompanied by the progressive development of an irresistible need to sleep, a phenomenon whose mechanism has remained elusive. Here, we identified for the first time a reflection of that phenomenon in vitro by showing that, after a short 2 h period of total sleep deprivation, the action of noradrenaline on the wake-promoting hypocretin/orexin neurons changes from an excitation to an inhibition. We propose that such a conspicuous modification of responsiveness should contribute to the growing sleepiness that accompanies sleep deprivation.

Repeated Sleep Restriction in Adolescent Rats Altered Sleep Patterns and Impaired Spatial Learning/Memory Ability

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Yang, Su-Rong; Sun, Hui; Huang, Zhi-Li; Yao, Ming-Hui; Qu, Wei-Min

2012-01-01

Study Objectives: To investigate possible differences in the effect of repeated sleep restriction (RSR) during adolescence and adulthood on sleep homeostasis and spatial learning and memory ability. Design: The authors examined electroencephalograms of rats as they were subjected to 4-h daily sleep deprivation that continued for 7 consecutive days and assessed the spatial learning and memory by Morris water maze test (WMT). Participants: Adolescent and adult rats. Measurements and Results: Adolescent rats exhibited a similar amount of rapid eye movement (REM) and nonrapid eye movement (NREM) sleep with higher slow wave activity (SWA, 0.5-4 Hz) and fewer episodes and conversions with prolonged durations, indicating they have better sleep quality than adult rats. After RSR, adult rats showed strong rebound of REM sleep by 31% on sleep deprivation day 1; this value was 37% on sleep deprivation day 7 in adolescents compared with 20-h baseline level. On sleep deprivation day 7, SWA in adult and adolescent rats increased by 47% and 33%, and such elevation lasted for 5 h and 7 h, respectively. Furthermore, the authors investigated the effects of 4-h daily sleep deprivation immediately after the water maze training sessions on spatial cognitive performance. Adolescent rats sleep-restricted for 7 days traveled a longer distance to find the hidden platform during the acquisition training and had fewer numbers of platform crossings in the probe trial than those in the control group, something that did not occur in the sleep-deprived adult rats. Conclusions: Repeated sleep restriction (RSR) altered sleep profiles and mildly impaired spatial learning and memory capability in adolescent rats. Citation: Yang SR; Sun H; Huang ZL; Yao MH; Qu WM. Repeated sleep restriction in adolescent rats altered sleep patterns and impaired spatial learning/memory ability. SLEEP 2012;35(6):849-859. PMID:22654204

The effect of extended wake on postural control in young adults.

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Smith, Simon S; Cheng, Tiffany; Kerr, Graham K

2012-09-01

The sleep-wake cycle is a major determinant of locomotor activity in humans, and the neural and physiological processes necessary for optimum postural control may be impaired by an extension of the wake period into habitual sleep time. There is growing evidence for such a contribution from sleep-related factors, but great inconsistency in the methods used to assess this contribution, particularly in control for circadian phase position. Postural control was assessed at hourly intervals across 14 h of extended wake in nine young adult participants. Force plate parameters of medio-lateral and anterior-posterior sway, centre of pressure (CoP) trace length, area, and velocity were assessed with eyes open and eyes closed over 3-min periods. A standard measure of psychomotor vigilance was assessed concurrently under constant routine conditions. After controlling for individual differences in circadian phase position, a significant effect of extended wake was found for anterior-posterior sway and for psychomotor vigilance. These data suggest that extended wake may increase the risk of a fall or other consequences of impaired postural control.

Validation of Actiwatch for Assessment of Sleep-wake States in Preterm Infants

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Shu-Chen Yang, RN, MSN

2014-09-01

Conclusion: Results of this study suggest that high activity thresholds are the most accurate for determining sleep state in preterm infants, and health care professionals must take the limitations into consideration while using the Actiwatch to assess wake states.

Energetic constraints, not predation, influence the evolution of sleep patterning in mammals

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Capellini, I.; Nunn, C. L.; McNamara, P.; Preston, B. T.; Barton, R. A.

2008-01-01

Mammalian sleep is composed of two distinct states – rapid-eye-movement (REM) and non-REM (NREM) sleep – that alternate in cycles over a sleep bout. The duration of these cycles varies extensively across mammalian species. Because the end of a sleep cycle is often followed by brief arousals to waking, a shorter sleep cycle has been proposed to function as an anti-predator strategy. Similarly, higher predation risk could explain why many species exhibit a polyphasic sleep pattern (division of ...

Wake and Sleep EEG in Patients With Huntington Disease: An eLORETA Study and Review of the Literature.

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Piano, Carla; Mazzucchi, Edoardo; Bentivoglio, Anna Rita; Losurdo, Anna; Calandra Buonaura, Giovanna; Imperatori, Claudio; Cortelli, Pietro; Della Marca, Giacomo

2017-01-01

The aim of the study was to evaluate the EEG modifications in patients with Huntington disease (HD) compared with controls, by means of the exact LOw REsolution Tomography (eLORETA) software. We evaluated EEG changes during wake, non-rapid eye movement (NREM) and rapid eye movement (REM) sleep. Moreover, we reviewed the literature concerning EEG modifications in HD. Twenty-three consecutive adult patients affected by HD were enrolled, 14 women and 9 men, mean age was 57.0 ± 12.4 years. Control subjects were healthy volunteers (mean age 58.2 ± 14.6 years). EEG and polygraphic recordings were performed during wake (before sleep) and during sleep. Sources of EEG activities were determined using the eLORETA software. In wake EEG, significant differences between patients and controls were detected in the delta frequency band (threshold T = ±4.606; P < .01) in the Brodmann areas (BAs) 3, 4, and 6 bilaterally. In NREM sleep, HD patients showed increased alpha power (T = ±4.516; P < .01) in BAs 4 and 6 bilaterally; decreased theta power (T = ±4.516; P < .01) in the BAs 23, 29, and 30; and decreased beta power (T = ±4.516; P < .01) in the left BA 30. During REM, HD patients presented decreased theta and alpha power (threshold T = ±4.640; P < .01) in the BAs 23, 29, 30, and 31 bilaterally. In conclusion, EEG data suggest a motor cortex dysfunction during wake and sleep in HD patients, which correlates with the clinical and polysomnographic evidence of increased motor activity during wake and NREM, and nearly absent motor abnormalities in REM. © EEG and Clinical Neuroscience Society (ECNS) 2016.

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.

The suprachiasmatic nucleus regulates sleep timing and amount in mice

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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

Sleep and alertness during alternating monophasic and polyphasic rest-activity cycles.

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Porcú, S; Casagrande, M; Ferrara, M; Bellatreccia, A

1998-07-01

People involved in shift work often have to face altered patterns of sleep and wakefulness. This is particularly true for schedules involving night shifts and/or fragmentation of duty periods throughout the 24-hr day. In such conditions, it can be difficult to obtain satisfactory periods of sleep, and sleepiness on duty is a frequent and dangerous occurrence. The aim of this study was to evaluate sleep and wakefulness periods of subjects whose work schedule was characterized by an alternation of 2 hours of activity and 4 hours of rest (sleep allowed), repeated 4 times throughout the 24-hr day. This schedule was alternated with 24 hours off duty. Nine healthy male volunteers were monitored by means of ambulatory polysomnography while attending their 24-hr rest-activity schedule. Sleep periods were visually scored according to standard criteria. Wake periods were visually scored using both 30 s and 5 s epochs in order to reveal episodes of drowsiness and/or microsleep. Results showed that total sleep time was substantially reduced as compared to the usual 7-8 hour monophasic nocturnal sleep. Subjects did not sleep during the first rest period (11.00-15.00). Time in sleep linearly increased in the course of the 3 remaining rest periods. Normal sleep stage distribution was substantially spared only in the last rest period (3.00-7.00 a.m.). With regard to duty periods, only a few microsleeps were detected and their number did not significantly vary across the four 2-hr activity periods. In conclusion, this rest-activity schedule, despite the considerable sleep reduction, allowed maintaining good levels of vigilance as shown by the virtual absence of EEG microsleeps. Whether future research will prove that this regimen does not cause an impairment of performance, it should be a suitable strategy for the management of continuous operations.

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

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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.

Effects of menstrual cycle phase and oral contraceptives on alertness, cognitive performance, and circadian rhythms during sleep deprivation

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Wright, K. P. Jr; Badia, P.; Czeisler, C. A. (Principal Investigator)

1999-01-01

The influence of menstrual cycle phase and oral contraceptive use on neurobehavioral function and circadian rhythms were studied in healthy young women (n = 25) using a modified constant routine procedure during 24 h of sleep deprivation. Alertness and performance worsened across sleep deprivation and also varied with circadian phase. Entrained circadian rhythms of melatonin and body temperature were evident in women regardless of menstrual phase or oral contraceptive use. No significant difference in melatonin levels, duration, or phase was observed between women in the luteal and follicular phases, whereas oral contraceptives appeared to increase melatonin levels. Temperature levels were higher in the luteal phase and in oral contraceptive users compared to women in the follicular phase. Alertness on the maintenance of wakefulness test and some tests of cognitive performance were poorest for women in the follicular phase especially near the circadian trough of body temperature. These observations suggest that hormonal changes associated with the menstrual cycle and the use of oral contraceptives contribute to changes in nighttime waking neurobehavioral function and temperature level whereas these factors do not appear to affect circadian phase.

Involvement of autonomic nervous activity changes in gastroesophageal reflux in neonates during sleep and wakefulness.

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Djamal-Dine Djeddi

Full Text Available BACKGROUND: It has been suggested that disturbed activity of the autonomic nervous system is one of the factors involved in gastroesophageal reflux (GER in adults. We sought to establish whether transient ANS dysfunction (as assessed by heart rate variability is associated with the occurrence of GER events in neonates during sleep and wakefulness. METHODS: Nineteen neonates with suspected GER underwent simultaneous, synchronized 12-hour polysomnography and esophageal multichannel impedance-pH monitoring. We compared changes in HRV parameters during three types of periods (control and prior to and during reflux with respect to the vigilance state. RESULTS: The vigilance state influenced the distribution of GER events (P<0.001, with 53.4% observed during wakefulness, 37.6% observed during active sleep and only 9% observed during quiet sleep. A significant increase in the sympathovagal ratio (+32%, P=0.013 was observed in the period immediately prior to reflux (due to a 15% reduction in parasympathetic activity (P=0.017, relative to the control period. This phenomenon was observed during both wakefulness and active sleep. CONCLUSION: Our results showed that GER events were preceded by a vigilance-state-independent decrease in parasympathetic tone. This suggests that a pre-reflux change in ANS activity is one of the factors contributing to the mechanism of reflux in neonates.

[Pharmacological approach to desychronization of the sleep-wakefulness cycle in the military and sport environment].

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Lagarde, D

2007-07-01

Sports and military environments have many common features - intense physical activity, rigorous physical environment (heat, cold, high or low pressure, hypoxia, acceleration...), specific psychosocial atmosphere, team spirit. If combined with jet lag syndrome, these specific conditions can favor altered physical and mental performance. There is always the temptation to use drugs as a simple way to reduce the penalizing effects. The available compounds known to affect sleep and wakefulness include hypnotics, benzodiazepines and non benzodiazepines such as temazepam, zolopidem, and zopiclone, stimulants such as amphetamine and amphetamine-like agents, adrafinil, modafinil, caffeine and chronobiotics substances such as melatonin and, more recently, slow release caffeine. In the sports area, all of these substances except caffeine are on the list of forbidden products, although special authorizations linked to known disease conditions are allowed. In the military setting, the environment may be similar, but the context of use is very different. In the context of a rescue mission, the current practice in the French military organization is to place modafinil pills in the ejection seat of fight planes and in rescue boats. A second context is the use of anti-sleep agents under orders; the debate continues on this and the appropriate recommendations in this context. Self-medication is a third condition, in which case no rules have been defined.

Sleep/wake scheduling scheme for minimizing end-to-end delay in multi-hop wireless sensor networks

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Madani Sajjad

2011-01-01

Full Text Available Abstract We present a sleep/wake schedule protocol for minimizing end-to-end delay for event driven multi-hop wireless sensor networks. In contrast to generic sleep/wake scheduling schemes, our proposed algorithm performs scheduling that is dependent on traffic loads. Nodes adapt their sleep/wake schedule based on traffic loads in response to three important factors, (a the distance of the node from the sink node, (b the importance of the node's location from connectivity's perspective, and (c if the node is in the proximity where an event occurs. Using these heuristics, the proposed scheme reduces end-to-end delay and maximizes the throughput by minimizing the congestion at nodes having heavy traffic load. Simulations are carried out to evaluate the performance of the proposed protocol, by comparing its performance with S-MAC and Anycast protocols. Simulation results demonstrate that the proposed protocol has significantly reduced the end-to-end delay, as well as has improved the other QoS parameters, like average energy per packet, average delay, packet loss ratio, throughput, and coverage lifetime.

Serotonergic-postsynaptic receptors modulate gripping-induced immobility episodes in male taiep rats.

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Eguibar, José R; Cortés, M C; Ita, M L

2009-09-01

The Taiep rat is a myelin mutant with a motor syndrome characterized by tremor, ataxia, immobility, epilepsy, and paralysis. The rat shows a hypomyelination followed by a progressive demyelination. During immobilities taiep rats show a REM-like sleep pattern and a disorganized sleep-wake pattern suggesting taiep rats as a model of narcolepsy-cataplexy. Our study analyzed the role of postsynaptic serotonin receptors in the expression of gripping-induced immobility episodes (IEs) in 8-month-old male taiep rats. The specific postsynaptic serotonin agonist +/-1-(2,5-dimethoxy-4-iodoamphetamine hydrochloride (+/-DOI) decreased the frequency of gripping-induced IEs, but that was not the case with alpha-methyl-serotonin maleate (alpha-methyl-5HT), a nonspecific postsynaptic agonist. Although the serotonin antagonists, ketanserine and metergoline, produced a biphasic effect, first a decrease followed by an increase with higher doses, similar effects were obtained with a mean duration of gripping-induced IEs. These findings correlate with the pharmacological observations in narcoleptic dogs and humans in which serotonin-reuptake inhibitors improve cataplexy, particularly in long-term treatment that could change the serotonin receptor levels. Polysomnographic recordings showed an increase in the awakening time and a decrease in the slow wave and rapid eye movement sleep concomitant with a decrease in immobilities after use of +/-DOI, this being stronger with the highest dose. Taken together, our results show that postsynaptic serotonin receptors are involved in the modulation in gripping-induced IEs caused by the changes in the organization of the sleep-wake cycle in taiep rats. It is possible that specific agonists, without side effects, could be a useful treatment in human narcoleptic patients. 2009 Wiley-Liss, Inc.

The role of sleep and sleep disorders in the development, diagnosis, and management of neurocognitive disorders.

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Michelle A Miller

2015-01-01

It is becoming increasingly apparent that sleep plays an important role in the maintenance, disease prevention, repair and restoration of both mind and body. The sleep and wake cycles are controlled by the pacemaker activity of the superchiasmic nucleus in the hypothalamus but can be disrupted by diseases of the nervous system causing disordered sleep. A lack of sleep has been associated with an increase in all–cause mortality. Likewise, sleep disturbances and sleep disorders may disrupt neu...

Neuro-behavioral pattern of sleep bruxism in wakefulness

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Marila Rezende Azevedo

2018-02-01

Full Text Available AbstractIntroduction: Sleep Bruxism (SB is a non-functional rhythmic movement of the mandible with multifactorial aetiology and complex diagnose. It has been the subject of various studies over the past decades and it is considered a result of actions of the Central Nervous System modulated by Autonomous Nervous System. In this work, we test the hypothesis that SB subjects present a typical and defined neurobehavioral pattern that can be distinct from that of non-bruxers subjects and can be measured during wakefulness. Methods Fifteen sleep bruxers (experimental-group EG and fifteen non-bruxers (control-group CG took part in the experiments. To verify the presence and severity of SB, clinical examinations, anamneses and questionnaires, including Visual Analogic Scale - faces (VAS-f and State-Trait Anxiety Inventory (STAI were applied. To legitimate the diagnoses of SB, a disposable instrument (Bitestrip® to assess the masseter activity during sleep was employed. All subjects were submitted to a set of experiments for measuring various visual evoked responses during the presentation of visual stimuli (pleasant, unpleasant and neutral images. Events in Visual Evoked Potential (VEP were used to compare the neural responses of both CG and EG. Results VAS-f showed EG with higher perception of stress than CG (trait: p=0.05, and lower quality of life for (state: p=0.007. STAI I and II showed significant differences of anxiety between CG and EG (p=0.013 and p=0.004, respectively, being EG the highest. The EG Bitestrip scores confirmed that 100% of subjects were sleep bruxers. Significant differences were found between EG and CG for events associated with emotional (pleasant and unpleasant images in the first 250 ms after stimulation. In general, EG subjects showed higher amplitude and shorter latency of VEP events. Conclusion It is possible to distinguish between SB and non-bruxers subjects during wakefulness, based on differences in amplitude and

cGMP-dependent protein kinase type I is implicated in the regulation of the timing and quality of sleep and wakefulness.

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Sonja Langmesser

Full Text Available Many effects of nitric oxide (NO are mediated by the activation of guanylyl cyclases and subsequent production of the second messenger cyclic guanosine-3',5'-monophosphate (cGMP. cGMP activates cGMP-dependent protein kinases (PRKGs, which can therefore be considered downstream effectors of NO signaling. Since NO is thought to be involved in the regulation of both sleep and circadian rhythms, we analyzed these two processes in mice deficient for cGMP-dependent protein kinase type I (PRKG1 in the brain. Prkg1 mutant mice showed a strikingly altered distribution of sleep and wakefulness over the 24 hours of a day as well as reductions in rapid-eye-movement sleep (REMS duration and in non-REM sleep (NREMS consolidation, and their ability to sustain waking episodes was compromised. Furthermore, they displayed a drastic decrease in electroencephalogram (EEG power in the delta frequency range (1-4 Hz under baseline conditions, which could be normalized after sleep deprivation. In line with the re-distribution of sleep and wakefulness, the analysis of wheel-running and drinking activity revealed more rest bouts during the activity phase and a higher percentage of daytime activity in mutant animals. No changes were observed in internal period length and phase-shifting properties of the circadian clock while chi-squared periodogram amplitude was significantly reduced, hinting at a less robust oscillator. These results indicate that PRKG1 might be involved in the stabilization and output strength of the circadian oscillator in mice. Moreover, PRKG1 deficiency results in an aberrant pattern, and consequently a reduced quality, of sleep and wakefulness, possibly due to a decreased wake-promoting output of the circadian system impinging upon sleep.

Acute toxicity and sleep-wake EEG analysis of Stachtarpheta ...

African Journals Online (AJOL)

The effect of systemic administration of TASC on sleep architecture in rats was also evaluated in Sprague-Dawley rats that were chronically implanted with electrodes for electroencephalogram (EEG) and electromyogram (EMG) recording. The acute toxicity test revealed no lethal effect with doses of SCCR (up to 2000 ...

Metabolic signals in sleep regulation: recent insights

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Shukla C

2016-01-01

Full Text Available Charu Shukla, Radhika Basheer Department of Psychiatry, VA Boston Healthcare System, Harvard Medical School, West Roxbury, MA, USA Abstract: Sleep and energy balance are essential for health. The two processes act in concert to regulate central and peripheral homeostasis. During sleep, energy is conserved due to suspended activity, movement, and sensory responses, and is redirected to restore and replenish proteins and their assemblies into cellular structures. During wakefulness, various energy-demanding activities lead to hunger. Thus, hunger promotes arousal, and subsequent feeding, followed by satiety that promotes sleep via changes in neuroendocrine or neuropeptide signals. These signals overlap with circuits of sleep-wakefulness, feeding, and energy expenditure. Here, we will briefly review the literature that describes the interplay between the circadian system, sleep-wake, and feeding-fasting cycles that are needed to maintain energy balance and a healthy metabolic profile. In doing so, we describe the neuroendocrine, hormonal/peptide signals that integrate sleep and feeding behavior with energy metabolism. Keywords: sleep, energy balance, hypothalamus, metabolism, homeostasis

Chronic sleep restriction induces long-lasting changes in adenosine and noradrenaline receptor density in the rat brain.

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Kim, Youngsoo; Elmenhorst, David; Weisshaupt, Angela; Wedekind, Franziska; Kroll, Tina; McCarley, Robert W; Strecker, Robert E; Bauer, Andreas

2015-10-01

Although chronic sleep restriction frequently produces long-lasting behavioural and physiological impairments in humans, the underlying neural mechanisms are unknown. Here we used a rat model of chronic sleep restriction to investigate the role of brain adenosine and noradrenaline systems, known to regulate sleep and wakefulness, respectively. The density of adenosine A1 and A2a receptors and β-adrenergic receptors before, during and following 5 days of sleep restriction was assessed with autoradiography. Rats (n = 48) were sleep-deprived for 18 h day(-1) for 5 consecutive days (SR1-SR5), followed by 3 unrestricted recovery sleep days (R1-R3). Brains were collected at the beginning of the light period, which was immediately after the end of sleep deprivation on sleep restriction days. Chronic sleep restriction increased adenosine A1 receptor density significantly in nine of the 13 brain areas analysed with elevations also observed on R3 (+18 to +32%). In contrast, chronic sleep restriction reduced adenosine A2a receptor density significantly in one of the three brain areas analysed (olfactory tubercle which declined 26-31% from SR1 to R1). A decrease in β-adrenergic receptors density was seen in substantia innominata and ventral pallidum which remained reduced on R3, but no changes were found in the anterior cingulate cortex. These data suggest that chronic sleep restriction can induce long-term changes in the brain adenosine and noradrenaline receptors, which may underlie the long-lasting neurocognitive impairments observed in chronic sleep restriction. © 2015 European Sleep Research Society.

Circadian Rhythm Sleep Disorders

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Erhan Akinci

2016-06-01

Full Text Available The circadian rhythm sleep disorders define the clinical conditions where sleep and ndash;wake rhythm is disrupted despite optimum environmental and social conditions. They occur as a result of the changes in endogenous circadian hours or non-compatibility of environmental factors or social life with endogenous circadian rhythm. The sleep and ndash;wake rhythm is disrupted continuously or in repeating phases depending on lack of balance between internal and external cycles. This condition leads to functional impairments which cause insomnia, excessive sleepiness or both in people. Application of detailed sleep anamnesis and sleep diary with actigraphy record, if possible, will be sufficient for diagnosis. The treatment aims to align endogenous circadian rhythm with environmental conditions. The purpose of this article is to review pathology, clinical characteristics, diagnosis and treatment of circadian rhythm disorder. [Psikiyatride Guncel Yaklasimlar - Current Approaches in Psychiatry 2016; 8(2: 178-189

Evidence for age-associated disinhibition of the wake drive provided by scoring principal components of the resting EEG spectrum in sleep-provoking conditions.

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Putilov, Arcady A; Donskaya, Olga G

2016-01-01

Age-associated changes in different bandwidths of the human electroencephalographic (EEG) spectrum are well documented, but their functional significance is poorly understood. This spectrum seems to represent summation of simultaneous influences of several sleep-wake regulatory processes. Scoring of its orthogonal (uncorrelated) principal components can help in separation of the brain signatures of these processes. In particular, the opposite age-associated changes were documented for scores on the two largest (1st and 2nd) principal components of the sleep EEG spectrum. A decrease of the first score and an increase of the second score can reflect, respectively, the weakening of the sleep drive and disinhibition of the opposing wake drive with age. In order to support the suggestion of age-associated disinhibition of the wake drive from the antagonistic influence of the sleep drive, we analyzed principal component scores of the resting EEG spectra obtained in sleep deprivation experiments with 81 healthy young adults aged between 19 and 26 and 40 healthy older adults aged between 45 and 66 years. At the second day of the sleep deprivation experiments, frontal scores on the 1st principal component of the EEG spectrum demonstrated an age-associated reduction of response to eyes closed relaxation. Scores on the 2nd principal component were either initially increased during wakefulness or less responsive to such sleep-provoking conditions (frontal and occipital scores, respectively). These results are in line with the suggestion of disinhibition of the wake drive with age. They provide an explanation of why older adults are less vulnerable to sleep deprivation than young adults.

Olfactory Bulb Field Potentials and Respiration in Sleep-Wake States of Mice.

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Jessberger, Jakob; Zhong, Weiwei; Brankačk, Jurij; Draguhn, Andreas

2016-01-01

It is well established that local field potentials (LFP) in the rodent olfactory bulb (OB) follow respiration. This respiration-related rhythm (RR) in OB depends on nasal air flow, indicating that it is conveyed by sensory inputs from the nasal epithelium. Recently RR was found outside the olfactory system, suggesting that it plays a role in organizing distributed network activity. It is therefore important to measure RR and to delineate it from endogenous electrical rhythms like theta which cover similar frequency bands in small rodents. In order to validate such measurements in freely behaving mice, we compared rhythmic LFP in the OB with two respiration-related biophysical parameters: whole-body plethysmography (PG) and nasal temperature (thermocouple; TC). During waking, all three signals reflected respiration with similar reliability. Peak power of RR in OB decreased with increasing respiration rate whereas power of PG increased. During NREM sleep, respiration-related TC signals disappeared and large amplitude slow waves frequently concealed RR in OB. In this situation, PG provided a reliable signal while breathing-related rhythms in TC and OB returned only during microarousals. In summary, local field potentials in the olfactory bulb do reliably reflect respiratory rhythm during wakefulness and REM sleep but not during NREM sleep.

Olfactory Bulb Field Potentials and Respiration in Sleep-Wake States of Mice

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Jakob Jessberger

2016-01-01

Full Text Available It is well established that local field potentials (LFP in the rodent olfactory bulb (OB follow respiration. This respiration-related rhythm (RR in OB depends on nasal air flow, indicating that it is conveyed by sensory inputs from the nasal epithelium. Recently RR was found outside the olfactory system, suggesting that it plays a role in organizing distributed network activity. It is therefore important to measure RR and to delineate it from endogenous electrical rhythms like theta which cover similar frequency bands in small rodents. In order to validate such measurements in freely behaving mice, we compared rhythmic LFP in the OB with two respiration-related biophysical parameters: whole-body plethysmography (PG and nasal temperature (thermocouple; TC. During waking, all three signals reflected respiration with similar reliability. Peak power of RR in OB decreased with increasing respiration rate whereas power of PG increased. During NREM sleep, respiration-related TC signals disappeared and large amplitude slow waves frequently concealed RR in OB. In this situation, PG provided a reliable signal while breathing-related rhythms in TC and OB returned only during microarousals. In summary, local field potentials in the olfactory bulb do reliably reflect respiratory rhythm during wakefulness and REM sleep but not during NREM sleep.

Are endogenous sex hormones related to DNA damage in paradoxically sleep-deprived female rats?

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Andersen, Monica L; Ribeiro, Daniel A; Alvarenga, Tathiana A; Silva, Andressa; Araujo, Paula; Zager, Adriano; Tenorio, Neuli M; Tufik, Sergio

2010-02-01

The aim of this investigation was to evaluate overall DNA damage induced by experimental paradoxical sleep deprivation (PSD) in estrous-cycling and ovariectomized female rats to examine possible hormonal involvement during DNA damage. Intact rats in different phases of the estrous cycle (proestrus, estrus, and diestrus) or ovariectomized female Wistar rats were subjected to PSD by the single platform technique for 96 h or were maintained for the equivalent period as controls in home-cages. After this period, peripheral blood and tissues (brain, liver, and heart) were collected to evaluate genetic damage using the single cell gel (comet) assay. The results showed that PSD caused extensive genotoxic effects in brain cells, as evident by increased DNA migration rates in rats exposed to PSD for 96 h when compared to negative control. This was observed for all phases of the estrous cycle indistinctly. In ovariectomized rats, PSD also led to DNA damage in brain cells. No significant statistically differences were detected in peripheral blood, the liver or heart for all groups analyzed. In conclusion, our data are consistent with the notion that genetic damage in the form of DNA breakage in brain cells induced by sleep deprivation overrides the effects related to endogenous female sex hormones. Copyright 2009 Elsevier Inc. 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; 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.

Sleep habits in adolescents of Saudi Arabia; distinct patterns and extreme sleep schedules.

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Merdad, Roah A; Merdad, Leena A; Nassif, Rawan A; El-Derwi, Douaa; Wali, Siraj O

2014-11-01

There is a need for comprehensive studies on adolescents' sleep habits in the Middle Eastern region. The aim of this study was to investigate the sleep-wake patterns, prevalence of excessive daytime sleepiness (EDS), and disturbed sleep among adolescents in Saudi Arabia and to identify the associated factors. The study was a cross-sectional survey done on a random sample of 1035 high school students, ages 14-23 years, in Jeddah, Saudi Arabia. The response rate was 91%. Students filled a self-reported questionnaire that included sleep-wake questions, Pittsburgh Sleep Quality Index, Epworth Sleepiness Scale, Perceived Stress Scale, academic performance, and personal data. Students slept an average of 7.0 hours on school nights, with an average delay of 2.8 and 6.0 hours in weekend sleep and rise times, respectively. Around 1 in 10 students stayed up all night and slept after returning from school (exhibiting a reversed sleep cycle) on weeknights. This pattern was more prevalent among boys and students with lower grade point averages. The prevalence of sleep disturbance was 65%, and EDS was found in 37% of the students. Predictors of EDS were school type, stress, napping and caffeine use, while gender was a predictor of disturbed sleep. Adolescents in Saudi Arabia showed a high percentage of poor sleep quality. Compared with adolescents from other countries, they had a larger delay in weekend sleep and rise times. An alarming reversed sleep cycle on weekdays is present and highlights the need for further assessment. Copyright © 2014 Elsevier B.V. All rights reserved.

Salivary melatonin levels and sleep-wake rhythms in pregnant women with hypertensive and glucose metabolic disorders: A prospective analysis.

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Shimada, Mieko; Seki, Hiroyuki; Samejima, Michikazu; Hayase, Mako; Shirai, Fumie

2016-02-01

In preeclampsia and gestational diabetes, the sympathetic nerves are activated, leading to disrupted sleep. Melatonin, which transmits information to regulate the sleep-wake rhythm and other such biorhythms, has been implicated in insulin resistance, antioxidant behaviors, and metabolic syndrome. In addition, its reduced secretion increases the risk of hypertension and diabetes. The aim of this study was to elucidate the features of melatonin secretion, sleep quality, and sleep-wake rhythms in pregnant women with complications. Fifty-eight pregnant women with pregnancy complications (hypertensive or glucose metabolic disorders) and 40 healthy pregnant women completed questionnaires, including sleep logs and the Pittsburgh Sleep Quality Index (PSQI), during the second to third trimesters. Their salivary melatonin levels were also measured. Pregnant women with complications had significantly lower morning (p melatonin values than healthy pregnant women. Pregnant women with complications also had significantly smaller melatonin amplitudes than healthy pregnant women (p melatonin secretion, and their values were lower throughout the day than healthy pregnant women.

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-wake patterns and their influence on school performance in Portuguese adolescents.

Science.gov (United States)

Duarte, João; Nelas, Paula; Chaves, Cláudia; Ferreira, Manuela; Coutinho, Emília; Cunha, Madalena

2014-11-01

To characterise sleep-wake patterns and their influence on academic performance for a sample of Portuguese adolescents. Cross-sectional, analytical-explanatory, correlational epidemiological research. The protocol includes the composite morningness questionnaire (Barton et al, 1985 adapted by Silva et al, 1985), the Epworth Sleepiness Scale (Murray, 1991), chronic fatigue scale (Smith et al, 1995), the Pittsburgh Sleep Quality Index (Buysse, 1988), Educational Achievement (Fermin, 2005), personal and academic data. 2094 students (55.3% girls; 16-23 years old; M=16.82±1.25) attending secondary school in central Portugal. Living in urban areas, living with their parents and about 57.1% are in a family with reasonable economic resources. Adolescents' sleep patterns reveal that they sleep on average between 8-9 hours a night, do not use medication to sleep, with sleep latency within the normal range, with good sleep efficiency, without daytime dysfunction and with undisturbed sleep, predominantly intermediate chronotype. Minor drowsiness, increased sleep efficiency, improved subjective sleep satisfaction, less sleep disturbance, less daytime dysfunction, not consuming hypnotic medications, associated with better academic performance. Morningness/eveningness, sleep efficiency, daytime dysfunction and sleep latency emerge as predictors of academic performance. The chronotype interacts to predict the quality of sleep enhancing it as a mediator of school performance. Sleep and associated individual characteristics should be considered in the diagnosis and intervention process in secondary education. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

Parkinsonian syndromes presenting with circadian rhythm sleep disorder- advanced sleep-phase type.

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Shukla, Garima; Kaul, Bhavna; Gupta, Anupama; Goyal, Vinay; Behari, Madhuri

2015-01-01

Circadian rhythm sleep disorder-advanced sleep-phase type is a relatively uncommon disorder, mostly seen among the elderly population. Impaired circadian rhythms have been reported in neurodegenerative conditions; however, there are no reports of any circadian rhythm sleep disorder among patients with Parkinsonian syndromes. We report two patients who presented with this circadian rhythm disorder, and were then diagnosed with a Parkinsonian syndrome. The cases. A 65-year-old retired man presented with history of abrupt change in sleep schedules, sleeping around 6.30-7 p.m. and waking up around 3-4 a.m. for the last 2 months. On detailed examination, the patient was observed to have symmetrical bradykinesia and cogwheel rigidity of limbs. A diagnosis of multiple system atrophy was made, supported by MRI findings and evidence of autonomic dysfunction. Symptoms of change in sleep-wake cycles resolved over the next 1 year, while the patient was treated with dopaminergic therapy. A 47-year-old man, who was being evaluated for presurgical investigation for refractory temporal lobe epilepsy, presented with complaints suggestive of dysarthria, bradykinesia of limbs and frequent falls for 5 months. Simultaneously, he began to sleep around 7 p.m. and wake up at about 2-3 a.m. Examination revealed severe axial rigidity, restricted vertical gaze and bradykinesia of limbs. A diagnosis of progressive supranuclear palsy was made. This is the first report of Parkinson's plus syndromes presenting with a circadian rhythm sleep disorder-advanced sleep-phase type. More prospective assessment for circadian sleep disorders may introduce useful insights into similar associations. Copyright 2015, NMJI.

Cell Injury and Repair Resulting from Sleep Loss and Sleep Recovery in Laboratory Rats

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Everson, Carol A.; Henchen, Christopher J.; Szabo, Aniko; Hogg, Neil

2014-01-01

Study Objectives: Increased cell injury would provide the type of change in constitution that would underlie sleep disruption as a risk factor for multiple diseases. The current study was undertaken to investigate cell injury and altered cell fate as consequences of sleep deprivation, which were predicted from systemic clues. Design: Partial (35% sleep reduction) and total sleep deprivation were produced in rats for 10 days, which was tolerated and without overtly deteriorated health. Recovery rats were similarly sleep deprived for 10 days, then allowed undisturbed sleep for 2 days. The plasma, liver, lung, intestine, heart, and spleen were analyzed and compared to control values for damage to DNA, proteins, and lipids; apoptotic cell signaling and death; cell proliferation; and concentrations of glutathione peroxidase and catalase. Measurements and Results: Oxidative DNA damage in totally sleep deprived rats was 139% of control values, with organ-specific effects in the liver (247%), lung (166%), and small intestine (145%). Overall and organ-specific DNA damage was also increased in partially sleep deprived rats. In the intestinal epithelium, total sleep deprivation resulted in 5.3-fold increases in dying cells and 1.5-fold increases in proliferating cells, compared with control. Two days of recovery sleep restored the balance between DNA damage and repair, and resulted in normal or below-normal metabolic burdens and oxidative damage. Conclusions: These findings provide physical evidence that sleep loss causes cell damage, and in a manner expected to predispose to replication errors and metabolic abnormalities; thereby providing linkage between sleep loss and disease risk observed in epidemiological findings. Properties of recovery sleep include biochemical and molecular events that restore balance and decrease cell injury. Citation: Everson CA, Henchen CJ, Szabo A, Hogg N. Cell injury and repair resulting from sleep loss and sleep recovery in laboratory rats

Caffeine, sleep and wakefulness: implications of new understanding about withdrawal reversal.

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James, Jack E; Keane, Michael A

2007-12-01

The broad aim of this review is to critically examine the implications of new understanding concerning caffeine withdrawal and withdrawal reversal in the context of research concerned with the effects of caffeine on sleep and wakefulness. A comprehensive search was conducted for relevant experimental studies in the PubMED and PsycINFO databases. Studies were assessed with particular reference to methodological adequacy for controlling against confounding due to caffeine withdrawal and withdrawal reversal. This assessment was used to clarify evidence of effects, highlight areas of ambiguity and derive recommendations for future research. It was found that researchers have generally failed to take account of the fact that habitual use of caffeine, even at moderate levels, leads to physical dependence evidenced by physiological, behavioural and subjective withdrawal effects during periods of abstinence. Consequently, there has been near-complete absence of adequate methodological controls against confounding due to reversal of withdrawal effects when caffeine is experimentally administered. The findings of what has been a substantial research effort to elucidate the effects of caffeine on sleep and wakefulness, undertaken over a period spanning decades, are ambiguous. Current shortcomings can be redressed by incorporating suitable controls in new experimental designs.

The Sleeping Cerebellum.

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Canto, Cathrin B; Onuki, Yoshiyuki; Bruinsma, Bastiaan; van der Werf, Ysbrand D; De Zeeuw, Chris I

2017-05-01

We sleep almost one-third of our lives and sleep plays an important role in critical brain functions like memory formation and consolidation. The role of sleep in cerebellar processing, however, constitutes an enigma in the field of neuroscience; we know little about cerebellar sleep-physiology, cerebro-cerebellar interactions during sleep, or the contributions of sleep to cerebellum-dependent memory consolidation. Likewise, we do not understand why cerebellar malfunction can lead to changes in the sleep-wake cycle and sleep disorders. In this review, we evaluate how sleep and cerebellar processing may influence one another and highlight which scientific routes and technical approaches could be taken to uncover the mechanisms underlying these interactions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Circadian clocks, rhythmic synaptic plasticity and the sleep-wake cycle in zebrafish.

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Elbaz, Idan; Foulkes, Nicholas S; Gothilf, Yoav; Appelbaum, Lior

2013-01-01

The circadian clock and homeostatic processes are fundamental mechanisms that regulate sleep. Surprisingly, despite decades of research, we still do not know why we sleep. Intriguing hypotheses suggest that sleep regulates synaptic plasticity and consequently has a beneficial role in learning and memory. However, direct evidence is still limited and the molecular regulatory mechanisms remain unclear. The zebrafish provides a powerful vertebrate model system that enables simple genetic manipulation, imaging of neuronal circuits and synapses in living animals, and the monitoring of behavioral performance during day and night. Thus, the zebrafish has become an attractive model to study circadian and homeostatic processes that regulate sleep. Zebrafish clock- and sleep-related genes have been cloned, neuronal circuits that exhibit circadian rhythms of activity and synaptic plasticity have been studied, and rhythmic behavioral outputs have been characterized. Integration of this data could lead to a better understanding of sleep regulation. Here, we review the progress of circadian clock and sleep studies in zebrafish with special emphasis on the genetic and neuroendocrine mechanisms that regulate rhythms of melatonin secretion, structural synaptic plasticity, locomotor activity and sleep.

Endoplasmic reticulum stress in wake-active neurons progresses with aging.

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Naidoo, Nirinjini; Zhu, Jingxu; Zhu, Yan; Fenik, Polina; Lian, Jie; Galante, Ray; Veasey, Sigrid

2011-08-01

Fragmentation of wakefulness and sleep are expected outcomes of advanced aging. We hypothesize that wake neurons develop endoplasmic reticulum dyshomeostasis with aging, in parallel with impaired wakefulness. In this series of experiments, we sought to more fully characterize age-related changes in wakefulness and then, in relevant wake neuronal populations, explore functionality and endoplasmic reticulum homeostasis. We report that old mice show greater sleep/wake transitions in the active period with markedly shortened wake periods, shortened latencies to sleep, and less wake time in the subjective day in response to a novel social encounter. Consistent with sleep/wake instability and reduced social encounter wakefulness, orexinergic and noradrenergic wake neurons in aged mice show reduced c-fos response to wakefulness and endoplasmic reticulum dyshomeostasis with increased nuclear translocation of CHOP and GADD34. We have identified an age-related unfolded protein response injury to and dysfunction of wake neurons. It is anticipated that these changes contribute to sleep/wake fragmentation and cognitive impairment in aging. © 2011 The Authors. Aging Cell © 2011 Blackwell Publishing Ltd/Anatomical Society of Great Britain and Ireland.

What the cerveau isolé preparation tells us nowadays about sleep-wake mechanisms?

Science.gov (United States)

Gottesmann, C

1988-01-01

The intercollicular transected preparation opened a rich field for investigations of sleep-wake mechanisms. Initial results showed that brain stem ascending influences are essential for maintaining an activated cortex. It was subsequently shown that the forebrain also develops activating influences, since EEG desynchronization of the cortex reappears in the chronic cerveau isolé preparation, and continuous or almost continuous theta rhythm is able to occur in the acute cerveau isolé preparation. A brief "intermediate stage" of sleep occurs during natural sleep just prior to and after paradoxical sleep. It is characterized by cortical spindle bursts, hippocampal low frequency theta activity (two patterns of the acute cerveau isolé preparation) and is accompanied by a very low thalamic transmission level, suggesting a cerveau isolé-like state. The chronic cerveau isolé preparation also demonstrates that the executive processes of paradoxical sleep are located in the lower brain stem, while the occurrence of this sleep stage seems to be modulated by forebrain structures.

Locus Coeruleus and Tuberomammillary Nuclei Ablations Attenuate Hypocretin/Orexin Antagonist-Mediated REM Sleep.

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Schwartz, Michael D; Nguyen, Alexander T; Warrier, Deepti R; Palmerston, Jeremiah B; Thomas, Alexia M; Morairty, Stephen R; Neylan, Thomas C; Kilduff, Thomas S

2016-01-01

Hypocretin 1 and 2 (Hcrts; also known as orexin A and B), excitatory neuropeptides synthesized in cells located in the tuberal hypothalamus, play a central role in the control of arousal. Hcrt inputs to the locus coeruleus norepinephrine (LC NE) system and the posterior hypothalamic histaminergic tuberomammillary nuclei (TMN HA) are important efferent pathways for Hcrt-induced wakefulness. The LC expresses Hcrt receptor 1 (HcrtR1), whereas HcrtR2 is found in the TMN. Although the dual Hcrt/orexin receptor antagonist almorexant (ALM) decreases wakefulness and increases NREM and REM sleep time, the neural circuitry that mediates these effects is currently unknown. To test the hypothesis that ALM induces sleep by selectively disfacilitating subcortical wake-promoting populations, we ablated LC NE neurons (LCx) or TMN HA neurons (TMNx) in rats using cell-type-specific saporin conjugates and evaluated sleep/wake following treatment with ALM and the GABAA receptor modulator zolpidem (ZOL). Both LCx and TMNx attenuated the promotion of REM sleep by ALM without affecting ALM-mediated increases in NREM sleep. Thus, eliminating either HcrtR1 signaling in the LC or HcrtR2 signaling in the TMN yields similar effects on ALM-induced REM sleep without affecting NREM sleep time. In contrast, neither lesion altered ZOL efficacy on any measure of sleep-wake regulation. These results contrast with those of a previous study in which ablation of basal forebrain cholinergic neurons attenuated ALM-induced increases in NREM sleep time without affecting REM sleep, indicating that Hcrt neurotransmission influences distinct aspects of NREM and REM sleep at different locations in the sleep-wake regulatory network.

2B-Alert Web: An Open-Access Tool for Predicting the Effects of Sleep/Wake Schedules and Caffeine Consumption on Neurobehavioral Performance.

Science.gov (United States)

Reifman, Jaques; Kumar, Kamal; Wesensten, Nancy J; Tountas, Nikolaos A; Balkin, Thomas J; Ramakrishnan, Sridhar

2016-12-01

Computational tools that predict the effects of daily sleep/wake amounts on neurobehavioral performance are critical components of fatigue management systems, allowing for the identification of periods during which individuals are at increased risk for performance errors. However, none of the existing computational tools is publicly available, and the commercially available tools do not account for the beneficial effects of caffeine on performance, limiting their practical utility. Here, we introduce 2B-Alert Web, an open-access tool for predicting neurobehavioral performance, which accounts for the effects of sleep/wake schedules, time of day, and caffeine consumption, while incorporating the latest scientific findings in sleep restriction, sleep extension, and recovery sleep. We combined our validated Unified Model of Performance and our validated caffeine model to form a single, integrated modeling framework instantiated as a Web-enabled tool. 2B-Alert Web allows users to input daily sleep/wake schedules and caffeine consumption (dosage and time) to obtain group-average predictions of neurobehavioral performance based on psychomotor vigilance tasks. 2B-Alert Web is accessible at: https://2b-alert-web.bhsai.org. The 2B-Alert Web tool allows users to obtain predictions for mean response time, mean reciprocal response time, and number of lapses. The graphing tool allows for simultaneous display of up to seven different sleep/wake and caffeine schedules. The schedules and corresponding predicted outputs can be saved as a Microsoft Excel file; the corresponding plots can be saved as an image file. The schedules and predictions are erased when the user logs off, thereby maintaining privacy and confidentiality. The publicly accessible 2B-Alert Web tool is available for operators, schedulers, and neurobehavioral scientists as well as the general public to determine the impact of any given sleep/wake schedule, caffeine consumption, and time of day on performance of a

Circadian clocks, rhythmic synaptic plasticity and the sleep-wake cycle in zebrafish

Directory of Open Access Journals (Sweden)

Idan eElbaz

2013-02-01

Full Text Available The circadian clock and homeostatic processes are fundamental mechanisms that regulate sleep. Surprisingly, despite decades of research, we still do not know why we sleep. Intriguing hypotheses suggest that sleep regulates synaptic plasticity and consequently has a beneficial role in learning and memory. However, direct evidence is still limited and the molecular regulatory mechanisms remain unclear. The zebrafish provides a powerful vertebrate model system that enables simple genetic manipulation, imaging of neuronal circuits and synapses in living animals, and the monitoring of behavioral performance during day and night. Thus, the zebrafish has become an attractive model to study circadian and homeostatic processes that regulate sleep. Zebrafish clock- and sleep-related genes have been cloned, neuronal circuits that exhibit circadian rhythms of activity and synaptic plasticity have been studied, and rhythmic behavioral outputs have been characterized. Integration of this data could lead to a better understanding of sleep regulation. Here, we review the progress of circadian clock and sleep studies in zebrafish with special emphasis on the genetic and neuroendocrine mechanisms that regulate rhythms of melatonin secretion, structural synaptic plasticity, locomotor activity and sleep.

Seasonal aspects of sleep in the Djungarian hamster

Directory of Open Access Journals (Sweden)

Deboer Tom

2003-05-01

Full Text Available Abstract Background Changes in photoperiod and ambient temperature trigger seasonal adaptations in the physiology and behaviour of many species, including the Djungarian hamster. Exposure of the hamsters to a short photoperiod and low ambient temperature leads to a reduction of the polyphasic distribution of sleep and waking over the light and dark period. In contrast, a long photoperiod enhances the daily sleep-wake amplitude leading to a decline of slow-wave activity in NREM sleep within the light period. It is unknown whether these changes can be attributed specifically to photoperiod and/or ambient temperature, or whether endogenous components are contributing factors. The influence of endogenous factors was investigated by recording sleep in Djungarian hamsters invariably maintained at a low ambient temperature and fully adapted to a short photoperiod. The second recording was performed when they had returned to summer physiology, despite the maintenance of the 'winter' conditions. Results Clear winter-summer differences were seen in sleep distribution, while total sleep time was unchanged. A significantly higher light-dark cycle modulation in NREM sleep, REM sleep and waking was observed in hamsters in the summer physiological state compared to those in the winter state. Moreover, only in summer, REM sleep episodes were longer and waking bouts were shorter during the light period compared to the dark period. EEG power in the slow-wave range (0.75–4.0 Hz in both NREM sleep and REM sleep was higher in animals in the summer physiological state than in those in the 'winter' state. In winter SWA in NREM sleep was evenly distributed over the 24 h, while in summer it decreased during the light period and increased during the dark period. Conclusion Endogenous changes in the organism underlie the differences in sleep-wake redistribution we have observed previously in hamsters recorded in a short and long photoperiod.

SLEEP HABITS AMONG FIRST YEAR MEDICAL STUDENTS

OpenAIRE

Neera; Varun; Yogesh

2016-01-01

Sleep is part of the rhythm of life; without a good sleep the mind is less adaptive, mood is altered and the body loses the ability to refresh. The sleep-wake cycle of medical students is quite different and sleep deprivation, poor sleep quality, occurrence of napping episodes during the day. This study was designed to assess sleep habits in first year medical students. MATERIAL AND METHODS Participants of this study were healthy medical students of first year MBBS course of S...

Orexin receptor antagonist-induced sleep does not impair the ability to wake in response to emotionally salient acoustic stimuli in dogs

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Pamela L. Tannenbaum

2014-05-01

Full Text Available The ability to awaken from sleep in response to important stimuli is a critical feature of normal sleep, as is maintaining sleep continuity in the presence of irrelevant background noise. Dual orexin receptor antagonists (DORAs effectively promote sleep across species by targeting the evolutionarily conserved wake-promoting orexin signaling pathway. This study in dogs investigated whether DORA-induced sleep preserved the ability to awaken appropriately to salient acoustic stimuli but remain asleep when exposed to irrelevant stimuli. Sleep and wake in response to DORAs, vehicle, GABA-A receptor modulators (diazepam, eszopiclone and zolpidem and antihistamine (diphenhydramine administration were evaluated in telemetry-implanted adult dogs with continuous electrocorticogram, electromyogram, electrooculogram, and activity recordings. DORAs induced sleep, but GABA-A modulators and antihistamine induced paradoxical hyperarousal. Thus, salience gating studies were conducted during DORA-22 (0.3, 1, and 5 mg/kg; day and night and vehicle nighttime sleep. The acoustic stimuli were either classically conditioned using food reward and positive attention (salient stimulus or presented randomly (neutral stimulus. Once conditioned, the tones were presented at sleep times corresponding to maximal DORA-22 exposure. In response to the salient stimuli, dogs woke completely from vehicle and orexin-antagonized sleep across all sleep stages but rarely awoke to neutral stimuli. Notably, acute pharmacological antagonism of orexin receptors paired with emotionally salient anticipation produced wake, not cataplexy, in a species where genetic (chronic loss of orexin receptor signaling leads to narcolepsy/cataplexy. DORA-induced sleep in this species thereby retains the desired capacity to awaken to emotionally salient acoustic stimuli while preserving uninterrupted sleep in response to irrelevant stimuli.

Computer Simulation of Noise Effects of the Neighborhood of Stimulus Threshold for a Mathematical Model of Homeostatic Regulation of Sleep-Wake Cycles

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Wuyin Jin

2017-01-01

Full Text Available The noise effects on a homeostatic regulation of sleep-wake cycles’ neuronal mathematical model determined by the hypocretin/orexin and the local glutamate interneurons spatiotemporal behaviors are studied within the neighborhood of stimulus threshold in this work; the neuronal noise added to the stimulus, the conductance, and the activation variable of the modulation function are investigated, respectively, based on a circadian input skewed in sine function. The computer simulation results suggested that the increased amplitude of external current input will lead to the fact that awakening time is advanced but the sleepy time remains the same; for the bigger conductance and modulation noise, the regulatory mechanism of the model sometimes will be collapsed and the coupled two neurons of the model show very irregular activities; the falling asleep or wake transform appears at nondeterminate time.

The Role of ATP in Sleep Regulation

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Sachiko eChikahisa

2011-12-01

Full Text Available One of the functions of sleep is to maintain energy balance in the brain. There are a variety of hypotheses related to how metabolic pathways interact with sleep/wake regulation. A major finding that demonstrates an interaction between sleep and metabolic homeostasis is the involvement of adenosine in sleep homeostasis. An accumulation of adenosine is supplied from ATP, which can act as an energy currency in the cell. Extracellularly, ATP can act as an activity-dependent signaling molecule, especially in regard to communication between neurons and glia, including astrocytes. Furthermore, the intracellular AMP/ATP ratio controls the activity of AMP-activated protein kinase (AMPK, which is a potent energy regulator and is recently reported to play a role in the regulation of sleep homeostasis. Brain ATP may support multiple functions in the regulation of the sleep/wake cycle and sleep homeostasis.

Tasimelteon (Hetlioz™): A New Melatonin Receptor Agonist for the Treatment of Non-24-Hour Sleep-Wake Disorder.

Science.gov (United States)

Bonacci, Janene M; Venci, Jineane V; Gandhi, Mona A

2015-10-01

In January 2014, the US Food and Drug Administration approved tasimelteon (Hetlioz™), a melatonin-receptor agonist for the treatment of non-24-hour sleep-wake disorder. This article provides an overview of the mechanism of action, pharmacokinetic properties, as well as the clinical efficacy, safety, and tolerability of tasimelteon. Relevant information was identified through a comprehensive literature search of several databases using the key words tasimelteon, Non-24-hour Sleep-Wake disorder, Non-24, and melatonin. Further information was obtained from the tasimelteon package insert, fda.gov, clinicaltrials.gov, briefing materials provided by Vanda Pharmaceuticals, and posters from scientific meetings. © The Author(s) 2014.

Altered Sleep Homeostasis in Rev-erbα Knockout Mice.

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Mang, Géraldine M; La Spada, Francesco; Emmenegger, Yann; Chappuis, Sylvie; Ripperger, Jürgen A; Albrecht, Urs; Franken, Paul

2016-03-01

The nuclear receptor REV-ERBα is a potent, constitutive transcriptional repressor critical for the regulation of key circadian and metabolic genes. Recently, REV-ERBα's involvement in learning, neurogenesis, mood, and dopamine turnover was demonstrated suggesting a specific role in central nervous system functioning. We have previously shown that the brain expression of several core clock genes, including Rev-erbα, is modulated by sleep loss. We here test the consequences of a loss of REV-ERBα on the homeostatic regulation of sleep. EEG/EMG signals were recorded in Rev-erbα knockout (KO) mice and their wild type (WT) littermates during baseline, sleep deprivation, and recovery. Cortical gene expression measurements after sleep deprivation were contrasted to baseline. Although baseline sleep/wake duration was remarkably similar, KO mice showed an advance of the sleep/wake distribution relative to the light-dark cycle. After sleep onset in baseline and after sleep deprivation, both EEG delta power (1-4 Hz) and sleep consolidation were reduced in KO mice indicating a slower increase of homeostatic sleep need during wakefulness. This slower increase might relate to the smaller increase in theta and gamma power observed in the waking EEG prior to sleep onset under both conditions. Indeed, the increased theta activity during wakefulness predicted delta power in subsequent NREM sleep. Lack of Rev-erbα increased Bmal1, Npas2, Clock, and Fabp7 expression, confirming the direct regulation of these genes by REV-ERBα also in the brain. Our results add further proof to the notion that clock genes are involved in sleep homeostasis. Because accumulating evidence directly links REV-ERBα to dopamine signaling the altered homeostatic regulation of sleep reported here are discussed in that context. © 2016 Associated Professional Sleep Societies, LLC.

Short-term total sleep deprivation alters delay-conditioned memory in the rat.

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Tripathi, Shweta; Jha, Sushil K

2016-06-01

Short-term sleep deprivation soon after training may impair memory consolidation. Also, a particular sleep stage or its components increase after learning some tasks, such as negative and positive reinforcement tasks, avoidance tasks, and spatial learning tasks, and so forth. It suggests that discrete memory types may require specific sleep stage or its components for their optimal processing. The classical conditioning paradigms are widely used to study learning and memory but the role of sleep in a complex conditioned learning is unclear. Here, we have investigated the effects of short-term sleep deprivation on the consolidation of delay-conditioned memory and the changes in sleep architecture after conditioning. Rats were trained for the delay-conditioned task (for conditioning, house-light [conditioned stimulus] was paired with fruit juice [unconditioned stimulus]). Animals were divided into 3 groups: (a) sleep deprived (SD); (b) nonsleep deprived (NSD); and (c) stress control (SC) groups. Two-way ANOVA revealed a significant interaction between groups and days (training and testing) during the conditioned stimulus-unconditioned stimulus presentation. Further, Tukey post hoc comparison revealed that the NSD and SC animals exhibited significant increase in performances during testing. The SD animals, however, performed significantly less during testing. Further, we observed that wakefulness and NREM sleep did not change after training and testing. Interestingly, REM sleep increased significantly on both days compared to baseline more specifically during the initial 4-hr time window after conditioning. Our results suggest that the consolidation of delay-conditioned memory is sleep-dependent and requires augmented REM sleep during an explicit time window soon after training. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

The role of 5-hydroxytryptophan (5-HTP) in the regulation of the sleep/wake cycle in parachlorophenylalanine (p-CPA) pretreated rat: a multiple approach study.

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Touret, M; Sarda, N; Gharib, A; Geffard, M; Jouvet, M

1991-01-01

In the rat, the insomnia which follows the administration of parachlorophenylalanine (p-CPA), a serotonin synthesis inhibitor, is transiently reversed either by intra-cisternal injection of L-5-HTP or by an associated injection of 5-HTP and an L-aromatic-acid-decarboxylase inhibitor (benserazide). Histochemical, immunohistochemical and chemical investigations showed that 5-HTP administration does not lead to a detectable increase in cerebral 5-HT. These findings suggest that the restoration of sleep after p-CPA treatment could be mediated by the central action of 5-HTP.

Neuroethologic differences in sleep deprivation induced by the single- and multiple-platform methods

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R. Medeiros

1998-05-01

Full Text Available It has been proposed that the multiple-platform method (MP for desynchronized sleep (DS deprivation eliminates the stress induced by social isolation and by the restriction of locomotion in the single-platform (SP method. MP, however, induces a higher increase in plasma corticosterone and ACTH levels than SP. Since deprivation is of heuristic value to identify the functional role of this state of sleep, the objective of the present study was to determine the behavioral differences exhibited by rats during sleep deprivation induced by these two methods. All behavioral patterns exhibited by a group of 7 albino male Wistar rats submitted to 4 days of sleep deprivation by the MP method (15 platforms, spaced 150 mm apart and by 7 other rats submitted to sleep deprivation by the SP method were recorded in order to elaborate an ethogram. The behavioral patterns were quantitated in 10 replications by naive observers using other groups of 7 rats each submitted to the same deprivation schedule. Each quantification session lasted 35 min and the behavioral patterns presented by each rat over a period of 5 min were counted. The results obtained were: a rats submitted to the MP method changed platforms at a mean rate of 2.62 ± 1.17 platforms h-1 animal-1; b the number of episodes of noninteractive waking patterns for the MP animals was significantly higher than that for SP animals (1077 vs 768; c additional episodes of waking patterns (26.9 ± 18.9 episodes/session were promoted by social interaction in MP animals; d the cumulative number of sleep episodes observed in the MP test (311 was significantly lower (chi-square test, 1 d.f., P<0.05 than that observed in the SP test (534; e rats submitted to the MP test did not show the well-known increase in ambulatory activity observed after the end of the SP test; f comparison of 6 MP and 6 SP rats showed a significantly shorter latency to the onset of DS in MP rats (7.8 ± 4.3 and 29.0 ± 25.0 min, respectively

Sleep Control Game for Wireless Sensor Networks

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Sang Hoon Lee

2016-01-01

Full Text Available In wireless sensor networks (WSNs, each node controls its sleep to reduce energy consumption without sacrificing message latency. In this paper we apply the game theory, which is a powerful tool that explains how each individual acts for his or her own economic benefit, to analyze the optimal sleep schedule for sensor nodes. We redefine this sleep control game as a modified version of the Prisoner’s Dilemma. In the sleep control game, each node decides whether or not it wakes up for the cycle. Payoff functions of the sleep control game consider the expected traffic volume, network conditions, and the expected packet delay. According to the payoff function, each node selects the best wake-up strategy that may minimize the energy consumption and maintain the latency performance. To investigate the performance of our algorithm, we apply the sleep control game to X-MAC, which is one of the recent WSN MAC protocols. Our detailed packet level simulations confirm that the proposed algorithm can effectively reduce the energy consumption by removing unnecessary wake-up operations without loss of the latency performance.

Sleep and wakefulness in somnambulism: a spectral analysis study.

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Guilleminault, C; Poyares, D; Aftab, F A; Palombini, L; Abat, F

2001-08-01

The sleep structure and the dynamics of EEG slow-wave activity (SWA) were investigated in 12 young adults and age- and gender-matched controls. Polysomnography was performed in subjects with well-documented chronic sleepwalking and in matched controls. Blinded visual scoring was performed using the international criteria from the Rechtschaffen and Kales atlas [A manual of standardized technology, techniques and scoring systems for sleep stages of human subjects. Los Angeles: UCLA Brain Information Service, Brain Research Institute, 1968.] and by determining the presence of microarousals as defined in the American Sleep Disorders Association (ASDA) atlas [Sleep 15 (1992) 173.]. An evaluation of SWA overnight was performed on total nocturnal sleep to determine if a difference existed between groups of subjects, since sleepwalking usually originates with slow-wave sleep. Investigation of the delta power in successive nonoverlapping 4-second windows in the 32 seconds just prior to EMG activity associated with a confusional arousal was also conducted. One central EEG lead was used for all analyses. Somnambulistic individuals experienced more disturbed sleep than controls during the first NREM-REM sleep cycle. They had a higher number of ASDA arousals and presented lower peak of SWA during the first cycle that led to a lower SWA decline overnight. When the investigation focused on the short segment immediately preceding a confusional arousal, they presented an important increase in the relative power of low delta (0.75-2 Hz) just prior to the confusional arousal. Sleepwalkers undergo disturbed nocturnal sleep at the beginning of the night. The increased power of low delta just prior to the confusional arousal experienced may not be related to Stages 3-4 NREM sleep. We hypothesize that it may be translated as a cortical reaction to brain activation.

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

2012-01-01

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 ...

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.

Effects of intrauterine growth restriction on sleep and the cardiovascular system: The use of melatonin as a potential therapy?

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Yiallourou, Stephanie R; Wallace, Euan M; Miller, Suzanne L; Horne, Rosemary S C

2016-04-01

Intrauterine growth restriction (IUGR) complicates 5-10% of pregnancies and is associated with increased risk of preterm birth, mortality and neurodevelopmental delay. The development of sleep and cardiovascular control are closely coupled and IUGR is known to alter this development. In the long-term, IUGR is associated with altered sleep and an increased risk of hypertension in adulthood. Melatonin plays an important role in the sleep-wake cycle. Experimental animal studies have shown that melatonin therapy has neuroprotective and cardioprotective effects in the IUGR fetus. Consequently, clinical trials are currently underway to assess the short and long term effects of antenatal melatonin therapy in IUGR pregnancies. Given melatonin's role in sleep regulation, this hormone could affect the developing infants' sleep-wake cycle and cardiovascular function after birth. In this review, we will 1) examine the role of melatonin as a therapy for IUGR pregnancies and the potential implications on sleep and the cardiovascular system; 2) examine the development of sleep-wake cycle in fetal and neonatal life; 3) discuss the development of cardiovascular control during sleep; 4) discuss the effect of IUGR on sleep and the cardiovascular system and 5) discuss the future implications of melatonin therapy in IUGR pregnancies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cell injury and repair resulting from sleep loss and sleep recovery in laboratory rats.

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Everson, Carol A; Henchen, Christopher J; Szabo, Aniko; Hogg, Neil

2014-12-01

Increased cell injury would provide the type of change in constitution that would underlie sleep disruption as a risk factor for multiple diseases. The current study was undertaken to investigate cell injury and altered cell fate as consequences of sleep deprivation, which were predicted from systemic clues. Partial (35% sleep reduction) and total sleep deprivation were produced in rats for 10 days, which was tolerated and without overtly deteriorated health. Recovery rats were similarly sleep deprived for 10 days, then allowed undisturbed sleep for 2 days. The plasma, liver, lung, intestine, heart, and spleen were analyzed and compared to control values for damage to DNA, proteins, and lipids; apoptotic cell signaling and death; cell proliferation; and concentrations of glutathione peroxidase and catalase. Oxidative DNA damage in totally sleep deprived rats was 139% of control values, with organ-specific effects in the liver (247%), lung (166%), and small intestine (145%). Overall and organ-specific DNA damage was also increased in partially sleep deprived rats. In the intestinal epithelium, total sleep deprivation resulted in 5.3-fold increases in dying cells and 1.5-fold increases in proliferating cells, compared with control. Recovery sleep restored the balance between DNA damage and repair, and resulted in normal or below-normal metabolic burdens and oxidative damage. These findings provide physical evidence that sleep loss causes cell damage, and in a manner expected to predispose to replication errors and metabolic abnormalities; thereby providing linkage between sleep loss and disease risk observed in epidemiological findings. Properties of recovery sleep include biochemical and molecular events that restore balance and decrease cell injury. © 2014 Associated Professional Sleep Societies, LLC.

Characterizing cycle-to-cycle variations of the shedding cycle in the turbulent wake of a normal flat plate using generalized phase averages

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Martinuzzi, Robert

2016-11-01

Quasi-periodic vortex shedding in the turbulent wake of a thin-flat plate placed normal to a uniform stream at Reynolds number of 6700 is investigated based on Particle Image Velocimetry experiments. The wake structure and vortex formation are characterized using a generalized phase average (GPA), a refinement of the triple decomposition of Reynolds and Hussain (1970) incorporating elements of mean-field theory (Stuart, 1958). The resulting analysis highlights the importance of cycle-to-cycle variations in characterizing vortex formation, wake topology and the residual turbulent Reynolds Stresses. For example, it is shown that during high-amplitude cycles vorticity is strongly concentrated within the well-organized shed vortices, whereas during low-amplitude cycles the shed vortices are highly distorted resulting in significant modulation of the shedding frequency. It is found that high-amplitude cycles contribute more to the coherent Reynolds stress field while the low-amplitude cycles contribute to the residual stress field. It is further shown that traditional phase-averaging techniques lead to an over-estimation of the residual stress field. Natural Sciences and Engineering Research Council of Canada.

Genetic and anatomical basis of the barrier separating wakefulness and anesthetic-induced unresponsiveness.

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William J Joiner

Full Text Available A robust, bistable switch regulates the fluctuations between wakefulness and natural sleep as well as those between wakefulness and anesthetic-induced unresponsiveness. We previously provided experimental evidence for the existence of a behavioral barrier to transitions between these states of arousal, which we call neural inertia. Here we show that neural inertia is controlled by processes that contribute to sleep homeostasis and requires four genes involved in electrical excitability: Sh, sss, na and unc79. Although loss of function mutations in these genes can increase or decrease sensitivity to anesthesia induction, surprisingly, they all collapse neural inertia. These effects are genetically selective: neural inertia is not perturbed by loss-of-function mutations in all genes required for the sleep/wake cycle. These effects are also anatomically selective: sss acts in different neurons to influence arousal-promoting and arousal-suppressing processes underlying neural inertia. Supporting the idea that anesthesia and sleep share some, but not all, genetic and anatomical arousal-regulating pathways, we demonstrate that increasing homeostatic sleep drive widens the neural inertial barrier. We propose that processes selectively contributing to sleep homeostasis and neural inertia may be impaired in pathophysiological conditions such as coma and persistent vegetative states.

Quantitative differences among EMG activities of muscles innervated by subpopulations of hypoglossal and upper spinal motoneurons during non-REM sleep - REM sleep transitions: a window on neural processes in the sleeping brain.

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Rukhadze, I; Kamani, H; Kubin, L

2011-12-01

In the rat, a species widely used to study the neural mechanisms of sleep and motor control, lingual electromyographic activity (EMG) is minimal during non-rapid eye movement (non-REM) sleep and then phasic twitches gradually increase after the onset of REM sleep. To better characterize the central neural processes underlying this pattern, we quantified EMG of muscles innervated by distinct subpopulations of hypoglossal motoneurons and nuchal (N) EMG during transitions from non-REM sleep to REM sleep. In 8 chronically instrumented rats, we recorded cortical EEG, EMG at sites near the base of the tongue where genioglossal and intrinsic muscle fibers predominate (GG-I), EMG of the geniohyoid (GH) muscle, and N EMG. Sleep-wake states were identified and EMGs quantified relative to their mean levels in wakefulness in successive 10 s epochs. During non-REM sleep, the average EMG levels differed among the three muscles, with the order being N>GH>GG-I. During REM sleep, due to different magnitudes of phasic twitches, the order was reversed to GG-I>GH>N. GG-I and GH exhibited a gradual increase of twitching that peaked at 70-120 s after the onset of REM sleep and then declined if the REM sleep episode lasted longer. We propose that a common phasic excitatory generator impinges on motoneuron pools that innervate different muscles, but twitching magnitudes are different due to different levels of tonic motoneuronal hyperpolarization. We also propose that REM sleep episodes of average durations are terminated by intense activity of the central generator of phasic events, whereas long REM sleep episodes end as a result of a gradual waning of the tonic disfacilitatory and inhibitory processes.

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.

Comparative analysis of biological effect of corannulene and graphene on developmental and sleep/wake profile of zebrafish larvae.

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Li, Xiang; Zhang, Yuan; Li, Xu; Feng, DaoFu; Zhang, ShuHui; Zhao, Xin; Chen, DongYan; Zhang, ZhiXiang; Feng, XiZeng

2017-06-01

Little is known about the biological effect of non-planar polycyclic aromatic hydrocarbons (PAH) such as corannulene on organisms. In this study, we compared the effect of corannulene (non-planar PAH) and graphene (planar PAH) on embryonic development and sleep/wake behaviors of larval zebrafish. First, the toxicity of graded doses of corannulene (1, 10, and 50μg/mL) was tested in developing zebrafish embryos. Corannulene showed minimal developmental toxicity only induced an epiboly delay. Further, a significant decrease in locomotion/increase in sleep was observed in larvae treated with the highest dose (50μg/mL) of corannulene while no significant locomotion alterations were induced by graphene. Finally, the effect of corannulene or graphene on the hypocretin (hcrt) system and sleep/wake regulators such as hcrt, hcrt G-protein coupled receptor (hcrtr), and arylalkylamine N-acetyltransferase-2 (aanat2) was evaluated. Corannulene increased sleep and reduced locomotor activity and the expression of hcrt and hcrtr mRNA while graphene did not obviously disturb the sleep behavior and gene expression patterns. These results suggest that the corannulene has the potential to cause hypnosis-like behavior in larvae and provides a fundamental comparative understanding of the effects of corannulene and graphene on biology systems. Little is known about the biological effect of non-planar polycyclic aromatic hydrocarbons (PAH) such as corannulene on organisms. Here, we compare the effect of corannulene (no-planar PAH) and graphene (planar PAH) on embryonic development and sleep/wake behaviors of larval zebrafish. And we aim to investigate the effect of curvature on biological system. First, toxicity of corannulene over the range of doses (1μg/mL, 10μg/mL and 50μg/mL) was tested in developing zebrafish embryos. Corannulene has minimal developmental toxicity, only incurred epiboly delay. Subsequently, a significant decrease in locomotion/increase in sleep at the highest

Long-Term Effects of Extreme Trauma on Sleep Quality and the Circadian Rhythm of Sleep and Wakefulness: An Actigraphy Study of Utøya Survivors

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Ugland, Kaja Skullerud; Landrø, Heidi

2015-01-01

The terror attack at Utøya Island in 2011 was a national tragedy. Most of the survivors were adolescents. The aim of this study was to explore how sleep and circadian rhythm of sleep and wakefulness was affected after the Utøya massacre. In addition we wanted to examine the general sleep pattern among adolescents. Methods: 42 Utøya survivors and 46 control subjects matched on gender, age and socio- demographical variables were studied 18-30 months after the attack. Sleep was assessed by ac...

What drives slow wave activity during early non-REM sleep: Learning during prior wake or effort?

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Ziyang Li

Full Text Available What is the function of sleep in humans? One claim is that sleep consolidates learning. Slow wave activity (SWA, i.e. slow oscillations of frequency < 4 Hz, has been observed in electroencephalograms (EEG during sleep; it increases with prior wakefulness and decreases with sleep. Studies have claimed that increase in SWA in specific regions of the sleeping brain is correlated with overnight improved performance, i.e. overnight consolidation, on a demanding motor learning task. We wondered if SWA change during sleep is attributable to overnight consolidation or to metabolic demand. Participants executed out-and-back movements to a target using a pen-like cursor with their dominant hand while the target and cursor position were displayed on a screen. They trained on three different conditions on separate nights, differing in the amount and degree of rotation between the actual hand movement direction and displayed cursor movement direction. In the no-rotation (NR condition, there was no rotation. In the single rotation (SR condition, the amount of rotation remained the same throughout, and performance improved both across pre-sleep training and after sleep, i.e. overnight consolidation occurred; in the random rotation (RR condition, the amount of rotation varied randomly from trial to trial, and no overnight consolidation occurred; SR and RR were cognitively demanding. The average EEG power density of SWA for the first 30 min. of non-rapid eye movement sleep after training was computed. Both SR and RR elicited increase in SWA in the parietal region; furthermore, the topographic distribution of SWA in each was remarkably similar. No correlation was found between the overnight performance improvement on SR and the SWA change in the parietal region on measures of learning. Our results argue that regulation of SWA in early sleep is associated with high levels of cognitive effort during prior wakefulness, and not just overnight consolidation.

Sleep deprivation in Depression : What do we know, where do we go?