Cross-coupling between horizontal and vertical eye movements during optokinetic nystagmus and optokinetic afternystagmus elicited in microgravity

Different types of fast eye movements, including saccades and fast phases of optokinetic nystagmus (OKN) and optokinetic afternystagmus (OKAN), are coded by only partially overlapping neural networks. This is a likely cause for the differences that have been reported for the dynamic parameters of fast eye movements. The dependence of two of these parameters—peak velocity and duration—on saccadic amplitude has been termed “main sequence.” The main sequence of OKAN fast phases has not yet been analyzed. These eye movements are unique in that they are generated by purely subcortical control mechanisms and that they occur in complete darkness. In this study, we recorded fast phases of OKAN and OKN as well as visually guided and spontaneous saccades under identical background conditions because background characteristics have been reported to influence the main sequence of saccades. Our data clearly show that fast phases of OKAN and OKN differ with respect to their main sequence. OKAN fast phases were characterized by their lower peak velocities and longer durations compared with those of OKN fast phases. Furthermore we found that the main sequence of spontaneous saccades depends heavily on background characteristics, with saccades in darkness being slower and lasting longer. On the contrary, the main sequence of visually guided saccades depended on background characteristics only very slightly. This implies that the existence of a visual saccade target largely cancels out the effect of background luminance. Our data underline the critical role of environmental conditions (light vs. darkness), behavioral tasks (e.g., spontaneous vs. visually guided), and the underlying neural networks for the exact spatiotemporal characteristics of fast eye movements.

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Oculomotor Reactions in the Cuttlefish, Sepia Officinalis

Journal of Experimental Biology ◽

10.1242/jeb.52.2.369 ◽

1970 ◽

Vol 52 (2) ◽

pp. 369-384 ◽

Cited By ~ 3

Author(s):

H. COLLEWIJN

Keyword(s):

Eye Movements ◽

Optokinetic Nystagmus ◽

Eye Position ◽

Sepia Officinalis ◽

Search Coil ◽

Passive Rotation ◽

Eye Velocity ◽

Search Coil Technique ◽

Better Than

1. Eye position in Sepia was measured in restrained animals, using a scleral search coil technique. 2. Optokinetic nystagmus was elicited by drum rotations from 0.035 up to 35°/sec. 3. Passive rotation of Sepia in darkness evoked a transient nystagmus, followed by after-nystagmus at arrest. 4. Combination of these two stimuli yielded the best results, but the ratio eye velocity/surroundings velocity was usually not better than 0.5. 5. Eye movements were conjugate and a closed eye could be driven by a seeing eye. Monocular reactions were smaller than binocular ones, but equal in both directions. 6. Fixation movements could not be demonstrated in the present conditions.

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Establishing an Objective Measurement of Visual Acuity with a Computerised Optokinetic Nystagmus Suppression Test

Klinische Monatsblätter für Augenheilkunde ◽

10.1055/a-1119-6123 ◽

2020 ◽

Vol 237 (04) ◽

pp. 502-505

Author(s):

Noemie Schwob ◽

Anja Palmowski-Wolfe

Keyword(s):

Visual Acuity ◽

Eye Movements ◽

Optokinetic Nystagmus ◽

Objective Measurement ◽

Mean Difference ◽

Alternative Option ◽

Snellen Acuity ◽

Suppression Test ◽

Infrared Cameras ◽

Acuity Test

Abstract Objective Investigating the correlation between subjective and objective VA (visual acuity) elicited with a newly developed computerised optokinetic nystagmus (OKN) suppression test (“SpeedWheel”) in adults. Methods SpeedWheel presented alternating black/white stripes moving horizontally across a LED screen. Seven VA steps were induced with Bangerter filters placed onto spectacle frames. Magnified eye movements were projected from infrared cameras inside the frames and displayed onto a smartphone. Dots whose size increased in logarithmic steps were superimposed to suppress OKN. Suppression of OKN resulted in the SpeedWheel acuity which was then correlated to Snellen acuity as measured with the Freiburg Acuity test. Results 28 eyes from 14 individuals were tested. FrACT-E correlated well to SpeedWheel (r: 0.89; p < 0.001). Snellen acuity was never lower than 0.14 LogMAR of SpeedWheel values. Bangerter filters showed greater mean difference to both methods indicating that this filter is not as predictable as suggested by the filter value. Conclusion SpeedWheel offers a fast (< 80 sec) and reliable alternative option to measure objective VA.

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Optokinetic nystagmus in patients with SCA

Neurology ◽

10.1212/wnl.0000000000006250 ◽

2018 ◽

Vol 91 (13) ◽

pp. e1255-e1261 ◽

Cited By ~ 3

Author(s):

Doniparthi V. Seshagiri ◽

Pramod Kumar Pal ◽

Sanjeev Jain ◽

Ravi Yadav

Keyword(s):

Eye Movements ◽

Prospective Observational Study ◽

Rating Scale ◽

Optokinetic Nystagmus ◽

Neurologic Examination ◽

Clinical Tool ◽

Motor Disability ◽

Tendon Reflexes ◽

Sensitive Marker

ObjectiveTo characterize the clinical features in patients with spinocerebellar ataxia (SCA) type 1, SCA2, and SCA3 and to evaluate the oculomotor dysfunction by using optokinetic nystagmus (OKN) testing, which may be a sensitive marker.MethodsIn this prospective observational study, all patients underwent detailed neurologic examination with special emphasis on eye movements. OKN was evaluated with a tape. Disease severity was measured with the International Co-Operative Ataxia Rating Scale (ICARS).ResultsA total of 73 genetically confirmed patients were included, of whom 28, 30, and 15 patients were positive for SCA1, SCA2, and SCA3, respectively. Dystonia was more common in patients with SCA3 (46%), and absent ankle jerk was more common in those with SCA2 (21.4%). Brisk deep tendon reflexes were common in patients with SCA1 (46.6%), followed by patients with SCA3 (26.6%) and SCA2 (7.1%). Vertical OKN was impaired in all patients and absent in 86.6% of patients with SCA1, 96% of those with SCA2, and 80% of those with SCA3. Horizontal OKN was absent in 30% of patients with SCA1, 57% of patients with SCA2, and 33% of those with SCA3. Higher motor disability (posture and gait, kinetic functions [Motor Disability] subscore on the ICARS) was associated with higher oculomotor dysfunction measured by OKN-saccades impairment grading but not with the Ocular Disorder subscore of ICARS (ICARS-OD).ConclusionOKN-saccades are a better and sensitive bedside clinical tool to quantify oculomotor dysfunction in neurodegenerative ataxias. Its role needs to be tested further in presymptomatic carriers. The current ICARS-OD scale to grade oculomotor dysfunction in degenerative ataxias need to be modified.

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Lesions of the posterior commissure disable the vertical neural integrator of the primate oculomotor system

Journal of Neurophysiology ◽

10.1152/jn.1994.71.6.2582 ◽

1994 ◽

Vol 71 (6) ◽

pp. 2582-2585 ◽

Cited By ~ 21

Author(s):

A. M. Partsalis ◽

S. M. Highstein ◽

A. K. Moschovakis

Keyword(s):

Eye Movements ◽

Optokinetic Nystagmus ◽

Head Rotation ◽

Oculomotor System ◽

Squirrel Monkeys ◽

Neural Integrator ◽

Posterior Commissure ◽

Oculomotor Neurons ◽

Before And After ◽

Gain Reduction

1. Spontaneous saccades, vestibuloocular responses (VOR), and optokinetic nystagmus were recorded in three squirrel monkeys before and after chemical or electrolytic lesion of the posterior commissure (PC). 2. PC lesions produced abnormal vertical eye movements, in particular, 1) Postsaccadic drifts, and 2) VOR gain reduction and phase advance more pronounced at lower frequencies of sinusoidal head rotation. Horizontal eye movements were much less affected (or normal). 3. We conclude that PC fibers are necessary for conveying the output of the vertical neural integrator to vertical oculomotor-neurons.

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Eye Movements in Cerebellar and Combined Cerebellobrainstem Diseases

Annals of Otology Rhinology & Laryngology ◽

10.1177/000348948309200214 ◽

1983 ◽

Vol 92 (2) ◽

pp. 165-171 ◽

Cited By ~ 14

Author(s):

Carsten Wennmo ◽

Bengt Hindfelt ◽

Ilmari Pyykkö

Keyword(s):

Quantitative Analysis ◽

Eye Movements ◽

Eye Movement ◽

Smooth Pursuit ◽

Optokinetic Nystagmus ◽

Vestibular Nystagmus ◽

Full Field ◽

Eye Velocity ◽

Voluntary Saccades ◽

Cerebellar Disorders

We report a quantitative analysis of eye movement disturbances in patients with isolated cerebellar disorders and patients with cerebellar disorders and concomitant brainstem involvement. The most characteristic abnormalities in the exclusively cerebellar patients were increased velocities of the slow phases of vestibular nystagmus induced by rotation in the dark and increased peak velocities of the fast phases of optokinetic nystagmus induced by full-field optokinetic stimuli. Dysmetria of saccades was found in three of six cerebellar patients and gaze nystagmus in all six patients. The typical findings in the combined cerebellobrainstem group were reduced peak velocities of voluntary saccades, defective smooth pursuit and reduced peak velocities of the fast component of nystagmus during rotation in both the dark and light. All patients with combined cerebellobrainstem disorder had dysmetric voluntary saccades and gaze nystagmus. The numbers of superimposed saccades during smooth pursuit were uniformly increased. Release of inhibition in cerebellar disorders may explain the hyperresponsiveness and inaccuracy of eye movements found in this study. In addition, when lesions also involve the brainstem, however, integrative centers coding eye velocity are affected, leading to slow and inaccurate eye movements. These features elicited clinically may be useful in the diagnosis of cerebellar and brainstem disorders.

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Motion defined exclusively by second-order characteristics does not evoke optokinetic nystagmus

Visual Neuroscience ◽

10.1017/s0952523800001802 ◽

1992 ◽

Vol 9 (6) ◽

pp. 565-570 ◽

Cited By ~ 47

Author(s):

Laurence R. Harri ◽

Andrew T. Smith

Keyword(s):

Eye Movements ◽

Smooth Pursuit ◽

Optokinetic Nystagmus ◽

Second Order ◽

Smooth Pursuit Eye Movements ◽

High Contrast ◽

Apparent Contrast ◽

First Order ◽

Pursuit Eye Movements

AbstractWe showed high-contrast, second-order motion stimuli to subjects whilst recording their horizontal eye movements. These stimuli were very poor at evoking optokinetic nystagmus. Smooth-pursuit eye movements and fixation were reduced by a masking band ±2.5 deg above and below an imaginary fixation point. First-order stimuli evoked vigorous optokinetic nystagmus (OKN) under identical conditions and also when matched for apparent contrast. These findings are discussed in terms of the site of detection of second-order motion.

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Reversed Visual Motion and Self-Sustaining Eye Oscillations

Perception ◽

10.1068/p260823 ◽

1997 ◽

Vol 26 (7) ◽

pp. 823-830 ◽

Cited By ~ 7

Author(s):

Lothar Spillmann ◽

Stuart Anstis ◽

Anne Kurtenbach ◽

Ian Howard

Keyword(s):

Eye Movements ◽

Flow Field ◽

Negative Feedback ◽

Positive Feedback ◽

Optic Flow ◽

Visual Motion ◽

Optokinetic Nystagmus ◽

Retinal Images ◽

Wide Range ◽

Reversed Motion

A random-dot field undergoing counterphase flicker paradoxically appears to move in the same direction as head and eye movements, ie opposite to the optic-flow field. The effect is robust and occurs over a wide range of flicker rates and pixel sizes. The phenomenon can be explained by reversed phi motion caused by apparent pixel movement between successive retinal images. The reversed motion provides a positive feedback control of the display, whereas under normal conditions retinal signals provide a negative feedback. This altered polarity invokes self-sustaining eye movements akin to involuntary optokinetic nystagmus.

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Right frontal eye field has perceptual and oculomotor functions during optokinetic stimulation and nystagmus

Journal of Neurophysiology ◽

10.1152/jn.00468.2019 ◽

2020 ◽

Vol 123 (2) ◽

pp. 571-586 ◽

Cited By ~ 1

Author(s):

Angela Mastropasqua ◽

James Dowsett ◽

Marianne Dieterich ◽

Paul C. J. Taylor

Keyword(s):

Eye Movements ◽

Transcranial Magnetic Stimulation ◽

Magnetic Stimulation ◽

Visual Motion ◽

Optokinetic Nystagmus ◽

Frontal Eye Field ◽

Optokinetic Stimulation ◽

Motion Discrimination ◽

Eye Field ◽

The Right

The right frontal eye field (rFEF) is associated with visual perception and eye movements. rFEF is activated during optokinetic nystagmus (OKN), a reflex that moves the eye in response to visual motion (optokinetic stimulation, OKS). It remains unclear whether rFEF plays causal perceptual and/or oculomotor roles during OKS and OKN. To test this, participants viewed a leftward-moving visual scene of vertical bars and judged whether a flashed dot was moving. Single pulses of transcranial magnetic stimulation (TMS) were applied to rFEF on half of trials. In half of blocks, to explore oculomotor control, participants performed an OKN in response to the OKS. rFEF TMS, during OKN, made participants more accurate on trials when the dot was still, and it slowed eye movements. In separate blocks, participants fixated during OKS. This not only controlled for eye movements but also allowed the use of EEG to explore the FEF’s role in visual motion discrimination. In these blocks, by contrast, leftward dot motion discrimination was impaired, associated with a disruption of the frontal-posterior balance in alpha-band oscillations. None of these effects occurred in a control site (M1) experiment. These results demonstrate multiple related yet dissociable causal roles of the right FEF during optokinetic stimulation. NEW & NOTEWORTHY This study demonstrates causal roles of the right frontal eye field (FEF) in motion discrimination and eye movement control during visual scene motion: previous work had only examined other stimuli and eye movements such as saccades. Using combined transcranial magnetic stimulation and EEG and a novel optokinetic stimulation motion-discrimination task, we find evidence for multiple related yet dissociable causal roles within the FEF: perceptual processing during optokinetic stimulation, generation of the optokinetic nystagmus, and the maintenance of alpha oscillations.

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Eye movements in Daphnia pulex (De Geer)

Journal of Experimental Biology ◽

10.1242/jeb.62.1.175 ◽

1975 ◽

Vol 62 (1) ◽

pp. 175-187

Author(s):

BJ Frost

Keyword(s):

Eye Movements ◽

Fourier Analysis ◽

Eye Movement ◽

Horizontal Plane ◽

High Speed ◽

Optokinetic Nystagmus ◽

Sagittal Plane ◽

Daphnia Pulex ◽

Saccadic Eye Movements ◽

Fourth Harmonic

1. The various types of eye movement exhibited by the cyclopean eye of Daphnia pulex were studied using high speed motion photography. 2. This rudimentary eye, which consists of only 22 ommatidia, can move through approximately 150 degrees in the sagittal plane and 60 degrees in the horizontal plane. 3. Four classes of eye movement were found: (1) a high speed tremor at 16 Hz with an amplitude of 3-4 degrees, which resembles physiological nystagmus, (2) a slow rhythmic scanning movement at 4 Hz, and 5-6 degrees amplitude, (3) large fast eye movements similar to saccadic eye movements and (4) optokinetic nystagmus produced by moving striped patterns. 4. Where the fast tremor occurred concurrently with the slow rhythmic scan, a Fourier analysis revealed that the former was the fourth harmonic of the latter.

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