PLoS ONE (Sep 2010)

Temporo-spatial dynamics of event-related EEG beta activity during the initial contingent negative variation.

  • Thomas Fischer,
  • Robert Langner,
  • Kersten Diers,
  • Burkhard Brocke,
  • Niels Birbaumer

DOI
https://doi.org/10.1371/journal.pone.0012514
Journal volume & issue
Vol. 5, no. 9
p. e12514

Abstract

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In the electroencephalogram (EEG), early anticipatory processes are accompanied by a slow negative potential, the initial contingent negative variation (iCNV), occurring between 500 and 1500 ms after cue onset over prefrontal cortical regions in tasks with cue-target intervals of about 3 s or longer. However, the temporal sequence of the distributed cortical activity contributing to iCNV generation remains unclear. During iCNV generation, selectively enhanced low-beta activity has been reported. Here we studied the temporal order of activation foci in cortical regions assumed to underlie iCNV generation using source reconstruction of low-beta (13-18 Hz) activity. During the iCNV, elicited by a cued simple reaction-time task, low-beta power peaked first (750 ms after cue onset) in anterior frontal and limbic regions and last (140 ms later) in posterior areas. This activity occurred 3300 ms before target onset and provides evidence for the temporally ordered involvement of both cognitive-control and motor-preparation processes already at early stages during the preparation for speeded action.