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Julio Rama-López, Francisco Guillén-Grima, Nicolás Pérez
OBJECTIVE: [corrected] To describe the results obtained for circularvection times (tCV) in a study of the phenomenon of visual-vestibular interaction for a population with vestibular pathology and to analyze differences in its calculation among patients reporting a worsening of their symptoms with visual stimuli. MATERIAL AND METHODS: A detailed case history was taken for all patients, followed by a sensory organization test using computerized dynamic posturography and the calculation of their tCV...
February 2007: Acta Otorrinolaringológica Española
Jeffrey R Basford, Li-Shan Chou, Kenton R Kaufman, Robert H Brey, Ann Walker, James F Malec, Anne M Moessner, Allen W Brown
OBJECTIVE: To assess the sensations of instability that many patients report after traumatic brain injury (TBI). DESIGN: A controlled study. SETTING: A motion analysis and vestibular and balance laboratory. PARTICIPANTS: Twenty subjects, 10 with TBI and complaints of instability, and 10 without TBI. INTERVENTIONS: Balance and gait analysis. MAIN OUTCOME MEASURES: Dizziness Handicap Inventory (DHI), caloric irrigation, optokinetic testing, Dix-Hallpike Test, posturography, and center of mass (COM) movement...
March 2003: Archives of Physical Medicine and Rehabilitation
Jaimee King, Calvin Young, John Highton, Paul F Smith, Cynthia L Darlington
The present study investigated vestibulo-ocular reflex (VOR), optokinetic reflex (OKR) and postural function in patients with rheumatoid arthritis (RA). Compared with controls, no differences in gaze-holding, VOR gain or phase, OKR slow phase velocity (SPV) or quick phase amplitude, optokinetic afternystagmus SPV or duration, or latency to the illusion of circularvection, were found. RA patients did exhibit greater sway in the leftward direction (P<0.01), however, this was no greater in the conditions of the Clinical Test of Sensory Interaction and Balance that increase reliance upon vestibular information...
August 9, 2002: Neuroscience Letters
Martha Nicholson, Jaimee King, Paul F Smith, Cynthia L Darlington
We compared vestibulo-ocular reflex, optokinetic reflex and postural function in subjects with insulin-dependent diabetes mellitus (IDDM) and non-insulin-dependent diabetes mellitus (NIDDM), as well as non-diabetic controls. Both IDDM and NIDDM subjects exhibited significant deficits in gaze-holding in darkness (p < 0.05), small changes in vestibulo-ocular reflex (VOR) phase re velocity (p < 0.005) without a change in VOR gain, and a decrease in optokinetic reflex (OKR) slow phase velocity (p < 0.001)...
January 21, 2002: Neuroreport
C L Darlington, A Ross, J King, P F Smith
We investigated the effects of the menstrual cycle on visual-vestibular interaction by measuring optokinetic function and postural stability at different phases of the cycle. Menstrual cycle phase had no significant effect on gaze-holding, optokinetic nystagmus slow phase velocity, amplitude or frequency, circularvection latency or optokinetic afternystagmus frequency, amplitude or duration. While menstrual cycle phase had no significant effect on anterior-posterior sway, it did significantly affect lateral sway (P<0...
July 20, 2001: Neuroscience Letters
L Todd, J King, C L Darlington, P F Smith
The aim of this study was to further investigate optokinetic reflex function in multiple sclerosis. Gaze-holding in darkness, optokinetic nystagmus, optokinetic afternystagmus and latency to circularvection were measured using electro-oculography and a rotating optokinetic drum. Gaze-holding was not significantly different between the multiple sclerosis and control groups; however, four of 23 multiple sclerosis patients exhibited eccentric gaze-evoked nystagmus. There were no significant differences in either optokinetic nystagmus frequency or latency to circularvection...
May 25, 2001: Neuroreport
K Peters, C L Darlington, P F Smith
Numerous animal studies have suggested that the vestibular system modulates respiratory and cardiovascular function. However, relatively few studies have examined vestibular-autonomic interaction in humans. In this study we investigated the effects of repeated horizontal (clockwise or anticlockwise) optokinetic stimulation on systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse and latency to circularvection (CV) in humans, and compared the effects with those of repeated exposure to a stationary visual stimulus...
2000: Journal of Vestibular Research: Equilibrium & Orientation
J Gowans, A Matheson, C L Darlington, P F Smith
The aim of the present study was to investigate the effects of scopolamine (1.5 mg, transdermal patch) and cyclizine (50 mg tablet), at the doses usually used for the relief of motion sickness, on postural sway, optokinetic nystagmus (OKN) and circularvection (CV) in humans, using a within-subjects, double-blind, placebo-controlled design. Scopolamine and cyclizine were found to have no significant suppressive effect on these aspects of visual-vestibular interaction. Postural sway and CV were not significantly affected by either drug treatment; OKN SPV was significantly increased (p < 0...
2000: Journal of Vestibular Research: Equilibrium & Orientation
C L Darlington, J Erasmus, M Nicholson, J King, P F Smith
We compared various measures of visual-vestibular interaction in subjects with insulin-dependent diabetes mellitus (IDDM) or non-insulin-dependent diabetes mellitus (NIDDM), as well as non-diabetic controls. Subjects with IDDM exhibited significantly greater postural sway than controls on those conditions in the Clinical Test of Sensory Interaction and Balance (CTSIB) which require greater reliance on the vestibular system (p < 0.005). The IDDM group also exhibited significantly worse gaze-holding in darkness and a significantly higher mean slow phase eye velocity (SPV) of optokinetic nystagmus (OKN; p<0...
February 28, 2000: Neuroreport
K V Thilo, T Probst, A M Bronstein, Y Ito, M A Gresty
Visual motion in the roll plane elicits torsional optokinetic nystagmus (tOKN) with intermittent periods of illusory, contradirectional self-motion (circularvection, CV). The CV may also have a component of whole-body tilt if the axis of stimulus rotation is not aligned with the direction of gravity. We report how the characteristics of tOKN are affected by the presence of CV. Subjects had their eye movements recorded by VOG whilst viewing a full-field stimulus rotating at 30-60 degrees/s about their naso-occipital axis...
June 1999: Experimental Brain Research. Experimentelle Hirnforschung. Expérimentation Cérébrale
K H McDermott, A J Matheson, N Titov, C L Darlington, P F Smith
Previous studies have shown that experience with optokinetic stimulation can alter a subject's sensitivity to illusions such as circularvection (CV). The aim of the present experiment was to compare optokinetic nystagmus (OKN), optokinetic afternystagmus (OKAN), and sensitivity to CV between 2 groups of sportspeople: 1) squash players (n = 16), who regularly experience vigorous optokinetic stimulation while engaging in their sporting activity, and 2) weightlifters (n = 16), whose sport does not involve the same degree of optokinetic stimulation as squash, but who nevertheless have to achieve a high degree of physical skill...
1999: Journal of Vestibular Research: Equilibrium & Orientation
B Cheung, P Vaitkus
Electrogastrography (EGG) is a noninvasive measurement of stomach activity using surface electrodes positioned over the abdominal surface. For over 10 years, EGG has been used as an objective measure of epigastric symptoms and nausea experienced in visually induced sickness provoked by circularvection. It was reported that during sickness, there is a shift in the dominant basal electrical activity. The 3 cycles per minute activity decrease and the 4-9 cycles per minute activity increase. This technique has also been used to evaluate the efficacy of antimotion sickness drugs and to monitor sickness induced by other provocative stimuli such as Coriolis cross-coupling, parabolic flight manoeuvres and microgravity...
November 15, 1998: Brain Research Bulletin
A J Matheson, C L Darlington, P F Smith
The aim of the present study was to investigate the effects of ageing on optokinetic function in labyrinthine-intact human subjects. Subjects aged 18-39 years, 40-59 years and > or = 60 years were tested for sensitivity to optokinetic stimulation using latency to the illusion of circularvection in an optokinetic drum. The latency to circularvection significantly increased with increasing age. These results suggest a decline in optokinetic sensitivity with increasing age, which may be related to age-related deterioration in the optokinetic visual pathways...
July 13, 1998: Neuroreport
C L Darlington, P F Smith
This paper reports further evidence that gender is a significant factor in the experience of circularvection (CV), the illusion of self-rotation. Using optokinetic drum velocities between 24 degrees and 92 degrees/s, latency to experience Stage 2 or Stage 3 CV was measured. Males exhibited significantly longer CV latencies than females (P < 0.0001), although the difference was greater for Stage 3 CV than for Stage 2 CV. This result suggests that the potential influence of gender must be carefully controlled in visual-vestibular interaction experiments...
March 1998: Journal of Vestibular Research: Equilibrium & Orientation
R S Kennedy, L J Hettinger, D L Harm, J M Ordy, W P Dunlap
Vection (V) refers to the compelling visual illusion of self-motion experienced by stationary individuals when viewing moving visual surrounds. The phenomenon is of theoretical interest because of its relevance for understanding the neural basis of ordinary self-motion perception, and of practical importance because it is the experience that makes simulation, virtual reality displays, and entertainment devices more vicarious. This experiment was performed to address whether an optokinetically induced vection illusion exhibits monotonic and stable psychometric properties and whether individuals differ reliably in these (V) perceptions...
September 1996: Journal of Vestibular Research: Equilibrium & Orientation
J M de Jong, W Bles, G Bovenkerk
Report on eye movements and perceived horizontal head rotation in 26 healthy students during sinusoidal vestibular, visual, cervical, congruent vestibular-plus-visual, or vestibular-plus-cervical stimulation. Circularvection occurred more often during neck afferent than during full-field optokinetic stimuli. In contrast, the cervico-ocular response had a low average velocity. As first noted by Frenzel (1928), a greater gaze shift distinguished the normal cervical from the normal labyrinthine response. The cervico-ocular and vestibulo-ocular responses were found to add up...
1981: Annals of the New York Academy of Sciences
U Büttner, V Henn
In psychophysical experiments, human subjects indicated the amount of circularvection (CV) that experienced during sinusoidal rotation (0.01-5 Hz) of the visual surround. Accelerations varied between 5 and 160 degrees/second2; maximal velocities did not exceed 160 degrees/second. Below 0.1 Hz and 20 degrees/second2, most subjects experienced full CV; above, CV was only partial. Subjects then perceived a combination of CV and object motion. All subjects still had some CV at 2 Hz. The upper frequency limit seemed to occur around 5 Hz...
1981: Annals of the New York Academy of Sciences
T Brandt, E Wist, J Dichgans
No abstract text is available yet for this article.
1971: Archiv Für Psychiatrie und Nervenkrankheiten
T Sekitani
Occurrence of circularvection and the disturbance of postural control in the fighter flight simulator were studied. The sensation of self-motion, circularvection, in the fighter flight simulator flying in a low-altitude and high-speed (but motionless base) was positive in all of four healthy male adult volunteers. Marked body staggering in the standing test was noted at post-flight. Square Drawing Test (hand writing test) showed some tendency of prolongation of lines, suggesting mis-calibration of fine hand-arm motor control...
March 1, 1985: Journal of UOEH
N G Page, M A Gresty
Six patients are described who experienced difficulty in driving a motor car. Four had illusions that the car was turning, which occurred particularly on open, featureless roads or the brows of hills and caused the driver to stop. All patients had peripheral or central neurootological abnormalities, but the only finding consistent with the directionality of the symptoms was an unpleasantly increased sense of circularvection during optokinetic stimulation in the direction of the illusion. These problems occur because of a false sense of orientation arising either from inappropriate signals from disordered vestibular canal and otolith organs or from a disordered central interpretation of vestibular information, and become manifest in the absence of adequate visual stabilisation...
August 1985: Journal of Neurology, Neurosurgery, and Psychiatry
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