[The individual EEG reactions of healthy subjects to mutually antagonistic noradrenotropic influences].

Pharmacogenous shifts in EEG spectral density induced by mutually antagonistic noradrenotropic influences (pairs sydnocarb-obsidan and sydnocarb-sonapax) were compared in each of four subjects by means of factor and discriminant analysis. Narrow-band oppositely directed reactions were revealed almost in all classical EEG diapasons in a range of 0.5-30 Hz. Incidence of such reactions, their expression and generalization made it possible to recognize the states, induced by each of the drugs, and EEG reactions to placebo in every subject with high significance. The most pronounced oppositely directed shifts were observed in the band of approximately 20-24 Hz. They were revealed in all the subjects and had an accent of expression in parietal-central areas. Sydnocarb increased the spectral density in this band, obsidan and sonapax decreased it. The obtained data point to the possibility of application of EEG density change in the band of 20-24 Hz over the right parietal area as an EEG marker of the level of activation of noradrenergic neurotransmitter system.