Neural Computing and Applications

, Volume 20, Issue 6, pp 825–833 | Cite as

Clustering of entropy topography in epileptic electroencephalography

  • Nadia Mammone
  • Giuseppina Inuso
  • Fabio La Foresta
  • Mario Versaci
  • Francesco C. Morabito
EANN 2009

Abstract

Epileptic seizures have been considered sudden and unpredictable events for centuries. A seizure seems to occur when a massive group of neurons in the cerebral cortex begins to discharge in a highly organized rhythmic pattern, then it develops according to some poorly described dynamics. As proved by the results reported by different research groups, seizures appear not completely random and unpredictable events. Thus, it is reasonable to wonder when, where and why the epileptogenic processes start up in the brain and how they result in a seizure. In order to detect these phenomena from the very beginning (hopefully minutes before the seizure itself), we introduced a technique, based on entropy topography, that studies the synchronization of the electric activity of neuronal sources in the brain. We tested it over 3 EEG data set from patients affected by partial epilepsy and 25 EEG recordings from patients affected by generalized seizures as well as over 40 recordings from healthy subjects. Entropy showed a very steady spatial distribution and appeared linked to the brain zone where seizures originated. A self-organizing map-based spatial clustering of entropy topography showed that the critical electrodes shared the same cluster long time before the seizure onset. The healthy subjects showed a more random behaviour.

Keywords

Electroencephalography Renyi’s entropy Epilepsy SOM 

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Copyright information

© Springer-Verlag London Limited 2011

Authors and Affiliations

  • Nadia Mammone
    • 1
  • Giuseppina Inuso
    • 1
  • Fabio La Foresta
    • 1
  • Mario Versaci
    • 1
  • Francesco C. Morabito
    • 1
  1. 1.Mediterranean University of Reggio CalabriaReggio CalabriaItaly

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