Extracranial Slow Magnetic Field Changes during Epileptic Activity

  • Jürgen Vieth
  • Peter Schüler
  • Gunnar Sack
  • Oliver Ganslandt
  • Wolfgang Dratz
  • Horst Fischer
  • Uwe Grimm
Part of the Brain Dynamics book series (BD)

Abstract

Current flow inside neurons creates weak magnetic fields that can be measured outside the head using a SQUID (superconducting quantum interference device) sensor. By analogy with the electroencephalogram (EEG), the recording of magnetic fields of the head is called a magnetoencephalogram (MEG). Generally the MEG and the EEG are recorded by using a lower frequency limit, mainly at 1 Hz or 0.1 Hz. But when the signal pathway is direct coupled (DC), no lower frequency limit exists, and slow and very slow signal changes are measurable.

Keywords

Epileptic Patient Complex Partial Seizure Epileptic Activity Superconducting Quantum Interference Device Lower Frequency Limit 
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 1993

Authors and Affiliations

  • Jürgen Vieth
  • Peter Schüler
  • Gunnar Sack
  • Oliver Ganslandt
  • Wolfgang Dratz
  • Horst Fischer
  • Uwe Grimm

There are no affiliations available

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