Epilepsies as Dynamical Diseases of Brain Systems: Basic Models of the Transition Between Normal and Epileptic Activity

  title={Epilepsies as Dynamical Diseases of Brain Systems: Basic Models of the Transition Between Normal and Epileptic Activity},
  author={Fernando Lopes Da Silva and Wouter Blanes and Stiliyan N. Kalitzin and Jaime Parra and Piotr Suffczynski and Demetrios N. Velis},
Summary:  Purpose: The occurrence of abnormal dynamics in a physiological system can become manifest as a sudden qualitative change in the behavior of characteristic physiologic variables. We assume that this is what happens in the brain with regard to epilepsy. We consider that neuronal networks involved in epilepsy possess multistable dynamics (i.e., they may display several dynamic states). To illustrate this concept, we may assume, for simplicity, that at least two states are possible: an… 

Epilepsy as a dynamic disease of neuronal networks.

Design Principle for a Population-Based Model of Epileptic Dynamics

A design principle is suggested to generate the complex rhythmic evolution of tonic-clonic epileptic seizures in a neural population approach by starting from a simple neuronal oscillator with a single nonlinearity.

On the nature of seizure dynamics.

A taxonomy of seizures based on first principles is established and only five state variables linked by integral-differential equations are sufficient to describe the onset, time course and offset of ictal-like discharges as well as their recurrence.

A new description of epileptic seizures based on dynamic analysis of a thalamocortical model

The results suggest that the jump phenomenon due to the brain nonlinear resonance can be responsible for the transitions between ictal and interictal states.

Epilepsy as a dynamical disorder orchestrated by epileptogenic zone: a review

The short- and long-term effects of recurrent epileptiform discharge on neural circuits, involving the regulation of connection weights and network topology is discussed, suggesting that the excitability of regions connected with EZ may be enhanced, leading to frequent transitions from normal to epileptic states.

Chance and risk in epilepsy.

The canonical randomness of seizures is being reconsidered in light of cycles of brain activity discovered through chronic EEG, which motivates development of next-generation devices to track more closely fluctuations in epileptic brain activity that determine time-varying seizure risk.

Computational modelling of epileptic seizure dynamics and control

This study shows that microscopic features, like gap-junction dynamics, may be connected to macroscopic phenomena like HFOs and seizures by across-scale computational models.

Pathological pattern formation and cortical propagation of epileptic seizures

The model and observational results agree in two important respects during seizure: the average frequency of maximum power, and the speed of spatial propagation of voltage peaks, which suggests that seizing activity on the human cortex may be understood as an example of pathological pattern formation.



Epileptic seizures can be anticipated by non-linear analysis

It is demonstrated that in most cases, seizure onset could be anticipated well in advance (between 2–6 minutes beforehand), and that all subjects seemed to share a similar 'route' towards seizure.

Spatio-temporal dynamics of the primary epileptogenic area in temporal lobe epilepsy characterized by neuronal complexity loss.

Time dependencies in the occurrences of epileptic seizures

Phase space topography and the Lyapunov exponent of electrocorticograms in partial seizures

Electrocorticograms from 16 of 68 chronically implanted subdural electrodes, placed over the right temporal cortex in a patient with a right medial temporal focus, were analyzed and a methodology for detecting prominent spikes in the ECoG was developed.

Characterization of state transitions in spatially distributed, chaotic, nonlinear, dynamical systems in cerebral cortex

  • W. Freeman
  • Biology
    Integrative physiological and behavioral science : the official journal of the Pavlovian Society
  • 1994
Spatial phase gradients in the EEG are useful for identifying EEG segments in a sequence of state transitions in response to sensory input, and give strong reason to postulate that the mechanism for the construction of these sequences of patterns is a dynamical system operating in a chaotic domain.

High‐frequency oscillations in human brain

Two similar types of high‐frequency field oscillations recorded from the entorhinal cortex and hippocampus of patients with mesial temporal lobe epilepsy are described, which are found in the epileptogenic region and may reflect pathological hypersynchronous population spikes of bursting pyramidal cells.

Cellular mechanisms of a synchronized oscillation in the thalamus.

Reduction of gamma-aminobutyric acidA (GABAA) receptor-mediated inhibition markedly enhanced GABAB inhibitory postsynaptic potentials in relay cells and subsequently generated a slowed and rhythmic population activity resembling that which occurs during an absence seizure.

Inhibition-based rhythms: experimental and mathematical observations on network dynamics.