The effect of passive rotation in horizontal plane on perception of moving sound images

Abstract

During the standard step examination in the rotary chair Nydiag 200 the authors, alongside with the rotary nystagmus, registered the evaluation of acoustic images motion direction. During the initial 20 seconds of the patient rotation, the patient, reliably more frequently than at rest, evaluated the acoustic images moving to the right as those moving to the left. The changes of localization were made in the direction opposite to that of rotation. No reliable changes have been found during the reverse movement. During the initial 20 seconds after patient rotation to the left the direction of the change of localization coincided with the movement direction. The revealed asymmetry of localization of the moving acoustic images during the rotation in a horizontal plane supports observations of Lewald and Karnath (2001) about asymmetrical effect of rotation to the right and to the left on localization of immobile acoustic images and brings up a question about the role of otolith asymmetry in the interactions of vestibular and auditory sensory systems.