Rhythmic processes in the cerebral cortex.

A differential equation describing the electroencephalogram (EEG) is deduced based on the data on the structure of the brain cortex and the conceptions about a recurrent inhibition. This equation allows the study of a number of essential electrophysiological phenomena: the philogenetic differences in the frequency composition of the EEG, the shift of the EEG spectrum to higher frequencies upon excitation of the cortex, the lowering of the EEG rhythms and changes in cell reaction on deafferentation of the cortex, the identity in the spectra of a spontaneous EEG and evoked responses. A possible mechanism for the onset of epileptic activity is proposed.