Journal: Journal of Neurophysiology

Article Title: Motion integration is anisotropic during smooth pursuit eye movements

doi: 10.1152/jn.00591.2018

Figure Lengend Snippet: A: the aperture problem. When a rigid object (i.e., the wavy black shape) is seen moving through a small window (i.e., holes on a semitransparent screen), its local motion is ambiguous, due to the lack of 2-dimensional features. The object global motion (red arrow) can be recovered by integrating local motion vectors orthogonal to the contours across space (blue arrows). B: stimulus used to simulate rigid object motion behind multiple circular windows. Gabor elements were randomly oriented and could drift at speeds that were only compatible with one global motion direction. Dashed lines were not shown. C: in velocity space, if the object motion is rigid, every motion vector length is determined by its orientation relative to the global motion direction, forming a circle. D: eye movement conditions. The observers either fixated a central dot or pursued it as it moved horizontally across the screen. The gratings drifted in the middle of the trajectory for 200 ms (cf. Fig. 2A), but the envelopes of the Gabor patches always moved at the same velocity as the target. If tracking were perfect, retinal motion would be the same in fixation and pursuit conditions.

Article Snippet: The multiple-aperture Gabor array ( Amano et al. 2009 ) shown in was composed of a grid of 744 Gabor patches displayed within two notional concentric circles around a 0.3° fixation point.

Techniques: Plasmid Preparation

Journal: Journal of Neurophysiology

Article Title: Motion integration is anisotropic during smooth pursuit eye movements

doi: 10.1152/jn.00591.2018

Figure Lengend Snippet: Stimulation time course in experiment 1. A: horizontal target position (top) and velocity (middle and bottom) are shown superimposed on the global motion (colored lines) of the grating pattern that was displayed behind multiple windows or apertures. The gratings moved with the pursuit target (or remained static during fixation) except for a 200-ms interval that is indicated by the dashed vertical lines. During this interval, the global motion speed of the gratings was ±2 deg/s relative to the target speed (5.72 deg/s). The blurred window through which each grating was viewed always moved at the same speed as the target (cf. Supplemental Movies S1–S4, https://doi.org/10.25392/leicester.data.7718453.v1). The colored lines refer to the velocity of the grating inside the window. B: unspeeded discrimination task. Gabor motion was either in the direction of pursuit (green arrows) or opposite to it (red arrows) and slightly upward or downward. At the end of the trial, observers reported whether they saw upward or downward global motion. C: composition of grating speeds to generate coherent global motion. Signal and noise velocity distribution are shown in velocity space. Signal gratings’ drift speed was compatible with either an upward (+10°; saturated color) or downward (−10°; unsaturated color) global motion component. The orientation of the global motion velocity vector relative to the horizontal is shown to scale. Observers discriminated vertical component direction at different levels of coherence (i.e., different amounts of signal relative to noise gratings).

Article Snippet: The multiple-aperture Gabor array ( Amano et al. 2009 ) shown in was composed of a grid of 744 Gabor patches displayed within two notional concentric circles around a 0.3° fixation point.

Techniques: Plasmid Preparation