Comparison of the quantitative characteristics of ultraslow phasic activity of the brain and the EEG in the states of quiet wakefulness with the eyes open and closed

Quantitative statistical estimates of changes in ultraslow phasic electrical activity of the brain (in the range 0.05-0.5 Hz) and the EEG (1.5-50 Hz) with time were compared in the basic (reference) states of quiet wakefulness with the eyes open and closed (EO and EC, respectively). In both states, the changes in the power and coherence of ultraslow phasic activity and the EEG had similar trends; however, the topographic patterns of the changes were different. The obtained data confirm the assumption on different structural and functional bases of the EEG and ultraslow phasic activity of the brain and indicate polysystemic differences between the EO and EC states.