Lesion of the nodulus and ventral uvula abolish steady-state off-vertical
axis otolith response.
Angelaki, Dora E., and Bernhard J. M. Hess.
Dept. of Surgery (Otolaryngology), University of Mississippi Medical
Center, Jackson MS.
APStracts 2:0053N, 1995.
SUMMARY AND CONCLUSIONS
During rotations that dynamically activate utricular and saccular primary
afferents, the otolith system centrally detects the amplitude and direction of
rotation of the head in space. This property is experimentally manifested as a
steady-state compensatory nystagmus during constant velocity off-vertical axis
rotations. The computational, physiological and anatomical details of this
computation remain presently unknown. Here, we report that surgical
inactivation of the cerebellar nodulus and ventral uvula abolished the ability
of the otolith system to generate steady-state nystagmus during constant
velocity rotation and to improve the dynamics of the VOR during low frequency
sinusoidal oscillations about off-vertical axes in rhesus monkeys. These
results suggest that the cerebellar nodulus and/or ventral uvula comprise part
of the neural substrate that is involved in these computations.
Received 7 December 1994; accepted in final form 19 January 1995.
APS Manuscript Number J767-4.
Article publication pending J. Neurophysiol.
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 3 April 1995.