Abstract
Electrocochleographical studies were performed with the active electrode on the ear-drum. A close correspondence of the thresholds of 8th nerve action potentials (AP) and the subjective hearing thresholds was observed. The input-output curves of AP demonstrated L and H slopes. In persons with complete unilateral hearing losses no responses could be recorded from the deaf ear either to ipsilateral or contralateral sound stimulation. The effects of contralateral stimulation on AP were studied in persons with large interaural threshold differences. Two types of influences were described, the first being inhibitory and the second facilitatory. It has been suggested that the first effect depends on the reflex activity of the middle ear muscles, whereas the second effect should be attributed to the activity of auditory feed-back controlling system.