Abstract
Specific properties of the electrical activity of the auditory system were studied on unanesthetized curarized cats, and the following results were obtained.
1) The electrical activity level of the auditory system changed independently from the other neocortical areas and paleo-and archicortices.
2) Tone stimulus of adequate intensity produced the localized activation in the auditory area.
3) Low voltage fast activity in the auditory area occurred by high frequency electrical stimulation of the medial geniculate body.
4) The spontaneous spindle bursts of the auditory area were frequently accompanied by the spindle bursts in the ipsilateral medial geniculate body. In the spindle stage of EEG, the spindle bursts were induced by click both in the auditory area and medial geniculate body. The pattern of the induced spindle bursts was similar to that of the spontaneous spindle bursts.
5) The induced spindle bursts in the auditory area by single shock stimulation of the ipsilateral medial geniculate body, and conversely, the spindle bursts in the medial geniculate body induced by single shock stimulation of the auditory area were observed. The induced spindle bursts in the auditory area and the spindle bursts in the sensori-motor cortex induced by single shock stimulation of the caudate nucleus did not interfere each other.
6) The spindle-like discharges in the midbrain reticular formation sometimes occurred together with the spontaneous spindle bursts in the auditory area and medial geniculate body.
