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Monocular and Binocular Constraints on Eye Orientation
Published in Michael Fetter, Thomas Haslwanter, Hubert Misslisch, Douglas Tweed, Three-Dimensional Kinematics of Eye, Head and Limb Movements, 2020
A.V. van den Berg, P. Bruno, J.Tj.H.N. de Faber
Listing’s law is valid for eye fixation, smooth pursuit and saccades but the law is violated during compensatory eye movements like the VOR and the OKN. Listing’s law states that any eye orientation can be reached from a single reference orientation (the primary orientation) by rotation about an axis that is perpendicular both to the reference direction and to the current viewing direction. Together the rotation axes form a plane that is perpendicular to the primary direction (Nakayama, 1983; Ferman et al., 1987; Tweed and Vilis, 1990; Tweed et al., 1992; Haslwanter et al., 1991; Crawford and Vilis, 1992).
The evaluation of gravitational recognition in patients with spinocerebellar degeneration using Listing’s plane
Published in Acta Oto-Laryngologica, 2019
Takamori Takeda, Takuo Ikeda, Takeshi Tsutsumi
Eye movements can be described by a single-axis rotation. With one’s head remaining stationary, eye movement obeys Listing’s law, which proved that all axes about which the eye rotates from the primary position to other positions lie in one plane, known as Listing’s plane [5]. A number of studies have proven that the basic eye movement systems, such as fixation, saccade, and smooth pursuit, follow Listing’s law [6,7]. Characteristically, Listing’s plane moves in coincidence with the orientation of one’s head relative to gravity [8,9]. In fact, head tilt in the roll plane causes ocular counter-rolling, resulting in a shift of Listing’s plane back and forth, while head tilt in the pitch plane incline Listing’s plane in the direction opposite to the head orientation. The neural mechanism (or orbital structure by some reports) contributes to the implementation of Listing’s law, and the cerebellum plays a particularly important role in maintaining the eye position on Listing’s plane [10–12]. Therefore, cerebellum deficit leads to the violation of Listing’s law, resulting in the thickening of Listing’s plane [11,12]. In addition, illusory-inclination by optokinetic stimulation reduces the stability of gravitational recognition and also causes thickening of Listing’s plane [13]. Overall, the thickness of Listing’s plane could serve as a useful parameter with which to quantitatively evaluate the function of gravitational recognition constructed by the integration of visual, vestibular, and proprioceptive sensory input.
Why did Donders, after describing pseudotorsion, deny the existence of ocular counterrolling together with Ruete, Volkmann, von Graefe and von Helmholtz, until Javal reconfirmed its existence?
Published in Strabismus, 2018
What is the reason for one unique primary position, the starting point of eye rotation in Listing’s Law or, in other words, why is there a primary position, from which all other eye positions can be reached by simple rotation about a single axis or, in other words, why is the primary position not in left upper gaze, for instance? Von Helmholtz compared Listing’s Law and the primary position being in approximate gaze ahead with the minimal energy condition in physics.16 When the primary position is, approximately, the average position of the eye over the day, the least number of rotations are needed to rotate the eye. Most eye movements are directed radially from or to the primary position. During eye movement from one tertiary, left-down, for instance, to another tertiary position, right-down, for instance, Listing’s law is fulfilled only if the rotation takes place about an axis that is tilted to Listing’s plane by half the angle between the momentary eye position and primary position 16, hence an axis that changes during the eye movement.
About the rolling of the eye around the line of sight
Published in Strabismus, 2019
As can be seen from the table of deviations from Listing’s law listed by me in the specified reference, they do not appear only where they are effective, namely, in lowered plane of gaze, but in every position of the plane of gaze, even if they are ineffective or even counterproductive. If, for example, the lines of sight converge in the primary plane of gaze and the eyes would follow Listing’s law, the horizontal meridian would remain in the plane of gaze, which is most effective for single and clear vision in general. However, here too a deviation from Listing’s law occurs in the same sense as when gaze is lowered, which is the direction of gaze where the deviation is effective. If, on convergence in the primary plane of gaze, one is looking at an object which contains numerous horizontal contours, then, as long as convergence is small, the initial double images can be eliminated by a new rolling movement of the eyes in exactly the same way as in the experiments by Nagel. With stronger convergence in the primary plane of gaze, however, it is impossible to eliminate the double images. Those who have little observational acuity for such difficult-to-perceive double images can easily convince themselves, by setting a weak prism with the edge up or down before one eye, that the two images of a horizontal line or line do not run parallel in that case. Furthermore, as I have also explained in the specified reference and as Volkmann has stated, the deviation from Listing’s law occurs even in case of one-eyed vision where, of course, it serves no purpose, and even, as I have experienced, led to small apparent perceived motion, thus to a certainly not effective sensory illusion.