The novelty value of the combined use of electroencephalography and transcranial magnetic stimulation for neuroscience research.
Electroencephalographic (EEG) responses measured simultaneously with transcranial magnetic stimulation (TMS) have opened a new window into the human nervous system. The combined use of TMS and EEG (TMS-EEG) provides a means for the detailed study of the reactivity of any cortical region in the intact brain; also the reactivities of non-motor cortical areas related with higher-order functions are now appreciable. A recent epochal finding concerning cortical reactivity is that neuronal activation is induced with remarkably low stimulation intensities. This knowledge is significant when optimizing experimental set-ups for maximal patient safety. Stimulation of different cortical areas evokes different patterns of remote EEG activity, confirming the viability of TMS-EEG for the study of corticocortical connections. In this review, we expand on these and other notable findings related with TMS-EEG. We discuss the possibilities of the technique for the study of cortical reactivity and connectivity. We show that TMS-EEG allows the study of interhemispheric connections with high spatiotemporal specificity and the assessment of cortical reactivity with excellent sensitivity.
Komssi
Soile
S
HUS Medical Imaging Center, University of Helsinki, PO Box 340, FIN-00029 HUS, Finland. soile.komssi@hus.fi
Kähkönen
Seppo
S
D035843:Biomedical Research; D001921:Brain / Q000502:physiology*; D004569:Electroencephalography / Q000379:methods*; D006801:Humans; D009488:Neurosciences / Q000379:methods*; D050781:Transcranial Magnetic Stimulation / Q000379:methods*