Initiation and Spread of Seizures in Man: Analytical Methods for Monitoring Seizures

  • Terrance M. Darcey


Electrical recordings of the spontaneous seizure are perhaps the most important source of information regarding seizure initiation and propagation. While the discharges that occur may be obvious, their interpretation is sometimes very difficult. This paper reviews computational procedures that have been devised to analyze initiation and propagation patterns of focal epileptic seizures via EEG measurements with macroscopic electrodes. Thus far, most efforts have been rather straightforward applications of signal processing methods such as signal detection, digital filtering, auto-spectral and cross-spectral analysis. Generally speaking, these methods invoke minimal assumptions regarding seizure mechanisms, and might be best described as computer aids to the objective, accurate measurement of the occurrence or interrelationship of epileptiform signals. The need for computer-aided analysis is especially evident when such information is not forthcoming from visual inspection, for example [1] when the signals of interest are obscured by noise or artifacts due to the recording process or behavioral seizure, [2] when there is rapid and/or complicated propagation of the discharge, [3] when the recording sites are sufficiently remote from the site of epileptiform activity to require some means of signal enhancement or localization of the signal source, or [4] when the relationship of simultaneously occurring signals is important.


Seizure Activity Partial Coherence Time Delay Estimation Seizure Discharge Seizure Episode 
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.


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Copyright information

© Springer Science+Business Media New York 1988

Authors and Affiliations

  • Terrance M. Darcey
    • 1
    • 2
  1. 1.Neurology Service and Neuropsychology LaboratoryVeterans Administration Medical CenterWest HavenUSA
  2. 2.Department of NeurologyYale University School of MedicineNew HavenUSA

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