Habtegiorgis Selam W, Rifai Katharina, Wahl Siegfried
Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.
J Vis. 2018 Jan 1;18(1):13. doi: 10.1167/18.1.13.
Spatially varying distortions in optical elements-for instance prisms and progressive power lenses-modulate the visual world disparately in different visual areas. Saccadic eye movements in such a complexly distorted environment thereby continuously alter the retinal location of the distortions. Yet the visual system achieves perceptual constancy by compensating for distortions irrespective of their retinal relocations at different fixations. Here, we assessed whether the visual system retains its plasticity to distortions across saccades to attain stability. Specifically, we tapped into reference frames of geometric skew-adaptation aftereffects to evaluate the transfer of retinotopic and spatiotopic distortion information across saccades. Adaptation to skew distortion of natural-image content was tested at retinotopic and spatiotopic locations after a saccade was executed between adaptation and test phases. The skew-adaptation information was partially transferred to a new fixation after a saccade. Significant adaptation aftereffects were obtained at both retinotopic and spatiotopic locations. Conceivably, spatiotopic information was used to counterbalance the saccadic retinal shifts of the distortions. Therefore, distortion processing in a natural visual world does not start anew at each fixation; rather, retinotopic and spatiotopic skew information acquired at previous fixations are preserved to mediate stable perception during eye movements.
光学元件中的空间变化失真——例如棱镜和渐变焦眼镜片——在不同视觉区域对视觉世界进行不同程度的调制。在这样一个复杂失真的环境中,眼球的扫视运动不断改变失真在视网膜上的位置。然而,视觉系统通过补偿失真来实现感知恒常性,而不管它们在不同注视点时在视网膜上的重新定位。在这里,我们评估了视觉系统是否保留了其对扫视运动中失真的可塑性以实现稳定性。具体来说,我们利用几何倾斜适应后效的参考框架来评估视网膜拓扑和空间拓扑失真信息在扫视运动中的传递。在适应阶段和测试阶段之间执行扫视运动后,在视网膜拓扑和空间拓扑位置测试对自然图像内容倾斜失真的适应情况。倾斜适应信息在扫视运动后部分转移到新的注视点。在视网膜拓扑和空间拓扑位置均获得了显著的适应后效。可以想象,空间拓扑信息被用来抵消失真在视网膜上的扫视移动。因此,在自然视觉世界中,失真处理并非在每次注视时都重新开始;相反,在先前注视中获得的视网膜拓扑和空间拓扑倾斜信息被保留下来,以在眼球运动过程中调节稳定的感知。