On the influence of prior information evaluated by fully Bayesian criteria in a personalized whole-brain model of epilepsy spread

PLoS Computational Biology, Год журнала: 2021, Номер 17(7), С. e1009129 - e1009129

Опубликована: Июль 14, 2021

Individualized anatomical information has been used as prior knowledge in Bayesian inference paradigms of whole-brain network models. However, the actual sensitivity to such personalized priors is still unknown. In this study, we introduce use fully criteria and leave-one-out cross-validation technique on subject-specific assess different epileptogenicity hypotheses regarding location pathological brain areas based a priori from dynamical system properties. The Virtual Epileptic Patient (BVEP) model, which relies fusion structural data individuals, generative model epileptiform discharges, self-tuning Monte Carlo sampling algorithm, infer spatial map across areas. Our results indicate that measuring out-of-sample prediction accuracy BVEP with informative enables reliable efficient evaluation potential degree regions. contrast, while using uninformative priors, are unable provide strong evidence about We also show correctly both functional components models differ individuals. information-theory approach study suggests patient-specific strategy for hypothesis testing epilepsy improve surgical outcomes.

Язык: Английский

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A unified physiological framework of transitions between seizures, sustained ictal activity and depolarization block at the single neuron level

Journal of Computational Neuroscience, Год журнала: 2022, Номер 50(1), С. 33 - 49

Опубликована: Янв. 15, 2022

Abstract The majority of seizures recorded in humans and experimental animal models can be described by a generic phenomenological mathematical model, the Epileptor. In this seizure-like events (SLEs) are driven slow variable occur via saddle node (SN) homoclinic bifurcations at seizure onset offset, respectively. Here we investigated SLEs single cell level using biophysically relevant neuron model including slow/fast system four equations. two equations for subsystem describe ion concentration variations fast delineate electrophysiological activities neuron. Using extracellular K + as variable, report that with SN/homoclinic readily when reaches critical value. patients models, also evolve into sustained ictal activity (SIA) depolarization block (DB), which parts dynamic repertoire Increasing to values found during status epilepticus DB, show SIA DB level. Thus, seizures, SIA, have been first identified network events, exist unified framework biophysical exhibit similar dynamics observed Author Summary: Epilepsy is neurological disorder characterized occurrence seizures. Seizures both macroscopic microscopic scales recordings. Experimental works allowed establishment detailed taxonomy models. We distinguish main types Phenomenological (generic) few parameters variables permit dynamical studies often capturing conditions. But they abstract parameters, making biological interpretation difficult. Biophysical on other hand, use large number due complexity systems represent. Because multiplicity solutions, it difficult extract general rules. present work, integrate approaches reduce sufficiently low-dimensional equations, thus maintaining advantages model. propose, level, different pathological block, activity.

Язык: Английский

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A Model for the Propagation of Seizure Activity in Normal Brain Tissue

eNeuro, Год журнала: 2022, Номер 9(6), С. ENEURO.0234 - 21.2022

Опубликована: Ноя. 1, 2022

Epilepsies are characterized by paroxysmal electrophysiological events and seizures, which can propagate across the brain. One of main unsolved questions in epilepsy is how epileptic activity invade normal tissue thus To investigate this question, we consider three computational models at neural network scale to study underlying dynamics seizure propagation, understand specific features play a role, relate them clinical or experimental observations. We both internal connectivity structure between neurons input properties our characterization. show that sometimes controlled while other instances, it lead itself produce activity, will further efferent networks. details architecture essential determine switch seizure-like regime. investigated nature instability involved particular found central role for inhibitory connectivity. propose probabilistic approach propagative/non-propagative scenarios, may serve as guide control using appropriate stimuli.

Язык: Английский

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Neural Field Models: A mathematical overview and unifying framework

Mathematical Neuroscience and Applications, Год журнала: 2022, Номер Volume 2

Опубликована: Март 19, 2022

Mathematical modelling of the macroscopic electrical activity brain is highly non-trivial and requires a detailed understanding not only associated mathematical techniques, but also underlying physiology anatomy. Neural field theory population-level approach to non-linear dynamics large populations neurons, while maintaining degree tractability. This class models provides solid theoretical perspective on fundamental processes neural tissue such as state transitions between different activities observed during epilepsy or sleep. Various anatomical, physiological, assumptions are essential for deriving minimal set equations that strike balance biophysical realism However, these always made explicit throughout literature. Even though (NFMs) first appeared in literature early 1970's, relationships them have been systematically addressed. may partially be explained by fact inter-dependencies often implicit non-trivial. Herein we provide review key stages history development contemporary uses this branch neuroscience. First, principles summarised discussion pioneering Wilson Cowan, Amari Nunez. Upon thorough models, then present unified framework which all can derived applying assumptions. We use i) derive Robinson, Jansen Rit, Wendling, Liley, Steyn-Ross, ii) make many significant inherited exist current

Язык: Английский

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A New Perspective in Epilepsy Classification: Applying the Taxonomy of Seizure Dynamotypes to Non-Invasive EEG and examining dynamical changes across sleep stages.

eNeuro, Год журнала: 2025, Номер unknown, С. ENEURO.0157 - 24.2024

Опубликована: Янв. 2, 2025

Epilepsy, a neurological disorder characterized by recurrent unprovoked seizures, significantly impacts patient quality of life. Current classification methods focus primarily on clinical observations and electroencephalography (EEG) analysis, often overlooking the underlying dynamics driving seizures. This study uses surface EEG data to identify seizure transitions using dynamical systems–based framework—the taxonomy dynamotypes—previously examined only in invasive data. We applied principal component independent analysis recordings from 1,177 seizures 158 patients with focal epilepsy, decomposing signals into components (ICs). The ICs were visually labeled for clear bifurcation morphologies, which then Bayesian multilevel modeling context factors. Our reveals that certain onset bifurcations (SNIC SupH) are more prevalent during wakefulness compared their reduced rate non-rapid eye movement (NREM) sleep, particularly NREM3. discuss possible implications our results approaches suggest additional avenues continue this exploration. Furthermore, we demonstrate feasibility automating process machine learning, achieving high performance identifying seizure-related classifying inter-spike interval changes. findings noise may obscure technical improvements could enhance detection accuracy. Expanding dataset incorporating long-term biological rhythms, such as circadian multiday cycles, provide comprehensive understanding improve decision-making. Significance statement Traditional focuses symptoms electrophysiological signs but overlooks dynamics. dynamotypes introduces novel computational approach links transition signatures these While previously recordings, extends non-invasive EEG. relationship between sleep stages integrating models reveal insights timing generalization, opening new pathways better diagnostics. Broader adoption is limited its labor-intensive visual inspection process. Here, potential automated classification, enabling scale larger cohorts.

Язык: Английский

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Can transsynaptic viral strategies be used to reveal functional aspects of neural circuitry?

Journal of Neuroscience Methods, Год журнала: 2020, Номер 348, С. 109005 - 109005

Опубликована: Ноя. 20, 2020

Язык: Английский

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Aspartate Metabolism Facilitates IL-1β Production in Inflammatory Macrophages

Frontiers in Immunology, Год журнала: 2021, Номер 12

Опубликована: Окт. 21, 2021

Increasing evidence support that cellular amino acid metabolism shapes the fate of immune cells; however, whether aspartate dictates macrophage function is still enigmatic. Here, we found metabolites in are depleted lipopolysaccharide (LPS) plus interferon gamma (IFN-γ)-stimulated macrophages. Aspartate promotes interleukin-1β (IL-1β) secretion M1 Mechanistically, boosts activation hypoxia-inducible factor-1α (HIF-1α) and inflammasome increases levels metabolism, such as asparagine. Interestingly, asparagine also accelerates signaling pathways production inflammatory cytokines from Moreover, supplementation augments macrophage-mediated responses mice piglets. These results uncover a previously uncharacterized role for directing polarization.

Язык: Английский

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Focal seizures are organized by feedback between neural activity and ion concentration changes

eLife, Год журнала: 2022, Номер 11

Опубликована: Авг. 2, 2022

Human and animal EEG data demonstrate that focal seizures start with low-voltage fast activity, evolve into rhythmic burst discharges are followed by a period of suppressed background activity. This suggests processes dynamics in the range tens seconds govern seizure evolution. We investigate associated complementing Hodgkin-Huxley mathematical model physical laws dictate ion movement maintain ionic gradients. Our biophysically realistic computational closely replicates electrographic pattern typical human characterized low voltage activity onset, tonic phase, clonic phase postictal suppression. study demonstrates, for first time silico, potential mechanism initiation inhibitory interneurons via initial build-up extracellular K + due to intense interneuronal spiking. The also identifies mechanisms may underlie key feature dynamics, is, progressive slowing down ictal towards end seizure. prediction specific scaling inter-burst intervals is confirmed recorded whole guinea pig brain vitro humans, suggesting observed termination hold across different species. results emphasize as elementary behind generation indicate targets new therapeutic strategies.

Язык: Английский

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Stimulation to probe, excite, and inhibit the epileptic brain

Epilepsia, Год журнала: 2023, Номер 64(S3)

Опубликована: Май 17, 2023

Direct cortical stimulation has been applied in epilepsy for nearly one century and experienced a renaissance given unprecedented opportunities to probe, excite inhibit the human brain. Evidence suggests can increase diagnostic therapeutic utility patients with drug-resistant epilepsies. However, choosing appropriate parameters is not trivial issue, which further complicated by fact that characterized complex brain state dynamics. In this article derived from discussions at ICTALS 2022 conference, we succinctly review literature on acutely chronically epileptic localization, monitoring, purposes. particular, discuss how used probe excitability, evidence usefulness of trigger stop seizures, applications stimulation, finally are impacted Although research advanced considerably over past decade, there still significant hurdles optimize use technique. For example, it remains unclear what extent short timescale biomarkers predict long-term outcomes these add information already existing passive EEG recordings. Further questions include closed loop offers advantages open optimal timescales may be, whether biomarker-informed lead seizure freedom. The ultimate goal bioelectronic medicine just seizures but rather cure its comorbidities.

Язык: Английский

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Sleep, oscillations, and epilepsy

Epilepsia, Год журнала: 2023, Номер 64(S3)

Опубликована: Май 25, 2023

Abstract Sleep and wake are defined through physiological behavioral criteria can be typically separated into non‐rapid eye movement (NREM) sleep stages N1, N2, N3, rapid (REM) sleep, wake. states not homogenous in time. Their properties vary during the night day cycle. Given that brain activity changes as a function of NREM, REM, cycle, seizures more likely to occur or at specific time? More generally, what is relationship between sleep–wake cycles epilepsy? We will review examples from clinical data results experimental models, focusing on diversity heterogeneity these relationships. use top‐down approach, starting with general architecture followed by oscillatory activities, ending ionic correlates selected for illustrative purposes, respect interictal spikes. The picture emerges complexity; disruption pathological epileptic activities emerge reorganized circuits. That different circuit alterations across patients models may explain why timing cycle patient‐specific.

Язык: Английский

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