Commonalities and Differences in NREM Parasomnias and Sleep-Related Epilepsy: Is There a Continuum Between the Two Conditions?

Introduction: Differential diagnosis between disorders of arousal (DoA) and sleep-related hypermotor epilepsy (SHE) often represents a clinical challenge. The two conditions may be indistinguishable from a semiological point of view and the scalp video-polysomnography is often uninformative. Both disorders are associated with variable hypermotor manifestations ranging from major events to fragments of a hierarchical continuum of increasing intensity, complexity, and duration. Given their semiological overlap we decided to explore the sleep texture of DoA and SHE seeking for similarities and differences.Methods: We analyzed sleep macrostructure and CAP (cyclic alternating pattern) parameters in a cohort of 35 adult DoA patients, 40 SHE patients and 24 healthy sleepers, all recorded and scored in the same sleep laboratory. Nocturnal behavioral manifestations included minor motor events, paroxysmal arousals and major attacks in SHE, and simple, rising, or complex arousal movements in DoA.Results: Compared to healthy controls, DoA and SHE showed similar amounts of sleep efficiency, light sleep, deep sleep, REM sleep, CAP subtypes. Both groups also showed slow wave sleep fragmentation and an increased representation of stage N3 in the second part of the night. The only discriminating elements between the two conditions regarded sleep length (more reduced in DoA) and sleep instability (more elevated in SHE). In DoA recordings, all motor episodes arose from NREM sleep: 37% during light NREM stages and 63% during stage N3 (simple arousal movements: 94%). In SHE recordings, 57% of major attacks occurred during stage N3.Conclusions: So far, emphasis has been placed on the differentiation of sleep-related epilepsy and NREM arousal disorders. However, the impressive analogies between DoA and SHE suggest the existence of an underestimated continuum across the conditions, linked by increased levels of sleep instability, higher amounts of slow wave sleep and NREM/REM sleep imbalance. Sleep texture is extremely similar in the two conditions, although CAP metrics disclose quantitative differences. In particular, SHE patients show a higher arousal instability compared to DoA subjects. Given their clinical and epidemiological overlap, a common genetic background is also hypothesized. In such a perspective, we suggest that the consolidated dichotomy DoA vs. SHE should be reappraised.

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129 Greater NREM Sleep Rebound in Response to Experimental Sleep Disturbance Associated with Higher Inflammatory Resolution in Humans

SLEEP ◽

10.1093/sleep/zsab072.128 ◽

2021 ◽

Vol 44 (Supplement_2) ◽

pp. A52-A53

Author(s):

Larissa Engert ◽

Marc Dubourdeau ◽

Rammy Dang ◽

Janet Mullington ◽

Monika Haack

Keyword(s):

Sleep Disturbance ◽

Slow Wave ◽

Rem Sleep ◽

Sleep Disturbances ◽

Slow Wave Sleep ◽

Sleep Onset ◽

Nrem Sleep ◽

Low Grade ◽

German Research Foundation ◽

Recovery Sleep

Abstract Introduction Sleep disturbances deteriorate immune function by not only affecting pro-inflammatory pathways, but also inflammatory resolution pathways, which actively terminate inflammation. It is assumed that slow wave sleep (SWS) amount and slow wave activity (SWA) convey the immune-supportive functions of sleep. We investigated whether changes in SWS induced by experimental sleep disturbance followed by recovery sleep predict changes in inflammatory resolution mediators. Methods The randomized controlled within-subjects trial (N=24, 20-42 years, 12 women) consisted of two 19-day in-hospital protocols (experimental sleep disturbance/control). After three nights of baseline sleep (8h/night), participants in the experimental sleep disturbance condition were exposed to three cycles of three nights of disturbed sleep (delayed sleep-onset, hourly sleep disruption, advanced sleep-offset) followed by one night of 8h-recovery sleep. The protocol ended with three nights of recovery sleep. In the control condition, participants had uninterrupted sleep (8h/night). Sleep (PSG) and resolvin lipid mediators in plasma (1100h, LC-MS/MS) were assessed at baseline, during the last cycle of sleep disturbance, and during/after the first and third night of final recovery sleep. Data were analyzed using generalized linear mixed models and Pearson/Spearman correlations. Results As expected, SWS amount decreased during experimental sleep disturbance and increased during the first recovery sleep night (p<.001). Similarly, resolvin (Rv) D2 and RvD3 decreased during sleep disturbance and RvD2 increased with subsequent recovery sleep (p<.001). The SWS response did not correlate with the resolvin response to sleep disturbance or to recovery sleep. However, the NREM sleep response correlated with the resolvin response during the third recovery sleep night, i.e., a greater NREM response was associated with a greater RvD2 and RvD3 response (r=.68, p=.002; r=.58, p=.012). In contrast, a greater REM sleep response was associated with a lower resolvin response (r=−.63, p=.005; r=−.66, p=.003). Conclusion These data suggest that during recovery from sleep disturbance, NREM rather than REM sleep promotes inflammatory resolution, thereby acting as the sleep state that protects against low-grade systemic inflammation, which has been frequently observed as a consequence of sleep disturbances. Analysis whether SWA is related to inflammatory resolution is in progress. Support (if any) NIH/NINDS R01-NS091177; NIH/NCRR UL1-RR02758, M01-RR01032; German Research Foundation (DFG) EN1291/1-1.

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Parasomnias

10.2310/psych.13050 ◽

2018 ◽

Author(s):

KyoungBin Im

Keyword(s):

Mental Disorders ◽

Rem Sleep ◽

Slow Wave Sleep ◽

Rem Sleep Behavior Disorder ◽

Behavior Disorder ◽

Nrem Sleep ◽

Normal Subjects ◽

Related Phenomenon ◽

Sleep Behavior ◽

Diagnostic And Statistical Manual

Parasomnias have long been recognized as part of sleep-related disorders or diseases in the mental disorders classification system such as Diagnostic and Statistical Manual of Mental Disorders. Nevertheless, many parasomnia symptoms are considered as a transient deviation from the norm in otherwise normal subjects due to disrupted status of consciousness. Sleep states are classified as rapid eye movement (REM) sleep and non-REM (NREM) sleep; similarly, parasomnias are classified as NREM-related parasomnias and REM-related parasomnias. NREM-related parasomnias share common pathophysiology of arousal-related phenomenon out of slow-wave sleep. Although listed as REM parasomnia disorders, nightmares and sleep paralysis are still considered comorbid symptoms or signs of other sleep disorders or mental disorders. Only REM sleep behavior disorder (RBD) is considered a relatively homogenous disease entity among all parasomnia diagnoses. Although RBD is the most newly added disorder entity in parasomnias, it is the most rigorously studied parasomnia such as RBD is strongly and clearly associated with concomitant or future developing neurodegenerative disease. This review contains 1 figure, 4 tables, and 18 references. Key Words: confusional arousals, dream enactment, pseudo-RBD, REM sleep behavior disorder, sleep-related eating, sleep terror, sleepwalking

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Neostriatal administration of somatostatin: differential effect of small and large doses on behavior and motor control

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y77-034 ◽

1977 ◽

Vol 55 (2) ◽

pp. 234-242 ◽

Cited By ~ 49

Author(s):

M. Rezek ◽

V. Havlicek ◽

L. Leybin ◽

C. Pinsky ◽

E. A. Kroeger ◽

...

Keyword(s):

Motor Control ◽

Eye Movements ◽

Slow Wave ◽

Rem Sleep ◽

Differential Effect ◽

Slow Wave Sleep ◽

Small Doses ◽

Freely Moving ◽

Behavioral Excitation ◽

Higher Doses

The administration of small doses of somatostatin (SRIF) (0.01 and 0.1 μg) into the neostriatal complex of unrestrained, freely moving rats induced general behavioral excitation associated with a variety of stereotyped movements, tremors, and a reduction of rapid eye movements (REM) and deep slow wave sleep (SWS). In contrast, the higher doses of SRIF (1.0 and 10.0 μg) caused movements to be uncoordinated and frequently induced more severe difficulties in motor control such as contralateral hemiplegia-in-extension which restricted or completely prevented the expression of normal behavioral patterns. As a result, the animals appeared drowsy and inhibited. Analysis of the sleep-waking cycle revealed prolonged periods of a shallow SWS while REM sleep and deep SWS were markedly reduced; electroencephalogram recordings revealed periods of dissociation from behavior. The administration of endocrinologically inactive as well as the active analogues of SRIF failed to induce effects comparable with those observed after the administration of the same dose of the native hormone (10.0 μg).

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Bidirectional Interaction of Hippocampal Ripples and Cortical Slow Waves Leads to Coordinated Spiking Activity During NREM Sleep

Cerebral Cortex ◽

10.1093/cercor/bhaa228 ◽

2020 ◽

Vol 31 (1) ◽

pp. 324-340

Author(s):

Pavel Sanda ◽

Paola Malerba ◽

Xi Jiang ◽

Giri P Krishnan ◽

Jorge Gonzalez-Martinez ◽

...

Keyword(s):

Slow Wave ◽

Memory Consolidation ◽

Slow Wave Sleep ◽

Nrem Sleep ◽

Slow Waves ◽

Slow Oscillation ◽

Cortical Input ◽

Sharp Wave ◽

Up States ◽

Intracranial Recordings

Abstract The dialogue between cortex and hippocampus is known to be crucial for sleep-dependent memory consolidation. During slow wave sleep, memory replay depends on slow oscillation (SO) and spindles in the (neo)cortex and sharp wave-ripples (SWRs) in the hippocampus. The mechanisms underlying interaction of these rhythms are poorly understood. We examined the interaction between cortical SO and hippocampal SWRs in a model of the hippocampo–cortico–thalamic network and compared the results with human intracranial recordings during sleep. We observed that ripple occurrence peaked following the onset of an Up-state of SO and that cortical input to hippocampus was crucial to maintain this relationship. A small fraction of ripples occurred during the Down-state and controlled initiation of the next Up-state. We observed that the effect of ripple depends on its precise timing, which supports the idea that ripples occurring at different phases of SO might serve different functions, particularly in the context of encoding the new and reactivation of the old memories during memory consolidation. The study revealed complex bidirectional interaction of SWRs and SO in which early hippocampal ripples influence transitions to Up-state, while cortical Up-states control occurrence of the later ripples, which in turn influence transition to Down-state.

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Insights into paradoxical (REM) sleep homeostatic regulation in mice using an innovative automated sleep deprivation method

SLEEP ◽

10.1093/sleep/zsaa003 ◽

2020 ◽

Vol 43 (7) ◽

Cited By ~ 3

Author(s):

Sébastien Arthaud ◽

Paul-Antoine Libourel ◽

Pierre-Hervé Luppi ◽

Christelle Peyron

Keyword(s):

Slow Wave ◽

Rem Sleep ◽

High Efficiency ◽

Environmental Changes ◽

Slow Wave Sleep ◽

Paradoxical Sleep ◽

Corticosterone Level ◽

Plasma Corticosterone ◽

Homeostatic Regulation ◽

External Modulation

Abstract Identifying the precise neuronal networks activated during paradoxical sleep (PS, also called REM sleep) has been a challenge since its discovery. Similarly, our understanding of the homeostatic mechanisms regulating PS, whether through external modulation by circadian and ultradian drives or via intrinsic homeostatic regulation, is still limited, largely due to interfering factors rendering the investigation difficult. Indeed, none of the studies published so far were able to manipulate PS without significantly altering slow-wave sleep and/or stress level, thus introducing a potential bias in the analyses. With the aim of achieving a better understanding of PS homeostasis, we developed a new method based on automated scoring of vigilance states—using electroencephalogram and electromyogram features—and which involves closed-loop PS deprivation through the induction of cage floor movements when PS is detected. Vigilance states were analyzed during 6 and 48 h of PS deprivation as well as their following recovery periods. Using this new automated methodology, we were able to deprive mice of PS with high efficiency and specificity, for short or longer periods of time, observing no sign of stress (as evaluated by plasma corticosterone level and sleep latency) and requiring no human intervention or environmental changes. We show here that PS can be homeostatically modulated and regulated while no significant changes are induced on slow-wave sleep and wakefulness, with a PS rebound duration depending on the amount of prior PS deficit. We also show that PS interval duration is not correlated with prior PS episode duration in the context of recovery from PS deprivation.

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Each distinct type of mental state is supported by specific brain functions

Behavioral and Brain Sciences ◽

10.1017/s0140525x00434023 ◽

2000 ◽

Vol 23 (6) ◽

pp. 941-943 ◽

Cited By ~ 5

Author(s):

Claude Gottesmann

Keyword(s):

Slow Wave ◽

Mental State ◽

Rem Sleep ◽

Psychological Functioning ◽

Slow Wave Sleep ◽

Mental Content ◽

Distinct Type ◽

Inhibitory Processes ◽

Brain Functions

Reflective waking mentation is supported by cortical activating and inhibitory processes. The thought-like mental content of slow wave sleep appears with lower levels of both kinds of influence. During REM sleep, the equation: activation + disinhibition + dopamine may explain the often psychotic-like mode of psychological functioning.[Hobson et al.; Nielsen; Revonsuo; Solms; Vertes & Eastman]

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