R.A. Tolmacheva- Post-graduate Student, V.A. Kotel’nikov IRE RAS (Moscow)
Y.V. Obukhov – Dr.Sc. (Phys.-Math.), Senior Research Scientist, V.A. Kotel’nikov IRE RAS (Moscow)
Widely used methods of assessing coherence of electroencephalogram signals (EEG) have well-known drawbacks associated with the averaging of the evaluation of coherence in non-overlapping time periods and wide frequency ranges and associated with the influence of the assessment of amplitude modulation and noise. The report suggests a new approach to the evaluation of phase coherence of EEG signals, consisting in the calculation of the phases of signals at the points of the ridges of their wavelet spectrograms. These points, under certain conditions, have property of stationary of the phase. In this case, it is not required to conduct mentioned averaging. Evaluations of inter-channel phase coherence of EEG signals using cognitive tests are considered.
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