Seizures In Period Research Articles

Diagnostic value of high frequency oscillation in localization of type Ⅱ focal cortical dysplasia epilepsy

Retrospective analysis was conducted on 9 patients with type Ⅱ focal cortical dysplasia (FCD) who underwent stereo-electroencephalography (SEEG) implantation in the Department of Neurosurgery of the First Affiliated Hospital of Fujian Medical University from November 2020 to February 2023. The onset area, onset time, and frequency of high-frequency oscillations (HFO) were analyzed and the correlation of HFOs with interictal, preictal, and ictal periods. SEEG recordings of 80-500 Hz HFOs were observed in both interictal and ictal periods in 9 patients, with 6 patients exhibiting fast ripples (FR) in the range of 250-500 Hz. Surgical resection of the seizure onset area and FR-generating electrodes was performed, and postoperative follow-up for over 2 years indicated Engel I in 5 cases. 6 patients showed continuous discharge during the preictal period, and the distribution index of continuous discharge was positively correlated with seizure frequency. HFOs in the range of 80-500 Hz were present in all four seizure onset patterns during the ictal period. The onset area and FR-emitting electrode were surgically removed in 6 patients with continuous discharge and overlapping HFOs during the preictal period, with 5 cases of Engel I. Type Ⅱ FCD discharges exhibited complexity, high discharge indices, and a close association with HFOs. Compared with the spike wave, the electrode range of HF is more limited, and the incidence of HF before attack is significantly increased, which is closely correlated with the onset area. The simultaneous occurrence of HFO and the spike waves has higher diagnostic value than the individual occurrence, effectively enhancing surgical efficacy.

Measurable transitions during seizures in intracranial EEG: A stereoelectroencephalography and SPECT study

ObjectiveIctal Single Photon Emission Computed Tomography (SPECT) and stereo-electroencephalography (SEEG) are diagnostic techniques used for the management of patients with drug-resistant focal epilepsies. While hyperperfusion patterns in ictal SPECT studies reveal seizure onset and propagation pathways, the role of ictal hypoperfusion remains poorly understood. The goal of this study was to systematically characterize the spatio-temporal information flow dynamics between differently perfused brain regions using stereo-EEG recordings. MethodsWe identified seizure-free patients after resective epilepsy surgery who had prior ictal SPECT and SEEG investigations. We estimated directional connectivity between the epileptogenic-zone (EZ), non-resected areas of hyperperfusion, hypoperfusion, and baseline perfusion during the interictal, preictal, ictal, and postictal periods. ResultsCompared to the background, we noted significant information flow (1) during the preictal period from the EZ to the baseline and hyperperfused regions, (2) during the ictal onset from the EZ to all three regions, and (3) during the period of seizure evolution from the area of hypoperfusion to all three regions. ConclusionsHypoperfused brain regions were found to indirectly interact with the EZ during the ictal period. SignificanceOur unique study, combining intracranial electrophysiology and perfusion imaging, presents compelling evidence of dynamic changes in directional connectivity between brain regions during the transition from interictal to ictal states.

Luteolin ameliorates pentetrazole-induced seizures through the inhibition of the TLR4/NF-κB signaling pathway

Epilepsy represents a prevalent neurological disorder in the population, and the existing antiepileptic drugs (AEDs) often fail to adequately control seizures. Inflammation is recognized as a pivotal factor in the pathophysiology of epilepsy. Luteolin, a natural flavonoid extract, possesses anti-inflammatory properties and exhibits promising neuroprotective activity. Nevertheless, the precise molecular mechanisms underlying the antiepileptic effects of luteolin remain elusive. In this study, we established a rat model of epilepsy using pentylenetetrazole (PTZ) to induce seizures. A series of behavioral experiments were conducted to assess behavioral abilities and cognitive function. Histological techniques, including HE staining, Nissl staining, and TUNEL staining, were employed to assess hippocampal neuronal damage. Additionally, Western blotting, RT-qPCR, and ELISA were utilized to analyze the expression levels of proteins involved in the TLR4/IκBα/NF-κB signaling pathway, transcription levels of apoptotic factors, and levels of inflammatory cytokines, respectively. Luteolin exhibited a dose-dependent reduction in seizure severity, prolonged the latency period of seizures, and shortened seizure duration. Furthermore, luteolin prevented hippocampal neuronal damage in PTZ-induced epileptic rats and partially restored behavioral function and learning and memory abilities. Lastly, PTZ kindling activated the TLR4/IκBα/NF-κB pathway, leading to elevated levels of the cytokines TNF-α, IL-6 and IL-1β, which were attenuated by luteolin. Luteolin exerted anticonvulsant and neuroprotective activities in the PTZ-induced epileptic model. Its mechanism was associated with the inhibition of the TLR4/IκBα/NF-κB pathway, alleviating the immune-inflammatory response in the post-epileptic hippocampus.

Temporal evolution of electrographic seizures in newborn infants with hypoxic-ischaemic encephalopathy requiring therapeutic hypothermia: a secondary analysis of the ANSeR studies

Despite extensive research on neonatal hypoxic-ischaemic encephalopathy, detailed information about electrographic seizures during active cooling and rewarming of therapeutic hypothermia is sparse. We aimed to describe temporal evolution of seizures and determine whether there is a correlation of seizure evolution with 2-year outcome. This secondary analysis included newborn infants recruited from eight European tertiary neonatal intensive care units for two multicentre studies (a randomised controlled trial [NCT02431780] and an observational study [NCT02160171]). Infants were born at 36+0 weeks of gestation with moderate or severe hypoxic-ischaemic encephalopathy and underwent therapeutic hypothermia with prolonged conventional video-electroencephalography (EEG) monitoring for 10 h or longer from the start of rewarming. Seizure burden characteristics were calculated based on electrographic seizures annotations: hourly seizure burden (minutes of seizures within an hour) and total seizure burden (minutes of seizures within the entire recording). We categorised infants into those with electrographic seizures during active cooling only, those with electrographic seizures during cooling and rewarming, and those without seizures. Neurodevelopmental outcomes were determined using the Bayley's Scales of Infant and Toddler Development, Third Edition (BSID-III), the Griffiths Mental Development Scales (GMDS), or neurological assessment. An abnormal outcome was defined as death or neurodisability at 2 years. Neurodisability was defined as a composite score of 85 or less on any subscales for BSID-III, a total score of 87 or less for GMDS, or a diagnosis of cerebral palsy (dyskinetic cerebral palsy, spastic quadriplegia, or mixed motor impairment) or epilepsy. Of 263 infants recruited between Jan 1, 2011, and Feb 7, 2017, we included 129 infants: 65 had electrographic seizures (43 during active cooling only and 22 during and after active cooling) and 64 had no seizures. Compared with infants with seizures during active cooling only, those with seizures during and after active cooling had a longer seizure period (median 12 h [IQR 3-28] vs 68 h [35-86], p<0·0001), more seizures (median 12 [IQR 5-36] vs 94 [24-134], p<0·0001), and higher total seizure burden (median 69 min [IQR 22-104] vs 167 min [54-275], p=0·0033). Hourly seizure burden peaked at about 20-24 h in both groups, and infants with seizures during and after active cooling had a secondary peak at 85 h of age. When combined, worse EEG background (major abnormalities and inactive background) at 12 h and 24 h were associated with the seizure group: compared with infants with a better EEG background (normal, mild, or moderate abnormalities), infants with a worse EEG background were more likely to have seizures after cooling at 12 h (13 [54%] of 24 vs four [14%] of 28; odds ratio 7·09 [95% CI 1·88-26·77], p=0·0039) and 24 h (14 [56%] of 25 vs seven [18%] of 38; 5·64 [1·81-17·60], p=0·0029). There was a significant relationship between EEG grade at 12 h (four categories) and seizure group (p=0·020). High total seizure burden was associated with increased odds of an abnormal outcome at 2 years of age (odds ratio 1·007 [95% CI 1·000-1·014], p=0·046), with a medium negative correlation between total seizure burden and BSID-III cognitive score (rS=-0·477, p=0·014, n=26). Overall, half of infants with hypoxic-ischaemic encephalopathy had electrographic seizures and a third of those infants had seizures beyond active cooling, with worse outcomes. These results raise the importance of prolonged EEG monitoring of newborn infants with hypoxic-ischaemic encephalopathy not only during active cooling but throughout the rewarming phase and even longer when seizures are detected. Wellcome Trust, Science Foundation Ireland, and the Irish Health Research Board.

Therapeutic Strategies in Children with Epilepsy: A Quality-of-Life-Related Perspective.

Back ground: Children with epilepsy are affected by several factors, including clinical and social variables. Among these variables, cognitive decline and behavioral disturbances, perceptions of stigma, and fatigue can lead to reductions in quality of life (QOL). Epileptic activities, including seizure severity, frequent seizures, and status epilepticus (SE), have been identified as important predictors of QOL. In addition, the frequency of interictal epileptiform discharges (IEDs) on electroencephalogram (EEG) may also be an important predictor of QOL, because IEDs can lead to cognitive decline and behavioral disturbances. Moreover, frequent seizures and/or IEDs may play a role in emotional mediators, such as stigma and fatigue, in childhood epilepsy. Seizure severity and/or IEDs are, therefore, important QOL-related factors in childhood epilepsy. Seizure severity as a QOL-related factor: Frontal lobe dysfunctions, such as cognitive decline and behavioral disturbances, can result in reduced QOL for both the child and their family. Frontal and prefrontal lobe growth disturbances can be present during active-phase epilepsy in some children with neuropsychological impairments. Recovery from prefrontal lobe growth disturbances may depend on the active seizure period. Children with a shorter active seizure period can recover from disturbances in prefrontal lobe growth more rapidly. In contrast, recovery may be delayed in children with a longer active seizure period. Moreover, frequent seizures can lead to seizure-associated headaches, perceptions of self-stigma and parental stigma, and fatigue. Accordingly, severe seizures can lead to neuropsychological impairments in association with prefrontal lobe growth disturbances in children with epilepsy. EEG abnormalities as QOL-related factors: IEDs on EEG, representing persistent pathological neuronal discharges, may be associated with several pathological aspects. Frontal IEDs can be a risk factor for recurrent seizures, cognitive decline, and behavioral disturbances, and they may also play a role as emotional mediators similar to stigma. In addition, behavioral disturbances may result in the presence of secondary bilateral synchrony (SBS) on EEG. Behavioral disturbances can be improved in association with a reduction in IEDs in children with frontal IEDs and SBS. Therefore, EEG abnormalities, such as frontal IEDs and SBS, can also lead to neuropsychological impairments in children with epilepsy. Therapeutic strategies in children with epilepsy: Seizure severity and IEDs on EEG may be associated with neuropsychological impairments, leading to QOL reduction. Therapeutic management may be desirable to reduce seizures and EEG abnormalities, such as frontal IEDs and SBS, as early as possible to improve QOL in children with epilepsy. During antiseizure medication (ASM) selection and adjustment, physicians should strategize the therapeutic approach to controlling seizures and suppressing EEG abnormalities in children with epilepsy. Among various ASMs, novel ASMs, such as levetiracetam and perampanel, may suppress both clinical seizures and IEDs on EEG; thus, these novel ASMs may represent an important addition to the treatments available for epileptic children presenting with frontal IEDs and SBS.

Disruption of TLE epileptiform activity retarded the seizure and reduced pathological HFOs

In temporal lobe epilepsy (TLE), the epileptogenic zones, such as the temporal lobe structure, could generate pathological high-frequency oscillations (pHFOs, 250–500 Hz) before the ictal period. These pHFOs have also been observed during the process of seizures in both TLE patients and animals, exhibiting a critical role as promising biomarkers for TLE seizures. TLE seizures could be modulated via regulating the neural excitability in epileptogenic zones, for that TLE is primarily associated with the excitation-inhibition imbalance. However, whether these kinds of modulations could also impact the pHFOs characteristics during TLE seizures is still unclear. For this purpose, we pharmaco-genetically inhibited the principal cells (PCs) in the mouse CA3 region and tracked the difference in the behavioral and electrophysiological features during LiCl-pilocarpine-induced TLE seizure between the hM4Di+CNO (experimental) mice and mCherry+CNO (control) mice. Delayed latency, decreased averaged duration, and reduced counts of the generalized seizure were observed in the experimental mice. Besides, the electrophysiological characteristics, such as the firing rate of PCs and the count of pHFO, exhibited significant decline in the CA3 and CA1 regions. During TLE seizure, there existed strong phase-coupling between pHFO and PCs spike timing in the control mice, while it was abolished in the experimental mice. In addition, we also found that the counts of pHFO were significantly associated with the behavioral features, indicating the close relationships within them. Collectively, our findings suggested that alterations in pHFO and the retardation of seizures may be attributed to disruptions in neuronal excitability, and the variations of electrophysiological features were related to seizure severity during TLE seizures. These results provide valuable insights into the role of pHFOs in TLE and shed light on the underlying mechanisms involved.

Decrease in phase slip rates and phase cone structures during seizure evolution and epileptogenic activities derived from microgrid ECoG data

Sudden phase changes are related to cortical phase transitions, which likely change in frequency and spatial distribution as epileptogenic activity evolves. A 100 s long section of micro-ECoG data obtained before and during a seizure was selected and analyzed. In addition, nine other short-duration epileptic events were also examined. The data was collected at 420 Hz, imported into MATLAB, downsampled to 200 Hz, and filtered in the 1–50 Hz band. The Hilbert transform was applied to compute the analytic phase, which was then unwrapped, and detrended to look for sudden phase changes. The phase slip rate (counts/s) and its acceleration (counts/s2) were computed with a stepping window of 1-s duration and with a step size of 5 ms. The analysis was performed for theta (3–7 Hz), alpha (7–12 Hz), and beta (12–30 Hz) bands. The phase slip rate on all electrodes in the theta band decreased while it increased for the alpha and beta bands during the seizure period. Similar patterns were observed for isolated epileptogenic events. Spatiotemporal contour plots of the phase slip rates were also constructed using a montage layout of 8 × 8 electrode positions. These plots exhibited dynamic and oscillatory formation of phase cone-like structures which were higher in the theta band and lower in the alpha and beta bands during the seizure period and epileptogenic events. These results indicate that the formation of phase cones might be an excellent biomarker to study the evolution of a seizure and also the cortical dynamics of isolated epileptogenic events.

Biological Activity study of the &lt;i&gt;Melampyrum sylvaticum&lt;/i&gt; Extract

Introduction. Among wild plants that have an effect on the nervous system, species of the genus Melampyrum L. are distinguished, in particular, Melampyrum sylvaticum L. Extracts from the aerial part of the plant have long been used in folk medicine as sedatives and anticonvulsants. Currently, a number of studies are being carried out to confirm the possibility of using wildflower and drugs based on it in scientific medicine, as well as to obtain a drug with low toxicity, complex sedative and anticonvulsant activity, which will expand the arsenal of drugs used to treat diseases of the nervous system.Aim. To investigate the in vivo acute toxicity, anticonvulsant and sedative activity of a dry alcohol extract from the aerial part of Melampyrum sylvaticum.Materials and methods. The extract was obtained by extracting substances from the aerial part of Melampyrum sylvaticum with 50 % ethanol, by the method of repercolation with an equal loading of raw materials, followed by evaporation to a dry residue. The study of pharmacological properties was carried out on nonlinear white mice of both sexes weighing 17–25 g. Acute toxicity of the extract was determined by oral administration in doses up to 5000 mg/kg. Anticonvulsant activity was evaluated in the corazole convulsion test, sedative activity was evaluated in the open field test.Results and discussion. When determining the acute toxicity of a dry alcoholic extract from the aerial part of Melampyrum sylvaticum, there was no lethality in the experimental group of animals. LD50 could not be determined. In the corazol convulsion test, it was shown that oral administration of the extract at a dose of 100 mg/kg does not affect the latent period of convulsions, but significantly increases the life expectancy of animals. At a dose of 200 mg/kg, the latent period of seizures and life expectancy significantly increased, and the survival rate of animals was 20 %. When studying sedative activity of the extract from Melampyrum sylvaticum in the open field test, a decrease in vertical activity, a decrease in the number of vertical stands, a decrease in horizontal activity along the periphery and the number of animals entering the center of the area were noted, which indicates a suppression of orienting-exploratory behavior. In the experiment, there was a decrease in the intensity of grooming as an indicator of anxiety for this group of animals. A course of administration of the extract for thirty days led to a decrease in the vertical activity of mice and inhibition of orienting-exploratory behavior.Conclusion. It was found that a dry alcoholic extract from the aerial part of Melampyrum sylvaticum exhibits biological activity in animal experiments, compensating for the effect of corazol, and has a pronounced anticonvulsant and sedative effect. The LD50 of the extract when administered orally was more than 5000 mg/kg.

PREDICTION OF EPILEPSY BASED ON EEMD AND LSSVM DOUBLE CLASSIFICATION

Epilepsy seizures are caused by abnormal, excessive, or synchronized neuronal activity in the brain, which is difficult to treat and is extremely stubborn. Therefore, studying the activity of epilepsy can greatly contribute to its diagnosis and treatment. The original signal is decomposed into IMFs and residual by ensemble empirical mode decomposition (EEMD), and then the first three intrinsic mode functions (IMF) are selected to replace the original signal, and the nonlinear and non-stationary problems of the original signal are solved. The Least Squares Support Vector Machine (LSSVM) was used as the classifier, its parameters (gam and sig2) are optimized by Particle Swarm Optimization (PSO). The experiment used the EEG database published by the University of Bonn (UoB) to realize the classification of normal, interictal and ictal periods. When PSO was employed, the recognition accuracy of the test set was 93.33%, with a classification time of 0.035 s and the Information Transfer Rate (ITR) of 3.77 bpm in training 70 classes with 100 samples each. In contrast, without PSO, the recognition accuracy of the test set was 92%, with a classification time of 0.039 s and the ITR of 2.88 bpm without PSO in training 70 classes with 100 samples each. The experimental results show that EEMD and LSSVM can effectively implement the three-classification problem and provide an effective means for the onset prediction of epilepsy patients.

Reduction in retinal microvascular perfusion during migraine attacks.

To determine if there are changes in structure and function of the retinal vasculature during and between migraine attacks using optical coherence tomography angiography (OCTA). Migraine attacks commonly include visual symptoms, but the potential role of the retina in these symptoms is not well understood. OCTA is a rapid, non-invasive imaging technique that is used to visualize the retinal microvasculature with high spatial resolution in a clinical setting. In this study we used OCTA to quantify different features of the retinal vasculature in patients with migraine during and between attacks, as well as in healthy controls (HCs). We performed a prospective cohort study of 37 patients with migraine with aura (MA) (median [interquartile range, IQR] age of 37 [14] years, 86% female) and 30with migraine without aura (MO) (median [IQR] age of 37 [17] years, 77% female) and 20 HCs (median [IQR] age of 35 [7] years, 50% female). Macular OCTA scans were obtained for all participants for the interictal analysis. In 12 MA and eight MO, scans were captured both during and outside of migraine attacks and five HCs had initial and repeat scans. In addition to analyzing the morphology of the foveal avascular zone, we calculated the vessel flux index (VFI), which is an indicator of retinal perfusion and conventional metrics (such as vessel area density) in the foveal and parafoveal regions. There was a significant difference in the parafoveal VFI in the ictal state between the groups (p = 0.009). During migraine attacks there was a significant reduction in the parafoveal region VFI in MA (-7%, 95% confidence interval [CI] -10% to -4%; p = 0.006) and MO (-7%, 95% CI -10% to -3%; p = 0.016) from their interictal baseline as compared to the change between repeat scans in HCs (2%, 95% CI -3% to 7%). Interictally, there was a mean (standard deviation [SD]) 13% (10%) (p = 0.003) lower blood perfusion in the MA group as compared to the MO group in the foveal region (mean [SD] 0.093 [0.023] vs. 0.107 [0.021], p = 0.003). Interictal analysis also revealed higher circularity in the superficial foveal avascular zone in the MA group compared with the MO group (mean [SD] 0.686 [0.088] vs. 0.629 [0.120], p = 0.004). In addition, interictal analysis of the patients with MA or MO and unilateral headache showed increased retinal vascular parameters consistent with greater perfusion in the eye ipsilateral to the side of the pain as compared with the contralateral eye. These results indicate that perfusion is reduced in MA and MO in the parafoveal retina during the ictal period. Interictally, the foveal retina in MA has reduced perfusion when compared to the foveal retina in MO. Patients with unilateral headache showed interictal asymmetry of retinal perfusion between eyes. These results indicate that changes in retinal perfusion could be a part of migraine pathophysiology, and that distinct retinal vascular signatures identified with OCTA could represent biomarkers for migraine.

Time and frequency domain pre-processing for epileptic seizure classification of epileptic EEG signals

Although epilepsy is one of the most prevalent and ancient neurological disorder, but, still difficult to identify the specific type of seizure, due to artefacts, noise, and other disturbances, because of acquisition of Scalp EEG. It necessitating the use of skilled medical professionals as incorrect diagnosis lead to wrong Anti Seizure Drug (ASDs) and face it’s side effects. On the other hand machine learning plays a crucial role in seizure detection by analyzing and identifying patterns in brain activity data that are indicative of seizures. It can be used to develop predictive models that can detect the onset of seizures in real-time, allowing for early intervention and improved patient outcomes. Most of the research work focuses on seizure detection using various machine learning techniques pre-processed by different mathematical models. But, very less attention is paid towards seizure type detection. In this study, multiple Machine and Deep Learning algorithms were used in conjunction with time-domain and frequency-domain pre-processing to classify epileptic seizures into multiple types. The ictal period of various seizure types were extracted from Temple University Hospital EEG (TUHEEG) and the pre-processed data was tried out with multiple classifiers, including support vector classifiers (SVC), K- Nearest Neighbor (KNN), and Long short term memory (LSTM), among others. By using SVM, KNN, and LSTM, multiclass classification of seven types of epileptic seizures with 19 channels were considered for each EEG data and a 75–25 train–test ratio was accomplished with 90.41%, 94.46%, and 86.2% accuracy respectively. Epileptic seizure’s ictal phase EEG signals are categorized using a variety of machine learning(ML) and deep learning(DL) methods after being pre-processed using time domain and frequency domain approaches. The KNN yields the best results of all.

Study of the anticonvulsant activity of the original valproic acid amino ester in various models of convulsive syndrome

Introduction. Despite a significant number of antidotes (atropine, pyridoxine) and anti-seizure drugs in clinical practice (benzodiazepines, barbiturates, valproates, anesthetics), the development of new antidotes for the relief of refractory seizures and recurrence of convulsive syndrome is actual problem. &#x0D; The aim of the work was to study the specific pharmacological activity of a new original derivative of valproic acid in an experiment on models of convulsive syndrome with different mechanisms of action.&#x0D; Material and methods. A comparative study of the effectiveness of the original substance ((1-methylpiperidin-4-yl)-2-propylpentanoate hydrochloride, VAA) was carried out on electroshock, GABA-lytic, catecholamine-dependent seizure models in rats and mice.&#x0D; Results. A significant decrease in seizure activity was revealed in the group with prophylactic administration &#x0D; of VAA in the dose range of 11, 27 and 65 mg/kg in comparison with the control group received only phenylcarbamate. In an intergroup comparison, a low dose (11 mg/kg) more than others had an effect on the latent period of the onset of phenylcarbamate seizures, an average dose (27 mg/kg) reduced the duration of the seizure period, a high dose (65 mg/kg) affected the severity of convulsions, while the integral indicator (convulsive activity) did not differ between the medium and high dose subgroups. There was no significant decrease in seizure activity in models with the use of corazol, camphor, and the model of maximum electric shock.&#x0D; Limitations. Testing of new pharmaceutical substances (study of efficacy and safety) should be carried out on laboratory animals before confirmation of efficacy in humans. The quantity of animals was limited by the need to comply with bioethical principles and sufficient number for statistically significant results and amounted &#x0D; 6 individuals in each group.&#x0D; Conclusion. The release of valproic acid during the metabolism of VAA is slow and its concentration is insufficient to realize the universal anticonvulsant activity of VAA. It is necessary to further study the effect on cognitive functions and neuroprotective properties. Since antidote efficacy superior to atropine has been previously demonstrated, VAA is recommended for development as an antidote for organophosphorus poisoning.

Epileptic EEG Signal Detection Using Variational Modal Decomposition and Improved Grey Wolf Algorithm.

Epilepsy does great harm to the human body, and even threatens human life when it is serious. Therefore, research focused on the diagnosis and treatment of epilepsy holds paramount clinical significance. In this paper, we utilized variational modal decomposition (VMD) and an enhanced grey wolf algorithm to detect epileptic electroencephalogram (EEG) signals. Data were extracted from each patient's preseizure period and seizure period of 200 s each, with every 2 s as a segment, meaning 100 data points could be obtained for each patient's health period as well as 100 data points for each patient's epilepsy period. Variational modal decomposition (VMD) was used to obtain the corresponding intrinsic modal function (VMF) of the data. Then, the differential entropy (DE) and high frequency detection (HFD) of each VMF were extracted as features. The improved grey wolf algorithm is adopted for a selected channel to improve the maximum value of the channel. Finally, the EEG signal samples were classified using a support vector machine (SVM) classifier to achieve the accurate detection of epilepsy EEG signals. Experimental results show that the accuracy, sensitivity and specificity of the proposed method can reach 98.3%, 98.9% and 98.5%, respectively. The proposed algorithm in this paper can be used as an index to detect epileptic seizures and has certain guiding significance for the early diagnosis and effective treatment of epileptic patients.

CA3 principal cell activation triggers hypersynchronous-onset seizures in a mouse model of mesial temporal lobe epilepsy.

Mesial temporal lobe epilepsy (MTLE) is the most common form of focal epilepsy and it is characterized by seizures that are often refractory to medications. Seizures in MTLE have two main patterns of onset that have been termed hypersynchronous (HYP) and low-voltage fast (LVF) and are believed to mainly depend on the activity of excitatory principal cells and inhibitory interneurons, respectively. In this study, we investigated whether unilateral open-loop optogenetic activation of CaMKII-positive principal cells in the hippocampus CA3 region favors the generation of spontaneous HYP seizures in kainic acid-treated (KA) CaMKII-ChR2 mice. Optogenetic activation of CA3 principal cells (1 Hz, 180 s ON, 220 s OFF) was implemented for 15 days after KA-induced status epilepticus. We found that both LVF and HYP seizures occurred in nonstimulated CaMKII-ChR2 (n = 6) and stimulated CaMKII-Cre (n = 5) mice. In contrast, optogenetic activation of principal cells in CaMKII-ChR2 mice (n = 5) triggered only HYP seizures that were characterized by high fast ripple (250-500 Hz) rates during the pre-ictal and ictal periods. These results provide firm evidence that in MTLE spontaneous seizures with different onset patterns depend on distinct neuronal network mechanisms of generation. They also demonstrate that HYP seizures occurring in vivo along with their associated fast ripples depend on the activity of principal cells in the CA3 region.NEW & NOTEWORTHY Previous evidence suggested that different seizure onset patterns rely on the activity of distinct neuronal populations. In this study, we show for the first time that in vivo optogenetic stimulation of CaMKII principal cells in kainic acid-treated mice triggers hypersynchronous-onset seizures that are associated with fast ripples. Our findings indicate that in patients with predominant HYP-onset seizures, anticonvulsant treatments should be aimed at limiting the firing of principal neurons in the seizure onset zone.

Alterations of β-γ coupling of scalp electroencephalography during epilepsy

Uncovering the alterations of neural interactions within the brain during epilepsy is important for the clinical diagnosis and treatment. Previous studies have shown that the phase-amplitude coupling (PAC) can be used as a potential biomarker for locating epileptic zones and characterizing the transition of epileptic phases. However, in contrast to the θ-γ coupling widely investigated in epilepsy, few studies have paid attention to the β-γ coupling, as well as its potential applications. In the current study, we use the modulation index (MI) to calculate the scalp electroencephalography (EEG)-based β-γ coupling and investigate the corresponding changes during different epileptic phases. The results show that the β-γ coupling of each brain region changes with the evolution of epilepsy, and in several brain regions, the β-γ coupling decreases during the ictal period but increases in the post-ictal period, where the differences are statistically significant. Moreover, the alterations of β-γ coupling between different brain regions can also be observed, and the strength of β-γ coupling increases in the post-ictal period, where the differences are also significant. Taken together, these findings not only contribute to understanding neural interactions within the brain during the evolution of epilepsy, but also provide a new insight into the clinical treatment.

Mitochondrial metabolism related markers GDF-15, FGF-21, and HIF-1α are elevated in pediatric migraine attacks.

The purpose of this study was to investigate the serum levels of mitochondrial metabolism/reactive oxygen species (ROS)-related peptides (hypoxia inducible factor-1α [HIF-1α], fibroblast growth factor-21 [FGF-21], growth differentiation factor-15 [GDF-15]) and key migraine-related neuropeptides (calcitonin gene-related peptide [CGRP], pituitary adenylate cyclase-activating peptide-38 [PACAP-38], substance P [SP], and vasoactive intestinal peptide [VIP]) during migraine attacks and to evaluate their diagnostic value in pediatric migraine. There is increasing evidence for the important role of impairment in oxidative mitochondrial metabolism in the pathophysiology of migraine. Potential biomarkers that may reflect the relationship between migraine and mitochondrial dysfunction are unclear. A total of 68 female pediatric migraine patients without aura and 20 female healthy controls aged 8-18 years, admitted to the hospital, were enrolled in this cross-sectional study. Serum concentrations of these molecules were determined by enzyme-linked immunosorbent assays, and clinical features and their possible diagnostic value were analyzed. Serum levels of HIF-1α (252.4 ± 51.9 [mean ± standard deviation]) pg/mL), GDF-15 (233.7 ± 24.7 pg/mL), FGF-21 (96.1 ± 13.1 pg/mL), CGRP (44.5 ± 11.3), and PACAP-38 (504.7 ± 128.9) were significantly higher in migraine patients compared to healthy controls (199.8 ± 26.8, 192.8 ± 20.7, 79.3 ± 4.1, 34.1 ± 3.5 and 361.2 ± 86.3 pg/mL, respectively). The serum levels of these peptides were also higher in patients with chronic migraine than in patients with episodic migraine, and higher in the ictal period than in the interictal period. A positive correlation was found between attack frequency and both HIF-1α and FGF-21 levels in migraine patients. Serum levels of VIP and SP were not different between the migraine patients and healthy controls. Migraine attacks are accompanied by elevated HIF-1α, FGF-21, GDF-15, CGRP, and PACAP-38 in medication-naive pediatric patients with migraine. Elevated circulating mitochondrial metabolism/ROS-related peptides suggest a mitochondrial stress in pediatric migraine attacks and may have potential diagnostic value in monitoring disease progression and treatment response in children. Novel approaches intervening with mitochondrial metabolism need to be investigated.

HFA analysis using scalp electroencephalograms in two cases of Rasmussen’s syndrome

ObjectiveIn recent years, wide-band EEGs have been used to assess brain activity, and their effectiveness in the pathological analysis of epilepsy has been demonstrated. This report describes two cases of Rasmussen’s syndrome (RS) in which high-frequency scalp EEGs were retrospectively analyzed to assess the pathological condition of epilepsy in RS. MethodsThe two RS cases were divided into three periods: incipient, stable, and frequent seizure periods. Using the EEG record of each period, interictal epileptiform discharges (IEDs) were visually extracted. Subsequently, a time–frequency analysis was performed to calculate the rate of high-frequency activities (HFAs) (IED–HFA rate). Finally, differences between the three periods were examined. ResultsIED–HFA rates significantly increased in the frequent seizure period compared with the stable period in both cases(P < 0.05). Conclusionthere was a significant increase in HFAs superimposed over IEDs during the frequent seizure period compared to the stable period. HFAs are thought to be associated with epileptogenicity. Similarly, HFAs could be a useful biomarker for the pathological condition of epilepsy in RS.

Long-term effect associated with seizures and dynamic effect associated with treatment on cognitive dysfunction of adult patients with focal epilepsy as evaluated by the Trail Making Test.

This study was performed to clarify the utility of the Trail Making Test (TMT) in evaluating the effects of the course of epilepsy on cognitive function by evaluating the course of epileptic seizures and the results of the TMT over time. We performed the TMT twice with a 1-year interval for each patient with focal epilepsy. We performed multiple regression analyses with the first TMT scores as dependent variables and clinical features as independent variables. Next, we performed multivariate analysis of covariance (MANCOVA) to evaluate the difference between the first and second TMT scores for patients in each seizure prognosis group. We enrolled 132 adult patients in this study. Multiple regression analyses showed that longer active seizure periods were associated with worse first TMT-B performance (β = 0.318, P < 0.001) and B - A (β = 0.377, P < 0.001) and that the number of anti-seizure medicines was associated with worse first TMT-A performance (β = 0.186, P = 0.025). In addition, topiramate and zonisamide adversely affected TMT performance. MANCOVA showed an interaction between the prognosis of TMT-B performance and the seizure prognosis [F (2, 120) = 3.68, P = 0.028]. Sub-effect tests revealed that the second TMT-B performance improved only in the seizure improvement group [F (1, 10) = 10.07, P = 0.01]. Epileptic seizures were shown to be associated with both long-term and dynamic adverse effects on cognitive function evaluated with the TMT in adult patients with focal epilepsy. Seizure control is important for improving the cognitive function of patients with epilepsy; however, the potential adverse effects of polypharmacy and some anti-seizure medicines such as zonisamide and topiramate on cognitive function should be considered.

Peri-ictal heart rate changes in patients with epilepsy.

Heart rate (HR) changes associated with seizures are promising biomarkers in epilepsy. The aim of our study is to reveal possible HR changes in the peri-ictal period. Long-term video-EEG monitorization records of generalized and focal epilepsy patients were reviewed. HRs were calculated in the pre-ictal (2 min before the first seizure activity in EEG), ictal (the time from the first seizure activity on the EEG to the end of the seizure), and in the interictal period (at least 2 h before or 12 h after the seizure). Interictal, pre-ictal, and ictal HRs were compared with each other. In addition, it was investigated whether peri-ictal HR changes differ between generalized and focal seizure patients. Focal motor seizures were observed in 21, and generalized tonic-clonic seizures were observed in 18 of 39 (22 female and 17 male) patients studied. HRs in the pre-ictal and ictal periods were significantly higher than in the interictal period. This significant increase in HR was validated separately in both focal and generalized seizure groups and was not different between the two groups. Our study supports previous studies showing the presence of increased peri-ictal HR and also provides new insights by comparing focal and generalized motor seizures. We think that our findings may contribute to the development of early warning signs in epilepsy patients.

Event-Based Epileptic Seizure Detection with Stacked Convolutional Restricted Boltzmann Machine

Research indicates that around 1% of the global population experiences epileptic seizures, described as an undue neuronal discharge in the brain, which can significantly impact the quality of life for those affected. Children who experience frequent or prolonged seizures may experience lasting cognitive damage and psychological difficulties, and sudden seizures can pose a serious risk of injury or even death. Therefore, developing an accurate machine learning model to predict seizures is crucial. This study introduces an Event-based Stacked Convolutional Restricted Boltzmann Machine architecture that can detect ictal periods in EEG signals. The model was trained and evaluated on a publicly available dataset of EEG recordings from 24 pediatric patients, achieving a high prediction accuracy of 94.2%, with a mean prediction time of 19.62 min. The model's mean sensitivity and specificity rates were also comparable to those of state-of-the-art predictive models on the CHB-MIT dataset.