The human horizontal vestibulo-ocular reflex in response to high-acceleration stimulation before and after unilateral vestibular neurectomy

1990 ◽  
Vol 81 (3) ◽  
pp. 479-490 ◽  
Author(s):  
G. M. Halmagyi ◽  
I. S. Curthoys ◽  
P. D. Cremer ◽  
C. J. Henderson ◽  
M. J. Todd ◽  
...  
Keyword(s):  
Vestibular Neurectomy ◽  
Ocular Reflex ◽  
High Acceleration ◽  
Before And After ◽  
Vestibulo Ocular Reflex ◽  
Unilateral Vestibular Neurectomy

Unilateral Vestibular Neurectomy in Man Causes a Severe Permanent Horizontal Vestibulo-ocular Reflex Deficit in Response to High-acceleration Ampullofugal Stimulation

1991 ◽  
Vol 111 (sup481) ◽  
pp. 411-414 ◽  
Author(s):  
G. M. Halmagyi ◽  
I. S. Curthoys ◽  
M. J. Todd ◽  
D. M. D'cruz ◽  
P. D. Cremer ◽  
...  
Keyword(s):  
Vestibular Neurectomy ◽  
Ocular Reflex ◽  
High Acceleration ◽  
Vestibulo Ocular Reflex ◽  
Unilateral Vestibular Neurectomy

Effect of Incisions in the Brainstem Commissural Network on the Short-Term Vestibulo-Ocular Adaptation of the CAT

1991 ◽  
Vol 1 (3) ◽  
pp. 223-239
Author(s):  
G. Cheron
Keyword(s):  
Low Frequency ◽  
Adaptive Plasticity ◽  
Training Procedure ◽  
Optokinetic Response ◽  
Mean Values ◽  
Ocular Reflex ◽  
Optokinetic Reflex ◽  
Before And After ◽  
Vestibulo Ocular Reflex ◽  
Vor Adaptation

This study was intended to test the adaptive plasticity of the vestibulo-ocular reflex before and after either a midsagittal or parasagittal incision in the brainstem. Eye movements were measured with the electromagnetic search coil technique during the vestibulo-ocular reflex (VORD) in the dark, the optokinetic reflex (OKN), and the visuo-vestibular adaptive training procedure. Two types of visual-vestibular combined stimulation were applied by means of low frequency stimuli (0.05 to 0.10 Hz). In order to increase or decrease the VORD gain, the optokinetic drum was oscillated either 180∘ out-of-phase or in-phase with the vestibular stimulus turntable. This “training” procedure was applied for 4 hours. Initial measurements of the VORD were normal with a mean gain value of 0.92 ± 0.08. After 4 hours of “training” with the out-of-phase condition (180∘), VORD gain reached mean values of 1.33 ± 0.11 (n = 6 cats). In the in-phase combination, the mean VORD gain decreased from 1.0 to 0.63 ± 0.02 (n = 2 cats). No significant change of VORD phase was found in any of the cats. Midsagittal or parasagittal pontomedullary brainstem incisions were performed in 4 cats. Recovery of the VOR was tested on the 2nd, 7th, and 30th day after operation. After the 30th day, recovery of the VORD gain stabilized at about 66% of the initial preoperative value. At this stage of the recovery, the optokinetic response (OKN) of the midsagittal-Iesioned cats was practically normal: in the parasagittal-Jesioned cats, the postoperative OKN responses were asymmetric. After stabilization of recovery, lesioned cats were trained with the same adaptation procedure. Although the direct effect of the visuo-vestibular combined stimulation during the training was still operative in all lesioned cats, the adaptive plasticity was completely abolished by the lesions. These results suggest that the commissural brainstem network may play a crucial role in the acquisition of the forced VOR adaptation.

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.

The three-dimensional vestibulo-ocular reflex evoked by high-acceleration rotations in the squirrel monkey

2004 ◽  
Vol 159 (4) ◽  
pp. 433-446 ◽  
Author(s):  
Americo A. Migliaccio ◽  
Michael C. Schubert ◽  
Patpong Jiradejvong ◽  
David M. Lasker ◽  
Richard A. Clendaniel ◽  
...  
Keyword(s):  
Squirrel Monkey ◽  
Three Dimensional ◽  
Ocular Reflex ◽  
High Acceleration ◽  
Vestibulo Ocular Reflex

Occupation and Visual/Vestibular Interaction in Vestibular Rehabilitation

1995 ◽  
Vol 112 (4) ◽  
pp. 526-532 ◽  
Author(s):  
Helen Cohen ◽  
Maureen Kane-Wineland ◽  
Laura V. Miller ◽  
Catherine L. Hatfield
Keyword(s):  
Motor Skills ◽  
Therapy Group ◽  
Exercise Program ◽  
Head Movements ◽  
Vestibular Disorders ◽  
Essential Factor ◽  
Gross Motor Skills ◽  
Ocular Reflex ◽  
Before And After ◽  
Vestibulo Ocular Reflex

Otolaryngologists often prescribe head movement exercise programs for patients with vestibular disorders, although the effectiveness of these programs and the critical features of the exercises are poorly understood. Because many patients who dislike exercising do not follow through with their exercises, alternatives to the traditional repetitive exercises would be useful. Subjects diagnosed with vestibular disorders were treated for 6 weeks with either an outpatient exercise program that incorporated interesting, purposeful activities or a simple home program of head movements, comparable with the exercises otolaryngologists often give their patients when they do not refer to rehabilitation. Both treatments incorporated repetitive head movements in all planes in space, graduated in size and speed. Subjects were all tested before and after treatment with standard measures of vestibulo-ocular reflex and balance, level of vertigo, gross motor skills, and self-care independence. Subjects in both groups improved significantly on the functional measures, with slightly greater improvements in the occupational therapy group. The results were maintained 3 months after the cessation of intervention. These data suggest that graded purposeful activities are a useful alternative for treating this patient population and that the essential factor in any exercise program is the use of repetitive head movements.

Vestibular adaptation to centrifugation does not transfer across planes of head rotation

2008 ◽  
Vol 18 (1) ◽  
pp. 25-37
Author(s):  
Ian Garrick-Bethell ◽  
Thomas Jarchow ◽  
Heiko Hecht ◽  
Laurence R. Young
Keyword(s):  
Sagittal Plane ◽  
Head Rotation ◽  
Head Movements ◽  
Control Group ◽  
Illusory Motion ◽  
Ocular Reflex ◽  
Before And After ◽  
Out Of Plane ◽  
Vestibulo Ocular Reflex ◽  
Axis Rotation

Out-of-plane head movements performed during fast rotation produce non-compensatory nystagmus, sensations of illusory motion, and often motion sickness. Adaptation to this cross-coupled Coriolis stimulus has previously been demonstrated for head turns made in the yaw (transverse) plane of motion, during supine head-on-axis rotation. An open question, however, is if adaptation to head movements in one plane of motion transfers to head movements performed in a new, unpracticed plane of motion. Evidence of transfer would imply the brain builds up a generalized model of the vestibular sensory-motor system, instead of learning a variety of individual input/output relations separately. To investigate, over two days 9 subjects performed pitch head turns (sagittal plane) while rotating, before and after a series of yaw head turns while rotating. A Control Group of 10 subjects performed only the pitch movements. The vestibulo-ocular reflex (VOR) and sensations of illusory motion were recorded in the dark for all movements. Upon comparing the two groups we failed to find any evidence of transfer from the yaw plane to the pitch plane, suggesting that adaptation to cross-coupled stimuli is specific to the particular plane of head movement. The findings have applications for the use of centrifugation as a possible countermeasure for long duration spaceflight. Adapting astronauts to unconstrained head movements while rotating will likely require exposure to head movements in all planes and directions.

Dynamics of Adaptive Change in Human Vestibulo-Ocular Reflex Direction

1990 ◽  
Vol 1 (1) ◽  
pp. 23-29
Author(s):  
T.T. Khater ◽  
J.F. Baker ◽  
B.W. Peterson
Keyword(s):  
Eye Movements ◽  
Vertical Component ◽  
Onset Time ◽  
Eye Position ◽  
Complete Darkness ◽  
Ocular Reflex ◽  
Before And After ◽  
Adaptation Procedure ◽  
Vestibulo Ocular Reflex ◽  
Horizontal Rotations

Adaptive modification of vestibulo-ocular reflex (VOR) direction was characterized in humans by recording vertical and horizontal VOR eye movements during horizontal rotations in darkness at frequencies of 0.05 to 1 Hz before and after exposure to a VOR direction adaptation procedure. This procedure paired yaw horizontal vestibular rotation at 0.25 Hz with synchronous pitch vertical optokinetic motion. Saccades were removed from eye position records and VOR gain and phase were recorded. With an onset time constant of 36 min, the VOR measured during horizontal rotation in complete darkness acquired a vertical component in phase with the optokinetic stimulus presented during adaptation. The amplitude of this newly acquired vertical VOR component was maximal during rotation at the frequency of adaptation; at other frequencies, the amplitude was lower, but still significant. Unlike VOR direction adaptation in cats, the phase of the adaptive VOR component in humans did not show significant leads or lags at test frequencies below or above the adaptation frequency. These data suggest that, like the cat, the human VOR can be directionally adapted, and the pathways involving the adaptive component of the VOR are frequency specific.

The Human Vertical Vestibuloocular Reflex in Response to High-Acceleration Stimulation after Unilateral Vestibular Neurectomy

1992 ◽  
Vol 656 (1 Sensing and C) ◽  
pp. 732-738 ◽  
Author(s):  
G. M. HALMAGYI ◽  
S. T. AW ◽  
P. D. CREMER ◽  
M. J. TODD ◽  
I. S. CURTHOYS
Keyword(s):  
Vestibuloocular Reflex ◽  
Vestibular Neurectomy ◽  
High Acceleration ◽  
Unilateral Vestibular Neurectomy

scholarly journals Vestibular neuritis: Vertigo and the high-acceleration vestibulo-ocular reflex

2008 ◽  
Vol 255 (10) ◽  
pp. 1479-1482 ◽  
Author(s):  
A. Palla ◽  
D. Straumann ◽  
A. M. Bronstein
Keyword(s):  
Vestibular Neuritis ◽  
Ocular Reflex ◽  
High Acceleration ◽  
Vestibulo Ocular Reflex

Contralesional High-Acceleration Vestibulo-Ocular Reflex Function in Vestibular Schwannoma

2021 ◽  
Vol Publish Ahead of Print ◽  
Author(s):  
Jennifer Wing Yee Lee ◽  
Fatemeh Hassannia ◽  
John Alexander Rutka
Keyword(s):  
Vestibular Schwannoma ◽  
Ocular Reflex ◽  
High Acceleration ◽  
Vestibulo Ocular Reflex
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