[Analysis of human EEG spectra in a state of relative and "operative rest" according to A. A. Ukhtomskii].

The analysis of EEG in 40 healthy subjects showed that power spectra, coherence and phase spectra strongly vary in different subjects and that their spatial distribution among cortical areas bears individual properties. General characteristics of the spectra and mean levels of EEG coherence are stable, but details of power spectra, coherence and phases in healthy subjects are very unstable even within short time intervals. In the process of developing in the subject of a stable, ordered by experimenter state of a strained expectation of the signal to immediate activity--of "operative rest", according to A. A. Ukhtomsky--a uniform for all subjects structure of connections is shaped in frontal-central cerebral parts, which is manifested in a specific pattern of coherence spectrum.