The sensitivity of instantaneous coherence for considering elementary comparison processing. Part II: Similarities and differences between EEG and MEG coherences

The EEG (electroencephalogram) coherence depends on EEG deviation type. A h igh level of sensitivity of instantaneous coherence for investigating eleme ntary cognitive tasks could be shown in the case of unipolar reference (ear lobe reference). In order to validate of this result the same investigatio ns were performed for MEG (magnetoencephalogram) coherence, where EEG and M EG were measured simultaneously. A strong correlation between time interval s with high EEG and MEG coherence could be shown. The equivalence of the se nsitivity of EEG and MEG coherence for the description of the dynamic behav iour of information processing and the distinction between different elemen tary cognitive tasks is proven statistically. (C) 1999 Elsevier Science B.V . All rights reserved.