Enhanced vestibulo-ocular reflex suppression in dancers during passive high-velocity head impulses

Background and Aim: One of the tools for assessing the vestibulo-ocular reflex (VOR) is using video head impulse test (vHIT). In this test by placing the head at different angles and shaking the head, three semicircular canals of the vestibular system in each ear can be examined separately. The purpose of this study was to investigate the relationship between the low and high velocities of the vHIT test with VOR and its compensatory saccades. Methods: The vHIT test was performed by an examiner in 49 normal individuals aged 23–39 at low and high velocities. All participants had normal hearing, visual, and vestibular systems. Results: Mean gains in the horizontal, anterior and posterior semicircular canals in the right ear respectively were 0.92, 1 and 0.90 and in the left ear 0.93, 0.99 and 0.95 for low velocity and 0.78, 0.92 and 0.79 in the right ear and 0.80, 0.85 and 0.86 in the left ear for high velocity. Also, the number of compensatory saccade at high velocity was higher than those at the low velocity and the latency of compensatory saccade was lower at the higher velocity. Conclusion: In the vHIT test, VOR gain decreases at high velocity that is statistically significant. Also, compensatory saccades are more likely to occur at high velocity with smaller delay. Therefore, high-velocity vHIT test is not recommended for the purpose of examining the VOR gain and compensatory saccade.

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The Effect of Different Head Movement Paradigms on Vestibulo-Ocular Reflex Gain and Saccadic Eye Responses in the Suppression Head Impulse Test in Healthy Adult Volunteers

Frontiers in Neurology ◽

10.3389/fneur.2021.729081 ◽

2021 ◽

Vol 12 ◽

Author(s):

Dmitrii Starkov ◽

Bernd Vermorken ◽

T. S. Van Dooren ◽

Lisa Van Stiphout ◽

Miranda Janssen ◽

...

Keyword(s):

Healthy Subjects ◽

Healthy Adult ◽

Head Movements ◽

Head Impulse Test ◽

Head Impulse ◽

Ocular Reflex ◽

Vestibulo Ocular Reflex ◽

Reflex Gain ◽

Head Impulses ◽

Adult Volunteers

Objective: This study aimed to identify differences in vestibulo-ocular reflex gain (VOR gain) and saccadic response in the suppression head impulse paradigm (SHIMP) between predictable and less predictable head movements, in a group of healthy subjects. It was hypothesized that higher prediction could lead to a lower VOR gain, a shorter saccadic latency, and higher grouping of saccades.Methods: Sixty-two healthy subjects were tested using the video head impulse test and SHIMPs in four conditions: active and passive head movements for both inward and outward directions. VOR gain, latency of the first saccade, and the level of saccade grouping (PR-score) were compared among conditions. Inward and active head movements were considered to be more predictable than outward and passive head movements.Results: After validation, results of 57 tested subjects were analyzed. Mean VOR gain was significantly lower for inward passive compared with outward passive head impulses (p < 0.001), and it was higher for active compared with passive head impulses (both inward and outward) (p ≤ 0.024). Mean latency of the first saccade was significantly shorter for inward active compared with inward passive (p ≤ 0.001) and for inward passive compared with outward passive head impulses (p = 0.012). Mean PR-score was only significantly higher in active outward than in active inward head impulses (p = 0.004).Conclusion: For SHIMP, a higher predictability in head movements lowered gain only in passive impulses and shortened latencies of compensatory saccades overall. For active impulses, gain calculation was affected by short-latency compensatory saccades, hindering reliable comparison with gains of passive impulses. Predictability did not substantially influence grouping of compensatory saccades.

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Effect of common antivertiginous agents on the high velocity vestibulo-ocular reflex

Clinical Neurophysiology ◽

10.1016/j.clinph.2017.08.025 ◽

2017 ◽

Vol 128 (11) ◽

pp. 2211-2216 ◽

Cited By ~ 1

Author(s):

E. Anagnostou ◽

P. Koutsoudaki ◽

A. Stavropoulos ◽

I. Evdokimidis

Keyword(s):

High Velocity ◽

Ocular Reflex ◽

Vestibulo Ocular Reflex

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High-Velocity Angular Vestibulo-Ocular Reflex Adaptation to Position Error Signals

Journal of Neurologic Physical Therapy ◽

10.1097/npt.0b013e3181dde7bc ◽

2010 ◽

Vol 34 (2) ◽

pp. 82-86 ◽

Cited By ~ 5

Author(s):

Matthew Scherer ◽

Michael C. Schubert

Keyword(s):

High Velocity ◽

Position Error ◽

Ocular Reflex ◽

Vestibulo Ocular Reflex

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Head Impulses After Unilateral Vestibular Deafferentation Validate Ewald’s Second Law1

Journal of Vestibular Research ◽

10.3233/ves-1991-1210 ◽

1991 ◽

Vol 1 (2) ◽

pp. 187-197

Author(s):

G.M. Halmagyi ◽

I.S. Curthoys ◽

P.D. Cremer ◽

C.J. Henderson ◽

M. Staples

Keyword(s):

Head Rotation ◽

Normal Subjects ◽

Head Movements ◽

Afferent Neurons ◽

Horizontal Semicircular Canal ◽

Ocular Reflex ◽

Vestibulo Ocular Reflex ◽

Unilateral Vestibular Deafferentation ◽

Head Impulses ◽

Stimulation Of

To determine the relative contributions of ampullofugal (AF) and ampullopetal (AP) stimulation of the horizontal semicircular canal (HSCC) to the horizontal vestibulo-ocular reflex (HVOR), 12 patients were studied 1 year after total unilateral vestibular deafferentation (UVD). Compensatory eye movement responses to impulses of horizontal head rotation were studied using magnetic search coils. The head impulses were rapid (up to 3000 deg/sec/sec) passive, unpredictable, step displacements of horizontal angular head position with respect to the trunk. Tbe results from these 12 patients were compared with results from 30 normal subjects. An HVOR deficit was found to each side. The HVOR in response to head impulses toward the deafferented side, a response generated exclusively by ampullofugal stimulation of the single functioning HSCC, was severely deficient with an average gain of 0.25; the HVOR in response to head impulses toward the intact side, a response generated exclusively by ampullopetal stimulation of the single functioning HSCC, was mildly but significantly deficient compared with normal subjects. These results show that rapid, unpredictable head movements, unlike slow, predictable head movements, do demonstrate the AP-AF HVOR asymmetry, which could be expected from consideration of the behavior of single vestibular afferent neurons, an asymmetry that is expressed by Ewald’s 2nd Law.

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