[Origin of the electroencephalogram].

An attempt is made to estimate the contribution of the activity of each cortical layer of rabbit's brain and subcortical structure in EEG formation. It has been shown that the main generator layers of spontaneous EEG are the I layer--the layer of apical dendrites and the V--the layer of pyramidal neuron somas. To perform a quantitative estimation of passive penetration of the electric fields from deep-seated structures, chiefly from the hippocampus, biopotentials studied were recorded from I, V cortex layers and hippocampus simultaneously, the cortex being disengaged by the method of propagating depression. Significant suppression of surface-activity of the motor cortex was achieved with its preservation in the hippocampus.