Interaction Between The Utricles And The Horizontal Semicircular Canals II. Unilateral Selective Section of the Horizontal Ampullar and the Utricular Nerve, followed by Tilting around the Longitudinal Axis

Abstract

Selective unilateral section of the horizontal ampullar nerve and the utricular nerve was performed. By tilting the animals around their longitudinal axis, the alterations in the horizontal nystagmus were studied. It was shown that these alterations were released from the intact utricle. An increase in utricular activity due to tilting toward the operated ear resulted in a positive triggering of the nystagmus from the ipsilateral horizontal semicircular canal. A decrease in its activity by tilting toward the nonoperated ear inhibited the nystagmus. The cause of these findings is discussed.