[Evoked potentials in the auditory cortex with systematic use of standard series of stimuli on the internal...

Standard series of short electrical stimuli of the medial geniculate body were systematically applied to dogs with chronically implanted electrodes. Gradual formation was observed of a dependence of amplitudes of averaged EPs in the auditory cortex on the consecutive place of the stimulus in the series. This points to the existence in the dog's central nervous system of an elementary form of counting not only adequate signals, as has been previously shown, but also electrical stimuli of the thalamic nucleus. In contrast to what was observed in response to clicks, the EPs amplitude of MGB electrical stimulations increases by the middle of the series and diminishes by its end. It has been assumed that the cortical level of the analyser to which the stimulation was applied, suffices for the formation of the above phenomenon.