Extraocular muscle proprioception functions in the control of ocular alignment and eye movement conjugacy

1994 ◽  
Vol 72 (2) ◽  
pp. 1028-1031 ◽  
Author(s):  
R. F. Lewis ◽  
D. S. Zee ◽  
B. M. Gaymard ◽  
B. L. Guthrie

1. The function of extraocular muscle proprioception in the control of eye movements is uncertain. We tested the hypothesis that proprioception contributes to the long-term regulation of ocular alignment and eye movement conjugacy. 2. Eye movements were recorded in monkeys with unilateral extraocular muscle palsies, before and after proprioceptive deafferentation of the paretic eye. Following deafferentation, ocular alignment and saccade conjugacy gradually worsened over several weeks. In contrast, disconjugate adaptation induced by habitual binocular viewing with a prism (disparity-mediated adaptation) occurred normally after deafferentation. 3. These results provide the first evidence that proprioception functions in the control of eye movements in primates, and indicate that proprioception contributes to the long-term adaptive mechanisms that regulate ocular alignment during fixation and saccades. The error signal used in this process may be derived from a mismatch between the efference copy and proprioceptive afference.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Talora L. Martin ◽  
Jordan Murray ◽  
Kiran Garg ◽  
Charles Gallagher ◽  
Aasef G. Shaikh ◽  
...  

AbstractWe evaluated the effects of strabismus repair on fixational eye movements (FEMs) and stereopsis recovery in patients with fusion maldevelopment nystagmus (FMN) and patients without nystagmus. Twenty-one patients with strabismus, twelve with FMN and nine without nystagmus, were tested before and after strabismus repair. Eye-movements were recorded during a gaze-holding task under monocular viewing conditions. Fast (fixational saccades and quick phases of nystagmus) and slow (inter-saccadic drifts and slow phases of nystagmus) FEMs and bivariate contour ellipse area (BCEA) were analyzed in the viewing and non-viewing eye. Strabismus repair improved the angle of strabismus in subjects with and without FMN, however patients without nystagmus were more likely to have improvement in stereoacuity. The fixational saccade amplitudes and intersaccadic drift velocities in both eyes decreased after strabismus repair in subjects without nystagmus. The slow phase velocities were higher in patients with FMN compared to inter-saccadic drifts in patients without nystagmus. There was no change in the BCEA after surgery in either group. In patients without nystagmus, the improvement of the binocular function (stereopsis), as well as decreased fixational saccade amplitude and intersaccadic drift velocity, could be due, at least partially, to central adaptive mechanisms rendered possible by surgical realignment of the eyes. The absence of improvement in patients with FMN post strabismus repair likely suggests the lack of such adaptive mechanisms in patients with early onset infantile strabismus. Assessment of fixation eye movement characteristics can be a useful tool to predict functional improvement post strabismus repair.


Perception ◽  
1981 ◽  
Vol 10 (6) ◽  
pp. 615-626
Author(s):  
Judith Callan ◽  
Sheldon M Ebenholtz

Records were taken of the horizontal and vertical amplitudes of eye movements of subjects instructed to move their eyes back and forth from 12 to 6 and from 9 to 3 o'clock without targets. These records were used to compute the angles of the eye-movement paths, and corresponding paths were compared before and after exposure in a hallway to a prism-induced clockwise tilt of 30°. Perceived orientation was also measured, by having the subjects set a luminous line in the dark to the orientations indicated above. Both tasks yielded significant preexposure—postexposure changes in the direction of tilt, such that after exposure the line was set at a tilt and eye movements were made at an angle clockwise with respect to the preexposure orientation. A control group exposed to 0° tilt showed no change on either task. Thus, tilt adaptation is capable of altering the direction of volitional eye movements.


1977 ◽  
Vol 44 (3) ◽  
pp. 683-689 ◽  
Author(s):  
Amos S. Cohen ◽  
Herbert Studach

The eye fixations of 5 experienced and 4 inexperienced car drivers were analyzed while driving curves to the left and to the right. For experienced drivers in a curve to the left the mean duration of eye fixations was longer and the amplitude of the eye movements greater than in a curve to the right. No such difference was observed in inexperienced drivers who manifested neither uniformity within the same curves nor differentiation between the two types of curves. Mean duration of eye fixations of experienced subjects was shorter while driving in a curve to right, but their amplitude of eye movement was greater in a curve to left than those of inexperienced drivers. In Exp. 2, it was pointed out that there is already a change in the pattern of eye movements prior to entering a curve. Upon approaching the curve the mean duration of eye fixation decreased, and the fixations were mainly shifted toward the future driving path. Results are interpreted in terms of the adequacy of the eye fixations (supposedly influenced by prior long-term learning) for information at near distance for vehicle control and at longer distances for setting up proprioceptive forward programs for possible future sensomotoric activity.


2003 ◽  
Vol 90 (6) ◽  
pp. 3809-3815 ◽  
Author(s):  
Diana M. Dimitrova ◽  
Mary S. Shall ◽  
Stephen J. Goldberg

Recent studies have suggested that extraocular muscle (EOM) pulleys, composed of collagen, elastin, and smooth muscle, are among the tissues surrounding the eye. High-resolution magnetic-resonance imaging appears to indicate that the pulleys serve to both constrain and alter the pulling paths of the EOMs. The active pulley hypothesis suggests that the orbital layer of the EOMs inserts on the pulley and serves to control it. Based on anatomical data, the active pulley hypothesis also suggests that the orbital layer does not rotate the eye within the orbit; this is done by the global layer of the muscle. However, no physiological data exist to confirm this hypothesis. Here we used stimulation-evoked eye movements in anesthetized monkeys and cats before and after destruction of the lateral rectus muscle pulley by removal of the lateral bony orbit and adjacent orbital tissue. The absence of these structures resulted in increased lateral, in the primate, and medial, in the cat, eye-movement amplitude and velocity. Vertical eye movements in the cat were not significantly affected. The results indicate that these increases, confined to horizontal eye-movement amplitude and velocity, may be attributed to passive properties within the orbit. In relation to the active pulley hypothesis, we could discern no clear impact (in terms of amplitude or velocity profile of the movements) of lateral eye exposure that could be directly attributable to the active lateral pulley system.


1992 ◽  
Vol 68 (5) ◽  
pp. 1913-1916 ◽  
Author(s):  
J. C. Lynch

1. Monkeys were trained to perform horizontal visually guided saccades. Latency was measured before and after bilateral lesions of the frontal eye field (FEF) and after combined lesions of both the FEF and the posterior eye field. Destruction of either of these regions alone causes only modest deficits of eye movement, but destruction of both together produces profound oculomotor impairment. The results support the proposal that purposeful eye movements are controlled by a distributed corticocortical network that includes nodes in frontal and parieto-occipital regions.


1971 ◽  
Vol 54 (2) ◽  
pp. 403-414
Author(s):  
J. R. JOHNSTONE ◽  
R. F. MARK

1. Neurones which fire at the same time as saccades are found in the tectal commissure of carp. They are unaffected by visual stimuli or by paralysis of eye muscles and so their activity is not directly related to sensory input. 2. Twenty-two units have been examined. They fire in bursts only during eye movements and only for a particular direction of movement, either eyes-left or eyes-right. They begin to fire a few milliseconds before eye movement begins, slowly at first, reach a maximum frequency of about 300 Hz, then slow again and stop after about 100 ms. 3. In two instances such units have been recorded simultaneously in paralysed fish with a tonically firing unit, presumably visual, which was suppressed during each burst. In one case the tonic activity after each burst was increased, in the other it was decreased. 4. We suggest they are efference copy neurones, responsible for perceptual stability during eye movements. Their possible function is discussed in detail. They are not tectal motoneurones because the same eye movements continue after total removal of the tectum. Neither are they dependent on sensory input resulting from eye movement because their discharge patterns are unaffected by darkness or paralysis.


PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0243752
Author(s):  
Christoph von Laßberg ◽  
Jennifer L. Campos ◽  
Karl A. Beykirch

In a prior publication, we described a previously unknown eye movement phenomenon during the execution of actively performed multiaxial rotations in high level gymnasts. This phenomenon was consistently observed during the phase of fast free flight rotations and was marked by a prolonged and complete suppression of nystagmus and gaze stabilizing “environment referenced eye movements” (EREM; such as the vestibulo-ocular reflex, optokinetic reflex, smooth pursuit and others). Instead, these eye movements were coupled with intersegmental body movements. We have therefore called it “spinal motor-coupled eye movements” (SCEM) and have interpreted the phenomenon to likely be caused by anti-compensatory functions of more proprioceptive mediated reflexes and perhaps other mechanisms (e.g., top-down regulation as part of a motor plan) to effectively cope with a new-orientation in space, undisturbed by EREM functions. In the phase before landing, the phenomenon was replaced again by the known gaze-stabilizing EREM functions. The present study specifically evaluated long-term measures of vestibulo-ocular reflex functions (VOR) in high level gymnasts and controls during both passively driven monoaxial rotations and context-specific multiaxial somersault simulations in a vestibular lab. This approach provided further insights into the possible roles of adaptive or mental influences concerning the VOR function and how they are associated with the described phenomenon of SCEM. Results showed high inter-individual variability of VOR function in both gymnasts and controls, but no systematic adaptation of the VOR in gymnasts, neither compared to controls nor over a period of three years. This might generally support the hypothesis that the phenomenon of SCEM might indeed be driven more by proprioceptively mediated and situationally dominant eye movement functions than by adaptative processes of the VOR.


1984 ◽  
Vol 51 (4) ◽  
pp. 649-665 ◽  
Author(s):  
K. Toyama ◽  
Y. Komatsu ◽  
K. Shibuki

Responses of saccade-depressed (SD) and saccade-excited (SE) cells in the striate cortex to eye movements of alert cats under presentation of a visual pattern were studied under reinforcement of the eye movements with rewards of water. These responses were compared to those on passive displacement of the visual pattern reproducing the movements of the retinal image occurring during eye movements while eye movements were suppressed by withdrawal of reinforcement. Passive displacement of the visual pattern produced in the SD cells depression closely resembled the depression occurring during eye movements under presentation of the visual pattern, in time course as well as in amplitude. Both the saccade depression and the depression due to passive movement of the visual pattern were nonselective to the direction of eye movements. Saccade excitation of the SE cells frequently contained two components occurring at 20 and 80 ms after the onsets of eye movements. Passive displacement of the visual pattern produced in the SE cells excitation comparable with the early component of the saccade excitation. These findings suggest that saccade depression in the SD cells and the early component of the saccade excitation in the SE cells are related to retinal reafference of eye movement. During presentation of visual patterns, saccade excitation in the SE cells was closely related to parameters of eye movements, such as direction, amplitude, duration, and velocity. The correlations were completely lost or strongly reduced in darkness. Lines of evidence were provided that the saccade excitation of the SE cells in darkness or the later component of the saccade excitation under presentation of a visual pattern represents efference copy signals of eye movement transferred to the striate cortex through the Clare-Bishop (CB) cortex. Excitation comparable with saccade excitation in darkness occurred in synchrony with activities of the oculomotor nuclei even after retrobulbar paralysis of eye movement, indicating that the excitation is related to efference copy signals rather than proprioceptive reafference of eye movement.(ABSTRACT TRUNCATED AT 400 WORDS)


2011 ◽  
Vol 5 (4) ◽  
pp. 146-155 ◽  
Author(s):  
Hellen K. Hornsveld ◽  
Jan. H. Houtveen ◽  
Max Vroomen ◽  
Immanuel Kapteijn ◽  
Dorienke Aalbers ◽  
...  

Resource development and installation (RDI) is an eye movement desensitization and reprocessing (EMDR)-related procedure developed to strengthen positive associations in positive and resourceful memories (Korn & Leeds, 2002). This study tested the assumption that bilateral stimulation (horizontal eye movements [EM]) in RDI “appears to lead to spontaneous, rapid increases in affective intensity . . . and to rich, emotionally vivid associations” (Korn & Leeds, p. 1469). This study also tested whether eye movement effects could be better accounted for by working memory or by interhemispheric interaction theory. Fifty-three undergraduate students each recalled three memories of pride, perseverance, and self-confidence. They provided pretest and posttest ratings of each memory for vividness, pleasantness, and experienced strength of the positive quality, before and after performing three simultaneous tasks during recall: horizontal EM, vertical EM, and recall only. Results were fully in line with working memory predictions, with significant decreases for all variables following both eye movement tasks. There was no support for the interhemispheric hypothesis. It is concluded that the effectiveness of bilateral stimulation in RDI is questionable. Clinical implications are discussed.


2009 ◽  
Vol 3 (2) ◽  
Author(s):  
Gary Feng

This paper investigates why the average fixation duration tends to decrease from the center to the two ends of a word. Specifically, it examines (a) whether unfavorable landing positions trigger a corrective mechanism, (b) whether the triggering is based on the internal efference copy mechanism, and (c) whether the corrective mechanism is specific to fixations that missed their targeted words. To estimate the mean and proportion of the corrective fixations, a 3-parameter mixture model was fitted to distributions of first fixation duration from two large eye movement databases in studies 1 and 2. Study 3 experimentally created mislocated fixations using a gaze-contingent screen shift paradigm. There is little evidence for the efference copy mechanism and limited support for the mislocated fixations hypothesis. Overall, data suggest a process that terminates fixations sooner than would during normal reading; it is triggered by the visual input during a fixation, and is flexibly engaged at eccentric landing positions and in reading short words. Implications to theories of reading eye movements are discussed.


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