Nrem sleep

Brain states (wake, sleep, general anesthesia, etc.) are profoundly associated with the spatiotemporal dynamics of brain oscillations. Previous studies showed that the EEG alpha power shifted from the occipital cortex to the frontal cortex (alpha anteriorization) after being induced into a state of general anesthesia via propofol. The sleep research literature suggests that slow waves and sleep spindles are generated locally and propagated gradually to different brain regions. Since sleep and general anesthesia are conceptualized under the same framework of consciousness, the present study examines whether alpha anteriorization similarly occurs during sleep and how the EEG power in other frequency bands changes during different sleep stages...

Sleep disturbances are prevalent in children with autism spectrum disorder (ASD) and have a major impact on the quality of life. Strikingly, sleep problems are positively correlated with the severity of ASD symptoms, such as memory impairment. However, the neural mechanisms underlying sleep disturbances and cognitive deficits in ASD are largely unexplored. Here, we show that non-rapid eye movement sleep (NREMs) is highly fragmented in the 16p11.2 deletion mouse model of ASD. The degree of sleep fragmentation is reflected in an increased number of calcium transients in the activity of locus coeruleus noradrenergic (LC-NE) neurons during NREMs...

Twenty-four-hour rhythms in physiology and behaviour are shaped by circadian clocks, environmental rhythms, and feedback of behavioural rhythms onto physiology. In space, 24 h signals such as those associated with the light-dark cycle and changes in posture, are weaker, potentially reducing the robustness of rhythms. Head down tilt (HDT) bed rest is commonly used to simulate effects of microgravity but how HDT affects rhythms in physiology has not been extensively investigated. Here we report effects of -6° HDT during a 90-day protocol on 24 h rhythmicity in 20 men...

BACKGROUND: Alterations in sleep have been described in multiple health conditions and as a function of several medication effects. However, evidence generally stems from small univariate studies. Here, we apply a large-sample, data-driven approach to investigate patterns between in sleep macrostructure, quantitative sleep EEG, and health. METHODS: We use data from the MrOS Sleep Study, containing polysomnography and health data from a large sample (N = 3086) of elderly American men to establish associations between sleep macrostructure, the spectral composition of the electroencephalogram, 38 medical disorders, 2 health behaviors, and the use of 48 medications...

Accumulation of amyloid-β (Aβ) plays an important role in Alzheimer's disease (AD) pathology. There is growing evidence that disordered sleep may accelerate AD pathology by impeding the physiological clearance of Aβ from the brain that occurs in normal sleep. Therapeutic strategies for improving sleep quality may therefore help slow disease progression. It is well documented that the composition and dynamics of sleep are sensitive to ambient temperature. We therefore compared Aβ pathology and sleep metrics derived from polysomnography in 12-month-old female 3xTg-AD mice (n = 8) exposed to thermoneutral temperatures during the light period over four weeks to those of age- and sex-matched controls (n = 8) that remained at normal housing temperature (22⁰C) during the same period...

OBJECTIVE: The present study assessed the influence of physical training on cardiac autonomic activity in individuals with spinal cord injury (SCI) during different sleep stages. METHODS: Twenty-six volunteers were allocated into three groups: 9 sedentary individuals without SCI (control, CON); 8 sedentary tetraplegic individuals with chronic SCI (SED-SCI); 9 physically trained tetraplegic individuals with chronic SCI (TR-SCI). All participants underwent nocturnal polysomnography to monitor sleep stages: wakefulness, non-rapid eye movement (NREM) sleep (N1, N2, and N3 stages), and REM sleep...

We consider the disorders of arousal and sleep-related hypermotor epilepsy as genetic twin-conditions, one without, one with epilepsy. They share an augmented arousal-activity during NREM sleep with sleep-wake dissociations, culminating in sleep terrors and sleep-related hypermotor seizures with similar symptoms. The known mutations underlying the two spectra are different, but there are multifold population-genetic-, family- and even individual (the two conditions occurring in the same person) overlaps supporting common genetic roots...

Our entire life occurs in a constant alternation between wakefulness and sleep. The impossibility of living without sleep implies that any behavior must adapt to the need for sleep, and maternal behavior does not escape from this determination. Additionally, maternal behavior in mammals is a highly motivated behavior, essential for the survival of the offspring. Thus, the mother has to adapt her physiology of sleep to the constant demands of the pups, where each species will have different strategies to merge these two physiological needs...

During NREM sleep, hippocampal sharp-wave ripple (SWR) events are thought to stabilize memory traces for long-term storage in downstream neocortical structures. Within the neocortex, a set of distributed networks organized around retrosplenial cortex (RS-network) interact preferentially with the hippocampus purportedly to consolidate those traces. Transient bouts of slow oscillations and sleep spindles in this RS-network are often observed around SWRs, suggesting that these two activities are related and that their interplay possibly contributes to memory consolidation...

OBJECTIVE: Few studies have characterized the nature of sleep problems among adolescents with attention-deficit/hyperactivity disorder (ADHD) using polysomnography (PSG). Additionally, although adolescents with ADHD and adolescents with sleep disturbances display similar neurocognitive deficits, the role of sleep in contributing to neurocognitive impairment in adolescent ADHD is unknown. This study investigated differences in PSG-measured sleep among adolescents with ADHD compared with non-psychiatric controls and associations with neurocognition...

Body rocking can either induce sleep or arousal. That is, the vestibular sense influences sleep-wake states. Neuronal interactions between sleep-wake systems and vestibular systems, however, remain unclear. In this study, we found that GABAergic neurons in the lateral part of the medial vestibular nucleus (LMVN), a primary vestibular afferent projection site, control sleep-wake states. Specific inhibition of LMVN GABAergic neurons revealed that the firing of LMVN GABAergic neurons underlies stable wakefulness and smooth transitions from non-rapid-eye-movement (NREM) sleep to rapid eye movement (REM) sleep and that LMVN GABAergic neurons do not affect body balance control in freely moving conditions...

BACKGROUND: Speech graph analysis (SGA) of dreams has recently shown promise as an objective and language-invariant diagnostic tool that can aid neuropsychiatric diagnosis. Whilst the notion that dreaming mentations reflect distinct physiologic processes is not new, such studies in patients with sleep disorders remain exceptionally scarce. Here, using SGA and other dream content analyses, we set to investigate structural and thematic differences in morning dream recalls of patients diagnosed with Non-Rapid Eye Movement Parasomnia (NREMP) and Idiopathic REM Sleep Behavior Disorder (iRBD)...

We examined how aging affects the role of sleep in the consolidation of newly learned cognitive strategies. Forty healthy young adults (20-35 years) and 30 healthy older adults (60-85 years) were included. Participants were trained on the Tower of Hanoi (ToH) task, then, half of each age group were assigned to either the 90-minute nap condition, or stayed awake, before retesting. The temporal co-occurrence between slow-waves (SW) and sleep spindles (SP) during NREM sleep was examined as a function of age in relation to memory consolidation of problem-solving skills...

UNLABELLED: Paroxysmal Hypnogenic Dyskinesia (PHD) is a rare movement disorder characterized by involuntary movements, including chorea, athetosis, ballismus, and dystonia, which occur during the Non-Rapid Eye Movement (NREM) sleep stage. Therefore, the diagnosis of PHD is highly crucial due to the presence of differential diagnoses such as epilepsy and other sleep disorders. Although numerous mutations have been identified, the etiology of PHD, which arises from dysregulation in basal ganglia functions, remains unclear...

INTRODUCTION: Overlap syndrome is the association of obstructive sleep apnea (OSA) with chronic obstructive pulmonary disorder and with other chronic respiratory diseases. Patients with overlap syndrome have a worse prognosis compared with chronic obstructive pulmonary disorder or OSA alone. Additionally, patients with combined chronic obstructive pulmonary disorder and OSA are more likely to develop pulmonary hypertension and right heart failure much earlier than those without overlap...

As an intrinsic component of sleep architecture, sleep arousals represent an intermediate state between sleep and wakefulness and play an important role in sleep-wake regulation. They have been defined in an all-or-none manner, whereas they actually present a wide range of scalp-electroencephalography (EEG) activity patterns. It is poorly understood how these arousals differ in their mechanisms. Stereo-EEG (SEEG) provides the unique opportunity to record intracranial activities in superficial and deep structures in humans...

Disrupted sleep has a profound adverse impact on lives of Parkinson's disease (PD) patients and their caregivers. Sleep disturbances are exceedingly common in PD, with substantial heterogeneity in type, timing, and severity. Among the most common sleep-related symptoms reported by PD patients are insomnia, excessive daytime sleepiness, and sleep fragmentation, characterized by interruptions and decreased continuity of sleep. Alterations in brain wave activity, as measured on the electroencephalogram (EEG), also occur in PD, with changes in the pattern and relative contributions of different frequency bands of the EEG spectrum to overall EEG activity in different vigilance states consistently observed...

ETHNOPHARMACOLOGICAL RELEVANCE: Acute alcohol intoxication is one of the leading causes of coma. A well-regarded Chinese herbal formula, known as An-Gong-Niu-Huang-Wan (AGNHW), has garnered recognition for its efficacy in treating various brain disorders associated with impaired consciousness, including acute alcohol-induced coma. Despite its clinical effectiveness, the scientific community lacks comprehensive research on the mechanistic aspects of AGNHW's impact on the electroencephalogram (EEG) patterns observed during alcohol-induced coma...

UNLABELLED: Metabolism plays an important role in the maintenance of vigilance states (e.g. wake, NREM, and REM). Brain lactate fluctuations are a biomarker of sleep. Increased interstitial fluid (ISF) lactate levels are necessary for arousal and wake-associated behaviors, while decreased ISF lactate is required for sleep. ATP-sensitive potassium (K ATP ) channels couple glucose-lactate metabolism with neuronal excitability. Therefore, we explored how deletion of neuronal K ATP channel activity (Kir6...

OBJECTIVE: Parasomnia is potentially implicated in sleep pattern and sleep architecture, however, evidence is quite limited. This study aimed to investigate the association between parasomnia symptoms and sleep onset delay among children through a large epidemiological study. METHODS: Two rounds of cross-sectional studies were conducted among 21,704 children aged 3-11; one taking place in Shanghai and the other in Sanya, Hainan province. Children's sleep characteristics were evaluated using the Children's Sleep Habits Questionnaire (CSHQ)...