Short-latency Primate Vestibulo-Ocular Responses During Translation. Dora E. Angelaki & M. Quinn McHenry. Dept. of Surgery (Otolaryngology), University of Mississippi Medical Center, Jackson MS.
APStracts 6:0303N, 1999.
Short lasting, transient head displacements and near target fixation were used to measure the
latency and early response gain of vestibularly evoked eye movements during lateral and fore-aft
translations in rhesus monkeys. The latency of the horizontal eye movement elicited during
lateral motion was 11.9 ±5.4 ms. Viewing distance-dependent behaviour was seen as early as the
beginning of the response profile. For fore-aft motion, latencies were different for forward and
backward displacements. Latency averaged 7.1 ±9.3 ms during forward motion (same for both
eyes) and 12.5 ±6.3 ms for the adducting eye (e.g., left eye during right fixation) during
backward motion. Latencies during backward motion were significantly longer for the abducting
eye (18.9 ±9.8 ms). Initial acceleration gains of the two eyes were generally larger than unity but
asymmetric. Specifically, gains were consistently larger for abducting than adducting eye
movements. The large initial acceleration gains tended to compensate for the response latencies
such that the early eye movement response approached, albeit consistently incompletely, that
required for maintaining visual acuity during the movement. These short-latency vestibulo-ocular
responses could complement the visually-generated optic flow responses that have been shown to exhibit much longer latencies.
Received 12 May 1999; accepted in final form 15 June 1999.
APS Manuscript Number J398-9.
Article publication pending Journal of Neurophysiology.
ISSN 1080-4757 Copyright 1999 The American Physiological Society.
Published in APStracts on 28 July 1999