Slow-wave Index Research Articles

Ocular emotion discrimination disorders in self-limited epilepsy patients with centrotemporal spikes complicated with electrical status epilepticus during sleep: A pediatric neuropsychological study.

We investigated the characteristics and factors influencing eye emotion recognition in self-limited epilepsy patients with centrotemporal spikes (SeLECTS) complicated with electrical status epilepticus during sleep (ESES). We selected SeLECTS (n=160) patients treated in the outpatient and inpatient departments of Anhui Children's Hospital from September 2020 to January 2022. According to the video electroencephalogram monitoring slow-wave index (SWI), SeLECTS patients with SWI<50% were assigned into the typical SeLECTS group (n=79), and patients with SWI ≥ 50% were assigned into the ESES group (n=81). Patients in the two groups were assessed by The Eye Basic Emotion Discrimination Task (EBEDT) and The Eye Complex Emotion Discrimination Task (ECEDT), respectively. Comparisons were made with age-, sex- and education level-matched healthy control participants. The correlation between the characteristics of emotional discrimination disorder in the eye area and the clinical influencing factors was analyzed in ESES group, and p ≤ .050 was the threshold for significance. Relative to the healthy control group, scores of sadness and fear in the typical SeLECTS group were markedly lower (p=.018, p=.023), while differences in scores of disgust, happiness, surprise, and anger were not significantly different between the groups (p=.072, p=.162, p=.395, p=.380, respectively). Compared with the healthy control group, the ESES group had significantly low scores in recognition of sadness, fear, disgust, and surprise (p=.006, p=.016, p=.043 and p=.038, respectively). However, differences in recognition of happiness and anger between the groups were not significant (p=.665 and p=.272). Univariate logistic analysis showed that the score of eye recognition for sadness in the ESES group was affected by age of onset, SWI, ESES duration and number of seizures. The score of eye recognition for fear was mainly affected by SWI, while the score of eye recognition for disgust was affected by SWI and number of seizures. The surprised eye emotion recognition score was mainly affected by the number of seizures. Variables with p<.1 were considered to be independent variables of multivariable ordered logistic regression. Multivariate logistic analysis showed that sadness emotion recognition was mainly affected by SWI and ESES duration, while disgust was mainly affected by SWI. The typical SeLECTS group showed impaired emotion (sadness and fear) recognition function in the eye area. The ESES group was associated with more intense emotional (sadness, fear, disgust, and surprise) recognition impairment in the eye region. The higher the SWI, the younger the onset age and the longer the duration of ESES, while the more the number of seizures, the more serious the impairment of emotional recognition function in the affected eye area.

A qualitative awake EEG score for the diagnosis of continuous spike and waves during sleep (CSWS) syndrome in self-limited focal epilepsy (SFE): A case-control study

PurposeTo determine whether awake EEG criteria can differentiate epileptic encephalopathy with continuous spike and waves during sleep (EE-CSWS) at the time of cognitive regression from typical, self-limited focal epilepsy (SFE). MethodsThis retrospective case-control study was based on the analysis of awake EEGs and included 15 patients with EE-CSWS and 15 age-matched and sex-matched patients with typical SFE. The EEGs were anonymised and scored by four independent readers. The following qualitative and quantitative EEG indices were analysed: slow-wave index (SLWI), spike-wave index (SWI), spike-wave frequency (SWF), long spike-wave clusters (CLSW) and EEG score (between grades 0 and 4). Sensitivity and specificity were assessed using receiver operating characteristic (ROC) curves and their reproducibility with a kappa test. ResultsBased on a highly sensitive cut-off, EE-CSWS patients were 8.4 times more likely than those with SFE to have an SLWI > 6%, 15 times more likely to have an SWI > 10 % and six times more likely to have a CLSW of ≥ 1 s. There was substantial agreement between readers (with kappa values of 0.64, 0.69 and 0.67). EE-CSWS patients were 13 times more likely to have an SWF of > 11 % and 149 times more likely to have an EEG score of ≥ 3 than typical SFE patients. Agreement about these ratings was almost perfect (kappa 0.91 and 0.86). ConclusionAn EEG score of ≥ 3 on a 20-min awake EEG differentiates typical SFE from EE-CSWS at the time of cognitive regression, with good reliability across readers with different levels of expertise.

Clinical effect of levetiracetam combined with topiramate in the treatment of refractory epilepsy syndrome

Objective To observe the clinical effect of levetiracetam combined with topiramate in the treatment of children with Lennox-Gastaut syndrome(LGS). Methods From January 2016 to August 2018, 60 cases of LGS syndrome admitted to the pediatrics department of Ganzhou People's Hospital were selected The patients were divided into left ethylancetan single drug treatment group, topiramate single drug treatment group, and left ethylancetin combined with topiramate treatment group according to the digital table, with 20 cases in each group.The children in the three groups were treated with the intervention of levetiracetam, topiramate and levetiracetam combined with topiramate according to the test requirements.After 8 weeks of treatment, the clinical efficacy was compared among the three groups in terms of efficacy, cranial magnetic resonance spectrum, eeg slow wave index and intelligence evaluation. Results The clinical effective rate(95%), NAA/Cho+ Cr(0.882±0.107), NAA/Cho(1.624±0.088) and NAA/Cr(1.634±0.042) of the combined treatment group were significantly higher than those before treatment, the differences were statistically significant(all P<0.05). The eeg slow wave index[(9.11±0.63)μV]and sleep period[(18.02±0.66)μV] were significantly lower than those before treatment, and the differences were statistically significant(all P<0.05). The comprehension scores[(15.62±2.55)points], FIQ scores[(106.85±2.64)points]and VIQ scores[(107.28±3.06)points]were significantly higher than those before treatment, the differences were statistically significant(all P<0.05). Conclusion Levetiracetam combined with topiramate in the treatment of refractory epilepsy syndrome has good curative effect, and is worthy of wide clinical application. Key words: Lennox-Gastaut syndrome; Levetiracetam; Topiramate; Treatment; Children

Object knowledge during entry-level categorization is activated and modified by implicit memory after 200 ms

The timing of activating memory about visual objects is important for theories of human cognition but largely unknown, especially for tasks like entry level categorization that activate semantic memory. We tested an implicit memory-categorization “equivalence” hypothesis of multiple memory systems theory that a cortical system that stores structural knowledge to support entry level categorization also stores long-term, perceptual implicit memory, resulting in priming of this knowledge. Event-related brain potentials (ERPs) were recorded to impoverished pictures of new and repeated objects that were similar in perceptual properties but differed in categorization success. The cortical dynamics of object knowledge were defined using categorization ratings and naming. As predicted, rating, naming, and repetition effects on a frontocentral N350 show that implicit memory modifies the object knowledge network supporting categorization. This ERP is a complex of components between 200 and 500 ms indexing temporally overlapping substates from more perceptual to more conceptual knowledge. A frontopolar N350 subcomponent defines the first substate of a process of object model selection from occipitotemporal cortex based on shape similarity, and indicates that implicit memory in this system is greater with better categorization success. Afterwards, parietal positivity and a slow wave index secondary, post-model selection processes, like evaluating the success of a decision or memory match, and working memory for overt report, respectively. Altogether, ERP findings support the equivalence hypothesis and a two-state interactive account of visual object knowledge, and delineate the timing of multiple memory systems.

A Taxonomic Analysis of Sleep Stages

To study the structure of human sleep at the level of sleep stages. We applied taxonomic statistics to detect significant configurations (types) of different physiologic variables and their relationship to sleep stages. DESIGN AND STATISTICS: Polygraphic sleep recordings from 32 subjects (normal sleepers as well as patients with insomnia, sleep apnea, or narcolepsy; n = 8 per group) were visually scored and submitted to a configural frequency analysis. The configural frequency analysis was computed with 3 continuous input variables: an electroencephalogram parameter, which represents the point of gravity of the EEG frequency distribution; the alpha slow-wave index, and the Rest Index, based on the presence or absence of phasic electromyographic activity. These variables were dichotomized for further analysis. The combination of 2 levels ( + or -) and 3 variables resulted in 2(3) patterns ( +++ to - - - ). The configural frequency analysis is a nonparametric X2-type multivariate statistic that identifies significant patterns or types. Each sleep stage contained 3 or 4 types. For non-rapid eye movement sleep stages 2, 3, and 4, types overlapped, whereas there was no overlap of types between stages 1 and 2. Types of rapid eye movement sleep did not overlap with those from stages 2, 3, and 4 but did overlap with wake and stage 1 types. The majority of observed types were significant in all 4 groups of subjects. Sleep stages appear to be less homogenous than rule-based sleep scoring would suggest. Types were either restricted to one stage or overlapped with neighboring stages.

Pharmacodynamic Effects of Acamprosate on Markers of Cerebral Function in Alcohol-Dependent Subjects Administered as Pretreatment and during Alcohol Abstinence

Animal studies suggested that acamprosate modulates neuronal hyperexcitability of acute alcohol withdrawal, acting through the glutamatergic neurotransmission. In the present study, we further investigated whether treatment with acamprosate could attenuate the post-alcohol withdrawal hyperexcitability or hyperarousal in humans using brain magnetoencephalography mapping of spontaneous fields. A double-blind, randomised, placebo-controlled study with a parallel group design comparing 2,000 mg/day of acamprosate versus placebo was conducted in alcohol-dependent subjects meeting DSM-IV criteria for alcohol dependence. Treatments were initiated 8 days before alcohol withdrawal and prolonged during the 15 following (abstinence) days. The study demonstrated that during alcohol withdrawal, acamprosate decreased the arousal level as reflected by alpha slow-wave index (ASI) measurement. This effect was mostly evidenced in left parietotemporal regions and, to a lesser extent, in the contiguous anterior, posterior and right-sided regions. In the placebo group, on the contrary, ASI measures increased between day 2 (acute withdrawal) and day 14 (prolonged withdrawal). The present results suggest a sustained effect of acamprosate on the hyperexcitability state due to alcohol withdrawal in alcohol-dependent patients and that acamprosate may have a protective effect when administered 8 days before alcohol withdrawal.

Temporal link between plasma thyrotropin levels and electroencephalographic activity in man

Plasma thyrotropin (TSH) levels have been previously shown to be associated with the internal sleep structure determined by conventional scoring of sleep stages. This temporal relationship was re-evaluated using spectral analysis of the sleep electroencephalogram (EEG). Eight healthy male subjects underwent two randomized night studies after having received either placebo or 5 mg ritanserin, a selective 5-HT 2 receptor antagonist known to increase slow-wave sleep. Delta relative power and TSH levels, determined at 10 min intervals, were found to be inversely related with an average cross-correlation coefficient highly significant ( P < 0.0001) in both experimental conditions. Alpha slow-wave index, an estimator of awakenings, and TSH pulses exhibited a significant temporal association in both conditions. These results demonstrate that TSH fluctuations are linked to the sleep EEG activity in man.

A Computerized Method for Detecting Episodes of Wakefulness During Sleep Based on the Alpha Slow-Wave Index (ASI)

A method for the automatic detection of episodes of wakefulness during sleep is presented. The algorithm is based on the evaluation of the alpha slow-wave index (ASI), a measure that has been developed to detect fluctuations of vigilance in daytime pharmaco-electroencephalogram studies. Its application to sleep data was validated with polysomnographic recordings from 16 elderly insomniacs and 16 young healthy subjects. The rate of agreement between the computerized procedure and the visual scoring of wakefulness was 94.0% for the insomniacs and 96.9% for the healthy subjects. The decision criterion used by the computer allowed the definition of a subject-adapted threshold for the detection of wake episodes. The method opens new perspectives for the automatic analysis of continuous 24-hour sleep-wake recordings.

Pharmaco-EEG Profile of Maroxepine:

This publication forms the third part of a critical evaluation of pharmaco-EEG applications as an instrument for assessing the profile of action of psychoactive drugs based on the trial results of three new psychoactive test substances: savoxepine, levoprotiline and maroxepine. After the presentation, in Parts I (savoxepine) and II (levoprotiline), of trial substances for which compatible results were obtained in the pharmaco-EEG model and in the clinical studies, a case with discrepant and less predictive results has been presented, and on this basis the limitations of the pharmaco-EEG model in the evaluation of therapeutic efficacy are discussed. The substance examined in this report, the tetracyclic dibenzoxepine derivative, maroxepine, produced prominent central effects in pharmacological studies which pointed to a bipolar profile of action, i.e., the EEG showed similarities both to antidepressants and antipsychotics. The pharmaco-EEG effects of maroxepine were investigated in a randomised, double-blind study in 15 young healthy male subjects and compared with those of placebo and the reference substances, chlorpromazine and imipramine. The experimental design was a cross-over uncompleted block design with five consecutive trial days one week apart. The pharmaco-EEG was recorded from the occipito-temporal and frontocentral regions before, 3 and 6 h after application of 2.5 mg and 5.0 mg maroxepine, 75 mg chlorpromazine, 75 mg imipramine and placebo. The selected target variables for descriptive statistical evaluation were the Spectral Difference Index (SDI), the absolute and relative power values in seven predetermined frequency bands within the range 1.5 to 30.0 Hz, the dominant frequency (6.0 to 18.0 Hz) and the alpha slow-wave index (ASI). The results show that maroxepine has a potent central nervous action and a strong sedative potential. The EEG effects consisted of a shift to the left of the relative power spectrum of the occipital lead, accompanied by an increase in the absolute beta power in the frontocentral region. Discriminative inspection of the profiles of EEG changes, induced by maroxepine and the reference drugs, revealed closer similarity of maroxepine with chlorpromazine than with imipramine. Maroxepine showed vigilance-decreasing features like imipramine. This is one condition to be able to interfere with depressive illness. The underlying hypothesis is that depressive illness is based on affective and vigilance disturbance. Maroxepine furthermore showed the typical neuroleptic-like shift from resting alpha to resting subalpha (theta F band) which we assume related to the anti-productive properties of neuroleptics in schizophrenia.(ABSTRACT TRUNCATED AT 400 WORDS)

Prestimulus spectral EEG patterns and the evoked auditory vertex response

A vigilance-related index (slow wave index, SWI) representing the relative delta + theta amplitude of the 1 sec prestimulus EEG spectrum has been related to latencies and amplitudes of the auditory cortical evoked response (EP) in 12 volunteers. Stimuli were 70 dB SL tone bursts derivered at 10 sec ISI. Four selective averages were obtained for each subject according to the subdivision of the SWI into quartiles. The subjects were divided into 2 groups having individual mean SWI values above or below the group's median SWI. Repeated measures MANOVA showed that N1 latency increased within subjects from the first to the fourth SWI quartile and that it was longer in subjects with high mean SWIs. N1-P2 amplitude decreased within subjects from the first to the fourth SWI quartile, but only in the group with high mean SWI.

Intravenous administration of diazepam in patients with chronic liver disease.

The EEG response and drug kinetics after intravenous infusion of diazepam at 1-0 mg/min until nystagmus, dysarthria, and moderate sedation developed, has been investigated in five normal subjects and 17 patients with chronic liver disease. Diazepam induced adequate premedication with a similar clinical response in all subjects with no adverse reactions. Maximal response was during or within five minutes of infusion. The dose of diazepam required in liver chronic disease was 17-9 +/- 1-4 mg (M +/- SEM) compared with 27 +/- 5-4 mg in controls (p less than 0-01). Dose correlated significantly with serum albumin (p less than 0-05). Baseline mean dominant frequency (MDF) and slow wave index (SWI) significantly correlated with albumin (p less than 0-01). After diazepam, the MDF decreased and SWI increased. The change was greatest at the time of maximal clinical response. It was greater in liverdisease and was greatest in patients with previous hepaticencephalopathy. In spite of reduced dose requirements in liver disease, there was no significant difference in plasma concentration at the end of drug infusion...