[Levels of slow bioelectric organization of the human brain].

A certain relation between spontaneous pattern and responses to tests of the slow electric processes (SEP) and the order of value of the measured potential was revealed within a single subcortical area of the human brain. A close relation between the constant component (within the range of 110 to 1 mV) and the markedness and character of clinical signs, was observed. A reproducible SEP response to psychological or motor tests was revealed within the ranges of the SEP variable component (from 1000 to 100 mcV and from 5-10 to 50-100 mcV) regarded, respectively, as the ranges of moderate and weak bioelectric signal. The subcortical equivalent and changes of the reproducible pattern in response to meaningless trigrams and words were only observed within the weak signal range. Existence of certain individual ranges of the SEP constant component was revealed in separate neuronal-glial populations. The data obtained show physiological and informative variability of SEP within a single neuronal-glial population in different ranges of the recorded potential's value, which may provide premises for elucidating neurophysiological mechanisms, of different levels for regulation of the links constituting cerebral systems for maintenance of various activities.