Three-dimensional organization of vestibular-related eye movements to off-vertical axis rotation and linear translation in pigeons

1999 ◽  
Vol 129 (3) ◽  
pp. 0391-0400 ◽  
Author(s):  
J. David Dickman ◽  
Dora E. Angelaki
Keyword(s):  
Eye Movements ◽  
Three Dimensional ◽  
Vertical Axis ◽  
Axis Rotation

Three-Dimensional Computation during Off-Vertical Axis Rotation (OVAR) in Monkeys

2006 ◽  
Vol 65 (6) ◽  
pp. 429-439 ◽  
Author(s):  
Keisuke Kushiro ◽  
Jun Maruta
Keyword(s):  
Three Dimensional ◽  
Vertical Axis ◽  
Axis Rotation

Eye Movements and Motion Perception Induced by Off-vertical Axis Rotation (OVAR) at Small Angles of Tilt after Spaceflight

1995 ◽  
Vol 115 (5) ◽  
pp. 603-609 ◽  
Author(s):  
Gilles Clement ◽  
Christian Darlot ◽  
Anna Petropoulos ◽  
Alain Berthoz
Keyword(s):  
Eye Movements ◽  
Motion Perception ◽  
Vertical Axis ◽  
Axis Rotation

Functional and anatomic organization of three-dimensional eye movements in rabbit cerebellar flocculus

1994 ◽  
Vol 72 (1) ◽  
pp. 31-46 ◽  
Author(s):  
J. Van der Steen ◽  
J. I. Simpson ◽  
J. Tan
Keyword(s):  
Eye Movements ◽  
White Matter ◽  
Coordinate System ◽  
Three Dimensional ◽  
Vertical Axis ◽  
Short Latency ◽  
The Other ◽  
Response Component ◽  
Electrical Microstimulation ◽  
Cerebellar Flocculus

1. The three -dimensional, binocular eye movements evoked by electrical microstimulation of the cerebellar flocculus of alert, pigmented rabbits were recorded using the scleral search coil technique. The components of these eye movements were obtained in reference to an orthogonal coordinate system consisting of a vertical axis and two horizontal axes at 45 degrees and 135 degrees azimuth. The azimuth coordinate was taken to increase to both sides from the 0 degrees reference in the direction of the nose. 2. Eye movements were evoked most readily by stimulation (0.2 -ms pulses at 200 Hz for 1 s, intensity < or = 20 microA) at loci in the deep granular layer and the white matter. They consisted of slow (5–20 deg/s) movements. The responses were either binocular, with the eye ipsilateral to the stimulated flocculus usually having the larger amplitude, or were monocular, in which case they were restricted to the ipsilateral eye. 3. The evoked responses were classified according to the combination of the largest measured component of rotation for the two eyes and its sense of rotation (clockwise, CW, or counterclockwise, CCW). Seventy -eight percent of the evoked eye movements could be placed in one of two classes. For one of these classes the largest response component was a short -latency abduction of the ipsilateral eye about its vertical axis (19%), whereas for the other class (59%), the largest response component was a short -latency CCW rotation of the ipsilateral (left) eye about its 135 degrees axis. This response was frequently (50%) accompanied by a smaller short -latency CW rotation of the contralateral (right) eye about its 45 degrees axis. 4. The two main classes of three -dimensional eye movements are associated differentially with anatomically distinguishable compartments that are revealed by acetylcholinesterase histochemistry. Of the five anatomically distinguishable compartments in the floccular white matter, three are predominant. The middle of these three compartments is associated with the vertical axis class of movements, whereas the two adjacent compartments are associated with the 135 degrees class of eye movements. The eye movement relation of the other two, smaller compartments, was not determined. 5. The spatial orientation of the rotation axes of the two main classes of evoked eye movements closely corresponds to that of the preferred axes of the visual climbing fiber input to the flocculus. This suggests that both are organized in a similar coordinate system.(ABSTRACT TRUNCATED AT 400 WORDS)

Compensatory and Orienting Eye Movements Induced By Off-Vertical Axis Rotation (OVAR) in Monkeys

2002 ◽  
Vol 88 (5) ◽  
pp. 2445-2462 ◽  
Author(s):  
Keisuke Kushiro ◽  
Mingjia Dai ◽  
Mikhail Kunin ◽  
Sergei B. Yakushin ◽  
Bernard Cohen ◽  
...  
Keyword(s):  
Eye Movements ◽  
Vertical Axis ◽  
Velocity Storage ◽  
Eye Position ◽  
Rotational Axis ◽  
Vestibuloocular Reflex ◽  
Time Constants ◽  
Head Velocity ◽  
Axis Rotation ◽  
Eye Velocity

Nystagmus induced by off-vertical axis rotation (OVAR) about a head yaw axis is composed of a yaw bias velocity and modulations in eye position and velocity as the head changes orientation relative to gravity. The bias velocity is dependent on the tilt of the rotational axis relative to gravity and angular head velocity. For axis tilts <15°, bias velocities increased monotonically with increases in the magnitude of the projected gravity vector onto the horizontal plane of the head. For tilts of 15–90°, bias velocity was independent of tilt angle, increasing linearly as a function of head velocity with gains of 0.7–0.8, up to the saturation level of velocity storage. Asymmetries in OVAR bias velocity and asymmetries in the dominant time constant of the angular vestibuloocular reflex (aVOR) covaried and both were reduced by administration of baclofen, a GABAB agonist. Modulations in pitch and roll eye positions were in phase with nose-down and side-down head positions, respectively. Changes in roll eye position were produced mainly by slow movements, whereas vertical eye position changes were characterized by slow eye movements and saccades. Oscillations in vertical and roll eye velocities led their respective position changes by ≈90°, close to an ideal differentiation, suggesting that these modulations were due to activation of the orienting component of the linear vestibuloocular reflex (lVOR). The beating field of the horizontal nystagmus shifted the eyes 6.3°/ g toward gravity in side down position, similar to the deviations observed during static roll tilt (7.0°/ g). This demonstrates that the eyes also orient to gravity in yaw. Phases of horizontal eye velocity clustered ∼180° relative to the modulation in beating field and were not simply differentiations of changes in eye position. Contributions of orientating and compensatory components of the lVOR to the modulation of eye position and velocity were modeled using three components: a novel direct otolith-oculomotor orientation, orientation-based velocity modulation, and changes in velocity storage time constants with head position re gravity. Time constants were obtained from optokinetic after-nystagmus, a direct representation of velocity storage. When the orienting lVOR was combined with models of the compensatory lVOR and velocity estimator from sequential otolith activation to generate the bias component, the model accurately predicted eye position and velocity in three dimensions. These data support the postulates that OVAR generates compensatory eye velocity through activation of velocity storage and that oscillatory components arise predominantly through lVOR orientation mechanisms.

scholarly journals Sensory Basis and Functional Role of Eye Movements Elicited During Locomotion in the Land Crab Cardisoma Guanhumi

1990 ◽  
Vol 154 (1) ◽  
pp. 99-118 ◽  
Author(s):  
W. JON P. BARNES ◽  
P. Barnes
Keyword(s):  
Eye Movements ◽  
Flow Field ◽  
Body Movement ◽  
Three Dimensional ◽  
Vertical Axis ◽  
The Body ◽  
Image Motion ◽  
Optokinetic Responses ◽  
Land Crabs ◽  
Cardisoma Guanhumi

Eye movements in the horizontal plane and the rotatory component of body movement have been continuously recorded in land crabs, Cardisoma guanhumi Latreille, walking freely in an arena. The results show that the eyes compensate for locomotor turns by moving in the opposite direction to the body, thus reducing the image motion of surrounding objects on the retina. Gains often approach unity, so that stabilization of the rotatory component of self-generated image motion is good. Of the three compensatory eye reflexes that could contribute to these responses, optokinetic responses play a major role, since the gain of the responses of freely walking blinded crabs was about half that of crabs that could see. Since blinded crabs held above a ball moved their eyes whenever they rotated the ball about a vertical axis (i.e. turned), a significant role for leg proprioceptor-driven eye movements is also presumed. It is unclear whether vestibular nystagmus, driven by the statocysts, also has a role to play. In contrast to the high-gain compensatory responses that accompany turns, the translatory component of locomotion elicits compensatory eye movements only under the most favourable circumstances, when the crab walks along a runway facing a set of stripes. Even then, the responses are of very low gain (0.02-0.09). Amongst several possible factors, this is partly because lateral ommatidia, which drive the optokinetic responses, will face the poles of the flow field during sideways walking, and partly because stationary contrasts (as occur at the poles of the flow field) reduce the gain of optokinetic responses. It is argued that, by compensating for turns but not translatory locomotor movements, crabs effectively separate the rotatory from the translatory components of the visual flow field around them. Since only the former can be used in course control, while only the latter provides information on ground speed and the three-dimensional layout of the environment, such a separation makes good functional sense.

Off-Vertical Axis Rotation: A Test of the Otolith-Ocular Reflex

1992 ◽  
Vol 101 (8) ◽  
pp. 643-650 ◽  
Author(s):  
Joseph M. R. Furman ◽  
Robert H. Schor ◽  
Timothy L. Schumann
Keyword(s):  
Eye Movements ◽  
Semicircular Canal ◽  
Constant Velocity ◽  
Vertical Axis ◽  
Induced Response ◽  
Movement Response ◽  
Ocular Reflex ◽  
Vestibulo Ocular Reflex ◽  
Axis Rotation ◽  
Asymptomatic Subjects

The vestibulo-ocular reflex was studied via off-vertical axis rotation (OVAR) in the dark. The axis of the turntable could be tilted from vertical by up to 30°. Eye movements were measured with electro-oculography. Results from healthy asymptomatic subjects indicated that 1) a reliable otolith-induced response could be obtained during constant velocity OVAR using a velocity of 60°/s with a tilt of 30°; 2) constant velocity OVAR rotation was nausea-producing and, especially if subjects were rotated in the dark about an earth-vertical axis prior to being tilted, disorienting; and 3) sinusoidal OVAR produced minimal nausea; the eye movement response appeared to be the result of a combination of semicircular canal and otolith components. We conclude that OVAR has the potential of becoming a useful method for clinically assessing both the otolith-ocular reflex and semicircular canal—otolith interaction.

Eye movements induced by off-vertical axis rotation (OVAR) at small angles of tilt

1988 ◽  
Vol 73 (1) ◽  
pp. 91-105 ◽  
Author(s):  
C. Darlot ◽  
P. Denise ◽  
J. Droulez ◽  
B. Cohen ◽  
A. Berthoz
Keyword(s):  
Eye Movements ◽  
Vertical Axis ◽  
Axis Rotation
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