PRACTICA OTO-RHINO-LARYNGOLOGICA
Vol. 100 No. 10 October 2007
Functional Linkages between Semicircular-Ocular
Reflex and Otolith-Ocular Reflex
Izumi Koizuka
(St. Marianna University School of Medicine)
Vestibulo-ocular reflex (VOR) generates smooth eye movements that are compensatory for head movements to ensure gaze stabilization during head rotations. VOR consists of the semicircular-ocular reflex (ScOR) and the otolith-ocular reflex (OOR). The ScOR induces eye movements that compensate for rotations of the head, whereas the OOR produces eye movements that compensate for linear head movements, so that visual images remain relatively steady on the retina.
During normal visual-vestibular interaction, cooperation between the VOR and vision result in stabilization of the retinal image. Adaptive VOR recalibration occurs whether visual-vestibular mismatch arises through the manipulation of visual feedback during head movement or by lesion-induced modification of vestibular input. Current models of the VOR contain separate gain elements for the ScOR and the OOR.
In this article, we describe our experiments to investigate the plasticity of the ScOR and OOR using OVAR and a linear sled to clarify visual-vestibular interaction. We also further addressed the relationship between adaptive change in the ScOR and the OOR.
Key words : functional linkages, semicircular-ocular reflex, otolith-ocular reflex, plasticity