The effects of sleep stages and time of night on NREM sleep ERPs

We tested the hypothesis that EEG sleep stages 3 and 4 (slow-wave sleep, SWS) would be increased as a function of either acute of chronic exercise. Ten distance runners were matched with 10 nonrunners, and their sleep was recorded under both habitual (runners running and nonrunners not running, 3 night) and abruptly changed (runners not running and nonrunners running, 1 night) conditions. Analyses of both visually scored SWS and computer measures of delta activity during non-rapid eye-movement (NREM) sleep failed to support the SWS-exercise hypothesis. The runners showed a significantly higher proportion and a greater absolute amount of NREM sleep than the nonrunners. The runners showed less rapid eye-movement activity during sleep than the nonrunners under both experimental conditions, indicating a strong and unexpected effect of physical fitness on this measure. Modest afternoon exercise in nonrunners was associated with a strong trend toward elevated heart rate during sleep. Mood tests and personality profiles revealed few differences, either between groups or within groups, as a function of exercise.

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Reorganizations of latency structure within white matter from wakefulness to sleep

10.1101/2021.08.25.457605 ◽

2021 ◽

Author(s):

Bin Guo ◽

Fugen Zhou ◽

Guangyuan Zou ◽

Jun Jiang ◽

Qihong Zou ◽

...

Keyword(s):

White Matter ◽

Resting State ◽

Internal Capsule ◽

Nrem Sleep ◽

Sleep Stages ◽

Mixed Effect ◽

Corona Radiata ◽

Cross Covariance ◽

Latency Analysis ◽

The Brain

AbstractPrevious studies based on resting-state fMRI (rsfMRI) data have revealed the existence of highly reproducible latency structure, reflecting the propagation of BOLD fMRI signals, in white matter (WM). Here, based on simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) data collected from 35 healthy subjects who were instructed to sleep, we explored the alterations of propagations in WM across wakefulness and nonrapid eye movement (NREM) sleep stages. Lagged cross-covariance was computed among voxel-wise time series, followed by parabolic interpolation to determine the actual latency value in-between. In WM, regions including cerebellar peduncle, internal capsule, posterior thalamic radiation, genu of corpus callosum, and corona radiata, were found to change their temporal roles drastically, as revealed by applying linear mixed-effect model on voxel-wise latency projections across wakefulness and NREM sleep stages. Using these regions as seeds, further seed-based latency analysis revealed that variations of latency projections across different stages were underlain by inconsistent temporal shifts between each seed and the remaining part of WM. Finally, latency analysis on resting-state networks (RSNs), obtained by applying k-means clustering technique on group-level functional connectivity matrix, identified a path of signal propagations similar to previous findings in EEG during wakefulness, which propagated mainly from the brainstem upward to internal capsule and further to corona radiata. This path showed inter-RSN temporal reorganizations depending on the paired stages between which the brain transitioned, e.g., it changed, between internal capsule and corona radiata, from mainly unidirectional to clearly reciprocal when the brain transitioned from wakefulness to N3 stage. These findings suggested the functional role of BOLD signals in white matter as a slow process, dynamically modulated across wakefulness and NREM sleep stages, and involving in maintaining different levels of consciousness and cognitive processes.

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Contribution of REM sleep and N2 sleep spindles to procedural memory consolidation in Vipassana meditators and non-meditating controls.

10.31231/osf.io/e4zr2 ◽

2017 ◽

Author(s):

Elizaveta Solomonova ◽

Simon Dubé ◽

Cloé Blanchette-Carrière ◽

Arnaud Samson-Richer ◽

Michelle Carr ◽

...

Keyword(s):

Eye Movement ◽

Rem Sleep ◽

Memory Consolidation ◽

Nrem Sleep ◽

Procedural Memory ◽

Sleep Stages ◽

Sleep Spindles ◽

Meditation Practice ◽

Rapid Eye Movement ◽

Vipassana Meditation

Study objectives: Rapid eye movement (REM) sleep, non-rapid eye movement (NREM) sleep, and sleep spindles are all implicated in the consolidation of procedural memories. The relative contributions of sleep stages and sleep spindles was previously shown to depend on individual differences in task processing. Experience with Vipassana meditation is one such individual difference that has not been investigated in relation to sleep. Vipassana meditation is a form of mental training that enhances proprioceptive and somatic awareness and alters attentional style. The goal was thus to examine a potential moderating role for Vipassana meditation experience on sleep-dependent procedural memory consolidation.Methods: Groups of Vipassana meditation practitioners (N=20) and matched meditation-naïve controls (N=20) slept for a single daytime nap in the laboratory. Before and after the nap they completed a procedural task on the Wii Fit balance platform.Results: Meditators performed slightly better on the task before the nap, but the two groups improved similarly after sleep. The groups showed different patterns of sleep-dependent procedural memory consolidation: in meditators task learning was negatively correlated with density of fast and positively correlated with density of slow occipital spindles, while in controls task improvement was associated with increases in REM sleep. Meditation practitioners had a lower density of sleep spindles, especially in occipital regions.Conclusions: Results suggest that neuroplastic changes associated with sustained meditation practice may alter overall sleep architecture and reorganize sleep-dependent patterns of memory consolidation. The lower density of spindles in meditators may mean that meditation practice compensates for some of the memory functions of sleep.

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Vigilance and behavioral state-dependent modulation of cortical neuronal activity throughout the sleep/wake cycle

10.1101/2021.06.22.449480 ◽

2021 ◽

Author(s):

Aurelie Brecier ◽

Melodie Borel ◽

Nadia Urbain ◽

Luc J Gentet

Keyword(s):

Neuronal Activity ◽

Rem Sleep ◽

Barrel Cortex ◽

Field Potential ◽

Nrem Sleep ◽

Inhibitory Neurons ◽

Sleep Stages ◽

Theta Waves ◽

Physiological Diversity ◽

Activity Dynamics

GABAergic inhibitory neurons, through their molecular, anatomic and physiological diversity, provide a substrate for the modulation of ongoing cortical circuit activity throughout the sleep-wake cycle. Here, we investigated neuronal activity dynamics of parvalbumin (PV), vasoactive intestinal polypeptide (VIP) and somatostatin (SST) neurons in naturally-sleeping head-restrained mice at the level of layer 2/3 of the primary somatosensory barrel cortex of mice. Through calcium-imaging and targeted single-unit loose-patch or whole-cell recordings, we found that PV action potential (AP) firing activity was largest during both NREM (non-rapid eye movement) and REM sleep stages, that VIP neurons were activated during REM sleep and that the overall activity of SST neurons remained stable throughout the sleep/wake cycle. Analysis of neuronal activity dynamics uncovered rapid decreases in PV cell firing at wake onset followed by a progressive recovery during wake. Simultaneous local field potential (LFP) recordings further revealed that, except for SST neurons, a large proportion of neurons were modulated by ongoing delta and theta waves. During NREM sleep spindles, PV and SST activity increased and decreased, respectively. Finally, we uncovered the presence of whisking behavior in mice during REM sleep and show that the activity of VIP and SST is differentially modulated during awake and sleeping whisking bouts, which may provide a neuronal substrate for internal brain representations occurring during sleep.

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Scoring of sleep stages, breathing, and arousals

10.1093/med/9780199682003.003.0008 ◽

2017 ◽

Author(s):

Marco De Los Santos ◽

Max Hirshkowitz

Keyword(s):

Central Nervous System ◽

Nervous System ◽

American Academy ◽

Nrem Sleep ◽

Sleep Medicine ◽

General Information ◽

Sleep Stages ◽

Respiratory Effort ◽

The Usa ◽

Summary Data

This chapter summarizes scoring guidelines for sleep stages, breathing (airflow and respiratory effort), and arousals based on the principles enumerated by the American Academy of Sleep Medicine (AASM). Current established clinical standards are largely based on those published by the AASM and rules implemented by Centers for Medicare and Medicaid services in the USA. These rules include scoring of rapid eye movement (REM) and non-REM (NREM) sleep stages, central nervous system (CNS) arousals, and breathing events. Other clinically relevant polysomnographic events exist (eg, limb movements, bruxism, and electrocardiographic events) but such events are beyond the scope of this chapter. The material presented in this chapter can serve as a framework to provide general information to patients and clinicians about methods of performing the tests and gathering summary data.

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069 Chronic pain in Veterans with TBI is associated with decreased EEG slow wave coherence during NREM sleep

SLEEP ◽

10.1093/sleep/zsab072.068 ◽

2021 ◽

Vol 44 (Supplement_2) ◽

pp. A28-A29

Author(s):

Nadir Balba ◽

Christina Reynolds ◽

Mo Modarres ◽

Alisha McBride ◽

Selda Yildiz ◽

...

Keyword(s):

Chronic Pain ◽

Slow Wave ◽

Sleep Disturbances ◽

Nrem Sleep ◽

Sleep Stages ◽

Poor Sleep ◽

Signal Processing Algorithm ◽

History Of ◽

Underlying Mechanisms ◽

The Relationship

Abstract Introduction Chronic pain and sleep disturbances are intricately linked to one another, especially in individuals with a history of traumatic brain injury (TBI) who are at greater risk for both symptoms. Although prior studies have analyzed differences in sleep electroencephalogram (EEG) in these clinical populations, the association between sleep EEG slow wave coherence and pain complaints is not fully examined or known. Our novel slow wave coherence approach may provide new insights into the relationship between TBI, chronic pain, and sleep Methods Ninety-six veterans were recruited and enrolled under a VA IRB-approved protocol. Participants completed a semi-structured clinical interview to determine their history of TBI, Symptom Impact Questionnaire Revised (SIQR), a measure of chronic pain complaints, and underwent an attended overnight in-lab polysomnogram (PSG). We developed a novel computational signal processing algorithm to identify and quantify EEG slow waves within 100 ms bins across the 6 standard PSG EEG channels. When a slow wave was simultaneously observed in 4 or more of the 6 leads, slow wave coherence was inferred, and a percentage of slow wave coherence across each of the sleep stages was then calculated for each subject. Results In our sample, 65 participants (67.7%) endorsed experiencing chronic pain lasting 3 months or longer, and 54 had a history of TBI (56.3%). Participants endorsing chronic pain had a significantly lowered percent of EEG slow wave coherence during NREM sleep than subjects without chronic pain (p = 0.01). NREM EEG slow wave coherence did not correlate with SIQR scores in subjects without TBI (r = -0.03, p = 0.90), but was significantly negatively correlated in subjects with TBI (r = -0.32, p = 0.02). Conclusion EEG slow wave coherence during NREM sleep is correlated with chronic pain complaints in Veterans with a history of TBI, and could be indicative of neuronal dysfunction during sleep. Further research on slow wave coherence is warranted to understand the underlying mechanisms for the association between chronic pain and poor sleep following TBI. Support (if any) D01 W81XWH-17-1-0423

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Nocturnal Psychophysiological Correlates of Somatic Conditions and Sleep Disorders

The International Journal of Psychiatry in Medicine ◽

10.2190/r510-bkx2-bkjk-kv4h ◽

1975 ◽

Vol 6 (1-2) ◽

pp. 43-62 ◽

Cited By ~ 9

Author(s):

Joyce D. Kales ◽

Anthony Kales

Keyword(s):

Sleep Disorders ◽

Sleep Stage ◽

Symptomatic Relief ◽

Nrem Sleep ◽

Normal Subjects ◽

Sleep Stages ◽

Sleep Laboratory ◽

Drug Induced ◽

Night Terrors ◽

Psychophysiological Correlates

Modern sleep research studies have provided the practicing physician with considerable new information concerning the basic psychophysiology of sleep, the effects of medical conditions on sleep and the role of maturational and emotional factors in producing certain sleep disorders. Medical and psychiatric disorders, sleep disorders and drug-induced sleep stage alterations are studied in the sleep laboratory using the same techniques developed to analyze sleep patterns in normal subjects. After initial sleep laboratory adaptation, a profile of the sleep characteristics of various clinical conditions is obtained. This profile can be compared to sleep profiles of normal subjects as well as to the effects on sleep of subsequent experimental or therapeutic procedures. Various studies have shown that coronary artery, duodenal ulcer and nocturnal headache patients experience angina, increased gastric acid secretion and migraine or cluster headaches, respectively during REM sleep. Adult nocturnal asthmatic episodes occur out of all sleep stages while attacks of dyspnea in asthmatic children occur in all stages except stage 4 sleep. Hypothyroid patients show decreases in stages 3 and 4 sleep, while in hyperthyroid patients the percentage of time spent in stages 3 and 4 sleep is markedly increased. Enuretic episodes occur predominantly in non-rapid eye movement (NREM) sleep. Sleepwalking and night terror episodes occur exclusively out of NREM sleep, particularly from stages 3 and 4 sleep. Most child somnambulists and children with night terrors “outgrow” this disorder, suggesting a delayed maturation of the central nervous system. Stimulant drugs are effective in the treatment of the sleep attacks of narcolepsy and in treating certain cases of hypersomnia, while imipramine is an effective treatment for the auxiliary symptoms of narcolepsy. Psychological disturbances are frequent in adult somnambulism and night terrors as well as in hypersomnia and insomnia. Proper pharmacologic treatment to provide symptomatic relief for insomnia is recommended to enhance the psychotherapeutic process.

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Progressive changes in airway resistance during sleep

Journal of Applied Physiology ◽

10.1152/jappl.1996.81.1.282 ◽

1996 ◽

Vol 81 (1) ◽

pp. 282-292 ◽

Cited By ~ 31

Author(s):

A. Kay ◽

J. Trinder ◽

Y. Kim

Keyword(s):

Airway Resistance ◽

Slow Wave Sleep ◽

Full Range ◽

Sleep Onset ◽

Upper Airway ◽

Young Male ◽

Nrem Sleep ◽

Sleep Stages ◽

Compensatory Mechanisms ◽

Sleep Period

Ventilation (V) decreases during sleep while upper airway resistance (UAR) increases. A number of studies have suggested that in normal healthy individuals the changes in the two variables are reciprocal. Other findings, however, suggest that the relationship between V and UAR may change as non-rapid-eye-movement (NREM) sleep progresses such that most of the change in V occurs early during the sleep period, whereas the most marked changes in UAR occur later during established NREM sleep. However, no study has examined the progressive development of changes in both V and UAR over the NREM sleep period. This study examined V and UAR over one NREM sleep period in two groups of healthy young male subjects: a "slow-wave sleep (SWS) group" (n = 8) in which the subjects obtained the full range of NREM sleep stages from wakefulness to stage 4 NREM sleep and a "no-SWS group" (n = 5) in which the subjects did not attain SWS but spent a prolonged period in stage 2 NREM sleep that was repeatedly interrupted by arousals. Results showed that the most marked changes in V occurred early during the sleep period in association with relatively small increases in UAR. Once NREM sleep became established, further attenuation of V was minimal despite marked and progressive increases in UAR. The progressive increase in UAR occurred in association with increasing delta (0.4- to 3.0-Hz) electroencephalographic activity and did not occur in the no-SWS group. We interpret these findings to indicate that factors in addition to UAR contribute to the reduction in V early in sleep onset, whereas later, during NREM sleep, compensatory mechanisms are activated to allow for maintenance of V in the context of larger increases in UAR.

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Don't count your chickens before they're hatched: Elaborative encoding in REM dreaming in face of the physiology of sleep stages

Behavioral and Brain Sciences ◽

10.1017/s0140525x1300126x ◽

2013 ◽

Vol 36 (6) ◽

pp. 613-614

Author(s):

Gaétane Deliens ◽

Sophie Schwartz ◽

Philippe Peigneux

Keyword(s):

Eye Movement ◽

Rem Sleep ◽

De Novo ◽

Nrem Sleep ◽

Sleep Stages ◽

Rapid Eye Movement ◽

Hidden Patterns ◽

Episodic Memories ◽

Novel Associations

AbstractLlewellyn suggests that episodic memories undergo “elaborative encoding” during rapid eye movement (REM) dreams, generating novel associations between recent and remote memories that are then instantiated during non-REM (NREM) sleep. This hypothesis conflicts with our knowledge of the physiology of NREM and then REM sleep stages and their ordered succession. Moreover, associations during sleep might also involve the extraction of hidden patterns rather than de novo associations.

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