[Effect of isorhythmic and heterorhythmic stimulation of the septum and mammillary bodies on the EEG of the rabbit].

The influence was studied of combined isorhythmic and heterorhythmic stimulations of the septum and mammillar bodies (S + MB) on spatial organization of brain biopotentials and on the speed of acquisition of defensive conditioned reflex (CR) to light. Analysis of the effect of the isorhythmic stimulation on learning showed that CR elaboration was impeded and in some situations was even impossible. Apparently, isorhythmic S + MB stimulation did not prevent closing of the temporary connection but disturbed CR realization. At simultaneous heterorhythmic electric S + MB stimulations, in most cases cortical parts reproduced only one rhythmic process corresponding to the frequency of the septal stimulation. Combined heterorhythmic S + MB stimulation promoted successful defensive CR elaboration though prolonged action of such stimulations led to development of neurotic state in animals.