Signal Processing of EEG: Evidence for Chaos or Noise. An Application to Seizure Activity in Epilepsy
The EEG is an important signal for the diagnosis of functional disturbances of the brain, and in particular, of epilepsy. The non-linear dynamical analysis of EEG signals recorded during seizure activity in comparison with on-going signals allowed us to formulate a hypothesis about the generation of epileptic activity. According to this model, epilepsy should be envisaged as a dynamical disease of neuronal networks, that may exhibit different types of attractors, i.e., may present bifurcations. One of these attractors is characterized by the generation of irregular oscillations, typical of epileptic seizures.
KeywordsLyapunov Exponent Neuronal Network Epileptic Seizure Correlation Dimension Seizure Activity
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