Reducing Artifacts in TMS-Evoked EEG

  • Juan José Fuertes
  • Carlos M. Travieso
  • A. Álvarez
  • M. A. Ferrer
  • J. B. Alonso
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6076)


Transcranial magnetic stimulation induces weak currents within the cranium to activate neuronal firing and its response is recorded using electroencephalography in order to study the brain directly. However, different artifacts contaminate the results. The goal of this study is to process these artifacts and reduce them digitally. Electromagnetic, blink and auditory artifacts are considered, and Signal-Space Projection, Independent Component Analysis and Wiener Filtering methods are used to reduce them. These last two produce a successful solution for electromagnetic artifacts. Regarding the other artifacts, processed with Signal-Space Projection, the method reduces the artifact but modifies the signal as well. Nonetheless, they are modified in an exactly known way and the vector used for the projection is conserved to be taken into account when analyzing the resulting signals. A system which combines the proposed methods would improve the quality of the information presented to physicians.


Transcranial magnetic stimulation electroencephalogram artifact electromagnetic blink auditory 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Juan José Fuertes
    • 1
  • Carlos M. Travieso
    • 2
  • A. Álvarez
    • 2
  • M. A. Ferrer
    • 2
  • J. B. Alonso
    • 2
  1. 1.Instituto Interuniversitario de Investigación en Bioingeniería y Tecnología Orientada al Ser, HumanoUniversidad Politécnica de ValenciaValenciaEspaña
  2. 2.Dpto. de Señales y ComunicacionesUniversidad de Las Palmas de Gran Canaria, Centro Tecnológico para la Innovación en ComunicacionesLas Palmas de Gran CanariaEspaña

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