Kountouriotis Georgios K, Shire Katy A, Mole Callum D, Gardner Peter H, Merat Natasha, Wilkie Richard M
Institute of Psychological Sciences, Institute for Transport Studies, University of Leeds, Leeds, UK.
J Vis. 2013 Aug 29;13(10):23. doi: 10.1167/13.10.23.
How do animals and insects use visual information to move through the world successfully? Optic flow, the pattern of motion at the eye, is a powerful source of information about self-motion. Insects and humans are sensitive to the global pattern of optic flow and try to maintain flow symmetry when flying or walking. The environments humans encounter, however, often contain demarcated paths that constrain future trajectories (e.g., roads), and steering has been successfully modeled using only road edge information. Here we examine whether flow asymmetries from a textured ground plane influences humans steering along demarcated paths. Using a virtual reality simulator we observed that different textures on either side of the path caused predictable biases to steering trajectories, consistent with participants reducing flow asymmetries. We also generated conditions where one textured region had no flow (either the texture was removed or the textured region was static). Despite the presence of visible path information, participants were biased toward the no-flow region consistent with reducing flow asymmetries. We conclude that optic flow asymmetries can lead to biased locomotor steering even when traveling along demarcated paths.
动物和昆虫如何利用视觉信息在世界中成功移动？光流，即眼睛处的运动模式，是关于自身运动的强大信息来源。昆虫和人类对光流的全局模式敏感，并在飞行或行走时试图保持流的对称性。然而，人类所遇到的环境通常包含划定的路径，这些路径会限制未来的轨迹（例如道路），并且仅使用道路边缘信息就已成功对转向进行了建模。在这里，我们研究来自有纹理的地面平面的流不对称性是否会影响人类沿着划定路径的转向。使用虚拟现实模拟器，我们观察到路径两侧不同的纹理会导致转向轨迹出现可预测的偏差，这与参与者减少流不对称性一致。我们还生成了一个有纹理的区域没有流的条件（要么纹理被移除，要么有纹理的区域是静止的）。尽管存在可见的路径信息，但参与者仍偏向于无流区域，这与减少流不对称性一致。我们得出结论，即使沿着划定的路径行进，光流不对称性也会导致运动转向出现偏差。
