Naso-occipital vestibulo-ocular reflex responses in normal subjects

2000 ◽  
Vol 19 (2) ◽  
pp. 43-47 ◽  
Author(s):  
R.D. Tomlinson ◽  
R. Cheung ◽  
A. Blakeman
Keyword(s):  
Normal Subjects ◽  
Reflex Responses ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex

Effects of adaptation of vestibulo-ocular reflex function on manual target localization

2000 ◽  
Vol 10 (2) ◽  
pp. 75-86 ◽  
Author(s):  
Jacob J. Bloomberg ◽  
Lauren A. Merkle ◽  
Susan R. Barry ◽  
William P. Huebner ◽  
Helen S. Cohen ◽  
...  
Keyword(s):  
Adaptive Modulation ◽  
Normal Subjects ◽  
Target Localization ◽  
Whole Body ◽  
Spatial Coding ◽  
Ocular Reflex ◽  
Manual Responses ◽  
Vestibular Cues ◽  
Before And After ◽  
Vestibulo Ocular Reflex

The goal of the present study was to determine if adaptive modulation of vestibulo-ocular reflex (VOR) function is associated with commensurate alterations in manual target localization. To measure the effects of adapted VOR on manual responses we developed the Vestibular-Contingent Pointing Test (VCP). In the VCP test, subjects pointed to a remembered target following passive whole body rotation in the dark. In the first experiment, subjects performed VCP before and after wearing 0.5X minifying lenses that adaptively attenuate horizontal VOR gain. Results showed that adaptive reduction in horizontal VOR gain was accompanied by a commensurate change in VCP performance. In the second experiment, bilaterally labyrinthine deficient (LD) subjects were tested to confirm that vestibular cues were central to the spatial coding of both eye and hand movements during VCP. LD subjects performed significantly worse than normal subjects. These results demonstrate that adaptive change in VOR can lead to alterations in manual target localization.

Low intensity galvanic vestibulo-ocular reflex in normal subjects

1998 ◽  
Vol 28 (5) ◽  
pp. 413-422 ◽  
Author(s):  
G Quarck ◽  
O Etard ◽  
H Normand ◽  
M Pottier ◽  
P Denise
Keyword(s):  
Normal Subjects ◽  
Low Intensity ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex

Eye-head coordination in darkness: Formulation and testing of a mathematical model

2003 ◽  
Vol 13 (2-3) ◽  
pp. 79-91
Author(s):  
Stefano Ramat ◽  
Roberto Schmid ◽  
Daniela Zambarbieri
Keyword(s):  
Mathematical Model ◽  
Vestibular System ◽  
Sensory Information ◽  
Head Rotation ◽  
Normal Subjects ◽  
Head Movements ◽  
Vestibular Nystagmus ◽  
Ocular Reflex ◽  
Head Displacement ◽  
Vestibulo Ocular Reflex

Passive head rotation in darkness produces vestibular nystagmus, consisting of slow and quick phases. The vestibulo-ocular reflex produces the slow phases, in the compensatory direction, while the fast phases, in the same direction as head rotation, are of saccadic origin. We have investigated how the saccadic components of the ocular motor responses evoked by active head rotation in darkness are generated, assuming the only available sensory information is that provided by the vestibular system. We recorded the eye and head movements of nine normal subjects during active head rotation in darkness. Subjects were instructed to rotate their heads in a sinusoidal-like manner and to focus their attention on producing a smooth head rotation. We found that the desired eye position signal provided to the saccadic mechanism by the vestibular system may be modeled as a linear combination of head velocity and head displacement information. Here we present a mathematical model for the generation of both the slow and quick phases of vestibular nystagmus based on our findings. Simulations of this model accurately fit experimental data recorded from subjects.

Clinical Prevalence of Enhanced Vestibulo-Ocular Reflex Responses on Video Head Impulse Test

2021 ◽  
Vol Publish Ahead of Print ◽  
Author(s):  
Aitor Vargas-Alvarez ◽  
Elisabeth Ninchritz-Becerra ◽  
Miren Goiburu ◽  
Frank Betances ◽  
Jorge Rey-Martinez ◽  
...  
Keyword(s):  
Head Impulse Test ◽  
Video Head Impulse Test ◽  
Head Impulse ◽  
Reflex Responses ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex

The Electrically Evoked Vestibulo-Ocular Reflex: I. Normal Subjects

1991 ◽  
Vol 104 (2) ◽  
pp. 219-224 ◽  
Author(s):  
Dennis M. Moore ◽  
Larry F. Hoffman ◽  
Karl Beykirch ◽  
Vicente Honrubia ◽  
Robert W. Baloh
Keyword(s):  
Normal Subjects ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex

Visual-Vestibular Interaction with Telescopic Spectacles

1991 ◽  
Vol 1 (3) ◽  
pp. 263-277 ◽  
Author(s):  
J.L. Demer ◽  
J. Goldberg ◽  
F.I. Porter ◽  
H.A. Jenkins ◽  
K. Schmidt
Keyword(s):  
Eye Movements ◽  
Retinal Image ◽  
Head Rotation ◽  
Normal Subjects ◽  
Head Movements ◽  
Head Velocity ◽  
Ocular Reflex ◽  
Clear Vision ◽  
Visual Vestibular Interaction ◽  
Vestibulo Ocular Reflex

Vestibularly and visually driven eye movements interact to compensate for head movements to maintain the necessary retinal image stability for clear vision. The wearing of highly magnifying telescopic spectacles requires that such compensatory visual-vestibular interaction operate in a quantitative regime much more demanding than that normally encountered. We employed electro-oculography to investigate the effect of wearing of 2×, 4×, and 6× binocular telescopic spectacles on visual-vestibular interactions during sinusoidal head rotation in 43 normal subjects. All telescopic spectacle powers produced a large, immediate increase in the gain (eye velocity/head velocity) of compensatory eye movements, called the visual-vestibulo-ocular reflex (VVOR). However, the amount of VVOR gain augmentation became limited as spectacle magnification and the amplitude of head velocity increased. Optokinetic responses during wearing of telescopic spectacles exhibited a similar nonlinearity with respect to stimulus amplitude and spectacle magnification. Computer simulation was used to demonstrate that the nonlinear response of the VVOR with telescopic spectacles is a result of nonlinearities in visually guided tracking movements. Immediate augmentation of VVOR gain by telescopic spectacles declined significantly with increasing age in the subject pool studied. Presentation of unmagnified visual field peripheral to the telescopic spectacles reduced the immediate VVOR gain-enhancing effect of central magnified vision. These results imply that the VVOR may not be adequate to maintain retinal image stability during head movements when strongly magnifying telescopic spectacles are worn.

Sign in / Sign up

Export Citation Format

Share Document