Changes in EEG permutation entropy in the evening and in the transition from wake to sleep

Abstract Quantifying the complexity of the EEG signal during prolonged wakefulness and during sleep is gaining interest as an additional mean to characterize the mechanisms associated with sleep and wakefulness regulation. Here, we characterized how EEG complexity, as indexed by Multiscale Permutation Entropy (MSPE), changed progressively in the evening prior to light off and during the transition from wakefulness to sleep. We further explored whether MSPE was able to discriminate between wakefulness and sleep around sleep onset and whether MSPE changes were correlated with spectral measures of the EEG related to sleep need during concomitant wakefulness (theta power—Ptheta: 4–8 Hz). To address these questions, we took advantage of large datasets of several hundred of ambulatory EEG recordings of individual of both sexes aged 25–101 years. Results show that MSPE significantly decreases before light off (i.e. before sleep time) and in the transition from wakefulness to sleep onset. Furthermore, MSPE allows for an excellent discrimination between pre-sleep wakefulness and early sleep. Finally, we show that MSPE is correlated with concomitant Ptheta. Yet, the direction of the latter correlation changed from before light-off to the transition to sleep. Given the association between EEG complexity and consciousness, MSPE may track efficiently putative changes in consciousness preceding sleep onset. An MSPE stands as a comprehensive measure that is not limited to a given frequency band and reflects a progressive change brain state associated with sleep and wakefulness regulation. It may be an effective mean to detect when the brain is in a state close to sleep onset.

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Comparative Analysis of the Permutation and Multiscale Entropies for Quantification of the Brain Signal Variability in Naturalistic Scenarios

Brain Sciences ◽

10.3390/brainsci10080527 ◽

2020 ◽

Vol 10 (8) ◽

pp. 527

Author(s):

Soheil Keshmiri

Keyword(s):

Brain Function ◽

Human Subjects ◽

Multiscale Entropy ◽

Permutation Entropy ◽

Affective States ◽

Affective Stimuli ◽

Eeg Recordings ◽

The One ◽

The Brain ◽

Signal Variability

As alternative entropy estimators, multiscale entropy (MSE) and permutation entropy (PE) are utilized for quantification of the brain function and its signal variability. In this context, their applications are primarily focused on two specific domains: (1) the effect of brain pathology on its function (2) the study of altered states of consciousness. As a result, there is a paucity of research on applicability of these measures in more naturalistic scenarios. In addition, the utility of these measures for quantification of the brain function and with respect to its signal entropy is not well studied. These shortcomings limit the interpretability of the measures when used for quantification of the brain signal entropy. The present study addresses these limitations by comparing MSE and PE with entropy of human subjects’ EEG recordings, who watched short movie clips with negative, neutral, and positive content. The contribution of the present study is threefold. First, it identifies a significant anti-correlation between MSE and entropy. In this regard, it also verifies that such an anti-correlation is stronger in the case of negative rather than positive or neutral affects. Second, it finds that MSE significantly differentiates between these three affective states. Third, it observes that the use of PE does not warrant such significant differences. These results highlight the level of association between brain’s entropy in response to affective stimuli on the one hand and its quantification in terms of MSE and PE on the other hand. This, in turn, allows for more informed conclusions on the utility of MSE and PE for the study and analysis of the brain signal variability in naturalistic scenarios.

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Dynamics of Epileptiform Discharges Induced by Transcranial Magnetic Stimulation in Genetic Generalized Epilepsy

International Journal of Neural Systems ◽

10.1142/s012906571750037x ◽

2017 ◽

Vol 27 (07) ◽

pp. 1750037 ◽

Cited By ~ 9

Author(s):

Dimitris Kugiumtzis ◽

Christos Koutlis ◽

Alkiviadis Tsimpiris ◽

Vasilios K. Kimiskidis

Keyword(s):

Transcranial Magnetic Stimulation ◽

Magnetic Stimulation ◽

Brain Connectivity ◽

Effective Connectivity ◽

Brain Network ◽

Brain State ◽

Epileptiform Discharges ◽

Eeg Recordings ◽

Generalized Epilepsy ◽

The Brain

Objective: In patients with Genetic Generalized Epilepsy (GGE), transcranial magnetic stimulation (TMS) can induce epileptiform discharges (EDs) of varying duration. We hypothesized that (a) the ED duration is determined by the dynamic states of critical network nodes (brain areas) at the early post-TMS period, and (b) brain connectivity changes before, during and after the ED, as well as within the ED. Methods: EEG recordings from two GGE patients were analyzed. For hypothesis (a), the characteristics of the brain dynamics at the early ED stage are measured with univariate and multivariate EEG measures and the dependence of the ED duration on these measures is evaluated. For hypothesis (b), effective connectivity measures are combined with network indices so as to quantify the brain network characteristics and identify changes in brain connectivity. Results: A number of measures combined with specific channels computed on the first EEG segment post-TMS correlate with the ED duration. In addition, brain connectivity is altered from pre-ED to ED and post-ED and statistically significant changes were also detected across stages within the ED. Conclusion: ED duration is not purely stochastic, but depends on the dynamics of the post-TMS brain state. The brain network dynamics is significantly altered in the course of EDs.

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Low Doses of Melatonin Promote Sleep Onset and Maintenance in Older People—An Update

US Neurology ◽

10.17925/usn.2014.10.02.117 ◽

2014 ◽

Vol 10 (02) ◽

pp. 117 ◽

Cited By ~ 4

Author(s):

Richard J Wurtman ◽

Keyword(s):

Side Effects ◽

Older People ◽

Total Sleep Time ◽

Sleep Onset ◽

Sleep Time ◽

Low Doses ◽

Plasma Melatonin ◽

High Doses ◽

The Brain ◽

Very High

Plasma melatonin levels in young adults are about 10-fold higher during the night than during daylight hours, and these high levels promote both the onset of sleep at bedtime and the speedy resumption of sleep after premature nocturnal awakenings. With aging, melatonins nocturnal secretion from the pineal gland declines, as do plasma melatonin levels, total sleep time, and sleep efficiency. A very small dose (0.3 mg) of melatonin is usually sufficient to restore nighttime plasma melatonin levels to those characteristic of young people, and to accelerate the resumption of sleep after premature awakenings. The much larger doses that are marketed can produce side effects that are not observed when the melatonin in the plasma derives solely from its secretion by the pineal. Very high doses may also desensitize melatonins receptors in the brain, subsequently diminishing melatonins efficacy in promoting sleep. This article updates an earlier summary (Richard J Wurtman, Use of melatonin to promote sleep in older people,US Neurology, 2012;8(1):101) of melatonins utility in promoting sleep among older people.

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Brain Rhythms

MEG-EEG Primer ◽

10.1093/med/9780190497774.003.0010 ◽

2017 ◽

pp. 165-188

Author(s):

Riitta Hari ◽

Aina Puce

Keyword(s):

Auditory Cortex ◽

Eeg Signal ◽

Gamma Delta ◽

Brain Rhythms ◽

Slow Oscillations ◽

Timing Information ◽

Sensory Motor ◽

Signal Changes ◽

Eeg Recordings ◽

The Brain

This chapter provides examples of studies of MEG and EEG brain rhythms that have considerably increased understanding of the human brain’s sensory, motor, cognitive, and affective functions. Parieto-occipital alpha, Rolandic mu and auditory-cortex tau rhythms, as well as more widely spread beta, theta, gamma, delta and ultra-slow oscillations are described. Additionally, MEG/EEG signal changes that accompany different vigilance states, such as drowsiness and sleep, as well as anesthesia, are discussed. We emphasize the importance of timing information that MEG and EEG recordings, including the brain rhythms, provide. In this and subsequent chapters, we rely somewhat on our own studies and experiences, so as to give educational insights from the pitfalls and challenges we ourselves have experienced.

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Epileptic Seizures Prediction Using Deep Learning Methods on EEG Recordings

Webology ◽

10.14704/web/v17i2/web17063 ◽

2020 ◽

Vol 17 (2) ◽

pp. 717-734

Author(s):

G. Maragatham ◽

T. Kirthiga Devi ◽

P. Savaridassan ◽

Sachin Garg

Keyword(s):

Brain Activity ◽

Epileptic Seizures ◽

Eeg Signal ◽

Severe Damage ◽

Unusual Behavior ◽

Appropriate Care ◽

Eeg Recordings ◽

American Society ◽

The Brain ◽

Abnormal Brain

Epilepsy is a neurological disorder that disturbs the brain and causes abnormal brain activity. It results in loss of awareness in some cases and unusual behavior and sensations. In this regard, if the seizures could be identified in its earlier stages then the patient can be provided appropriate care and treatment in time and prevent any severe damage to the patient as a whole. In this paper, we try to detect epilepsy using the EEG Signal Recordings and classify them using pre-trained CNN models between preictal and interictal classes. For this we are advocating the use of American Society for Epilepsy Dataset. The focus is on detecting the epilepsy pattern from the EEG recordings in a timely and accurate manner.

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Multi-Scale Permutation Entropy: A Potential Measure for the Impact of Sleep Medication on Brain Dynamics of Patients with Insomnia

Entropy ◽

10.3390/e23091101 ◽

2021 ◽

Vol 23 (9) ◽

pp. 1101

Author(s):

Yanping Guo ◽

Yingying Chen ◽

Qianru Yang ◽

Fengzhen Hou ◽

Xinyu Liu ◽

...

Keyword(s):

Sleep Stage ◽

Sleep Onset ◽

Permutation Entropy ◽

Brain Dynamics ◽

Multi Scale ◽

Sleep Medication ◽

Alternative Approach ◽

Eeg Recordings ◽

Sleep Transition ◽

The Impact

Insomnia is a common sleep disorder that is closely associated with the occurrence and deterioration of cardiovascular disease, depression and other diseases. The evaluation of pharmacological treatments for insomnia brings significant clinical implications. In this study, a total of 20 patients with mild insomnia and 75 healthy subjects as controls (HC) were included to explore alterations of electroencephalogram (EEG) complexity associated with insomnia and its pharmacological treatment by using multi-scale permutation entropy (MPE). All participants were recorded for two nights of polysomnography (PSG). The patients with mild insomnia received a placebo on the first night (Placebo) and temazepam on the second night (Temazepam), while the HCs had no sleep-related medication intake for either night. EEG recordings from each night were extracted and analyzed using MPE. The results showed that MPE decreased significantly from pre-lights-off to the period during sleep transition and then to the period after sleep onset, and also during the deepening of sleep stage in the HC group. Furthermore, results from the insomnia subjects showed that MPE values were significantly lower for the Temazepam night compared to MPE values for the Placebo night. Moreover, MPE values for the Temazepam night showed no correlation with age or gender. Our results indicated that EEG complexity, measured by MPE, may be utilized as an alternative approach to measure the impact of sleep medication on brain dynamics.

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Complexity Measures of Brain Electrophysiological Activity

Journal of Psychophysiology ◽

10.1027/0269-8803/a000024 ◽

2010 ◽

Vol 24 (2) ◽

pp. 131-135 ◽

Cited By ~ 5

Author(s):

Włodzimierz Klonowski ◽

Pawel Stepien ◽

Robert Stepien

Keyword(s):

Brain Activity ◽

Deterministic Chaos ◽

Epileptic Seizures ◽

Eeg Signal ◽

Eeg Signals ◽

Complexity Measures ◽

Electrophysiological Activity ◽

Signal Complexity ◽

Physiological Sleep ◽

The Brain

Over 20 years ago, Watt and Hameroff (1987 ) suggested that consciousness may be described as a manifestation of deterministic chaos in the brain/mind. To analyze EEG-signal complexity, we used Higuchi’s fractal dimension in time domain and symbolic analysis methods. Our results of analysis of EEG-signals under anesthesia, during physiological sleep, and during epileptic seizures lead to a conclusion similar to that of Watt and Hameroff: Brain activity, measured by complexity of the EEG-signal, diminishes (becomes less chaotic) when consciousness is being “switched off”. So, consciousness may be described as a manifestation of deterministic chaos in the brain/mind.

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Conditional Entropy: A Potential Digital Marker for Stress

Entropy ◽

10.3390/e23030286 ◽

2021 ◽

Vol 23 (3) ◽

pp. 286

Author(s):

Soheil Keshmiri

Keyword(s):

Resting State ◽

Nearest Neighbor ◽

Brain Activity ◽

Solution Concept ◽

Conditional Entropy ◽

K Nearest Neighbor ◽

Brain Response ◽

Substantial Progress ◽

Eeg Recordings ◽

The Brain

Recent decades have witnessed a substantial progress in the utilization of brain activity for the identification of stress digital markers. In particular, the success of entropic measures for this purpose is very appealing, considering (1) their suitability for capturing both linear and non-linear characteristics of brain activity recordings and (2) their direct association with the brain signal variability. These findings rely on external stimuli to induce the brain stress response. On the other hand, research suggests that the use of different types of experimentally induced psychological and physical stressors could potentially yield differential impacts on the brain response to stress and therefore should be dissociated from more general patterns. The present study takes a step toward addressing this issue by introducing conditional entropy (CE) as a potential electroencephalography (EEG)-based resting-state digital marker of stress. For this purpose, we use the resting-state multi-channel EEG recordings of 20 individuals whose responses to stress-related questionnaires show significantly higher and lower level of stress. Through the application of representational similarity analysis (RSA) and K-nearest-neighbor (KNN) classification, we verify the potential that the use of CE can offer to the solution concept of finding an effective digital marker for stress.

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Failure of the Brain Glucagon-Like Peptide-1-Mediated Control of Intestinal Redox Homeostasis in a Rat Model of Sporadic Alzheimer’s Disease

Antioxidants ◽

10.3390/antiox10071118 ◽

2021 ◽

Vol 10 (7) ◽

pp. 1118

Author(s):

Jan Homolak ◽

Ana Babic Perhoc ◽

Ana Knezovic ◽

Jelena Osmanovic Barilar ◽

Melita Salkovic-Petrisic

Keyword(s):

Oxidative Stress ◽

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Rat Model ◽

Redox Homeostasis ◽

Brain State ◽

Gastrointestinal Hormone ◽

Glucagon Like Peptide ◽

Glucagon Like Peptide 1 ◽

The Brain

The gastrointestinal system may be involved in the etiopathogenesis of the insulin-resistant brain state (IRBS) and Alzheimer’s disease (AD). Gastrointestinal hormone glucagon-like peptide-1 (GLP-1) is being explored as a potential therapy as activation of brain GLP-1 receptors (GLP-1R) exerts neuroprotection and controls peripheral metabolism. Intracerebroventricular administration of streptozotocin (STZ-icv) is used to model IRBS and GLP-1 dyshomeostasis seems to be involved in the development of neuropathological changes. The aim was to explore (i) gastrointestinal homeostasis in the STZ-icv model (ii) assess whether the brain GLP-1 is involved in the regulation of gastrointestinal redox homeostasis and (iii) analyze whether brain-gut GLP-1 axis is functional in the STZ-icv animals. Acute intracerebroventricular treatment with exendin-3(9-39)amide was used for pharmacological inhibition of brain GLP-1R in the control and STZ-icv rats, and oxidative stress was assessed in plasma, duodenum and ileum. Acute inhibition of brain GLP-1R increased plasma oxidative stress. TBARS were increased, and low molecular weight thiols (LMWT), protein sulfhydryls (SH), and superoxide dismutase (SOD) were decreased in the duodenum, but not in the ileum of the controls. In the STZ-icv, TBARS and CAT were increased, LMWT and SH were decreased at baseline, and no further increment of oxidative stress was observed upon central GLP-1R inhibition. The presented results indicate that (i) oxidative stress is increased in the duodenum of the STZ-icv rat model of AD, (ii) brain GLP-1R signaling is involved in systemic redox regulation, (iii) brain-gut GLP-1 axis regulates duodenal, but not ileal redox homeostasis, and iv) brain-gut GLP-1 axis is dysfunctional in the STZ-icv model.

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0004 TS-142: A Novel and Potent Dual Orexin Receptor Antagonist with Sleep-Promoting Effects in Rats

SLEEP ◽

10.1093/sleep/zsaa056.003 ◽

2020 ◽

Vol 43 (Supplement_1) ◽

pp. A2-A2

Author(s):

D Kambe ◽

H Hikichi ◽

Y Tokumaru ◽

M Ohmichi ◽

Y Konno ◽

...

Keyword(s):

Receptor Antagonist ◽

Half Life ◽

Sleep Onset ◽

Sleep Time ◽

Sleep Onset Latency ◽

Orexin A ◽

Pharmacokinetic Profiles ◽

Orexin Receptors ◽

Elimination Half ◽

Emg Electrodes

Abstract Introduction The orexin system plays a pivotal role in regulating sleep and wakefulness, thus, orexin receptors (OX1 and OX2 receptors) have gained much attention as promising therapeutic targets for the treatment of insomnia. We synthesized a novel and potent dual orexin receptor antagonist (DORA), ORN0829 (investigation code name as TS-142), which was designed to have short-acting effects. Here we report pharmacological and pharmacokinetic profiles of ORN0829 in rats. Methods The antagonistic activities of ORN0829 were assessed using calcium mobilization assays. Ala-orexin A-induced [Ca2+]i response was measured with CHO-K1 cells stably expressing human/rat orexin receptor. Rats implanted the EEG/EMG electrodes were orally administrated ORN0829 at doses of 1, 3 or 10 mg/kg at the dark onset and sleep-wake stages were inspected visually. In addition, pharmacokinetic profiles of ORN0829 were investigated in rats. Results ORN0829 inhibited Ala-orexin A-increased [Ca2+]i response with a Kb of 0.67/0.44 nmol/L (for human/rat OX1 receptor), and with a Kb of 0.84/0.80 nmol/L (for human/rat OX2 receptor), respectively, indicating that ORN0829 is a potent DORA with no species differences. ORN0829 dose-dependently increased total sleep time and reduced sleep onset latency at doses of 1, 3 and 10 mg/kg. Importantly, the ORN0829 levels in plasma and cerebrospinal fluid rapidly reached a maximum concentration, and decreased with an elimination half-life of less than 1 h. Conclusion The present study indicates that ORN0829 is a novel and potent DORA with sleep-promoting effects, and that it exhibits ideal pharmacokinetic profiles (rapid absorption and short half-life) in rats. A phase 2a study of TS-142 using patients with insomnia has been completed, which is presented in a separate poster. Support Taisho Pharmaceutical. Co., Ltd.

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