The effects of spatial offset, temporal offset and image speed on sensitivity to global motion in human amblyopia
The effects of spatial offset, temporal offset and image speed on sensitivity to global motion in human amblyopia
复制标题
DOI：
10.1016/j.visres.2013.04.003
复制
发表时间：
2013-06-28
期刊：
影响因子：
1.8
通讯作者：
Simmers, A. J.
中科院分区：
文献类型：
--
作者：
Knox, P. J.;Ledgeway, T.;Simmers, A. J.
弱视患者普遍存在全局运动处理缺陷，尽管其严重程度可能取决于图像速度和弱视类型，但其根本原因仍很大程度上不确定。为了解决这一问题，并进一步表征人类弱视中的全局运动感知缺陷的性质，评价了在弱视和正常视力中，对于一定范围的速度（1.5、3和9度/s），不同的空间偏移（跳跃大小-Δ s）和时间偏移（位置更新之间的延迟-Δ t）在区分全局运动中的影响。对于正常成人观察者（NE）和非弱视眼（FE）的运动相干阈值测量时，Δ t的变化显着高于当Δ s的变化。此外，当Δ t变化时，阈值随着内斯和FE的图像运动速度降低而显著升高。AE阈值总体上高于其他眼睛，并且似乎与用于创建运动和速度的方法无关。这些结果表明，空间和时间限制的整体运动的感知是不同的。此外，降低运动的平滑度对由AE驱动的运动机制的影响相对较小，这表明与编码运动方向相关联的内部噪声相对较高。(C)2013爱思唯尔有限公司保留所有权利。
The presence of a general global motion processing deficit in amblyopia is now well established, although its severity may depend on image speed and amblyopia type, but its underlying cause(s) is still largely indeterminate. To address this issue and to characterize further the nature of the global motion perception deficit in human amblyopia, the effects of varying spatial offset (jump size-Delta s) and temporal offset (delay between positional updates-Delta t) in discriminating global motion for a range of speeds (1.5, 3 and 9 degrees/s) in both amblyopic and normal vision were evaluated. For normal adult observers (NE) and the non-amblyopic eye (FE) motion coherence thresholds measured when Delta t was varied were significantly higher than those when Delta s was varied. Furthermore when Delta t was varied, thresholds rose significantly as the speed of image motion decreased for both NEs and FEs. AE thresholds were higher overall than the other eyes and appeared independent of both the method used to create movement and speed. These results suggest that the spatial and temporal limits underlying the perception of global motion are different. In addition degrading the smoothness of motion has comparatively little effect on the motion mechanisms driven by the AE, suggesting that the internal noise associated with encoding motion direction is relatively high. (C) 2013 Elsevier Ltd. All rights reserved.