Effects of roll tilt on the direction of vertical postrotatory nystagmus in cats.

摘要

The rotation axis of horizontal postrotatory nystagmus (PRN) changes as the head is tilted, so that it becomes directed toward gravity (spatial reorientation). Here, we examined the vertical PRN orientation during roll tilt in cats. Unlike the case in horizontal PRN, in vertical PRN no significant cross-coupled components emerged to reorient the eyes toward gravity. Our results indicate that otolith input contributes differently to horizontal VOR than to vertical VOR.