• Corpus ID: 18749467

The evolution with time of the spatial distribution of the largest Lyapunov exponent on the human epileptic cortex

  title={The evolution with time of the spatial distribution of the largest Lyapunov exponent on the human epileptic cortex},
  author={Leonidas D. Iasemidis and J. Chris Sackellares},
The topic of this presentation is the investigation of the epileptic human brain as a nonlinear system that undergoes a phase transition (epileptic seizure). The estimated values of the largest Lyapunov exponent L over time indicated a more chaotic state postictally than ictally or preictally. The start of a seizure corresponds to a simultaneous drop in the values of L at the focal electrode sites. The observed slow cyclic variations in the temporal Lyapunov profiles imply attempts of the… 
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Low-dimensional chaos in an instance of epilepsy.
Using a time series obtained from the electroencephalogram recording of a human epileptic seizure, we show the existence of a chaotic attractor, the latter being the direct consequence of the
Temporal and spatial distribution of intracellular potentials during generation and spread of epileptogenic discharges.
This chapter addresses the characteristics and spatial distribution of intracellular potentials, the spread of paroxysmal depolarization shifts (PDSs) through the cortex, the extracellular field
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Physical and numerical experiments show that deterministic noise, or chaos, is ubiquitous. While a good understanding of the onset of chaos has been achieved, using as a mathematical tool the
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It is not always possible to resolve the dimension of an attractor from a finite data set. The number of data points required depends on the structure of the attractor, the distribution of points on
Interictal--ictal transition in the feline penicillin epileptogenic focus.
  • I. Sherwin
  • Medicine
    Electroencephalography and clinical neurophysiology
  • 1978
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