Model for the Translational Vestibuloocular Reflex (VOR)

Departments of 1 Physiology and 2 Otolaryngology, University of Toronto, Toronto, Ontario M5S 1A8, Canada Musallam, Wissam S. and R. D. Tomlinson. Model for the Translational Vestibuloocular Reflex (VOR). J. Neurophysiol. 82: 2010-2014, 1999. The function of the translational vestibuloocular reflex (tVOR) and the angular vestibuloocular reflex (aVOR) is to stabilize images on the retina during translational and rotational motion, respectively. It has generally been assumed that these two reflexes differ in their central processing because they differ significantly in their primary afferent behavior and characteristics at the motor level. So far, models of the tVOR have focused on the type of processing that the primary afferent signal must undergo before reaching the neural integrator. Here, we propose a model that does not require any prefiltering. It is known that the eye plant requires signals in phase with velocity and position. We propose that the velocity signal is obtained directly from the neural integrator, whereas the position signal is obtained directly from the primary afferents synapsing onto the oculomotor nuclei. This design proved sufficient to simulate eye movements in response to translational motion.