Sinusoidal Optokinetic Stimulation

ORL ◽  
1973 ◽  
Vol 35 (3-4) ◽  
pp. 171-177 ◽  
Author(s):  
L.B.W. Jongkees ◽  
W.J. Oosterveld
Keyword(s):  
Optokinetic Stimulation ◽  
Sinusoidal Optokinetic Stimulation

Cerebellar Nodulectomy Impairs Spatial Memory of Vestibular and Optokinetic Stimulation in Rabbits

2002 ◽  
Vol 87 (2) ◽  
pp. 962-975 ◽  
Author(s):  
N. H. Barmack ◽  
P. Errico ◽  
A. Ferraresi ◽  
H. Fushiki ◽  
V. E. Pettorossi ◽  
...  
Keyword(s):  
Pitch Angle ◽  
Time Course ◽  
Vestibular Stimulation ◽  
Slow Phase ◽  
Optokinetic Stimulation ◽  
Movement Velocity ◽  
Vertical Drift ◽  
Before And After ◽  
Sinusoidal Optokinetic Stimulation

Natural vestibular and optokinetic stimulation were used to investigate the possible role of the cerebellar nodulus in the regulation and modification of reflexive eye movements in rabbits. The nodulus and folium 9d of the uvula were destroyed by surgical aspiration. Before and after nodulectomy the vertical and horizontal vestibuloocular reflexes (VVOR, HVOR) were measured during sinusoidal vestibular stimulation about the longitudinal (roll) and vertical (yaw) axes. Although the gain of the HVOR (GHVOR = peak eye movement velocity/peak head velocity) was not affected by the nodulectomy, the gain of the VVOR (GVVOR) was reduced. The gains of the vertical and horizontal optokinetic reflexes (GVOKR, GHOKR) were measured during monocular, sinusoidal optokinetic stimulation (OKS) about the longitudinal and vertical axes. Following nodulectomy, there was no reduction in GVOKR or GHOKR. Long-term binocular OKS was used to generate optokinetic afternystagmus, OKAN II, that lasts for hours. After OKAN II was induced, rabbits were subjected to static pitch and roll, to determine how the plane and velocity of OKAN II is influenced by a changing vestibular environment. During static pitch, OKAN II slow phase remained aligned with earth-horizontal. This was true for normal and nodulectomized rabbits. During static roll, OKAN II remained aligned with earth-horizontal in normal rabbits. During static roll in nodulectomized rabbits, OKAN II slow phase developed a centripetal vertical drift. We examined the suppression and recovery of GVVOR following exposure to conflicting vertical OKS for 10–30 min. This vestibular-optokinetic conflict reduced GVVOR in both normal and nodulectomized rabbits. The time course of recovery of GVVOR after conflicting OKS was the same before and after nodulectomy. In normal rabbits, the head pitch angle, at which peak OKAN II velocity occurred, corresponded to the head pitch angle maintained during long-term OKS. If the head was maintained in a “pitched-up” or “pitched-down” orientation during long-term OKS, the subsequently measured OKAN II peak velocity occurred at the same orientation. This was not true for nodulectomized rabbits, who had OKAN II peak velocities at head pitch angles independent of those maintained during long-term OKS. We conclude that the nodulus participates in the regulation of compensatory reflexive movements. The nodulus also influences “remembered” head position in space derived from previous optokinetic and vestibular stimulation.

scholarly journals Motion Sickness and Migraine: Optokinetic Stimulation Increases Scalp Tenderness, Pain Sensitivity in the Fingers and Photophobia

Cephalalgia ◽  
2002 ◽  
Vol 22 (2) ◽  
pp. 117-124 ◽  
Author(s):  
PD Drummond
Keyword(s):  
Motion Sickness ◽  
Pain Sensitivity ◽  
Pain Perception ◽  
Optokinetic Stimulation ◽  
Nociceptive Pathways ◽  
General Influence

The aim of this study was to determine whether scalp tenderness and photophobia, two well-recognized symptoms of migraine, develop during the motion sickness induced by optokinetic stimulation. To investigate whether motion sickness has a general influence on pain perception, pain was also assessed in the fingertips. After optokinetic stimulation, nausea increased more and headache persisted longer in 21 migraine sufferers than in 15 non-headache controls. Scalp tenderness increased during optokinetic stimulation in nauseated subjects, and pain in the fingertips increased more and photophobia persisted longer in migraine sufferers than controls. These findings suggest that the disturbance responsible for nausea also sensitizes trigeminal nociceptive neurones or releases inhibitory controls on their discharge. A low nausea threshold and a propensity for sensitization to develop rapidly in nociceptive pathways may increase susceptibility to migraine.

Modification of Parameters in Vertical Optokinetic Nystagmus after Repeated Vertical Optokinetic Stimulation in Patients with Vestibular Lesions

1995 ◽  
Vol 115 (sup520) ◽  
pp. 419-422 ◽  
Author(s):  
Toshihiro Tsuzuku ◽  
Elisabeth Vitte ◽  
Alain Sémont ◽  
Alain Berthoz
Keyword(s):  
Optokinetic Nystagmus ◽  
Optokinetic Stimulation

Neural Processing of Gravito-Inertial Cues in Humans. IV. Influence of Visual Rotational Cues During Roll Optokinetic Stimuli

2003 ◽  
Vol 89 (1) ◽  
pp. 390-400 ◽  
Author(s):  
L. H. Zupan ◽  
D. M. Merfeld
Keyword(s):  
Visual Cues ◽  
Gravitational Force ◽  
Sensory Information ◽  
Inertial Force ◽  
Linear Acceleration ◽  
Otolith Organs ◽  
Optokinetic Stimulation ◽  
The Difference ◽  
The Right ◽  
Roll Tilt

Sensory systems often provide ambiguous information. For example, otolith organs measure gravito-inertial force (GIF), the sum of gravitational force and inertial force due to linear acceleration. However, according to Einstein's equivalence principle, a change in gravitational force due to tilt is indistinguishable from a change in inertial force due to translation. Therefore the central nervous system (CNS) must use other sensory cues to distinguish tilt from translation. For example, the CNS might use dynamic visual cues indicating rotation to help determine the orientation of gravity (tilt). This, in turn, might influence the neural processes that estimate linear acceleration, since the CNS might estimate gravity and linear acceleration such that the difference between these estimates matches the measured GIF. Depending on specific sensory information inflow, inaccurate estimates of gravity and linear acceleration can occur. Specifically, we predict that illusory tilt caused by roll optokinetic cues should lead to a horizontal vestibuloocular reflex compensatory for an interaural estimate of linear acceleration, even in the absence of actual linear acceleration. To investigate these predictions, we measured eye movements binocularly using infrared video methods in 17 subjects during and after optokinetic stimulation about the subject's nasooccipital (roll) axis (60°/s, clockwise or counterclockwise). The optokinetic stimulation was applied for 60 s followed by 30 s in darkness. We simultaneously measured subjective roll tilt using a somatosensory bar. Each subject was tested in three different orientations: upright, pitched forward 10°, and pitched backward 10°. Five subjects reported significant subjective roll tilt (>10°) in directions consistent with the direction of the optokinetic stimulation. In addition to torsional optokinetic nystagmus and afternystagmus, we measured a horizontal nystagmus to the right during and following clockwise (CW) stimulation and to the left during and following counterclockwise (CCW) stimulation. These measurements match predictions that subjective tilt in the absence of real tilt should induce a nonzero estimate of interaural linear acceleration and, therefore, a horizontal eye response. Furthermore, as predicted, the horizontal response in the dark was larger for Tilters ( n = 5) than for Non-Tilters ( n= 12).

Asymmetric Optokinetic Afterresponse in Patients with Small Acoustic Neurinomas1

1991 ◽  
Vol 1 (3) ◽  
pp. 299-307
Author(s):  
Krister Brantberg ◽  
Måns Magnusson
Keyword(s):  
Vestibular Function ◽  
Directional Asymmetry ◽  
Optokinetic Stimulation ◽  
Optokinetic Afternystagmus ◽  
Acoustic Neurinomas ◽  
Normal Controls

Directional asymmetry of primary and secondary optokinetic afternystagmus (OKAN I and OKAN II, respectively) was studied in 20 patients with small acoustic neurinomas (⩽20 mm), and results were compared to those for 24 normal controls. The optokinetic afterresponse was induced by 60 s of horizontal whole-field optokinetic stimulation in both directions. Among patients, the optokinetic afterresponse was asymmetric, OKAN I and OKAN II beating toward the lesioned ear being significantly weaker than the OKAN I and OKAN II beating toward the healthy ear. Hence, in these patients with gradual deterioration of vestibular function, the vestibular side-difference was reflected both in OKAN I and OKAN II. Although asymmetry in OKAN I was frequently observed among controls, it was significantly more pronounced among the patients. Moreover, patients could be distinguished by the occurrence of OKAN II, as it did not occur at all among controls exposed to the same stimulation.

Perception of Self-Motion From Peripheral Optokinetic Stimulation Suppresses Visual Evoked Responses to Central Stimuli

2003 ◽  
Vol 90 (2) ◽  
pp. 723-730 ◽  
Author(s):  
Kai V. Thilo ◽  
Andreas Kleinschmidt ◽  
Michael A. Gresty
Keyword(s):  
Optical Flow ◽  
Functional Neuroimaging ◽  
Stimulus Change ◽  
Object Motion ◽  
Large Field ◽  
Peripheral Stimulus ◽  
Optokinetic Stimulation ◽  
Central Visual Field ◽  
Self Motion ◽  
Visual Evoked

In a previous functional neuroimaging study we found that early visual areas deactivated when a rotating optical flow stimulus elicited the illusion of self-motion (vection) compared with when it was perceived as a moving object. Here, we investigated whether electrical cortical responses to an independent central visual probe stimulus change as a function of whether optical flow stimulation in the periphery induces the illusion of self-motion or not. Visual-evoked potentials (VEPs) were obtained in response to pattern-reversals in the central visual field in the presence of a constant peripheral large-field optokinetic stimulus that rotated around the naso-occipital axis and induced intermittent sensations of vection. As control, VEPs were also recorded during a stationary peripheral stimulus and showed no difference than those obtained during optokinetic stimulation. The VEPs during constant peripheral stimulation were then divided into two groups according to the time spans where the subjects reported object- or self-motion, respectively. The N70 VEP component showed a significant amplitude reduction when, due to the peripheral stimulus, subjects experienced self-motion compared to when the peripheral stimulus was perceived as object-motion. This finding supplements and corroborates our recent evidence from functional neuroimaging that early visual cortex deactivates when a visual flow stimulus elicits the illusion of self-motion compared with when the same sensory input is interpreted as object-motion. This dampened responsiveness might reflect a redistribution of sensorial and attentional resources when the monitoring of self-motion relies on a sustained and veridical processing of optic flow and may be compromised by other sources of visual input.

Optokinetic Stimulation Affects Both Vertical and Horizontal Deficits of Position Sense in Unilateral Neglect

Cortex ◽  
1995 ◽  
Vol 31 (4) ◽  
pp. 669-683 ◽  
Author(s):  
Giuseppe Vallar ◽  
Cecilia Guariglia ◽  
Luisa Magnotti ◽  
Luigi Pizzamiglio
Keyword(s):  
Position Sense ◽  
Optokinetic Stimulation ◽  
Unilateral Neglect
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