Visual-Vestibular Interaction in Humans During Active and Passive, Vertical Head Movement1

1993 ◽  
Vol 3 (2) ◽  
pp. 101-114
Author(s):  
Joseph L. Demer ◽  
John G. Oas ◽  
Robert W. Baloh
Keyword(s):  
Head Movement ◽  
Human Subjects ◽  
Single Frequency ◽  
Normal Vision ◽  
Frequency Range ◽  
Gain Enhancement ◽  
Ocular Reflex ◽  
Sinusoidal Motion ◽  
Visual Vestibular Interaction ◽  
Vestibulo Ocular Reflex

We studied visual-vestibular interaction (VVI) in 9 normal human subjects using active and passive vertical head rotations. Gain and phase of the vertical vestibulo-ocular reflex (VOR) and visually enhanced vestibulo-ocular reflex (VVOR) were measured for single frequency sinusoidal motion, as well as for sinusoidal motion of continuously increasing frequency, over the range of 0.4 to 4.0 Hz. In addition to measurement of VVOR during normal vision, telescopic spectacles having a magnification of 1.9× were used to challenge VVI to facilitate measurement of visual enhancement of VOR gain. In the mid-frequency range (1.6 to 2.4 Hz), the active VOR exhibited gain closer to compensatory than did the passive VOR; at other frequencies, active and passive VOR gains were similar. VVOR gain during normal vision was compensatory for both active and passive motion throughout the frequency range tested. VVOR gain with 1.9× telescopic spectacles was greater than VOR gain at all frequencies tested, including up to 3.2 Hz for passive bead movements, and up to 4.0 Hz for active head movement. However, gain enhancement with telescopic spectacles was consistently greater during active than during passive head movement. Phase errors for the VOR and VVOR were small under all testing conditions. Although active VOR and VVOR were directionally symmetrical, gain of upward slow phases differed from that of downward slow phases for passive VOR and VVOR in a manner depending on rotational frequency. For both active and passive testing, gain and phase values obtained during swept frequency rotations were similar to those obtained during single frequency sinusoidal testing. These data indicate that VVI can enhance gain of the passive vertical VOR even at frequencies above what is usually considered to be the upper limit of visual pursuit tracking. The additional enhancement observed during active bead movements at these high frequences is attributable to use of efference copy of the skeletal motor command to neck musculature.

Plasticity in the adult vestibulo-ocular reflex arc

1977 ◽  
Vol 278 (961) ◽  
pp. 319-334 ◽  
Keyword(s):  
Human Subjects ◽  
Neural Model ◽  
Reflex Response ◽  
Normal Vision ◽  
Ocular Reflex ◽  
Field Of Vision ◽  
Reflex Arc ◽  
Vestibulo Ocular Reflex ◽  
Plastic Changes

Human subjects with maintained reversal of their horizontal field of vision exhibit very substantial adaptive changes in their ‘horizontal’ vestibulo-ocular reflex (v.o.r.). Short durations (8 min) of vision reversal during natural head movement led to 20 % v.o.r. attenuation while long periods (4 weeks) eventually led to approximate reversal of the reflex. The reversed condition is approached by a complex, but highly systematic, series of changes in gain and phase of the reflex response relative to normal. Recovery after return to normal vision exhibits a similar duration, but different pattern, to that of the original adaptation. A chronic cat preparation with long-term optical reversal of vision has now been developed and shows similar adaptive and recovery changes at low test stimulus amplitudes, but different patterns of adaptive response at high amplitudes. An adaptive neural model employing mown vestibulo-ocular pathways is proposed to account for these experimentally observed plastic changes. The model is used to predict the adapted response to patterns of stimulation extending beyond the range of experimental investigation.

Predictive Mechanisms of Head-Eye Coordination and Vestibulo-Ocular Reflex Suppression in Humans

1992 ◽  
Vol 2 (3) ◽  
pp. 193-212 ◽  
Author(s):  
G.R. Barnes ◽  
M.A. Grealy
Keyword(s):  
Peak Velocity ◽  
Human Subjects ◽  
Head Movements ◽  
Whole Body ◽  
Head Velocity ◽  
The Gaze ◽  
Ocular Reflex ◽  
Sinusoidal Motion ◽  
Smooth Component ◽  
Vestibulo Ocular Reflex

Head and eye movements of human subjects have been recorded during head-free pursuit in the horizontal plane of a target executing sinusoidal motion at a frequency of 0.26 to 0.78 Hz and a peak velocity of ±96∘/s. The target was not presented continuously but was exposed for brief durations of 120 to 320 ms as it passed through the centre of the visual field at peak velocity. This technique allowed the timing of each response to be assessed in relation to the onset of target appearance. During the first 3 to 4 target presentations, there was a progressive buildup of both head velocity and the smooth component of gaze velocity, while, simultaneously, the responses became more phase-advanced with respect to target onset. In the steady state, similar temporal response trajectories were observed for head and gaze velocity, which were initiated approximately 500 ms prior to target on-set, rose to a peak that increased with the duration of target exposure, and then decayed with a time constant of 0.5 to 1 s. Whenever the target failed to appear as expected, the gaze and head velocity trajectories continued to be made, indicating that predictive suppression of the vestibulo-ocular reflex (VOR) was taking place in darkness. In a further experiment, subjects attempted to suppress the VOR during whole body oscillation at 0.2 or 0.4 Hz on a turntable by fixating, a head-fixed target that appeared for 10 to 160 ms at the time of peak head velocity. Again, VOR suppression was initiated prior to target appearance in the same manner as for natural head movements, and when the target suddenly disappeared but rotation continued, predictive VOR suppression was observed in darkness. The similarity of these predictive effects to those obtained previously for head-fixed pursuit provides further support for the hypothesis that both pursuit and visual suppression of the VOR are controlled primarily by identical visual feedback mechanisms.

Bilateral Vestibular Loss, Oscillopsia, and the Cervico-Ocular Reflex

1985 ◽  
Vol 93 (3) ◽  
pp. 403-407 ◽  
Author(s):  
Brian R. Chambers ◽  
Mabel Mai ◽  
Hugh O. Barber
Keyword(s):  
Frequency Band ◽  
Head Movement ◽  
Vestibular Loss ◽  
Ocular Reflex ◽  
Bilateral Vestibular Loss ◽  
Asymptomatic Patients ◽  
Visual Vestibular Interaction ◽  
Oculomotor Responses ◽  
Vestibulo Ocular Reflex ◽  
Normal Controls

Oscillopsia during head movement occurs in patients with bilateral vestibular loss and may be transient or persistent. To investigate mechanisms underlying recovery we tested the vestibulo-ocular reflex (VOR), visual-vestibular interaction, and the cervico-ocular reflex (COR); we used a pseudorandom oscillatory stimulus with a frequency band width of 0 to 5 Hz in six patients with bilaterally absent caloric responses and in 10 normal controls. Seven control subjects had low-gain COR responses, but these were anticompensatory with respect to the VOR. Three asymptomatic patients with an absent or grossly deficient VOR had increased oculomotor responses at all frequencies when oscillated in light. Compensatory COR responses were detected in these patients but not in patients with persisting oscillopsia. In some patients with bilateral vestibular loss, augmented cervico-ocular and visual reflexes may compensate, at least partially, for an absent VOR.

Frequency dependence of cat vestibulo-ocular reflex direction adaptation: Single frequency and multifrequency rotations

1991 ◽  
Vol 550 (1) ◽  
pp. 137-141 ◽  
Author(s):  
K.D. Powell ◽  
K.J. Quinn ◽  
S.A. Rude ◽  
B.W. Peterson ◽  
J.F. Baker
Keyword(s):  
Frequency Dependence ◽  
Single Frequency ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex

A vestibulo-ocular reflex with no head movement

1986 ◽  
Vol 55 (1) ◽  
pp. 1-4 ◽  
Author(s):  
M. G. Paulin ◽  
J. C. Montgomery
Keyword(s):  
Head Movement ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex

Comparison of Horizontal and Vertical Dynamic Visual Acuity in Patients with Vestibular Dysfunction and Nonvestibular Dizziness

2007 ◽  
Vol 18 (03) ◽  
pp. 236-244 ◽  
Author(s):  
Richard A. Roberts ◽  
Richard E. Gans
Keyword(s):  
Visual Acuity ◽  
Head Movement ◽  
Vestibular Function ◽  
Vestibular Dysfunction ◽  
Common Symptom ◽  
Dynamic Visual Acuity ◽  
Blurred Vision ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex ◽  
Horizontal Head

Blurred vision with head movement is a common symptom reported by patients with vestibular dysfunction affecting the vestibulo-ocular reflex (VOR). Impaired VOR can be measured by comparing visual acuity in which there is no head movement to visual acuity obtained with head movement. A previous study demonstrated that dynamic visual acuity (DVA) testing using vertical head movement revealed deficits in impaired VOR. There is evidence that horizontal head movement is more sensitive to impaired VOR. The objective of this investigation was to compare horizontal and vertical DVA in participants with normal vestibular function (NVF), impaired vestibular function (IVF), and participants with nonvestibular dizziness (NVD). Participants performed the visual acuity task in a baseline condition with no movement and also in two dynamic conditions, horizontal head movement and vertical head movement. Horizontal DVA was twice as sensitive to impaired VOR than vertical DVA. Results suggest that horizontal volitional head movement should be incorporated into tasks measuring functional deficits of impaired VOR. Una visión borrosa con los movimientos de la cabeza es un síntoma común reportado por los pacientes con una disfunción vestibular que afecta el reflejo vestíbulo-ocular (VOR). La alteración en el VOR puede ser medida comparando la aguda visual no acompañada de movimientos de la cabeza, con la aguda visual obtenida con movimientos cefálicos. Un estudio previo demostró que la prueba de aguda visual dinámica (DVA) usando movimiento vertical de la cabeza revelaba deficiencias relacionados con un VOR alterado. Existe evidencia que el movimiento cefálico horizontal es más sensible a un VOR alterado. El objetivo de esta investigación fue comparar el DVA horizontal y vertical en participantes con funcional vestibular normal (NVF), con función vestibular alterada (IVF) y en sujetos con mareo no vestibular (NVD). Los participantes realizaron sus tareas de agudeza visual en una condición basal, sin movimiento, y también en dos condiciones dinámicas, con movimientos de cabeza horizontales y verticales. El DVA horizontal fue dos veces más sensible a un VOR alterado que el DVA vertical. Los resultados sugieren que los movimientos volitivos horizontales de la cabeza deben incorporarse en las tareas que midan deficiencias funcionales con un VOR alterado.

scholarly journals Age-Related Changes in Human Vestibulo-Ocular Reflexes: Sinusoidal Rotation and Caloric Tests

1990 ◽  
Vol 1 (1) ◽  
pp. 49-59 ◽  
Author(s):  
R.J. Peterka ◽  
F.O. Black ◽  
M.B. Schoenhoff
Keyword(s):  
Human Subjects ◽  
Normal Population ◽  
Poor Correlation ◽  
Caloric Test ◽  
Compensatory Response ◽  
Ocular Reflex ◽  
Age Related ◽  
Test Parameters ◽  
Vestibulo Ocular Reflex ◽  
Effects Of Aging

The dynamic response properties of horizontal vestibulo-ocular reflex (VOR) were characterized in 216 human subjects ranging in age from 7 to 81 y. The effects of aging on VOR dynamics and parameter distributions that describe VOR responses to caloric and to sinusoidal rotational stimuli were determined in a putatively normal population. Caloric test parameters showed no consistent trend with age. Rotation test parameters showed declining response amplitude and slightly less compensatory response phase with increasing age. The magnitudes of these changes were not large relative to the variability within the population. The age-related trends in VOR were not consistent with the anatomic changes in the periphery reported by others that showed an increasing rate of peripheral hair cell and nerve fiber loss in subjects over 55 y. The poor correlation between physiological and anatomical data suggest that adaptive mechanisms in the central nervous system are important in maintaining the VOR.

Mechanisms of human vertical visual-vestibular interaction

1992 ◽  
Vol 68 (6) ◽  
pp. 2128-2146 ◽  
Author(s):  
J. L. Demer
Keyword(s):  
Head Rotation ◽  
Whole Body ◽  
Single Frequency ◽  
Head Motion ◽  
Visual Environment ◽  
Human Beings ◽  
Stimulus Motion ◽  
Stimulus Velocity ◽  
Gain Enhancement ◽  
Visual Vestibular Interaction

1. The purpose of this study was to infer the properties of the mechanisms contributing to visual-vestibular interaction (VVI) of human beings during vertical motion. Predictable trains of single-frequency sinusoids; poorly predictable sums of sinusoidal harmonics; and unpredictable random impulses of passive, whole-body rotation about a horizontal, interaural axis were produced by the use of a servo-driven chair at frequencies from 0.4 to 3.2 Hz. The vestibuloocular reflex (VOR) was studied in darkness with the use of the magnetic search coil technique to record eye movements during head rotation. Telescopic spectacles of varying magnifications and visual field areas were used as a challenging stimulus to induce substantial gain enhancement by VVI. Real and imagined targets moving with the head were used to induce gain reduction. VVI was compared with vertical smooth pursuit and small field optokinetic nystagmus (OKN) for similar stimulus motion. 2. The vertical VOR and visually enhanced VOR (VVOR) were directionally symmetrical. Viewing with telescopic spectacles of powers from x1.9-4 was associated with significantly increased gain at frequencies up to 2.0 Hz as compared with the VOR (P < 0.01). Gain enhancement was not strongly influenced by stimulus velocity for either predictable or poorly predictable head motion, and there was a trend toward greater VVOR gain at higher head velocities. Phase was compensatory at all frequencies for predictable sinusoids. For poorly predictable and unpredictable head motion, gain enhancement with telescopic spectacles was significantly less than during predictable head motion. During poorly predictable head motion, phase lags were observed that increased with frequency and telescopic spectacle power. 3. The perseverance of VVI during disappearance of the visual environment was evaluated by blanking it during various proportions of the cycle of predictable head rotation at frequencies from 0.8 to 2.4 Hz. Below 2.0 Hz, a trend toward gain enhancement was observed with x1.9 telescopic spectacles when the visual environment was present for as little as 6% of the sinusoidal cycle. This effect was statistically significant (P < 0.01) at 0.8 and 1.2 Hz when the visual environment was present for 50% of the cycle. 4. Suppression of the VOR was evaluated for visual fixation of real and imaginary head-fixed targets during predictable, poorly predictable, and unpredictable rotations. Fixation of a real target was most effective at low frequencies of predictable rotation and was significantly effective in reducing gain relative to the VOR at frequencies of < or = 2.4 Hz.(ABSTRACT TRUNCATED AT 400 WORDS)

Effects of body orientation and rotation axis on pitch visual-vestibular interaction

1999 ◽  
Vol 9 (1) ◽  
pp. 1-11
Author(s):  
Gilles Clément ◽  
Scott J. Wood ◽  
Corinna E. Lathan ◽  
Robert J. Peterka ◽  
Millard F. Reschke
Keyword(s):  
Rotation Axis ◽  
Human Subjects ◽  
Head Position ◽  
The Body ◽  
Body Orientation ◽  
Slow Phase ◽  
Eccentric Rotation ◽  
Rotation Axes ◽  
Visual Vestibular Interaction ◽  
Vestibulo Ocular Reflex

Spatial transformations of the vestibular-optokinetic system must account for changes in head position with respect to gravity in order to produce compensatory oculomotor responses. The purpose of this experiment was to study the influence of gravity on the vestibulo-ocular reflex (VOR) in darkness and on visual-vestibular interaction in the pitch plane in human subjects using two different comparisons: (1) Earth-horizontal axis (EHA) rotation about an upright versus a supine body orientation, and (2) Earth-horizontal versus Earth-vertical (EVA) rotation axes. Visual-vestibular responses (VVR) were evaluated by measuring the slow phase velocity of nystagmus induced during sinusoidal motion of the body in the pitch plane (at 0.2 Hz and 0.8 Hz) combined with a constant-velocity vertical optokinetic stimulation (at ±36°/s). The results showed no significant effect on the gain or phase of the VOR in darkness or on the VVR responses at 0.8 Hz between EHA upright and EHA supine body orientations. However, there was a downward shift in the VOR bias in darkness in the supine orientation. There were systematic changes in VOR and VVR between EHA and EVA for 0.2 Hz, including a reduced modulation gain, increased phase lead, and decreased bias during EVA rotation. The same trend was also observed at 0.8 Hz, but at a lesser extent, presumably due to the effects of eccentric rotation in our EVA condition and/or to the different canal input across frequencies. The change in the bias at 0.2 Hz between rotation in darkness and rotation with an optokinetic stimulus was greater than the optokinetic responses without rotation. During EHA, changes in head position relative to gravity preserve graviceptor input to the VVR regardless of body orientation. However, the modifications in VVR gain and phase when the rotation axis is aligned with gravity indicate that this graviceptive information is important for providing compensatory eye movements during visual-vestibular interaction in the pitch plane.

Measurement of the vestibulo-ocular reflex by magnetometry during active head movement

1996 ◽  
Vol 30 (5) ◽  
pp. 325-331
Author(s):  
Christopher P. Aldren ◽  
John E. Fitzgerald ◽  
Peter Kelly ◽  
John P. Birchall ◽  
Alan Murray
Keyword(s):  
Head Movement ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex
Sign in / Sign up

Export Citation Format

Share Document