NONLINEAR ANALYSIS OF EEG SLOW-WAVE ACTIVITY DURING SLEEP AND SLEEP REGULATION MODELING: A STUDY IN NARCOLEPTIC PATIENTS UNDER BED REST CONDITIONS

AbstractStudy ObjectivesSleep disturbances and insomnia are highly prevalent in children with Autism Spectrum Disorder (ASD). Sleep homeostasis, a fundamental mechanism of sleep regulation that generates pressure to sleep as a function of wakefulness, has not been studied in children with ASD so far, and its potential contribution to their sleep disturbances remains unknown. Here, we examined whether slow wave activity (SWA), a measure that is indicative of sleep pressure, differs in children with ASD.MethodsIn this case-control study, we compared overnight electroencephalogram (EEG) recordings that were performed during Polysomnography (PSG) evaluations of 29 children with ASD and 23 typically developing children.ResultsChildren with ASD exhibited significantly weaker SWA power, shallower SWA slopes, and a decreased proportion of slow wave sleep in comparison to controls. This difference was largest during the first two hours following sleep onset and decreased gradually thereafter. Furthermore, SWA power of children with ASD was significantly, negatively correlated with the time of their sleep onset in the lab and at home, as reported by parents.ConclusionsThese results suggest that children with ASD may have a dysregulation of sleep homeostasis that is manifested in reduced sleep pressure. The extent of this dysregulation in individual children was apparent in the amplitude of their SWA power, which was indicative of the severity of their individual sleep disturbances. We, therefore, suggest that disrupted homeostatic sleep regulation may contribute to sleep disturbances in children with ASD.Statement of significanceSleep disturbances are apparent in 40-80% of children with autism. Homeostatic sleep regulation, a mechanism that increases the pressure to sleep as a function of prior wakefulness, has not been studied in children with autism. Here, we compared Polysomnography exams of 29 children with autism and 23 matched controls. We found that children with autism exhibited reduced slow-wave-activity power and shallower slopes, particularly during the first two hours of sleep. This suggests that they develop less pressure to sleep. Furthermore, the reduction in slow-wave-activity was associated with the severity of sleep disturbances as observed in the laboratory and as reported by parents. We, therefore, suggest that disrupted homeostatic sleep regulation may contribute to sleep disturbances of children with autism.

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Varying photoperiod in the laboratory rat: profound effect on 24-h sleep pattern but no effect on sleep homeostasis

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1995.269.3.r691 ◽

1995 ◽

Vol 269 (3) ◽

pp. R691-R701 ◽

Cited By ~ 3

Author(s):

P. Franken ◽

I. Tobler ◽

A. A. Borbely

Keyword(s):

Eye Movement ◽

Slow Wave ◽

Wave Activity ◽

Slow Wave Activity ◽

Sleep Pattern ◽

Rapid Eye Movement ◽

Rapid Eye Movement Sleep ◽

Sleep Regulation ◽

Marked Rise ◽

Laboratory Rats

To assess the influence of the photoperiod on sleep regulation, laboratory rats were adapted to a long photoperiod (LPP; 16:8-h light-dark cycle, LD 16:8) or a short photoperiod (SPP; LD 8:16). The electroencephalogram (EEG) and cortical temperature (TCRT) were continuously recorded for a baseline day, a 24-h sleep deprivation (SD) period, and a recovery day. Data obtained previously for LD 12:12 served for comparison. Whereas the photoperiod exerted a prominent effect on the 24-h sleep pattern, the 24-h baseline level of sleep and the response to SD were little affected. Recovery from SD was characterized by a marked rise in rapid eye movement sleep, a moderate rise in non-rapid eye movement sleep, and an initial enhancement of EEG slow-wave activity followed by a decrease below baseline. The amplitude and phase of the "unmasked" 24-h component of TCRT did not differ between LPP and SPP. Computer simulations demonstrated that the changes of TCRT and EEG slow-wave activity can be largely accounted for by the sequence of the vigilance states. We conclude that the photoperiod does not affect the basic processes underlying sleep regulation.

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The neural architecture of sleep regulation – insights from Drosophila

Neuroforum ◽

10.1515/nf-2021-0018 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Raquel Suárez-Grimalt ◽

Davide Raccuglia

Keyword(s):

Neural Networks ◽

Slow Wave ◽

Sensory Processing ◽

Model Organism ◽

Wave Activity ◽

Slow Wave Activity ◽

Sleep Regulation ◽

Neural Architecture ◽

Waking And Sleep ◽

Functional Components

Abstract The neural mechanisms that balance waking and sleep to ensure adequate sleep quality in mammals are highly complex, often eluding functional insight. In the last two decades, researchers made impressive progress in studying the less complex brain of the invertebrate model organism Drosophila melanogaster, which has led to a deeper understanding of the neural principles of sleep regulation. Here, we will review these findings to illustrate that neural networks require sleep to undergo synaptic reorganization that allows for the incorporation of experiences made during the waking hours. Sleep need, therefore, can arise as a consequence of sensory processing, often signalized by neural networks as they synchronize their electrical patterns to generate slow-wave activity. The slow-wave activity provides the neurophysiological basis to establish a sensory gate that suppresses sensory processing to provide a resting phase which promotes synaptic rescaling and clearance of metabolites from the brain. Moreover, we demonstrate how neural networks for homeostatic and circadian sleep regulation interact to consolidate sleep into a specific daily period. We particularly highlight that the basic functions and physiological principles of sleep are highly conserved throughout the phylogenetic spectrum, allowing us to identify the functional components and neural interactions that construct the neural architecture of sleep regulation.

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Interleukin 1 alters rat sleep: temporal and dose-related effects

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1991.260.1.r52 ◽

1991 ◽

Vol 260 (1) ◽

pp. R52-R58 ◽

Cited By ~ 25

Author(s):

M. R. Opp ◽

F. Obal ◽

J. M. Krueger

Keyword(s):

Eye Movement ◽

Slow Wave ◽

Brain Temperature ◽

Interleukin 1 ◽

Wave Activity ◽

Slow Wave Activity ◽

Rapid Eye Movement ◽

Rapid Eye Movement Sleep ◽

Sleep Regulation ◽

High Doses

Rats received various doses of interleukin 1 (IL-1) (range, 0.5-25.0 ng) or pyrogen-free saline intracerebroventricularly during the rest (light) and the active (dark) cycles of the day, and sleep-wake activity and brain temperature were determined for 6 h. Low doses of IL-1 (0.5 ng at night, 2.5 ng during the day) increased both the duration of non-rapid-eye-movement sleep (NREMS) and electroencephalogram (EEG) slow-wave activity during NREMS episodes. Increasing doses of IL-1 had divergent effects on NREMS duration and EEG slow-wave activity, and the direction of the changes depended on the diurnal cycle. Thus NREMS duration was promoted at night and EEG slow-wave amplitudes during the day, whereas NREMS duration during the day and EEG slow-wave amplitudes at night were suppressed after higher doses of IL-1. High doses of IL-1 also induced decreases in rapid-eye-movement sleep during both phases of the day. Each dose of IL-1 that promoted NREMS also tended to increase brain temperature. These results demonstrate that IL-1 promotes NREMS in the rat. However, unlike previously reported findings in rabbits, the circadian rhythm of sleep regulation strongly interferes with the sleep-promoting activity of IL-1 in rats.

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Dynamics of slow wave activity in narcoleptic patients under bed rest conditions

Electroencephalography and Clinical Neurophysiology ◽

10.1016/0013-4694(95)00138-7 ◽

1995 ◽

Vol 95 (6) ◽

pp. 414-425 ◽

Cited By ~ 25

Author(s):

L. Nobili ◽

A. Besset ◽

F. Ferrillo ◽

G. Rosadini ◽

G. Schiavi ◽

...

Keyword(s):

Slow Wave ◽

Bed Rest ◽

Wave Activity ◽

Slow Wave Activity

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Correlation dimension of EEG slow-wave activity during sleep in narcoleptic patients under bed rest conditions

International Journal of Psychophysiology ◽

10.1016/s0167-8760(99)00041-0 ◽

1999 ◽

Vol 34 (1) ◽

pp. 37-43 ◽

Cited By ~ 8

Author(s):

Raffaele Ferri ◽

Salvatore Pettinato ◽

Lino Nobili ◽

Michel Billiard ◽

Franco Ferrillo

Keyword(s):

Slow Wave ◽

Correlation Dimension ◽

Bed Rest ◽

Wave Activity ◽

Slow Wave Activity

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118 Complexity of EEG slow-wave activity and sleep regulation modeling

International Journal of Psychophysiology ◽

10.1016/s0167-8760(98)90118-0 ◽

1998 ◽

Vol 30 (1-2) ◽

pp. 47

Author(s):

Raffaele Ferri ◽

Salvatore Pettinato ◽

Filippa Alicata Stefano

Keyword(s):

Slow Wave ◽

Wave Activity ◽

Slow Wave Activity ◽

Sleep Regulation

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Dissimilarity of slow-wave activity enhancement by torpor and sleep deprivation in a hibernator

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1998.275.4.r1110 ◽

1998 ◽

Vol 275 (4) ◽

pp. R1110-R1117 ◽

Cited By ~ 11

Author(s):

Arjen M. Strijkstra ◽

Serge Daan

Keyword(s):

Sleep Deprivation ◽

Slow Wave ◽

Wave Activity ◽

Ground Squirrels ◽

Slow Wave Activity ◽

Rapid Eye Movement Sleep ◽

Frequency Range ◽

Sleep Regulation ◽

Normal Sleep ◽

Activity Enhancement

Sleep regulation processes have been hypothesized to be involved in function and timing of arousal episodes in hibernating ground squirrels. We investigated the importance of sleep regulation during arousal episodes by sleep deprivation experiments. After sleep deprivation of 4, 12, and 24 h, starting 4 h after onset of euthermy, a duration-dependent enhancement of slow-wave activity (SWA) of the cortical electroencephalogram during non-rapid eye movement sleep was found, as expected for normal sleep regulation. When sleep deprivation was applied during the initial phase of the arousal episode, in which effects of prior torpor were present in undisturbed recordings, no subsequent recurrence of SWA was found. In addition, prior torpor induced a reduction in the spectral activity of the sigma frequency range (7–14 Hz), which was not observed after sleep deprivation. The effects of torpor and sleep deprivation on subsequent SWA appear qualitatively different. This indicates that effects of deep torpor on sleep are dissimilar to normal sleep regulation.

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