Phasic Rapid Eye Movement Sleep Research Articles

Effect of Obstructive Sleep Apnea on Sleep Pattern and Blood Glucose Level in Type 2 Diabetes Patients

Introduction: Our physical, mental, and emotional well-being require normal sleep. Disturbances in sleep quality and quantity can result in metabolic disorders. Sleep fragmentation increases sympathetic activity which leads to decreased insulin sensitivity. Obstructive sleep apnea causes sleep fragmentation. That is why this study attempt is made to find the effect of obstructive sleep apnea on sleep pattern and blood glucose level in type 2 diabetes patients. Materials and Method: Depending on the severity of the Apnea-Hypopnea Index (AHI) recorded by polysomnography, each, volunteer were divided into two groups, a) AHI>10 groups, and b) AHI≤10 groups. Then the comparison of all the parameters between AHI>10 and AHI≤10 groups of diabetic participants was done. Results: In participants of AHI≤ 10 groups, Sleep efficiency%, Mean TBI SPo2%, sleep Stage III%, and REM% are significantly higher as compared to AHI>10 groups. In participants of the AHI>10 groups, sleep Stage I%, the score of ESS, and fasting blood glucose level are significantly higher as compared to AHI≤ 10 groups. Conclusions: Increasing AHI is associated with reduced sleep efficiency; a sleep stage of N3%, and a REM sleep phase, which lead to an increase in fasting blood glucose levels in the diabetic group.

Risk factors of sleep paralysis in a population of Polish students

BackgroundSleep paralysis (SP) is a transitional dissociative state associated with the REM sleep phase that affects approximately 28.3% of the student population during their lifetime. The reasons for the high prevalence of SP in the student population are not entirely clear. Research indicates possible influencing factors such as the intensification of anxiety symptoms, a tendency to worry, the presence of PTSD symptoms, and behavioral factors such as the consumption of psychoactive substances (caffeine, alcohol, nicotine), sleep deprivations and poor sleep hygiene. The study aimed to assess the prevalence of SP and determine the risk factors for the occurrence of SP in the population of Polish students.MethodsThe study used a battery online consisting of a set of questionnaires 1) a personal questionnaire, 2) the SP-EPQ, 3) the PCL −5, 4) the STAI-T, 5) the PSWQ. The questionnaire was sent via Facebook to 4500 randomly selected students from different universities in Poland. The questionnaire was completed by 2598 students. To unify the participant sample, people over 35 were excluded from the study (45 students). Ultimately, data from 2553 students were analyzed.ResultsA total of 33.14% of individuals experienced at least one episode of SP in their lives. The highest odds ratio for SP was associated with: the presence of three or more health problems (OR: 2.3; p = 0.002), the presence of any mental disorder (OR: 1.77; p = 0.002), including mood disorders (OR: 2.07; p = 0.002), suffering from at least one somatic disease (OR: 1.34; p = 0.002), a high level of anxiety as a constant personality trait (OR: 1.20; p = 0.035) and smoking (OR: 1.48; p = 0.0002), alcohol consumption (OR: 1.52; p < 0.0001), physical activity (OR: 1.31; p = 0.001).ConclusionsThe results of our research indicate that a large proportion of students experienced isolated sleep paralysis. Mental and somatic health problems and lifestyle factors were found to predispose individuals to this disorder. Due to the numerous risk factors for SP, it is necessary to conduct additional research to confirm the impact of these factors and to investigate the mechanisms of their influence on SP.

0262 Sleep-wake cycle circadian disruption after chronic alcohol intake in a rat model of anxiety

Abstract Introduction Alcohol intake can produce disruptions in sleep-wake cycle, including circadian alterations like phase shifts. Alcohol intake is increased in subjects with anxiety to diminish its symptoms. We have selectively bred two sublines from Sprague-Dawley rats that differs on its yawning frequency. The high-yawning (HY) rats have a mean of 20 yawns/h, whereas the low-yawning (LY) rats have only 2 yawns/hour. LY male rats had high anxiety-like behavior in standardized tests and high preference for alcohol intake. The aim of this study was to assess circadian disruption of sleep-wake cycle after chronic alcohol consumption. Methods We used 8 male rats from HY and LY at 3 months of age. All rats were kept in acrylic boxes with food pellets and purified water ad libitum under a light-dark cycle of 12:12 (lights on at 0700) and temperature of 21 ± 1 °C. All subjects were implanted for EEG, EMG and EOG recordings to characterize sleep-wake phases. A basal sleep-wake recording was obtained for 24 h. A second and third recording were made after a 7 days of alcohol administration as a single source of hydration (AL1) and a 3 week two-bottle choice alcohol preference protocol (AL2) were carried out. We used COSINOR analysis to determine phase and cycle alterations of sleep-wake circadian rhythm of all subjects. Results After alcohol intake, there was a significant difference only in the acrophases of awake periods (P&amp;lt;0.01) and slow wave sleep (SWS, P&amp;lt;0.001) in both AL1 and AL2 conditions for the HY subline, with a phase delay of 90 min for awake, 30 min for SWS and an advanced phase of 40 min for rapid eye movement sleep (REM) with respect to basal condition. In the case of LY subline, there was a significant difference only in SWS (P&amp;lt;0.001) and REM sleep (P&amp;lt;0.05) acrophases for both AL1 and AL2 conditions, with a phase delay of 7 h for wake, 40 min for SWS and 1 h for REM sleep. Conclusion It has been reported that alcohol disrupt circadian synchronization of the sleep-wake cycle, producing a general delay of SWS and REM sleep phases. Additionally, subjects with basal circadian disruptions are more susceptible to increase their intake of alcohol and other addictive drugs. So, LY male rats are an adequate model for higher susceptibility to alcohol intake. Support (If Any) Partially supported by PRONACES-CONACYT grant and VIEP-BUAP 2021 to CA in Neuroendocrinología (BUAP-CA-288). AFR is PhD on Physiological Sciences fellowship from CONACYT No. 926368

REM sleep and muscle atonia in brainstem stroke: A quantitative polysomnographic and lesion analysis study.

Important brainstem regions are involved in the regulation of rapid eye movement sleep. We hypothesized that brainstem stroke is associated with dysregulated rapid eye movement sleep and related muscle activity. We compared quantitative/qualitative polysomnography features of rapid eye movement sleep and muscle activity (any, phasic, tonic) between 15 patients with brainstem stroke (N=46 rapid eye movement periods), 16 patients with lacunar/non-brainstem stroke (N=40 rapid eye movement periods), 15 healthy controls (N=62 rapid eye movement periods), and patients with Parkinson's disease and polysomnography-confirmed rapid eye movement sleep behaviour disorder. Further, in the brainstem group, we performed a magnetic resonance imaging-based lesion overlap analysis. The mean ratio of muscle activity to rapid eye movement sleep epoch in the brainstem group ("any" muscle activity 0.09 ± 0.15; phasic muscle activity 0.08 ± 0.14) was significantly lower than in the lacunar group ("any" muscle activity 0.17 ± 0.2, p < 0.05; phasic muscle activity 0.16 ± 0.19, p < 0.05), and also lower than in the control group ("any" muscle activity 0.15 ± 0.17, p < 0.05). Magnetic resonance imaging-based lesion analysis indicated an area of maximum overlap in the medioventral pontine region for patients with reduced phasic muscle activity index. For all groups, mean values of muscle activity were significantly lower than in the patients with Parkinson's disease and polysomnography-confirmed REM sleep behaviour disorder group ("any" activity 0.51 ± 0.26, p < 0.0001 for all groups; phasic muscle activity 0.42 ± 0.21, p < 0.0001 for all groups). For the tonic muscle activity in the mentalis muscle, no significant differences were found between the groups. In the brainstem group, contrary to the lacunar and the control groups, "any" muscle activity index during rapid eye movement sleep was significantly reduced after the third rapid eye movement sleep phase. This study reports on the impact of brainstem stroke on rapid eye movement atonia features in a human cohort. Our findings highlight the important role of the human brainstem, in particular the medioventral pontine regions, in the regulation of phasic muscle activity during rapid eye movement sleep and the ultradian distribution of rapid eye movement-related muscle activity.

Effect of Fang's scalp acupuncture on perceived stress and sleep structure in insomnia patients: a randomized controlled trial

To compare the efficacy on insomnia between Fang 's scalp acupuncture combined with conventional acupuncture and the simple conventional acupuncture. A total of 66 patients with insomnia were randomly divided into an observation group (33 cases, 1 case dropped off) and a control group (33 cases, 2 cases dropped off). In the control group, the routine acupuncture therapy was applied to Shenmen (HT 7), Baihui (GV 20), Zhaohai (KI 6) and Sanyinjiao (SP 6), etc. Based on the treatment as the control group, Fang's scalp acupuncture therapy was supplemented at fuxiang tou, fuzang shangjiao, fuzang zhongjiao, siwei, etc. At these scalp points, the needles were inserted perpendicularly with flying needling technique and manipulated with trembling one. In either group, the treatment was given once daily, continuously for 2 weeks. Before and after treatment, separately, the score of Pittsburgh sleep quality index (PSQI) and the score of Chinese perceived stress scale (CPSS) were observed, as well as the parameters monitored by polysomnography, i.g. total sleep time (TST), sleep onset latency (SOL), wakefulness after the sleep onset (WASO), sleep efficiency (SE), the percentages of the time of rapid eye movement sleep phase (REM) and non-rapid eye movement sleep phase 1, 2, 3 and 4 in TST (REM%, N1%, N2%, N3%). The efficacy was compared between two groups. After treatment, the scores of each factor and the total scores of PSQI, as well as CPSS scores were all lower than those before treatment in the two groups (P<0.01, P<0.05); except the score for sleep quality, the score of each factor and the total score of PSQI, as well as CPSS score in the observation group were lower than those in the control group (P<0.01, P<0.05). After treatment, TST, SE%, REM% and N3% were increased and SOL, WASO, N1% were decreased as compared with before treatment in the two groups (P<0.01, P<0.05), and N2% in the observation group was decreased (P<0.01); SE%, REM% and N3% in the observation group were higher than the control group (P<0.05) and N1% and N2% were lower than the control group (P<0.05). The total effective rate was 93.8% (30/32) in the observation group, higher than 87.1% (27/31) in the control group (P<0.05). Fang 's scalp acupuncture, on the base of routine acupuncture, obviously improves the sleep quality and perceived stress and adjusts the sleep structure in the patients with insomnia.

Generalized EEG Slowing Across Phasic REM Sleep, Not Subjective RBD Severity, Predicts Neurodegeneration in Idiopathic RBD.

PurposeIdiopathic rapid eye movement sleep behavior disorder (iRBD) is the prodromal marker of α-synuclein degeneration with markedly high predictive value. We aim to evaluate the value of electroencephalography (EEG) data during rapid eye movement (REM) sleep and subjective RBD severity in predicting the conversion to neurodegenerative diseases in iRBD patients.MethodsAt the baseline, iRBD patients underwent clinical assessment and video-polysomnography (PSG). Relative spectral power for nine frequency bands during phasic and tonic REM sleep in three regions of interest, slow-to-fast ratios, clinical and PSG variables were estimated and compared between iRBD patients who converted to neurodegenerative diseases (iRBD-C) and iRBD patients who remained disease-free (iRBD-NC). Receiver operating characteristic (ROC) curves evaluated the predictive performance of slow-to-fast ratios, and subjective RBD severity as assessed with RBD Questionnaire-Hong Kong.ResultsTwenty-two (33.8%) patients eventually developed neurodegenerative diseases. The iRBD-C group showed shorter total sleep time (p < 0.001), lower stage 2 sleep percentage (p = 0.044), more periodic leg-movement-related arousal index (p = 0.004), increased tonic chin electromyelographic activity (p = 0.040) and higher REM density in the third REM episode (p = 0.034) than the iRBD-NC group. EEG spectral power analyses revealed that iRBD phenoconverters showed significantly higher delta and lower alpha power, especially in central and occipital regions during the phasic REM state compared to the iRBD-NC group. Significantly higher slow-to-fast ratios were observed in a more generalized way during the phasic state in the iRBD-C group compared to the iRBD-NC group. ROC analyses of the slowing ratio in occipital areas during phasic REM sleep yielded an area under the curve of 0.749 (p = 0.001), while no significant predictive value of subjective RBD severity was observed.ConclusionOur study shows that EEG slowing, especially in a more generalized manner during the phasic period, may be a promising marker in predicting phenoconversion in iRBD, rather than subjective RBD severity.

ПРОГНОСТИЧЕСКАЯ РОЛЬ ПАРАМЕТРОВ ДЫХАНИЯ В РАЗВИТИИ АРИТМИЙ У ПАЦИЕНТОВ С СИНДРОМОМ ОБСТРУКТИВНОГО НОЧНОГО АПНОЭ И ХРОНИЧЕСКОЙ СЕРДЕЧНОЙ НЕДОСТАТОЧНОСТЬЮ

Abstract. Obstructive sleep apnea syndrome (OSAS) is increasingly being considered as a factor associated with the development of nocturnal arrhythmias, as well as an increased risk of sudden cardiac death. The prevalence of OSA reaches 5-7% in the adult population. The prognostic role of pathological breathing patterns has not been sufficiently investigated, and therefore further study of the pathogenesis of arrhythmias for the subsequent intensification of therapeutic measures is promising. Aim of the Research. To study the prognostic significance of individual breathing parameters in different sleep phases for the development of atrial fibrillation and ventricular arrhythmias in patients with obstructive sleep apnea syndrome (OSAS) and chronic heart failure (CHF) with preserved ejection fraction (EF). Materials and methods. 86 men with moderate and severe OSAS (with an apnea/hypopnea index (AHI) &gt;15 per hour) were examined. To diagnose OSAS, all patients underwent a polysomnographic study of night sleep. The severity of obstructive respiratory disorders during sleep was assessed by the apnea/hypopnea index for the total period of sleeping. Using polysomnography, we additionally investigated the following parameters of respiratory disturbances during the night sleep period: index of obstructive apnea/hypopnea selectively in REM sleep (AHIobsREM); index of respiratory distress syndrome for the entire period of sleep (IRDS); index of respiratory distress syndrome in the REM sleep phase (IRDS REM); average saturation per night; desaturation index for the total period of sleep; desaturation index in REM sleep. The observation period was 12 months, during which the presence of atrial fibrillation paroxysms lasting more than 30 s and the development of high-grade ventricular arrhythmias (III-V class according to Ryan) were assessed. Results. In the course of the study, a number of breathing parameters during the night time sleep (IAHobs, IAHobsREM, IRDS, IRDS REM) significantly correlated with the development of the studied cardiac arrhythmias. The most significant prognostic role has been stated for obstructive sleep apnea registered in the REM sleep phase. Conclusion. Breathing parameters during nighttime sleeping (IAHobs, IAHobs REM, IRDS, IRDS REM), which characterize the severity of OSAS are independent predictors of the development of paroxysmal atrial fibrillation and high-grade ventricular extrasystole in patients with OSAS and CHF with preserved EF. The results obtained make it possible to use these sleep parameters in the future in stratifying the risk of arrhythmias and determining treatment tactics in this cohort of patients.

ТАКТИКА ПСИХОЛОГИЧЕСКОГО ОБСЛЕДОВАНИЯ И ПСИХОТЕРАПИИ НАРУШЕНИЙ СНА В ПЕРИОД ПАНДЕМИИ COVID-19

Due to the high prevalence of sleep disorders during the second and third waves, the question of the relationship between the incidence of coronavirus, acute respiratory distress syndrome and sleep is still open. The article describes for the first time the specifics of the phenomenon of COVID-SOMNIA or covid-associated sleep disorders, which includes a spectrum of changes in sleep from insomnia, restless legs syndrome to behavior disorders during the REM sleep phase. Various effects of COVID-19 on sleep disorders in patients have been shown. Different infections have different effects on the mental state and on a person’s sleep — these are sleep disorders caused by viral load. Specific clinical and psychological manifestations of covid-associated sleep disorders are described. For the first time in Russia, a model of the relationship between covid-associated anxiety, insomnia and suicidal thinking is presented. The psychological factors influencing the occurrence of the phenomenon of COVID-somnia in patients are systematized. It is shown that the risks of developing insomnia during the COVID-19 pandemic consist of the presence of a number of factors in the patient: tolerance to uncertainty, covid-associated anxiety, feelings of loneliness, the presence of symptoms of depression and anxiety earlier and at the moment. For clinical psychologists, the general tactics of psychological examination of an infected patient who has undergone COVID-19, who have post-ovoid syndrome in the presence of changes in the mental state and quality of sleep are described. In short, the protocols of remote cognitive behavioral therapy of anxiety associated with the COVID-19 pandemic are based on a psychological model of health anxiety and hypochondria (somatosensory amlification). It is recommended that we use cognitive refocusing therapy for insomnia (cognitive refocusing treatment) and a protocol for short-term remote cognitive behavioral therapy of anxiety associated with the COVID-19 pandemic in everyday clinical practice.

How Useful is the Electroencephalogram (EEG) as a Tool for Signaling Cognitive Decline in Parkinson’s Disease?

Parkinson’s disease (PD) is a common neurological disease. Due to its chronic and progressive character, it is marked by a slow depletion in dopaminergic transmission in the basal ganglia. Since its original description, new findings have hatched; making it, by many specialists, as a systemic disease that starts with hyposmia, changes in the REM sleep phase and intestinal constipation, years before the motor manifestations [1].

Hippocampus-retrosplenial cortex interaction is increased during phasic REM and contributes to memory consolidation

Hippocampal (HPC) theta oscillation during post-training rapid eye movement (REM) sleep supports spatial learning. Theta also modulates neuronal and oscillatory activity in the retrosplenial cortex (RSC) during REM sleep. To investigate the relevance of theta-driven interaction between these two regions to memory consolidation, we computed the Granger causality within theta range on electrophysiological data recorded in freely behaving rats during REM sleep, both before and after contextual fear conditioning. We found a training-induced modulation of causality between HPC and RSC that was correlated with memory retrieval 24 h later. Retrieval was proportional to the change in the relative influence RSC exerted upon HPC theta oscillation. Importantly, causality peaked during theta acceleration, in synchrony with phasic REM sleep. Altogether, these results support a role for phasic REM sleep in hippocampo-cortical memory consolidation and suggest that causality modulation between RSC and HPC during REM sleep plays a functional role in that phenomenon.

Event-related potentials in insomnia reflect altered perception of sleep.

Insomnia is defined by the subjective complaint of poor sleep as well as daytime impairments. Since polysomnography (PSG) typically shows only modest sleep impairment, some still unidentified property of sleep, not mirrored in PSG, may be modified in insomnia.One possible mechanistic hypothesis is that insomnia patients may be more sensitive to inevitably occurring internal or external stimuli during the night, causing brief sleep disruptions then perceived as wake time. Auditory event-related potentials (ERP) to low intensity (50 dB SPL) synthesized guitar tones played continuously throughout two nights of polysomnographically registered sleep were obtained in fifty patients with insomnia disorder (ID, without comorbidities) and 50 age- and sex-matched good sleeper controls (GSC) for each sleep stage and NREM/REM cycle. Phasic and tonic REM were treated as separate stages. Latencies and amplitudes of components P1, N1 and P2 were measured and analyzed by multivariate repeated-measures ANCOVA including effects of group, night, cycle, and age. ID showed reduced P2 amplitudes relative to GSC specifically in phasic REM sleep. The same reduction also correlated with the amount of sleep misperception across groups. Independent component analysis showed a frontal negativity to contribute most to this group difference. The present finding can be interpreted as increased mismatch negativity (MMN) in ID, reflecting automated detection of change in the auditory system and a concomitant orienting response. Specifically phasic REM sleep appears to be vulnerable to sensory afferences in ID patients, possibly contributing to the perception of being awake. Short name "PERSLEEP 2," URL https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00008965, Registration DRKS00008965.

Dopaminergic- and cholinergic-inputs from substantia nigra and pedunculo-pontine tegmentum, respectively, converge in amygdala to modulate rapid eye movement sleep in rats

Dreams appear intermittently during phasic rapid eye movement sleep (REMS). Although reasonable progress has been made about neuro-physio-pharmacological mechanism of appearance of REMS, appearance of dreams is a mystery. Isolated studies have reported that substantia nigra (SN) withdraws inhibition from pedunculo-pontine tegmentum (PPT) acetylcholine (ACh)-ergic REM-ON neurons to trigger REMS; some REM-ON neurons become phasically active during REMS; amygdala (Amyg), a limbic structure associated with emotions, may be related with dreaming like state; Amyg receives projections from both SN-Dopamine (DA)-ergic and PPT-ACh-ergic neurons. Collating these isolated findings, we proposed that on the background of REMS, SN-DA-ergic and PPT-ACh-ergic inputs phasically activate Amyg-neurons to manifest dreams. In the absence of better criteria, we recorded electrophysiological characteristics of REMS as the closest objective read-out for dreams in surgically prepared, chronic, freely moving rats. Microinjection of either DA-ergic or ACh-ergic agonist [Quinpirole (Qnp) or Carbachol (Carb)] bilaterally into Amyg increased, while antagonists [Haloperidol (Hal) or Scopolamine (Scop)] reduced REMS. Electrical stimulation of either bilateral SN or PPT increased REMS, which however, was prevented when stimulated in presence of Hal or Scop, respectively into the Amyg. These findings confirm and support our contention that SN-DA-ergic and PPT-ACh-ergic inputs integrate in Amyg for REMS regulation. Further, subject to confirmation in humans, we propose that on the background of REMS, some phasic PPT-ACh-ergic-REM-ON neurons intermittently trigger some neurons in Amyg, the area known to be associated with memory and emotions, causing intermittent appearance of REMS-associated dreams and in REMS behavior disorder.

REM Sleep Microstates in the Human Anterior Thalamus.

Rapid eye movement (REM) sleep is an elusive neural state that is associated with a variety of functions from physiological regulatory mechanisms to complex cognitive processing. REM periods consist of the alternation of phasic and tonic REM microstates that differ in spontaneous and evoked neural activity. Although previous studies indicate, that cortical and thalamocortical activity differs across phasic and tonic microstates, the characterization of neural activity, particularly in subcortical structures that are critical in the initiation and maintenance of REM sleep is still limited in humans. Here, we examined electric activity patterns of the anterior nuclei of the thalamus as well as their functional connectivity with scalp EEG recordings during REM microstates and wakefulness in a group of epilepsy patients (N = 12, 7 females). Anterothalamic local field potentials (LFPs) showed increased high-α and β frequency power in tonic compared with phasic REM, emerging as an intermediate state between phasic REM and wakefulness. Moreover, we observed increased thalamocortical synchronization in phasic compared with tonic REM sleep, especially in the slow and fast frequency ranges. Wake-like activity in tonic REM sleep may index the regulation of arousal and vigilance facilitating environmental alertness. On the other hand, increased thalamocortical synchronization may reflect the intrinsic activity of frontolimbic networks supporting emotional and memory processes during phasic REM sleep. In sum, our findings highlight that the heterogeneity of phasic and tonic REM sleep is not limited to cortical activity, but is also manifested by anterothalamic LFPs and thalamocortical synchronization.SIGNIFICANCE STATEMENT REM sleep is a heterogeneous sleep state that features the alternation of two microstates, phasic and tonic rapid eye movement (REM). These states differ in sensory processing, awakening thresholds, and cortical activity. Nevertheless, the characterization of these microstates, particularly in subcortical structures is still limited in humans. We had the unique opportunity to examine electric activity patterns of the anterior nuclei of the thalamus (ANTs) as well as their functional connectivity with scalp EEG recordings during REM microstates and wakefulness. Our findings show that the heterogeneity of phasic and tonic REM sleep is not limited to cortical activity, but is also manifested in the level of the thalamus and thalamocortical networks.

SLEEP DISORDERS DURING THE COVID-19 PANDEMIC: SPECIFICS, EXAMINATION AND PSYCHOTHERAPY

The article describes the phenomenon of COVID-somnia, which includes a specific spectrum of changes in sleep from insomnia to behavior disorder during the REM sleep phase. Various effects of COVID-19 on sleep disorders have been shown. Manifestations of covid-associated sleep disorders (chronic insomnia, restless legs syndrome) are described. A model of the relationship between covid-associated anxiety, insomnia and suicidal thinking is presented. The psychological factors influencing the phenomenon of COVID-somnia are systematized. The predicted insomnia during the COVID-19 pandemic consists of the presence of intolerance to uncertainty, covid-associated anxiety, feelings of loneliness, the presence of symptoms of depression and anxiety. The algorithm of screening assessment of the patient's condition during the COVID-19 pandemic and the specifics of a complete psychological examination of the COVID-somnia phenomenon in the patient are described for the first time. A protocol for short-term remote cognitive behavioral therapy of anxiety associated with the COVID-19 pandemic by Anderson to minimize chronic insomnia is presented.

A high-density electroencephalography study reveals abnormal sleep homeostasis in patients with rapid eye movement sleep behavior disorder

Rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by disrupting motor enactments during REM sleep, but also cognitive impairments across several domains. In addition to REM sleep abnormalities, we hypothesized that RBD patients may also display EEG abnormalities during NREM sleep. We collected all-night recordings with 256-channel high-density EEG in nine RBD patients, predominantly early-onset medicated individuals, nine sex- and age- matched healthy controls, and nine additional controls with matched medications and comorbidities. Power spectra in delta to gamma frequency bands were compared during both REM and NREM sleep, between phasic and tonic REM sleep, and between the first versus last cycle of NREM sleep. Controls, but not RBD patients, displayed a decrease in beta power during phasic compared to tonic REM sleep. Compared to controls, RBD patients displayed a reduced decline in SWA from early to late NREM sleep. Overnight changes in the distribution of the amplitude of slow waves were also reduced in RBD patients. Without suppression of beta rhythms during phasic REM sleep, RBD patients might demonstrate heightened cortical arousal, favoring the emergence of behavioral episodes. A blunted difference between REM sleep sub-stages may constitute a sensitive biomarker for RBD. Moreover, reduced overnight decline in SWA suggests a reduced capacity for synaptic plasticity in RBD patients, which may favor progression towards neurodegenerative diseases.

Tracking Eye Movements During Sleep in Mice.

Eye movement is not only for adjusting the visual field and maintaining the stability of visual information on the retina, but also provides an external manifestation of the cognitive status of the brain. Recent studies showed similarity in eye movement patterns between wakefulness and rapid eye movement (REM) sleep, indicating that the brain status of REM sleep likely resembles that of awake status. REM sleep in humans could be divided into phasic REM and tonic REM sleep according to the difference in eye movement frequencies. Mice are the most commonly used animal model for studying neuronal and molecular mechanisms underlying sleep. However, there was a lack of details for eye movement patterns during REM sleep, hence it remains unknown whether REM sleep can be further divided into different stages in mice. Here we developed a device combining electroencephalogram (EEG), electromyogram (EMG) as well as eye movements recording in mice to study the eye movement patterns during sleep. We implanted a magnet beneath the conjunctiva of eye and tracked eye movements using a magnetic sensor. The magnetic signals showed strong correlation with video-oculography in head-fixed mice, indicating that the magnetic signals reflect the direction and magnitude of eye movement. We also found that the magnet implanted beneath the conjunctiva exhibited good biocompatibility. Finally, we examined eye movement in sleep–wake cycle, and discriminated tonic REM and phasic REM according to the frequency of eye movements, finding that compared to tonic REM, phasic REM exhibited higher oscillation power at 0.50 Hz, and lower oscillation power at 1.50–7.25 Hz and 9.50–12.00 Hz. Our device allowed to simultaneously record EEG, EMG, and eye movements during sleep and wakefulness, providing a convenient and high temporal-spatial resolution tool for studying eye movements in sleep and other researches in mice.

Sleep Disorders During the Covid-19 Pandemic: Specifics and Psychological Diagnostic

The article describes the phenomenon of COVID-somnia, which includes a specific spectrum of changes in sleep from insomnia to behavior disorder during the REM sleep phase. Different effects of COVID-19 on sleep disorders have been shown. Manifestations of covid-associated sleep disorders (chronic insomnia, restless legs syndrome) are described. A model of the relationship between covid-associated anxiety, insomnia, and suicidal thinking is presented. The psychological factors influencing the phenomenon of COVID-somnia are systematized. Predicted insomnia during the COVID-19 pandemic consists of the presence of intolerance to uncertainty, covid-associated anxiety, feelings of loneliness, the presence of symptoms of depression and anxiety. The algorithm of screening assessment of the patient’s condition during the COVID-19 pandemic and the specifics of a complete psychological examination of the COVID-somnia phenomenon in the patient are described for the first time. The protocol of short-term remote cognitive-behavioral therapy of anxiety associated with the COVID-19 pandemic by E. M. Anderson to minimize chronic insomnia is presented.

Objective sleep data as predictors of cognitive decline in dementia with Lewy Bodies and Parkinson's disease

IntroductionParkinson's disease (PD) and Dementia with Lewy Bodies (DLB) prognosis depends on cognitive function evolution. Sleep disorders, as objectivated by polysomnography (PSG), are intimately connected with PD and DLB pathophysiology, but have seldomly been used to predict cognitive decline. Methods20 DLB and 49 PD patients underwent one-night in-lab video-PSG. Sleep variables were defined, including REM sleep motor events, Tonic and phasic REM sleep muscular tone and RBD diagnosis. Cognitive state (assessed with the Global Deterioration Scale (GDS) was collected from case files for 6 months intervals, for a maximum period of 3.5 years or until death/drop-out.). The relation between PSG data at baseline and variation of GDS scores over time was tested with mixed linear regression analysis. ResultsGDS scores were higher in DLB, than in PD. We confirmed significant cognitive decline in both disorders, but no significant differences in progression between them. There were no significant interactions between PSG data and GDS variation for the entire group and DLB separately. In PD patients, there was a significant interaction between RBD diagnosis and tonic excessive muscular tone and GDS increase. ConclusionOur data suggests that PSG data can be useful in predicting cognitive decline in PD but not in DLB patients. In PD patients, an RBD diagnosis is predictive of cognitive deterioration, confirming the notion that this non-motor symptom relates to a malignant sub-type. Tonic excessive muscular activity, but not other RBD features, had predictive value in this group, pointing to a specific relation with the disease pathophysiology.

Predictive value of respiratory parameters in patients with obstructive sleep apnea and chronic heart failure with preserved ejection fraction

Aim. To study individual functional parameters of respiration in different phases of sleep in patients with obstructive sleep apnea (OSA) and chronic heart failure with preserved ejection fraction (HFpEF) and to assess their effect on the clinical course of the disease.&#x0D; Methods. The study included 86 men with OSA [with an apnea-hypopnea index (AHI) 15 per hour]. Upon inclusion in the study, all patients underwent a polysomnographic study and echocardiography, the level of brain natriuretic peptide (NT-proBNP) was determined, a six-minute walk test was performed. After 12 months of prospective observation, the patients were divided into 2 groups according to the clinical course of chronic heart failure: with unfavorable (n=33) and favorable (n=53) clinical course. The prognostic significance of the studied parameters of respiration to the course of the disease was assessed by using logistic and linear regression.&#x0D; Results. A significant role of the following respiratory parameters as predictors of chronic heart failure progression was established: obstructive apnea-hypopnea index for the entire night sleep [odds ratio (OR) 1.04, p=0.002] and in the phase of rapid eye movement sleep (REM) (ОR 1.24, p=0.001); the index of respiratory disorders for the entire sleep period (ОR 1.06, p=0.044) and in REM sleep phase (ОR 1.25, p=0.003). For hospital readmission, the predictive role was determined for obstructive apnea/hypopnea index for REM phase (ОR 1.07, p=0.044) and index of respiratory disorders for REM phase (ОR 1.13, p=0.040).&#x0D; Conclusion. The prognostic value of the obstructive apnea-hypopnea index and the index of respiratory disorders for the entire night sleep and in the phase of REM sleep was revealed for patients with OSA and chronic heart failure with preserved ejection fraction, which allows considering these parameters as independent predictors of an unfavorable clinical course in this group of patients.

Unaltered EEG spectral power and functional connectivity in REM microstates in frequent nightmare recallers: are nightmares really a REM parasomnia?

BackgroundFrequent nightmares show signs of hyperarousal in NREM sleep. Nevertheless, idiopathic nightmare disorder is considered a REM parasomnia, but the pathophysiology of REM sleep in relation to frequent nightmares is controversial. Cortical oscillatory activity in REM sleep is largely modulated by phasic and tonic REM periods and seems to be linked to different functions and dysfunctions of REM sleep. Here, we examined cortical activity and functional synchronization in frequent nightmare recallers and healthy controls, during phasic and tonic REM. MethodsFrequent nightmare recallers (N = 22) and healthy controls (N = 22) matched for high dream recall spent two nights in the laboratory. Phasic and tonic REM periods from the second nights' recordings were selected to examine differences in EEG spectral power and weighted phase lag index (WPLI) across groups and REM states. ResultsPhasic REM showed increased power and synchronization in delta and gamma frequency bands, whereas tonic REM featured increased power and synchronization in the alpha and beta bands. In the theta band, power was higher during tonic, and synchronization was higher during phasic REM sleep. No differences across nightmare and control participants or patterns representing interactions between the groups and REM microstates emerged. ConclusionsOur findings do not support the idea that abnormal REM sleep power and synchronization play a role in the pathophysiology of frequent nightmares. Altered REM sleep in nightmare disorder could have been confounded with comorbid pathologies and increased dream recall, or might be linked to more specific state factors (nightmare episodes).