Perceptual and Cognitive Dynamics Laboratory, Department of Electrical & Computer Engineering, University of Denver, Denver, CO 80208, USA.
Laboratory of Psychophysics, Brain Mind Institute, École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
Vision Res. 2020 Sep;174:10-21. doi: 10.1016/j.visres.2020.05.007. Epub 2020 Jun 4.
The early visual system is organized retinotopically. However, under ecological viewing conditions, motion perception occurs in non-retinotopic coordinates. Even though many studies revealed the central role of non-retinotopic processes, very little is known about their mechanisms and neural correlates. Tadin and colleagues found that increasing the spatial size of a high-contrast drifting-Gabor deteriorates motion-direction discrimination, whereas the opposite occurs with a low-contrast stimulus. The results were proposed to reflect an adaptive center-surround antagonism, whereby at low-contrast the excitatory center dominates whereas at high-contrast suppressive-surround mechanisms become more effective. Because ecological vision is non-retinotopic, we tested the hypothesis that the non-retinotopic system also processes motion information by means of an adaptive center-surround mechanism. We used the Ternus-Pikler display designed to provide either a retinotopic or a non-retinotopic reference-frame. Our results suggest that the non-retinotopic processes underlying motion perception are also mediated by an adaptive center-surround mechanism.
早期视觉系统是按照视网膜拓扑组织的。然而，在生态观看条件下，运动感知发生在非视网膜拓扑坐标中。尽管许多研究揭示了非视网膜拓扑过程的核心作用，但对于它们的机制和神经相关性知之甚少。塔丁和同事发现，增加高对比度漂移的 Gabor 的空间大小会降低运动方向的辨别能力，而对于低对比度的刺激则相反。研究结果表明，这反映了一种自适应的中心-周围拮抗作用，即在低对比度下，兴奋的中心占主导地位，而在高对比度下，抑制性的周围机制变得更加有效。由于生态视觉是非视网膜拓扑的，我们测试了一个假设，即非视网膜拓扑系统也通过自适应的中心-周围机制来处理运动信息。我们使用了特努斯-皮克勒显示器，旨在提供视网膜或非视网膜参考框架。我们的结果表明，运动感知的非视网膜拓扑过程也是由自适应的中心-周围机制介导的。
