Publications by authors named "Siclari F"

Disorders of Arousal (DOA) are non-rapid eye movement (NREM) parasomnias traditionally regarded as unconscious states. However, recent research challenges this assumption. This narrative review aims to explore the presence and qualitative features of conscious experiences in patients with DOA during their episodes.

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Dreaming, a common yet mysterious cognitive phenomenon, is an involuntary process experienced by individuals during sleep. Although the fascination with dreams dates back to ancient times and gained therapeutic significance through psychoanalysis in the early twentieth century, its scientific investigation only gained momentum with the discovery of rapid eye movement (REM) sleep in the 1950s. This review synthesises current research on the neurobiological and psychological aspects of dreaming, including factors influencing dream recall and content, neurophysiological correlates, and experimental models, and discusses the implications for clinical practice.

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Sleepwalking and related parasomnias are thought to result from incomplete awakenings out of non-rapid eye movement (non-REM) sleep. Non-REM parasomnia behaviours have been described as unconscious and automatic, or related to vivid, dream-like conscious experiences. Similarly, some observations have suggested that patients are unresponsive during episodes, while others that they can interact with their surroundings.

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Article Synopsis
  • * Key findings showed that higher scores on the Epworth Sleepiness Scale and the presence of insomnia symptoms were associated with a greater risk of developing MDD, with specific hazard ratios calculated for both factors.
  • * Notably, men with increased rapid eye movement (REM) sleep had a higher MDD incidence, while women with higher delta power in their sleep showed a lower incidence, indicating gender differences in how sleep affects depression risk.
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Sleepwalking and related parasomnias result from incomplete awakenings out of non-rapid eye movement sleep. Behavioral episodes can occur without consciousness or recollection, or in relation to dream-like experiences. To understand what accounts for these differences in consciousness and recall, here we recorded parasomnia episodes with high-density electroencephalography (EEG) and interviewed participants immediately afterward about their experiences.

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  • Sleep misperception is when people think they didn't sleep much, even though their sleep was normal according to tests.
  • Good sleepers usually know how long they actually slept, while some people with insomnia often think they slept less than they did.
  • Recent studies show that people with insomnia might have different brain activity patterns during sleep that make them feel awake, especially during the REM sleep stage.
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Whole-night sleep electroencephalogram (EEG) is plagued by several types of large-amplitude artifacts. Common approaches to remove them are fraught with issues: channel interpolation, rejection of noisy intervals, and independent component analysis are time-consuming, rely on subjective user decisions, and result in signal loss. Artifact Subspace Reconstruction (ASR) is an increasingly popular approach to rapidly and automatically clean wake EEG data.

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  • Insomnia and hypersomnia are considered indicators of major depressive disorder (MDD) subtypes, but this study aimed to see if these sleep changes can be objectively measured using polysomnography (PSG).
  • A total of 1820 participants underwent PSG and psychiatric interviews to determine their MDD subtype, with linear regression analysis used to identify sleep measure associations.
  • Results showed that current melancholic MDD was linked to lower delta power and sleep efficiency, as well as more nighttime awakenings, while remitted unspecified MDD was associated with higher rapid eye movement density, suggesting distinct sleep patterns across MDD subtypes.
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It is currently unclear which patients with obstructive sleep apnea (OSA) are at increased cardiovascular risk. To investigate the value of pulse wave amplitude drops (PWADs), reflecting sympathetic activations and vasoreactivity, as a biomarker of cardiovascular risk in OSA. PWADs were derived from pulse oximetry-based photoplethysmography signals in three prospective cohorts: HypnoLaus ( = 1,941), the Pays-de-la-Loire Sleep Cohort (PLSC;  = 6,367), and "Impact of Sleep Apnea syndrome in the evolution of Acute Coronary syndrome.

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Study Objectives: Although recent investigations combining noradrenergic and antimuscarinic drugs have shown promising short-term results to treat obstructive sleep apnea (OSA), the mid-term effect and optimal dosage remain uncertain. The present study aimed to evaluate the effect of 1 week of 5 mg oxybutynin and 6 mg reboxetine (oxy-reb) on OSA versus placebo.

Methods: We performed a randomized, placebo-controlled, double-blind, crossover trial comparing the effect of 1 week of oxy-reb versus 1 week of placebo on OSA severity.

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  • This study explores the relationship between sleep spindles (brain activity during sleep) and various psychiatric disorders, particularly focusing on schizophrenia (SZ) and other disorders with psychotic symptoms.
  • Researchers recorded sleep patterns in 1,037 participants, measuring sleep spindle parameters to compare those with schizophrenia against individuals with schizoaffective disorders and bipolar disorder types I and II.
  • Findings revealed that individuals with schizophrenia had reduced sleep spindle density and duration, while those with manic symptoms displayed distinct spindle characteristics, suggesting that sleep spindle deficits may serve as a biomarker for schizophrenia and differ across disorders.
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Background Poor sleep quality is associated with increased incident hypertension. However, few studies have investigated the impact of objective sleep structure parameters on hypertension. This study investigated the association between sleep macrostructural and microstructural parameters and incident hypertension in a middle- to older-aged sample.

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Study Objectives: Sleepwalking, confusional arousals, and sleep terrors are parasomnias occurring out of non-rapid eye movement (NREM) sleep. Several previous studies have described EEG changes associated with NREM parasomnia episodes, but it remains unclear whether these changes are specific to parasomnia episodes or whether they are part of the normal awakening process. Here we directly compared regional brain activity, measured with high-density (hd-) EEG, between parasomnia episodes and normal awakenings (without behavioral manifestations of parasomnia).

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What accounts for feeling deeply asleep? Standard sleep recordings only incompletely reflect subjective aspects of sleep and some individuals with so-called sleep misperception frequently feel awake although sleep recordings indicate clear-cut sleep. To identify the determinants of sleep perception, we performed 787 awakenings in 20 good sleepers and 10 individuals with sleep misperception and interviewed them about their subjective sleep depth while they underwent high-density EEG sleep recordings. Surprisingly, in good sleepers, sleep was subjectively lightest in the first 2 h of non-rapid eye movement (NREM) sleep, generally considered the deepest sleep, and deepest in rapid eye movement (REM) sleep.

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Benzodiazepines have proven to be highly effective for treating insomnia and anxiety. Although considered safe when taken for a short period of time, a major risk-benefit dilemma arises in the context of long-term use, relating to addiction, withdrawal symptoms, and potential side effects. For these reasons, benzodiazepines are not recommended for treating chronic sleep disorders, anxiety disorders, nor for people over the age of 65, and withdrawal among long-term users is a public health issue.

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Sleep spindles of non-REM sleep are transient, waxing-and-waning 10-16 Hz EEG oscillations, whose cortical synchronization depends on the engagement of thalamo-cortical loops. However, previous studies in animal models lacking the corpus callosum due to agenesis or total callosotomy and in humans with agenesis of the corpus callosum suggested that cortico-cortical connections may also have a relevant role in cortical (inter-hemispheric) spindle synchronization. Yet, most of these works did not provide direct quantitative analyses to support their observations.

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Objectives: Existing data suggest that smoking may be associated with sleep disturbances. This study aimed to determine the association between smoking and both subjective and objective sleep quality.

Methods: Cross-sectional analysis of sleep characteristics in 3233 participants from the population-based CoLaus-HypnoLaus cohort (52.

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EEG slow waves, the hallmarks of NREM sleep are thought to be crucial for the regulation of several important processes, including learning, sensory disconnection and the removal of brain metabolic wastes. Animal research indicates that slow waves may involve complex interactions within and between cortical and subcortical structures. Conventional EEG in humans, however, has a low spatial resolution and is unable to accurately describe changes in the activity of subcortical and deep cortical structures.

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Functional connectivity (FC) metrics describe brain inter-regional interactions and may complement information provided by common power-based analyses. Here, we investigated whether the FC-metrics weighted Phase Lag Index (wPLI) and weighted Symbolic Mutual Information (wSMI) may unveil functional differences across four stages of vigilance-wakefulness (W), NREM-N2, NREM-N3, and REM sleep-with respect to each other and to power-based features. Moreover, we explored their possible contribution in identifying differences between stages characterized by distinct levels of consciousness (REM+W vs.

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Dreams are internally generated experiences that occur independently of current sensory input. Here we argue, based on cortical anatomy and function, that dream experiences are tightly related to the workings of a specific part of cortical pyramidal neurons, the apical integration zone (AIZ). The AIZ receives and processes contextual information from diverse sources and could constitute a major switch point for transitioning from externally to internally generated experiences such as dreams.

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Dreams are experiences that occur during sleep, while we are disconnected from the environment. Thanks to recent progress in neuroimaging techniques, it is now becoming possible to relate dream features to specific patterns of brain activity. Some conditions occurring in patients with neurological disorders, such as lucid dreams and parasomnias, not only have diagnostic value, but also offer a window into the dream process.

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It has been known for some time that the brain can react selectively to meaningful sensory stimuli during sleep. A recent study shows that this ability may be selectively suppressed during rapid eye movements of sleep.

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The slow waves of non-rapid eye movement (NREM) sleep reflect experience-dependent plasticity and play a direct role in the restorative functions of sleep. Importantly, slow waves behave as traveling waves, and their propagation is assumed to occur through cortico-cortical white matter connections. In this light, the corpus callosum (CC) may represent the main responsible for cross-hemispheric slow-wave propagation.

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Although excessive daytime sleepiness is commonly evaluated in clinical and research settings using the Epworth Sleepiness Scale, few studies have assessed the factors associated with its incidence in the general population. We prospectively investigated the predictors of incident and persistent excessive daytime sleepiness in 2,751 subjects (46.1% men, mean age 56.

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