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Pathophysiology of Neocortical Epileptic Seizures

  • Igor Timofeev

Introduction and Definitions

Neocortical seizures are seizures that are primarily generated within neocortex. Seizures for which primary foci are located in other brain structures and secondarily project to neocortex are not considered to be neocortical. The origin of epileptic seizures accompanying various types of epileptic fits is hotly debated. Neocortical seizures are primarily focal and often become secondarily generalized tonic-clonic seizures (Crunelli and Leresche 2002). Electrographically, these seizures are most oftenly composed of spike-wave/polyspike-wave (SW/PSW) electroencephalographic (EEG) discharges at 1.0–2.5 Hz and runs of fast spikes at 7–16 Hz ( Fig. 27-1). However, on some occasions, neocortical seizures are characterized by SW complexes at approximately 3 Hz. Spontaneously occurring SW complexes at 1–2.5 Hz and fast runs at 7–16 Hz develop without discontinuity from slow (mainly 0.5–0.9 Hz) cortically generated oscillations (Steriade and Contreras 1995). At the...

Keywords

Cortical Dysplasia Mesial Temporal Lobe Epilepsy Fire Action Potential Idiopathic Generalize Epilepsy Frontal Lobe Epilepsy 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgment

Research in my laboratory is supported by CIHR, NSERC, NIH and FRSQ. I express my deepest gratitude to my long-term collaborators: Dr. M. Steriade, M. Bazhenov and T. Sejnowski, as well as to numerous trainees and technicians that contributed to research activities by my laboratory during several last years.

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Copyright information

© Springer-Verlag London Limited 2010

Authors and Affiliations

  • Igor Timofeev
    • 1
  1. 1.CRULRGUniversité LavalQuébecCanada

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